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   9022篇
  免费   596篇
  国内免费   54篇
耳鼻咽喉   89篇
儿科学   266篇
妇产科学   318篇
基础医学   1245篇
口腔科学   134篇
临床医学   811篇
内科学   2026篇
皮肤病学   142篇
神经病学   830篇
特种医学   314篇
外科学   1303篇
综合类   61篇
一般理论   5篇
预防医学   471篇
眼科学   193篇
药学   689篇
中国医学   19篇
肿瘤学   756篇
  2023年   54篇
  2022年   178篇
  2021年   318篇
  2020年   136篇
  2019年   188篇
  2018年   245篇
  2017年   210篇
  2016年   212篇
  2015年   223篇
  2014年   288篇
  2013年   435篇
  2012年   628篇
  2011年   610篇
  2010年   367篇
  2009年   313篇
  2008年   518篇
  2007年   503篇
  2006年   513篇
  2005年   489篇
  2004年   455篇
  2003年   406篇
  2002年   368篇
  2001年   192篇
  2000年   156篇
  1999年   155篇
  1998年   85篇
  1997年   64篇
  1996年   71篇
  1995年   58篇
  1994年   66篇
  1993年   69篇
  1992年   119篇
  1991年   91篇
  1990年   69篇
  1989年   66篇
  1988年   64篇
  1987年   59篇
  1986年   35篇
  1985年   40篇
  1984年   45篇
  1983年   20篇
  1982年   25篇
  1981年   22篇
  1980年   22篇
  1979年   27篇
  1978年   22篇
  1974年   18篇
  1971年   24篇
  1969年   23篇
  1967年   18篇
排序方式: 共有9672条查询结果,搜索用时 15 毫秒
1.
2.
3.
This paper is an attempt to assess the relevance of the inhibitors of fibrinolysis for clot lysis in selected disease states and to discuss the mechanisms leading to acquired abnormal levels of such inhibitors. When compared to 20 control subjects the 30 hypertriglyceridemic patients (14 with type IIb and 16 with type IV) displayed significantly (p less than 0.001) increased plasma plasminogen activator inhibitor (PAI) activity (221 +/- 88% and 290 +/- 104% respectively; mean +/- SD), moderately (p less than 0.01) increased alpha 2 antiplasmin (alpha 2AP) level (112 +/- 11% and 115 +/- 16%) and accordingly an obviously prolonged dilute blood clot lysis time (DBCLT). Neither PAI activity and alpha 2AP level nor DBCLT were significantly different from controls in the 10 patients with hyperlipoproteinemia type IIa. The 18 patients with severe hepatic cirrhosis had low alpha 2AP level (59 +/- 19.7%) and accelerated clot lysis, while mean PAI activity (160 +/- 87%) was slightly (p less than 0.05) increased. In the 17 nephrotic patients alpha 2AP was increased (115 +/- 12%) while PAI activity was similar to controls and DBCLT rather shorter. Two liver secretion enzymes, namely serum cholinesterase and plasma protein C, were found to be decreased in cirrhotic patients, similar to control values in hyperlipoproteinemia type IIa and obviously increased in nephrotic patients as well as in hypertriglyceridemic subjects. The relevance of PAI and alpha 2AP for clot lysis was considered in relation to data in the literature concerning the behaviour of t-PA and factor XIII.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
The pediatric intensive care unit at a community hospital successfully implemented the use of standardized concentrations. The process included deciding the standardized concentrations, use of titration charts, and integration of smart pump technology. Since the implementation of standardized concentrations, there has been no signal or sentinel events reported. It is safe and efficacious to use standardized concentrations combined with smart pump technology and abandon the use of the rule of 6 in the pediatric population.  相似文献   
5.
6.
