全文获取类型
收费全文 | 22845篇 |
免费 | 2071篇 |
国内免费 | 66篇 |
专业分类
耳鼻咽喉 | 246篇 |
儿科学 | 742篇 |
妇产科学 | 518篇 |
基础医学 | 3128篇 |
口腔科学 | 377篇 |
临床医学 | 2546篇 |
内科学 | 4776篇 |
皮肤病学 | 221篇 |
神经病学 | 1920篇 |
特种医学 | 945篇 |
外科学 | 3631篇 |
综合类 | 394篇 |
一般理论 | 25篇 |
预防医学 | 2111篇 |
眼科学 | 492篇 |
药学 | 1553篇 |
1篇 | |
中国医学 | 20篇 |
肿瘤学 | 1336篇 |
出版年
2022年 | 135篇 |
2021年 | 401篇 |
2020年 | 265篇 |
2019年 | 408篇 |
2018年 | 518篇 |
2017年 | 364篇 |
2016年 | 387篇 |
2015年 | 451篇 |
2014年 | 658篇 |
2013年 | 875篇 |
2012年 | 1456篇 |
2011年 | 1459篇 |
2010年 | 809篇 |
2009年 | 702篇 |
2008年 | 1276篇 |
2007年 | 1338篇 |
2006年 | 1355篇 |
2005年 | 1318篇 |
2004年 | 1270篇 |
2003年 | 1184篇 |
2002年 | 1154篇 |
2001年 | 453篇 |
2000年 | 445篇 |
1999年 | 394篇 |
1998年 | 269篇 |
1997年 | 260篇 |
1996年 | 228篇 |
1995年 | 186篇 |
1994年 | 180篇 |
1993年 | 198篇 |
1992年 | 285篇 |
1991年 | 282篇 |
1990年 | 252篇 |
1989年 | 248篇 |
1988年 | 233篇 |
1987年 | 216篇 |
1986年 | 219篇 |
1985年 | 197篇 |
1984年 | 173篇 |
1983年 | 181篇 |
1982年 | 139篇 |
1981年 | 160篇 |
1980年 | 127篇 |
1979年 | 183篇 |
1978年 | 152篇 |
1977年 | 116篇 |
1975年 | 117篇 |
1974年 | 116篇 |
1973年 | 135篇 |
1972年 | 117篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
Stuart J. Dilley Tracey J. Weiland Robert O’Brien Neil J. Cunningham Julian E. Van Dijk Rosie M. Mahoney 《Teaching and learning in medicine》2015,27(1):71-79
Theory: Immersive simulation is a common mode of education for medical students. Observation of clinical simulations prior to participation is believed to be beneficial, though this is often a passive process. Active observation may be more beneficial. Hypotheses: The hypothesis tested in this study was that the active use of a simple checklist during observation of an immersive simulation would result in better participant performance in a subsequent scenario compared with passive observation alone. Methods: Medical students were randomized to either passive or active (with checklist) observation of an immersive simulation involving cardiac arrest prior to participating in their own simulation. Performance measures included time to cardiopulmonary resuscitation (CPR) and time to defibrillation and were compared between first and second scenarios as well as between passive and active observers. Results: Seventy-nine simulations involving 232 students were conducted. Mean time to CPR was 18 seconds (SD = 11.6) for those using the checklist and 24 seconds (SD = 15.8) for those who observed passively (M difference = 6 seconds), t(35) = 1.46, p =.153. Time to defibrillation was 94 seconds (SD = 26.4) for those using the checklist and 92 seconds (SD = 23.8) for those who observed passively (M difference = –2 seconds), t(38) =.21, p =.837. Time to CPR was 24 seconds (SD = 15.8) for passive observers and 31 seconds (SD = 21.0; M difference = 7 seconds), t(35) = 1.13, p =.265, for their first scenario counterparts. Time to CPR was 18 seconds (SD = 11.6) for active observers and 36 seconds (SD = 26.2; M difference = 18 seconds), t(24) = 2.81, p =.010, for their first scenario counterparts. Time to defibrillation was 92 seconds (SD = 23.8) for passive observers and 125 seconds (SD = 32.2; M difference = 33 seconds), t(33) = 3.63, p =.001, for their first scenario counterparts. Time to defibrillation was 94 seconds (SD = 26.4) for the active observers and 132 seconds (SD = 52.9; M difference = 38 seconds), t(28) =.46, p =.008, for their first scenario counterparts. Conclusions: Observation alone leads to improved performance in the management of a simulated cardiac arrest. The active use of a simple skills-based checklist during observation did not appear to improve performance over passive observation alone. 相似文献
4.
