成人小说亚洲一区二区三区,亚洲国产精品一区二区三区,国产精品成人精品久久久,久久综合一区二区三区,精品无码av一区二区,国产一级a毛一级a看免费视频,欧洲uv免费在线区一二区,亚洲国产欧美中日韩成人综合视频,国产熟女一区二区三区五月婷小说,亚洲一区波多野结衣在线

立即打開
機(jī)器人藥片有望給糖尿病患者帶來(lái)福音

機(jī)器人藥片有望給糖尿病患者帶來(lái)福音

Gerald Bernstein 2014年03月11日
它基本上是一個(gè)聚合物膠囊,里面裝著很多用糖做的微型空心針。它像普通藥物一樣口服后可安然進(jìn)入腸道。一旦進(jìn)入小腸,人體的酸性物質(zhì)就會(huì)溶解膠囊的外層,露出的微型氣球狀結(jié)構(gòu)會(huì)不斷膨脹,將裝滿藥物的針頭輕輕推進(jìn)腸壁,從而解決糖尿病治療中胰島素的用藥難題。

????皮膚。皮膚是一個(gè)堅(jiān)實(shí)致密的組織,用來(lái)保護(hù)人體免受外物傷害。雖然理論上藥物也能通過(guò)皮膚被人體攝取,但是像分子一樣大的胰島素需要電力刺激才能穿透皮膚。因此這種方法又貴又不實(shí)用。另外也有人嘗試通過(guò)用藥物舒張毛孔的方式來(lái)給藥,但是多年來(lái)毫無(wú)進(jìn)展。

????鼻粘膜。已經(jīng)有通過(guò)鼻粘膜成功使用胰島素的先例,但是對(duì)于日常使用來(lái)說(shuō),鼻粘膜還是太脆弱了。

????口腔內(nèi)壁。它也是一種有彈性的粘膜,而且也具有吸收能力(想一想咀嚼式的煙草)。把溶解狀態(tài)的胰島素通過(guò)像哮喘噴劑一樣的工具噴入口腔,已被證實(shí)是一種可以快速將胰島素吸收到血液中的方法。這也是一種很有希望的方法,目前正在美國(guó)和印度接受試驗(yàn)。

????肺。幾年前通過(guò)肺部吸收胰島素的方法被研究了出來(lái),但這種方法的隱患是,長(zhǎng)期使用可能導(dǎo)致肺部損傷。美國(guó)藥監(jiān)局(FDA)雖然批準(zhǔn)了這種方法,但要求患者必須定期接受肺功能檢查。不過(guò)由于經(jīng)濟(jì)上并不實(shí)惠,再加上醫(yī)生很少使用這種療法,導(dǎo)致這種療法最終退出了市場(chǎng)。另一種類似產(chǎn)品已經(jīng)研究了一段時(shí)間了,而且不久即將接受FDA的審查。

????既然這些方法都不管用,為什么不把胰島素做成口服藥呢?這聽(tīng)起來(lái)是個(gè)簡(jiǎn)單的答案,但實(shí)際上卻并不這么簡(jiǎn)單。首先,就像有的人有復(fù)發(fā)燒心癥狀,有的人有腸道易激綜合癥一樣,人的胃腸系統(tǒng)存在很大的個(gè)體差異。

????其次是“漢堡包綜合癥”。人吞下胰島素藥片后,它必須先經(jīng)過(guò)胃部的酸性環(huán)境的折磨,然后再在十二指腸中被消化酶“洗禮”一遍,然后再進(jìn)入腸道,最后才能進(jìn)入血液。另外胰島素還要經(jīng)過(guò)肝臟,有可能藥物還沒(méi)接觸到血液和人體組織,就已經(jīng)被肝臟破壞和分解了。

????許多藥企都嘗試過(guò)研制胰島素片劑,但最后都以失敗告終,但現(xiàn)在仍有一些制藥公司依然在鍥而不舍地研制最終能被血液吸收的口服胰島素。但我對(duì)他們的嘗試仍然持懷疑態(tài)度。

????我們?cè)倩貋?lái)看看文章開頭提到的機(jī)器人藥片。它基本上就是一個(gè)聚合物膠囊,里面裝著很多用糖做的微型空心針。膠囊像普通藥物一樣吞入腹中后,可以安然進(jìn)入腸道。一旦進(jìn)入小腸,人體的酸性物質(zhì)就會(huì)溶解膠囊的外層,露出的微型氣球狀結(jié)構(gòu)會(huì)不斷膨脹,輕輕地將裝滿藥物的針頭推進(jìn)腸壁。

????這是一個(gè)非常有趣的概念,很可能發(fā)展成一個(gè)有效的給藥系統(tǒng),但它離真正投入市場(chǎng)還有很遠(yuǎn)。它在胰島素上的應(yīng)用也仍然有待觀察。(財(cái)富中文網(wǎng))

????本文作者吉拉爾德?伯恩斯坦博士是紐約市西奈山以色列醫(yī)療中心弗里德曼糖尿病研究所糖尿病管理項(xiàng)目的主任,曾任美國(guó)糖尿病協(xié)會(huì)主席。

????譯者:樸成奎

????

