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   979篇
  免费   72篇
  国内免费   10篇
耳鼻咽喉   2篇
儿科学   19篇
妇产科学   29篇
基础医学   98篇
口腔科学   35篇
临床医学   83篇
内科学   224篇
皮肤病学   32篇
神经病学   102篇
特种医学   13篇
外科学   139篇
综合类   17篇
预防医学   91篇
眼科学   2篇
药学   65篇
  1篇
中国医学   3篇
肿瘤学   106篇
  2023年   9篇
  2022年   18篇
  2021年   20篇
  2020年   20篇
  2019年   16篇
  2018年   33篇
  2017年   16篇
  2016年   18篇
  2015年   26篇
  2014年   21篇
  2013年   42篇
  2012年   70篇
  2011年   53篇
  2010年   33篇
  2009年   40篇
  2008年   39篇
  2007年   68篇
  2006年   45篇
  2005年   52篇
  2004年   44篇
  2003年   48篇
  2002年   30篇
  2001年   37篇
  2000年   30篇
  1999年   38篇
  1998年   22篇
  1997年   8篇
  1996年   5篇
  1995年   5篇
  1994年   4篇
  1993年   3篇
  1992年   15篇
  1991年   14篇
  1990年   8篇
  1989年   7篇
  1988年   8篇
  1987年   10篇
  1986年   11篇
  1985年   11篇
  1984年   3篇
  1983年   9篇
  1982年   3篇
  1981年   4篇
  1980年   6篇
  1979年   5篇
  1976年   3篇
  1975年   3篇
  1970年   4篇
  1966年   4篇
  1965年   3篇
排序方式: 共有1061条查询结果,搜索用时 15 毫秒
11.
Latex allergy has become a real problem among both surgical staff (paramedics and physicians) and patients especially pediatric patients with urogenital malformations and spina bifida. Latex allergy is produced from both natural molecules which compose the substance produced from Hevea brasiliensis (rubber tree) and industrial additives contents in latex devices. Diagnosis of latex allergy may be carried out through a preoperative Prik-test. A characteristic of latex allergy reaction is the starting of symptoms (more than 15 minutes after allergen contact). Pathophysiology of latex allergy is the same of all allergic reactions; it is an antigen-antibody reaction and type I or II reaction may occur. There are a lot of devices that surgeons and anesthesists use in the operative theatre and that should not be used in presence of a patient with latex allergy. Guaranteed latex-free devices should always be present in store.  相似文献   
12.
n = 56) had an occluded contralateral carotid artery, in group II (n= 56) both carotids were operated on, and group III (n= 112) had a normal contralateral carotid artery. The clinical status of all patients except one was ascertained by one of us. We found that the status of the contralateral artery does not influence the long-term prognosis of patients undergoing carotid artery surgery. A periodic cardiological and vascular follow-up of these patients seems warranted to improve their survival.  相似文献   
13.
14.
We evaluated somatic genetic alterations in the kinase domain of the EGFR gene in the tumors of 219 non-small cell lung cancer patients of primarily Caucasian and African American origins. We identified 26 patients (12%) whose tumors had a mutation in the EGFR gene, and 11 (5%) patients carried novel genomic variations consistent with germ-line polymorphisms. All but one mutation were identified in Caucasian patients affected with adenocarcinoma. EGFR mutations were more frequent in women and in nonsmokers, but a significant portion of the affected patients were men (12 of 26) and current or past smokers accounted for half of the patients affected (13 of 26). Screening subjects with EGFR mutations may identify patients whose tumors could respond to targeted therapy using tyrosine kinase inhibitors.  相似文献   
15.
16.
Study designRandomized clinical trial.IntroductionAlthough orthotic immobilization has become the preferable treatment choice for closed mallet injuries, it is unclear whether orthosis self-removal has an impact on the final outcome.PurposeTo evaluate the treatment efficacy of cast immobilization of closed mallet fingers using Quickcast® (QC) compared to a removable, lever-type thermoplastic orthosis (LTTP).Methods57 subjects were randomized in 2 groups. DIPj extensor lag and the Gaberman success scale were used as primary outcomes.ResultsLTTP subjects resulted in greater extensor lag than QC subjects (x = 5°; p = 0.05) at 12 weeks from baseline, and high edema and older age negatively affected DIPj extensor lag. No other differences were found between groups.ConclusionCast immobilization seems to be slightly more effective than the traditional approach probably for its greater capacity to reduce edema.Level of evidence1B.  相似文献   
17.
OBJECTIVES: The study compared the prognostic value of dipyridamole and dobutamine stress echocardiography in patients with known or suspected coronary artery disease. BACKGROUND: Extensive information is available on the relative diagnostic accuracy of the two tests assessed in a head-to-head fashion, whereas comparative data on their prognostic yield are largely preliminary to date. METHODS: Dipyridamole (up to 0.84 mg/kg over 10 min) atropine (up to 1 mg over 4 min) (DIP) and dobutamine (up to 40 microg/kg/min)-atropine (1 mg over 4 min) (DOB) stress tests were performed in 460 patients with known or suspected coronary artery disease. Patients were followed up for 38+/-21 months. RESULTS: The DIP was negative in 253 and positive in 207 patients. The DOB was negative in 242 and positive in 218 patients. During the follow-up, there were 80 cardiac events. For all cardiac events, the negative and positive predictive value were 83% and 17% for DOB, 84% and 19% for DIP, respectively (p = NS). Considering only cardiac death, by univariate analysis Wall-Motion Score Index (WMSI) at DIP peak dose (chi-square 13.80, p<0.0002) was the strongest predictor, followed by WMSI DOB (chi2 = 8.02, p<0.004) and WMSI at rest (chi2 = 6.85, p<0.008). By stepwise analysis, WMSI at DIP peak dose was the most important predictor (RR [relative risk] 7.4, p<0.0001). CONCLUSIONS: In patients at low-to-moderate risk of cardiac events, pharmacological stress echocardiography with either dobutamine or dipyridamole allows effective and grossly comparable, risk stratification on the basis of the presence, severity and extension of the induced ischemia.  相似文献   
18.
