• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    為人類健康服務(wù)的光學(xué)技術(shù)

    2022-01-06 05:25:00儲(chǔ)扎克ZacharySmith楊云舟
    國(guó)際人才交流 2021年11期
    關(guān)鍵詞:外泌體顯微鏡貧血

    文 / 儲(chǔ)扎克(Zachary J. Smith,美) 譯 / 楊云舟

    什么是科學(xué)研究?科學(xué)研究有其遵循的一定流程。首先,我們需要提出一個(gè)想法來(lái)構(gòu)成初步的假設(shè);其次,我們需要制定一個(gè)研究方案來(lái)驗(yàn)證假設(shè),精心設(shè)計(jì)并開(kāi)展試驗(yàn);最后,通過(guò)分析試驗(yàn)得出的數(shù)據(jù),我們能夠揭示最初的假設(shè)是否正確。如果假設(shè)錯(cuò)誤,我們就必須回到第一步,修改假設(shè),進(jìn)行“再研究”,再將流程循環(huán)到底。其實(shí),科學(xué)研究的方法可以越過(guò)純粹科學(xué)的邊界,應(yīng)用到生活中的許多方面。它實(shí)際上是幫助我們應(yīng)對(duì)和解決生活難題的一個(gè)視角。正因如此,我們發(fā)現(xiàn),有著嚴(yán)謹(jǐn)誠(chéng)實(shí)的態(tài)度并且秉持以公眾利益為重的科學(xué),掌握著世間所有問(wèn)題的答案,也擁有能夠改變世界的力量。

    那做科學(xué)家又是什么樣的呢?他是一個(gè)像謝爾頓·庫(kù)珀(美劇《生活大爆炸》中主角之一)那樣的人,還是一個(gè)整天做實(shí)驗(yàn)的實(shí)驗(yàn)室小白鼠?其實(shí),醫(yī)院里的醫(yī)生也是科學(xué)家,他們采集樣本,進(jìn)行測(cè)試,以驗(yàn)證他們的假設(shè)——醫(yī)療診斷——是否正確。某些政府領(lǐng)導(dǎo)人也是科學(xué)家,他們?cè)诓煌芯款I(lǐng)域都有著各自的科研成就,科學(xué)訓(xùn)練幫助他們更好地領(lǐng)導(dǎo)、治理我們的社會(huì)。

    我和我的研究團(tuán)隊(duì)將目光定格在了一個(gè)特殊的領(lǐng)域:生物醫(yī)學(xué)光子學(xué)。這一方向研究的基本思路是利用光子的力量來(lái)解決生物和醫(yī)藥領(lǐng)域的核心問(wèn)題。目前,我們的研究主要有3個(gè)分支:無(wú)標(biāo)記顯微技術(shù)、納米尺度拉曼光譜和成像,以及資源匱乏地區(qū)專用的醫(yī)療診斷技術(shù)。

    What is scientific research? It has its own internal cycle where the first step is to bring forward an idea, which will constitute your hypothesis. To examine this hypothesis you will need to come up with a research protocol and carry out well-designed experiments. Experiments produce data to be analyzed, thus revealing if the initial hypothesis is correct or not. And if not, we must return to the first step, revise our hypothesis, and “reresearch” until the whole cycle is completed. This method of scientific research can also be applied to many other aspects in life beyond the boundaries of strict science. The scientific method is actually a perspective through which to look at any problem we are faced with in life. It is with this idea we can see that science, carried out faithfully and in the public interest, possesses the answer to all our worldly problems and has the power to change the world.

    And what does it mean to be a scientist? Does it mean someone like “Sheldon Cooper”, or a lab rat spending all day carrying out experiments? It can also be a doctor in a hospital, who runs tests on collected samples to see if their hypothesis—their diagnosis- is correct or not. It can also be one of our government leaders, among whom there are many accomplished scientists specialized in different areas of studies. Scientific training has helped them become more proficient as leaders of our society.

    As for me and my team, our research fixes the eyes on one particular field: biomedical optics. The basic idea of this study is utilizing the power of light to solve problems crucial to our society that have risen in the realm of biology and medicine. Our research has three major branches, which are namely label-free microscopy, nanoscale Raman spectroscopy and imaging, and point of care technologies for resource-limited settings.

    無(wú)標(biāo)記顯微技術(shù)

    我們首先來(lái)看無(wú)標(biāo)記顯微技術(shù)。當(dāng)?shù)皖^看向自己的雙手時(shí),我們可以分辨出它們的顏色和背景是不一樣的。這種顏色的區(qū)別使我們能夠?qū)⑻囟ㄊ挛锱c附近的東西區(qū)分開(kāi)來(lái)。但一個(gè)自然狀態(tài)下的細(xì)胞是無(wú)色的,導(dǎo)致研究人員要想對(duì)它直接進(jìn)行觀測(cè)會(huì)十分困難。所以,如果我們想鎖定某個(gè)分子并對(duì)其進(jìn)行觀察,就要首先賦予它一種顏色——一種熒光標(biāo)記——使它變得易于區(qū)分。舉個(gè)例子,科學(xué)家可以給艾滋病毒打上熒光標(biāo)記。感染了艾滋病毒的細(xì)胞會(huì)和健康的細(xì)胞進(jìn)行信息交換,為病毒創(chuàng)造一條通道,讓它能夠移動(dòng)到正常細(xì)胞內(nèi)并感染正常細(xì)胞。如果成功地給病毒貼上了一個(gè)熒光標(biāo)記,研究人員就可以順利觀測(cè)到艾滋病毒在細(xì)胞間的移動(dòng)現(xiàn)象,并進(jìn)一步對(duì)其進(jìn)行研究。

    運(yùn)用新的技術(shù),我們能夠清晰地看到細(xì)胞的內(nèi)部結(jié)構(gòu)

    The Label-free Microscopy Technology

    The first is the label-free microscopy technology. Looking down at our hands, we can tell they have a different color than the background, which enables us to tell them apart from things nearby. But a cell in its natural form is colorless, difficult for researchers to observe. So, should we wish to find a certain molecule and look at it, we first have to give it a color—a fluorescent label—thus making it discernible. For example, we can give a fluorescent label to an HIV virus. A cell infected with HIV will exchange information with a healthy cell, creating a tunnel for the virus to move to and infect the normal cell. If labeled with fluorescence, the cell-to-cell movement of the HIV virus will become observable for researchers.

    As we can see from the example above, a fluorescent label is a powerful tool that allows us to see many things that have eluded our eyes before. Then why are scientists researching a “l(fā)abelfree” microscopy technology? First, the addition of a fluorescent label to a cell is challenging in itself—in fact, it might just kill the cell in the first place. Second, it is still not an easy task to observe the cell even with a fluorescent label. In order to capture better images, researchers will have to hit the labeled cell with a powerful laser beam, which will possibly overheat the cell or make it release toxic free radicals. Finally, even if researchers have succeeded in both labeling and keeping the cell alive, they still will face critical difficulty in observing it, since fluorescent labels can “break”, a process we call “photo-bleaching”, where the signal we receive gets weaker and weaker over time. Thus, the first image is very high quality, but the 10th or 20th image may be impossible to recognize. One of the solutions to this problem is to use a gentler laser, producing a poorer image of cells. Then we can take these poor-quality images and use a computer algorithm to help us enhance the quality, thus obtaining a relatively clearer image while protecting the cell. However, this method still has its limitations, and we nevertheless need to find other ways to observe the cell.

