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   876篇
  免费   76篇
  国内免费   11篇
耳鼻咽喉   3篇
儿科学   13篇
妇产科学   8篇
基础医学   173篇
临床医学   79篇
内科学   324篇
皮肤病学   5篇
神经病学   112篇
特种医学   56篇
外科学   87篇
综合类   1篇
预防医学   29篇
眼科学   2篇
药学   40篇
中国医学   1篇
肿瘤学   30篇
  2024年   4篇
  2023年   7篇
  2022年   11篇
  2021年   20篇
  2020年   18篇
  2019年   32篇
  2018年   25篇
  2017年   19篇
  2016年   28篇
  2015年   31篇
  2014年   33篇
  2013年   38篇
  2012年   71篇
  2011年   82篇
  2010年   30篇
  2009年   34篇
  2008年   45篇
  2007年   52篇
  2006年   52篇
  2005年   39篇
  2004年   48篇
  2003年   38篇
  2002年   36篇
  2001年   9篇
  2000年   8篇
  1999年   8篇
  1998年   12篇
  1997年   12篇
  1996年   13篇
  1995年   12篇
  1994年   11篇
  1993年   7篇
  1992年   5篇
  1991年   5篇
  1990年   7篇
  1989年   4篇
  1988年   5篇
  1987年   5篇
  1986年   5篇
  1985年   3篇
  1984年   3篇
  1982年   2篇
  1981年   2篇
  1976年   4篇
  1975年   9篇
  1974年   2篇
  1973年   2篇
  1972年   2篇
  1971年   5篇
  1965年   1篇
排序方式: 共有963条查询结果,搜索用时 15 毫秒
31.
Psychogenic nonepileptic seizures (PNES) are paroxysmal clinical events that are often misdiagnosed as epileptic seizures, but which are not associated with electrographic discharge. Brain connectivity changes occurring during PNES are not known. We studied functional connectivity (Fc) in two patients with drug-resistant epilepsy, explored by stereotactic electroencephalography (EEG), in whom we recorded both epileptic seizures (ES) and PNES. Functional connectivity using pair-wise nonlinear correlation was computed between signals from seven brain areas: amygdala, hippocampus, lateral temporal cortex, anterior insula, orbitofrontal cortex, prefrontal cortex, and lateral parietal cortex. We assessed changes in global Fc during PNES in comparison with a background period. During PNES, a global decrease of Fc occurred between the different brain regions studied, compared with the interictal period. In both patients, decreased Fc was prominent in connections involving the anterior insula and parietal cortex. In conclusion, some PNES are associated with ictal functional disconnection between brain areas, particularly involving the parietal cortices and the anterior insula.  相似文献   
32.

Background

Sigmoid volvulus is a common cause of colonic obstruction in old and frail patients. Its standard management includes the endoscopic detorsion of the colonic loop, followed by an elective sigmoidectomy to prevent recurrence. However, these patients are often poor candidates for surgery.

Aim

The aim of this study was to compare death rate between elective sigmoidectomy and conservative management following endoscopic detorsion for sigmoid volvulus.

Methods

The medical records of 83 patients undergoing endoscopic detorsion of a sigmoid volvulus from 2008 to 2014 were retrospectively reviewed. Patients were divided into two groups: ‘elective surgery’ and ‘no surgery’.

Results

Patients in the ‘no surgery’ group (n?=?42) were older and had more loss of autonomy than in the ‘elective surgery’ group. Volvulus endoscopic detorsion was successful in 96% of patients with no complications. The median follow-up was 13 months (1 day-67 months). The death rate was 62% in the ‘no surgery’ group versus 32% in the ‘elective surgery’ group (p?=?0.02). In the ‘no surgery’ group, 23/42 of patients had volvulus recurrence. No recurrence occurred after surgery.

