全文获取类型
收费全文 | 538篇 |
免费 | 27篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 8篇 |
基础医学 | 60篇 |
口腔科学 | 2篇 |
临床医学 | 14篇 |
内科学 | 184篇 |
皮肤病学 | 9篇 |
神经病学 | 1篇 |
特种医学 | 3篇 |
外科学 | 31篇 |
综合类 | 74篇 |
预防医学 | 136篇 |
眼科学 | 3篇 |
药学 | 29篇 |
中国医学 | 9篇 |
肿瘤学 | 11篇 |
出版年
2023年 | 11篇 |
2022年 | 6篇 |
2021年 | 12篇 |
2020年 | 10篇 |
2019年 | 8篇 |
2018年 | 5篇 |
2017年 | 16篇 |
2016年 | 12篇 |
2015年 | 15篇 |
2014年 | 30篇 |
2013年 | 39篇 |
2012年 | 36篇 |
2011年 | 37篇 |
2010年 | 23篇 |
2009年 | 39篇 |
2008年 | 22篇 |
2007年 | 26篇 |
2006年 | 20篇 |
2005年 | 23篇 |
2004年 | 18篇 |
2003年 | 28篇 |
2002年 | 9篇 |
2001年 | 8篇 |
2000年 | 9篇 |
1999年 | 10篇 |
1998年 | 7篇 |
1997年 | 10篇 |
1996年 | 17篇 |
1995年 | 5篇 |
1994年 | 7篇 |
1993年 | 8篇 |
1992年 | 9篇 |
1991年 | 3篇 |
1990年 | 9篇 |
1989年 | 4篇 |
1988年 | 8篇 |
1987年 | 7篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1983年 | 2篇 |
排序方式: 共有575条查询结果,搜索用时 15 毫秒
1.
本文应用 Mop-Videoplan 图象分析仪对氟中毒家猪胫骨进行了骨计量学的初步研究。四环素双标记后将家猪胫骨制备成骨磨片,在荧光及普通光学显微镜下测量了一系列骨计量学参数。结果表明,氟中毒导致家猪胫骨髓腔面皮质新骨体积明显增加,但其增加程度不与血氟呈正相关。新骨体积增加可能是造成临床 X 线氟骨症表现骨髓腔狭窄的原因。骨动力学研完表明,氟中毒造成四环素双标记明显减少,这可能与氟抑制骨组织的转换过程有关。 相似文献
2.
<正>在碘缺乏病区,居民甲状腺肿患病率在年鹅分布上的特征,可用二次抛物线加以描述[l].根握资料类型的不同,可选择更为适合的三次抛物线来描述.根据现场调查资料,本文采用三次抛物线方法进行配合,并将配合结果与二 相似文献
3.
西部开发中的虫媒病传播问题 总被引:1,自引:1,他引:1
陆宝麟 《寄生虫与医学昆虫学报》2003,10(4):212-217
西部开发地区存在许多虫媒病 ,即昆虫和蜱螨传播的疾病 ,为了保障开发人群的健康 ,首先需要对这些疾病的传播 ,特别是有些疾病的自然疫源地或流行区有所了解。本文列述了 13种虫媒病及其在这个地区的分布 ,对其中值得我们更重视的 4类重要疾病 ,包括鼠疫、莱姆病、疟疾和登革热的病原体传播媒介或有的贮存宿主以及重要性等作了扼要的介绍。本文并提出了这类疾病在开发中和开发后可能产生的危害性 ,以及防止或减少它们危害的建议。作者认为从开发地区的长远利益出发 ,应该重视开发中自然环境改变对上述虫媒病传播影响的研究 相似文献
4.
