????近日，《華爾街日報》（the Wall Street Journal ）刊登的一篇文章為我們介紹了一種獨特的“機器人藥片”。它可以用來取代胰島素針劑之類的注射類藥物，減輕糖尿病等慢性病患者用藥的痛苦。

????目前這種機器人藥片尚未進行人體測試。《華爾街日報》指出，機器人藥片要獲得聯邦批準至少還得一年的時間，但是它已經贏得了很多支持者。比如硅谷的一家名叫InCube Labs的初創公司正在進行相關研發工作，谷歌創投（Google Ventures）為這個項目提供了早期投資，另外，２５００多萬名美國糖尿病患者也在翹首期盼這種藥物早日面世。

????但是機器人藥片也存在競爭對手。去年１２月，以色列的Oramed制藥公司宣布它一種尚處于試驗階段的口服胰島素藥片取得了積極的成果，一項研究“清楚地表明”，這種藥物是“安全的，而且耐受力良好。”之后這家公司的股價由６美元飆升到了３２美元。但是不久后被曝出，這個結論的基礎只是一項僅僅為期一個禮拜的測試，而且被試者只有３０人。隨后這家公司的股票立即跌回原形。

????自從９０多年前，一個加拿大醫生團隊發現了胰島素以來，大家一直沒有放棄過尋找胰島素的替代物，或者至少是一種替代性的給藥方法。胰島素雖然在治療糖尿病上有效，但它也有自己的缺點。

????胰島素就像漢堡包一樣，是一種蛋白質，因而在口服用藥中難免被分解和破壞。早在上世紀２０年代，人們就采用了注射的方式使用胰島素，每次注射完畢后都要對注射器和針頭進行消毒。早期的胰島素藥效持續的時間較短，而針頭在重復使用的過程中會變得越來越鈍，因此注射胰島素時的痛苦自不待言。

????早在１９２５年，人們就開始嘗試用其他方法攝取胰島素，但是直到現在，這種做法依然存在很高風險。胰島素的并發癥從失明、腎衰竭、足病（甚至截肢）到心血管疾病不一而足。更令人擔憂的是，肥胖和缺乏鍛煉使糖尿病的發病率呈穩步上升之勢。據美國疾病預防控制中心（to the Centers for Disease Control and Prevention）統計，超過４０%的美國人要么已經被診斷為糖尿病，要么就是前驅糖尿病（也就是雖未達到II型糖尿病標準，但存在葡萄糖代謝障礙），而且糖尿病人的數量正像傳染病一樣越來越多。

????過去９０年里，不時也會涌現出胰島素針劑的替代品，但都只是曇花一現。有效、給藥方便、同時經濟實惠的替代品直到現在也沒有被開發出來。

????為了尋找其它的給藥方法，可以說科學家們已經把人體的里里外外試了個遍。盡管人體大多數部位都不適合胰島素的給藥，但是科學家們還是在執著地探索著人體的每個面、膜、腔的給藥可能性。下面僅列舉這些年來的一些研究，排名不分先后。

????陰道。數據顯示，胰島素可以通過陰道壁吸收，但是效率較低，況且它在倫理上也不是一種可以接受的方法。

????直腸。直腸內壁也是一個很好的脈管組織，可以吸收很多藥物。但是很顯然它的局限性也使它不太可能用于日常用藥。

????A recent article in the Wall Street Journal provided a fascinating description of arobotic pill designed to replace injectable drugs like insulin that are used to treat chronic conditions like diabetes.

????The robotic pill hasn't been tested in humans, and the Journal pointed out that it is at least a year away from even seeking federal approval, but a lot of people are rooting for it. They include InCube Labs, a Silicon Valley startup that's doing the development work; Google Ventures (GOOG), which has provided early financing; and the more than 25 million Americans who currently suffer from diabetes.

????The robot has competition. The shares of one would-be competitor -- an Israeli company named Oramed Pharmaceuticals (ORMP) -- soared from $6 to $32 in December when it reported positive results for an experimental insulin pill, citing a study that "clearly shows" that the drug "is safe and well-tolerated." The stock gave back most of the gains when it turned out that results were based on a one-week test of 30 patients.

????Here's the thing. Everyone and his brother have been looking for a substitute for -- or an alternate way to deliver -- insulin, almost from the day it was discovered by a team of Canadian doctors more than 90 years ago. It does the job, but it has drawbacks.

????Insulin is a protein, like hamburgers, and as such is digested and destroyed when swallowed. Back in the 1920s, it was injected using a glass syringe with a steel needle that had to be sterilized after every use. Early insulin was short-acting, reusable needles were never as sharp as during their first use, and injections were painful. It was a brutal, unsophisticated experience.

????As early as 1925, attempts were made to find other ways to get insulin into the body. Then as now, the stakes were high: Complications from diabetes range from blindness and kidney failure to limb loss and cardiovascular disease. To make things worse, the lack of exercise and growing obesity are fueling a steady increase in diabetes. According to the Centers for Disease Control and Prevention, more than 40% of the U.S. population has either clinical diabetes or prediabetes, and the numbers are growing at what the CDC calls epidemic proportions.

????Substitutes for insulin injections have regularly appeared during the past 90 years, but so far an acceptable answer -- one that is effective, easily delivered and economically feasible -- has not been developed.

????The search for alternative delivery routes has involved the entire body. Although inhibitors at most sites preclude their use for insulin, every surface, membrane, and cavity has been explored as a possibility. In no special order, here are a few that have been studied over the years:

????Vagina.Data show that insulin can be absorbed through the vaginal wall, but it's an inefficient and socially unacceptable method.

????Rectum.The rectal lining is a good vascular tissue and will absorb many drugs, but obvious limitations make this site unlikely for regular daily use.