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   6790篇
  免费   395篇
  国内免费   52篇
耳鼻咽喉   120篇
儿科学   170篇
妇产科学   113篇
基础医学   928篇
口腔科学   830篇
临床医学   488篇
内科学   1374篇
皮肤病学   159篇
神经病学   394篇
特种医学   245篇
外科学   724篇
综合类   21篇
一般理论   3篇
预防医学   807篇
眼科学   93篇
药学   471篇
  1篇
中国医学   76篇
肿瘤学   220篇
  2024年   12篇
  2023年   65篇
  2022年   164篇
  2021年   300篇
  2020年   193篇
  2019年   240篇
  2018年   309篇
  2017年   206篇
  2016年   245篇
  2015年   246篇
  2014年   344篇
  2013年   354篇
  2012年   547篇
  2011年   639篇
  2010年   372篇
  2009年   248篇
  2008年   412篇
  2007年   362篇
  2006年   295篇
  2005年   262篇
  2004年   197篇
  2003年   186篇
  2002年   167篇
  2001年   99篇
  2000年   93篇
  1999年   67篇
  1998年   47篇
  1997年   37篇
  1996年   49篇
  1995年   44篇
  1994年   42篇
  1993年   29篇
  1992年   29篇
  1991年   33篇
  1990年   19篇
  1989年   36篇
  1988年   35篇
  1987年   30篇
  1986年   26篇
  1985年   23篇
  1984年   19篇
  1983年   12篇
  1982年   15篇
  1981年   11篇
  1980年   10篇
  1979年   7篇
  1978年   6篇
  1977年   12篇
  1976年   6篇
  1969年   7篇
排序方式: 共有7237条查询结果,搜索用时 15 毫秒
61.
OBJECT: The purpose of this metaanalysis was to investigate possible gender differences in traumatic brain injury (TBI) sequelae. The case fatality rates in patients after TBI have previously been shown to be significantly higher in women as compared with men. METHODS: A quantitative review of published studies of TBI outcome revealed eight studies (20 outcome variables) of TBI, in which outcome was reported separately for men and women. CONCLUSIONS: Outcome was worse in women than in men for 85% of the measured variables, with an average effect size of -0.15. Although clinical opinion is often that women tend to experience better outcomes than men after TBI, the opposite pattern was suggested in the results of this metaanalysis. However, this conclusion is limited by the fact that, in only a small percentage of the total published reports on TBI outcome, was outcome described separately for each sex. A careful, prospective study of sex differences in TBI outcome is clearly needed.  相似文献   
62.
Different peptides have been isolated from a wide range of animal species. It is has become increasingly clear that due to the development of antibiotic-resistant microbes, antibacterial and antifungal peptides have attracted the attention in recent years, in order to find new therapeutic agents. In this work, a novel peptide with high inhibitory activity against fungi growth have been isolated from the venom of the Brazilian snake Bothrops jararaca. A Sephacryl S-100 gel filtration column was employed for further separation of proteins. The FV fraction with high antifungal activity was named Pep5Bj, pooled and submitted to reverse-phase chromatography in HPLC. The fraction containing the isolated peptide inhibited the growth of different phytopathogenic fungi (Fusarium oxysporum and Colletotrichum lindemuthianum) and yeast (Candida albicans and Saccharomyces cerevisiae). The peptide minimal inhibitory concentration is comparable to other known antifungal peptides, like insect defensins and cecropins, found in the last years in a large diversity of animals. We investigate F. oxysporum cells membrane permeabilization using SYTOX Green uptake, an organic compound that fluoresces upon interaction with nucleic acids after penetration in cell with compromised plasma membranes. When viewed under fluorescence optical microscopy, F. oxysporum cells exposed to Pep5Bj display strong SYTOX Green fluorescence in the cytosol, especially in the nuclei. The SYTOX Green data suggested that this effect is related to membrane permeabilization. The molecular masses of this peptide was obtained by MALDI-TOF spectrometry and corresponded to 1370Da.  相似文献   
63.
64.
Objective Poor compliance to antihypertensive medications has been identified as a primary cause of uncontrolled blood pressure (BP), with consequent increases in hypertension‐related morbidity and mortality. Therefore, any measure known to improve compliance should be encouraged. This study assessed the impact of reminder cards on compliance to antihypertensive therapy. Method A field trial was undertaken in pharmacies located in the districts of Lisbon and Porto. Eligible participants comprised those aged 30–74 years, prescribed an angiotensin‐converting enzyme inhibitor (ACEI) in monotherapy, and taken on a once‐daily regimen. Patients were allocated to control group (CG) or intervention group (IG), the latter being provided with a reminder card, an alarm‐type device due to remind the patient of the time to take his medication. Patients were monitored monthly during 3 months for compliance and blood pressure control. Key findings Seventy‐one patients participated in the study (intervention: 35; control group: 36). Compliance was similar between the groups in the first 2 months of follow‐up (97.1% IG vs 94.9% CG at first follow‐up and 97.5% IG vs 94.2% CG at second follow‐up) and higher in the intervention group at the end of the study (97.3% IG vs 87.3% CG; P = 0.011). There were no mean blood pressure differences between compliant and non‐compliant subjects at the end of the study (P value for differences in systolic BP (Psyst) = 0.580; and P value for differences in diastolic BP (Pdlast) = 0.175). Conclusion This small‐scale study indicates a possible positive impact on patients' compliance resulting from the use of reminder cards. However, this needs confirming in larger scale studies with longer monitoring periods.  相似文献   
65.
In the present study, we evaluated the effect of fructose-1,6-bisphosphate (FBP), a high energy intermediate metabolite of glycolysis, in an acute model of lung injury. Injection of carrageenan into the pleural cavity of rats elicited an acute inflammation response characterized by a fluid accumulation in the pleural cavity which contained a large number of polymorphonuclear neutrophils. FBP (500mg/kg) attenuated the inflammation parameters: exudate volume, total leukocytes and the number of polymorphonuclear leukocytes, but the protein concentration in the exudate was not significantly affected by treatment with FBP. The precise site and mechanism of the anti-inflammatory effect was not addressed, considering the diverse pharmacological actions of FBP. This drug has anti-inflammatory actions suggesting that it may represent a novel strategy for the modulation of inflammatory response.  相似文献   
66.
67.
68.
In the Nonobese diabetic (NOD) mouse, a spontaneous model of type 1 diabetes, the pathogenic process is classically thought to start at 3-4 weeks of age with an accumulation of antigen-presenting cells (APC), especially CD11c+ dendritic cells (DC), around the pancreatic islets of Langerhans. Concomitantly, hyperinsulinemia and slight hyperglucagonemia are observed, which may be either the cause or consequence of the initial APC infiltration. To determine whether infiltrating DC can affect islet activity in control (C57BL/6) and NOD mice, we performed experiments in which islets and DC were isolated and co-cultured. We first showed that, immediately after isolation, islets from 8-week-old prediabetic NOD mice had significantly higher insulin and glucagon contents than those from C57BL/6 controls. Moreover, as is the case in vivo, prediabetic NOD mouse islets secrete more insulin in vitro at 11.1 mM glucose than C57BL/6 ones. In DC-islet co-cultures, insulin secretion was significantly increased for NOD mice only, while that of glucagon was not significantly affected. These findings indicate that NOD DC are good candidates for stimulating the NOD mouse &#103 -cell hyperactivity that is observed both in vivo and in vitro, and might, consequently, sensitize NOD islets to an autoimmune attack.  相似文献   
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