全文获取类型
收费全文 | 2701篇 |
免费 | 211篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 48篇 |
儿科学 | 57篇 |
妇产科学 | 30篇 |
基础医学 | 427篇 |
口腔科学 | 28篇 |
临床医学 | 239篇 |
内科学 | 479篇 |
皮肤病学 | 86篇 |
神经病学 | 347篇 |
特种医学 | 130篇 |
外科学 | 232篇 |
综合类 | 32篇 |
一般理论 | 2篇 |
预防医学 | 215篇 |
眼科学 | 52篇 |
药学 | 255篇 |
中国医学 | 8篇 |
肿瘤学 | 252篇 |
出版年
2024年 | 2篇 |
2023年 | 22篇 |
2022年 | 55篇 |
2021年 | 86篇 |
2020年 | 54篇 |
2019年 | 66篇 |
2018年 | 78篇 |
2017年 | 63篇 |
2016年 | 82篇 |
2015年 | 99篇 |
2014年 | 103篇 |
2013年 | 169篇 |
2012年 | 220篇 |
2011年 | 207篇 |
2010年 | 115篇 |
2009年 | 117篇 |
2008年 | 230篇 |
2007年 | 175篇 |
2006年 | 177篇 |
2005年 | 178篇 |
2004年 | 153篇 |
2003年 | 120篇 |
2002年 | 114篇 |
2001年 | 24篇 |
2000年 | 23篇 |
1999年 | 18篇 |
1998年 | 19篇 |
1997年 | 19篇 |
1996年 | 10篇 |
1995年 | 7篇 |
1994年 | 9篇 |
1993年 | 8篇 |
1992年 | 10篇 |
1991年 | 2篇 |
1990年 | 7篇 |
1989年 | 5篇 |
1988年 | 4篇 |
1987年 | 9篇 |
1986年 | 8篇 |
1985年 | 11篇 |
1984年 | 13篇 |
1983年 | 8篇 |
1982年 | 6篇 |
1981年 | 6篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 4篇 |
1977年 | 2篇 |
排序方式: 共有2919条查询结果,搜索用时 187 毫秒
1.
Ernst R. Kuse Joerg Kotzerke Silke Müller Björn Nashan Rainer Lück Karsten Jaeger 《Transplant international》2002,15(6):272-277
It has been demonstrated that total parenteral nutrition (TPN) modulates the function of the hepatic reticuloendothelial system (RES). The objective of this study was to evaluate the impact of two different TPN lipid emulsions on the recovery of allograft RES function after orthotopic liver transplantation (OLTx). In a prospective, double-blind study, OLTx patients were randomly assigned to two treatment groups. Group I ( n=13) received a TPN regimen that included long-chain triglycerides (LCT). Group II ( n=9) received a TPN regimen that included a fat emulsion consisting of both medium-chain triglycerides (MCT) and LCT. At baseline, i.e., on days 2 or 3 after OLTx ( t1), before lipids for TPN were started, hepatic RES function was determined using the human serum albumin millimicrosphere technique (K-value, 1/min). A second measurement ( t2) was obtained after 7 days of TPN, including one of the study's two fat emulsions. The mean (+/- SD) K-value (1/min) was 0.48+/-0.16 in the LCT group and 0.55+/-0.28 in the MCT/LCT group at t1, and it improved to 0.62+/-0.21 in the LCT group and to 0.86+/-0.32 in the MCT/LCT group at t2. RES function recovery was significantly better in the MCT/LCT group ( P< or = 0.05). MCT/LCT emulsion appears to be the TPN fat emulsion of choice after OLTx as it seems to have less impact on hepatic RES recovery. 相似文献
2.
