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   3209篇
  免费   108篇
  国内免费   20篇
耳鼻咽喉   25篇
儿科学   39篇
妇产科学   50篇
基础医学   446篇
口腔科学   42篇
临床医学   326篇
内科学   688篇
皮肤病学   16篇
神经病学   383篇
特种医学   93篇
外科学   516篇
综合类   5篇
一般理论   1篇
预防医学   180篇
眼科学   25篇
药学   263篇
中国医学   2篇
肿瘤学   237篇
  2023年   13篇
  2022年   26篇
  2021年   57篇
  2020年   25篇
  2019年   39篇
  2018年   71篇
  2017年   26篇
  2016年   45篇
  2015年   61篇
  2014年   97篇
  2013年   164篇
  2012年   219篇
  2011年   254篇
  2010年   114篇
  2009年   123篇
  2008年   241篇
  2007年   243篇
  2006年   243篇
  2005年   220篇
  2004年   221篇
  2003年   209篇
  2002年   227篇
  2001年   33篇
  2000年   39篇
  1999年   31篇
  1998年   50篇
  1997年   47篇
  1996年   23篇
  1995年   21篇
  1994年   21篇
  1993年   13篇
  1992年   17篇
  1991年   6篇
  1990年   14篇
  1989年   9篇
  1988年   8篇
  1987年   7篇
  1986年   8篇
  1985年   5篇
  1984年   9篇
  1983年   10篇
  1981年   3篇
  1980年   5篇
  1979年   4篇
  1978年   2篇
  1976年   2篇
  1975年   2篇
  1961年   1篇
  1960年   1篇
  1959年   2篇
排序方式: 共有3337条查询结果,搜索用时 15 毫秒
61.
Inotropic treatment remains the cornerstone for cardiogenic shock, an emergency that requires immediate resuscitative therapy before shock irreversibly damages vital organs. Although the sympathomimetic drug dobutamine is the most widely-used inotropic drug worldwide, it has several side effects including sinus tachycardia. Dobutamine partly restores systolic heart failure (HF); however, it increases the heart rate (HR) which counterbalances the beneficial effects. Ivabradine, a new selective If inhibitor, provides specific HR reduction and is indicated in stable coronary artery disease and in stable chronic HF with left ventricular dysfunction. Despite scarce data indicating beneficial effects of ivabradine in sinus tachycardia in various clinical settings, this drug remains contraindicated in acute HF. We propose that ivabradine could help to prevent the dobutamine-induced side effects, and that their combination in clinical practice could lead to pure inotropic effects, useful for the management of cardiogenic shock.  相似文献   
62.
63.
Digestive Diseases and Sciences - Abdominal pain is a cardinal sign of functional bowel disorders (FBD), in favor of irritable bowel syndrome (IBS). However, the determinants of abdominal pain...  相似文献   
64.
65.
This study aimed to determine the binding characteristics of [3H]α,β-Me-ATP, a specific ligand of the P2x1 receptors to rat platelets, and to investigate the effect of clopidogrel, a thienopyridine compound which has been found to selectively inhibit ADP-induced platelet aggregation and adenylyl cyclase ex vivo . Binding of [3H]α,β-Me-ATP to rat platelets was time-dependent and saturable. Scatchard analysis of the saturation binding data indicated that [3H]α,β-Me-ATP bound to one population of specific binding sites with high affinity ( K D  =  23.6 ± 1.6 n m ; B max = 690 ± 24 fmole/108cells) ( n= 3). Unlabelled α,β-Me-ATP as well as 2-MeS-ADP and ADP competitively inhibited the specific binding of [3H]α,β-Me-ATP with IC50 values of 19.0 ± 6.6, 103 ± 20 and 1120 ± 80 n m respectively ( n= 3). Other nucleotide analogues such as ATP, ATP-γS, UTP and GTP also antagonized [3H]α,β-Me-ATP binding. When administered orally (10 mg/kg, p.o.), clopidogrel inhibited ADP- or 2-MeS-ADP-induced platelet aggregation but did not affect the binding of [3H]α,β-Me-ATP to rat platelets ex vivo. In vitro , α,β-Me-ATP did not induce the aggregation or shape change of rat platelets and did not interfere with ADP-induced platelet aggregation.  相似文献   
66.
Objective: Emergency department (ED) triage for acute cardiac ischemia in the primary teaching hospital in Geneva, Switzerland, is very accurate, but at the cost of very long ED stays. Thus, the authors sought: 1) to determine the impact of the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI), incorporated into a computerized electrocardiograph, on length of stay and speed of triage decision making for ED patients presenting with symptoms suggesting acute cardiac ischemia, and 2) to study the ACI-TIPI’s impact on physicians of different training levels. Design: A seven-month prospective clinical trial with alternating-month experimental and control periods. Setting: An urban major teaching hospital in Geneva, Switzerland. Participants: Patients over the age of 18 years presenting to the ED with chest pain or other symptoms suggesting acute cardiac ischemia (acute myocardial infarction or unstable angina pectoris). Emergency department physicians, classified as novice (those in their first ED rotations) and experienced (those in their second or later ED rotations). Patients staying overnight in the ED (n=111) were excluded from the analysis. Intervention: During the experimental months, the computerized electrocardiograph printed the ACI-TIPI probability of acute cardiac ischemia at the top of each subject’s electrocardiogram. During control months, the probability was not provided. Measurements and main results: Among the 418 study subjects, for patients with acute ischemia seen by novice clinicians, the use of the ACI-TIPI decreased ED time from presentation to triage decision and ED release by 0.7 hour (19%) (p=0.007). Subgroup analyses for patients with acute myocardial infarction, patients with unstable angina pectoris, and patients given thrombolytic therapy also showed analogous decreases in ED time consistent with this finding. Other key determinants of ED length of stay included: age, whether the coronary care unit was full, whether patients received thrombolytic therapy, and whether admission was during the night shift. The experimental and control groups did not differ in triage disposition appropriateness or mortality. Conclusions: For ED patients with acute cardiac ischemia evaluated by novice clinicians, the ACI-TIPI substantially speeded ED decision making and triage. The suggestion of an impact on different cardiac ischemia subgroups and mortality deserves further larger clinical trials.  相似文献   
67.
