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   1978篇
  免费   131篇
  国内免费   13篇
耳鼻咽喉   21篇
儿科学   58篇
妇产科学   50篇
基础医学   283篇
口腔科学   89篇
临床医学   236篇
内科学   445篇
皮肤病学   19篇
神经病学   113篇
特种医学   36篇
外科学   202篇
综合类   37篇
预防医学   248篇
眼科学   18篇
药学   139篇
中国医学   13篇
肿瘤学   115篇
  2024年   3篇
  2023年   20篇
  2022年   50篇
  2021年   70篇
  2020年   52篇
  2019年   67篇
  2018年   56篇
  2017年   68篇
  2016年   57篇
  2015年   54篇
  2014年   96篇
  2013年   137篇
  2012年   193篇
  2011年   164篇
  2010年   81篇
  2009年   80篇
  2008年   123篇
  2007年   122篇
  2006年   111篇
  2005年   95篇
  2004年   84篇
  2003年   79篇
  2002年   80篇
  2001年   14篇
  2000年   16篇
  1999年   13篇
  1998年   17篇
  1997年   13篇
  1996年   15篇
  1995年   7篇
  1994年   11篇
  1993年   2篇
  1992年   2篇
  1991年   2篇
  1990年   2篇
  1988年   4篇
  1987年   8篇
  1986年   4篇
  1985年   4篇
  1984年   3篇
  1983年   3篇
  1982年   6篇
  1981年   4篇
  1979年   4篇
  1975年   5篇
  1974年   2篇
  1940年   1篇
  1938年   1篇
  1928年   1篇
  1927年   1篇
排序方式: 共有2122条查询结果,搜索用时 15 毫秒
91.
92.
This work aimed at evaluating the intragastric distribution of food in patients with GERD and dyspepsia and its relationship to acidic reflux episodes. Gastric emptying and food retention in the proximal stomach were evaluated by scintigraphy in 12 healthy subjects and 19 patients with GERD and dyspepsia after a liquid test meal. Patients also underwent 24-hr esophageal pH monitoring, which included a 2-hr postprandial period following a similar test meal. Total gastric emptying was similar in patients and controls, whereas proximal gastric retention (AUCprox/AUCtot) was significantly decreased in patients (mean +/- SD: 0.48 +/- 0.07 vs. 0.56 +/- 0.06; P = 0.02). Within the GERD-dyspepsia group, a significant negative correlation was found between proximal gastric retention and the number of acidic reflux episodes. We concluded that abnormally decreased retention of gastric contents in the proximal stomach after a liquid meal may contribute to the pathogenesis of acidic reflux episodes in patients with GERD and dyspepsia.  相似文献   
93.
94.
Objective(s):Investigate polymorphisms and expressions of human leukocyte antigen-G (HLA-G), galectin-1 (Gal-1), and interleukin-10 (IL-10) in people living with HIV (PLHIV) with and without comorbidities to help understanding the mechanisms involved in triggering these disorders in PLHIV and in their prognosis.Design:Here we evaluated the potential correlation between the genetic polymorphism and/or protein levels of HLA-G, Gal-1, and IL-10 with and without comorbidities of PLHIV.Methods:Two hundred HIV patients under antiretroviral treatment (83 with comorbidities and 117 without comorbidities) and 200 healthy individuals (controls) were genotyped, using PCR, for HLA-G 14-base pair polymorphism located at the 3’ untranslated region in exon 8 insertion/insertion (Ins/Ins: low HLA-G expression) or deletion/deletion (Del/Del: high HLA-G expression). Soluble levels of HLA-G (sHLA-G), Gal-1, and IL-10 were quantified by enzyme-linked immunosorbet assay.Results:HIV patients without comorbidities exhibited higher frequency of 14-base pair Del/Del genotype than HIV patients with comorbidities. As expected, HIV patients Ins/Ins with and without comorbidities produced less sHLA-G than controls. However, HIV patients Del/Del with comorbidities expressed sHLA-G more than controls and HIV patients Del/Del without comorbidities. Interestingly, patients that showed low levels sHLA-G, and presence of comorbidities, exhibited high Gal-1 serum levels. However, an increase in soluble levels of IL-10 in PLHIV was observed when compared to controls, especially in the PLHIV group without comorbidities suggesting, a protective role of IL-10 in the development of comorbidities.Conclusions:These data suggested that the high expression of sHLA-G and IL-10 or Gal-1 could be associated and could be associated with the development or not of comorbidities in PLHIV.  相似文献   
95.
96.
