As the season of sneezing and grabbing tissues begins with the autumn's first frosts, medical researchers have found that "granny's nostrums" to fend off colds may be scientifically proven.

    Although apparently common sense, straightforward connections between chilling and viral infection have been hard to prove, according to the common cold centre at Cardiff University--the world's only centre dedicated to researching and testing new medicines for the treatment of flu and the common cold.

    But the latest experiment reinforces theories that existing, latent infection can be activated when parts of the body, particularly the feet and nose, get wet and cold.

    All participants took off their shoes and socks and temperatures were monitored throughout the experiment.

    Ninety volunteers who spent 20 minutes with their feet in bowls of iced water have provided evidence that failing to wrap up warmly is directly linked to falling prey to sore throats and a bunged-up nose.

Claire Johnson and Ron Eccles found that 29% of the volunteers developed cold symptoms within five days.

    "When colds are circulating, many people are mildly infected but show no symptoms," said Professor Eccles, whose findings are published in today's issue of Family Practice magazine.

    "But if they become chilled, this causes a pronounced constriction of the blood vessels in the nose and shuts off the warm blood that supplies the white cells that fight infection. "

    "Although the chilled subject believes they have 'caught a cold', what has in fact happened is that the dormant infection has taken hold."

    But they also suggested that another explanation could be that our noses are colder in the winter. Prof Eccles said: "A cold nose may be one of the major factors that causes common colds to be seasonal."

    "When the cold weather comes we wrap ourselves up in winter coats to keep warm but our nose is directly exposed to the cold air. Cooling of the nose slows down clearance of viruses from the nose and slows down the white cells that fight infection."

    The researchers said:" Parents should feel confident in telling children to wrap themselves up in those nose-protecting garment this winter."

    冬天已經(jīng)悄然來臨，這也意味著又到了人們頻繁打噴嚏和流鼻涕的季節(jié)了。醫(yī)學(xué)研究人員近日表示，他們發(fā)現(xiàn)那種把身體包裹得密不透風(fēng)來抵御感冒的傳統(tǒng)方法是有科學(xué)意義的。

    目前世界上唯一一個專門研究和檢測各種用來治療流感及普通感冒的藥物的研究機構(gòu)——英國加的夫大學(xué)普通感冒研究中心的科研人員表示，盡管多穿衣服可防感冒早已成為常識，但科學(xué)家們卻一直很難證明在身體著涼與病毒感染之間存在著直接的聯(lián)系。

    但他們最新進(jìn)行的實驗表明，當(dāng)身體的某些部位（尤其是雙腳和鼻子）處于潮濕冰涼的環(huán)境里時，原本處于潛伏期的病毒感染會變得活躍起來。

    在實驗中，所有參與者都脫下鞋子和襪子，而空氣溫度也受到了全程監(jiān)控。

    90個志愿者將自己的雙腳放到了盛滿冰水的盆中，并在里面堅持了20分鐘。實驗結(jié)果充分證明，如果一個人沒有使自己的身體完全處于溫暖狀態(tài)下的話，則可以直接導(dǎo)致咽喉腫痛與鼻塞。

    克萊爾·約翰遜和羅恩·埃克勒斯發(fā)現(xiàn)，29％的腳踏冰水的志愿者在此之后的5天內(nèi)出現(xiàn)了感冒癥狀。

    埃克勒斯教授的相關(guān)研究成果已經(jīng)刊登在今天出版的《家庭實踐》雜志上。他表示：“當(dāng)冷空氣處于循環(huán)流動狀態(tài)下時，很多人會輕微感染上各種感冒病毒，但并未表現(xiàn)出任何癥狀。 ”

    “但如果一個人已經(jīng)明顯感到寒意的話，那么其鼻子內(nèi)的血管會發(fā)生明顯的收縮，此舉可阻斷那些攜帶有白血球的溫暖血液的前進(jìn)道路，而白血球正好可以消滅那些感冒病毒。”

    “盡管那些被凍著的人認(rèn)為自己此時剛剛?cè)旧细忻埃�但實際情況卻是其體內(nèi)原先處于潛伏狀態(tài)的病毒開始發(fā)威了。”

    但研究人員也提到了對此的另外一種解釋，那就是我們的鼻子的溫度在冬天會變得較之其它季節(jié)更低一些。埃克勒斯教授說：“較冷的鼻子或許是導(dǎo)致普通感冒成為季節(jié)性疾病的一個主要原因。”

    “在冬季到來時，我們會用厚厚的冬衣驅(qū)寒保暖，但卻常常將自己的鼻子直接暴露在寒冷的空氣中。鼻子著涼使得白血球無法及時投入與感冒病毒作戰(zhàn)的主戰(zhàn)場，從而延緩了對那些病毒的清除。”

    研究人員表示，父母們完全可以滿懷信心地告訴孩子們，冬天應(yīng)當(dāng)多穿些能使鼻子得到充分保護的衣服。