    從這個(gè)例子中我們可以看出,熒光標(biāo)記是一個(gè)非常有用的工具。通過(guò)這項(xiàng)技術(shù),我們能夠看到很多以前無(wú)法看到的東西。那么,為什么科學(xué)家們還要研究一種“無(wú)標(biāo)記”的顯微技術(shù)呢?原因在于,首先,給細(xì)胞打上熒光標(biāo)記本身就是一項(xiàng)挑戰(zhàn)。這一步驟很可能會(huì)直接殺死細(xì)胞。其次,即使有了熒光標(biāo)記,要觀察細(xì)胞仍然不是一件容易的事。為了捕捉到更好的圖像,研究人員必須用強(qiáng)大的激光束照射被標(biāo)記的細(xì)胞。這可能使得細(xì)胞過(guò)熱,或者釋放出有毒的自由基。最后,即使研究人員既成功地給細(xì)胞打上了標(biāo)記,又讓細(xì)胞存活了下來(lái),他們?cè)谟^察細(xì)胞時(shí)仍然會(huì)面臨關(guān)鍵性的困難。這是因?yàn)闊晒鈽?biāo)記可能會(huì)“破損”,這個(gè)過(guò)程被稱為“光漂白”,即隨著時(shí)間的推移,我們接收到的信號(hào)會(huì)越來(lái)越弱。因此,第1張圖像的質(zhì)量通常會(huì)非常好,但第10張或第20張圖像可能會(huì)變得無(wú)法識(shí)別。解決這個(gè)問(wèn)題的方法之一是使用較溫和的激光。較溫和的激光生成的細(xì)胞圖像質(zhì)量較差,但我們可以利用計(jì)算機(jī)算法來(lái)幫助我們提高這些照片的成像質(zhì)量,從而在保護(hù)細(xì)胞的同時(shí)獲得相對(duì)更清晰的圖像。但是,這種方法仍然有其局限性,科學(xué)家們還是需要尋找其他的方法來(lái)觀察細(xì)胞。

    To observe cells without fluorescent labels, scientists chose to utilize the outstanding work of Frits Zernike, the phase contrast microscope, (for which Zernike earned the Nobel Prize) and modify it to our demands. Beams of light that go through the cell move slower than those that move through the water surrounding the cell. This speed difference changes a property of light called its “phase”. Making use of this speed difference, the phase contrast microscope allows us to see colorless cells that are otherwise invisible. Yet the resolution of images coming from a phase contrast microscope is limited, and the information is “qualitative”, meaning that the brightness or dimness of certain parts of the cell cannot be exactly mapped to the cell’s real structure. Scientists need more to see better and as well deeper into a cell’s internal structure, and to make the measurement “quantitative”.

    為了能夠在沒(méi)有熒光標(biāo)記的情況下觀察細(xì)胞,科學(xué)家們選用了弗里茨·澤爾尼克發(fā)明的相襯顯微鏡(澤爾尼克也因此獲得了諾貝爾獎(jiǎng)),并根據(jù)需要對(duì)其進(jìn)行了一些改進(jìn)。一束光在穿過(guò)細(xì)胞時(shí)的速度會(huì)比穿過(guò)細(xì)胞周圍的液體時(shí)要慢,這種速度差異會(huì)影響到光的一種被稱為“相位”的屬性。利用速度差,相襯顯微鏡可以讓觀測(cè)者看到原本難以看見(jiàn)的無(wú)色細(xì)胞。然而,相襯顯微鏡只能呈現(xiàn)有限分辨率的圖像,而且,這些圖像都是“定性”信息。也就是說(shuō),圖像上細(xì)胞某些部位的明暗并不能準(zhǔn)確反映出細(xì)胞內(nèi)部的真實(shí)結(jié)構(gòu)??茖W(xué)家們需要更適合的技術(shù)來(lái)更全面、深入地觀察細(xì)胞的內(nèi)部結(jié)構(gòu),并使測(cè)量出的數(shù)據(jù)變得“定量”。

    The devising of the ultra-oblique illumination high resolution phase contrast microscope technology affords us with new insights into cells that are alive and functioning. We can now clearly visualize most of the cell’s internal structure, including lipid droplets, nucleus, mitochondria, vesicles, and a very tiny web-like structure called the endoplasmic reticulum. We can also notice many things that haven’t yet to be found up to this moment. For example, with this new technology, we have found out that many of the mitochondria within certain cells are always spinning, as if the mitochondria are dancing. This movement costs the cell energy, but cells are very conservative and don’t like to waste any energy. Therefore, this mitochondrial dancing must have an important reason behind it. Now we need to use the scientific method, and devise a hypothesis we can test through experiment to discover the answer to this question. Since the phase image does not “photobleach”, and the imaging does not hurt the cell, scientists now also have all the time in the world to look at the endoplasmic reticulum, an important organelle, and study the biological function behind its incessant shaking motion.

    超斜照明高分辨率相襯顯微鏡技術(shù)的出爐使得我們掌握了觀測(cè)活體正常細(xì)胞的全新角度。有了這項(xiàng)技術(shù),科學(xué)家可以清晰地看到細(xì)胞內(nèi)部的大部分結(jié)構(gòu),包括脂滴、細(xì)胞核、線粒體、液泡,以及一種非常微小的網(wǎng)狀結(jié)構(gòu)——內(nèi)質(zhì)網(wǎng)。我們還得以注意到從前沒(méi)有被發(fā)現(xiàn)過(guò)的東西。例如,我們發(fā)現(xiàn)在某些細(xì)胞內(nèi),許多線粒體總是在不停旋轉(zhuǎn),就像跳舞一樣。這種運(yùn)動(dòng)會(huì)消耗細(xì)胞的能量,但細(xì)胞通常都十分節(jié)約,不喜歡浪費(fèi)任何能量。因此,線粒體的這種“舞蹈”背后一定有著重要的原因。我們需要用科學(xué)的方法,提出一個(gè)假設(shè),通過(guò)實(shí)驗(yàn)來(lái)檢驗(yàn),由此發(fā)現(xiàn)這個(gè)問(wèn)題的答案。又如,內(nèi)質(zhì)網(wǎng)存在著一種不間斷的搖擺運(yùn)動(dòng)。由于新的顯微技術(shù)不存在“光漂白”效應(yīng),也不會(huì)傷害細(xì)胞,所以科學(xué)家們現(xiàn)在有充分的時(shí)間去觀察內(nèi)質(zhì)網(wǎng)不停搖擺背后的生物功能。

