全文获取类型
收费全文 | 384066篇 |
免费 | 25104篇 |
国内免费 | 2835篇 |
专业分类
耳鼻咽喉 | 5271篇 |
儿科学 | 8330篇 |
妇产科学 | 10219篇 |
基础医学 | 53893篇 |
口腔科学 | 11904篇 |
临床医学 | 30506篇 |
内科学 | 79445篇 |
皮肤病学 | 8757篇 |
神经病学 | 27645篇 |
特种医学 | 14104篇 |
外国民族医学 | 82篇 |
外科学 | 61583篇 |
综合类 | 9991篇 |
现状与发展 | 1篇 |
一般理论 | 64篇 |
预防医学 | 17572篇 |
眼科学 | 9509篇 |
药学 | 31339篇 |
1篇 | |
中国医学 | 2211篇 |
肿瘤学 | 29578篇 |
出版年
2021年 | 2719篇 |
2019年 | 2797篇 |
2018年 | 4616篇 |
2017年 | 3535篇 |
2016年 | 3602篇 |
2015年 | 4150篇 |
2014年 | 5839篇 |
2013年 | 7523篇 |
2012年 | 10268篇 |
2011年 | 10538篇 |
2010年 | 6352篇 |
2009年 | 6002篇 |
2008年 | 9718篇 |
2007年 | 10604篇 |
2006年 | 10507篇 |
2005年 | 9566篇 |
2004年 | 9047篇 |
2003年 | 8815篇 |
2002年 | 8449篇 |
2001年 | 28415篇 |
2000年 | 28948篇 |
1999年 | 23818篇 |
1998年 | 5225篇 |
1997年 | 4322篇 |
1996年 | 3895篇 |
1995年 | 3538篇 |
1994年 | 3151篇 |
1993年 | 2880篇 |
1992年 | 16151篇 |
1991年 | 14892篇 |
1990年 | 14252篇 |
1989年 | 14049篇 |
1988年 | 12669篇 |
1987年 | 12126篇 |
1986年 | 11162篇 |
1985年 | 10391篇 |
1984年 | 6971篇 |
1983年 | 5644篇 |
1982年 | 2740篇 |
1979年 | 5527篇 |
1978年 | 3377篇 |
1977年 | 3001篇 |
1975年 | 2665篇 |
1974年 | 3091篇 |
1973年 | 2886篇 |
1972年 | 2845篇 |
1971年 | 2782篇 |
1970年 | 2533篇 |
1969年 | 2574篇 |
1968年 | 2273篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
To examine the prevalence of Internet sex networking among men who have sex with men (MSM) in Hong Kong and risk behaviors associated with the behavior, a telephone survey of 15,230 Hong Kong Chinese men aged 18-60 was conducted. Of the 283 active MSM (having engaged in some MSM behaviors in the last 6 months) identified, 17.7% had networked for MSM partners via the Internet in the last 6 months. Younger age (odds ratio [OR] for age < or = 25 vs. age >25 = 4.67, 95% confidence interval [CI] = 2.35-9.28) and being an anal-sex MSM (OR = 4.72, 95% CI=2.36-9.44) were independent predictors of Internet sex networking. Being an Internet sex networker was associated with some risk behaviors such as having contracted a sexually transmitted disease (adjusted OR = 4.79, 95% CI = 1.34-17.11), having had > or = 3 MSM partners (adjusted OR = 4.74, 95% CI = 2.20-10.23), and having engaged in anal sex (adjusted OR = 3.95, 95% CI = 1.89-8.23). HIV prevention programs for MSM should thereby include Internet-based interventions. 相似文献
103.
S. Vitko Z. Wlodarczyk L. Kyllönen Z. Czajkowski R. Margreiter L. Backman F. Perner P. Rigotti B. Jaques D. Abramowicz M. Kessler J. Sanchez-Plumed L. Rostaing R.S. Rodger D. Donati Y. Vanrenterghem 《American journal of transplantation》2006,6(3):531-538
Tacrolimus combined with mycophenolate mofetil (MMF) is an effective regimen in kidney transplantation. This study compared the efficacy of combining tacrolimus and two different dosages of sirolimus with an established tacrolimus-MMF regimen. Each day in addition to tacrolimus, 325 patients received 2 mg sirolimus (TAC-SRL2 mg), 325 patients received 0.5 mg sirolimus (TAC-SRL0.5 mg) and 327 patients 1 g MMF (TAC-MMF). The initial tacrolimus dose was 0.2 mg/kg/day. Sirolimus patients received loading doses of 6 or 1.5 mg, and daily doses of 2 or 0.5 mg thereafter. Steroid administration was identical for all groups. The incidence of biopsy-proven acute rejection was lower in the TAC-SRL2 mg group (15.7%) compared with the TAC-SRL0.5 mg (25.2%, p = 0.003) and the TAC-MMF groups (22.3%, p = 0.036). Six-month graft survival was 91.0% (TAC-SRL2 mg), 92.6% (TAC-SRL0.5 mg) and 92.4% (TAC-MMF); the respective values for patient survival were 98.1%, 97.8% and 97.9%. Thirty-four patients (10.5%), 19 patients (5.8%) and 16 patients (4.9%) in the TAC-SRL2 mg, TAC-SRL0.5 mg and TAC-MMF groups, respectively, discontinued the study because of adverse events. Hyperlipemia was reported more often in the TAC-SRL2 mg group (24.0%) compared with 19.4% (TAC-SRL0.5 mg) and 11.0% (TAC-MMF; p < 0.05). Combining 2 mg sirolimus/day with tacrolimus results in lower rates of acute rejection, but a higher incidence of adverse events. 相似文献
104.
