全文获取类型
收费全文 | 567篇 |
免费 | 20篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 15篇 |
妇产科学 | 4篇 |
基础医学 | 44篇 |
口腔科学 | 29篇 |
临床医学 | 27篇 |
内科学 | 145篇 |
皮肤病学 | 1篇 |
神经病学 | 27篇 |
特种医学 | 95篇 |
外科学 | 41篇 |
综合类 | 23篇 |
预防医学 | 69篇 |
眼科学 | 3篇 |
药学 | 32篇 |
肿瘤学 | 35篇 |
出版年
2022年 | 6篇 |
2021年 | 14篇 |
2020年 | 11篇 |
2019年 | 9篇 |
2018年 | 11篇 |
2017年 | 7篇 |
2016年 | 10篇 |
2015年 | 14篇 |
2014年 | 10篇 |
2013年 | 24篇 |
2012年 | 26篇 |
2011年 | 23篇 |
2010年 | 23篇 |
2009年 | 16篇 |
2008年 | 26篇 |
2007年 | 26篇 |
2006年 | 15篇 |
2005年 | 15篇 |
2004年 | 25篇 |
2003年 | 14篇 |
2002年 | 13篇 |
2001年 | 10篇 |
2000年 | 9篇 |
1999年 | 9篇 |
1998年 | 20篇 |
1997年 | 21篇 |
1996年 | 16篇 |
1995年 | 16篇 |
1994年 | 16篇 |
1993年 | 10篇 |
1992年 | 5篇 |
1991年 | 7篇 |
1990年 | 9篇 |
1989年 | 10篇 |
1988年 | 7篇 |
1987年 | 5篇 |
1986年 | 7篇 |
1985年 | 5篇 |
1984年 | 6篇 |
1982年 | 3篇 |
1981年 | 6篇 |
1980年 | 10篇 |
1979年 | 3篇 |
1978年 | 7篇 |
1977年 | 7篇 |
1976年 | 5篇 |
1975年 | 5篇 |
1972年 | 3篇 |
1954年 | 2篇 |
1953年 | 2篇 |
排序方式: 共有591条查询结果,搜索用时 203 毫秒
1.
E M Guerra A J Vaz L A de Toledo S A Ianoni C M Quadros R M Dias O C Barretto 《Revista do Instituto de Medicina Tropical de S?o Paulo》1991,33(4):303-308
481 pregnant women attended at first consultation from a S?o Paulo city suburb-subdistrict of Butantan-S?o Paulo State, Brazil, from April to October of 1988, were investigated regarding the prevalence of verminosis. The mean age was 24.5 years (range 14-46), the average family income was 0.97 PCMW (per capita minimum wage) and the average number of members of the family was 4 (1 to 15). The verminosis prevalence was 45.1% among the women. The most frequent parasites were: Ascaris lumbricoides (19.0%), ancilostomídeos (16.7%) and Trichuris trichiura (15.9%). The verminosis prevalence was significantly higher among the pregnant women (p < 0.05) who belonged to the families with income below 0.5 PCMW and greater than 4 members. 相似文献
2.
3.
4.
The case for global eradication of poliomyelitis 总被引:2,自引:0,他引:2
A R Hinman W H Foege C A de Quadros P A Patriarca W A Orenstein E W Brink 《Bulletin of the World Health Organization》1987,65(6):835-840
Global eradication of poliomyelitis can be achieved by a programme strategy that includes achievement and maintenance of high immunization levels, effective surveillance to detect all new cases, and a rapid vigorous response to the occurrence of new cases. Regional eradication targets have already been set in Europe and the Americas. Possible impediments to eradication include the necessity to generate political and social will; managerial constraints; issues of vaccine efficacy, stability, and cost; and adequacy of surveillance. We believe that the impediments can be overcome and that with intensified effort and increased international collaboration, global eradication could be achieved as early as 1995. 相似文献
5.
6.
Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
7.