    拉曼光譜與成像

    既然已經(jīng)能夠?qū)?xì)胞內(nèi)部進(jìn)行更清晰的觀察,科學(xué)家們便開(kāi)始設(shè)想,是否可以進(jìn)一步觀察出這些內(nèi)部結(jié)構(gòu)之間在化學(xué)成分上的差異?要滿足這個(gè)雄心壯志,科學(xué)家們需要一種名為拉曼光譜的技術(shù)。簡(jiǎn)單來(lái)講,科學(xué)家會(huì)將一種顏色的光照射向細(xì)胞,而由于光線與不同化學(xué)成分之間的相互作用,許多不同顏色的光束會(huì)從細(xì)胞里折射出來(lái)。在光譜儀的幫助下,這些不同的顏色可以被分離成被我們稱為“光譜”的信號(hào),它可以告訴我們每種顏色各占多少。每個(gè)分子都有自己獨(dú)特的拉曼信號(hào)。而運(yùn)用拉曼光譜,我們可以分析出在細(xì)胞的每個(gè)部分存在著什么樣的化學(xué)分子。這項(xiàng)技術(shù)有著多種多樣的應(yīng)用。例如,通過(guò)觀察一個(gè)脂滴,科學(xué)家可以判斷出里面有什么,以及它是否由健康的脂肪構(gòu)成。通過(guò)進(jìn)一步分離并辨別細(xì)胞攝入的脂肪,我們甚至可以判斷出它是一個(gè)健康的細(xì)胞還是癌細(xì)胞。

    Raman Spectroscopy and Imaging

    With a clearer vision looking inside the cell, scientists also want to know, what are the chemical differences between these internal structures? The technique required for this ambition is called Raman spectroscopy. Basically, scientists shine one color of light onto a cell. Many different colors will come out from it due to the interaction of the light with different chemical components. With the help of a spectrometer, these colors can be separated into a signal we call a “spectrum”, which tells us how much of each color is present. The Raman spectrum can tell us what kind of chemicals are present within each point of the cell, because each molecule has its own unique Raman signal. Therefore, scientists, for example, can look at a lipid droplet and tell what’s inside and if it’s made of healthy fat or not. By separating the fat intake of a cell, we can even tell if it’s a healthy one or a cancer cell.

    這項(xiàng)技術(shù)還可以從其他角度對(duì)癌癥進(jìn)行診斷。目前,“細(xì)胞外小體”的研究是生物學(xué)中的一個(gè)新興領(lǐng)域,其中最受關(guān)注的是“外泌體”。外泌體是一種納米級(jí)大小的信使,它的功能類似細(xì)胞之間溝通時(shí)所發(fā)送的“信件”。外泌體包含蛋白質(zhì)和核酸,可以向附近的細(xì)胞發(fā)出指令。但是,不僅正常細(xì)胞會(huì)釋放外泌體,癌細(xì)胞也會(huì),而且數(shù)量往往比正常細(xì)胞多得多。事實(shí)上,癌細(xì)胞可以利用外泌體發(fā)送虛假信息,來(lái)欺騙本應(yīng)消滅它們的白細(xì)胞。在拉曼光譜儀下,我們能夠研究每一個(gè)外泌體的化學(xué)成分,并分析它們之間的微小差異。針對(duì)這一點(diǎn),科學(xué)家們使用一種叫作“光鑷”的工具,挑選出單個(gè)的外泌體進(jìn)行深入研究。我們用這種方法發(fā)現(xiàn),癌細(xì)胞和健康細(xì)胞的外泌體有著不同結(jié)構(gòu)的表面蛋白。這無(wú)疑將為癌癥的研究、診斷及可能的新治療手段提供參考。

    This technology can take on cancer diagnosis from other perspectives. A new topic in biology is the study of “extracellular vesicles”, among which one of the most studied is called an “exosome”. The exosome is a nanoscale messenger. It functions like a letter sent between cells for communication purposes. It contains proteins and nucleic acids that can give instructions to nearby cells. Not only do normal cells release these exosomes, but cancer cells also release them, often in much higher numbers than normal cells. In fact, cancer cells can use exosomes to send false information to trick the white blood cells that are supposed to eliminate them. Using Raman spectroscopy, we can study the chemical composition of each individual exosome and see that every exosome is a little bit different from one another. Regarding this, scientists use a tool called optical tweezers to pick up each single exosome and examine them closely. We found that the surface protein of the exosome is different between a cancer cell and a healthy one, which can provide new information for cancer studies, cancer diagnosis, and possibly cancer treatments.

    適于資源匱乏地區(qū)的醫(yī)療診斷技術(shù)

    除了解決分子層面的生物學(xué)問(wèn)題,光學(xué)科學(xué)還可以為組織層面的醫(yī)學(xué)問(wèn)題作出貢獻(xiàn)。人們生病了會(huì)去“看醫(yī)生”,但其實(shí)是“醫(yī)生在看你”——醫(yī)生通過(guò)顯微鏡觀察你的組織或血液樣本。值得一提的是,近一個(gè)世紀(jì)以來(lái),醫(yī)生使用的顯微技術(shù)幾乎沒(méi)有根本性的變革。也許,科學(xué)家們?cè)谙嚓P(guān)領(lǐng)域通力合作,如讓顯微鏡變得更小、更智能,也能推動(dòng)醫(yī)用顯微技術(shù)的進(jìn)步。

    Care Technologies for Resource-limited Settings

    Besides biological questions at the molecular level, optical science can also contribute to medical questions at a tissue level. When we are sick, it is natural for us to “see a doctor”. What really happens is “the doctor sees you”—the doctor looks at the tissue or blood sample of yours through a microscope. The microscopic technology used by doctors, in fact, hasn’t really changed in almost a century. Maybe through the coordinated efforts of scientists, we can improve medical microscopes, for instance, by making them smaller and smarter.

    人們希望無(wú)論何時(shí)何地都能獲得高質(zhì)量的醫(yī)療服務(wù)。但在現(xiàn)實(shí)生活中,患者必須去到特定的地方——醫(yī)院——才能順利就診。醫(yī)院配備有所有可能需要的專業(yè)設(shè)備和儀器,它們將幫助醫(yī)生進(jìn)行測(cè)試,做出可靠、準(zhǔn)確的診斷。但這些設(shè)備往往體積龐大、價(jià)格昂貴,而且需要經(jīng)過(guò)大量的培訓(xùn)才能操作。如果你居住在一個(gè)發(fā)達(dá)國(guó)家的城市,這樣的資源對(duì)你來(lái)說(shuō)可能唾手可得。但那些生活在貧困(如非洲農(nóng)村)或偏遠(yuǎn)地區(qū)(如西藏地區(qū))的人所面臨的情況就大不相同了,在那里資源稀缺且十分昂貴,患者往往需要幾天甚至幾周的時(shí)間才能就醫(yī)。為了讓醫(yī)療服務(wù)更方便、便捷,科學(xué)家們考慮將我們的日常工具改造成醫(yī)療設(shè)備。手機(jī)是否能夠承擔(dān)這樣的工作?它有攝像頭、麥克風(fēng),內(nèi)置電腦和網(wǎng)絡(luò)模塊。如果再加上一個(gè)鏡頭,它基本上就能變成一臺(tái)顯微鏡,足以用來(lái)進(jìn)行疾病觀察、細(xì)胞計(jì)數(shù),甚至成為一臺(tái)光譜儀。當(dāng)我們制造出這樣一個(gè)簡(jiǎn)單的手機(jī)顯微鏡時(shí),我們發(fā)現(xiàn)它的確可以達(dá)到很好的顯微效果,觀察到細(xì)胞核和瘧疾寄生蟲(chóng)。然而,我們隨后發(fā)現(xiàn),盡管手機(jī)顯微鏡具有成為便捷醫(yī)療工具的潛力,但它只適合那些具備專業(yè)操作技術(shù)的人。在手機(jī)顯微鏡的成像方面,由訓(xùn)練有素的實(shí)驗(yàn)室研究人員操作出的圖像和由醫(yī)院工作人員或其他沒(méi)有接受過(guò)使用培訓(xùn)的人操作出的圖像可能在質(zhì)量上差異很大。為了更適應(yīng)醫(yī)療衛(wèi)生從業(yè)的需要,我們的低成本顯微鏡必須更智能,必須對(duì)那些不十分熟悉光學(xué)科學(xué)的人更加友好。于是,我們研發(fā)出了一種新型“全自動(dòng)” 微鏡。它可以自動(dòng)聚焦和掃描微小的微觀樣品,體積小,便于攜帶,操作也不需要經(jīng)過(guò)額外培訓(xùn),還能觀察從血液、糞便到組織樣品的多種類型的樣品。相比之下,雖然普通的自動(dòng)顯微鏡可以生成質(zhì)量稍好的圖像,但價(jià)格要比我們的顯微鏡貴很多倍。此外,新型顯微鏡非常便于組裝,材料在網(wǎng)上很容易就能買到,基本上就像一套樂(lè)高玩具一樣。