????Skin.The skin is a tough, dense tissue that protects our body by keeping foreign material out. Drugs can be delivered through the skin, but a large molecule like insulin needs a supplemental electrical force to pierce the skin. This is expensive and impractical. There have been attempts to use a patch with chemicals that open the pores, but over years it has not moved forward.

????Nasal membranes.Insulin has been successfully delivered through the nasal membranes, but they are too fragile for regular use.

????Lining of the mouth.This is a resilient membrane that also has absorptive capacity (think chewing tobacco). Insulin in solution has been sprayed into the mouth using an asthma-like inhaler that enables rapid absorption into the blood stream. This is a promising avenue that is undergoing tests in the U.S. and India.

????Lungs.A few years ago delivery to and through the lungs was developed, but there are and were concerns about long-term usage and lung damage. The FDA approved it but only with regular periodic pulmonary function tests. The financial impracticality and limited prescribing led the producer to take it off the market. Another product has been under study for some time and will be reviewed by the FDA.

????So if none of these really work, why not deliver insulin in a pill? Seems like a simple answer, but it's anything but. For one thing, as anyone with recurrent heartburn, irritable bowel and the like knows, no two days in the GI tract are the same.

????Then there's the hamburger syndrome. When insulin is swallowed, it must pass through the vicious acid environment of the stomach, then through the equally vicious pool of digestive enzymes in the duodenum, then finally onto and through the lining of the intestines before it enters the bloodstream. Insulin must also pass through the liver, where it may be destroyed or sequestered before reaching the general blood flow and the body's tissues.

????Many companies have tried and failed to package insulin in a pill, and several new systems designed to protect insulin from the body are under development. I remain skeptical.

????Which brings us back to the robotic device mentioned at the start, which is basically a capsule consisting of a polymer shell and a cargo of tiny, hollow needles made of sugar. Like a typical pill, the capsule is swallowed and makes its way through the GI tract. Once it reaches the small intestine, acids in the body dissolves the outer layer of the capsule, freeing a balloonlike structure that expands and gently pushes the drug-filled needles into the wall of the intestine.

????It is an interesting concept that could have legs as a drug-delivery system, but it's a long way from market. Its application to insulin also remains to be seen.

????Dr. Gerald Bernstein is director of the Diabetes Management Program at Friedman Diabetes Institute at the Mount Sinai Beth Israel Medical Center in New York City and past president of the American Diabetes Association.

掃碼打開財(cái)富Plus App
草莓视频污污在线观看| 国产精品久久久久久久AV大片| 77色午夜成人影院综合网| 国产成人精品久久二区二区| 国产精品自在拍首页视频8| 无人区高清在线观看完整版| 国产FREEXXXX性播放麻豆| 知道你爱国产色产综合色产在线视频| 日本韩国黄色一区二区三区| 日本国产理论片午午伦夜理片| 亚洲人成网址在线播放狼友| 色视频一区二区三区网网网网 | 国产欧美日韩久久久久| 藏经阁AV无码综合亚洲| 日韩AV无码久久一区| 免费国产黄线在线观看| 无码人妻AⅤ一区二区三区日本| 亚洲精品国产精品国产| 亚洲六月丁香六月婷婷花| 亚洲欧美综合区自拍另类| 国产又粗又黄又爽又硬| 欧洲精品码一区二区三区免费看| 一级a性色生活片久久无少妇| 精品国产综合区久久久久久| 一本一道VS无码中文字幕| 午夜成人无码福利免费视频| 色欲精品国产一区二区三区AV| 在线观看午夜福利片日本| 久久99国产精品成人| 欧美精品AⅤ一区二区三区| 男人的天堂AⅤ一区二区| 国产成人猛男69精品视频| JK浴室自慰到不停喷水尿失| 国产乱婬AV片免费| 日本人成在线播放免费课体台| 久精品国产欧美亚洲色aⅴ大片| 中文字幕欧美人妻精品一区| 欲色影视天天一区二区三区色香欲| 老子午夜精品888无码不卡| 日本xXXX片免费观看国产| 久久97精品久久久久久久|