全文获取类型
收费全文 | 11796篇 |
免费 | 932篇 |
国内免费 | 36篇 |
专业分类
耳鼻咽喉 | 130篇 |
儿科学 | 347篇 |
妇产科学 | 295篇 |
基础医学 | 1575篇 |
口腔科学 | 410篇 |
临床医学 | 1365篇 |
内科学 | 2188篇 |
皮肤病学 | 121篇 |
神经病学 | 975篇 |
特种医学 | 592篇 |
外国民族医学 | 1篇 |
外科学 | 1966篇 |
综合类 | 167篇 |
一般理论 | 7篇 |
预防医学 | 1082篇 |
眼科学 | 270篇 |
药学 | 521篇 |
中国医学 | 9篇 |
肿瘤学 | 743篇 |
出版年
2021年 | 155篇 |
2020年 | 95篇 |
2019年 | 135篇 |
2018年 | 173篇 |
2017年 | 144篇 |
2016年 | 150篇 |
2015年 | 201篇 |
2014年 | 279篇 |
2013年 | 371篇 |
2012年 | 509篇 |
2011年 | 508篇 |
2010年 | 333篇 |
2009年 | 292篇 |
2008年 | 459篇 |
2007年 | 544篇 |
2006年 | 507篇 |
2005年 | 408篇 |
2004年 | 459篇 |
2003年 | 458篇 |
2002年 | 441篇 |
2001年 | 401篇 |
2000年 | 422篇 |
1999年 | 371篇 |
1998年 | 153篇 |
1997年 | 143篇 |
1996年 | 160篇 |
1995年 | 124篇 |
1994年 | 132篇 |
1993年 | 113篇 |
1992年 | 289篇 |
1991年 | 278篇 |
1990年 | 259篇 |
1989年 | 268篇 |
1988年 | 225篇 |
1987年 | 224篇 |
1986年 | 245篇 |
1985年 | 255篇 |
1984年 | 205篇 |
1983年 | 135篇 |
1982年 | 93篇 |
1981年 | 90篇 |
1979年 | 162篇 |
1978年 | 105篇 |
1977年 | 101篇 |
1976年 | 100篇 |
1975年 | 88篇 |
1974年 | 103篇 |
1972年 | 100篇 |
1971年 | 81篇 |
1970年 | 77篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
83.
Johannes W. G. Jacobs MD PhD Agnes van der Heide MD Johannes J. Rasker MD PhD Johannes W. J. Bijlsma MD PhD 《Patient education and counseling》1993,20(2-3):121-132
Chronic arthritis may have great impact on the patient but also on his or her family, relatives and friends. The assessment of the consequences of chronic arthritis and the effect of therapy not only in terms of physical, but also psychological and social dimensions deserves more attention. Functional ability and health status can be measured using a questionnaire or ‘instrument’, high-lighting important aspects not quantified with more traditional measurements. In this paper, arguments to apply such instruments more frequently are given. Health status instruments can be used not only to assess beneficial but also deleterious (side-)effects of therapeutic interventions. The properties are summarized of the most frequently used instruments assessing functional ability and health status. Many of these instruments have been evaluated sufficiently for validity and reliability; their sensitivity to detect change seems to be satisfactory. Therefore it is advisable to choose an internationally accepted, frequently used instrument, reflecting the area of interest. 相似文献
84.
Conserved tRNA gene cluster in starfish mitochondrial DNA 总被引:10,自引:0,他引:10
Howard T. Jacobs Shuichi Asakawa Takeyoshi Araki Kin-ichiro Miura Michael J. Smith Kimitsuna Watanabe 《Current genetics》1989,15(3):193-206
Summary Partial sequencing of mtDNA from four long-diverged species of starfish reveals the existence of a conserved cluster of 13 tRNA genes, organized in a manner similar to that of the tRNA cluster of sea urchin mtDNA, but located at a position distant from the presumed replication origin. These findings suggest that a clustered organization of tRNA genes may have been present in the ancestral mitochondrial genome, and raise the possibility that tRNAs may have catalyzed the dispersal rather than the accumulation of the genes which encode them. 相似文献
85.
Male wild (Cavia aperea) and domestic (C. porcellus) guinea pigs were tested in two-bottle choice tests for preferences between glucose solutions of different concentrations and de-ionized water. Wild males showed significant preferences for concentrations between 0.025 and 0.4 M glucose while domestic males preferred only the 0.2 M glucose solution to de-ionized water. C. aperea males also consumed significantly greater volumes of liquid per kg body during the glucose tests than did the C. porcellus males. These comparative results contrast sharply with those obtained by other authors with wild and domestic Norway rats. 相似文献
86.
87.
Hyperoxygenation effect on cognitive functioning in the aged 总被引:1,自引:0,他引:1
88.
Metabolic adaptation of the chick embryo to chronic hypoxia 总被引:1,自引:0,他引:1
89.
Use of immunoglobulin coupled to agarose beads for examining the specificity of conjugates. 下载免费PDF全文
Preparations of purified immunoglobulins, light chains, and unrelated proteins (used as controls) were covalently linked to agarose beads and used to study the specificity of fluorescein isothiocyanate conjugates. The data demonstrate how these beads can be used to detect immunological and non-immunological reactivity in conjugates. Commercial conjugates, conjugates prepared in this laboratory, and fluorescein-labeled normal immunoglobulins demonstrated high reactivity with control beads unless chromatographed on diethylaminoethyl-cellulose to select for the proper fluorescein-protein ratio. Undesirable immunological reactivity could be demonstrated in commercial conjugates and was shown to be due to anti-light-chain antibody. 相似文献
90.
Miscarriage rates following in-vitro fertilization are increased in women with polycystic ovaries and reduced by pituitary desensitization with buserelin 总被引:3,自引:10,他引:3
Balen Adam H.; Tan Seang-Lin; MacDougall Jane; Jacobs Howard S. 《Human reproduction (Oxford, England)》1993,8(6):959-964
To assess the risk of miscarriage after in-vitro fertilization(IVF) with respect to age, cause of infertility, ovarian morphologyand treatment regimen, a retrospective analysis was performedof the first 1060 pregnancies conceived between June 1984 andJuly 1990 as a result of 7623 IVF cycles. Superovulation inductionwas achieved with human menopausal gonadotrophin (HMG) and/orpurified follicle stimulating hormone (FSH) together with eitherclomiphene citrate or the gonadotrophin hormone-releasing hormone(GnRH) agonist buserelin, the latter either as a short flareregimen or as a long regimen to induce pituitarydesensitization. There were 282 spontaneous abortions (26.6%)and 54 ectopic pregnancies (5.1%). The mean age of women withongoing pregnancies was 32.2 (SD 3.9) years compared with 33.2(SD 4.1) years in those who miscarried, which were significantlydifferent (P = 0.008). There was no relation between the miscarriagerate and the indication for IVF. The miscarriage rate was 23.6%in women with normal ovaries compared with 35.8% in those withpolycystic ovaries [P = 0.0038, 95% confidence interval (CI)4.6823.10%]. There was no difference in the miscarriagerate between treatment with HMG or FSH. Women whose ovarieswere normal on ultrasound were just as likely to miscarry ifthey were treated with clomiphene or with the long buserelinprotocol. Those with polycystic ovaries, however, had a significantreduction in the rate of miscarriage when treated with the longbuserelin protocol, 20.3% (15/74), compared with clomiphenecitrate, 47.2% (51/108) (P = 0.0003, 95% CI 13.8240.09%). 相似文献