    It is a universal dream to have access to high quality medical care whenever and wherever we want, which is in stark contrast to the reality where patients must go to certain places—hospitals—for that is where all the professional equipment and machines are. These machines help doctors run tests and make solid diagnoses. But they tend to be large, expensive, and require extensive training to operate. If you are an urban citizen in a developed country, such resources might be not so difficult to get. Things are very different for those live in poorer areas where such resources are scarce and exorbitantly priced, like rural Africa, or a remote district—like Tibet—where it takes days, even weeks, to reach a hospital.

    To make medical services more convenient and accessible, scientists are thinking to turn everyday gadgets into medical devices. Can cellphone take up such a job? It has a camera, a microphone, a built-in computer and network modules. With a lens added on, a cellphone can be essentially modified into a microscope that can be used to look at diseases, count cells, and even become a spectrograph. When we developed a simple cellphone microscope, we found we could achieve excellent results, being able to see cell nuclei and malaria parasites. Yet for all the potential it has to become a convenient medical tool, we found out that it only suits those with specialized know-how, as images produced using a cellphone microscope can vary a great deal between those operated by trained lab researchers and those operated by hospital staff or others who have not been trained in the cellphone microscope’s use. In order to truly impact health care, our low-cost microscope must be made smarter and more friendly to those who are not so familiar with optical science. A new type of microscope was then made to satisfy this demand. It is a “fully-automated” microscope that can automatically focus and scan tiny microscopic samples, has a portable size, requires no additional training, and can look at many types of samples, from blood to feces to tissue samples. In comparison, a normal automated microscope can produce slightly better images, but is many times more expensive than our microscope. Ours is easy to put together, basically like a Lego set, and can be set up with materials that can be easily purchased online.

    低成本、全自動(dòng)的顯微平臺(tái)

    我們的自動(dòng)顯微鏡可以應(yīng)用于許多不同的醫(yī)療場(chǎng)景。它可以協(xié)助進(jìn)行動(dòng)物診療。眾所周知,山羊是雜食動(dòng)物,因此很容易遭到寄生蟲(chóng)的感染。在對(duì)山羊進(jìn)行寄生蟲(chóng)檢查時(shí),獸醫(yī)通常會(huì)先從山羊的糞便中取樣,與水混合,然后再放在顯微鏡下分辨并歸類樣品中的寄生蟲(chóng)卵。如果采取純手工操作的方法,這套流程會(huì)非常累人。醫(yī)生一般需要花20—30分鐘的時(shí)間來(lái)仔細(xì)研究樣本。而我們的自動(dòng)顯微鏡可以自主對(duì)動(dòng)物的大便樣本進(jìn)行細(xì)節(jié)拍照,隨后利用深度學(xué)習(xí)技術(shù),自動(dòng)從圖像中挑出蟲(chóng)卵,進(jìn)行計(jì)數(shù),并分辨出這些蟲(chóng)卵是來(lái)自蛔蟲(chóng)、壯蟲(chóng)還是其他寄生蟲(chóng)。這樣一來(lái),既節(jié)省了醫(yī)生的時(shí)間,又可以幫助動(dòng)物盡快得到正確的藥物治療,減少它們的痛苦。新型顯微鏡在人類體檢中也有用處。當(dāng)我們?nèi)タ床r(shí),醫(yī)生通常會(huì)先抽取一小瓶血。通過(guò)統(tǒng)計(jì)血液中紅細(xì)胞、白細(xì)胞和血小板的數(shù)量,醫(yī)生能夠掌握我們的健康狀況。對(duì)于老年人,尤其是對(duì)罹患癌癥的老年人來(lái)說(shuō),定期查血是很重要的一項(xiàng)檢查。治療癌癥的藥物不僅會(huì)殺死癌細(xì)胞,還會(huì)傷害到身體其他健康的部位,所以醫(yī)生要時(shí)刻監(jiān)測(cè)患者血液中的白細(xì)胞水平,避免其降低到臨界水平以下。目前,患者只能去醫(yī)院查血,而每個(gè)月可能只查一兩次。這就造成了醫(yī)生在信息掌握上的滯后。一種理想的情況是患者每天在家里就能自己驗(yàn)血。我們的新型、便捷、適合家庭使用的顯微鏡或許能夠?yàn)樗麄兲峁椭;颊呖梢詫⒀簶颖九c一種特殊液體混合,然后放在我們的顯微鏡下。顯微鏡會(huì)自動(dòng)掃描樣品,進(jìn)行分析,然后計(jì)數(shù)。不同種類的細(xì)胞——如紅細(xì)胞或白細(xì)胞——在輸出圖像中會(huì)顯示為不同的顏色或亮度。整個(gè)系統(tǒng)完全自動(dòng),所以即使是由業(yè)余的爸爸媽媽們來(lái)操作,得出的檢測(cè)結(jié)果也可以和專業(yè)的研究人員一樣準(zhǔn)確、可靠。

    Our automated microscope can find application in many different medical scenarios. As one example, we have shown how it can help treat animals. Goats are known to be messy eaters, and are consequently very easily infected by parasites like parasitic worms. The usual procedure for a vet to perform a parasite check on a goat is first taking a sample from its feces, mixing it with water, then putting it under a microscope to tell apart and classify the parasite eggs in the sample. This can be exhausting if done manually. It usually takes 20—30 minutes of the doctor’s careful study. Our automated microscope can take a detailed pictures of a large sample of the animal’s feces and, subsequently, using deep learning technology, pick out eggs from the image automatically, count them, and tell us if they are from ascarids, strongyles or other parasites. This can save the doctor’s time, and help the animal to get the correct drug as soon as possible, reducing its suffering.