Study of induction of activation of human peripheral blood mononuclear cells with a non-activating form of anti-CD3 MoAb in autoimmune thyroid disease (AITD). 下载免费PDF全文
E Resetkova G Arreaza N Yoshikawa T Morita H Kim P Carayon R Volp 《Clinical and experimental immunology》1993,91(3):397-403
Anti-CD3 (OKT3) MoAb is a mitogenic agent which activates lymphocytes. We have studied the effects of murine anti-human OKT3 MoAb (IgG1) alone or in combination with IL-2, human thyroglobulin (Tg) and thyroperoxidase (TPO) antigens on the proliferation of whole peripheral blood mononuclear cells (PBMC) (including monocytes) or subtypes (T, CD4+, CD8+, B) as measured by tritiated thymidine (3H-TdR) incorporation. B cell differentiation was studied by measuring numbers of IgG-secreting cells and specific anti-TPO/anti-Tg-secreting cells by SPOT ELISA. PBMC or lymphocyte subtypes, obtained from 45 patients with Hashimoto's thyroiditis (HT), 40 Graves' disease (GD) and 51 normal controls were cultured in 96 microtitre plates for 6 days in the presence of OKT3 MoAb at final concentrations 25-250 ng/ml, IL-2 15 U/ml, Tg and TPO (1 micrograms/ml). Then cultures were pulsed with 0.2 microCi 3H-TdR/well and incorporation was measured after 18 h. IgG and anti-TPO/Tg-secreting cells were detected at 7 days. Higher proliferative responses from whole PBMC preparations in response to any of the combinations including OKT3 MoAb were observed in the HT preparations, while the basal values were the lowest. IL-2 alone increased these responses markedly, but equally in all groups. IL-2 in combination with OKT3 had an additive effect on proliferation, with higher responses in HT. Tg and TPO antigens did not change these responses. Most HT preparations responded with their maximum proliferation to the lowest concentration of OKT3 MoAb (25 ng/ml), whereas in GD and control preparations of PBMC these responses were shifted to higher concentrations (250 ng/ml); even with those, proliferation was not so enhanced in controls when compared with HT and GD preparations. In contrast, the proliferative responses of T cells alone and subpopulations of CD8+ suppressor/cytotoxic cells were decreased in HT preparations compared with controls. Monocytes were necessary for proliferation. In the subpopulation of B cells (> 95% pure) and CD4+ helper/inducer cells, differences did not reach significance. In spite of the effect on proliferation, OKT3 MoAb only mildly but significantly increased the numbers of IgG-secreting cells in HT and GD preparations and did not stimulate synthesis of specific antibodies. Our data suggest that the increased proliferative responses of whole PBMC to OKT3 MoAb in HT preparations might be due to insufficient activation of T suppressor/cytotoxic cells. 相似文献
5.
Hironobu Tawaraya Showgo Ohkoshi Kenji Kuwana Masashi Watanabe Tomoteru Kamimura And Hitoshi Asakura 《Journal of medical virology》1995,45(4):367-372
Mass screening for hepatitis C virus antibody was carried out in 875 inhabitants (313 men and 562 women) of a town in Japan with a high rate of hepatitis B virus infection. The overall rate of positivity for anti-HCV was 8.8% (6.4% in men and 10,1% in women). The rate of positivity for hepatitis B virus surface antigen was 11.2%. Five subjects (0.6%) were positive for both markers. HCV-RNA was detected in 65 (88.4%) of 77 individuals who were positive for anti-HCV and in 1 (1.5%) of 60 individuals negative for anti-HCV. The genotype of the HCV genome was determined by PCR analysis using type-specific primers in 60 individuals. HCV type 1b was detected in 51 subjects (85%), type 2a in 3 subjects (5%), and type 2b in 6 subjects (10%). None of the individuals was infected with more than one genotype. The nucleotide sequences of the partial nonstructural 5 region of HCV type 1b genotype obtained from 6 individuals showed at least 92.0% homology in the nucleotide sequence, and 94.8% homology in the amino acid sequence. Homology among these clones was greater than their homology with previously described type 1 b sequences. The findings suggest that there was a specific local origin of HCV infection, although it was not possible to identify any single source of HCV infection. The results also indicate the presence of asymptomatic HCV carriers. © 1995 Wiley-Liss, Inc. 相似文献
6.
