全文获取类型
收费全文 | 14500篇 |
免费 | 954篇 |
国内免费 | 50篇 |
专业分类
耳鼻咽喉 | 76篇 |
儿科学 | 415篇 |
妇产科学 | 396篇 |
基础医学 | 1713篇 |
口腔科学 | 178篇 |
临床医学 | 2248篇 |
内科学 | 2999篇 |
皮肤病学 | 178篇 |
神经病学 | 1412篇 |
特种医学 | 241篇 |
外科学 | 1297篇 |
综合类 | 388篇 |
一般理论 | 18篇 |
预防医学 | 2031篇 |
眼科学 | 262篇 |
药学 | 634篇 |
中国医学 | 15篇 |
肿瘤学 | 1003篇 |
出版年
2023年 | 78篇 |
2022年 | 90篇 |
2021年 | 261篇 |
2020年 | 152篇 |
2019年 | 239篇 |
2018年 | 284篇 |
2017年 | 217篇 |
2016年 | 230篇 |
2015年 | 289篇 |
2014年 | 430篇 |
2013年 | 694篇 |
2012年 | 976篇 |
2011年 | 1123篇 |
2010年 | 593篇 |
2009年 | 522篇 |
2008年 | 999篇 |
2007年 | 1051篇 |
2006年 | 1001篇 |
2005年 | 1000篇 |
2004年 | 976篇 |
2003年 | 887篇 |
2002年 | 837篇 |
2001年 | 119篇 |
2000年 | 104篇 |
1999年 | 140篇 |
1998年 | 210篇 |
1997年 | 150篇 |
1996年 | 131篇 |
1995年 | 122篇 |
1994年 | 105篇 |
1993年 | 94篇 |
1992年 | 73篇 |
1991年 | 62篇 |
1990年 | 65篇 |
1989年 | 71篇 |
1988年 | 59篇 |
1987年 | 47篇 |
1986年 | 53篇 |
1985年 | 53篇 |
1984年 | 66篇 |
1983年 | 81篇 |
1982年 | 73篇 |
1981年 | 77篇 |
1980年 | 63篇 |
1979年 | 48篇 |
1978年 | 52篇 |
1977年 | 43篇 |
1976年 | 37篇 |
1975年 | 31篇 |
1974年 | 31篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
101.
Joan McCutcheon Rosemary A. Walker 《Virchows Archiv : an international journal of pathology》1987,410(5):369-374
Summary The significance of demonstrating argyrophilia in human breast carcinomas is a complex issue, although there is general agreement that true carcinoid tumours of the breast are rare.A predominantly unselected series of breast carcinomas has been investigated for evidence of argyrophilia using the Churukian Schenk method (Churukian and Schenk 1979), alpha lactalbumin and prealbumin, a marker of neuroendocrine cells.Argyrophilia has been detected in 25% of carcinomas, including all of mucinous types. However, only 4 of the 68 tumours had a diffuse cytoplasmic reaction typical of that seen in neuroendocrine cells. The others showed a focal or subluminal/ peripheral reaction. Those argyrophilic carcinomas with demonstrable alpha lactalbumin had this latter pattern of reactivity, although the milk protein was always detected in lesser amounts by comparison. Prealbumin was only found to varying degrees in eight tumours and the majority of these had a diffuse or focal cytoplasmic argyrophilic reaction.It would appear that in only a small number of breast carcinomas, approximately six percent, does the presence of argyrophilia probably represent neuroendocrine differentiation, whilst in others it is related to the secretory nature of the tumour cells. 相似文献
102.
Laura J. Solomon Brian S. Flynn John K. Worden Ruth M. Mickey Joan M. Skelly Berta M. Geller Nancy W. Peluso Jacqueline A. Webster 《Journal of behavioral medicine》1998,21(1):83-102
This study examined the relative impact of different self-reward strategies on maintenance of breast self-examination (BSE) practice among 1649 women trained to do BSE. Training groups were randomized into four conditions: (a) self-reward instructions and materials delivered at the end of the BSE training session; (b) self-reward suggestions delivered through the mail each month, contingent upon the BSE performance; (c) external monetary rewards and self-reward suggestions delivered through the mail each month on an intermittent schedule, contingent upon BSE practice; and (d) a no-reward control condition. Follow-up assessments 12 months following training revealed a pattern of evidence in support of the benefits of external monetary rewards and self-reward prompts on BSE frequency and quality; however, it is likely that the value of that condition lies in the external reward component. 相似文献
103.
104.