目的 探讨前交叉韧带(ACL)重建术后膝关节稳定性、功能及三维步态运动学情况.方法 回顾性分析2015年7月到2017年7月在佛山市中医院运动学科采用自体腘绳肌腱行ACL重建并进行了二次关节镜探查的270例病例,其中男164例,女106例.采用Lysholm评分、国际膝关节评分委员会(IKDC)评分、Tenger评分、...  相似文献   
97.
Elderly caregivers suffer physical and psychological consequences of the act of caring. The objective of this study was to characterize primary caregivers of elderly people in the community and identify the higher impacts of this activity on their life. We interviewed 127 caregivers about sociodemographic characteristics, presence of anxiety/depression (self-reporting questionnaire = SRQ), burden of care (caregiver burden scale = CBS); while their dependents were evaluated using sociodemographic questionnaires, health history, activities of daily living (ADL) scale and geriatric depression scale (GDS-15). The caregivers’ mean age was 55.1 ± 13.3 years; among them most were women and daughters with up to 4 years of education. The mean time as responsible for the elderly was 86.5 ± 96.3 months; 56% divided the caring responsibility and 28.2% had another occupation; 32.3% presented psychoemotional illness. There was a positive correlation between the CBS and the caregiver factors: psychoemotional disorders, time as responsible for the elderly and education level; as well as between the CBS and the elderly: number of activities with dependence, presence of depression and incontinences. The correlation between the elderly's personal income and number of visits received was negative. The identification of high impacts on the caregivers’ life would facilitate the professional approach.  相似文献   
98.
目的探讨第四代Oxford单髁置换术对膝关节内侧间室骨关节炎患者的临床疗效及对患者步态恢复的影响。方法将2016年1月至2018年1月收治并符合标准的30例(30膝)膝关节内侧间室骨关节炎患者纳入研究并作为试验组,另外再纳入20例(20膝)膝关节正常的志愿者作为本研究的正常组。试验组患者接受第四代Oxford单髁置换术,正常组研究对象不做任何治疗干预,仅作为观测指标对照。本研究观测指标主要包括疼痛视觉模拟评分(VAS评分)、膝关节学会评分系统(KSS)、美国WOMAC骨关节炎指数评分、美国特种外科医院膝关节评分(HSS评分)和步态分析运动学参数。比较试验组在术前、术后6个月及术后12个月的观测指标的差异,并分别与正常组作比较。结果试验组患者术前、术后6个月及术后12个月3个时间段两两之间的VAS评分、HSS评分、WOMAC评分以及KSS评分比较,差异均具有统计学意义(0.05)。试验组患者术前、术后6个月及术后12个月的步态分析各运动学参数的差异均具有统计学意义(0.05)。其中除最大前位移和最大内位移在术后6个月及术后12个月两个时间段差异无统计学意义之外,其他步态分析各运动学参数在3个时间段两两之间差异均具有统计学意义(0.05);试验组患者在术后12个月与正常组步态分析各运动学参数相比,最大伸直角、最大内位移和最大外位移比较,差异无统计学意义(0.05),但其余各步态分析各运动学参数差异仍然存在统计学意义(0.05)。结论在选择适当的病例和严格掌握手术适应证的前提下,第四代Oxford单髁置换术对膝关节内侧间室骨关节炎患者的近、中期疗效满意,术后患者关节功能更接近生理状态。  相似文献   
99.
100.
目的 探讨周围型肺癌CT表现与血清细胞角蛋白19片段(CYFRA21-1)滴度的关系.资料与方法 回顾性分析48例周围型肺癌CT表现与血清CYFRA21-1滴度资料,对比分析CT表现与血清CYFRA21-1滴度的关系.结果 28例瘤体直径≥3cm肺癌血清CYFRA21-1滴度(7.24±3.50) ng/ml,20例瘤体直径<3cm肺癌血清CYFRA21-1滴度(4.80±4.18)ng/ml,两组血清CYFRA21-1滴度差异有统计学意义(P<0.05).4例伴有空洞肺癌血清CYFRA21-1滴度(8.39±4.14)ng/m1,44例无空洞肺癌血清CYFRA21-1滴度(6.13±4.00)ng/ml,两组血清CYFRA21-1滴度差异有统计学意义(P<0.001).肺癌有无深"分叶征"、"胸膜凹陷征"、"毛刺征"、支气管气相、增强CT值≥20HU,"空泡征"、"毛玻璃征"、肺门或纵隔淋巴结增大与其血清CYFRA21-1滴度差异无统计学意义(P>0.05).结论 肺癌瘤体大小和空洞与其血清CYFRA21-1滴度有一定关系,瘤体直径≥3cm或伴有空洞的肺癌血清CYFRA21-1滴度较瘤体直径<3cm或无空洞的肺癌高.  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