    This can also be applied to the medical examination for human beings. When seeing a doctor, it is a common practice to have a vial of blood taken. By counting the number of red blood cells, white blood cells and platelets, our blood serves as a window of our health status in the eyes of a doctor. Regular blood checkups are important for the elderly, especially those who have cancer. Drugs used in cancer treatment will not only kill the cancer cells but also hurt the healthy body parts, so doctors will want to monitor the white blood cell level in the patient’s blood to avoid it reducing beyond a critical level. Using current technology, patients have their blood tested only when going to a hospital, which probably only happens once or twice a month. This creates a time-lag of information on the doctor’s side. The ideal for us is to enable the patient to have his or her blood tested right at their own homes on a daily basis. Our new, convenient, household friendly microscope is qualified to help. Blood samples from patients will be mixed with a special liquid that prepares the sample and put under our microscope. Samples will be automatically scanned, analyzed and counted. Different kinds of cells, like red cells or different types of white blood cells in the output image will have different colors or brightness. Because the system is totally automatic, in our experiments the test results obtained by amateur moms and dads can be just as accurate and reliable as those of professional researchers.

    即使是要給動(dòng)物抽血,我們的顯微鏡也能幫上忙。動(dòng)物并不了解健康檢查的重要性,所以,為了抽血這一過(guò)程不刺激到它們或讓它們不安,醫(yī)務(wù)人員會(huì)盡可能輕柔地從它們身上抽取盡可能少量的血。我們的系統(tǒng)只需要幾微升(不到一滴)的血液就足以得到準(zhǔn)確的檢測(cè)結(jié)果,因此能夠非常好地適應(yīng)這項(xiàng)工作的特殊條件。

    And even when it comes to draw blood from animals, our microscope can get the job done. Animals don’t understand the importance of health check-ups. To not irritate or upset them, medical practitioners would wish to take as little blood as possible from them, and in the most gentle manner. Our system requires only a few microliters (less than one drop) of blood, and it’s sufficient to get an accurate test result.

    最后,我們的技術(shù)還可以在另一個(gè)重要領(lǐng)域——貧血診斷——中發(fā)揮作用。貧血是全球公共衛(wèi)生面臨的一大嚴(yán)重威脅,影響著全球約1/3的人口,尤其是那些醫(yī)療資源稀缺地區(qū)的人。中國(guó)有10%—20%的兒童患有缺鐵性貧血,通常與營(yíng)養(yǎng)不良有關(guān);有4300萬(wàn)兒童患有地中海貧血,這是一種遺傳性貧血,常見(jiàn)于泰國(guó)、越南及中國(guó)的廣東和廣西。這兩種不同的疾病對(duì)治療方法有著不同的要求。對(duì)于缺鐵性貧血,治療方法可以非常簡(jiǎn)單——提高鐵質(zhì)攝入量;然而,對(duì)于地中海貧血的患者來(lái)說(shuō)則相反,鐵的攝入對(duì)他們非常危險(xiǎn)。正因如此,我們希望能夠?qū)ι鐣?huì)中的每個(gè)公民進(jìn)行貧血檢測(cè)。但讓全國(guó)人民都去醫(yī)院看病檢測(cè)是一件不可能的事,所以我們需要研發(fā)一種儀器,可以在醫(yī)院外使用,價(jià)格便宜,每個(gè)城市都可以有幾個(gè)這樣的儀器。在貧血篩查過(guò)程中,第一項(xiàng)任務(wù)是找到那些貧血的人;第二項(xiàng)任務(wù)是診斷出患者所患的是哪種貧血。人體內(nèi)紅細(xì)胞的形狀和大小不盡相同,而健康人、缺鐵性貧血患者和地中海貧血患者之間的紅細(xì)胞也不一樣。但是,由于缺鐵性貧血患者和地中海貧血患者的紅細(xì)胞大小及形狀的差異非常微小,所以,通常需要大型昂貴的設(shè)備才能成功區(qū)分。這些設(shè)備在醫(yī)院以外的地方很難操作,所以我們采用了一種低成本的光學(xué)散射系統(tǒng)來(lái)測(cè)量紅細(xì)胞的大小、形狀或血紅蛋白濃度等參數(shù)。通過(guò)我們這套系統(tǒng)產(chǎn)生的數(shù)據(jù),醫(yī)生幾乎可以100%準(zhǔn)確地區(qū)分貧血患者和健康人。在缺鐵性貧血患者和地中海貧血患者的區(qū)分上,這套系統(tǒng)能達(dá)到超過(guò)90%的準(zhǔn)確率。我們希望在未來(lái),這樣的技術(shù)可以順利應(yīng)用于大范圍、全人口的貧血篩查。

    Last but not least, there is one more application where our technology can pitch in—the diagnosis of anemia. Anemia is a serious threat to public health globally as it’s affecting around one third of the world’s population, especially plaguing those who have the least access to competent medical resources. 10%~20% percent of children in China have iron deficiency anemia, which is related to malnutrition; 43 million in China have thalassemia, a genetic type of anemia, which is commonly found in Thailand, Vietnam, Guangdong and Guangxi in China. These two different diseases should be countered with different treatments. For iron deficiency anemia, the solution can be as simple as boosting up one’s iron intake. Yet on the contrary, iron intake is dangerous for patients with thalassemia. Because of this, we would like to test every citizen for anemia, but it’s not possible to have the whole country go to the doctor to get tested. We need to make an instrument which can be taken outside of the hospital, and is inexpensive enough that every town can have several such instruments. In this screening process the first job is to find those with anemia and the second job is to tell which kind of anemia it is. Blood cells are not the same in shapes and sizes, and they are different among a healthy person, an iron deficiency anemia patient and a thalassemia patient. However, because the size and shape differences are very tiny in iron deficiency and thalassemia, to differentiate blood cells according to their sizes normally requires large and expensive devices that are not easy to operate outside of a hospital. So we have come up with a low cost optical scattering system that can be used to measure parameters of red blood cells like size, shape, or hemoglobin concentration. With data produced from our system, doctors can tell an anemic patient from healthy people with nearly 100% accuracy, and separate iron deficiency anemia patients and thalassemia patients with an accuracy over 90%. We hope in the future such a technology could be used for widespread, whole population screening of anemia.

    光的力量可以幫助我們解決許多生物和醫(yī)學(xué)上的問(wèn)題,助力我們改善現(xiàn)在所處的社會(huì)。光學(xué)科學(xué)的發(fā)展是許多杰出科學(xué)家努力的結(jié)果。每一位科學(xué)家都是“站在巨人的肩膀上”貢獻(xiàn)自己的微薄之力。在他們的共同貢獻(xiàn)下,世界可以變得更加美好。

    The power of light can help solve many biological and medical questions, tackle challenges, and change the society we are now living in. The development of optical science is the results of effort from many outstanding scientists. Each scientist “stands on the shoulders of giants”, and tries to add their own small contribution to the greater good. Thanks to their combined contributions, the world can be a better place for all of us.

