全文获取类型
收费全文 | 2086篇 |
免费 | 131篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 18篇 |
儿科学 | 56篇 |
妇产科学 | 32篇 |
基础医学 | 307篇 |
口腔科学 | 64篇 |
临床医学 | 156篇 |
内科学 | 528篇 |
皮肤病学 | 45篇 |
神经病学 | 141篇 |
特种医学 | 69篇 |
外科学 | 185篇 |
综合类 | 5篇 |
一般理论 | 1篇 |
预防医学 | 117篇 |
眼科学 | 54篇 |
药学 | 210篇 |
中国医学 | 2篇 |
肿瘤学 | 236篇 |
出版年
2023年 | 16篇 |
2022年 | 33篇 |
2021年 | 66篇 |
2020年 | 37篇 |
2019年 | 44篇 |
2018年 | 52篇 |
2017年 | 31篇 |
2016年 | 34篇 |
2015年 | 70篇 |
2014年 | 61篇 |
2013年 | 90篇 |
2012年 | 170篇 |
2011年 | 151篇 |
2010年 | 89篇 |
2009年 | 72篇 |
2008年 | 145篇 |
2007年 | 173篇 |
2006年 | 167篇 |
2005年 | 142篇 |
2004年 | 127篇 |
2003年 | 132篇 |
2002年 | 99篇 |
2001年 | 21篇 |
2000年 | 14篇 |
1999年 | 25篇 |
1998年 | 29篇 |
1997年 | 16篇 |
1996年 | 14篇 |
1995年 | 18篇 |
1994年 | 16篇 |
1993年 | 14篇 |
1992年 | 12篇 |
1991年 | 7篇 |
1990年 | 6篇 |
1989年 | 6篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 5篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1962年 | 1篇 |
排序方式: 共有2226条查询结果,搜索用时 15 毫秒
991.
992.
The development of nerve-sparing procedures is important in preventing bladder dysfunction following radical hysterectomy. In this study, we dissected 14 halves of 7 female pelvises (age range: 46-86 years; mean age: 74 years) to examine the origins, courses, and distributions of nerve branches to the bladder in females in detail, and 6 halves of 3 male pelvises (age range: 71-85 years, mean age: 78 years) to compare with the female specimens. Nerve branches to the bladder originated mainly from the inferior hypogastric plexus, but independent direct branches running along the ureter from the hypogastric nerve were also distributed particularly to the trigone in all female specimens. We classified these independent branches into four types according to their relationship to the ureter. In males the numbers of the independent branches were small and they were difficult to find. The present observations indicate that nerve distribution patterns to the bladder differ between females and males. In nerve sparing procedures for radical hysterectomy, the area between the ureter and the hypogastric nerve is important. 相似文献
993.
Anpo M Shirayama K Tsutsui T 《Odontology / the Society of the Nippon Dental University》2011,99(2):188-192
The cytotoxic effect of eugenol on the expression of molecular markers related to the osteogenic differentiation of human
dental pulp cells such as collagen synthesis and the expression of two osteogenesis-related genes, alkaline phosphatase (ALP)
and bone sialoprotein (BSP), was studied using human dental pulp cells (D824 cells). Cellular growth and survival were decreased
by treatment of cells with eugenol in a concentration-dependent manner. The incorporation rate of [3H] proline into the acid-insoluble fraction and the synthesis of type I–V collagens were also reduced by treatment of cells
with eugenol in a concentration-dependent fashion. The mRNA expression of ALP was scarcely affected in cells exposed to eugenol,
whereas the mRNA and protein expression of BSP was down-regulated depending on the concentrations of eugenol. The results
suggest that because collagen synthesis and BSP expression play a critical role in hard tissue formation, eugenol used for
endodontic treatment may give rise to cytotoxic effects to the normal function of stem cells reported to exist in human dental
pulp tissue and periodontal ligament. 相似文献
994.
995.
