The epidemiology of physician learning

Because medicine and education share a striking number of attributes, the authors explored epidemiology-a tool useful in medicine-as a perspective on the education of physicians. More specifically, the parallel between medicine and education was examined, key features of epidemiology were identified, and these were used in exploring attributes of the continuing education of physicians. This exploration involved both a regional study of primary care physicians for adults and a national study of a single specialty.     

一阶导数光谱法测定复方红甲凝胶中乳糖酸红霉素的含量

建立测定复方红甲凝胶中乳糖酸红霉素的含量测定方法。方法：以一阶导数光谱的谷一零位值法测定乳糖酸红霉素的含量,测定波长λ谷=490±lnm。结果：回收率100.6％,RSD为3.1％,线性范围40～120μg／ml。结论：方法简便,结果准确,重现性好,适合于该制剂的含量测定。     

几种伪随机序列应用于诱发电位检测的性能比较

伪随机序列技术作为一种快速检测诱发电位的技术已得到重视。本文主要对几种常用序列Ｍ序列、巴克序列和格雷互补序列等应用于诱发电位检测时的性能进行研究，分别给出了它们的解卷积算法及用于诱发电位检测时相对于平均法的信噪比改善倍数。理论及实验表明，Ｍ序列在检测信噪比改善方面较另两种序列好。     

Percutaneous transluminal dilatation of the iliac artery: long-term results

One hundred fifty-four patients with stenosis of the iliac artery underwent percutaneous transluminal angioplasty (PTA). These patients were followed for 1-7 years. The long-term results of the PTAs were analyzed by computer, and life tables were generated for dilatations of the iliac arteries with unimpaired flow and for those with an obstruction in the outflow tract. The accumulative 7-year patency rate was 90%, which agrees with other reports. This study demonstrates that the long-term results of PTA of iliac arterial stenoses are competitive with reconstructive vascular surgery. PTA should be the treatment of choice in patients with iliac arterial stenoses.     

Transluminal angioplasty evaluated by electron microscopy

To gain more understanding about the changes that follow balloon angioplasty, an electron and light microscopic study was carried out in normal canine arteries. Thirty-five arterial segments were dilated with balloon catheters. Early changes consisted of denudation of the intima with widespread necrosis of myocytes and dehiscence of collagen fibers. After three days, myocytes had disappeared leaving empty spaces and edematous ground substance. After two weeks, reendothelization occurred and there was evidence of intimal hyperplasia persisting up to two months. Repair of the dilated arterial segments occurred by proliferation of myocytes, formation of intima, and proliferation of collagen. In two to three months, repair of the intima and media was completed. After six months, dilated segments were characterized by persistent intimal hyperplasia and increased collagen content in the media.