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   398260篇
  免费   36541篇
  国内免费   27161篇
耳鼻咽喉   3620篇
儿科学   4993篇
妇产科学   5711篇
基础医学   45703篇
口腔科学   6687篇
临床医学   55719篇
内科学   57314篇
皮肤病学   3875篇
神经病学   20643篇
特种医学   14321篇
外国民族医学   225篇
外科学   37833篇
综合类   67658篇
现状与发展   93篇
一般理论   24篇
预防医学   27716篇
眼科学   11261篇
药学   41938篇
  471篇
中国医学   24205篇
肿瘤学   31952篇
  2024年   1330篇
  2023年   6065篇
  2022年   15644篇
  2021年   19742篇
  2020年   14909篇
  2019年   12903篇
  2018年   13384篇
  2017年   12300篇
  2016年   11431篇
  2015年   17602篇
  2014年   21888篇
  2013年   20103篇
  2012年   29570篇
  2011年   32793篇
  2010年   21496篇
  2009年   17123篇
  2008年   22325篇
  2007年   22146篇
  2006年   21574篇
  2005年   20444篇
  2004年   13282篇
  2003年   12085篇
  2002年   10319篇
  2001年   8944篇
  2000年   9401篇
  1999年   9715篇
  1998年   5822篇
  1997年   5844篇
  1996年   4606篇
  1995年   4126篇
  1994年   3433篇
  1993年   2228篇
  1992年   2914篇
  1991年   2501篇
  1990年   2193篇
  1989年   1931篇
  1988年   1620篇
  1987年   1388篇
  1986年   1142篇
  1985年   942篇
  1984年   541篇
  1983年   378篇
  1982年   250篇
  1981年   247篇
  1980年   192篇
  1979年   223篇
  1977年   94篇
  1974年   107篇
  1973年   86篇
  1972年   86篇
排序方式: 共有10000条查询结果,搜索用时 12 毫秒
991.
According to our supposition that "humoral mechanism" plays an important role in the pathogenesis of portal hypertension due to cirrhosis, antagonists to some of humoral substances would lower the portal pressure in cirrhotic patients. Wedged hepatic venous pressure (WHVP) was used as an indicator for changes of portal pressure. Cimetidine was given intravenously to 8 cirrhotic patients, in whom an average lowering of 0.72 kPa (7.3 cm H2O) of WHVP was observed subsequently. This change was of clinical significance as compared with the previous results of splenorenal shunting operations.
  相似文献   
992.
感染伯氏疟原虫(P.berghe ANKA株)小鼠,经矿泉“851”及与抗疟酮合用治疗后,腹腔巨噬细胞吞噬百分率和吞噬指数明显高于感染对照组(P<0.01)。两组药均能提高小鼠单核巨噬细胞系统(MPS)对碳微粒的廓清率,其K值与对照组相比,P<0.01,MPS活性的增强程度与其疟原虫的抑制率成正相关。  相似文献   
993.
994.
OBJECTIVE: This study longitudinally described rates of posttraumatic stress disorder (PTSD) in two groups with different levels of severity of exposure to an earthquake in North China. The effects of diagnostic criteria on the frequency of detected PTSD were also examined. METHOD: Subjects were randomly sampled in two villages at different distances from the earthquake epicenter. A total of 181 and 157 subjects were assessed at 3 months and 9 months after the earthquake, respectively, for PTSD by using both DSM-IV and DSM-III-R criteria. The brief version of the World Health Organization Quality of Life Assessment and three subscales of the SCL-90-R were also administered at both assessment points. RESULTS: The village with a higher level of initial exposure to the earthquake and a higher level of postearthquake support had a lower frequency of PTSD than the village with a lower level of initial exposure and less postearthquake support. The rate of onset of DSM-IV PTSD within 9 months for the two villages was 19.8% and 30.3%, respectively. In both villages, the rate of onset of earthquake-related PTSD within 9 months was 24.2% by using DSM-IV criteria and 41.4% by using DSM-III-R criteria. The introduction in DSM-IV of a criterion requiring clinically significant distress or impairment in functioning for a diagnosis of PTSD was a major contributor to the lower rate of DSM-IV PTSD. CONCLUSIONS: PTSD may be as prevalent and persistent in disaster victims in China as in those elsewhere. Prompt and effective postdisaster intervention could mitigate the impact of initial exposure and reduce the probability of PTSD occurrence. Caution should be used in comparing rates of postdisaster PTSD identified by using different diagnostic criteria.  相似文献   
995.
996.
