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   623篇
  免费   81篇
  国内免费   10篇
耳鼻咽喉   6篇
儿科学   13篇
妇产科学   12篇
基础医学   57篇
口腔科学   5篇
临床医学   84篇
内科学   161篇
皮肤病学   16篇
神经病学   34篇
特种医学   94篇
外科学   62篇
综合类   7篇
现状与发展   1篇
预防医学   49篇
眼科学   3篇
药学   45篇
中国医学   1篇
肿瘤学   64篇
  2023年   28篇
  2022年   6篇
  2021年   11篇
  2020年   23篇
  2019年   11篇
  2018年   21篇
  2017年   23篇
  2016年   22篇
  2015年   12篇
  2014年   28篇
  2013年   26篇
  2012年   22篇
  2011年   23篇
  2010年   25篇
  2009年   18篇
  2008年   19篇
  2007年   26篇
  2006年   16篇
  2005年   18篇
  2004年   17篇
  2003年   12篇
  2002年   16篇
  2001年   10篇
  2000年   18篇
  1999年   23篇
  1998年   22篇
  1997年   8篇
  1996年   9篇
  1995年   9篇
  1994年   20篇
  1993年   13篇
  1992年   14篇
  1991年   7篇
  1990年   5篇
  1989年   16篇
  1988年   12篇
  1987年   9篇
  1986年   8篇
  1985年   10篇
  1984年   13篇
  1983年   6篇
  1982年   9篇
  1981年   11篇
  1980年   8篇
  1979年   4篇
  1978年   3篇
  1977年   4篇
  1975年   6篇
  1974年   4篇
  1973年   5篇
排序方式: 共有714条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
Chronic graft-versus-host disease (cGVHD) is a major complication after stem cell transplantation (HSCT). Several randomized studies already demonstrated that anti-T lymphoglobulin (ATLG) is effective in preventing GVHD after myeloablative unrelated and HLA-identical sibling transplants. However, the issue of doses and the potential increase of relapses still remain unsolved. Here we report data on 190 patients with acute leukemia and myelodysplastic syndrome who underwent an unrelated HSCT with low-dose ATLG (15 to 30 mg/kg) given at an earlier timing (days –6 to –2). HSCT was performed from HLA 10/10 (n?=?62, 33%), 9/10 (n?=?91, 48%), 8/10 (n?=?30, 16%), and <8/10 (n?=?7, 4%) identical unrelated donor. Peripheral blood was the stem cell source in 42% (n?=?80). Median follow-up was 51 months. Grades II to IV and III to IV acute GVHD were 26% and 9%, respectively, and 2-year overall and moderate to severe cGVHD were 23% and 14%, respectively. The 3-year incidences of relapse and nonrelapse mortality were 26% and 18%, respectively. The rates of 3-year overall survival (OS), disease-free survival (DFS), and GVHD-free and relapse-free survival (GRFS) were 60%, 56% and 44%, respectively. Factors such as younger donor, good performance status, and early disease were associated with better outcome in terms of OS, DFS, and GRFS. Our data indicate that doses of ATLG lower that those used in randomized clinical trials can be used for GVHD prevention, even in the adult setting, without clear increases in relapse and infections; these findings need to be further validated by a prospective randomized study.  相似文献   
5.
Rotavirus A (RVA) is the leading cause of acute viral gastroenteritis in children under 5 years of age worldwide. G9P[8] is a common RVA genotype that has been persistently prevalent in Jiangsu, China. To determine the genetic diversity of G9P[8] RVAs, 7 representative G9P[8] strains collected from Suzhou Children’s Hospital between 2010 and 2016 (named JS2010‐JS2016) were analyzed through whole‐genome sequencing. All evaluated strains showed the Wa‐like constellation G9‐P[8]‐I1‐R1‐C1‐M1‐A1‐N1‐T1‐E1‐H1. Furthermore, phylogenetic analysis revealed that the VP7 genes of all strains clustered into lineage G9‐III and G9‐VI. With the exception of strain JS2012 (P[8]‐4), the VP4 sequences of all strains belonged to the P[8]‐3 lineage. Sequencing further revealed that amino acid substitutions were present in the antigenic regions of the VP7 and VP4 genes of all strains. Moreover, there were multiple substitutions in antigenic sites I and II of the nonstructural protein 4 (NSP4) genes, whereas the other NSP genes were relatively conserved. In conclusion, our phylogenetic analysis of these 7 G9P[8] strains suggests that RVA varied across regions and time. Therefore, our findings suggest that continued surveillance is necessary to explore the molecular evolutionary characteristics of RVA for better prevention and treatment of acute viral gastroenteritis.  相似文献   
6.
