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   150296篇
  免费   32456篇
  国内免费   2419篇
耳鼻咽喉   5167篇
儿科学   5359篇
妇产科学   2392篇
基础医学   3232篇
口腔科学   1507篇
临床医学   26580篇
内科学   47631篇
皮肤病学   7435篇
神经病学   14819篇
特种医学   6446篇
外科学   41037篇
综合类   233篇
现状与发展   72篇
预防医学   6980篇
眼科学   3344篇
药学   965篇
中国医学   14篇
肿瘤学   11958篇
  2024年   685篇
  2023年   4779篇
  2022年   1185篇
  2021年   3058篇
  2020年   6017篇
  2019年   2142篇
  2018年   7361篇
  2017年   7317篇
  2016年   8405篇
  2015年   8400篇
  2014年   15485篇
  2013年   15594篇
  2012年   5454篇
  2011年   5492篇
  2010年   10353篇
  2009年   14240篇
  2008年   5797篇
  2007年   4051篇
  2006年   6526篇
  2005年   3845篇
  2004年   3100篇
  2003年   2066篇
  2002年   2163篇
  2001年   3802篇
  2000年   3011篇
  1999年   3225篇
  1998年   3669篇
  1997年   3495篇
  1996年   3391篇
  1995年   3231篇
  1994年   1959篇
  1993年   1593篇
  1992年   1397篇
  1991年   1423篇
  1990年   1068篇
  1989年   1194篇
  1988年   1028篇
  1987年   863篇
  1986年   890篇
  1985年   719篇
  1984年   556篇
  1983年   526篇
  1982年   515篇
  1981年   410篇
  1980年   370篇
  1979年   315篇
  1978年   341篇
  1977年   407篇
  1975年   284篇
  1972年   314篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
BACKGROUND: A common problem facing patients suffering from psoriasis is the need for surgery that requires incision through active psoriatic skin. Many patients have been denied surgery because of the fear of an increased risk of infection, decreased wound healing ability, and worsening of the psoriatic lesions. OBJECTIVE: To assess the practices and beliefs of dermatologists and surgeons (orthopedic and plastic surgeons) faced with the decision of whether to operate through active psoriatic skin. METHODS: Dermatologists, orthopedic surgeons, and plastic surgeons selected from various professional membership lists from five representative cities were sent a survey to ascertain their opinions on operating on active psoriatic skin. Psoriatic patients were also given forms asking about the severity of their psoriasis and whether they had ever been denied surgery. RESULTS: Dermatologists are more likely to condone surgery in active psoriatic skin and to believe that there is not a risk of increased infection or decreased wound healing than are orthopedic surgeons and plastic surgeons. These findings are statistically significant (P<0.05). CONCLUSION: With proper preoperative measures and dermatologic treatment, surgery can be performed on active psoriatic skin in most cases with minimal reservations, although a controlled, prospective study is necessary to arrive at a definitive conclusion.  相似文献   
992.
The purpose was to investigate experienced loneliness among the elderly. The material included 1725 people, aged 75 and over. The study describes relationships between loneliness, social network, cognitive function and health. Thirty-five per cent experienced loneliness, and a higher percentage was found among women. A gradual increase in loneliness was found up to the age of 90, after which a levelling was found. Elderly persons living together with a partner experienced less loneliness. There were no significant differences between those with and without children. Ten per cent reported not having any friends and, of these, one out of two experienced loneliness. A high frequency of experienced loneliness was found among elderly people with reduced cognitive function. Subjectively experienced bad health and loneliness were strongly related to each other, i.e. a person who experienced loneliness did usually not feel completely healthy.  相似文献   
993.
994.
The influence of experimentally induced hepatic dysfunction on the pharmacokinetics of Cyclosporine A (CsA) was determined in dogs. The pharmacokinetics of oral (PO) and intravenous (IV) CsA were studied before and after 70 per cent hepatectomy or complete bile duct ligation (CBDL). Changes in liver function were monitored by serial measurements of serum bilirubin, and by the maximum removal rate (Rmax) and plasma disappearance rate (ICG-K) of indocyanine green (ICG). Concentrations of CsA in whole blood were measured by HPLC. Seventy per cent hepatectomy caused significant liver dysfunction: the ICG-Rmax decreased by 47.7±7.1 per cent (mean±SD) and the ICG-K decreased by 61.3±9.7 per cent during the first week after hepatectomy. At the same time, the systemic clearance (CLs) of IV-CsA decreased by 43.9±8.2 per cent, the area under the concentration curve (AUC) of IV-CsA increased by 35.4±20.8 per cent and the bioavailability of CsA decreased by 26.4±14.8 per cent. CBDL also induced significant liver dysfunction: the ICG-Rmax decreased by 39.1±12.8 per cent and the ICG-K decreased by 65.6±3.6 per cent in the second week after the operation. During the same period, the AUC of PO-CsA decreased by 69.9±10.7 per cent and the bioavailability of CsA also decreased markedly by 73.9±15.6 per cent. These data indicate that hepatic impairment significantly influences the pharmacokinetics of CsA, not only by the changes in intestinal absorption, but also by those in hepatic, metabolism. Dose adjustment is therefore necessary in the presence of hepatic dysfunction in order to maintain an adequate blood concentration of CsA without causing side effects. This research was performed in the Department of Surgery, University of Pittsburgh Health Center, University of Pittsburgh, USA  相似文献   
995.
996.
Identification of Alcohol Abuse and Alcoholism with Biological Parameters   总被引:3,自引:0,他引:3  
The prevalence and incidence of heavy alcohol consumption are major problems which have been increasing in many countries in recent years. It is crucial for physicians to consistently identify early drinking problems as well as the various end disease states in order to minimize suffering and maximize recovery. This paper reviews the evolutionary development of clinical tools for detection of alcohol abuse. The focus is primarily on clinical/biochemical indicators of alcohol abuse, emphasizing but not limited to changes in hematological characteristics, liver enzyme activity, lipids, immune function factors, hormones, neurological factors, and some physically based tests. Use of test combinations and sophisticated statistical analysis of pattern changes in test batteries evidence increased diagnostic efficiency.  相似文献   
997.
998.
999.
The ratio of PaO2 to FiO2 was often low (300 or less) in four patients with complications of hyperosmolar hyperglycemic non-ketotic diabetic coma (HHNKDC) following open heart surgery. Four of our patients had poor oxygenation and subsequent spontaneous recovery from in the immediate post-operative period, although HHNKDC occurred only in one during this period. In the 3 others, poor oxygenation without accompanying HHNKDC lasted for 1–6 days and HHNKDC developed about 2 weeks after open heart surgery at time when poor oxygenation reoccurred. If a working diagnosis of congestive heart failure was made only on the basis of the most common probability, and the fluid supply was restricted, HHNKDC would readily occur or be aggravated by the dehydration iatrogenically produced. It is thus concluded that HHNKDC should be included in diagnoses for pulmonary dysfunction.  相似文献   
1000.
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