全文获取类型
收费全文 | 12906篇 |
免费 | 2882篇 |
国内免费 | 75篇 |
专业分类
耳鼻咽喉 | 216篇 |
儿科学 | 246篇 |
妇产科学 | 393篇 |
基础医学 | 768篇 |
口腔科学 | 522篇 |
临床医学 | 3769篇 |
内科学 | 2403篇 |
皮肤病学 | 378篇 |
神经病学 | 1141篇 |
特种医学 | 337篇 |
外科学 | 2288篇 |
综合类 | 86篇 |
一般理论 | 3篇 |
预防医学 | 1545篇 |
眼科学 | 492篇 |
药学 | 536篇 |
中国医学 | 35篇 |
肿瘤学 | 705篇 |
出版年
2024年 | 54篇 |
2023年 | 517篇 |
2022年 | 201篇 |
2021年 | 399篇 |
2020年 | 497篇 |
2019年 | 320篇 |
2018年 | 856篇 |
2017年 | 877篇 |
2016年 | 817篇 |
2015年 | 857篇 |
2014年 | 1034篇 |
2013年 | 1097篇 |
2012年 | 664篇 |
2011年 | 673篇 |
2010年 | 727篇 |
2009年 | 824篇 |
2008年 | 503篇 |
2007年 | 393篇 |
2006年 | 383篇 |
2005年 | 322篇 |
2004年 | 235篇 |
2003年 | 210篇 |
2002年 | 206篇 |
2001年 | 233篇 |
2000年 | 126篇 |
1999年 | 215篇 |
1998年 | 270篇 |
1997年 | 262篇 |
1996年 | 325篇 |
1995年 | 228篇 |
1994年 | 227篇 |
1993年 | 179篇 |
1992年 | 147篇 |
1991年 | 134篇 |
1990年 | 93篇 |
1989年 | 104篇 |
1988年 | 81篇 |
1987年 | 93篇 |
1986年 | 83篇 |
1985年 | 52篇 |
1984年 | 47篇 |
1983年 | 38篇 |
1982年 | 42篇 |
1981年 | 25篇 |
1980年 | 31篇 |
1979年 | 23篇 |
1978年 | 19篇 |
1977年 | 14篇 |
1972年 | 10篇 |
1971年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 625 毫秒
91.
MA Nasar FRCP FRCP EM Lyle BSc MRPharmS 《International journal of clinical practice》1994,48(1):19-21
SUMMARY Serum potassium was measured within 24 hours in 156 patients (48 male, 108 female) with an average age of 81.9 years admitted to the unit with acute illness. Of the 156 patients, 88 (56.4%) were taking diuretics (none was on ACE inhibitors); 20 patients (12.8%) were also on digoxin therapy. In all, 24 patients (16%) had hypokalaemia and 3 (2%) hyperkalaemia. Hypokalaemia was seen in patients associated with acute illness. There was no significant difference between the diuretic and non-diuretic groups. Monitoring of serum potassium is not routinely indicated to detect hypokalaemia in patients on diuretic therapy except in those with severe hepatic or renal impairment or those on digoxin. 相似文献
92.
The adhesion to hydrogel contact lenses and growth of Serratia marcescens on artificial tear fluid (ATF) soaked lenses was investigated. Results indicated that a corneal ulcer isolate adhered more avidly to lenses; ATF increased adhesion for all strains tested. The contact lens induced acute red eye (CLARE) isolate adhered poorly; however; it grew to a larger extent on ATF-coated lenses. The ability of the corneal ulcer isolate to adhere to lenses may be an important factor in its pathogenicity whereas the ability of the CLARE isolate to grow on the lens in the presence of antimicrobial tear proteins may be important in the development of inflammation. 相似文献
93.
Danny Lam RMN RNT PGCE Dip in GHGMR BSc BA MSc MA & Linda Cheng RMN RGN RMNS RNT BA Dip in Counselling Supervision 《Journal of advanced nursing》1998,27(6):1143-1150
Research shows that clients with automatic thoughts (dysfunctional thinking) often do not think of alternative explanations in relation to negative events. Furthermore, these automatic thoughts are characterized by a broad global, self-evaluative and ambiguous nature that could make disputing (or changing the ways they think) the most difficult part of the therapeutic process. This paper proposes a two-stage practise-based disputing model, guided by research, that aims to 'bring' an automatic thought to a specific, objective, quantifiable and concrete level at which not only is the particular aspect(s) of the automatic thought that causes emotional disturbances finely focused, but the disputing is also likely to be effective and manageable. Furthermore, it will also generate alternative explanations that are helpful in reducing emotional disturbances and in facilitating problem solving approach. In this paper, the authors use a case example to discuss the rationale that underpins the conceptualization of the model and to illustrate the process in which the strategies of the model are effectively used. 相似文献
94.
Depth of epidural space in children 总被引:1,自引:0,他引:1
M. A. Hasan MB ChB DA FRCA R. F. Howard BSc MB ChB FRCA A. R. Lloyd-Thomas MB BS FRCA 《Anaesthesia》1994,49(12):1085-1087
95.
96.
97.
98.