Conclusion

Elective surgery must be planned as soon as possible after the first episode of sigmoid volvulus. In frail patients, other options must be developed.  相似文献   
33.
Tranexamic acid (TXA) is an antifibrinolytic drug that reduces surgical blood loss and death due to bleeding after trauma and post‐partum haemorrhage. One key issue for treatment success is early administration. While usually given intravenously, oral and intramuscular use would be useful in specific circumstances. Therefore, an understanding of TXA pharmacokinetics when given via different routes is valuable. The aim of this study was to perform an individual participant data meta‐analysis of pharmacokinetic studies with TXA given to healthy volunteers via different routes. We searched the following databases: PubMed, Web of Science, Wiley Online Library, Elsevier Science Direct and J‐STAGE. Individual subject data were extracted when available, otherwise arithmetic means were used. A population pharmacokinetic model was developed using nonlinear mixed effect modelling. Seven studies were included in the analysis with data from 10 patients for the IV route, six patients for the IM route and 114 patients for the oral route. The pharmacokinetics was ascribed to a two‐compartment model, and the main covariate was allometrically scaled bodyweight. Oral and IM bioavailabilities were 46 and 105%, respectively. For a 70 kg bodyweight, the population estimates were 7.6 L/h for clearance, 17.9 L for the volume of the central compartment, 2.5 L/h for the diffusional clearance and 16.6 L for the peripheral volume of distribution. Larger well‐designed studies are needed to describe the pharmacokinetics of TXA when given IM or as an oral solution before these can be recommended as alternatives to IV.  相似文献   
34.
35.
BACKGROUND/AIMS: To analyze the barriers to HCV treatment in HIV-HCV co-infected patients and their evolution between 2004 and 2006. METHODS: Three hundred and eighty HIV-HCV co-infected patients were prospectively included in surveys from November 22 to 29, 2004 (2004 survey), and 416 from April 3 to 10, 2006 (2006 survey). RESULTS: Patients in 2006 compared to those in 2004 had negative HCV RNA more often (24% vs. 12%). The rate of liver biopsy was similar (56% vs. 54%) while 24% had had a non-invasive liver damage assessment. The rate of previous treatment for HCV infection was higher (48% vs. 26%). The main reasons for HCV non-treatment have changed: HCV treatment deemed questionable (44% vs. 53%), lack of liver biopsy (18% vs. 33%), physicians' conviction of poor patient compliance (20% vs. 30%). In both surveys, HCV treated patients were more often of European origin, had better control of HIV infection, and had a liver damage assessment more often. CONCLUSIONS: The care of HIV-HCV co-infected patients has changed significantly in "real life". These results underline the importance of continuing efforts to educate physicians and patients in order to increase the access of co-infected patients to HCV treatment.  相似文献   
36.
The extent of occupational injuries among health care workers in central Africa, particularly in the Democratic Republic of Congo, is not documented. We sought to determine the incidence of percutaneous injury and exposure to blood and other body fluids in Congolese urban and rural hospitals in the previous year. Our data show high rates of percutaneous injury and exposure to blood and other body fluids, reflecting poor safety conditions for most Congolese health care workers.  相似文献   
37.
38.
In a multicenter open longitudinal clinical trial where 479 patients suffering from migraine with or without aura were recruited, patients treated at home one to three migraine attacks with their customary treatment, and subsequently, over a 3-month period, one to three migraine attacks with (5 mg sumatriptan sc using an auto-injector. The headache response to customary treatment was 19% at 1 h and 30.5% at 2 h, and was not significantly different when only attacks treated "adequately" according to accepted treatment recommendations were considered: 16% at 1 h and 35% at 2 h. In contrast, 69% and 82% of patients treated with 6 mg sumatriptan sc had mild headache or no headache at 1 and 2 h respectively, regardless of migraine type or duration of symptoms prior to treatment. Other migraine symptoms (nausea, vomiting, photo- and phonophobia) were effectively treated with sumatriptan. Recurrence of migraine was observed in 31% of patients and was well controlled by a second injection of sumatriptan. It is concluded that 6 mg sumatriptan sc, self-administered using an auto-injector, is well tolerated and more effective than most currently used acute treatments for migraine in a population of severely affected patients consulting a neurologist.  相似文献   
39.
40.
Beckwith–Wiedemann syndrome (BWS) is an imprinting disorder associating macroglossia, abdominal wall defects, visceromegaly, and a high risk of childhood tumor. Molecular anomalies are mostly epigenetic; however, mutations of CDKN1C are implicated in 8% of cases, including both sporadic and familial forms. We aimed to describe the phenotype of BWS patients with CDKN1C mutations and develop a functional test for CDKN1C mutations. For each propositus, we sequenced the three exons and intron–exon boundaries of CDKN1C in patients presenting a BWS phenotype, including abdominal wall defects, without 11p15 methylation defects. We developed a functional test based on flow cytometry. We identified 37 mutations in 38 pedigrees (50 patients and seven fetuses). Analysis of parental samples when available showed that all mutations tested but one was inherited from the mother. The four missense mutations led to a less severe phenotype (lower frequency of exomphalos) than the other 33 mutations. The following four tumors occurred: one neuroblastoma, one ganglioneuroblastoma, one melanoma, and one acute lymphoid leukemia. Cases of BWS caused by CDKN1C mutations are not rare. CDKN1C sequencing should be performed for BWS patients presenting with abdominal wall defects or cleft palate without 11p15 methylation defects or body asymmetry, or in familial cases of BWS.  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