    猜你喜歡
    外泌體顯微鏡貧血
    外泌體miRNA在肝細(xì)胞癌中的研究進(jìn)展
    蹲久了站起來(lái)眼前發(fā)黑就是貧血?
    間充質(zhì)干細(xì)胞外泌體在口腔組織再生中的研究進(jìn)展
    中醫(yī)怎么防治貧血
    春困需防貧血因
    循環(huán)外泌體在心血管疾病中作用的研究進(jìn)展
    你會(huì)使用顯微鏡嗎
    你對(duì)貧血知多少
    顯微鏡
    外泌體在腫瘤中的研究進(jìn)展
    亚洲熟女毛片儿| 男女下面插进去视频免费观看| 久久亚洲真实| 欧美人与性动交α欧美精品济南到| 亚洲欧美激情综合另类| 久久热在线av| 亚洲欧美精品综合一区二区三区| 婷婷精品国产亚洲av在线| 两个人免费观看高清视频| 美女高潮到喷水免费观看| 亚洲一码二码三码区别大吗| 亚洲一区高清亚洲精品| 中文字幕高清在线视频| 天天躁夜夜躁狠狠躁躁| 啦啦啦 在线观看视频| 色精品久久人妻99蜜桃| 亚洲国产中文字幕在线视频| 欧美日韩瑟瑟在线播放| 亚洲第一av免费看| 日本免费a在线| 在线观看免费午夜福利视频| 丰满迷人的少妇在线观看| 久久精品亚洲熟妇少妇任你| 亚洲欧美日韩无卡精品| 国产av精品麻豆| 国产欧美日韩一区二区精品| 两个人看的免费小视频| 妹子高潮喷水视频| 亚洲av美国av| a级毛片在线看网站| 成人国语在线视频| 咕卡用的链子| 亚洲国产毛片av蜜桃av| 丝袜美腿诱惑在线| 日韩一卡2卡3卡4卡2021年| 午夜免费鲁丝| 欧美亚洲日本最大视频资源| 亚洲第一青青草原| 黄片大片在线免费观看| 久久影院123| 手机成人av网站| 午夜影院日韩av| 亚洲熟妇熟女久久| 欧美日韩福利视频一区二区| 亚洲精品久久午夜乱码| 天天添夜夜摸| 桃色一区二区三区在线观看| 亚洲午夜理论影院| 亚洲精品一区av在线观看| 国产成年人精品一区二区 | 国产成人免费无遮挡视频| 在线观看66精品国产| 欧美av亚洲av综合av国产av| 午夜亚洲福利在线播放| 首页视频小说图片口味搜索| 国产伦一二天堂av在线观看| 国产亚洲精品第一综合不卡| 久久中文字幕一级| 亚洲成国产人片在线观看| 日日摸夜夜添夜夜添小说| 亚洲熟女毛片儿| 日韩欧美一区视频在线观看| 超色免费av| 色尼玛亚洲综合影院| www日本在线高清视频| 久久久久亚洲av毛片大全| 亚洲久久久国产精品| 亚洲一区二区三区欧美精品| 成人18禁高潮啪啪吃奶动态图| 欧美不卡视频在线免费观看 | svipshipincom国产片| 久久久久国产精品人妻aⅴ院| 村上凉子中文字幕在线| 亚洲av熟女| 狂野欧美激情性xxxx| 国产熟女xx| 国产亚洲精品第一综合不卡| 精品免费久久久久久久清纯| 在线播放国产精品三级| 黄色 视频免费看| 国产蜜桃级精品一区二区三区| 欧美在线一区亚洲| 亚洲情色 制服丝袜| 在线观看www视频免费| 日韩成人在线观看一区二区三区| 亚洲精品中文字幕一二三四区| 成人国语在线视频| 黄色成人免费大全| 久久精品aⅴ一区二区三区四区| 一夜夜www| 久久精品国产99精品国产亚洲性色 | 国产亚洲精品久久久久5区| 桃色一区二区三区在线观看| 手机成人av网站| 欧美黑人精品巨大| 亚洲色图 男人天堂 中文字幕| 午夜免费鲁丝| 麻豆久久精品国产亚洲av | 亚洲成a人片在线一区二区| 中文字幕最新亚洲高清| 精品国产亚洲在线| 在线天堂中文资源库| 久9热在线精品视频| 我的亚洲天堂| 久久久久亚洲av毛片大全| 午夜福利免费观看在线| 欧美成人免费av一区二区三区| 99国产精品一区二区三区| 在线观看一区二区三区激情| 中国美女看黄片| 丰满迷人的少妇在线观看| 免费在线观看影片大全网站| 琪琪午夜伦伦电影理论片6080| 精品一区二区三区四区五区乱码| 757午夜福利合集在线观看| 国产不卡一卡二| 日韩av在线大香蕉| 黄片播放在线免费| 国产精品影院久久| 在线观看午夜福利视频| 日日摸夜夜添夜夜添小说| 99久久人妻综合| 中文字幕另类日韩欧美亚洲嫩草| 亚洲精品国产色婷婷电影| 午夜福利影视在线免费观看| 在线观看一区二区三区| 欧美成狂野欧美在线观看| 久久青草综合色| 嫩草影视91久久| 日韩欧美免费精品| 国产精品 欧美亚洲| 超碰97精品在线观看| 老汉色av国产亚洲站长工具| 国产国语露脸激情在线看| 精品久久久精品久久久| 国产蜜桃级精品一区二区三区| 制服诱惑二区| 好看av亚洲va欧美ⅴa在| 天天躁狠狠躁夜夜躁狠狠躁| 99riav亚洲国产免费| 亚洲国产中文字幕在线视频| 亚洲欧美激情在线| 欧美激情极品国产一区二区三区| 精品久久蜜臀av无| 黄色成人免费大全| 日本黄色日本黄色录像| 精品久久久久久电影网| 国产精品1区2区在线观看.| 久久精品国产清高在天天线| 99久久精品国产亚洲精品| 老司机亚洲免费影院| 国产主播在线观看一区二区| 真人一进一出gif抽搐免费| 精品高清国产在线一区| 在线观看一区二区三区| 99在线视频只有这里精品首页| 亚洲欧美日韩高清在线视频| 欧美日本亚洲视频在线播放| 超色免费av| 99精品在免费线老司机午夜| 丁香欧美五月| 91国产中文字幕| 久久青草综合色| 国产精品影院久久| 日韩高清综合在线| 咕卡用的链子| av欧美777| 又大又爽又粗| 黄色毛片三级朝国网站| 精品一品国产午夜福利视频| 别揉我奶头~嗯~啊~动态视频| 亚洲精品av麻豆狂野| 亚洲精品一区av在线观看| 夜夜爽天天搞| 国产在线精品亚洲第一网站| 在线观看一区二区三区激情| 国产黄色免费在线视频| 国产免费男女视频| 国产蜜桃级精品一区二区三区| 成人黄色视频免费在线看| 丝袜美足系列| 亚洲激情在线av| 亚洲一卡2卡3卡4卡5卡精品中文| 亚洲午夜精品一区,二区,三区| 午夜福利,免费看| 很黄的视频免费| 久久久久国产精品人妻aⅴ院| 黄片小视频在线播放| 99久久国产精品久久久| av免费在线观看网站| 免费高清视频大片| 自拍欧美九色日韩亚洲蝌蚪91| 