Jenny Chang-Claude Silke Hermann Ursula Eilber Karen Steindorf 《Cancer epidemiology, biomarkers & prevention》2005,14(4):963-968
BACKGROUND: The long-term observation of vegetarians in affluent countries can provide insight into the relative effects of a vegetarian diet and lifestyle factors on mortality. METHODS: A cohort study of vegetarians and health-conscious persons in Germany was followed-up prospectively for 21 years, including 1,225 vegetarians and 679 health-conscious nonvegetarians. Standardized mortality ratios compared with the German general population were calculated for all causes and specific causes. Within the cohort, Poisson regression modeling was used to investigate the joint effects of several risk factors on overall and cause-specific mortality. RESULTS: Standardized mortality ratios for all-cause mortality was significantly below 100: 59 [95% confidence interval (95% CI), 54-64], predominantly due to a deficit of deaths from circulatory diseases. Within the cohort, vegetarian compared with nonvegetarian diet had no effect on overall mortality [rate ratio (RR), 1.10; 95% CI, 0.89-1.36], whereas moderate and high physical activity significantly reduced risk of death (RR, 0.62, 0.64), adjusted for age, sex, smoking, alcohol intake, body mass index, and educational level. Vegetarian diet was however associated with a reduced RR of 0.70 (95% CI, 0.41-1.18) for ischemic heart disease, which could partly be related to avoidance of meat. CONCLUSIONS: Both vegetarians and nonvegetarian health-conscious persons in this study have reduced mortality compared with the general population. Within the study, low prevalence of smoking and moderate or high level of physical activity but not strictly vegetarian diet was associated with reduced overall mortality. The nonsignificant reduction in mortality from ischemic heart diseases in vegetarians compared with health-conscious persons could be explained in part by avoidance of meat intake. 相似文献
3.
Dr. S. Besier T.M. Bingold F. Walcher K. Engels B. Spellerberg V. Brade C. Brandt 《Der Chirurg》2007,78(12):1148-1151
Streptococcus agalactiae, known as a pathogen that causes meningitis and septicemia in neonates, emerges as an invasive organism in nonpregnant adults. This case report describes the fulminant course of a necrotizing fasciitis (NF) with streptococcal toxic shock-like syndrome (STSS) in a 76-year-old diabetic patient caused by S. agalactiae, serotype V. Chronic diseases and immunodeficiency are considered to be risk factors for the acquisition of group B streptococcal disease. Since early surgical treatment in conjunction with antimicrobial and intensive care therapy is critical for the outcome of patients with NF and/or STSS, clinicians should be aware of invasive S. agalactiae infections in adults with subcutaneous emphysema. 相似文献
4.
Objective:
Evaluation of the periodontal health in patients during treatment with either fixed orthodontic appliances or the Invisalign® system. 相似文献5.
B. Silke J. P. Spiers S. Boyd E. Graham G. McParland M. E. Scott 《Clinical autonomic research》1994,4(1-2):49-56
The accuracy and precision of the Finapres in recording rest and exercise blood pressure compared with the intra-arterial (aortic and brachial) and random-zero sphygmomanometer methods was assessed in 84 ischaemic patients in three different studies. Firstly, comparison at rest with the aortic intraarterial pressure in 50 ischaemic patients demonstrated that the Finapres systolic (136.5 ± 21.1 vs. 129.3 ± 19.0 mmHg;p < 0.001) and mean (92.4 ± 13.4 vs. 90.7 ± 11.4 mmHg;p < 0.001) arterial pressures were higher and diastolic pressures lower (70.4 ± 11.5 vs. 71.5 ± 9.8 mmHg;p < 0.001). The reproducibility of the Finapres and invasive method was similar for systolic (4.6% vs. 4.0%), diastolic (2.8% vs. 2.7%) and mean (3.3% vs. 3.0%) blood pressures. Second, in seven subjects studied twice at rest and during 4 min supine bicycle exercise, the exercise increase in blood pressure was greater on the Finapres compared with the brachial intra-arterial pressure (systolic +10.2 ± 6.3 vs. +3.6 ± 9.8 mmHg; diastolic +9.6 ± 11.1 vs. +0.2 ± 2.1 mmHg;p = 0.02 for each); however, at steady-state the peak/trough differences in pressure between the methods were similar. Thirdly, compared under rest conditions, to random zero sphygmomanometer (RZO), the Finapres systolic pressure was higher (6.8 ± 3.5 mmHg) and diastolic pressure lower (–6.0 ± 1.9 mmHg). During upright bicycle exercise, the difference between the Finapres and RZO in systolic blood pressure increased at each level of exercise (+14.3 ± 4.2, +17.9 ± 4.0 and +22.2 ± 4.1 mmHg respectively at each exercise stage:p < 0.01). For RZO, diastolic blood pressure fell as exercise workload increased whereas Finapres diastolic blood pressure increased on exercise (3.1 ± 2.6, 7.0 ± 2.1 and 8.1 ± 2.0 mmHg respectively:p < 0.01). Thus there were systematic differences between the values recorded by the Finapres and proximal blood pressure methods and limited agreement in the rest to exercise increments related to light exercise. Calibration of the Finapres values in terms of the other methods is limited by the variable relationship to these related changes in arterial distensibility. 相似文献
6.
