全文获取类型
收费全文 | 7001篇 |
免费 | 802篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 127篇 |
儿科学 | 260篇 |
妇产科学 | 90篇 |
基础医学 | 919篇 |
口腔科学 | 92篇 |
临床医学 | 796篇 |
内科学 | 1637篇 |
皮肤病学 | 115篇 |
神经病学 | 666篇 |
特种医学 | 174篇 |
外科学 | 1085篇 |
综合类 | 121篇 |
一般理论 | 9篇 |
预防医学 | 599篇 |
眼科学 | 175篇 |
药学 | 390篇 |
中国医学 | 3篇 |
肿瘤学 | 555篇 |
出版年
2023年 | 83篇 |
2022年 | 136篇 |
2021年 | 373篇 |
2020年 | 188篇 |
2019年 | 270篇 |
2018年 | 305篇 |
2017年 | 211篇 |
2016年 | 177篇 |
2015年 | 255篇 |
2014年 | 300篇 |
2013年 | 297篇 |
2012年 | 468篇 |
2011年 | 469篇 |
2010年 | 235篇 |
2009年 | 175篇 |
2008年 | 339篇 |
2007年 | 326篇 |
2006年 | 260篇 |
2005年 | 263篇 |
2004年 | 257篇 |
2003年 | 213篇 |
2002年 | 210篇 |
2001年 | 149篇 |
2000年 | 136篇 |
1999年 | 121篇 |
1998年 | 32篇 |
1997年 | 32篇 |
1996年 | 36篇 |
1995年 | 36篇 |
1993年 | 33篇 |
1992年 | 94篇 |
1991年 | 101篇 |
1990年 | 103篇 |
1989年 | 98篇 |
1988年 | 82篇 |
1987年 | 90篇 |
1986年 | 81篇 |
1985年 | 80篇 |
1984年 | 58篇 |
1983年 | 53篇 |
1982年 | 34篇 |
1981年 | 31篇 |
1979年 | 42篇 |
1978年 | 31篇 |
1976年 | 39篇 |
1974年 | 34篇 |
1973年 | 34篇 |
1972年 | 29篇 |
1971年 | 30篇 |
1967年 | 28篇 |
排序方式: 共有7813条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
Facundo Davaro Jacob Roberts Allison May Coleman McFerrin Sameer Siddiqui Zachary Hamilton 《Journal of robotic surgery》2020,14(3):447-454
Partial nephrectomy is the mainstay of treatment for localized kidney cancer. A proportion of patients are upstaged post-operatively to locally advanced di 相似文献
5.
6.
Health care use among young children in day care. Results in a randomized trial of early intervention 总被引:2,自引:0,他引:2
Exposure of young children to group day-care settings increases the risk of illness and may result in higher use of medical care. These observations raise concerns that the use of such settings for early intervention programs for low-birth-weight infants may increase the already high burden of medical care costs incurred by these children and their families. To address the question of medical care use associated with center-based care, we examined the hospital-based and ambulatory care reported for participants of the Infant Health and Development Program. This project is a multisite randomized trial of an early intervention program for preterm low-birth-weight infants with an intervention including 2 years of center-based care. The Intervention group did not differ in hospital-based care and averaged only two more physicians' visits over the 3-year observation period than the comparison group. We conclude that early intervention programs involving high-quality group care are not accompanied by substantial increases in health care use. 相似文献
7.
Satellite cells express distinct patterns of myogenic proteins in immature skeletal muscle. 总被引:1,自引:0,他引:1
Edward Schultz Connie Chamberlain Kathleen M McCormick Paul E Mozdziak 《Developmental dynamics》2006,235(12):3230-3239
Satellite cells are the myogenic cells lying between the myofiber sarcolemma and basal lamina. The objective of this study was to determine the expression patterns of MyoD, myogenin, and Pax7 within the satellite cell population in the growing rat soleus and extensor digitorum longus (EDL) muscles. Secondly, the expression of the myogenic markers was also studied within the interstitial cell compartment and myonuclei. It was discovered that the soleus contained a higher number of Pax7, MyoD, or myogenin-positive nuclei compared with the EDL. Similarly, myogenin was expressed at a lower level in the myonuclei of the soleus compared with the EDL, and myogenin was expressed at a higher level in the interstitial compartment of the soleus compared with the EDL. When interstitial nuclei, myonuclei, and double-labeled nuclei were used in the estimate of the satellite cell population, it was discovered that approximately of 13% of the myofibers in a transverse section of the soleus muscle and 4.1% of EDL myofibers exhibit a labeled satellite cell nucleus. Overall, results from this study suggest that expression patterns of these markers vary predictably among muscles with different growth dynamics and phenotypic characteristics. 相似文献
8.
