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   1416篇
  免费   143篇
  国内免费   3篇
耳鼻咽喉   26篇
儿科学   74篇
妇产科学   30篇
基础医学   248篇
口腔科学   33篇
临床医学   216篇
内科学   266篇
皮肤病学   24篇
神经病学   186篇
特种医学   35篇
外科学   88篇
综合类   3篇
一般理论   1篇
预防医学   89篇
眼科学   35篇
药学   116篇
肿瘤学   92篇
  2023年   9篇
  2022年   17篇
  2021年   26篇
  2020年   24篇
  2019年   40篇
  2018年   32篇
  2017年   40篇
  2016年   37篇
  2015年   34篇
  2014年   46篇
  2013年   80篇
  2012年   81篇
  2011年   73篇
  2010年   42篇
  2009年   64篇
  2008年   73篇
  2007年   69篇
  2006年   62篇
  2005年   83篇
  2004年   81篇
  2003年   61篇
  2002年   74篇
  2001年   34篇
  2000年   33篇
  1999年   37篇
  1998年   22篇
  1997年   28篇
  1996年   15篇
  1995年   19篇
  1994年   17篇
  1993年   23篇
  1992年   27篇
  1991年   26篇
  1990年   13篇
  1989年   16篇
  1988年   14篇
  1987年   19篇
  1986年   12篇
  1985年   7篇
  1984年   8篇
  1983年   5篇
  1982年   9篇
  1981年   4篇
  1980年   6篇
  1979年   7篇
  1978年   3篇
  1977年   3篇
  1970年   1篇
  1967年   1篇
  1962年   1篇
排序方式: 共有1562条查询结果,搜索用时 15 毫秒
101.
102.
The tolerability and kinetics of a solvent-detergent-treated 6% intravenous immunoglobulin (IVIG) preparation were studied in 15 hypogammaglobulinaemia patients during 3–4 regular substitution infusions of 9–18 g, the mean dose being 359 mg/kg. The infusions were well tolerated, and the trough serum IgG levels achieved were comparable to two commercial IVIG preparations. The stepwise increase of the infusion rate up to 5 mg/kg/min and the use of this IVIG as a 12% solution were possible without serious adverse events in all the 6 studied hypogammaglobulinaemia patients. This greatly reduced the time needed for the infusions.  相似文献   
103.
The apolipoprotein E (APOE) polymorphism is associated with neurodegenerative diseases. Its role regarding psychiatric disorders is controversial. It has been suggested to affect antidepressant treatment response and response to electroconvulsive therapy (ECT). In the present study, the association between APOE polymorphism and response to ECT in 119 patients with major depressive disorder was investigated. Moreover, a relation between APOE polymorphism and the age of onset of depression as well as the cognitive outcome of ECT was studied. In the whole population, no association was found between APOE polymorphism and response to ECT. However, in nonpsychotic patients, the epsilon2 allele tended to be more frequent in responders than nonresponders. Earlier onset of depression was observed in the patients with epsilon4 allele in late-life depression. There was no association between the APOE genotype and the cognitive change caused by ECT in the population as a whole. In women, however, epsilon2 allele may play a protective and epsilon4 allele a deleterious role in cognition during ECT.  相似文献   
104.
The purpose of the study was to determine whether the use of a GABAergic antiepileptic drug (AED), tiagabine, affects color vision and contrast sensitivity. Twenty newly diagnosed patients with partial epilepsy (aged 19-72 years), receiving tiagabine as their initial monotherapy for 5-41 months were examined. Color vision was examined with the Standard Pseudoisochromatic Plates 2 (SPP2), with the Farnsworth-Munsell 100 Hue Test (FM100) and with the Color Vision Meter 712 (CVM) anomaloscope. Contrast sensitivity was measured with the Pelli-Robson letter chart. Three patients excluded from the color vision evaluation for congenital red-green color vision defects. Seven out of 17 patients (41%) had acquired color vision deficit examined with the FM100. The CVM anomaloscope revealed minor defects in two patients. Contrast sensitivity function was within normal ranges. The present study suggests that AED therapy with tiagabine, like with other established and newer AEDs may interfere with color perception.  相似文献   
105.
Serum tryptase levels in acute coronary syndromes   总被引:2,自引:0,他引:2  
BACKGROUND: Mast cell accumulation and activation have been demonstrated in the vulnerable shoulder regions of atherosclerotic plaques and at the actual sites of plaque erosion and rupture. When activated and degranulated, mast cells release tryptase, a neutral protease, capable of activating matrix metalloproteinases and predisposing to plaque rupture. We tested the hypothesis that in acute coronary syndromes the levels of serum tryptase would reflect mast cell activation. METHODS AND RESULTS: The study population consisted of 183 patients admitted to the emergency room of 3 general hospitals because of acute chest pain of ischemic origin. Of these patients, 64 suffered from exertional angina presenting with acute chest pain, 60 had unstable angina, and 59 had acute myocardial infarction. Serum tryptase levels were analyzed from samples drawn, on average at 7 h, and also at 24 h after the onset of the chest pain. As controls served 41 patients admitted for surgical treatment of inguinal hernia or varicose veins. Serum tryptase levels remained stable within the observation period, and no differences were detected between the patient groups and controls. On the other hand, the differences in C-reactive protein levels reflected the extent of myocardial injury. CONCLUSIONS: In ACS, serum tryptase levels are normal and remain stable. Our results do not exclude the possibility of local activation of coronary mast cells, but suggest that the excess quantity of tryptase acutely released from mast cells in ACS, if any, is not sufficient to be detected by measuring tryptase concentration in the systemic circulation.  相似文献   
106.
Purpose: To evaluate whether radiological findings and healing time in children with pneumonia are correlated to etiologic agent.