Flavocoxid (Limbrel), a proprietary mixture of flavonoid molecules (baicalin and catechin), was tested against a traditional nonsteroidal anti-inflammatory drug, naproxen, for the management of the signs and symptoms of moderate osteoarthritis (OA) in humans. Discomfort and global disease activity were used as the primary end points, and safety assessments were also taken for both treatments as a secondary endpoint. In this double-blind study, 103 subjects were randomly assigned to receive either flavocoxid [500 mg twice daily (BID)] or naproxen (500 mg BID) in a 1-month onset of action trial. Outcome measures included the short Western Ontario and McMaster University Osteoarthritis Index, subject Visual Analogue Scale for discomfort and global response, and investigator Visual Analogue Scale for global response and fecal occult blood. Both flavocoxid and naproxen showed significant reduction in the signs and symptoms of knee OA (P ≤ .001). There were no statistically detectable differences between the flavocoxid and naproxen groups with respect to any of the outcome variables. Similarly, there were no statistically detectable differences between the groups with respect to any adverse event, although there was a trend toward a higher incidence of edema and nonspecific musculoskeletal discomfort in the naproxen group. In this short-term pilot study, flavocoxid was as effective as naproxen in controlling the signs and symptoms of OA of the knee and would present a safe and effective option for those individuals on traditional nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors. A low incidence of adverse events was reported for both groups.  相似文献   
7.
The exposure of homeothermic animals to a cold environment leads to a powerful activation of orexigenic signalling which is accompanied by molecular and functional resistance to insulin-induced inhibition of feeding. Recent evidence suggests that AMPK participates in nutrient-dependent control of satiety and adiposity. The objective of the present study was to evaluate the effect of cold exposure upon the molecular activation of AMPK signalling in the hypothalamus of rats. Immunoblotting demonstrated that cold exposure per se is sufficient for inducing, on a time-dependent basis, the molecular activation of the serine/threonine kinase AMP-activated protein kinase (AMPK) and inactivation of the acetyl-CoA carboxylase (ACC). These molecular phenomena were accompanied by resistance to nutrient-induced inactivation of AMPK and activation of ACC. Moreover, cold-exposure led to a partial inhibition of a feeding-induced anorexigenic response, which was paralleled by resistance to insulin-induced suppression of feeding. Finally, cold exposure significantly impaired insulin-induced inhibition of AMPK through a mechanism dependent on the molecular cross-talk between phosphatidylinositol-3(PI3)-kinase/Akt and AMPK. In conclusion, increased feeding during cold exposure results, at least in part, from resistance to insulin- and nutrient-dependent anorexigenic signalling in the hypothalamus.  相似文献   
8.
We report a case of recurrent inguinal lymphocele formation after inguinal lymphadenectomy treated by lymphographic mapping and selective ligation of the lymphatic vessels. Lymphographic mapping was performed by puncturing a lymphatic vessel at the dorsum of the foot. After isolating the vessels that drained into the lymphocele, they were clipped and divided through a small skin incision. The described technique showed an instant and complete suspension of the lymph secretion with subsequent complete healing. Lymphatic mapping and selective ligation of afferent lymphatic vessels proved to be an effective treatment of a recurrent inguinal lymphocele.  相似文献   
9.
10.
The present study investigated the expression of c-erbB-2 in 59 meningiomas, including different histological subtypes and anaplastic variants, by immunocytochemistry and molecular biological techniques. Immunohistochemistry using the monoclonal antibody FWP-51 directed against c-erbB-2-encoded oncoprotein gp185 demonstrated variable degrees of immunoreactivity in all meningiomas. The intensity of immunostaining correlated with the degree of expression as assessed by Western analysis in 28 meningiomas using polyclonal antiserum 21N. There was no correlation between the degree of expression and histological variants. Immunoreactivity of all menigiomas was distinctly less intense, however, than that of the human breast cancer cell line SK-BR-3, and slightly lower than that of brain metastases of breast and ovarian carcinomas that served as positive controls for both methods. By Southern analysis all meningiomas showed a single copy of the c-erbB-2 gene. Non-neoplastic arachnoid cap cells also exhibited c-erbB-2 expression and the degree of immunoreactivity was comparable with the majority of meningiomas. These data argue against an overexpression of c-erbB-2 in meningiomas, but rather indicate a cell-type-specific constitutive expression of the c-erbB-2 gene product in meningiomas and their putative progenitor cells. Since a subgroup of meningiomas is known to express progesterone receptors (PR), gp185 immunoreactivity was compared to the hormone receptor status using monoclonal antibody KD68. Fifty-six percent meningiomas showed PR immunoreactivity, but there was no statistically significant correlation with the degree of gp185 expression.This study was supported by a grant of the Tumorzentrum Heidelberg/Mannheim (M.K., No. 10028060)  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