Iida T Kawato T Tanaka H Tanabe N Nakai K Zhao N Suzuki N Ochiai K Maeno M 《Archives of oral biology》2011,56(7):678-686
ObjectiveSodium butyrate (butyric acid; BA) is a major metabolic by-product of the anaerobic periodontopathic bacteria present in subgingival plaque. We examined the effects of BA and/or indomethacin on cell proliferation, the expression of cyclooxygenases (COXs), prostaglandin (PG) receptors (EP1-4), extracellular matrix proteins, such as type I collagen and osteopontin, and PGE2 production, using ROS17/2.8 cells as osteoblasts.MethodsThe rat clonal cell line ROS 17/2.8 was cultured with 0, 10?5, 10?4, and 10?3 M BA in the presence or absence of 0.5 μM indomethacin, for up to 7 days. The expression of COX-1, COX-2, EP1, EP2, EP3, EP4, type I collagen, and osteopontin was examined at the mRNA and protein levels using real-time PCR and Western blotting, respectively. The amount of PGE2 in the culture medium was measured by ELISA.ResultsProliferation of ROS 17/2.8 cells was not affected by the addition of BA. However, PGE2 production and the expression of COX-1 and COX-2 increased with the addition of BA. In contrast, indomethacin, an inhibitor of COX, blocked the stimulatory effect of BA. Furthermore, EP2 expression increased with BA treatment, whereas EP1 expression was not affected and the expression of EP3 and EP4 was not detected. The addition of BA also increased the expression of type I collagen and osteopontin. Indomethacin blocked about 50% of the stimulatory effect of BA on type I collagen, whereas it did not block the effect on osteopontin.ConclusionsThese results suggest that BA induces PGE2 production by increasing the expression of COX-1 and COX-2 in osteoblasts, and that an autocrine action of the produced PGE2, via EP1 or BA-induced EP2, is related to an increase in type I collagen expression by BA. 相似文献
996.
997.
998.
The purpose of this study on the involvement of epigenetic control of the expression of solute carrier (SLC) transporters by DNA methylation and histone deacetylation in 4 colon cancer cells is to find the epigenetic control mechanisms of drug transporters in colon cancers. Human colon cancer cell lines (HCT116, HT29, SW48, SW480) were treated with 5-aza-2'-deoxycytidine (DAC), as a DNA methyltransferase inhibitor, followed by trichostatin A (TSA), as a histone deacetylase inhibitor. The mRNA expression and DNA methylation of several SLC transporters were analyzed by real-time polymerase chain reaction (PCR) and methylation-specific PCR, respectively. Among 12 SLC transporters possessing cytosine-phosphate-guanine (CpG) islands, thiamine transporter 2 (THTR2) (SLC19A3) gene showed a correlation between its mRNA expression level and DNA methylation status. TSA treatment increased histone H3 acetylation of THTR2 promoter region in all 4 colon cancer cell lines examined. HCT116 and SW48 cells showed a lack of THTR2 mRNA expression and methylation of its promoter, and DAC treatment induced its re-expression. In addition, the co-treatment with DAC and TSA increased THTR2 mRNA expression more markedly than DAC treatment in HCT116 and SW48 cells. In HT29 and SW480 cells that showed little methylation of THTR2 promoter, TSA treatment induced THTR2 mRNA expression markedly, but DAC treatment did not. In the 4 colon cancer cells examined, THTR2 mRNA expression is down-regulated by DNA methylation and/or histone deacetylation. 相似文献
999.
Miyagi T Shimizu S Tatsumi T Nishio K Hiramatsu N Kanto T Hayashi N Takehara T 《Journal of gastroenterology》2011,46(8):1020-1030
Background
Natural killer (NK) cells play an important role in immune responses to virus infection. The cell population consists of CD56bright (bright-subset) and CD56dim (dim-subset) subsets that possess armed functions of cytokine production and cytolysis, respectively. How these subsets are involved in chronic hepatitis C virus infection (CHC) remains obscure. 相似文献1000.
Daisuke Hatsushika Akimoto Nimura Tomoyuki Mochizuki Kumiko Yamaguchi Takeshi Muneta Keiichi Akita 《Knee surgery, sports traumatology, arthroscopy》2013,21(5):998-1004