Material and Methods: A total of 346 children with radiologically verified acute pneumonia, and with accomplished serological tests for bacteria and viruses, were included in the study. Five etiological groups were analysed: children with bacterial etiology only, with viral etiology only, with mixed bacterial and viral etiology, with Mycoplasma only, and children with no etiology.

Results: The chest films of each etiological group were analysed and the findings were correlated to the children's age. The radiological findings did not differ between the etiological groups. Radiological findings correlated significantly with the patient's age. The radiological healing frequency at check-up X-ray was found to be significantly lower in children with mixed bacterial and viral etiology compared to children in each of the other groups and to the material as a whole.

Conclusion: Conclusions about the etiology could not be drawn from the chest X-ray findings.  相似文献   
107.
This article summarizes the current status of 1H MRS in detecting and quantifying a boron neutron capture therapy (BNCT) boron carrier, L-p-boronophenylalanine-fructose (BPA-F) in vivo in the Finnish BNCT project. The applicability of 1H MRS to detect BPA-F is evaluated and discussed in a typical situation with a blood containing resection cavity within the gross tumour volume (GTV). 1H MRS is not an ideal method to study BPA concentration in GTV with blood in recent resection cavity. For an optimal identification of BPA signals in the in vivo 1H MR spectrum, both pre- and post-infusion 1H MRS should be performed. The post-infusion spectroscopy studies should be scheduled either prior to or, less optimally, immediately after the BNCT. The pre-BNCT MRS is necessary in order to utilise the MRS results in the actual dose planning.  相似文献   
108.
In adults, HLA haplotype B8-DRB1*03 is clearly associated with a severe clinical course of nephropathia epidemica caused by Puumala hantavirus. We investigated whether the same applies in pediatric patients. This HLA haplotype was found in 20 of 39 (51%) of the patients, a significantly higher figure than in the Finnish population (19%). There were, however, no significant differences in the clinical picture between patients with and without HLA B8-DRB1*03.  相似文献   
109.
Objective Glycodelin is a glycoprotein released by secretory/decidualized endometrial glands. Its synthesis increases during pregnancy. Hormonal factors whose levels have been shown to change in diabetes (vascular endothelial growth factor, relaxin) may mediate the actions or regulate the synthesis of glycodelin. Cord serum glycodelin levels have not been studied in pregnancies complicated by diabetes.Methods Cord serum glycodelin concentrations were measured at birth by an immunofluorometric assay in 62 normal pregnancies, in 67 pregnancies complicated by type 1 diabetes, and in 28 pregnancies complicated by insulin-treated gestational diabetes.Results The mean glycodelin concentration in cord serum was 2.7 ng/ml (standard error of the mean 0.6) in normal pregnancies. The concentration was not altered in pregnancies complicated by diabetes. Cord serum glycodelin concentrations were also unaltered in diabetic pregnancies with hypertensive disorders (chronic hypertension, pregnancy-induced hypertension or pre-eclampsia) or fetal macrosomia. There was a negative borderline correlation between cord serum glycodelin concentrations and the birth weight in pregnancies complicated by diabetes (r=–0.21, p=0.049).Conclusions Decidual function, as assessed by cord serum glycodelin levels, is not markedly altered in diabetic pregnancies. The negative correlation between cord serum glycodelin and the birth weight of the newborns in diabetic pregnancies may be due to the decline in glycodelin levels with advancing pregnancy in the third trimester.  相似文献   
110.
BACKGROUND: Study of the long-term effects of chronic alcohol consumption in human populations is confounded by genetic and environmental factors. METHODS: The study was intended to investigate the effects on morbidity and survival of lifetime forced ethanol consumption in male and female AA (Alko, Alcohol) and ANA (Alko, Non-Alcohol) rats. The ethanol-exposed rats had 12% ethanol as the only available fluid from 3 to 24 months of age. The control groups had water. Rats that died during the experiment and those that were killed at 24 months of age were all autopsied, and the pathologic findings were recorded. RESULTS: Lifelong ethanol consumption did not change the survival rate of the rats, and had no significant effect on the rates of any of the pathologic measures in either the AA or ANA line of rats, suggesting that this may not be a good animal model for studying the detrimental effects of chronic alcohol. An unexpected, highly significant finding was observed: the AA rats, bred for high voluntary ethanol drinking, lived much longer than the ANA rats, bred for ethanol avoidance. The death rate by 24 months in the AA line was less than one-third of that in the ANA line. This difference was found regardless of whether the animals were maintained on alcohol or water, and in both genders. The AA rats had significantly lower rates of kidney disease, benign tumors, and cardiovascular disease than the ANA animals. CONCLUSIONS: Lifelong ethanol consumption increased neither the mortality nor the morbidity of AA and ANA line of rats. Genes selected in the development of the high drinking AA line have additional effects producing rats that are healthier and living longer than the ANA rats possessing genes resulting in alcohol avoidance.  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