全文获取类型
收费全文 | 935篇 |
免费 | 75篇 |
国内免费 | 20篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 36篇 |
妇产科学 | 11篇 |
基础医学 | 154篇 |
口腔科学 | 26篇 |
临床医学 | 161篇 |
内科学 | 231篇 |
皮肤病学 | 3篇 |
神经病学 | 46篇 |
特种医学 | 157篇 |
外科学 | 46篇 |
综合类 | 30篇 |
预防医学 | 52篇 |
眼科学 | 4篇 |
药学 | 33篇 |
肿瘤学 | 38篇 |
出版年
2023年 | 7篇 |
2022年 | 7篇 |
2021年 | 11篇 |
2020年 | 3篇 |
2019年 | 5篇 |
2018年 | 5篇 |
2017年 | 6篇 |
2016年 | 10篇 |
2015年 | 6篇 |
2014年 | 22篇 |
2013年 | 31篇 |
2012年 | 15篇 |
2011年 | 23篇 |
2010年 | 29篇 |
2009年 | 49篇 |
2008年 | 26篇 |
2007年 | 29篇 |
2006年 | 23篇 |
2005年 | 31篇 |
2004年 | 23篇 |
2003年 | 27篇 |
2002年 | 31篇 |
2001年 | 28篇 |
2000年 | 30篇 |
1999年 | 26篇 |
1998年 | 47篇 |
1997年 | 47篇 |
1996年 | 43篇 |
1995年 | 35篇 |
1994年 | 23篇 |
1993年 | 27篇 |
1992年 | 25篇 |
1991年 | 12篇 |
1990年 | 17篇 |
1989年 | 33篇 |
1988年 | 31篇 |
1987年 | 29篇 |
1986年 | 11篇 |
1985年 | 26篇 |
1984年 | 14篇 |
1983年 | 9篇 |
1982年 | 20篇 |
1981年 | 15篇 |
1980年 | 19篇 |
1979年 | 7篇 |
1978年 | 11篇 |
1977年 | 13篇 |
1976年 | 7篇 |
1975年 | 2篇 |
1973年 | 2篇 |
排序方式: 共有1030条查询结果,搜索用时 0 毫秒
1.
2.
3.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
4.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
5.
表小檗碱对α受体的作用 总被引:2,自引:0,他引:2
表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择 相似文献
6.
The purpose of this pilot study was to observe both relaxed and deep breathing patterns in a convenience sample to determine the incidence of normal versus faulty patterns of respiration. These observations were then combined with respondent answers to a survey on pain history to determine if there is any correlation between faulty breathing and musculo-skeletal pain patterns. If such a correlation can be made, then we propose that clinicians working with chronic pain patients may have improved outcomes if they address and correct faulty breathing patterns. Based on this study, it is suggested to include the evaluation and treatment of faulty respiration in the rehabilitation of chronic musculo-skeletal conditions, most notably cervical pain. 相似文献
7.
36例踝关节骨折合并下胫腓联合分离的治疗体会 总被引:1,自引:1,他引:0
0 引言 踝关节骨折是临床上较常见的关节内骨折,包含了腓骨骨折,内踝骨折,后踝骨折和下胫腓联合的损伤. 处理不当可导致踝穴的变形,下胫腓联合分离后期出现创伤性关节炎. 相似文献
8.
A novel malaria protein, Pfs28, and Pfs25 are genetically linked and synergistic as falciparum malaria transmission-blocking vaccines. 总被引:11,自引:5,他引:6
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Antibodies to Pfs28 block Plasmodium falciparum transmission and when combined with antibodies to Pfs25 provide synergy in blocking transmission. Pfs28 and Pfs25 are immunogenic, have limited antigenic diversity, and are structurally similar and genetically linked on chromosome 10. Pfs28 may prove a useful addition to Pfs25 in an effective transmission-blocking vaccine. 相似文献
9.
Natural immune response to the C-terminal 19-kilodalton domain of Plasmodium falciparum merozoite surface protein 1. 总被引:5,自引:2,他引:5
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Y P Shi U Sayed S H Qari J M Roberts V Udhayakumar A J Oloo W A Hawley D C Kaslow B L Nahlen A A Lal 《Infection and immunity》1996,64(7):2716-2723
We have characterized the natural immune responses to the 19-kDa domain of merozoite surface protein 1 in individuals from an area of western Kenya in which malaria is holoendemic. We used the three known natural variant forms of the yeast-expressed recombinant 19-kDa fragment that are referred to as the E-KNG, Q-KNG, and E-TSR antigens. T-cell proliferative responses in individuals older than 15 years and the profile of immunoglobulin G (IgG) antibody isotypes in individuals from 2 to 74 years old were determined. Positive proliferative responses to the Q-KNG antigen were observed for 54% of the individuals, and 37 and 35% of the individuals responded to the E-KNG and E-TSR constructs, respectively. Considerable heterogeneity in the T-cell proliferative responses to these three variant antigens was observed in different individuals, suggesting that the 19-kDa antigen may contain variant-specific T epitopes. Among responses of the different isotypes of the IgG antibody, IgG1 and IgG3 isotype responses were predominant, and the prevalence and levels of the responses increased with age. We also found that a higher level of IgG1 antibody response correlated with lower parasite density among young age groups, suggesting that IgG1 antibody response may play a role in protection against malaria. However, there was no correlation between the IgG3 antibody level and protection. Furthermore, we observed that although the natural antibodies cross-reacted with all three variant 19-kDa antigens, IgG3 antibodies in 12 plasma samples recognized only the E-KNG and Q-KNG constructs and not the E-TSR antigen. This result suggests that the fine specificity of IgG3 antibodies differentiates among variant-specific natural B-cell determinants in the second epidermal growth factor domain (KNG and TSR) of the antigen. 相似文献
10.
Abstract: Polymorphisms in genes encoding transporters associated with antigen processing (TAP) have been associated with heterogeneity of disease progression in HTV-l-infected homosexual men. In our recent AIDS-related studies of cohorts from Rwanda and Zambia, four new polymorphic sites in the TAP2 coding region were detected by single-strand conformation polymorphism (SSCP) and confirmed by bi-directional nucleotide sequencing and restriction enzyme digestion. The first, a substitution of Thr (GCC) for Ala (ACC) at codon position 374 in exon 5, was found in about 13% of Rwandans and Zambians ( n =213). The remaining 3 new polymorphisms were seen in the 7th exon with changes of 458Thr-ACG to ACA, 466Gly-GGG to GGA, and 467Val-GTT to Ile-ATT, respectively. These 3 variants occurred exclusively on the same chromosome and appeared to have arisen together from the 374Thr-bearing allele. Analyses of the relationship between the 374Thr-457Ile segment and the nearby markers in DQB1 and DRB1 suggested the existence of a unique extended haplotype related to these newly identified variants. 相似文献