全文获取类型
收费全文 | 980篇 |
免费 | 53篇 |
国内免费 | 46篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 45篇 |
妇产科学 | 12篇 |
基础医学 | 67篇 |
口腔科学 | 16篇 |
临床医学 | 105篇 |
内科学 | 196篇 |
皮肤病学 | 8篇 |
神经病学 | 61篇 |
特种医学 | 136篇 |
外科学 | 247篇 |
综合类 | 28篇 |
一般理论 | 4篇 |
预防医学 | 41篇 |
眼科学 | 11篇 |
药学 | 72篇 |
中国医学 | 1篇 |
肿瘤学 | 27篇 |
出版年
2019年 | 10篇 |
2018年 | 11篇 |
2017年 | 10篇 |
2014年 | 14篇 |
2013年 | 25篇 |
2012年 | 13篇 |
2011年 | 15篇 |
2010年 | 29篇 |
2009年 | 33篇 |
2008年 | 24篇 |
2007年 | 47篇 |
2006年 | 14篇 |
2005年 | 22篇 |
2004年 | 19篇 |
2003年 | 18篇 |
2002年 | 11篇 |
2000年 | 23篇 |
1999年 | 18篇 |
1998年 | 43篇 |
1997年 | 37篇 |
1996年 | 40篇 |
1995年 | 26篇 |
1994年 | 18篇 |
1993年 | 23篇 |
1992年 | 23篇 |
1991年 | 19篇 |
1990年 | 22篇 |
1989年 | 43篇 |
1988年 | 42篇 |
1987年 | 37篇 |
1986年 | 27篇 |
1985年 | 30篇 |
1984年 | 19篇 |
1983年 | 12篇 |
1982年 | 13篇 |
1981年 | 11篇 |
1980年 | 9篇 |
1979年 | 20篇 |
1978年 | 16篇 |
1977年 | 23篇 |
1976年 | 9篇 |
1975年 | 8篇 |
1974年 | 13篇 |
1973年 | 21篇 |
1972年 | 18篇 |
1971年 | 14篇 |
1970年 | 9篇 |
1969年 | 20篇 |
1968年 | 11篇 |
1967年 | 7篇 |
排序方式: 共有1079条查询结果,搜索用时 62 毫秒
1.
Scott A Fields Elizabeth Morrison Ernie Yoder Kevin Krane Thomas Agresta Rich Esham Frederick McCurdy Jonathan Rosen James Shumway 《Academic medicine》2002,77(6):543-546
PURPOSE: Chart notes are used to support billing codes under the evaluation and management guidelines of the Health Care Financing Administration (HCFA), in addition to serving as a record of the visit. To better understand the effect of the HCFA documentation guidelines, the authors collected data on how the guidelines affect participation by university- and community-based faculty in clinical education programs. METHOD: In 2000, the authors sent six copies of their questionnaire to the associate deans of the 125 U.S. medical schools and requested they distribute them to all core clerkship directors. The questionnaire consisted of multiple-choice and short-answer questions regarding documentation of medical visits, participation of community-based faculty, understanding of HCFA documentation guidelines, and effects on education programs. RESULTS: The response rate was about 50%. Most of the 379 clerkship directors who responded (77%) stated they were aware the HCFA documentation guidelines include specifications regarding the role medical students can play and documentation of medical visits, and 64% indicated they were concerned the guidelines would affect their educational programs. Concerns included the loss of student independence and active participation in the patient care environment (37), time constraints and the changing balance between education and service (16), loss of faculty and decreased morale (11), and decreased quality of care for patients (7). CONCLUSION: Leaders of medical education must work to modify these guidelines to protect the quality of patients' care, while maximizing students' educational opportunity and participation. 相似文献
2.
3.
We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder. 相似文献
4.
A L Harjula J C Baldwin N E Silverman N Blank P E Oyer E B Stinson N E Shumway 《The Journal of cardiovascular surgery》1990,31(1):1-6
Implantation response has been a critical problem following heart-lung and lung transplantation. While the precise etiology of this problem remains unclear, improvements in organ preservation would be expected to have a beneficial effect on implantation response. The time-related profile of the implantation response was studied in 20 patients who underwent heart-lung transplantation between March 1984-March 1987. In 10 operations the donors had intravenous prostaglandin E-1 pretreatment while 10 had no vasodilatation before explantation of the organs. Otherwise lung preservation and early (2 weeks) immunotherapy were similar in both groups. The implantation response was evaluated by chest films and postoperative lung functions and mechanics. Roentgenographic implantation response was evident from the first postoperative day, was less evident at the seventh postoperative day and then gradually increased during the second postoperative week. There was a tendency towards less implantation response in the PGE-1 group than in the control group, but no statistical difference was observed. Patients with severe operative bleeding problems were excluded from the study. Only peak inspiratory pressures were significantly higher in the control group than in the PGE-1 group (p less than 0.01). Other lung function studies (alveolar-capillary pO2 difference, extubation time) were not different in the groups. This study supported the hypothesis that prostaglandin E-1 may have salutary effects on graft preservation and implantation response in heart-lung transplantation. Since 1986, we have performed 16 heart-lung transplantations using graft preservation with PGE-1 and flush perfusion. Thirty-day mortality is 0% and 13 of 16 patients are surviving. 相似文献
5.
