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   1250篇
  免费   62篇
  国内免费   8篇
耳鼻咽喉   6篇
儿科学   97篇
妇产科学   29篇
基础医学   98篇
口腔科学   40篇
临床医学   87篇
内科学   349篇
皮肤病学   51篇
神经病学   70篇
特种医学   105篇
外科学   151篇
综合类   26篇
预防医学   39篇
眼科学   63篇
药学   75篇
中国医学   1篇
肿瘤学   33篇
  2023年   3篇
  2022年   9篇
  2021年   26篇
  2020年   9篇
  2019年   6篇
  2018年   14篇
  2017年   14篇
  2016年   25篇
  2015年   23篇
  2014年   42篇
  2013年   70篇
  2012年   54篇
  2011年   44篇
  2010年   61篇
  2009年   62篇
  2008年   66篇
  2007年   54篇
  2006年   66篇
  2005年   70篇
  2004年   54篇
  2003年   41篇
  2002年   53篇
  2001年   40篇
  2000年   35篇
  1999年   39篇
  1998年   41篇
  1997年   29篇
  1996年   26篇
  1995年   18篇
  1994年   24篇
  1993年   26篇
  1992年   14篇
  1991年   10篇
  1990年   9篇
  1989年   14篇
  1988年   20篇
  1987年   11篇
  1986年   14篇
  1985年   9篇
  1984年   12篇
  1983年   6篇
  1982年   9篇
  1981年   12篇
  1980年   12篇
  1978年   4篇
  1977年   5篇
  1976年   9篇
  1975年   2篇
  1957年   1篇
  1955年   1篇
排序方式: 共有1320条查询结果,搜索用时 15 毫秒
21.
Temporal artery biopsy is considered the gold standard investigation of giant cell arteritis and is recommended in suspected cases despite a sensitivity of 81–91%. This review highlights the potential risk of facial nerve injury during temporal artery biopsy and introduces recent advances in the emerging role of imaging modalities. When these non-invasive techniques are used in conjunction with American College of Rheumatology scoring, which includes clinical features and biochemical test results, temporal artery biopsy may be avoided in selected cases.  相似文献   
22.

Introduction

Magnetic resonance cholangiopancreatography (MRCP) is not a routine investigation to exclude choledocholithiasis unless there is clinical or biochemical suspicion of common bile duct (CBD) stones. This study attempted to determine which radiological or serological parameters best predicted CBD stones.

Methods

All patients undergoing MRCP from 2005 to 2011 were selected. Patients with pancreatitis were excluded. Liver function tests (LFTs) at admission and prior to MRCP were recorded, as was abdominal ultrasonography and MRCP results. Parameters measured routinely on LFTs included alkaline phosphatase (ALP), alanine transaminase (ALT) and bilirubin. Receiver operating characteristic curve area analysis (area under the curve [AUC]) and chi-squared analysis were undertaken.

Results

Overall, 195 patients were identified, 71 of whom had CBD stones on MRCP. Raised ALP levels on admission demonstrated a correlation with CBD stones (AUC: 0.619, odds ratio [OR]: 3.16, p=0.06). At ultrasonography, a dilated CBD (OR: 3.76, p<0.001) and intrahepatic duct dilation (OR: 5.56, p<0.001) were highly significant predictors. However, only 37% of patients had a dilated CBD on ultrasonography. Ongoing elevation of LFT parameters, particularly ALP (AUC: 0.707, OR: 4.64, p<0.001) and ALT (AUC: 0.646, OR: 5.40, p<0.001), displayed a significant correlation with CBD stones.

