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   6145篇
  免费   343篇
  国内免费   67篇
耳鼻咽喉   69篇
儿科学   394篇
妇产科学   87篇
基础医学   814篇
口腔科学   134篇
临床医学   482篇
内科学   1144篇
皮肤病学   130篇
神经病学   313篇
特种医学   269篇
外科学   838篇
综合类   312篇
一般理论   3篇
预防医学   350篇
眼科学   129篇
药学   611篇
  2篇
中国医学   41篇
肿瘤学   433篇
  2023年   38篇
  2022年   79篇
  2021年   188篇
  2020年   100篇
  2019年   130篇
  2018年   160篇
  2017年   121篇
  2016年   138篇
  2015年   166篇
  2014年   221篇
  2013年   288篇
  2012年   371篇
  2011年   348篇
  2010年   240篇
  2009年   206篇
  2008年   309篇
  2007年   272篇
  2006年   295篇
  2005年   250篇
  2004年   207篇
  2003年   193篇
  2002年   189篇
  2001年   144篇
  2000年   156篇
  1999年   133篇
  1998年   101篇
  1997年   77篇
  1996年   67篇
  1995年   48篇
  1994年   46篇
  1993年   41篇
  1992年   100篇
  1991年   85篇
  1990年   77篇
  1989年   96篇
  1988年   86篇
  1987年   73篇
  1986年   81篇
  1985年   74篇
  1984年   47篇
  1983年   28篇
  1982年   40篇
  1981年   27篇
  1980年   32篇
  1979年   41篇
  1977年   40篇
  1976年   26篇
  1975年   40篇
  1974年   30篇
  1972年   32篇
排序方式: 共有6555条查询结果,搜索用时 15 毫秒
101.
Transdiaphragmatic extension of hydatid cyst (HC) or cystic echinococcosis (CE) of the liver is a rare phenomenon. We report a case that presented as a right middle lobe consolidation. The diagnosis of transdiaphragmatic extension of hepatic hydatid cyst was suspected on CT scan of the chest and abdomen, and confirmed operatively. A successful outcome was achieved by a combination of pre- and post-operative albendazole therapy combined with surgery.  相似文献   
102.
103.
An unusual case of colitis   总被引:1,自引:0,他引:1  
  相似文献   
104.
ABSTRACT— We studied the risk of post-transfusion hepatitis (PTH) in recipients of blood collected from voluntary donors screened for HBsAg. Two hundred and fifty patients without any previous history of liver disease or transfusion were followed up for 12 months subsequent to cardiac surgery. Thirty-five of them had closed-heart surgery without receiving transfusion and served as controls. The remaining 215 patients received single-point transfusions (mean 4 ± 2.4 units). None of the controls and 15 (6.9%) blood recipients developed PTH. Three (20%) patients had hepatitis-B-virus-induced hepatitis while the remainder (80%) had non A, non B (NANB) hepatitis. The number of units of blood transfused and surrogate markers for development of PTH (donor alanine aminotransferase, anti-HBc and anti-HBs antibody) were not associated with the occurrence of PTH (p>0.05). Nine (60%) of the 15 patients developing PTH were asymptomatic. All the patients recovered from the PTH, except one who died of fulminant hepatitis. At the end of 1 year of follow-up, none of the patients had evidence of chronic hepatitis. Only three (25%) of the patients with NANB-PTH developed anti-hepatitis C virus (HCV) antibody during the follow-up. We conclude that the incidence of PTH in India is similar to other parts of the world and NANB virus was the major cause of the PTH. The absence of chronicity and lack of seroconversion to anti-HCV antibody in the majority of the patients after 1 year of follow-up may suggest the possibility of a NANB virus other than HCV as the major cause of PTH in India.  相似文献   
105.
Vecchini  F; Patrene  KD; Boggs  SS 《Blood》1993,81(6):1489-1496
Mouse bone marrow (BM) was separated into low-density, lineage- negative, wheat germ agglutinin-positive (WGA+), Rhodamine-123 bright (Rhbright) or dim (Rhdim) cells to obtain populations that were highly enriched for committed progenitors (Rhbright cells) or for more primitive stem cells (Rhdim). When 2,500 Rhbright or Rhdim cells were seeded onto 6-week-old irradiated (20 Gy) long-term BM cultures (LTBMC), the nonadherent cell production from Rhbright cells was transient and ended after 5 weeks. Production from Rhdim cells did not begin until week 3, peaked at week 5, and ended at week 8, when the irradiated stroma seemed to fail. Termination of cell production from Rhdim cells did not occur in nonirradiated LTBMC from W41/Wv mice. During peak nonadherent cell production, 25% to 30% of the cells in the nonirradiated LTBMC from W41/Wv mice had donor cell markers. Two approaches were tested to try to enhance the proportion or number of donor cells. Addition of Origen-HGF at the time of seeding Rhdim cells caused a nonspecific increase in both host and donor cell production, but a specific increase in production of donor cells was obtained by seeding the cultures at 2 weeks rather than 6 weeks. Limiting dilution of Rhdim cells gave the same frequency of wells producing cells on both irradiated +/+ and nonirradiated W41/Wv or W/Wv cultures.  相似文献   
106.
