收费全文 | 2142903篇 |
免费 | 165116篇 |
国内免费 | 3555篇 |
耳鼻咽喉 | 29122篇 |
儿科学 | 70617篇 |
妇产科学 | 59732篇 |
基础医学 | 313019篇 |
口腔科学 | 63098篇 |
临床医学 | 190103篇 |
内科学 | 413525篇 |
皮肤病学 | 46625篇 |
神经病学 | 167242篇 |
特种医学 | 84063篇 |
外国民族医学 | 534篇 |
外科学 | 323433篇 |
综合类 | 51067篇 |
现状与发展 | 4篇 |
一般理论 | 689篇 |
预防医学 | 163034篇 |
眼科学 | 49438篇 |
药学 | 162919篇 |
5篇 | |
中国医学 | 4860篇 |
肿瘤学 | 118445篇 |
2018年 | 20786篇 |
2016年 | 18098篇 |
2015年 | 20701篇 |
2014年 | 28351篇 |
2013年 | 43001篇 |
2012年 | 58231篇 |
2011年 | 61462篇 |
2010年 | 36313篇 |
2009年 | 34515篇 |
2008年 | 58411篇 |
2007年 | 61837篇 |
2006年 | 62992篇 |
2005年 | 60580篇 |
2004年 | 59654篇 |
2003年 | 56735篇 |
2002年 | 55640篇 |
2001年 | 101765篇 |
2000年 | 104906篇 |
1999年 | 88395篇 |
1998年 | 23721篇 |
1997年 | 21228篇 |
1996年 | 21359篇 |
1995年 | 20792篇 |
1994年 | 19467篇 |
1993年 | 18213篇 |
1992年 | 72234篇 |
1991年 | 70767篇 |
1990年 | 69101篇 |
1989年 | 67221篇 |
1988年 | 62285篇 |
1987年 | 61001篇 |
1986年 | 58129篇 |
1985年 | 55832篇 |
1984年 | 41614篇 |
1983年 | 35610篇 |
1982年 | 20599篇 |
1981年 | 18437篇 |
1980年 | 17311篇 |
1979年 | 39221篇 |
1978年 | 27318篇 |
1977年 | 23012篇 |
1976年 | 21892篇 |
1975年 | 23343篇 |
1974年 | 28258篇 |
1973年 | 27111篇 |
1972年 | 25053篇 |
1971年 | 23524篇 |
1970年 | 21899篇 |
1969年 | 20420篇 |
1968年 | 18727篇 |
Aims
Variations of the anatomy of donor hepatic arteries increase the number of arterial anastomoses during liver transplantation and, possibly, the incidence of hepatic artery thrombosis (HAT). In this study, we describe the arterial anatomic variations in liver grafts procured and transplanted by a single center in Greece, the techniques of arterial anastomosis, and their effect on the incidence of early HAT.Materials and Methods
From January 2013 to December 2017, the arterial anatomy of 116 grafts procured for liver transplantation were recorded, as well as the technique of arterial anastomosis and the incidence of early hepatic artery thrombosis (HAT <30 days).Results
A single hepatic artery was recorded in 72.41% of the procured grafts, an aberrant left hepatic artery (accessory or replaced) in 18 grafts (15.52%), and an aberrant right hepatic artery (accessory or replaced) in 17 grafts (14.66%), while other variations were observed in less than 1% of the procured livers. Of the 116 primary liver transplantations, 6 patients (5.17%) developed early HAT <30 days. Two of these patients (1.72%) had 1 anastomosis of the hepatic artery and 4 (3.45%) had 2 anastomoses due to anatomic variations.Conclusions
Anatomic variations of the hepatic artery in liver grafts is a common finding and increase the incidence of early HAT but not to a degree to make these grafts unusable. 相似文献Introduction
The fast track / ultra-fast-track protocols are techniques used to optimise the patient care process and a quick recovery after cardiac surgery. They are one of the mainstays of efficient practice. With their use, the length of hospital and intensive care unit (ICU) stays are reduced, with a direct impact on costs and the quality of the health service.Objective
To compare the length of stay in the ICU, length of hospital stay, and post-operative mortality in ultra-fast-track extubated (uFTE) patients and those with conventional extubation (CE) after cardiac surgery.Methods
Longitudinal, analytical, retrospective study was conducted, with the period between the time of surgery and discharge being included as the study period.Results
A total of 396 patients older than 18 years who required cardiac surgery were included, of whom 207 patients had (uFTE) and 189 had CE. Although the groups were not comparable due to the statistical differences found, when performing the multivariate adjustment, uFTE maintained its statistical independence and was associated with lower cardiovascular morbidity, such as myocardial ischaemia (95% CI: 0.37-0.86; P = .01) and lower post-surgical vasopressor requirement (95% CI: 0.18-0.49; P < .01). No significant differences were found in the length of hospital stay, ICU stay, or post-operative mortality in the ICU.Conclusion
Implementing the uFTE strategy, decreases cardiovascular morbidity and vasopressor requirement. The change to uFTE should be accompanied by changes in models and practices in patient recovery to standardised protocols. This study shows that uFTE did not reduce the length of ICU stay, hospital stay, or mortality. 相似文献Areas covered: the principal pharmacogenetic and non-genetic differences in the pharmacology of tamoxifen and endoxifen are evaluated. To this end, references from PubMed, Embase or Web of Science, among others, were reviewed As non-genetic factors, important differences and similarities such age, or adherence to tamoxifen therapy are comprehensively illustrated. Additionally, since CYP2D6 genotypes are considered the main limitation of tamoxifen, many studies have investigated the association between the worsened clinical outcomes in patients with non-functional CYP2D6 genotypes. In this review, an overview of the research on this field is presented. Also, a summary describing the literature about individualizing tamoxifen therapy with endoxifen concentrations and its limitations is listed.
Expert opinion: z-endoxifen hydrochloride is only investigated in the metastatic setting, still more research is required before its place in therapeutics is known. Similarly, monitoring tamoxifen efficacy based on endoxifen concentrations might not be overall recommended due to the limited evidence available. 相似文献
Background
Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.Methods
We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).Results
Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.Conclusions
Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation. 相似文献Methods: [11C]WAY100635, [18F]altanserin and positron emission tomography were used to compare 5-HT1A and 5-HT2A binding in MDD patients divided into eight past suicide attempters (>4yrs prior to scanning) and eight lifetime non-attempters, and both groups were compared to eight healthy volunteers.
Results: The two receptor types differed in binding pattern across brain regions from each other, but there were no differences in binding between healthy volunteers and the two depressed groups or between depressed suicide attempters and non-attempters. No effects of depression severity or lifetime aggression were observed for either receptor.
Conclusion: Limitations of this study include small sample size and absence of high lethality suicide attempts in the depressed attempter group. No trait-like binding correlations with past suicide attempt or current depression were observed. Given the heterogeneity of nonfatal suicidal behavior, a larger sample study emphasizing higher lethality suicide attempts may find the serotonin biological phenotype seen in suicide decedents. 相似文献