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   6393篇
  免费   390篇
  国内免费   45篇
耳鼻咽喉   119篇
儿科学   134篇
妇产科学   104篇
基础医学   899篇
口腔科学   823篇
临床医学   451篇
内科学   1242篇
皮肤病学   151篇
神经病学   392篇
特种医学   143篇
外科学   716篇
综合类   14篇
一般理论   3篇
预防医学   798篇
眼科学   94篇
药学   462篇
中国医学   70篇
肿瘤学   213篇
  2024年   12篇
  2023年   65篇
  2022年   161篇
  2021年   299篇
  2020年   193篇
  2019年   239篇
  2018年   306篇
  2017年   205篇
  2016年   243篇
  2015年   244篇
  2014年   335篇
  2013年   343篇
  2012年   541篇
  2011年   635篇
  2010年   352篇
  2009年   232篇
  2008年   403篇
  2007年   349篇
  2006年   287篇
  2005年   260篇
  2004年   195篇
  2003年   179篇
  2002年   165篇
  2001年   87篇
  2000年   87篇
  1999年   63篇
  1998年   31篇
  1997年   24篇
  1996年   18篇
  1995年   11篇
  1994年   9篇
  1993年   12篇
  1992年   32篇
  1991年   24篇
  1990年   15篇
  1989年   20篇
  1988年   15篇
  1987年   18篇
  1986年   16篇
  1985年   17篇
  1984年   11篇
  1983年   9篇
  1982年   9篇
  1981年   7篇
  1979年   5篇
  1977年   6篇
  1976年   4篇
  1970年   4篇
  1969年   7篇
  1968年   3篇
排序方式: 共有6828条查询结果,搜索用时 15 毫秒
91.
The objective of this study was to investigate the effect of meloxicam-loaded nanocapsules (M-NC) on the treatment of the memory impairment induced by amyloid β-peptide (aβ) in mice. The involvement of Na+, K+-ATPase and cyclooxygenase-2 (COX-2) activities in the hippocampus and cerebral cortex was also evaluated. Mice received aβ (3 nmol/ 3 μl/ per site, intracerebroventricular) or vehicle (3 μl/ per site, i.c.v.). The next day, the animals were treated with blank nanocapsules (17 mL/kg) or M-NC (5 mg/kg) or free meloxicam (M-F) (5 mg/kg). Treatments were performed every other day, until the twelfth day. Animals were submitted to the behavioral tasks (open-field, object recognition, Y-maze and step-down inhibitory avoidance tasks) from the twelfth day. Na+, K+-ATPase and COX-2 activities were performed in hippocampus and cerebral cortex. aβ caused a memory deficit, an inhibition of the hippocampal Na+, K+-ATPase activity and an increase in the hippocampal COX-2 activity. M-NC were effective against all behavioral and biochemical alterations, while M-F restored only the COX-2 activity. In conclusion, M-NC were able to reverse the memory impairment induced by aβ, and Na+, K+-ATPase is involved in the effect of M-NC.  相似文献   
92.
93.
Odontology - This study aimed at evaluating the influence of glass-fiber post (GFP) relining with composites of different opacities on resin cement layer thickness (CLT), bond strength (BS) to root...  相似文献   
94.
Lifelong learning (LLL) is an essential feature for the doctor to keep clinically updated and has been described as an indicator of competence and professionalism. The aim of this study was to evaluate the association between career satisfaction in psychiatry, lifelong learning, and commitment in scientific activities, taking into account other personal and professional effects. The survey was sent to 453 national psychiatrists and 190 surveys (41.9%) were completed online and validated. The Jefferson Scale of Physician Lifelong Learning (JSPLL) was used to assess the level of LLL for each doctor. The results of the analysis of JSPLL showed that participants more satisfied with their career have greater motivation and invest more in the LLL. Furthermore, participants who were more satisfied with their career had a higher percentage of scientific activity in the last year. Multiple linear regression with these two effects in the model revealed a positive association between career satisfaction in psychiatry, LLL and the publication of scientific papers, leading to the main conclusion that satisfaction with a career in psychiatry has a significant correlation with LLL and with involvement in scientific activities.  相似文献   
95.
96.
Through the Life Cycle of Intraoperative Transesophageal Echocardiography (ETTI/SBA) the Brazilian Society of Anesthesiology, together with the Department of Cardiovascular Image of the Brazilian Society of Cardiology (DIC/SBC), createded a task force to standardize the use of intraoperative transesophageal echocardiography by Brazilian anesthesiologists and echocardiographers based on scientific evidence from the Society of Cardiovascular Anesthesiologists/American Society of Echocardiography (SCA/ASE) and the Brazilian Society of Cardiology.  相似文献   
97.
98.
Obesity and absence of physical exercise are global problems that affect concentration and sperm quality in the male reproductive system. The purpose of this study was to examine the effect of obesity and resistance training, considered separately or in association, on testicular function and reproductive capacity. Twenty pubertal male Wistar rats were distributed into four groups: control (C) and exercise (E) groups that received standard rat chow; and obese (O) and obese with exercise (OE) groups that received a high‐fat diet. All the groups received filtered water during the experimental conditions. Groups E and OE were submitted to 8 weeks of high‐intensity intermittent training. Afterwards, testes were collected for sperm count, spermatogenic kinetics, histopathology, morphometry and immunodetection of androgen receptors (AR). The vas deferens was collected for sperm morphology. The results showed that obesity increased body weight, naso‐anal length, liver and epididymal fat weight, abnormal spermatozoa and immunodetectable AR. Intermittent exercise decreased daily sperm production (DSP), sperm count and normal spermatozoa, whereas the number of tubules with immunodetectable AR increased. The combination of obesity and intermittent training led to reduced sperm count and DSP, although abnormal spermatozoa and the number of tubules with immunodetectable AR increased. Thus, in conclusion, both obesity and resistance training impaired testicular function during puberty in rats; and this type of exercise has also been shown to be detrimental to testicular physiology.  相似文献   
99.
Dengue is currently a major public-health problem. Dengue virus (DENV) is classified into four distinct serotypes, DENV 1-4. After 28 years of absence, DENV-4 was again detected in Brazil in 2010 in Roraima State, and one year later, the virus was identified in the northern Brazilian states of Amazonas and Pará, followed by Rio de Janeiro and São Paulo. In Minas Gerais, the first confirmed case of DENV-4 occurred in the municipality of Frutal in 2011 and has now been isolated from a growing number of patients. Although DENV-2 is associated with the highest risk of severe forms of the disease and death due to the infection, DENV-4 has also been associated with severe forms of the disease and an increasing risk of hemorrhagic manifestations. Herein, the first fatal case of confirmed DENV-4 in Brazil is reported. The patient was an 11-year-old girl from the municipality of Montes Claros in northern Minas Gerais State, Brazil. She had idiopathic thrombocytopenic purpura as a comorbid condition and presented with a fulminant course of infection, leading to death due to hemorrhagic complications. Diagnosis was confirmed by detection of Dengue-specific antibodies using IgM capture enzyme-linked immunosorbent assay and semi-nested RT-PCR. Primary care physicians and other health-care providers should bear in mind that DENV-4 can also result in severe forms of the disease and lead to hemorrhagic complications and death, mainly when dengue infection is associated with coexisting conditions.  相似文献   
100.
Parasitology Research - The taeniasis/cysticercosis complex is a zoonosis caused by the presence of the parasite Taenia solium in humans. It is considered a neglected disease that causes serious...  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