全文获取类型
收费全文 | 5879篇 |
免费 | 458篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 66篇 |
儿科学 | 125篇 |
妇产科学 | 75篇 |
基础医学 | 842篇 |
口腔科学 | 105篇 |
临床医学 | 706篇 |
内科学 | 1070篇 |
皮肤病学 | 79篇 |
神经病学 | 651篇 |
特种医学 | 190篇 |
外科学 | 1168篇 |
综合类 | 70篇 |
一般理论 | 3篇 |
预防医学 | 427篇 |
眼科学 | 157篇 |
药学 | 339篇 |
中国医学 | 7篇 |
肿瘤学 | 275篇 |
出版年
2023年 | 54篇 |
2022年 | 90篇 |
2021年 | 187篇 |
2020年 | 103篇 |
2019年 | 218篇 |
2018年 | 250篇 |
2017年 | 183篇 |
2016年 | 162篇 |
2015年 | 153篇 |
2014年 | 278篇 |
2013年 | 343篇 |
2012年 | 519篇 |
2011年 | 506篇 |
2010年 | 264篇 |
2009年 | 213篇 |
2008年 | 382篇 |
2007年 | 381篇 |
2006年 | 338篇 |
2005年 | 344篇 |
2004年 | 277篇 |
2003年 | 215篇 |
2002年 | 240篇 |
2001年 | 46篇 |
2000年 | 38篇 |
1999年 | 51篇 |
1998年 | 50篇 |
1997年 | 31篇 |
1996年 | 41篇 |
1995年 | 34篇 |
1994年 | 29篇 |
1993年 | 27篇 |
1992年 | 37篇 |
1991年 | 21篇 |
1990年 | 17篇 |
1989年 | 24篇 |
1988年 | 26篇 |
1987年 | 17篇 |
1986年 | 18篇 |
1985年 | 18篇 |
1984年 | 10篇 |
1983年 | 14篇 |
1982年 | 7篇 |
1981年 | 13篇 |
1980年 | 6篇 |
1979年 | 6篇 |
1975年 | 7篇 |
1973年 | 5篇 |
1972年 | 5篇 |
1971年 | 5篇 |
1969年 | 5篇 |
排序方式: 共有6355条查询结果,搜索用时 15 毫秒
1.
2.
Hanna Lee Mary K. Tan Andrew T. Yan Paul Angaran Paul Dorian Claudia Bucci Jean C. Gregoire Alan D. Bell Martin S. Green Peter L. Gross Allan Skanes Charles R. Kerr L. Brent Mitchell Jafna L. Cox Vidal Essebag Brett Heilbron Krishnan Ramanathan Carl Fournier Shaun G. Goodman 《The Canadian journal of cardiology》2019,35(2):160-168
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3.
Davangere P Devanand Christian G Habeck Matthias H Tabert Nikolaos Scarmeas Gregory H Pelton James R Moeller Brett D Mensh Tyler Tarabula Ronald L Van Heertum Yaakov Stern 《Neuropsychopharmacology》2006,31(6):1327-1334
Temporoparietal and posterior cingulate metabolism deficits characterize patients with Alzheimer's disease (AD). A H(2)(15)O resting PET scan covariance pattern, derived by using multivariate techniques, was previously shown to discriminate 17 mild AD patients from 16 healthy controls. This AD covariance pattern revealed hypoperfusion in bilateral inferior parietal lobule and cingulate; and left middle frontal, inferior frontal, precentral, and supramarginal gyri. The AD pattern also revealed hyperperfusion in bilateral insula, lingual gyri, and cuneus; left fusiform and superior occipital gyri; and right parahippocampal gyrus and pulvinar. In an independent sample of 23 outpatients with mild cognitive impairment (MCI) followed at 6-month intervals, the AD pattern score was evaluated as a predictor of cognitive decline. In this MCI sample, an H2(15)O resting PET scan was carried out at baseline. Mean duration of follow-up was 48.8 (SD 15.5) months, during which time six of 23 MCI patients converted to AD. In generalized estimating equations (GEE) analyses, controlling for age, sex, education, and baseline neuropsychological scores, increased AD pattern score was associated with greater decline in each neuropsychological test score over time (Mini Mental State Exam, Selective Reminding Test delayed recall, Animal Naming, WAIS-R digit symbol; Ps<0.01-0.001). In summary, a resting PET covariance pattern previously reported to discriminate AD patients from control subjects was applied prospectively to an independent sample of MCI patients and found to predict cognitive decline. Independent replication in larger samples is needed before clinical application can be considered. 相似文献
4.
5.