7.
目的:实验于2006-02/07在锦州医学院科学实验中心完成。将72只健康SD大鼠按随机数字表法分为假手术组、模型组、神经生长因子治疗组,每组24只。采用Logna等改良法复制大脑中动脉血栓模型,动物清醒2h后进行功能评价,动物神经功能达到2级的纳入实验。假手术组除不进行大脑中动脉线栓外,其余同模型组。神经生长因子治疗组于缺血后立即腹腔注射神经生长因子1000μg/kg,1次/d。于缺血后1,3,7,14d处死动物,运用免疫组化和免疫荧光双标的方法观察神经生长因子对脑缺血后神经干细胞巢蛋白的表达及其细胞类型的影响。结果:72只大鼠均进入结果分析。①神经生长因子治疗组和模型组大脑皮质均可见巢蛋白阳性细胞,细胞呈圆形或椭圆形。与模型组相比,除缺血后1d外,神经生长因子治疗组其他时间点的巢蛋白阳性细胞数均明显高于模型组,两组缺血后各时间点的巢蛋白阳性细胞数均高于假手术组[模型组:(3.47±0.51),(5.13±1.14),(13.95±3.56),(8.97±2.08)个;神经生长因子治疗组:(3.81±0.66),(9.88±2.08),(19.87±3.86),(26.17±2.90)个,假手术组:0,P<0.05,P<0.01]。②模型组和神经生长因子治疗组3d时缺血皮质巢蛋白阳性突起主要与胶质纤维酸性蛋白共存,14d时巢蛋白与神经元特异性烯醇化酶共存明显增多。结论:神经生长因子能增加局灶性脑缺血后巢蛋白的阳性细胞的数目,并促进其分化为神经元和神经胶质细胞。  相似文献   
8.
9.
The reduction of neutrophil migration to an infectious focus is associated with a high mortality in severe sepsis. Previously, we showed that heme oxygenase (HO) products downregulate neutrophil recruitment in a noninfectious inflammatory model. The present study was designed to determine the role of HO in sepsis induced by cecal ligation and puncture (CLP) model. We demonstrated that pretreatment, but not the combination of pretreatment plus posttreatment with zinc protoporphyrin IX (ZnPP IX), an HO inhibitor, prevented the reduction of CXCR2 on circulating neutrophils and the failure of intraperitoneal neutrophil migration to the site of infection. Consequently, bacterial dissemination, systemic inflammatory response, and organ injury were prevented. In addition, pretreatment with the HO inhibitor avoided hypotension and consequently increased survival. Moreover, in mice subjected to severe CLP, the pretreatment, but not the combination of pretreatment plus posttreatment with ZnPP IX, prevented the increase of plasmatic free heme observed in nontreated severe CLP. The administration of exogenous hemin to mice subjected to moderate sepsis consistently increased the mortality rate. Furthermore, hemin resulted in a reduction of neutrophil migration both in vivo and in vitro. Altogether, our results demonstrated that pretreatment with the HO inhibitor prevents the pathological findings in severe CLP. However, the combination of pretreatment plus posttreatment with ZnPP IX enhances sepsis severity because of an increase in circulating levels of heme, which is deleterious to the host tissues and also inhibits neutrophil migration.  相似文献   
10.
Background: The daily consumption of dietary fiber is frequently below suggested recommendations. Using a double‐blind, controlled, randomized study, we assessed the efficiency and tolerance of a fiber‐enriched orange juice to supplement fiber intake in women. Materials and Methods: After 1 week of noninterventional observation, 192 healthy adult women ingested 400 mL of orange juice for 21 days, which either was not (placebo group) or was enriched with fiber (fiber group). Orange juice ingestion was registered daily and controlled for each week during the study period. Macronutrient, fiber, and energy intake were determined using a 3‐day food record, validated food chemical composition databases, and the “Pro Diet” software. Gastrointestinal symptoms were self‐evaluated daily by scoring 4 grades of symptom intensity and using a visual analog scale to grade pain severity. Results: No changes were observed for macronutrient and energy ingestion. For the placebo group (n = 97), the total fiber intake record was under the daily recommended value. In contrast, the fiber group (n = 95) displayed higher comparative values of total and soluble fiber consumption (P ≤ .001), achieving the daily recommended values of fiber intake. Both groups reported an increased frequency of slight bloating and rumbles over time (P ≤ .05). The fiber group also experienced a higher frequency of slight flatulence over time (P = .002). Conclusion: Consumption of fiber‐enriched orange juice was efficient to achieve the daily fiber intake recommendation for women, was not accompanied by intense adverse events, and may represent a suitable method to supplement fiber intake in woman.  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