黑人巨大精品欧美一区二区mp4| 亚洲精品国产精品久久久不卡| 国产单亲对白刺激| 老司机靠b影院| 国产av精品麻豆| 成人18禁在线播放| 久久久久亚洲av毛片大全| av超薄肉色丝袜交足视频| 精品国产乱子伦一区二区三区| 村上凉子中文字幕在线| 波多野结衣一区麻豆| 亚洲欧美一区二区三区久久| 久久精品国产清高在天天线| 国产成人欧美在线观看| 久久婷婷成人综合色麻豆| av在线天堂中文字幕 | 国产又色又爽无遮挡免费看| 欧美精品一区二区免费开放| 曰老女人黄片| 亚洲狠狠婷婷综合久久图片| 国产日韩一区二区三区精品不卡| 伊人久久大香线蕉亚洲五| 51午夜福利影视在线观看| 久久热在线av| 国产精品香港三级国产av潘金莲| 国产欧美日韩综合在线一区二区| 黑人巨大精品欧美一区二区mp4| 亚洲狠狠婷婷综合久久图片| 午夜免费鲁丝| 少妇被粗大的猛进出69影院| 国产极品粉嫩免费观看在线| 9热在线视频观看99| 欧美激情极品国产一区二区三区| 久久久久精品国产欧美久久久| 午夜精品国产一区二区电影| 日韩大码丰满熟妇| 国产精品久久久久成人av| 久久中文看片网| 精品一区二区三区四区五区乱码| 欧美亚洲日本最大视频资源| 久久精品91无色码中文字幕| 在线观看免费高清a一片| 久久精品aⅴ一区二区三区四区| 无人区码免费观看不卡| 亚洲成人免费电影在线观看| 国产成人精品无人区| 黄色a级毛片大全视频| 美女午夜性视频免费| 如日韩欧美国产精品一区二区三区| 欧美乱码精品一区二区三区| 成年人免费黄色播放视频| 国产亚洲欧美精品永久| 亚洲少妇的诱惑av| 欧美日韩一级在线毛片| 亚洲精品成人av观看孕妇| av在线天堂中文字幕 | 久久亚洲精品不卡| 亚洲成a人片在线一区二区| 夜夜看夜夜爽夜夜摸 | 在线国产一区二区在线| 美女高潮喷水抽搐中文字幕| 国产精品亚洲av一区麻豆| 999久久久精品免费观看国产| 国产亚洲精品久久久久5区| 男女下面插进去视频免费观看| av国产精品久久久久影院| 久久久久亚洲av毛片大全| 超色免费av| 欧美 亚洲 国产 日韩一| 久久精品影院6| av网站在线播放免费| 午夜视频精品福利| 国产色视频综合| 亚洲色图av天堂| 国产亚洲欧美在线一区二区| 制服人妻中文乱码| 国产主播在线观看一区二区| 成熟少妇高潮喷水视频| 日本五十路高清| 成年人黄色毛片网站| 欧美日韩精品网址| 少妇裸体淫交视频免费看高清 | 男人舔女人下体高潮全视频| 日韩一卡2卡3卡4卡2021年| 亚洲精品中文字幕在线视频| 精品福利永久在线观看| 两性午夜刺激爽爽歪歪视频在线观看 | 欧美中文日本在线观看视频| 18禁观看日本| 一区在线观看完整版| 九色亚洲精品在线播放| 黄频高清免费视频| 99国产精品99久久久久| 免费av毛片视频| www国产在线视频色| 免费在线观看影片大全网站| 国产精品偷伦视频观看了| 热99国产精品久久久久久7| 19禁男女啪啪无遮挡网站| 久久伊人香网站| 午夜免费成人在线视频| 欧美日韩福利视频一区二区| 一区二区三区激情视频| 高清黄色对白视频在线免费看| 亚洲午夜理论影院| 免费高清视频大片| 怎么达到女性高潮| 欧美激情 高清一区二区三区| 精品日产1卡2卡| 久久人人精品亚洲av| tocl精华| 中文亚洲av片在线观看爽| 亚洲七黄色美女视频| 日日摸夜夜添夜夜添小说| 亚洲成人国产一区在线观看| 午夜久久久在线观看| 国产野战对白在线观看| 麻豆国产av国片精品| 午夜激情av网站| av在线天堂中文字幕 | 99热只有精品国产| 夫妻午夜视频| 国产又爽黄色视频| 夜夜夜夜夜久久久久| 伊人久久大香线蕉亚洲五| 欧美乱妇无乱码| 久久香蕉精品热| cao死你这个sao货| a级毛片黄视频| 日韩欧美免费精品| 日韩国内少妇激情av| 美女高潮到喷水免费观看| 夜夜躁狠狠躁天天躁| a级片在线免费高清观看视频| 中文字幕色久视频| 美女午夜性视频免费| 久久精品国产99精品国产亚洲性色 | 黄色成人免费大全| 国产精品 国内视频| 日本黄色视频三级网站网址| 丝袜人妻中文字幕| 精品少妇一区二区三区视频日本电影| av超薄肉色丝袜交足视频| 免费日韩欧美在线观看| 亚洲欧美一区二区三区黑人| 日韩免费高清中文字幕av| 美女高潮到喷水免费观看| 脱女人内裤的视频| 亚洲熟妇中文字幕五十中出 | 国产亚洲欧美在线一区二区| 久久国产亚洲av麻豆专区| 欧美黄色片欧美黄色片| 久久伊人香网站| 美女午夜性视频免费| www国产在线视频色| 国产男靠女视频免费网站| 视频区图区小说| 国产成人欧美| 99在线视频只有这里精品首页| 日韩中文字幕欧美一区二区| 国产成人影院久久av| 国产精品99久久99久久久不卡| 亚洲一码二码三码区别大吗| 曰老女人黄片| a级毛片在线看网站| 午夜激情av网站| 国产成人精品久久二区二区91| 亚洲自偷自拍图片 自拍| 精品久久久久久久毛片微露脸| 中文字幕av电影在线播放| 免费高清视频大片| 日日爽夜夜爽网站| 琪琪午夜伦伦电影理论片6080| 免费观看精品视频网站| 老汉色av国产亚洲站长工具| 国产精品电影一区二区三区| 90打野战视频偷拍视频| 99久久99久久久精品蜜桃| 久久久国产精品麻豆| 国产成人精品久久二区二区免费| 视频区欧美日本亚洲| 脱女人内裤的视频| av有码第一页| 9191精品国产免费久久| 一个人免费在线观看的高清视频| 欧美乱色亚洲激情| 日韩三级视频一区二区三区| 正在播放国产对白刺激| 免费av毛片视频| 正在播放国产对白刺激| 一夜夜www| ponron亚洲| 午夜精品久久久久久毛片777| 9热在线视频观看99| 国产成年人精品一区二区 | 在线天堂中文资源库| 脱女人内裤的视频| av有码第一页| 午夜91福利影院| 91av网站免费观看| 9热在线视频观看99| 中亚洲国语对白在线视频| 九色亚洲精品在线播放| 91国产中文字幕| 身体一侧抽搐| 日本wwww免费看| 久久欧美精品欧美久久欧美| 中文字幕色久视频| 黄色女人牲交| 国产人伦9x9x在线观看| 