全文获取类型
收费全文 | 1398篇 |
免费 | 77篇 |
国内免费 | 29篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 33篇 |
妇产科学 | 27篇 |
基础医学 | 161篇 |
口腔科学 | 46篇 |
临床医学 | 141篇 |
内科学 | 263篇 |
皮肤病学 | 18篇 |
神经病学 | 41篇 |
特种医学 | 261篇 |
外科学 | 111篇 |
综合类 | 129篇 |
预防医学 | 43篇 |
眼科学 | 24篇 |
药学 | 87篇 |
1篇 | |
中国医学 | 12篇 |
肿瘤学 | 101篇 |
出版年
2023年 | 16篇 |
2022年 | 8篇 |
2021年 | 29篇 |
2020年 | 34篇 |
2019年 | 31篇 |
2018年 | 38篇 |
2017年 | 33篇 |
2016年 | 29篇 |
2015年 | 33篇 |
2014年 | 48篇 |
2013年 | 80篇 |
2012年 | 70篇 |
2011年 | 79篇 |
2010年 | 47篇 |
2009年 | 60篇 |
2008年 | 71篇 |
2007年 | 62篇 |
2006年 | 44篇 |
2005年 | 44篇 |
2004年 | 44篇 |
2003年 | 31篇 |
2002年 | 25篇 |
2001年 | 29篇 |
2000年 | 31篇 |
1999年 | 36篇 |
1998年 | 47篇 |
1997年 | 39篇 |
1996年 | 43篇 |
1995年 | 27篇 |
1994年 | 23篇 |
1993年 | 24篇 |
1992年 | 12篇 |
1991年 | 9篇 |
1990年 | 9篇 |
1989年 | 24篇 |
1988年 | 27篇 |
1987年 | 18篇 |
1986年 | 23篇 |
1985年 | 21篇 |
1984年 | 5篇 |
1983年 | 6篇 |
1982年 | 17篇 |
1981年 | 9篇 |
1980年 | 12篇 |
1978年 | 8篇 |
1977年 | 11篇 |
1976年 | 9篇 |
1975年 | 9篇 |
1973年 | 3篇 |
1953年 | 2篇 |
排序方式: 共有1504条查询结果,搜索用时 31 毫秒
31.
32.
Diabetes mellitus (particularly type 2) and osteoporosis are two very common disorders, and both are increasing in prevalence. Adolescents with type 1 diabetes mellitus may not reach potential peak bone mass, putting them at greater fracture risk. In adults with type 2 diabetes, fracture risk is increased and is not explained by the bone mineral density measured by dual-energy X-ray absorptiometry, still considered the gold standard predictor of fracture. In this review, we explore potential mechanisms behind the increased fracture risk that occurs in patients with diabetes, even those with increased bone mineral density. One potential link between diabetes and bone is the osteoblast-produced factor, osteocalcin. It remains to be established whether osteocalcin reflects or affects the connection between bone and glucose metabolism. Several other potential mediators of the effects of diabetes on bone are discussed. 相似文献
33.
Chronic hepatitis C burden and care cascade in Australia in the era of interferon‐based treatment
下载免费PDF全文
![点击此处可从《Journal of gastroenterology and hepatology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
34.
35.
36.
继续医学教育的目的是通过向医生提供最新的医学知识和技能,使医生在其整个职业生涯中,一直保持较高的医疗水平.但目前还没有充足的证据能证明继续医学教育活动的有效性,以及在继续医学教育活动中哪些教育方法和技术能最有效地传播和记忆医学知识.为了全面、系统地评估继续医学教育活动的有效性,以及了解不同的教育手段对医生知识、态度、技能、临床表现和临床效果的作用.美国约翰·霍普金斯大学医学院、美国医疗保健研究与质量管理署和美国胸科医师学会的专家共同进行了一项系统回顾性研究. 相似文献
37.