CXCR4-transgene expression significantly improves marrow engraftment of cultured hematopoietic stem cells 总被引:4,自引:0,他引:4
Brenner S Whiting-Theobald N Kawai T Linton GF Rudikoff AG Choi U Ryser MF Murphy PM Sechler JM Malech HL 《Stem cells (Dayton, Ohio)》2004,22(7):1128-1133
Hematopoietic stem cells (HSCs) lose marrow reconstitution potential during ex vivo culture. HSC migration to stromal cell-derived factor (SDF)-1 (CXCL12) correlates with CXC chemokine receptor 4 (CXCR4) expression and marrow engraftment. We demonstrate that mobilized human CD34+ peripheral blood stem cells (CD34+ PBSCs) lose CXCR4 expression during prolonged culture. We transduced CD34+ PBSCs with retrovirus vector encoding human CXCR4 and achieved 18-fold more CXCR4 expression in over 87% of CD34+ cells. CXCR4-transduced cells yielded increased calcium flux and up to a 10-fold increase in migration to SDF-1. Six-day cultured CXCR4-transduced cells demonstrated significant engraftment in nonobese diabetic/severe combined immunodeficient mice under conditions in which control transduced cells resulted in low or no engraftment. We conclude that transduction-mediated overexpression of CXCR4 significantly improves marrow engraftment of cultured PBSCs. 相似文献
105.
Rabon-Stith KM Hagberg JM Phares DA Kostek MC Delmonico MJ Roth SM Ferrell RE Conway JM Ryan AS Hurley BF 《Experimental physiology》2005,90(4):653-661
To determine the influence of the vitamin D receptor (VDR) gene FokI and BsmI genotype on bone mineral density response to two exercise training modalities, 206 healthy men and women (50-81 years old) were studied before and after approximately 5-6 months of either aerobic exercise training (AT) or strength training (ST). A totla of 123 subjects completed AT (51 men, 72 women) and 83 subjects completed ST (40 men, 43 women). DNA was extracted from blood samples of all subjects and genotyping was performed at the VDR FokI and BsmI locus to determine its association to training response. Total body, greater trochanter and femoral neck bone mineral density (BMD) were measured before and after both training programmes using dual-energy X-ray absorptiometry. VDR BsmI genotype was not significantly related to BMD at baseline or after ST or AT. However, VDR FokI genotype was significantly related to ST- but not AT-induced changes in femoral neck BMD (P < 0.05). The heterozygotes (Ff) in the ST group approached a significantly greater increase in femoral neck BMD (P = 0.058) compared to f homozygotes. There were no significant genotype relationships in the AT group. These data indicate that VDR FokI genotype may influence femoral neck BMD response to ST, but not AT. 相似文献
106.
107.
Patterson Thomas L.; Sallis James F.; Nader Philip R.; Kaplan Robert M.; Rupp Joan W.; Atkins Catherine J.; Senn Karen L. 《Journal of pediatric psychology》1989,14(2):277-292
A number of studies have demonstrated that physiological andbehavioral cardiovascular disease (CVD) risk factors aggregatewithin families. This fact, and the potential mediating rolethat the family plays in behavior change, have led to the developmentof family-based CVD risk reduction programs, including the SanDiego Family Health Project. The aggregation of behavioral,physiological, and cognitive changes within families was assessedduring a 1-year intervention. We found evidence of modest butsignificant aggregation of change. There was more aggregationof change in behavioral variables than in physiological or cognitivevariables. More significant correlations were found among 3-dayfood record measures than among 24-hour recall dietary measures,suggesting an influence of assessment method. Aggregation ofchange within families was stronger within generations thanacross generations. These data point to the importance of involvingall age groups in health promotion programs. 相似文献
108.
Myrin Borysenko Samuel Turesky Joan Z. Borysenko Fred Quimby Herbert Benson 《Journal of behavioral medicine》1980,3(3):233-243
The stress of crowding and exposure to inescapable electric shock increased both the incidence and the severity of dental caries in rats housed in a conventional animal facility. Male Osborne-Mendel rats were inoculated intraorally with cariogenic bacteria, fed a high-sucrose diet, and housed in either a conventional or a sheltered facility. Rats in both housing conditions were subdivided into control and stress groups. At the end of the 56-day trial period, stressed rats from conventional housing had a significant increase in both incidence and severity of dental caries in comparison to their controls. In contrast, stressed rats from sheltered housing had a trend toward increased cariogenesis which reached significance in only one of five scores. These rats also failed to gain weight comparable to their controls, making it possible that stress-induced reduction in appetite partially offset stress-induced exacerbation in cariogenesis.This investigation was supported in part by the following Grants from the United States Public Health Service: CA 20093, HL 22727, and HL 07374. 相似文献
109.
Joan C. Rener 《Methods in Cell Science》1985,9(3):187-189
Summary Hybridoma cell lines grown as ascites tumors in pristane primed mice will frequently yield milligram quantities of monoclonal antibody per milliliter of ascites fluid. Ascites production is an excellent method for the research scientist to generate high titer antibody with minimal effort. Through commercial production, gram to kilogram quantities can be achieved. 相似文献
110.