Molecular epidemiological and clinical aspects of hepatitis D virus in a unique triple hepatitis viruses (B,C, D) endemic community in Taiwan 总被引:2,自引:0,他引:2
The molecular epidemiological and clinical aspects of hepatitis D virus (HDV) in a unique HBV, HCV, and HDV triple virus endemic community in southern Taiwan were investigated. A total of 2,909 residents aged 45 or older were screened for hepatitis B surface antigen (HBsAg), anti-HCV antibody, and anti-HDV antibody (specifically for HBsAg-positive carriers). Factors that might be associated with HDV infection, viral nucleic acid detection, and genotyping of HBV, HCV, and HDV were investigated. The prevalence of HBsAg and anti-HCV were 12.6% (366/2,909) and 41.6% (1,227/2,909), respectively. For HBsAg carriers, 15.3% (56/366) were positive for anti-HDV assay. Living in a higher endemic district of HCV infection (odds ratio [OR] = 3.2; 95% confidence interval [CI] = 1.7-6.3), male gender (OR = 1.9; 95% CI = 1.1-3.6) and co-infection with HCV (OR = 1.8; 95% CI = 1.0-3.3) were significantly independent factors associated with HDV infection. The detection rate of HDV RNA among anti-HDV-positive patients was only 12.7% (7/55). The mean HBV titer of triple infection group was significantly lower than in the HBV/HDV co-infection group (2.23 vs 3.05 in log(10), copies/ml, P = 0.046). HCV RNA detection among the triple infection group showed 47.4% (9/19) viremia rate and viral loads of 579,121 IU/ml in median (16,803-1,551,190 IU/ml). The prevalent genotype of HBV was type B (23/25); HCV was 1b (7/9) and HDV was IIa/IIb (4/4). Only the presence of HCV RNA predicted the presence of elevated ALT significantly (OR = 25.0; 95% CI = 3.39-184.6). In conclusion, the geographical aggregation of HDV infection paralleled that of HCV infection in this community. HCV suppressed the replication of HBV among triple vital infection patients. HBV and HDV lapsed into a remission or nonreplicative phase in most cases, and HCV acted as a dominant factor in triple viral-infected individuals. Only the presence of HCV RNA was associated with elevated ALT values, but not HBV or HDV. 相似文献
7.
Jos María Robaina-Bordn Cristina Carranza-Rodríguez Michele Hernndez-Cabrera Margarita Bolaos-Rivero Elena Pisos-lamo Nieves Jan-Snchez Araceli Hernndez-Betancor Laura Surez-Hormiga Jos Luis Prez-Arellano 《Emerging infectious diseases》2021,27(2):570
To document the epidemiology, clinical features, and outcomes of murine typhus patients in the Canary Islands (Spain), we analyzed data that were retrospectively collected for 16 years for 221 patients. Murine typhus in the Canary Islands is characterized by a high rate of complications (31.6%), mainly liver, lung, kidney or central nervous system involvement. 相似文献
8.
9.
Lulan Wang Jingzhe Shang Shenghui Weng Saba R. Aliyari Chengyang Ji Genhong Cheng Aiping Wu 《Journal of medical virology》2023,95(1):e28036
Monkeypox virus (MPXV) has generally circulated in West and Central Africa since its emergence. Recently, sporadic MPXV infections in several nonendemic countries have attracted widespread attention. Here, we conducted a systematic analysis of the recent outbreak of MPXV-2022, including its genomic annotation and molecular evolution. The phylogenetic analysis indicated that the MPXV-2022 strains belong to the same lineage of the MPXV strain isolated in 2018. However, compared with the MPXV strain in 2018, in total 46 new consensus mutations were observed in the MPXV-2022 strains, including 24 nonsynonymous mutations. By assigning mutations to 187 proteins encoded by the MPXV genome, we found that 10 proteins in the MPXV are more prone to mutation, including D2L-like, OPG023, OPG047, OPG071, OPG105, OPG109, A27L-like, OPG153, OPG188, and OPG210 proteins. In the MPXV-2022 strains, four and three nucleotide substitutions are observed in OPG105 and OPG210, respectively. Overall, our studies illustrated the genome evolution of the ongoing MPXV outbreak and pointed out novel mutations as a reference for further studies. 相似文献
10.
通过对丹江口市饮水型型地氟病区两个村改水前后环境氟含量,人体总摄氟量及8-12岁儿童氟玉牙发病率的调查与相关分析,发现改水后人群总摄氟量中食中氟所占比例约为40%-50%,总摄氟量与8-12岁儿童氟斑牙率,氟斑牙指数,尿氟均呈正相关,总一比单纯水氟或粮食氟更能反映出人群总体氟水平。 相似文献