Mahrdad Farahmand M.D. Brett C. Sheppard M.D. Clifford W. Deveney M.D. Karen E. Deveney M.D. Richard A. Crass M.D. 《Journal of gastrointestinal surgery》1997,1(2):182-187
Between 1989 and 1995 we performed completion gastrectomy for non-malignant disease in 21 patients (11 men and 10 women, mean
age 48.4 years). These patients had undergone a total of 48 prior gastric operations. Indications for completion gastrectomy
in this group were anastomotic ulceration with stricture in eight patients, alkaline reflux gastritis and/or esophagitis in
eight, postsurgical gastroparesis in two, gastroesophageal necrosis in two, and gastrocutaneous fistula in one. Major preoperative
symptoms included nausea and vomiting in 16 cases, abdominal pain in 15, dysphagia in 14, heartburn in seven, and weight loss
in five. Following completion gastrectomy, five patients (24%) had serious complications and there was one postoperative death
(5%). Five patients were lost to follow-up. For the remaining 15 patients, mean follow-up has been 30 months with a range
of 1 to 70 months. These patients were all interviewed and eight (53%) report significant improvement, two (13%) report moderate
improvement, and four (27%) report no improvement; one patient (7%) has had worsening of symptoms since undergoing completion
gastrectomy. The average body weight index was essentially unchanged after completion gastrectomy. We conclude that completion
gastrectomy with Roux-en-Y esophagojejunostomy results in a favorable outcome in the majority of selected patients with diseases
of the foregut who are unresponsive to less radical treatment.
Presented at the Thirty-Seventh Annual Meeting of The Society for Surgery of the Alimentary Tract, San Francisco, Calif.,
May 19–22, 1996. 相似文献
6.
Dissociative responses to trauma have been hypothesized to be associated with long-term increases in psychopathology. The purpose of this study was to examine dissociative responses to premilitary, combat-related and postmilitary traumatic events and long-term psychopathology in Vietnam combat veterans with (n = 34) and without (n = 28) posttraumatic stress disorder (PTSD). PTSD patients reported higher levels of dissociative states at the time of combat-related traumatic events than non-PTSD patients. Higher levels of dissociative states persisted in PTSD patients in the form of higher levels of dissociative states in response to postmilitary traumatic events. In addition, dissociative responses to combat trauma were associated with higher long-term general dissociative symptomatology as measured by scores on the Dissociative Experience Scale, as well as increases in the number of flashbacks since the time of the war. These findings are consistent with previous formulations that dissociation in the face of trauma is a marker of long-term psychopathology. 相似文献
7.
Brett Charlton Joseph Meltzer C. Garrison Fathman 《European journal of immunology》1994,24(7):1706-1709
Single-positive thymocytes are the immediate precursors of peripheral recent thymic emigrants (RTE) which develop into mature peripheral T cells. The functional ability of RTE is unclear but their state of differentiation may be relevant to the development of tolerance to peripheral “self” antigens. Since RTE are difficult to analyze, precursor CD4+/8− thymocytes were assessed in a model in vivo to determine their functional capability and their susceptibility to tolerance induction. The ability of both heat-stable antigen-positive (HSA+) (immature) and HSA− (mature) single-positive thymocytes to cause graft-versus-host disease (GVHD) across non-major histocompatibility complex differences was examined. Both HSA− and HSA+ CD4+/8− thymocytes from C3H mice caused lethal GVHD in AKR recipients as did CD4+ peripheral T cells in controls. Further, neonatal C3H thymocytes also caused lethal GVHD in AKR recipients. Since CD4+/8− thymocytes are the precursors of RTE, these results suggest that RTE are not susceptible to tolerance induction to “minor” antigens and may have a normal immune function in vivo. This would suggest that peripheral tolerance may be dependent upon the manner of antigen presentation rather than T cell maturity. 相似文献
8.
Although psychological debriefing (PD) represents the most common form of early intervention for recently traumatized people, there is little evidence supporting its continued use with individuals who experience severe trauma. This review identifies the core issues in early intervention that need to be addressed in resolving the debate over PD. It critiques the available evidence for PD and the early provision of cognitive-behavioral therapy (CBT). Based on available evidence, we propose that psychological first aid is an appropriate initial intervention, but that it does not serve a therapeutic or preventive function. When feasible, initial screening is required so that preventive interventions can be used for those individuals who may have difficulty recovering on their own. Evidence-based CBT approaches are indicated for people who are at risk of developing posttraumatic psychopathology. Guidelines for managing acutely traumatized people are suggested and standards are proposed to direct future research that may advance our understanding of the role of early intervention in facilitating adaptation to trauma. 相似文献
9.
The effect on microleakage of a modification of the cavosurface finish was evaluated using extracted thermalcycled teeth. Composite resin was placed in cavity preparations on root surfaces of teeth and finished to leave either a flash of material on the margin or finished flush to the margin. The teeth were thermalcycled for 10 days at 5 and 55 degrees C. The teeth were evaluated for microleakage using the silver nitrate staining procedure. Results showed a significant decrease in the amount of microleakage on the margins finished leaving a flash of composite resin. Clinical trials placing these restorations on root surfaces will be necessary to evaluate the impact on the periodontal health. 相似文献
10.