全文获取类型
收费全文 | 1110篇 |
免费 | 72篇 |
国内免费 | 34篇 |
专业分类
儿科学 | 33篇 |
妇产科学 | 17篇 |
基础医学 | 97篇 |
口腔科学 | 25篇 |
临床医学 | 130篇 |
内科学 | 223篇 |
皮肤病学 | 19篇 |
神经病学 | 33篇 |
特种医学 | 125篇 |
外科学 | 114篇 |
综合类 | 100篇 |
预防医学 | 61篇 |
眼科学 | 4篇 |
药学 | 204篇 |
肿瘤学 | 31篇 |
出版年
2021年 | 7篇 |
2020年 | 7篇 |
2019年 | 10篇 |
2018年 | 9篇 |
2017年 | 10篇 |
2016年 | 11篇 |
2015年 | 15篇 |
2014年 | 19篇 |
2013年 | 28篇 |
2012年 | 36篇 |
2011年 | 41篇 |
2010年 | 23篇 |
2009年 | 33篇 |
2008年 | 46篇 |
2007年 | 79篇 |
2006年 | 49篇 |
2005年 | 53篇 |
2004年 | 50篇 |
2003年 | 37篇 |
2002年 | 33篇 |
2001年 | 36篇 |
2000年 | 35篇 |
1999年 | 42篇 |
1998年 | 46篇 |
1997年 | 29篇 |
1996年 | 26篇 |
1995年 | 27篇 |
1994年 | 23篇 |
1993年 | 19篇 |
1992年 | 19篇 |
1991年 | 21篇 |
1990年 | 20篇 |
1989年 | 35篇 |
1988年 | 25篇 |
1987年 | 17篇 |
1986年 | 22篇 |
1985年 | 10篇 |
1984年 | 15篇 |
1983年 | 12篇 |
1982年 | 9篇 |
1981年 | 15篇 |
1980年 | 13篇 |
1979年 | 7篇 |
1978年 | 14篇 |
1977年 | 7篇 |
1975年 | 10篇 |
1971年 | 8篇 |
1969年 | 5篇 |
1968年 | 10篇 |
1966年 | 5篇 |
排序方式: 共有1216条查询结果,搜索用时 15 毫秒
31.
Effects of electroacupuncture on gastric mucosal blood flow and transmucosal potential difference in stress rats 总被引:9,自引:0,他引:9
EfectsofelectroacupunctureongastricmucosalbloodflowandtransmucosalpotentialdiferenceinstressratsXUGuanSun1,SUNYong1,WANGZhe... 相似文献
32.
33.
Do acamprosate or naltrexone have an effect on daily drinking by reducing craving for alcohol? 总被引:1,自引:0,他引:1
Richardson K Baillie A Reid S Morley K Teesson M Sannibale C Weltman M Haber P 《Addiction (Abingdon, England)》2008,103(6):953-959
AIM: To explore the effect of acamprosate and naltrexone on craving and alcohol consumption in the treatment of alcohol dependence. DESIGN: A randomized, double-blind, single-dummy, placebo-controlled trial. SETTING: Three treatment centres in Sydney, Australia. PARTICIPANTS: A total of 169 alcohol-dependent subjects were given naltrexone (50 mg/day), acamprosate (1998 mg/day) or placebo for 12 weeks, in conjunction with manualized medication compliance therapy. INTERVENTION: During the course of the trial, participants kept a daily diary which included the number of standard drinks they consumed and their peak craving for alcohol that day rated on a 0-10 scale. MEASUREMENTS: Subjective ratings of daily craving and daily drinking for the first 6 weeks of treatment. FINDINGS: Mixed/hierarchical linear models were employed on an intention-to-treat basis. Analyses revealed that craving was a significant predictor of daily drinking and baseline levels of depression were the best predictor of daily craving. There was no significant improvement in model fit when treatment group was added both in models of daily craving and daily drinking. Daily alcohol consumption was best predicted by a model incorporating baseline dependence and depression scores, and daily craving, entered as a time-varying covariate. However, there was a significant craving x time x treatment interaction (t = -3.365, df = 4413.712, P < 0.001), suggesting that at higher levels of craving drinking was reduced at a significantly greater rate with naltrexone compared to acamprosate. CONCLUSIONS: Naltrexone had a greater effect on drinking when craving was high. These results support the role of naltrexone in reducing craving when that craving is highly salient. The role of acamprosate in reducing craving was not supported by these findings. 相似文献
34.
35.
