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   1561篇
  免费   142篇
  国内免费   20篇
耳鼻咽喉   9篇
儿科学   119篇
妇产科学   20篇
基础医学   198篇
口腔科学   99篇
临床医学   148篇
内科学   281篇
皮肤病学   177篇
神经病学   37篇
特种医学   137篇
外科学   224篇
综合类   25篇
预防医学   79篇
眼科学   34篇
药学   47篇
  1篇
中国医学   2篇
肿瘤学   86篇
  2024年   5篇
  2023年   14篇
  2022年   13篇
  2021年   31篇
  2020年   21篇
  2019年   12篇
  2018年   48篇
  2017年   43篇
  2016年   37篇
  2015年   60篇
  2014年   70篇
  2013年   106篇
  2012年   56篇
  2011年   51篇
  2010年   73篇
  2009年   79篇
  2008年   39篇
  2007年   47篇
  2006年   53篇
  2005年   35篇
  2004年   34篇
  2003年   35篇
  2002年   31篇
  2001年   26篇
  2000年   23篇
  1999年   35篇
  1998年   90篇
  1997年   72篇
  1996年   83篇
  1995年   51篇
  1994年   63篇
  1993年   36篇
  1992年   14篇
  1991年   20篇
  1990年   11篇
  1989年   27篇
  1988年   22篇
  1987年   22篇
  1986年   20篇
  1985年   21篇
  1984年   11篇
  1983年   6篇
  1982年   15篇
  1981年   12篇
  1980年   12篇
  1979年   5篇
  1978年   5篇
  1977年   7篇
  1976年   10篇
  1975年   7篇
排序方式: 共有1723条查询结果,搜索用时 15 毫秒
71.
背景:非裔美国人发生脂溢性皮炎时可伴色素减退。治疗通常应用皮质激素和抗真菌药,然而长期使用皮质激素可导致皮肤萎缩,眼内压增高,或加重色素减退。吡美莫司已被成功用于治疗一些脂溢性皮炎患者。目的:此开放性预试验用于评估吡美莫司治疗非裔美国人中伴色素减退的脂溢性皮炎  相似文献   
72.
Vohwinkel syndrome (VS) is a family of genodermatoses which exhibits extensive clinical and genetic heterogeneity. Here, we studied a pedigree originating from the UK with typical features of the ichthyotic variant of VS and identified a recurrent insertion mutation in the loricrin gene resulting in a mutant polypeptide with an unusual C terminus. Functional studies in transgenic mice have shown that the accumulation of mutant loricrin in the nucleus appears to interfere with the later stages of epidermal differentiation, thereby explaining the clinical manifestations of ichthyosis, keratoderma and pseudoainhum. Our findings extend the body of evidence implicating mutations in the loricrin gene as the underlying cause of VS.  相似文献   
73.
74.
75.
Classification of familial amyloidosis by the chemical natureof the fibrillar protein has become possible. Most such amyloidogenicproteins so far recognized are variant transthyretins, but twokindreds with the same apolipoprotein AI modification have beenreported. We describe the clinical features of another suchfamily in whom petechial skin rash appeared to be a marker forthe disease, which was non-neuropathic and of the Ostertag-type.Immunohistochemistry showed the protein to be apolipoproteinAI, but allele-specific DNA amplification indicated that itwas not the Arg26 variant previously identified.  相似文献   
76.

Introduction

Bacterial contamination from viscerotomy is a barrier to natural orifice translumenal endoscopic surgery (NOTES). The aim of this survival study is to evaluate pure (totally) transvaginal NOTES bacterial contamination compared with laparoscopy in pigs.

Methods

Twelve adult female pigs underwent peritoneoscopy with liver and peritoneal biopsies, using either laparoscopy (Glap, six animals) or pure transvaginal (GNOTES) access, and were maintained alive for 7 days. In all animals, blood cultures were taken at baseline, and after 24 h and 7 days postoperatively. Swab cultures from vagina (GNOTES) and skin (Glap) were obtained pre- and post-antisepsis. Peritoneal fluid culture was obtained at necropsy. For statistical analysis, Glap and GNOTES were compared for presence of positive bacterial cultures (qualitative bacterial analysis) using Fisher’s test, with level of significance set at p < 0.05.

Results

All animals had good postoperative outcome. One animal had transient perioperative bleeding from a transvaginal access. Two animals in Glap and one in GNOTES had positive blood cultures after the procedure. All animals from GNOTES and Glap presented with mixed flora pre-antisepsis. After antisepsis, one animal (GNOTES) presented with a positive vaginal swab culture (a single bacterial strain was identified). There was no positive skin swab culture in Glap. There were no signs of intra-abdominal infection at necropsy. In two animals, one from Glap and another from GNOTES, intra-abdominal culture was positive for Corynebacterium spp. and Escherichia coli, respectively. There was no correlation between the bacterial flora found at the access site and in the peritoneal cultures.

Conclusions

Pure transvaginal peritoneoscopy with liver and peritoneal biopsy in swine is feasible and associated with bacterial contamination comparable to laparoscopy. Peritoneal bacterial contamination was clinically insignificant after 1 week postoperatively. Preoperative antisepsis provided significant reduction of bacterial load prior to transvaginal and laparoscopic procedures.  相似文献   
77.
78.
79.

Background

Clinical data on myocardial function in HCM mutation carriers (carriers) is sparse but suggests that subtle functional abnormalities can be measured with tissue Doppler imaging before the development of overt hypertrophy. We aimed to confirm the presence of functional abnormalities using cardiovascular magnetic resonance (CMR), and to investigate if sensitive functional assessment could be employed to identify carriers.

Results

28 carriers and 28 controls were studied. Global left atrial (LA) and left ventricular (LV) dimensions, segmental peak systolic circumferential strain (SCS) and peak diastolic circumferential strain rate (DCSR), as well as the presence of late Gadolinium enhancement (LGE) were determined with CMR. Septal and lateral myocardial velocities were measured with echocardiographic tissue Doppler imaging. lv mass and volumes were comparable between groups. Maximal septal to lateral wall thickness ratio (SL ratio) was larger in carriers than in controls (1.3 ± 0.2 versus 1.1 ± 0.1, p < 0.001). Also, LA volumes were larger in carriers compared to controls (p < 0.05). Both peak SCS (p < 0.05) and peak DCSR (p < 0.01) were lower in carriers compared to controls, particularly in the basal lateral wall. Focal LGE was present in 2 carriers and not in controls. The combination of a SL ratio >1.2 and a peak DCSR <105%.s-1 was present in 45% of carriers and in none of the controls, yielding a positive predictive value of 100%. Two carriers and 18 controls had a SL ratio < 1.2 and peak DCSR >105%.s-1, yielding a negative predictive value of 90%. With multivariate analysis, HCM mutation carriership was an independent determinant of reduced peak SCS and peak DCSR.

Conclusions

HCM mutation carriership is an independent determinant of reduced peak SCS and peak DCSR when LV wall thickness is within normal limits, and is associated with increased LA volumes and SL ratio. Using SL ratio and peak DCSR has a high accuracy to identify carriers. However, since carriers also display structural abnormalities and focal LGE, we advocate to also evaluate morphology and presence of LGE when screening for carriers.  相似文献   
80.
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