This paper addresses some methodological issues related to the generation of knowledge for mental health practice. It is suggested that a knowledge and understanding of attitudes towards the mentally ill has the potential to inform policy and practice regarding the establishment of community mental health facilities in order to encourage their acceptance by the public. Traditional approaches to attitude research are outlined followed by the proposal of an alternative approach: discourse analysis. The utility of each approach is assessed with regard to the potential relevance and applicability of research findings to practice. Traditional approaches are criticized on the grounds that they fail to take into consideration the social contexts within which attitudes are naturally expressed. As a result, information which is of potential interest to mental health practitioners is lost and it is unclear how the findings of such research might relate to or be translated into practice. It is argued, that since this information is to be found in the language used to describe people with mental health problems and to express attitudes towards them, that discourse analysis is ideally suited to the study of attitudes towards the mentally ill. The potential utility of the approach is demonstrated by an empirical example. Implications for practice are considered. 相似文献
99.
Anin vitro electrophysiological study of the colon from patients with idiopathic chronic constipation 总被引:2,自引:0,他引:2
Charles H. V. Hoyle BSc PhD Michael A. Kamm MD John E. Lennard-Jones MD Geoffrey Burnstock PhD DSc 《Clinical autonomic research》1992,2(5):327-333
Preparations of the circular muscle layer from the sigmoid colon resected from patients with idiopathic chronic constipation were compared, at an electrophysiological level using the sucrose-gap technique, with preparations of the same region of the intestine resected from patients with rectal carcinoma. Non-adrenergic, non-cholinergic inhibitory neuromuscular transmission, represented by inhibitory junction potentials, was present in preparations from both groups. However, the inhibitory response in preparations from constipated patients had a slower or longer time-course than in those from cancer patients. Also, rebound activity following inhibitory transmission was observed in 34% of preparations from constipated patients but was observed in 67% of preparations from cancer patients. Preparations from both groups displayed the same patterns of spontaneous activity and the same proportion of each group was quiescent. The threshold for generation of action potentials and the passive resistance of the smooth muscle membrane were the same in both groups. However, quiescent preparations from constipated patients were less likely to discharge trains of action potentials when the smooth muscle membrane was depolarized than were preparations from cancer patients. These changes in transmission processes and excitability in tissue from constipated patients are discussed in relation to altered states of colonic motility found in people with idiopathic chronic constipation. 相似文献
100.
What Are the Etiology and Epidemiology of Out‐of‐hospital Pediatric Cardiopulmonary Arrest in Ontario,Canada? 总被引:1,自引:0,他引:1
Richard Bradley Gerein BSc MD Martin H. Osmond MDCM Ian G. Stiell MSc MD Lisa P. Nesbitt MHA Starla Burns BSc 《Academic emergency medicine》2006,13(6):653-658
Background: Pediatric cardiopulmonary arrest (CPA) outside of the hospital has a very high mortality rate. Objectives: To evaluate the etiology and initial compromise of pediatric CPA cases in hopes of developing strategies to improve out‐of‐hospital resuscitation. Methods: The Ontario Prehospital Advanced Life Support (OPALS) study was a large multicenter initiative to evaluate the impact of emergency medical services (EMS) programs on 17 communities with 40,000 critically ill and injured patients who were older than 11 years. As part of this study, the authors conducted a retrospective observational cohort study that included all children younger than 18 years of age with out‐of‐hospital CPA, during an 11‐year period from 1991–2002. CPA was defined as patient being pulseless, apneic, and requiring chest compressions. Data were collected from ambulance call reports and centralized dispatch data and were reviewed by two independent investigators. Results: There were 503 children with CPA in the sample. Mean age was 5.6 years (range, 0–17 yr); 58.4% of patients were male, and 37.8% were younger than 1 year of age. Cardiopulmonary resuscitation (CPR) first was started by a bystander in 32.4% of cases, whereas 66.0% were unwitnessed arrests. Initial rhythms were asystole 77.2% of the time, pulseless electrical activity 16.4% of the time, and ventricular fibrillation or ventricular tachycardia 4% of the time. Annual incidence was 9.1/100,000 children. CPA was witnessed in 34.0% of cases; 80.7% of these were bystander‐witnessed, and 18.1% were EMS‐witnessed. Primary pathogenic cause of arrest was medical in 61.2% of cases, trauma in 37.2% of cases, and indeterminate in 1.6% of cases. Initial underlying physiologic compromise of witnessed arrests was judged to be respiratory in 39.8% of cases, sudden collapse (presumed electrical) in 16.4% of cases, progressive shock in 1.2% of cases, and indeterminate in 42.6% of cases. Presumed etiology was trauma, 37.6%; sudden infant death syndrome (SIDS), 20.3%; and respiratory disease, 11.6%, most commonly. Survival to hospital discharge was 2.0%. Conclusions: This is one of the largest population‐based, prospective cohorts of pediatric CPA reported to date, and it reveals that most pediatric arrests are unwitnessed and receive no bystander CPR. Those that are witnessed most often are caused by respiratory arrests or trauma. Trauma, SIDS, and respiratory disease are the most common etiologies overall. These data are vital to planning large resuscitation trials looking at specific interventions (i.e., increasing bystander CPR) and highlight the need for better strategies for prevention and early recognition. 相似文献