Within an ongoing multicentre phase 3 randomised trial (ELDA, cancertrials.gov ID: NCT00331097), early breast cancer patients, 65-79 years old, with average to high risk of recurrence, are randomly assigned to receive CMF (cyclophosphamide 600 mg/m2, methotrexate 40 mg/m2, fluorouracil 600 mg/m2, days 1-8) or docetaxel (35 mg/m2 days 1-8-15), every 4 weeks. Here we report an unplanned safety analysis prompted by an amendment introducing creatinine clearance as a tool to adjust methotrexate dose. Before such change, 101 patients with a median age of 70 were randomly assigned CMF (53 patients) or docetaxel (48 patients). At least one grades 3-4 toxic event of any type was reported in 40 (75.5%) and 19 (39.6%) patients with CMF and docetaxel, respectively (p=0.0002). Grades 3-4 hematological events were observed in 37 (69.8%) vs. 4 (8.3%) cases (p<0.0001) and grades 3-4 non-hematological toxicity in 12 (22.6%) vs. 15 (31.2%) patients (p=0.11), with CMF and docetaxel, respectively. A higher incidence of anemia, neutropenia, thrombocytopenia and febrile neutropenia was reported with CMF. Constipation, mucositis, nausea and vomiting were more common with CMF; diarrhoea, abdominal pain, dysgeusia, neuropathy and liver toxicity were more frequent with docetaxel. No significant interaction was found between the occurrence of severe toxicity and baseline variables, including creatinine clearance and geriatric activity scales. In conclusion, weekly docetaxel appears to be less toxic than CMF in terms of hematological toxicity.  相似文献   
19.
Body mass index and mortality among hospitalized patients   总被引:5,自引:0,他引:5  
BACKGROUND: Body mass index (weight in kilograms divided by the square of the height in meters [BMI]) is known to be associated with overall mortality. However, the effect of age on excess mortality from all causes associated with obesity is controversial. The aim of the present study is to determine the effect of age on the relationship between BMI and mortality. METHODS: We analyzed data from a large collaborative observational study group, the Italian Group of Pharmacoepidemiology in the Elderly (GIFA), that collected data on hospitalized patients. A total of 18,316 patients consecutively admitted to 79 clinical centers during 5 different surveys in 1998, 1991, 1993, 1995, and 1997 were enrolled in the present study. The main outcome measure was the relative hazard ratio of death for different levels of BMI. RESULTS: Mortality rate was lowest among men and women with BMIs from 25.0 through 27.4 kg/m(2) (relative risk, 0.24; 95% confidence interval, 0.15-0.38). The graphed relationship between BMI and mortality in younger patients was hyperbolic, with increased death rates at the lowest and highest BMI rankings. On the contrary, the older patients showed an increased death rate at the lowest BMIs with only a slight elevation at the highest BMIs (>35 kg/m(2)). CONCLUSIONS: Our results suggest that BMI, a simple anthropometric measure of nutritional status, is an important predictor of mortality among young and old hospitalized patients. Even when controlling for clinical and functional variables, a low BMI remained a significant and independent predictor of shortened survival. Furthermore, the finding of the high BMI associated with minimum hazard in elderly subjects supports some past findings and opposes others and, if confirmed, has important implications for geriatric clinical guidelines.  相似文献   
20.
BACKGROUND: Moderate alcohol consumption has been associated in several studies with decreased risk of cardiovascular and cerebrovascular events; however, available data on the effects of alcohol intake on cognitive functioning are conflicting. We assessed the association between alcohol consumption and cognitive impairment in a series of older subjects enrolled in a multicenter pharmacoepidemiology survey. METHODS: The association between average alcoholic intake and cognitive performance was assessed in 15,807 patients admitted to participating centers during the survey periods. Demographic variables, comorbid conditions, medications, and objective tests that were associated with cognitive impairment (as indicated by a Hodkinson Abbreviated Mental Test score <7) in separate logistical regression models were examined as potential confounders in a summary model. RESULTS: Cognitive impairment was detected in 1693 (19%) of 8755 drinkers and 2008 (29%) of 7052 nondrinkers (Fisher's exact test, p < 0.0001). After adjusting for potential confounders, alcohol consumption was associated with decreased probability of cognitive impairment (odds ratio, 0.75; 95% confidence interval, 0.66-0.85). The relationship between drinking level and cognitive dysfunction was nonlinear, because the probability of cognitive impairment was decreased for moderate alcohol use as compared with abstinence, but it was increased for daily consumption exceeding one wine-equivalent liter among men and 0.5 liter among women. This nonlinear association persisted when cerebrovascular and Alzheimer's disease were considered separately. CONCLUSIONS: Alcohol abuse is associated with increased prevalence of cognitive dysfunction among older subjects; however, a daily alcohol consumption of less than 40 g for women and 80 g or less for men might be associated with a decreased probability of cognitive impairment. This possible protective effect of alcohol consumption should be further assessed by prospective studies.  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