6.
Recurrent carotid stenosis. Incidence and management 总被引:1,自引:0,他引:1
The actual incidence of recurrent carotid occlusive disease is not known. From January 1974 through December 1984, fifty-four patients underwent at least one second carotid endarterectomy or reconstructive procedure at St. Thomas Hospital in Nashville. Five patients required a third carotid operation. This retrospective study examines case reports, risk factors, patient presentation, interval of recurrence, and pathology involved. Surgical techniques and results are described. Complications occurred in six patients undergoing a total of 66 operations for an overall incidence of 9 per cent. Thrombosis was minimized by the use of antiplatelet drugs. Follow-up of patients ranged from one to 84 months. Four main causes for restenosis are discussed. 相似文献
7.
PURPOSE: The purpose of this study was to examine the predictive validity of a collection of prelinguistic skills measured longitudinally in the 2nd year of life to language outcome in the 3rd year in children with typical language development. METHOD: A collection of prelinguistic skills was assessed in 160 children early (M = 14.31 months; SD = 1.36) and late (M = 19.76 months; SD = 1.16) in their 2nd year by using the Communication and Symbolic Behavior Scales Developmental Profile Behavior Sample (A. Wetherby & B. Prizant, 2002). The relation between the prelinguistic skills and the receptive and expressive language near the 3rd birthday was examined. RESULTS: Significant correlations were observed between many prelinguistic skills and language outcome. Regression analyses indicated that comprehension both early and late contributed unique variance to receptive and expressive language outcome. In addition, early in the 2nd year, inventory of conventional gestures contributed uniquely to receptive language outcome, and acts for joint attention contributed uniquely to expressive outcome. Late in the 2nd year, inventory of consonants contributed uniquely to expressive outcome. CONCLUSIONS: The findings demonstrate continuity between prelinguistic and linguistic skills and how individual differences in a number of prelinguistic skills contribute collectively and uniquely to language outcome in typically developing children. 相似文献
8.
Ensuring data quality in a multicenter clinical trial: remote site data entry, central coordination and feedback 总被引:1,自引:0,他引:1
J B Severe N R Schooler J H Lee G Haas K T Mueser P Rosen D Shortell M Shumway 《Psychopharmacology bulletin》1989,25(3):488-490
In an ongoing multicenter clinical trial, "Treatment Strategies in Schizophrenia," the five participating sites have the capacity to perform a variety of tasks or study functions independently. These tasks include (a) verification of diagnostic eligibility through the use of computerized decision algorithms; (b) assignment of patients to treatment based on prognostic indicators using a computerized randomization algorithm; (c) entry of data into a microcomputer using a clinical trial data management system that performs simple range and missing data item checks; and (d) regular transfer of all data to the central coordinating team. The clinical trial data management system employed allows for both independent site functioning and assurance of consistency across sites. The integration of a variety of software outside the main data management system provides the central coordinators with the tools to monitor critical data as it is collected, as well as the capacity to assess the flow, quality, and uniformity of the ongoing trial. 相似文献
9.
Linkage of the MHC to familial multiple sclerosis suggests genetic heterogeneity. The Multiple Sclerosis Genetics Group 总被引:5,自引:0,他引:5
Haines JL; Terwedow HA; Burgess K; Pericak-Vance MA; Rimmler JB; Martin ER; Oksenberg JR; Lincoln R; Zhang DY; Banatao DR; Gatto N; Goodkin DE; Hauser SL 《Human molecular genetics》1998,7(8):1229-1234
Multiple sclerosis (MS) is a demyelinating autoimmune disease of the
central nervous system. While its etiology is not well understood, genetic
factors are clearly involved. Until recently, most genetic studies in MS
have been association studies using the case-control design testing
specific candidate genes and studying only sporadic cases. The only
consistently replicated finding has been an association with the HLA-DR2
allele within the major histocompatibility complex (MHC) on chromosome 6.
Using the genetic linkage design, however, evidence for and against linkage
of the MHC to MS has been found, fostering suggestions that sporadic and
familial MS have different etiologies. Most recently, two of four genomic
screens demonstrated linkage to the MHC, although specific allelic
associations were not tested. Here, a dataset of 98 multiplex families was
studied to test for an association to the HLA-DR2 allele in familial MS and
to determine if genetic linkage to the MHC was due solely to such an
association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta)
in the MHC demonstrated strong genetic linkage (parametric lod scores of
4.60, 2.20 and 1.24, respectively) and a specific association with the
HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results
by HLA-DR2 status showed that the linkage results were limited to families
segregating HLA-DR2 alleles. These results demonstrate that genetic linkage
to the MHC can be explained by the HLA-DR2 allelic association. They also
indicate that sporadic and familial MS share a common genetic
susceptibility. In addition, preliminary calculations suggest that the MHC
explains between 17 and 62% of the genetic etiology of MS. This
heterogeneity is also supported by the minority of families showing no
linkage or association with loci within the MHC.
相似文献