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   19162篇
  免费   1671篇
  国内免费   37篇
耳鼻咽喉   130篇
儿科学   717篇
妇产科学   540篇
基础医学   2479篇
口腔科学   233篇
临床医学   2224篇
内科学   3705篇
皮肤病学   315篇
神经病学   2011篇
特种医学   358篇
外国民族医学   5篇
外科学   2097篇
综合类   163篇
一般理论   68篇
预防医学   2835篇
眼科学   275篇
药学   1208篇
  1篇
中国医学   38篇
肿瘤学   1468篇
  2024年   43篇
  2023年   285篇
  2022年   506篇
  2021年   949篇
  2020年   569篇
  2019年   781篇
  2018年   889篇
  2017年   651篇
  2016年   651篇
  2015年   714篇
  2014年   932篇
  2013年   1199篇
  2012年   1673篇
  2011年   1685篇
  2010年   869篇
  2009年   704篇
  2008年   1181篇
  2007年   1242篇
  2006年   1005篇
  2005年   946篇
  2004年   847篇
  2003年   763篇
  2002年   573篇
  2001年   94篇
  2000年   94篇
  1999年   80篇
  1998年   126篇
  1997年   86篇
  1996年   54篇
  1995年   63篇
  1994年   54篇
  1993年   52篇
  1992年   46篇
  1991年   41篇
  1990年   30篇
  1989年   38篇
  1988年   17篇
  1987年   24篇
  1986年   47篇
  1985年   31篇
  1984年   30篇
  1983年   12篇
  1982年   14篇
  1981年   19篇
  1980年   19篇
  1979年   11篇
  1978年   22篇
  1977年   13篇
  1976年   13篇
  1975年   12篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Our objective was to test the hypothesis that internal medicine residents can be trained to screen for abdominal aortic aneurysm (AAA) using personal ultrasound imagers. We trained 5 randomly chosen internal medicine residents to image the abdominal aorta for patients with risk factors for AAAs using personal ultrasound imagers. Residents were trained in 3 or 4 one-on-one sessions with an instructor. To be eligible, patients had to be older than 65 years and have hypertension. After training, each of the 5 residents studied 3 patients independently. In 12 of the residents' 15 unsupervised studies, their abdominal aorta measurements were within 5 mm of the instructor's measurements with standard echocardiography (mean difference 3 mm, range 0-6 mm). Residents detected 3 previously unknown AAAs measuring 5.2, 4.2, and 3.9 cm in diameter. We conclude residents can be trained to image the abdominal aorta with personal ultrasound imagers and to identify AAAs in patients at risk.  相似文献   
62.
·病例简介:患者,男,22岁。因鼻部(见图1)、左侧肩部(见图2)、右侧背部及左侧大腿部皮疹就诊。既往身体健康,近期有到加利福尼亚中央谷旅游史,否认异地长期居住史,近期无服药史。患者无发热,无夜间盗汗,无寒战。既往诊断为耐甲氧西林金黄色葡萄球菌(MRSA)感染,接受甲氧苄氨嘧啶  相似文献   
63.
BACKGROUND: Metyrapone blocks cortisol synthesis which results in removal of negative feedback, a stimulation of hypothalamic corticotropin releasing factor (CRF) and a reduction in delta sleep. We previously reported a diminished delta sleep and hypothalamic-pituitary-adrenal (HPA) response to metyrapone in men with post-traumatic stress disorder (PTSD). In this study, we aimed to extend these findings to women. METHODS: Three nights of polysomnography were obtained in 17 women with PTSD and 16 controls. On day 3, metyrapone was administered throughout the day up until bedtime. Plasma adrenocorticotropic hormone (ACTH), cortisol, and 11-deoxycortisol were obtained the morning following sleep recordings the day before and after metyrapone administration. RESULTS: There were no significant between-group differences in hormone concentration and delta sleep at baseline. Relative to controls, women with PTSD had decreased ACTH and delta sleep responses to metyrapone. Decline in delta sleep was associated with the magnitude of increase in ACTH across groups. CONCLUSIONS: Similar to our previous findings in men, the ACTH and sleep electroencephalogram response to metyrapone is attenuated in women with PTSD. These results are consistent with a model of downregulation of CRF receptors in an environment of chronically increased CRF activity or with enhanced negative feedback regulation in PTSD.  相似文献   
64.