Protective role of Bacillus anthracis exosporium in macrophage-mediated killing by nitric oxide 下载免费PDF全文
Weaver J Kang TJ Raines KW Cao GL Hibbs S Tsai P Baillie L Rosen GM Cross AS 《Infection and immunity》2007,75(8):3894-3901
The ability of the endospore-forming, gram-positive bacterium Bacillus anthracis to survive in activated macrophages is key to its germination and survival. In a previous publication, we discovered that exposure of primary murine macrophages to B. anthracis endospores upregulated NOS 2 concomitant with an .NO-dependent bactericidal response. Since NOS 2 also generates O(2).(-), experiments were designed to determine whether NOS 2 formed peroxynitrite (ONOO(-)) from the reaction of .NO with O(2).(-) and if so, was ONOO(-) microbicidal toward B. anthracis. Our findings suggest that ONOO(-) was formed upon macrophage infection by B. anthracis endospores; however, ONOO(-) does not appear to exhibit microbicidal activity toward this bacterium. In contrast, the exosporium of B. anthracis, which exhibits arginase activity, protected B. anthracis from macrophage-mediated killing by decreasing .NO levels in the macrophage. Thus, the ability of B. anthracis to subvert .NO production has important implications in the control of B. anthracis-induced infection. 相似文献
36.
Albrecht MT Li H Williamson ED LeButt CS Flick-Smith HC Quinn CP Westra H Galloway D Mateczun A Goldman S Groen H Baillie LW 《Infection and immunity》2007,75(11):5425-5433
The unpredictable nature of bioterrorism and the absence of real-time detection systems have highlighted the need for an efficient postexposure therapy for Bacillus anthracis infection. One approach is passive immunization through the administration of antibodies that mitigate the biological action of anthrax toxin. We isolated and characterized two protective fully human monoclonal antibodies with specificity for protective antigen (PA) and lethal factor (LF). These antibodies, designated IQNPA (anti-PA) and IQNLF (anti-LF), were developed as hybridomas from individuals immunized with licensed anthrax vaccine. The effective concentration of IQNPA that neutralized 50% of the toxin in anthrax toxin neutralization assays was 0.3 nM, while 0.1 nM IQNLF neutralized the same amount of toxin. When combined, the antibodies had additive neutralization efficacy. IQNPA binds to domain IV of PA containing the host cell receptor binding site, while IQNLF recognizes domain I containing the PA binding region in LF. A single 180-mug dose of either antibody given to A/J mice 2.5 h before challenge conferred 100% protection against a lethal intraperitoneal spore challenge with 24 50% lethal doses [LD50s] of B. anthracis Sterne and against rechallenge on day 20 with a more aggressive challenge dose of 41 LD50s. Mice treated with either antibody and infected with B. anthracis Sterne developed detectable murine anti-PA and anti-LF immunoglobulin G antibody responses by day 17 that were dependent on which antibody the mice had received. Based on these results, IQNPA and IQNLF act independently during prophylactic anthrax treatment and do not interfere with the establishment of endogenous immunity. 相似文献
37.
38.
39.
Presented are results of a study of the application of linear quadratic optimal model-following control applied to a Bell 205 helicopter in hover. The primary objective of good in-flight stability robustness and performance was accomplished via singular value analysis using perturbed systems. Nominal aircraft models were compared with experimental data and discrepancies quantified in a robustness criterion. Current military handling quality requirements were specified as a target model to be followed. The linear quadratic optimal control and command feedforward was found suitable for these requirements. Design analyses enabled consideration of the tuning process, where effects of variations in selected tuning parameters demonstrated their sensitivity to the design. 相似文献
40.
目的探讨腹腔镜外科技术在胃肠道肿瘤手术中的应用。方法经电视腹腔镜行胃肠道肿瘤手术18例,其中右半结肠切除术4例,横结肠癌根治术3例,乙状结肠癌根治术5例,乙状结肠癌姑息切除术并肝转移癌电凝固化1例,胃癌术后复发转移行探查活检1例,胃巨大恶性淋巴瘤行探查活检1例,晚期回肠癌行小肠侧侧吻合术1例,乙状结肠腺瘤切除术2例。结果均获成功,无中转开腹,手术时间平均165.0分钟。术后平均31.2小时胃肠功能恢复,无并发症发生,术后平均住院8.2天。13例切除肿瘤的结肠癌术后随访2月~30月,仅1例横结肠癌术后23月出现肺转移。结论腹腔镜胃肠肿瘤手术损伤小、恢复快、胃肠干扰小、术后疼痛轻,值得进一步探索开展。 相似文献