问题 多项选择题

病历摘要:患者女,36岁,主诉20年前因妊娠后发现右耳听力差,伴轰鸣,已在医院检查耳膜增厚,混浊,稍内陷,经耳咽管吹张治疗似有好转,但进步不明显,因尚不影响社交活动而未进行治疗。10年前因上感后觉左耳听力亦下降,伴蝉鸣,有时轻度眩晕。因症状持久不愈,听力下降影响工作,前来就诊,据家人说,幼年曾有耳流脓历史,记事后未再流脓,姑母听力亦不好。当时,患者言语轻柔,双耳膜完整,较菲薄,右耳膜前上有小钙化斑不内陷,Siegle’s耳镜检查,鼓膜活动度好,音叉检查:C256Weber’stest居中,Rinnee’stest双耳骨导大于气导。Schwabach’stest双耳均延长。

提示:根据病史及音叉检查,诊断传导性耳聋。 提问:为进一步寻觅何种病因引起传导性聋,尚需哪些检查()?

A.头颅X线检查,照Schueller氏位及Mayer氏位像

B.声导抗测听

C.音叉试验中需补充Gelle’test

D.纯音听阈测定

E.重振试验:ABLB,Sisi,DL(响度辨差阈)

F.脑干电反应测听(ABR)

G.Bekesy自描听力测验

H.纤维鼻咽镜检查

答案

参考答案:B, C, D

解析:

此问有8项备选答案,其中第2,3,4项是正确的。根据病史及音叉检查初步诊断为传导性聋。在声导抗测听检查中示:鼓室图为As型,鼓膜静态声顺值偏低,在纯音听力计测验示有传导性耳聋的患者中,声顺的高低对鉴别听骨链中断和耳硬化症都有一定的参考价值。音叉试验中需补充Gelle’stest,这是测验镫骨有无固定的一种方法。随着耳道内的压力增加,将镫骨底板推向前庭窗内使传声功能受影响,以致音叉音明显减弱,停止加压时,音叉音又增加,是为阳性,若耳硬化症镫骨已固定,外耳道内的压力增加镫骨不内移,音叉音将无明显改变,是为测验阴性。此试验,测定镫骨是否固定,对决定手术类型,判断预后均十分重要。第5,6,8项备选答案与本病无关,是不正确的。第1,7项可做可不做的检查,意义不大,故作为无效答案。

单项选择题
问答题

There’s a human liver sitting in a lab dish in Madison, Wis. Also a heart, a brain and every bone in the human body even though the contents of the dish are a few cells too small to be seen without a microscope. But these are stem cells, the most immature human cells ever discovered, taken from embryos before they had decided upon their career path in the body. (46) If scientists could only figure out how to give them just the right kick in just the right direction, each could become a liver, a heart, a brain or a bone. (47) When a team from the University of Wisconsin announced their discovery, doctors around the world looked forward to a new era of medicine one without organ-donor shortages or the tissues-rejection problems that bedevil transplant patients today.

Doctors also saw obstacles, though. One of them was a U. S. Congress skittish about research on stem cells taken from unwanted human embryos and aborted fetuses. Indeed, 70 lawmakers asked in a firmly worded letter that the Federal Government ban all such work.

Yet the era of "grow your own" organs is already upon us, as researchers have sidestepped the stem cell controversy by making clever use of ordinary cells. Today a machinist in Massachusetts is using his own cells to grow a new thumb after he lost part of his chest wall in an accident. A teenager born without half of his chest wall is growing a new cage of bone and cartilage within his chest cavity. Scientists announced that bladders, grown from bladder cells in a lab, have been implanted in dogs and are working. Meanwhile, patches of skin, the first "tissue-engineered" organ to be approved by the U. S. Food and Drug Administration, are healing sores and skin ulcers on hundreds of patients across the U. S.

How have scientists managed to do all this without those protean stem cells Part of the answer is smart engineering. (48) Using materials such as polymers with pores no wider than a toothbrush bristle, researchers have learned to sculpt scaffolds in shapes into which cells can settle. The other part of the answer is just plain cell biology. (49) Scientists have discovered that they don’t have to teach old cells new tricks; given the right framework and the right nutrients, cells will organize themselves into real tissues as the scaffolds dissolve. "I’m a great believer in the cells. They’re not just lying there, looking stupidly at each other," says Francois Auger, an infectious disease specialist and builder of artificial blood vessels at Laval University in Quebec City. "They will do the work for you if you treat them right."

Replacement hearts—or even replacement heart parts—are at least a decade off, estimates Kiki Hellman, who monitors tissue-engineering efforts for the FDA. "Any problem that requires lots of cell types ’talking’ to one another is really hard," she notes. Bone and cartilage efforts are much closer to fruition, and could be ready for human trials within two years. (50) And what of those magical stem cells that can grow into any organ you happen to need—if the law and biologists’ knowledge permit "Using them," says Sefton, "is really the Holy Grail.

(46) If scientists could only figure out how to give them just the right kick in just the right direction, each could become a liver, a heart, a brain or a bone.