105.
106.
107.
108.
109.
Association between commensal bacteria and opportunistic pathogens in the dental plaque of elderly individuals 总被引:2,自引:0,他引:2
A. Tada H. Senpuku Y. Motozawa A. Yoshihara N. Hanada H. Tanzawa 《Clinical microbiology and infection》2006,12(8):776-781
Opportunistic infections in the oral cavity of the elderly may increase the incidence of systemic disease. The objective of this study was to investigate the differences in the oral bacterial flora between dependent elderly (inpatients) and independent elderly (community-dwelling residents). After multiple variables were taken into account, inpatients had significantly lower detection rates than community-dwelling residents for alpha-streptococci (p < 0.001) and Neisseria (p 0.004), and higher detection rates for Pseudomonas aeruginosa (p 0.024), methicillin-resistant Staphylococcus aureus (MRSA) (p 0.011) and Actinomyces spp. (p 0.005). Among inpatients, the requirement for a high degree of care was related negatively to detection of alpha-streptococci, but was related significantly to detection of P. aeruginosa (p 0.018) or MRSA (p 0.004). Tube-fed inpatients had a significantly lower detection rate for alpha-streptococci (p 0.041) and a higher detection rate for P. aeruginosa (p 0.004) than those who did not require tube feeding. Inpatients with a history of antibiotic use had a significantly lower detection rate for alpha-streptococci (p 0.049) and a higher detection rate for MRSA (p 0.007) than those without a history of antibiotic use. The detection rates for P. aeruginosa or MRSA in inpatients without alpha-streptococci were higher than in inpatients with alpha-streptococci after controlling for age and gender (P. aeruginosa, p 0.006; MRSA, p 0.001). Overall, detection of alpha-streptococci had an inverse correlation with the detection of P. aeruginosa and MRSA in the oral cavity and is likely to be an indicator of pathogenic bacterial infection. 相似文献
110.
Katsuo Kamata Ayako Makino Noriyasu Kanie Shu-ichi Oda Takayuki Matsumoto Tsuneo Kobayashi Toyohiko Kikuchi Masato Nishimura Toshio Honda 《Journal of Smooth Muscle Research》2006,42(2-3):75-88
Anthocyanins, which are responsible for a variety of bright colors (including red, blue, and purple) in fruits, vegetables, and flowers, are consumed as dietary polyphenols. Anthocyanin-containing fruits are thought to decrease coronary heart disease and are used in anti-diabetic preparations. Diabetes is associated with a variety of cardiovascular complications that may be mediated by endothelial dysfunction, and so this study was designed mainly to characterize the influence of a synthesized anthocyanidin derivative (HK-008) over acetylcholine (ACh)-induced relaxation in mesenteric arterial beds isolated from rats. In a glucose-tolerance test in intact rats, HK-008 (30 mg/kg) reduced the glucose level as effectively as the same dose of glibenclamide. The aortic relaxation induced by pinacidil (an ATP-sensitive potassium channel opener) was greatly inhibited by glibenclamide (10 microM), and also significantly inhibited by HK-008 (10 microM). Interestingly, the ACh-induced relaxation in the perfused, preconstricted mesenteric arterial bed was significantly enhanced by HK-008 (10 microM), and this enhancement was significantly attenuated by indomethacin (10 microM). The ACh-induced mesenteric relaxation was impaired by an increase in oxidative stress, viz. superoxide-generating treatment [xanthine oxidase (XO; 0.1 U/ml) plus hypoxanthine (HX; 10 microM)]. However, this impairment was strongly suppressed by HK-008 (10 microM). These results suggest that HK-008 increases endothelium-induced relaxation by suppressing oxidative stress or modulating prostanoids signaling. This compound may therefore be useful against certain cardiovascular disorders. 相似文献