AIM: The aim of this study was to evaluate the practice of colonoscopy and sigmoidoscopy in France in 2000. METHODS: A prospective study was conducted in November 2000 using questionnaires sent to all gastroenterologists practicing in France (N=2858) who were asked to reply to items concerning colonoscopies and sigmoidoscopies performed on two workdays chosen in advance. The response rate was 32.8%. Data were extrapolated to establish estimates for the entire year. RESULTS: An estimated 894000 colonoscopies and 115320 sigmoidoscopies were performed in 2000. Single-use material was used in 22.1% of the procedures. Indications for endoscopy were mainly hematochezia (21.6%), gastrointestinal symptoms (35%) and surveillance of patients with a history of previous polypectomy (15%). Colorectal cancer screening was the indication for 20% of colonoscopies. Abnormal findings were reported for 54.8% of the endoscopies (polyps for 287218 procedures and cancer for 32799). Failure was noted in 4.9% of colonoscopies. The complication rate was 0.48%. Most polyps were adenomas (64.4%) or hyperplasic polyps (28.1%). The overall estimated number of colonoscopies with polypectomy was 224133. CONCLUSION: In 2000 there was an increased rate of colonoscopy for colorectal cancer screening (20%) but an overall decrease (2.5%) in the total number of colonoscopies compared to 1999. Abnormal findings were disclosed by 54.8% of the procedures. Extrapolation from these data indicates that colonoscopic screening enabled the diagnosis of 32799 colorectal cancers.  相似文献   
68.
69.
Allergic rhinitis (AR) is impacted by allergens and air pollution but interactions between air pollution, sleep and allergic diseases are insufficiently understood. POLLAR (Impact of air POLLution on sleep, Asthma and Rhinitis) is a project of the European Institute of Innovation and Technology (EIT Health). It will use a freely-existing application for AR monitoring that has been tested in 23 countries (the Allergy Diary, iOS and Android, 17,000 users, TLR8). The Allergy Diary will be combined with a new tool allowing queries on allergen, pollen (TLR2), sleep quality and disorders (TRL2) as well as existing longitudinal and geolocalized pollution data. Machine learning will be used to assess the relationship between air pollution, sleep and AR comparing polluted and non-polluted areas in 6 EU countries. Data generated in 2018 will be confirmed in 2019 and extended by the individual prospective assessment of pollution (portable sensor, TLR7) in AR. Sleep apnea patients will be used as a demonstrator of sleep disorder that can be modulated in terms of symptoms and severity by air pollution and AR. The geographic information system GIS will map the results. Consequences on quality of life (EQ-5D), asthma, school, work and sleep will be monitored and disseminated towards the population. The impacts of POLLAR will be (1) to propose novel care pathways integrating pollution, sleep and patients’ literacy, (2) to study sleep consequences of pollution and its impact on frequent chronic diseases, (3) to improve work productivity, (4) to propose the basis for a sentinel network at the EU level for pollution and allergy, (5) to assess the societal implications of the interaction. MASK paper N°32.  相似文献   
70.
Lung ultrasound (LUS) increases clinical diagnosis performance in intensive care unit (ICU). Real-time three-dimensional (3-D) imaging was compared with two-dimensional (2-D) LUS by assessing the global diagnosis concordance. In this single center, prospective, observational, pilot study, one trained operator performed a 3-D LUS immediately after a 2-D LUS in eight areas of interest on the same areas in 16 ventilated critically ill patients. All cine loops were recorded on a computer without visible link between 2-D and 3-D exams. Two experts blindly reviewed cine loops. Four main diagnoses were proposed: normal lung, consolidation, pleural effusion and interstitial syndrome. Fleiss κ and Cohen’s κ values were calculated. In 252 LUS cine loops, the concordance between 2-D and 3-D exams was 83.3% (105/126), 77.6% (99/126) and 80.2% (101/126) for the trained operator and the experts respectively. The Cohen’s κ coefficient value was 0.69 [95% Confidence Interval (CI) 0.58–0.80] for expert 1 meaning a substantial agreement. The inter-rater reliability was very good (Fleiss’ κ value?=?0.94 [95% CI 0.87–1.0]) for 3-D exams. The Cohen’s κ was excellent for pleural effusion (κ=?0.93 [95% CI 0.76–1.0]), substantial for normal lung diagnosis (κ?=?0.68 [95% CI 0.51–0.86]) and interstitial syndrome (κ?=?0.62 [95% CI 0.45–0.80]) and fair for consolidation diagnoses (κ?=?0.47 [95% CI 0.30–0.64]). In ICU ventilated patients, there was a substantial concordance between 2-D and 3-D LUS with a good inter-rater reliability. However, the diagnosis concordance for lung consolidation is poor.  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