Objective: The symptoms of depression experienced by women during the postnatal period may have profound effects on the lifelong health of both the mother and the child. In this randomized controlled study, we systematically evaluated the effects of weekly supportive group meetings for women with postnatal distress. Methods: Sixty postnatally distressed women were randomly assigned to support (n=30) and control (n=30) groups. Women assigned to the support group participated in four supportive group sessions that comprised discussions concerning transition to motherhood, postnatal stress management, communication skills, and life planning. Results: Subjects who attended the support sessions had significantly decreased scores on the Beck Depression Inventory (BDI) and the Perceived Stress Scale (PSS), and significantly increased scores on the Interpersonal Support Evaluation List (ISEL) as evaluated at the end of the fourth weekly session. In contrast, no significant changes were observed in the control group during this period. Conclusion: This is the first controlled study to provide evidence that participation in support groups for postnatally distressed women provides quantifiable psychosocial benefits.  相似文献   
997.
BACKGROUND AND PURPOSE: Since the FDA approved tissue plasminogen activator (tPA) in 1996 for acute ischemic stroke, few data have been obtained during the postmarketing phase, and applicability in rural hospitals does not exist. We attempt to examine the safety and outcome of intravenous tPA for acute ischemic stroke in the OSF Stroke Network. METHODS: Fifty-seven consecutive patients treated with tPA were examined from June 1996 through December 1998. Admission and discharge National Institute of Health Stroke Scales (NIHSS), modified Rankin Scales (MRS), and discharge disposition, as well as intracerebral hemorrhage and mortality rates, were compared. RESULTS: Of 20 network hospitals, 12 had the experience of administering tPA. No statistically significant differences in the variables recorded were observed for patients treated at the community hospitals versus those who received tPA at the tertiary medical center. In 35% of patients, tPA was initiated by an emergency room or primary care physician in consultation with an OSF neurologist. At discharge, 47% of the patients had minimal or no disability (MRS, 0 to 1), 44% had an NIHSS score of 0 or 1, 54% went home, 25% were transferred to in-patient rehabilitation, 12% went to a nursing or skilled-care facility, and 9% died. Intracerebral hemorrhage rate was 9%; 5% were symptomatic. CONCLUSIONS: tPA can be administered safely with good outcome at community and rural hospitals. The OSF Stroke Network can serve as a model to assist small community hospitals to set up stroke programs and deliver up-to-date, acute stroke therapies.  相似文献   
998.
999.
Researchers from Japan, China and Singapore have initiated a collaborative project, with the aim of comparing adolescent quality of life (QOL) internationally. This study presents the primary results of the investigation conducted in Beijing, China, and Kobe, Japan. The 70-item Quality of Life Questionnaire for Adolescents (QOLQA) was developed and evaluated in Japan and China. In total, 1114 Japanese and 613 Chinese junior high school students, aged 12-15 years, completed the questionnaire. Chinese students scored significantly higher than the Japanese students in overall QOL scores and in most domains. For both groups, subjects had highest score in the independence domain and lowest in psychological domain. In terms of overall QOL score, Chinese male students ranked first, followed by Chinese girls, Japanese boys, and Japanese girls. In the Japanese group, a continuing decrease of QOL scores with age was observed without exception, but no such tendency was present in their Chinese counterparts. No parallel relationship was observed between the higher level of economic development and better quality of life. The results also suggest that mental health promotion should be a priority in improving overall quality of life of adolescents both in Japan and China.  相似文献   
1000.
Liu HM  Huang YC  Wang YH  Tu YK 《Neuroradiology》2000,42(10):766-770
We report the effectiveness of low-concentration n-butyl-2-cyanoacrylate (NBCA)-Lipiodol-tungsten mixture (10–15 %) in the management of patients with aggressive or recurrent complex cavernous dural arteriovenous fistulae (CSDAVF). We treated five patients with complex CSDAVF with a low concentration of an NBCA-Lipiodol-tungsten mixture after catheterisation of the feeding arteries arising from the external carotid artery. Three had a recurrent CSDAVF after transarterial particulate embolisation. Three refused transvenous treatment or could not be treated in this way; two patients had also feeding dural branches of the internal carotid artery. All patients had complete resolution of symptoms and signs within a month of the procedure. No definite neurological complication was found during follow-up ranging from 12 to 36 months. Transarterial embolisation with low-concentration cyanoacrylate appears to be an effective alternative management of aggressive or recurrent CSDAVF. Received: 8 November 1999/Accepted: 2 March 2000  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