亚洲男人天堂网一区| 久久久久久久久免费视频了| 亚洲熟妇熟女久久| 欧美日韩国产mv在线观看视频| 亚洲性夜色夜夜综合| 女人爽到高潮嗷嗷叫在线视频| 久久中文字幕一级| 9热在线视频观看99| 最近最新免费中文字幕在线| 亚洲精品成人av观看孕妇| 桃红色精品国产亚洲av| 12—13女人毛片做爰片一| 99在线视频只有这里精品首页| 午夜精品国产一区二区电影| 美女 人体艺术 gogo| 亚洲精品在线观看二区| 色综合欧美亚洲国产小说| 一级a爱片免费观看的视频| 一级片'在线观看视频| 国产精品久久久人人做人人爽| 美女扒开内裤让男人捅视频| 亚洲精品一二三| xxxhd国产人妻xxx| 国产精品爽爽va在线观看网站 | 欧美日韩福利视频一区二区| 韩国精品一区二区三区| 国产成人欧美在线观看| 国产高清激情床上av| 最新美女视频免费是黄的| 亚洲成av片中文字幕在线观看| 久久青草综合色| 国产精品爽爽va在线观看网站 | 欧美中文日本在线观看视频| av欧美777| 国产片内射在线| 欧美黄色片欧美黄色片| 色综合婷婷激情| 国产有黄有色有爽视频| 精品福利观看| 欧美色视频一区免费| 午夜视频精品福利| 亚洲成国产人片在线观看| 一a级毛片在线观看| 亚洲精品国产色婷婷电影| 国产精品一区二区三区四区久久 | 美女 人体艺术 gogo| 男女午夜视频在线观看| 熟女少妇亚洲综合色aaa.| 婷婷六月久久综合丁香| 久久热在线av| 久久久精品欧美日韩精品| 香蕉久久夜色| 电影成人av| 日韩中文字幕欧美一区二区| bbb黄色大片| av中文乱码字幕在线| 成人三级做爰电影| 一进一出好大好爽视频| 国产三级黄色录像| 黄片播放在线免费| 亚洲中文av在线| 国产亚洲精品一区二区www| 亚洲国产精品一区二区三区在线| 在线观看免费视频日本深夜| 午夜精品久久久久久毛片777| 99久久人妻综合| 亚洲中文av在线| 国产免费男女视频| 中国美女看黄片| 久久久久久人人人人人| 老司机午夜福利在线观看视频| 久久精品aⅴ一区二区三区四区| 精品久久久久久久久久免费视频 | 久久人人爽av亚洲精品天堂| 国产成人精品在线电影| 欧美日韩精品网址| 亚洲色图 男人天堂 中文字幕| 婷婷精品国产亚洲av在线| 精品午夜福利视频在线观看一区| 久久中文看片网| 亚洲中文日韩欧美视频| 久久精品人人爽人人爽视色| 老司机亚洲免费影院| 在线观看免费日韩欧美大片| 少妇粗大呻吟视频| 国产单亲对白刺激| 免费在线观看完整版高清| 看片在线看免费视频| 久久人妻熟女aⅴ| 午夜两性在线视频| 久久久精品国产亚洲av高清涩受| 搡老岳熟女国产| 久久人妻av系列| 日本黄色日本黄色录像| 无限看片的www在线观看| 最近最新免费中文字幕在线| 午夜视频精品福利| www国产在线视频色| 亚洲第一青青草原| 亚洲国产欧美网| а√天堂www在线а√下载| 丰满饥渴人妻一区二区三| 三级毛片av免费| 男女午夜视频在线观看| 欧美大码av| 国产午夜精品久久久久久| 国产免费男女视频| 两性夫妻黄色片| 亚洲精品在线观看二区| 亚洲男人的天堂狠狠| 国产黄a三级三级三级人| 欧美乱码精品一区二区三区| 午夜福利在线观看吧| 成人国产一区最新在线观看| 亚洲精品国产一区二区精华液| 日本精品一区二区三区蜜桃| 国产免费男女视频| 国产精品偷伦视频观看了| 成人国产一区最新在线观看| 午夜久久久在线观看| 天堂√8在线中文| 国产精品乱码一区二三区的特点 | 天堂影院成人在线观看| 午夜福利免费观看在线| 水蜜桃什么品种好| 日韩有码中文字幕| 一a级毛片在线观看| av国产精品久久久久影院| 中文字幕人妻丝袜制服| av免费在线观看网站| 热99re8久久精品国产| 一区福利在线观看| 可以在线观看毛片的网站| 18禁美女被吸乳视频| 精品国产亚洲在线| 精品久久蜜臀av无| 亚洲熟妇中文字幕五十中出 | 久久久精品欧美日韩精品| 水蜜桃什么品种好| 黄色片一级片一级黄色片| 两个人免费观看高清视频| 国产1区2区3区精品| 国产成人精品无人区| 老汉色∧v一级毛片| 国产亚洲欧美98| 亚洲av美国av| 无限看片的www在线观看| 国产精华一区二区三区| 村上凉子中文字幕在线| 9色porny在线观看| 欧美日韩乱码在线| 黑人巨大精品欧美一区二区mp4| 精品国产一区二区久久| 18禁国产床啪视频网站| 精品久久久精品久久久| 嫁个100分男人电影在线观看| 久久国产乱子伦精品免费另类| 精品第一国产精品| 国产精品自产拍在线观看55亚洲| 女同久久另类99精品国产91| 午夜老司机福利片| 国产免费av片在线观看野外av| 一区二区三区国产精品乱码| 极品教师在线免费播放| 女人爽到高潮嗷嗷叫在线视频| 国产色视频综合| 国产成人系列免费观看| 久久久久久久久免费视频了| 久久99一区二区三区| 色哟哟哟哟哟哟| 精品日产1卡2卡| 琪琪午夜伦伦电影理论片6080| 欧美精品亚洲一区二区| 人人妻人人澡人人看| 少妇被粗大的猛进出69影院| 欧美日韩国产mv在线观看视频| 国产色视频综合| 天天影视国产精品| 真人做人爱边吃奶动态| 夜夜爽天天搞| 亚洲精品在线观看二区| 精品一区二区三区av网在线观看| 日日干狠狠操夜夜爽| 自线自在国产av| 日韩欧美在线二视频| 五月开心婷婷网| 一边摸一边做爽爽视频免费| 十分钟在线观看高清视频www| 天堂√8在线中文| 精品福利观看| 性少妇av在线| 国产欧美日韩精品亚洲av| 日韩国内少妇激情av| 女警被强在线播放| 欧美午夜高清在线| 国产伦一二天堂av在线观看| 如日韩欧美国产精品一区二区三区| 国产真人三级小视频在线观看| 热re99久久国产66热| 久久精品91无色码中文字幕| 久久人人精品亚洲av| 可以在线观看毛片的网站| 最近最新免费中文字幕在线| 亚洲美女黄片视频| 久久青草综合色| 中国美女看黄片| 精品久久久久久,| 亚洲色图综合在线观看| 亚洲国产欧美一区二区综合| 亚洲少妇的诱惑av| 国产精品电影一区二区三区| 18美女黄网站色大片免费观看| 亚洲美女黄片视频|