全文获取类型
收费全文 | 5049篇 |
免费 | 283篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 34篇 |
儿科学 | 160篇 |
妇产科学 | 71篇 |
基础医学 | 590篇 |
口腔科学 | 228篇 |
临床医学 | 390篇 |
内科学 | 1232篇 |
皮肤病学 | 62篇 |
神经病学 | 488篇 |
特种医学 | 128篇 |
外科学 | 709篇 |
综合类 | 39篇 |
一般理论 | 1篇 |
预防医学 | 401篇 |
眼科学 | 68篇 |
药学 | 293篇 |
中国医学 | 58篇 |
肿瘤学 | 404篇 |
出版年
2023年 | 22篇 |
2022年 | 56篇 |
2021年 | 134篇 |
2020年 | 92篇 |
2019年 | 154篇 |
2018年 | 158篇 |
2017年 | 93篇 |
2016年 | 75篇 |
2015年 | 128篇 |
2014年 | 181篇 |
2013年 | 203篇 |
2012年 | 373篇 |
2011年 | 398篇 |
2010年 | 192篇 |
2009年 | 188篇 |
2008年 | 337篇 |
2007年 | 338篇 |
2006年 | 341篇 |
2005年 | 338篇 |
2004年 | 283篇 |
2003年 | 251篇 |
2002年 | 242篇 |
2001年 | 67篇 |
2000年 | 82篇 |
1999年 | 71篇 |
1998年 | 34篇 |
1997年 | 26篇 |
1996年 | 27篇 |
1995年 | 36篇 |
1994年 | 26篇 |
1993年 | 27篇 |
1992年 | 49篇 |
1991年 | 40篇 |
1990年 | 26篇 |
1989年 | 16篇 |
1988年 | 25篇 |
1987年 | 21篇 |
1986年 | 15篇 |
1985年 | 19篇 |
1984年 | 10篇 |
1983年 | 16篇 |
1981年 | 15篇 |
1980年 | 9篇 |
1976年 | 8篇 |
1975年 | 8篇 |
1973年 | 8篇 |
1972年 | 12篇 |
1971年 | 11篇 |
1970年 | 9篇 |
1968年 | 8篇 |
排序方式: 共有5356条查询结果,搜索用时 15 毫秒
91.
92.
Katherine C. Schinka Manfred H.M. van Dulmen Andrea D. Mata Robert Bossarte Monica Swahn 《Journal of adolescence》2013,36(6):1251-1260
Using latent class growth analysis, we were interested in investigating how experiences of loneliness emerge in distinct developmental patterns over the course of middle childhood and adolescence (NICHD Study of Early Child Care, N = 832). Second, we examined the role of demographic, mental health, and behavioral variables in association with these discrete patterns of loneliness. Loneliness was measured at 3 time points: age 9, age 11, and age 15. Results indicated five discrete trajectories of loneliness from middle childhood to adolescence. Most children exhibited a stable and low level of loneliness over time. The remaining children were split among moderate increasing, high increasing, decreasing, and chronic loneliness groups. Ethnicity, income, age 7 social skills, age 7 depression, and age 7 aggression were associated with trajectory membership. In addition, the loneliness trajectories predicted self-reports of social skills deficits, depression, aggression, and suicidal ideation at age 15. 相似文献
93.
94.
95.
96.
Biopsy‐proven acute cellular rejection as an efficacy endpoint of randomized trials in liver transplantation: a systematic review and critical appraisal 下载免费PDF全文
Manuel Rodríguez‐Perálvarez Jose M. Rico‐Juri Emmanuel Tsochatzis Patrizia Burra Manuel De la Mata Jan Lerut 《Transplant international》2016,29(9):961-973
Biopsy‐proven acute cellular rejection (ACR) is the primary efficacy endpoint in most randomized trials evaluating immunosuppression in liver transplantation. However, ACR is not a major cause of graft loss, and a certain grade of immune activation may be even beneficial for long‐term graft acceptance. Validated criteria to select candidates for liver biopsy are lacking, and routine clinical practice relies on liver tests, which are inaccurate markers of ACR. Indeed, both the agreement among clinicians to select candidates for liver biopsy and the correlation between the clinical suspicion of ACR and histological findings are poor. In randomized trials evaluating immunosuppression protocols, this concern grows exponentially due to the open‐label and multicenter nature of most studies. Therefore, biopsy‐proven ACR is a suboptimal efficacy endpoint given its limited impact on prognosis and the heterogeneous diagnosis, which may increase the risk of bias. Chronic rejection and/or graft loss would be more appropriate endpoints, but would certainly require larger studies with prolonged surveillances. An objective method to select candidates for liver biopsy is therefore urgently needed, and only severe episodes of histological ACR should be considered as potentially harmful. Emerging surrogate markers of ACR and antibody‐mediated rejection require further investigation to determine their clinical role. 相似文献
97.