Conclusions

Ongoing (even if minor) elevations of liver function test parameters should prompt the need to exclude CBD stones even in the presence of a normal CBD diameter on ultrasonography.  相似文献   
23.
Thrombin causes subsecond changes in protein phosphorylation of platelets   总被引:1,自引:0,他引:1  
Carty  DJ; Spielberg  F; Gear  AR 《Blood》1986,67(6):1738-1743
We have developed a general quenched-flow approach to study platelet function as early as 0.3 seconds after stimulation. Phosphorylation of 20- and 40-kd proteins has been analyzed during the first five seconds of platelet response to thrombin from 0.1 to 5.0 U/mL and compared with the progress of aggregation and serotonin secretion. The onset time for aggregation and phosphorylation of both proteins was less than one second, although with lowest (less than 0.5 U/mL) thrombin levels, a lag of up to 0.6 seconds occurred before 40K phosphorylation increased. The thrombin sensitivity of aggregation and 20K phosphorylation was approximately twice that of 40K phosphorylation, with Ka values of 0.51 and 0.53 v 1.10 U/mL, respectively. External calcium was necessary for maximal 20K phosphorylation, since EDTA inhibited this by 30%. The 40K phosphorylation was not affected by EDTA. Platelet activation by thrombin thus induced biochemical changes well before one second. The quenched-flow approach may help to reveal relationships between phospholipase activation, calcium fluxes, and protein phosphorylation during these early periods of platelet function.  相似文献   
24.
25.
According to World Health Organization, the life expectancy at birth is increasing. An increase in life expectancy might result in increased morbidity and mortality in elderly. The increase in the elderly population also leads to an increase in medico-legal problems, as well. Autopsy is of high importance for determination of cause of death in clinical and forensic cases. The purpose of this study was to find out general characteristics elderly deaths by examining forensic autopsy records.  相似文献   
26.
Haloperidol is commonly used in the treatment of psychiatric disorders. Data from animal experiments indicate haloperidol is not teratogenic, but is embryotoxic in high doses. For the first time, we report a neonate with transient nephrogenic diabetes insipidus (DI) caused by fetal exposure to haloperidol. The magnitude of risk associated with the use of haloperidol during pregnancy appears to be small, but nephrogenic DI secondary to haloperidol is a serious condition with the risk of hypernatremic dehydration. Haloperidol can have adverse effects on the fetus and newborn infant, that’s why one should prevent the use of haloperidol during pregnancy and lactation.  相似文献   
27.
Ventriculoperitoneal shunt application is among the most frequently performed procedure in the treatment of hydrocephalus. Despite the peritoneal cavity being convenient for absorption of cerebrospinal fluid, multiple complications related to the shunt tend to develop in this area. Anal migration of ventriculoperitoneal shunt catheter is seen as a rare complication due to the intestinal perforation caused by peritoneal shunt catheters. The diagnosis of this condition is self-evident. In this report, an infant whose shunt catheter protrudes through the anus with no abdominal or CNS signs is presented.  相似文献   
28.
29.
Discoid lupus erythematosus is a manifestation of chronic cutaneous lupus erythematosus with a small risk of systemic involvement. In this review article, the role of predisposing factors such as haplotype, hormones, antibodies and sunlight are discussed. The clinical features, including variants and associations, and management options are presented.  相似文献   
30.
Strain‐dependent induction of allergic rhinitis without adjuvant in mice   总被引:1,自引:0,他引:1  
BACKGROUND: To date, no murine models have been reported to show the induction of both antigen-specific IgE and nasal eosinophilia, two of the major hallmarks of allergic rhinitis, after local sensitization in the absence of adjuvants, a phenomenon which reflects natural exposure. In this report, we attempted to establish a murine model representing an initiation of allergic rhinitis. METHODS: BALB/c, CBA/J, and C57BL/6 mice were sensitized intranasally to Schistosoma mansoni egg antigen (SEA) solely. After repeated sensitization, serum Ab titers, nasal eosinophilia, and cytokine production by nasal lymphocytes were determined. RESULTS: BALB/c mice produced SEA-specific IgE after repeated sensitization. High-dose sensitization to SEA induced IgE production in CBA/J mice, while C57BL/6 mice did not show the production throughout the period observed, suggesting that IgE production was regulated genetically. BALB/c mice also exhibited nasal eosinophilia after the nasal challenge. In addition, nasal lymphocytes sensitized with SEA intranasally produced significant amount of IL-5 in vitro. CONCLUSIONS: These results suggest that intranasal sensitization with SEA in the absence of adjuvants induces a Th2 immune reaction, reflecting the hallmarks of the initiation of allergic rhinitis both in vivo and in vitro, which is genetically regulated.  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