BackgroundThe American Heart Association (AHA) has defined Life's Simple 7 (LS7) as a measure of overall cardiovascular health . Nonalcoholic fatty liver disease (NAFLD) has been involved as a risk factor for cardiovascular disease. We evaluated the association between LS7 and NAFLD.MethodsWe evaluated participants form the Multi-Ethnic Study of Atherosclerosis (MESA) cohort. Cardiovascular health score was calculated from the Life's Simple 7 metrics. A score of 0-8 was considered inadequate, 9-10 average, and 11-14 optimal. NAFLD was defined using noncontrast cardiac computed tomography (CT) and a liver/spleen attenuation ratio (L/S) < 1. Multivariable regression were performed to evaluate the association.ResultsOur cross-sectional analysis of 3901 participants showed 19% (n = 747) had optimal cardiovascular health, 33% (n = 1270) had average, and 48% (n = 1884) had inadequate. White participants were most likely to have an optimal score (51%, n = 378), whereas African American participants had the lowest proportion with optimal scores (16%, n = 120; P < 0.001). The overall prevalence of NAFLD was 18% with a distribution of 7%, 14%, and 25% in the optimal, average, and inadequate score categories, respectively (P < 0.001). Adjusted for risk factors, average and optimal health categories had lower odds of NAFLD compared to those with inadequate scores: odds ratio for average, 0.44 (95% confidence interval 0.36-0.54); optimal, odds ratio 0.19 (95% confidence interval 0.14-0.26). This association was similar across gender, race and age groups.ConclusionA more favorable cardiovascular health score was associated with a lower prevalence of NAFLD. This study may suggest a potential of Life's Simple 7 in the prevention of liver disease.  相似文献   
107.
Past few decades have witnessed the dawn of new diseases in which cancer is a major problem and the race ensued to eradicate cancer by charting out various effective therapeutic regimens. Circumventing resistance issues and combating the toxicity and selectivity problems are matter-of-concern in cancer treatment. Persistent failure to ensure complete remission and eradication of cancer instigated the researchers to exploit the strategies of combining pharmacophores as targeted therapeutic agents. Momentous improvement in the pharmacokinetic as well as pharmacodynamic profile resulting in the enhancement of bioavailability was seen with the introduction of these pharmacophores. The scope of molecular hybridization can be clearly exemplified through the US-FDA approved estramustine and others such as CUDC-101, CBLC-137, PLX3397, E-3810, and CUDC-907 that are currently in different phases of clinical trials. This review seeks to highlight and discuss anti-proliferative activity of some important hybrid, dual, and multi-targeted pharmacophores reported to date along with their designs, structure activity relationships, scope, and limitations. Further, an emphasis has been made to summarize US-FDA approved as well as drugs currently undergoing clinical trials of anticancer drug development.  相似文献   
108.
IntroductionThe variable course of illness in patients of Tubercular lymphadenitis remains a therapeutic challenge to treating physicians in a significant proportion of patients. This study was aimed to explore the possible determinants which could predict the outcome of this subgroup of patients.MethodologyThis was a prospective cohort study where 94 patients of TB lymphadenitis were enrolled who could be followed up till the end of treatment. They were evaluated in the beginning and monitored till the end of treatment keeping into account the clinical behaviour of lymph nodes during the course of Anti tubercular chemotherapy.ResultsOut of 94 patients, 60 had their lymph nodes resolved at the end of prescribed treatment duration wheras 34 were classified as partial responders. Another 26 amongst them had their nodes resolved by an extension of continuation phase by 3–6 months. Presence of bilateral and multiple lymph nodes, necrosis on Fine needle aspiration at initial diagnosis and occurrence of Paradoxical upgrading reaction were associated with the partial resolution of lymph nodes at the end of stipulated ATT duration.ConclusionTreatment duration should be individualized by the treating physicians. Certain parameters mentioned above can be taken as warning signals of patients ending up as partial responders and hence the need of a prolonged extension phase.  相似文献   
109.
110.
Digestive Diseases and Sciences - While there is recent literature to support the discontinuation of 5-aminosalicylate (5-ASA) upon the initiation of biologics, continuing 5-ASA after treatment...  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