The clinical presentation of SARS is nonspecific and diagnostic tests do not provide accurate results early in the disease course. Initial diagnosis remains reliant on clinical assessment. To identify features of the clinical assessment that are useful in SARS diagnosis, the exposure status and the prevalence and timing of symptoms, signs, laboratory and radiographic findings were determined for all adult patients admitted with suspected SARS during the Toronto SARS outbreak. Findings were compared between patients with laboratory-confirmed SARS and those in whom SARS was excluded by laboratory or public health investigation. Of 364 cases, 273 (75%) had confirmed SARS, 30 (8%) were excluded, and 61 (17%) remained indeterminate. Among confirmed cases, exposure occurred in the healthcare environment (80%) or in the households of affected patients (17%); community or travel-related cases were rare (<3%). Fever occurred in 97% of patients by the time of admission. Respiratory findings including cough, dyspnea and pulmonary infiltrates evolved later and were present in only 59, 37 and 68% of patients, respectively, at admission. Direct exposure, fever on the first day of illness, and elevated temperature, pulmonary infiltrates, lymphopenia and thrombocytopenia at admission were associated with confirmed cases. Rhinorrhea, sore throat, and an elevated neutrophil count at admission were associated with excluded cases. In the absence of fever or significant exposure, SARS is unlikely. Other clinical, laboratory and radiographic findings further raise or lower the likelihood of SARS and provide a rational basis for estimating the likelihood of SARS and directing initial management.  相似文献   
65.
Botulinum Toxin A in the Treatment of Chromhidrosis   总被引:1,自引:0,他引:1  
Background. Chromhidrosis is an uncommon disorder characterized by secretion of colored sweat by apocrine glands, typically localized to the face or axilla. The current treatments available for chromhidrosis are time consuming and frequently ineffective.
Objective. Our purpose is to demonstrate a novel approach to the treatment of apocrine chromhidrosis.
Methods. We report a case of apocrine chromhidrosis successfully treated with botulinum toxin A (BTX-A; Botox).
Results. BTX-A therapy successfully controlled facial chromhidrosis, and the effects were visible at 19 weeks post-treatment. The therapeutic benefits may be attributed to its inhibitory effects on cholinergic stimulation, adrenergic stimulation, and substance P release, although further studies are necessary to elucidate the precise mechanism of action.
Conclusion. This report demonstrates a new therapeutic approach to patients suffering from chromhidrosis.  相似文献   
66.
67.
Clinical practice guidelines recommend antiviral prophylaxis to cytomegalovirus (CMV) donor-positive/recipient-negative (D+/R-) liver transplant recipients. We assessed the outcome of this strategy by determining the incidence, clinical features, and risk factors of CMV disease among CMV D+/R- liver transplant recipients who received antiviral prophylaxis. Sixty-seven CMV D+/R- liver transplant recipients (mean age+/-standard deviation: 49.5+/-11.4 years; 75% male) received oral ganciclovir [n=9 (13%)] or valganciclovir [n=58 (87%)] prophylaxis for a median duration of 92 days (interquartile range: 91-100). No breakthrough CMV disease was observed during antiviral prophylaxis. However, primary CMV disease was observed in 2%, 25%, 27%, 27%, and 29% of patients at 1, 3, 6, 12, and 24 months, respectively, after antiviral prophylaxis was stopped. The incidence of delayed-onset primary CMV disease was similar between those who received oral ganciclovir and valganciclovir. Nine (47%) patients had CMV syndrome, 8 (42%) had gastrointestinal CMV disease, and 2 (11%) had CMV hepatitis. Female patients (P=0.01) and younger age at transplant (P=0.03) were associated with an increased risk, whereas diabetes mellitus (P<0.001) was significantly associated with a lower risk of delayed-onset primary CMV disease. Allograft loss or mortality occurred in 8 (12%) patients during the median follow-up period of 3.31 (range: 0.8-5.9) years. No significant association was observed between CMV disease and patient and allograft survival. In conclusion, CMV disease remains a common complication in CMV D+/R- liver transplant patients during the contemporary era of antiviral prophylaxis. Female patients and younger patients are at increased risk of delayed-onset primary CMV disease.  相似文献   
68.
69.
70.
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