首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1172篇
  免费   84篇
  国内免费   4篇
耳鼻咽喉   3篇
儿科学   64篇
妇产科学   58篇
基础医学   133篇
口腔科学   33篇
临床医学   131篇
内科学   188篇
皮肤病学   26篇
神经病学   84篇
特种医学   35篇
外科学   95篇
综合类   30篇
预防医学   198篇
眼科学   33篇
药学   69篇
中国医学   4篇
肿瘤学   76篇
  2022年   9篇
  2021年   22篇
  2020年   16篇
  2019年   12篇
  2018年   21篇
  2017年   14篇
  2016年   20篇
  2015年   13篇
  2014年   27篇
  2013年   40篇
  2012年   33篇
  2011年   37篇
  2010年   32篇
  2009年   26篇
  2008年   49篇
  2007年   58篇
  2006年   30篇
  2005年   49篇
  2004年   33篇
  2003年   45篇
  2002年   36篇
  2001年   35篇
  2000年   35篇
  1999年   37篇
  1998年   15篇
  1997年   21篇
  1996年   25篇
  1995年   20篇
  1994年   11篇
  1993年   12篇
  1992年   29篇
  1991年   35篇
  1990年   25篇
  1989年   38篇
  1988年   35篇
  1987年   19篇
  1986年   26篇
  1985年   16篇
  1984年   15篇
  1983年   16篇
  1982年   13篇
  1981年   16篇
  1980年   9篇
  1979年   18篇
  1978年   11篇
  1974年   10篇
  1973年   13篇
  1971年   7篇
  1970年   10篇
  1969年   12篇
排序方式: 共有1260条查询结果,搜索用时 15 毫秒
1.
Despite growing concern with rural elderly populations, little attention has focused on their mental health, ways it may correlate with physical health, or how rural mental health patterns compare to urban. Popular wisdom contends that elderly people in general, and rural elderly persons in particular, are at increased risk for mental illness. This article examines these questions. A review of available literature suggests that elderly people may be at only slightly greater risk of mental illness than the population at large, though there are some indications that rates of depression may be somewhat higher among the elderly population. Much of this same literature implies that objective environmental conditions play a significant role in the incidence of depression. Analysis of data gathered in a statewide random poll (N = 743) indicates that while physical health tends to be poorer among rural populations, when health is held constant there is actually an inverse relationship between age and depression. Therefore, rural elderly persons are no more likely to be depressed than their urban counterparts despite harsher living conditions. Both conceptual and policy implications are discussed.  相似文献   
2.
The sudden appearance of multiple keratoacanthomas in a patient who has sustained a thermal burn is extremely uncommon. This case report describes a sixty-four-year-old man who noted multiple keratoacanthomas within three weeks after being involved in a gasoline explosion. Multiple keratoacanthomas appear to be a rare complication of thermal cutaneous injury in predisposed persons.  相似文献   
3.
4.
Isozyme variation of the Simulium damnosum sibling species complex was studied by cellulose acetate electrophoresis (CAE) from four Kenyan river systems. Two enzymes, PGM and HK, were diagnostic and differentiated the larvae collected in Western and Nyanza provinces from the larvae collected at Mt. Kenya. Allele frequency differences of the enzyme PGI allowed about 75% separation of the geographically distinct populations.  相似文献   
5.
The use of laparoscopic surgical techniques is now being applied to a variety of operations traditionally performed in an open fashion. Twenty patients underwent laparoscopic-guided large and small bowel surgery at our institution from March 1991 to April 1992. The indications for surgery included polyps, obstruction, bleeding, and perforation, and pathologic diagnoses included benign polyps, lipomas, inflammatory bowel disease, perforation of a jejunal diverticulum, colonic arteriovenous malformations, and adenocarcinoma. Mobilization of the colon, ligation of the mesentery, and closure of the mesenteric defect were performed using the laparoscopic equipment. One trocar site was enlarged to 3 cm to deliver the bowel through the abdominal wall. All anastomoses were hand-sewn. Postoperative hospitalization ranged from 2 to 31 days (median, five days). No mortality was noted, and morbidity was 20 percent. We conclude that laparoscopic-guided bowel surgery is technically feasible and should translate into shorter hospitalization and less patient discomfort.  相似文献   
6.
The author discusses the planning and development of a unique method of reaching African American clients by Chi Eta Phi Sorority, Inc. members in the state of South Carolina through use of beauty shops and barber shops, which is termed Hair Care Centers. Using bulletin boards which are placed in these establishments, the members of Chi Eta Phi Sorority, Inc. change the educational materials monthly based on the minority health awareness themes created by the Office of Minority Health in Washington, DC. The goal of Project F-HC is to take self-care, health promoting, disease prevention information to places where persons frequent, making it easily accessible.  相似文献   
7.
The primary goal of this study was to identify secondary functional changes in the peripheral motor units of the paretic upper extremity (UE) in patients with severe ischemic stroke and to determine how these changes develop during the first weeks after stroke. An inception cohort of 27 consecutive patients with an acute ischemic supratentorial stroke and an initial UE paralysis was compared with 10 healthy control subjects. The ulnar nerve was electrically stimulated proximal to the wrist and electromyographic recordings were obtained from the abductor digiti minimi muscle. Hemiparetic side mean values of the compound muscle action potential (CMAP) 1 and 3 weeks after stroke were compared with the nonparetic side and with CMAP values obtained from healthy control subjects. The mean CMAP amplitude in patients was significantly lower on the paretic side compared with the nonparetic side and with control subjects. Decrease in CMAP amplitude was observed in more than half of the stroke patients, sometimes as early as 4 days after stroke, and persisted in most cases. Whenever present, it was accompanied by absence of motor recovery at that specific time after stroke. Decreased CMAP amplitude in the abductor digiti minimi muscle can be seen already in the very acute phases after stroke unrelated to peripheral neuropathy, radiculopathy, or plexopathy, and it is accompanied by absence of UMN recovery. This knowledge is important for interpreting electrophysiological data in stroke patients.  相似文献   
8.
9.
This study investigated the effect of dehydration on measurements of body composition by hydrostatic weighing (HW) and bioelectric impedance analysis (BIA). Ten endurance-trained male athletes between the ages of 18 and 42 years performed an endurance training session consisting of running until body weight was reduced by approximately 3%. Body composition was determined prior to exercise and immediately after exercise by HW and BIA techniques. A high correlation existed between pre- and postdehydration for both HW and BIA. Validity coefficients between HW and BIA were moderate (predehydration 0.85 and postdehydration 0.82). In addition, BIA percent fat was 3.5% higher than HW percent fat. The BIA revealed a mean loss of 2.1% fat BIA and only 0.9% fat HW after approximately 45 minutes of exercise. BIA also showed an increase in percent body water (mean = 2.6%) in all 10 subjects after dehydration. There are indications that BIA, with its present equational configuration, is measuring something other than lean body weight. J Orthop Sports Phys Ther 1989;10(11):451-455.  相似文献   
10.
乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号