Carlos Morales-Uribe Ana Ramírez Tatiana Suarez-Poveda Margarita Ortiz Alvaro Sanabria 《Emergency radiology》2016,23(5):421-431
This study was conducted in order to define the diagnostic performance of CT angiography for vascular injuries compared with angiography in patients with neck trauma. CT angiography is the cornerstone of diagnosis for hemodynamically stable patients with wounds suspicious of vascular trauma in the limbs, chest, or abdomen. Available evidence for the use of CT angiography in neck vascular trauma comes from small case series and few randomized controlled trials, and high-quality information does not exist regarding its performance. A protocol using the recommendations of the Cochrane Collaboration was designed. A systematic search of diagnostic studies without limits on language or time was carried out to December 2014. Studies including patients with neck trauma with retrospective or prospective data collection that assessed CT angiography compared with other methods were selected. Methodological quality was assessed using the QUADAS-2 tool. A hierarchical model ROC curve and a bivariate random effects model were used for the pooled analysis. Sixteen studies were selected and reviewed, and nine studies with 693 patients were included in this review. The overall sensitivity was 97 % (95 % CI 0.77–1.00; I 2?=?65.7 % (41.4–90.0)), while the overall specificity was 99 % (95 % CI 0.93–1.00; I 2?=?0). The hierarchic ROC curve showed an area under the curve of 0.99. Publication bias was not identified in this study. CT angiography can be stated as the gold standard for diagnosing vascular injuries in hemodynamically stable patients with neck trauma. 相似文献
98.
William N. Evans Ruben J. Acherman Michael L. Ciccolo Sergio A. Carrillo Alvaro Galindo Abraham Rothman Brody J. Winn Noel S. Yumiaco Humberto Restrepo 《Pediatric cardiology》2016,37(7):1274-1277
We tested the hypothesis that MELD-XI values correlated with hepatic total fibrosis scores obtained in 70 predominately stable, post-Fontan patients that underwent elective cardiac catheterization. We found a statistically significant correlation between MELD-XI values and total fibrosis scores (p = 0.003). Thus, serial MELD-XI values may be an additional useful clinical parameter for follow-up care in post-Fontan patients. 相似文献
99.
Long‐term results of a prospective randomized trial assessing the impact of re‐adaptation of the dorsolateral peritoneal layer after extended pelvic lymph node dissection and cystectomy 下载免费PDF全文
100.
Cappelletti M Barth H Fregni F Spelke ES Pascual-Leone A 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,179(4):631-642
It has been widely argued that the intraparietal sulcus (IPS) is involved in tasks that evoke representations of numerical
magnitude, among other cognitive functions. However, the causal role of this parietal region in processing symbolic and non-symbolic
numerosity has not been established. The current study used repetitive Transcranial Magnetic Stimulation (rTMS) to the left
and right IPS to investigate the effects of temporary deactivations of these regions on the capacity to represent symbolic
(Arabic numbers) and non-symbolic (arrays of dots) numerosities. We found that comparisons of both symbolic and non-symbolic
numerosities were impaired after rTMS to the left IPS but enhanced by rTMS to the right IPS. A signature effect of numerical
distance was also found: greater impairment (or lesser facilitation) when comparing numerosities of similar magnitude. The
reverse pattern of impairment and enhancement was found in a control task that required judging an analogue stimulus property
(ellipse orientation) but no numerosity judgements. No rTMS effects for the numerosity tasks were found when stimulating an
area adjacent but distinct from the IPS, the left and right angular gyrus. These data suggest that left IPS is critical for
processing symbolic and non-symbolic numerosity; this processing may thus depend on common neural mechanisms, which are distinct
from mechanisms supporting the processing of analogue stimulus properties.
H. Barth and F. Fregni contributed equally to this study. 相似文献