Beyond C4d: Other Complement-Related Diagnostic Approaches to Antibody-Mediated Rejection 总被引:3,自引:0,他引:3
William M. Baldwin III Edward K. Kasper rea A. Zachary Barbara A. Wasowska E. Rene Rodriguez 《American journal of transplantation》2004,4(3):311-318
Complement is a multifunctional system of receptors and regulators as well as effector molecules. Both the pathogenic and diagnostic power of complement is based on the capacity of the complement system to amplify innate and adaptive immunity. This amplification is accomplished through two strategies: (1) enzymatic reactions in the complement cascade, and (2) stimulation of leukocytes, platelets and parenchymal cells through specific receptors or receptor-independent pore formation. The mechanisms by which complement mediates and modifies nonspecific inflammation, antibody-mediated injury and T-cell responses are of particular significance to the pathogenesis of transplant rejection. Understanding the mechanisms by which complement integrates the interactions of leukocytes, platelets and parenchymal cells offers opportunities to further refine the diagnosis of rejection. 相似文献
9.
Proteins that enter the secretory pathway play important roles in virulence and pathogenesis in Candida albicans, but our understanding of the trafficking of these proteins is in its early stages. In Saccharomyces cerevisiae, dominant negative alleles of YPT1 and SEC4 interrupt secretory traffic at pre- and post-Golgi steps, respectively. We therefore used a dominant negative genetic approach to examine the intracellular trafficking of several proteins associated with virulence or azole resistance. When the dominant negative ypt1(N121I) allele of C. albicans was overexpressed, yellow-fluorescent protein (YFP) tagged forms of two plasma membrane transporters (Cdrlp and Ftrlp) and the vacuolar membrane ABC transporter Mltlp accumulated in intracellular structures that appeared related to the ER, but localization of Cdc10p and Int1p was unaffected. When the dominant negative sec4(S28N) allele of C. albicans was overexpressed, Cdrlp and Ftrlp accumulated intracellularly, and localization of Mltlp, Cdc10p and Int1p was unaffected. These results imply that (i) Cdrlp and Ftrlp are transported to the plasma membrane by the general secretory pathway, (ii) Mlt1p enters the secretory pathway but is diverted to the vacuole at an early post-Golgi step, and (iii) like Cdc10p, Int1p does not enter the general secretory pathway. 相似文献
10.
D. McCormick 《Neuropathology and applied neurobiology》1993,19(2):146-151
There is evidence from investigations of non-CNS neoplasms that secreted proteolytic enzymes may facilitate tumour invasion by partially degrading extracellular matrix (ECM). Among the enzymes which may be involved are members of the cysteine proteinase superfamily and especially cathepsin B (CB). In the present investigation we have studied CB in human gliomas in vitro , concentrating particularly on CB secretion, as extracellular enzyme is of prime importance in this context. We have found that CB is secreted by gliomas in vitro as a latent zymogen, requiring activation. This has been confirmed by gel chromatography which indicated that CB is secreted as a 42 kDa proenzyme which may be proteolytically processed to an enzymatically active 29 kDa molecule. The inactive, high molecular weight, latent CB is stable at extracellular pH in contrast to the activated low molecular weight form which rapidly loses activity at this pH. We have also measured secretion of cysteine proteinase inhibitors (CPI), as their presence would have a direct influence on the effective activity of CB, and found that all of the gliomas secreted significant amounts of a CPI as assessed by papain inhibition. Our experiments suggest that a number of factors are involved in the regulation of extracellular glioma-derived CB activity. These include: rate of secretion of pro-CB, rate of CB activation, destabilization of CB at neutral pH and the presence of cysteine proteinase inhibitors. 相似文献