Aurora Perez-Cornago Georgina K. Fensom Colm Andrews Eleanor L. Watts Naomi E. Allen Richard M. Martin Mieke Van Hemelrijck Timothy J. Key Ruth C. Travis 《British journal of cancer》2020,123(12):1808
Background Although prostate cancer is a leading cause of cancer death, its aetiology is not well understood. We aimed to identify novel biochemical factors for prostate cancer incidence and mortality in UK Biobank.Methods A range of cardiovascular, bone, joint, diabetes, renal and liver-related biomarkers were measured in baseline blood samples collected from up to 211,754 men at recruitment and in a subsample 5 years later. Participants were followed-up via linkage to health administrative datasets to identify prostate cancer cases. Hazard ratios (HRs) and 95% confidence intervals were calculated using multivariable-adjusted Cox regression corrected for regression dilution bias. Multiple testing was accounted for by using a false discovery rate controlling procedure.Results After an average follow-up of 6.9 years, 5763 prostate cancer cases and 331 prostate cancer deaths were ascertained. Prostate cancer incidence was positively associated with circulating vitamin D, urea and phosphate concentrations and inversely associated with glucose, total protein and aspartate aminotransferase. Phosphate and cystatin-C were the only biomarkers positively and inversely, respectively, associated with risk in analyses excluding the first 4 years of follow-up. There was little evidence of associations with prostate cancer death.Conclusion We found novel associations of several biomarkers with prostate cancer incidence. Future research will examine associations by tumour characteristics.Subject terms: Predictive markers, Prostate cancer, Risk factors 相似文献
5.
6.
Costas D Lallas Erik P Castle Richard T Schlinkert Paul E Andrews 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2006,10(2):135-140
BACKGROUND AND OBJECTIVES: In 1999, our institution began a kidney transplant program with collaboration between the departments of General Surgery/Transplantation and Urology. From the onset, donor nephrectomies were performed laparoscopically and are currently the domain of Urology, which had no prior laparoscopic experience before this undertaking. We reviewed our experience. METHODS: A database of our experience was kept prospectively from June 1999 to November 2004. Records of both donors and recipients were reviewed. Special attention was directed toward our changes in technique and their relationship to outcomes, with emphasis on graft extraction and overall complication rates. RESULTS: We reviewed the records of 205 consecutive procedures. We report excellent donor outcomes, including mean operative time (112 minutes), estimated blood loss (120 mL), and length of stay (2.3 days). Complication (14.1%) and open conversion (1.5%) rates were low. For the recipients, early (98.0%) and 1-year (94.7%) graft survival, and ureteral ischemia (2.4%) rates were also appropriate with contemporary experience. CONCLUSIONS: We report our results on laparoscopic donor nephrectomy in a de novo renal transplant program. Because of this experience, we have ventured into other horizons of urologic laparoscopy and currently produce enough volume to support a laparoscopic fellowship. We feel that a productive donor nephrectomy program can enhance urologic laparoscopic programs and should be taken advantage of when available. 相似文献
7.
