全文获取类型
收费全文 | 3208篇 |
免费 | 291篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 19篇 |
儿科学 | 86篇 |
妇产科学 | 40篇 |
基础医学 | 484篇 |
口腔科学 | 47篇 |
临床医学 | 422篇 |
内科学 | 653篇 |
皮肤病学 | 68篇 |
神经病学 | 287篇 |
特种医学 | 71篇 |
外科学 | 475篇 |
综合类 | 60篇 |
一般理论 | 4篇 |
预防医学 | 228篇 |
眼科学 | 68篇 |
药学 | 259篇 |
中国医学 | 19篇 |
肿瘤学 | 217篇 |
出版年
2023年 | 25篇 |
2022年 | 42篇 |
2021年 | 67篇 |
2020年 | 45篇 |
2019年 | 58篇 |
2018年 | 85篇 |
2017年 | 67篇 |
2016年 | 78篇 |
2015年 | 80篇 |
2014年 | 112篇 |
2013年 | 132篇 |
2012年 | 183篇 |
2011年 | 229篇 |
2010年 | 141篇 |
2009年 | 105篇 |
2008年 | 184篇 |
2007年 | 214篇 |
2006年 | 163篇 |
2005年 | 197篇 |
2004年 | 169篇 |
2003年 | 184篇 |
2002年 | 149篇 |
2001年 | 71篇 |
2000年 | 66篇 |
1999年 | 62篇 |
1998年 | 39篇 |
1997年 | 27篇 |
1996年 | 25篇 |
1995年 | 30篇 |
1994年 | 22篇 |
1993年 | 16篇 |
1992年 | 42篇 |
1991年 | 35篇 |
1990年 | 26篇 |
1989年 | 35篇 |
1988年 | 43篇 |
1987年 | 31篇 |
1986年 | 19篇 |
1985年 | 28篇 |
1984年 | 14篇 |
1983年 | 15篇 |
1982年 | 15篇 |
1980年 | 9篇 |
1979年 | 14篇 |
1977年 | 11篇 |
1976年 | 10篇 |
1975年 | 10篇 |
1974年 | 8篇 |
1973年 | 8篇 |
1972年 | 11篇 |
排序方式: 共有3507条查询结果,搜索用时 15 毫秒
11.
12.
S M Magesa T J Wilkes A E Mnzava K J Njunwa J Myamba M D Kivuyo N Hill J D Lines C F Curtis 《Acta tropica》1991,49(2):97-108
The malaria vector population consisted mainly of Anopheles gambiae s.s. with a small contribution from An. funestus and An. rivulorum. The mosquitoes coming to bite in bedrooms were monitored with light traps set beside untreated bednets. When impregnated bednets were provided for all the other beds in a village the Anopheles populations declined but the Culex quinquefasciatus populations were unaffected. The survival of An. gambiae (as measured by the mean number of ovarian dilatations) and the sporozoite rate declined following introduction of the nets and the estimated sporozoite inoculation rates into people not under their nets declined by more than 90%. The net introductions caused sharp declines in the number of mosquitoes resting indoors, but the evidence was inconclusive regarding diversion to outdoor resting, animal biting, earlier biting or outdoor biting. DDT spraying greatly reduced the Anopheles populations. 相似文献
13.
K J Njunwa J D Lines S M Magesa A E Mnzava T J Wilkes M Alilio K Kivumbi C F Curtis 《Acta tropica》1991,49(2):87-96
In five Tanzanian villages, nets impregnated with permethrin or lambdacyhalothrin were given out. The people received them enthusiastically and brought their nets for re-impregnation at six monthly intervals. Bioassays showed that the insecticidal power of permethrin impregnated nets remained adequate for six months unless the nets were washed. Nets with 30 mg lambdacyhalothrin/m2 retained high insecticidal power despite washing, but this dose caused temporary cold-like symptoms in those sleeping under freshly treated dry nets. Methods by which durable bednets might be made affordable by Tanzanian villagers are discussed. 相似文献
14.
To determine if amplification of the C-erb-B2 proto-oncogene could be correlated with prognosis in carcinoid tumours, 49 pulmonary carcinoid tumours (26 typical, 23 atypical) were examined using a polyclonal antibody to the C-terminal peptide of the C-erb-B2 protein sequence. No C-erb-B2 gene product could be shown: the demonstration of C-erb-B2 does not seem to help, therefore, in determining diagnosis or prognosis in pulmonary carcinoid tumours. 相似文献
15.