Mouse bone marrow (BM) was separated into low-density, lineage- negative, wheat germ agglutinin-positive (WGA+), Rhodamine-123 bright (Rhbright) or dim (Rhdim) cells to obtain populations that were highly enriched for committed progenitors (Rhbright cells) or for more primitive stem cells (Rhdim). When 2,500 Rhbright or Rhdim cells were seeded onto 6-week-old irradiated (20 Gy) long-term BM cultures (LTBMC), the nonadherent cell production from Rhbright cells was transient and ended after 5 weeks. Production from Rhdim cells did not begin until week 3, peaked at week 5, and ended at week 8, when the irradiated stroma seemed to fail. Termination of cell production from Rhdim cells did not occur in nonirradiated LTBMC from W41/Wv mice. During peak nonadherent cell production, 25% to 30% of the cells in the nonirradiated LTBMC from W41/Wv mice had donor cell markers. Two approaches were tested to try to enhance the proportion or number of donor cells. Addition of Origen-HGF at the time of seeding Rhdim cells caused a nonspecific increase in both host and donor cell production, but a specific increase in production of donor cells was obtained by seeding the cultures at 2 weeks rather than 6 weeks. Limiting dilution of Rhdim cells gave the same frequency of wells producing cells on both irradiated +/+ and nonirradiated W41/Wv or W/Wv cultures. 相似文献
38.
Liu SC; Palek J; Yi SJ; Nichols PE; Derick LH; Chiou SS; Amato D; Corbett JD; Cho MR; Golan DE 《Blood》1995,86(1):349-358
Southeast Asian ovalocytosis (SAO) is an asymptomatic trait characterized by rigid, poorly deformable red cells that resist invasion by several strains of malaria parasites. The underlying molecular genetic defect involves simple heterozygous state for a mutant band 3 protein, which contains a deletion of amino acids 400 through 408, linked with a Lys 56-to-Glu substitution (band 3-Memphis polymorphism). To elucidate the contribution of the mutant SAO band 3 protein to increased SAO red blood cell (RBC) rigidity, we examined the participation of the mutant SAO band 3 protein in increased band 3 attachment to the skeleton and band 3 oligomerization. We found first that SAO RBC skeletons retained more band 3 than normal cells and that this increased retention preferentially involved the mutant SAO band 3 protein. Second, SAO RBCs contained a higher percentage of band 3 oligomer-ankyrin complexes than normal cells, and these oligomers were preferentially enriched by the mutant SAO protein. At the ultrastructural level, the increased oligomer formation of SAO RBCs was reflected by stacking of band 3-containing intramembrane particles (IMP) into longitudinal strands. The IMP stacking was not reversed by treating SAO RBCs in alkaline pH (pH 11), which is known to weaken ankyrin-band 3 interactions, or by removing the cytoplasmic domain of band 3 from SAO membranes with trypsin. Finally, we found that band 3 protein in intact SAO RBCs exhibited a markedly decreased rotational mobility, presumably reflecting the increased oligomerization and the membrane skeletal association of the SAO band 3 protein. We propose that the mutant SAO band 3 has an increased propensity to form oligomers, which appear as longitudinal strands of IMP and exhibit increased association with membrane skeleton. This band 3 oligomerization underlies the increase in membrane rigidity by precluding membrane skeletal extension, which is necessary for membrane deformation. 相似文献
39.
Razavi Yasaman Keyhanfar Fariborz Haghparast Abbas Shabani Ronak Mehdizadeh Mehdi 《Metabolic brain disease》2021,36(6):1381-1390
Metabolic Brain Disease - Chronic methamphetamine (meth) abuse can lead to certain deficits in the hippocampal function by affecting the hippocampal neurogenesis and plasticity. To determine... 相似文献
40.
C. Tobon-Gomez N. Duchateau R. Sebastian S. Marchesseau O. Camara E. Donal M. De Craene A. Pashaei J. Relan M. Steghofer P. Lamata H. Delingette S. Duckett M. Garreau A. Hernandez K. S. Rhode M. Sermesant N. Ayache C. Leclercq R. Razavi N. P. Smith A. F. Frangi 《Medical & biological engineering & computing》2013,51(11):1235-1250