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   3457篇
  免费   174篇
  国内免费   32篇
耳鼻咽喉   30篇
儿科学   90篇
妇产科学   47篇
基础医学   320篇
口腔科学   22篇
临床医学   265篇
内科学   632篇
皮肤病学   44篇
神经病学   619篇
特种医学   84篇
外科学   927篇
综合类   12篇
预防医学   168篇
眼科学   25篇
药学   139篇
中国医学   5篇
肿瘤学   234篇
  2023年   28篇
  2022年   43篇
  2021年   85篇
  2020年   56篇
  2019年   99篇
  2018年   91篇
  2017年   77篇
  2016年   80篇
  2015年   111篇
  2014年   146篇
  2013年   154篇
  2012年   239篇
  2011年   273篇
  2010年   169篇
  2009年   124篇
  2008年   208篇
  2007年   217篇
  2006年   191篇
  2005年   170篇
  2004年   160篇
  2003年   150篇
  2002年   128篇
  2001年   63篇
  2000年   67篇
  1999年   59篇
  1998年   32篇
  1997年   26篇
  1996年   30篇
  1995年   21篇
  1994年   20篇
  1993年   25篇
  1992年   42篇
  1991年   31篇
  1990年   40篇
  1989年   33篇
  1988年   22篇
  1987年   28篇
  1986年   16篇
  1985年   14篇
  1984年   13篇
  1983年   12篇
  1982年   7篇
  1981年   4篇
  1980年   5篇
  1979年   9篇
  1978年   6篇
  1977年   5篇
  1976年   5篇
  1975年   5篇
  1966年   6篇
排序方式: 共有3663条查询结果,搜索用时 31 毫秒
91.
Trisolini R  Livi V  Lazzari Agli L  Patelli M 《Lung》2012,190(2):249-250
Prevalence, characteristics and the very existence of neurofibromatosis-associated diffuse lung disease remain unclear, mostly because the few studies that looked at pulmonary involvement in such patients used chest X-ray as diagnostic mean. We report on the clinical, functional and HRCT findings in a patient with neurofibromatosis-associated diffuse lung disease and provide a short literature review.  相似文献   
92.
93.
94.
The aim of the study was to investigate the prevalence and persistence of syncytium-inducing (SI) strains in HIV-1-infected children along time of infection and to evaluate the influence of antiretroviral therapy and host factors on viral tropism. This is a retrospective analysis carried out in 267 HIV-1 vertically infected children from an Argentinean cohort. The viral phenotype was screened in MT-2 cells and coreceptor usage confirmed by the GHOST cell assay. Also, CD4(+) T cell count, viral load, antiretroviral therapy, and human CCR5-Δ32 and CCR2-64I genotypes were analyzed. A high frequency of HIV-1 SI/CXCR4-using variants (22%) was found among children within the first trimester of life, reaching 46% after 10 years of infection. At acute infection, zidovudine prophylaxis did not significantly affect the proportions of SI HIV-1 strains, while their presence was favored by the CCR5(+)/Δ32 genotype. Interestingly, the majority of the early SI strains did not persist over time, probably due to a higher susceptibility to antiretroviral (ARV) treatment or immunologic pressure. At the chronic stage, SI variants emerged even in the presence of HAART reaching 36% at 120 months of infection. Also the HIV-1 SI phenotype was associated with lower CD4(+) T cell counts all along the course of infection. These findings highlight the need to evaluate the presence of SI/CXCR4 variants early at primary infection. This will make it possible to optimize the use of CCR5 inhibitors in children who are apparently carriers of the R5 virus preventing early therapeutic failure due to the reemergence of SI strains from reservoirs.  相似文献   
95.
Stent thrombosis (ST) is the most dramatic complication of coronary stenting. Mechanisms of ST are multiple, including procedural and patient-related factors. A considerable burden of metal inside the coronary has been associated with ST as suggested by the higher rate of ST in case of multiple overlapping or complex two stents procedure in bifurcation lesions. However, occasional stent loss and failure to retrieve it may be a substrate of ST, especially if multiple layers of stent struts are incompletely crushed. Here, we describe a case of very late ST on a partially crushed stent previously lost inside the coronary circulation, using optical coherence tomography (OCT) for guidance during the procedure.  相似文献   
96.
97.

Purpose

To investigate gender differences in clinicopathological features and to analyze the prognostic impact of gender in renal cell carcinoma (RCC) patients undergoing surgery.

Methods

A total of 6,234 patients (eleven centers; Europe and USA) treated by radical or partial nephrectomy were included in this retrospective study (median follow-up 59 months; IQR 30–106). Gender differences in clinicopathological parameters were assessed. Multivariable Cox regression models were applied to determine the influence of parameters on disease-specific survival (DSS) and overall survival (OS).

Results

A total of 3,751 patients of the study group were male patients (60.2 %), who were significantly younger at diagnosis and received more frequently NSS than women. Significantly, more often high-grade tumors and simultaneous metastasis were present in men. Whereas tumor size and pTN stages did not differ between genders, clear-cell and chromophobe RCC was diagnosed less frequently, but papillary RCC more often in men. Gender also independently influenced DSS (HR 0.75, p < 0.001) and OS (HR 0.80, p < 0.001) with a benefit for women. However, inclusion of gender in multivariable models did not significantly gain predictive accuracies (PA) for DSS (0.868–0.870, p = 0.628) and OS (0.775–0.777, p = 0.522). Furthermore, no significantly different DSS and OS rates were found in patients undergoing NSS.

Conclusions

This study demonstrates important gender differences in clinicopathological features and outcome of RCC patients with improved DSS and OS for women compared to men, even if solely patients with clear-cell RCC or M0-stage are taken into evaluation. However, inclusion of gender in multivariable models does not significantly gain PA of multivariable models.  相似文献   
98.

Purpose

To compare two groups of patients who underwent two different arthroscopic procedures for repair of articular-sided partial-thickness rotator cuff tears (PTRCTs).

Materials this is a comparative prospective study of two methods for repair of partial cuff tears

Thirty-two patients underwent arthroscopic rotator cuff repair with a transtendon technique (group 1); 28 underwent arthroscopic full-thickness conversion and repair of the lesion (group 2). ROM measures, clinical findings, MRI features (tendon healing and re-tear), Constant–Murley and ASES scores were assessed pre- and postoperatively and compared. Patients were also asked about return to sport and level of activity.

Results

At the last appointment, patients of both the groups were significantly improved for clinical findings, ROM measures, imaging features, Constant–Murley and ASES scores than at baseline, without any significant inter-group difference. In group 1, 15 of 20 patients (75 %) who practiced recreational sport activities had returned to sport at the same level as before the onset of symptoms, without any discomfort. In group 2, 12 of 18 patients (67 %) had returned to the same level of sport activity they practiced before symptoms. At the last follow up, MRI showed rotator cuff healing in 31 patients of Group 1 and 27 patients of Group 2 (p = 0.83).

Conclusions

The two procedures are safe, effective, and comparable.  相似文献   
99.
100.
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