Outcomes at 3 years of a prospective pilot study of Campath-1H and sirolimus immunosuppression for renal transplantation 总被引:2,自引:0,他引:2
Rolf N. Barth Christina A. Janus Christine A. Lillesand Nancy A. Radke John D. Pirsch Bryan N. Becker Luis A. Fernandez L. Thomas Chin Yolanda T. Becker Jon S. Odorico Anthony M. D''Alessandro Hans W. Sollinger Stuart J. Knechtle 《Transplant international》2006,19(11):885-892
Campath-1H (alemtuzumab) induction was used for renal transplantation in combination with sirolimus as immunosuppression. We previously reported a high (28%) rate of early rejection with this regimen, and now report 3-year outcomes. Twenty-nine patients were recipients of either deceased donor or non-HLA (Human Leukocyte Antigen) identical living donor primary renal allografts. Clinical parameters including infection, malignancy, kidney function, and kidney histology were followed prospectively for 3 years. Three-year cumulative graft and patient survival were 96% and 100%, respectively. Twenty patients were maintained on steroid-free immunosuppressive regimens, and 15 patients were maintained on monotherapy for immunosuppression (12 on sirolimus). No serious infectious complications were observed and two patients developed basal cell skin cancer. The 3-year results of our initial pilot study demonstrate good graft (96%) and patient (100%) outcomes. Campath-1H induction has yielded a high proportion of patients maintained on immunosuppressive monotherapy (57%) without serious infectious- and no malignancy-related complications. The reported regimen yielded novel insights into both Campath-1H and sirolimus therapy in renal transplantation. Because of the higher incidence of early rejection, we recommend a modified strategy of immunosuppression including a brief course of a calcineurin inhibitor. 相似文献
8.
Relationships Between Arousal-Related Moods and Episodic Tension-Type Headache: A Biopsychological Study 总被引:3,自引:0,他引:3
An exploratory study was conducted examining arousal-related moods and episodic tension-type headache. Twelve subjects meeting International Headache Society criteria for episodic tension-type headache and 12 headache-free controls recorded headache activity and mood eight times daily for 14 consecutive days. Moods were measured using the Activation-Deactivation Adjective Check List, a self-report list that subjectively represents general arousal along two dimensions of Tension and Energy. Headache subjects had higher Tension levels than controls even in the absence of pain, and greater variation in this dimension as well. Within the headache group, Tension during pain-free periods was significantly lower than when experiencing headache, and was correlated with headache activity. The results were taken to support Thayer's (1989) biopsychological model of mood and arousal, and are discussed in terms of the model's heuristic value for general arousal and headache research. 相似文献
9.
Veena Kumari Jeffrey A. Gray Philip J. Corr Owen F. Mulligan Paul A. Cotter Stuart A. Checkley 《Psychopharmacology》1997,129(3):271-276
The effects of an indirect dopamine-agonist, d-amphetamine, and a non-selective dopamine receptor antagonist, haloperidol, were investigated in normal male volunteers using
a between-subjects double-blind design in a procedural learning task, thought mainly to involve unconscious/automatic learning.
The results showed: (1) d-amphetamine facilitated response speed, whereas haloperidol inhibited it, in comparison to placebo; (2) the linear increase
in procedural learning corresponded with pharmacological manipulation of degree of dopaminergic activity, i.e. subjects given
haloperidol showed the least, and subjects given d-amphetamine the greatest, procedural learning. The implications of these findings are discussed in relation to investigation
of abnormalities of procedural learning processes in schizophrenia.
Received: 28 June 1996/Final version: 2 October 1996 相似文献
10.
Background: The bariatric patient exists in dynamic relationship with family members and friends who have considerable influence
upon the patient and his or her surgical outcome. When family members and friends behave as intimate saboteurs, they attempt
to hamper, hurt, or subvert the bariatric patient's goal of achieving and maintaining a healthy body weight. Successful or
not, intimate saboteurs provide significant treatment challenges for the patient and the treatment team. Methods and Patients:
Patient profiles provide examples of intimate sabotage. The psychological construct of Family Systems Theory is used as a
plausible explanation for the sabotage of friends and family. Conclusions: Multidisciplinary professionals treating the bariatric
patient must be aware of the critical influence of intimate saboteurs and the tactics they use to sabotage. Treatment guidelines
recommended by Family Systems Theory are presented as strategies to mitigate the influence of intimate saboteurs. 相似文献