U Nowak-G?ttl E Besier W D Kreuz R Linde M Koert H K Breddin B Kornhuber 《Klinische P?diatrie》1992,204(1):37-42
In order to establish an univariate nonparametric pediatric tolerance region platelet function has been investigated in 105 healthy children and adolescents. In comparison to adult normal values, the bleeding time is shortened, spontaneous platelet aggregation is enhanced as well as collagen-induced platelet aggregation. 30% of the children showed an increased disaggregation in ADP-induced aggregation. A slight delay was found in the spreading of thrombocytes. Platelet volume shifted to the left. Values of beta-thromboglobulin were raised. Compared to adult values no alterations could be found in platelet shape-change. Changes of platelet functions were more apparent in the younger children. 相似文献
7.
Characterization of a functional promoter polymorphism of the human tryptophan hydroxylase 2 gene in serotonergic raphe neurons. 总被引:2,自引:0,他引:2
8.
U Nowak-G?ttl W D Kreuz E Besier H P Grüttner B Krackhardt H K Breddin B Kornhuber 《Monatsschrift für Kinderheilkunde》1991,139(12):821-825
Platelet count, spontaneous platelet aggregation, ADP- and collagen-induced platelet aggregation platelet adhesion, platelet volume, shape change, beta-thromboglobulin and von-Willebrand-factor have been investigated in 51 insulin dependent diabetic children without clinical signs of diabetic angiopathy. Compared to an age matched healthy control group diabetic children showed a significant enhancement of spontaneous platelet aggregation, elevated plasma levels of von-Willebrand-factor, increased platelet shape change and adhesion. No alterations could be found in ADP--and collagen--induced platelet aggregation and in beta-thromboglobulin levels. Significant correlations could be found between the total glycosylated haemoglobin concentrations (Hb A1) and spontaneous platelet aggregation, as well as between duration of diabetes Hb A1, and platelet volume. In this study we could demonstrate changes in platelet function in diabetic children without clinical signs of diabetic angiopathy. However these changes could be due to metabolic adjustment and may precede diabetic vasculopathy. 相似文献
9.
Karl‐Jürgen Br Stanislaw Brehm Michael Karl Boettger Gerd Wagner Silke Boettger Heinrich Sauer 《European Journal of Pain》2006,10(5):467-471
An altered perception of pain has been described for several psychiatric disorders. To date the influence of adjustment disorders (AD) on pain perception has not been described. Here, we investigated perception of experimentally induced pain in 15 patients suffering from AD (subtype with depressive symptoms) and controls matched for age and sex. Thresholds and tolerances were assessed for thermal and electrical pain on both sides of the body. We found an overall increase of pain thresholds and tolerances in AD patients as compared to controls, predominately on the right side of the body. Analogue findings have been reported for pain perception in major depressive disorder (MDD). Of the data obtained, only thermal pain threshold on the right arm correlated with the severity of depressive symptoms. Although the underlying pathology is elusive it is likely that the mechanisms for reduced pain sensitivity are comparable in MDD and AD. 相似文献
10.