A number of factors affecting the stability of propranolol HC1 during electrophoretic control were investigated. It was found that significant degradation of propranolol HC1 and hydrolysis of water occurred when a current of 15 mA was used with platinized electrodes. This degradation was thought to be due to decomposition of propranolol HC1 at the electrodes. Degradation could be significantly reduced by using uncoated platinum electrodes and currents in the range of 0 to 2.5 mA, while still allowing control of drug delivery rates. Electrode reaction processes were found at high ionic strengths and high drug concentrations but were not thought to be associated with drug decomposition. 相似文献
16.
17.
H C Wilkes T W Meade S Barzegar A J Foley L O Hughes K A Bauer R D Rosenberg G J Miller 《Thrombosis and haemostasis》1992,67(5):503-506
The effects of gemfibrozil on several indices of haemostatic activity were explored in male patients with coronary heart disease (CHD). Sixty-three of 71 patients completed a crossover study in which gemfibrozil 1,200 mg/day and matching placebo were each taken in randomised order for 2 months in a double-blind manner, separated by a 2-month washout period. Serum cholesterol decreased by an average (95% confidence interval) of 12 (9 to 15)% and non-fasting triglyceride concentration by 43 (34 to 51)% during active treatment. Plasma prothrombin fragment F1 + 2 concentration, a marker of the in vivo rate of generation of thrombin, was 25 (12 to 37)% lower on average while on gemfibrozil than during the placebo phase. Factor VII coagulant activity (VIIc) and antigen concentration, and fibrinopeptide A concentration were not influenced by gemfibrozil in the group overall. However, the VIIc response appeared to be dependent upon the untreated cholesterol level. Hypercholesterolaemic men (cholesterol greater than 6.5 mmol/l) experienced a significant reduction in VIIc averaging 6% of standard during active therapy. Other effects of gemfibrozil were a 5 (2 to 9)% increase in plasma fibrinogen by a gravimetric method, an 11 (8 to 13)% increase in platelet count, and a 6 (2 to 10)% reduction in white cell count. The reduced incidence of CHD following gemfibrozil therapy in hyperlipidaemic patients may arise in part through a reduction in procoagulant activity and thus the risk of an occlusive coronary thrombosis. 相似文献
18.
19.
20.
Effect of peri-operative red blood cell transfusion on 30-day and 1-year mortality following coronary artery bypass surgery. 总被引:2,自引:0,他引:2
Manoj Kuduvalli Aung Y Oo Nick Newall Antony D Grayson Mark Jackson Michael J Desmond Brian M Fabri Abbas Rashid 《European journal of cardio-thoracic surgery》2005,27(4):592-598
OBJECTIVE: The purpose of this study was to examine the effect of peri-operative red blood cell (RBC) transfusion on 30-day and 1-year mortality following coronary artery bypass grafting (CABG). METHODS: We retrospectively analysed 3024 consecutive patients who underwent isolated CABG between January 1999 and December 2001. Patient records were linked to the National Strategic Tracing Service, which records all mortality in the UK. Thirty-day and 1-year mortality were derived from Kaplan-Meier curves. Confounding variables were controlled for by constructing a propensity score for the probability of receiving a transfusion from core patient characteristics including the lowest recorded laboratory haemoglobin (LL Hb) from a clinical chemistry database (C statistic 0.81). The propensity score and the comparison variable (transfusion versus no transfusion) were included in a Cox proportional hazards analysis, allowing calculation of adjusted hazard ratios (HR) and Kaplan-Meier survival curves. RESULTS: Nine hundred and forty (31.1%) patients received RBC transfusion during or within 72h of surgery. Predictors of the need for transfusion were LL Hb and lower body mass index, use of cardiopulmonary bypass, female sex, number of grafts, renal dysfunction, increased age, extent of disease, and prior CABG; these factors were all included in the propensity score. After 1-year of follow-up, 122 (4.03%) deaths occurred. The crude HR for 1-year mortality in patients transfused was 3.0 (P<0.001). After adjusting for the propensity score, re-operation for bleeding, peri-operative blood loss and post-operative complications, the adjusted 30-day mortality was 1.9% in transfused patients compared to 1.1% in patients not transfused (P<0.05). The adjusted HR for 1-year mortality in patients transfused was 1.88 (P<0.01). CONCLUSIONS: Peri-operative RBC transfusion after CABG is associated with an increased risk of mortality during a 1-year follow-up period, with a large proportion of deaths occurring within 30-days. 相似文献