Can energy drinks reduce the depressor effect of ethanol? An experimental study in mice 总被引:3,自引:0,他引:3
Ferreira SE Hartmann Quadros IM Trindade AA Takahashi S Koyama RG Souza-Formigoni ML 《Physiology & behavior》2004,82(5):841-847
Although the popularization of the combined use of alcoholic beverages and energy drinks (ED) containing caffeine, taurine and other substances has increased, there are no controlled experimental studies on the effects of ED alone or combined with ethanol. This work aimed at evaluating the effects of different doses of ED combined or not with ethanol, on the locomotor activity of Swiss mice. The administration of 3.57, 10.71 or 17.86 ml/kg of ED alone increased the locomotor activity of the animals in relation to a control group. Low doses of ethanol (0.5, 1.0 and 1.5 g/kg) alone or in combination with 10.71 ml/kg of ED did not affect their locomotor activity. However, the reduction of activity observed after 2.5 g/kg of ethanol was antagonized by 10.71 ml/kg of ED. Further studies on the mechanisms of this interaction are still needed. 相似文献
8.
In a child with some features of Turner's syndrome, gonosomal mosaicism with an isodicentric nonfluorescent (idic)Y chromosome was detected (mos 45,X/47,X,idic(Y)(q11),idic(Y)(11)/46,X,idic(Y)(q11)). Histopathological examination showed streak gonads with some evidence of ovarian stroma and no sign of gonadoblastoma. Polymerase chain reaction (PCR) analysis in blood lymphocytes and gonadal tissues using primers of seven loci along the Y chromosome, including the sex determined region (SRY), azoospermia factor region (AZF) and the deleted in azoospermia ( DAZ ) gene was positive for all loci tested, confirming the isodicentric character of the Y chromosome and indicating the presence of the AZF region. It is remarkable that the existence of spermatogenesis controlling genes does not play an important role in gonadal development and differentiation in a phenotypic female with some Turner stigmata. The data presented here are briefly discussed with previously-described patients. 相似文献
9.
Jordan C. Best BS Taylor Kohn MD Premal Patel MD Ruben Blachman-Braun MD Elaine de Quadros PhD Zeki Beyhan PhD Michael Jacobs MD Ranjith Ramasamy MD 《Andrologia》2021,53(7):e14094
In this study, we sought to determine whether sperm DNA fragmentation (DFI%) and high DNA stainability (HDS%) evaluated by sperm chromatin structure assay (SCSA) predict recurrent implantation failure (RIF) or pregnancy rate. A retrospective study was performed of consecutive cycles of ICSI treatment from 2009 to 2018. A total of 386 couples that underwent 1,216 frozen embryo transfer (FET) cycles were analysed. Mean female and male age was 34 ± 3.6 years and 37.3 ± 6.6 years, respectively, and a median total motile sperm count (TMSC) was 43.5 [9.9–105.5] million. Overall median DFI% and HDS% was 12 [7.1–18.9] and 9.6 [6.5–14.4] respectively. On multivariable analysis, DFI% and HDS% were not associated with RIF (DFI%: OR = 1.01, 95% CI: 0.98–1.04, p = .414; HDS%: OR = 0.97, 95% CI: 0.94–1.01, p = .107) or IVF success, defined as clinical pregnancy (DFI%: OR = 1.00, 95% CI: 0.99–1.01, p = .641; HDS%: OR = 1.01, 95% CI: 0.99–1.02, p = .565). We found that neither DFI% or HDS%, as assessed by SCSA, were predictive of RIF or pregnancy rate. This finding suggests that sperm DNA fragmentation does not predict RIF or pregnancy rate. 相似文献
10.
Renal transplant (RT) is now a therapy of choice for end stage renal disease (ESRD). The Nephrology Unit, Asvini started functioning in Dec 90 and to date 1298 sittings of hemodialysis have been given to 45 patients. Of these, 35 were in ESRD and 11 patients underwent renal transplantation at this hospital during the period Jan 91 – Dec 93. One patient expired after 18 months of transplantation due to infection. Early experience in screening patients for RT, use of immunosuppression, management of rejection episodes and protocol are presented with special emphasis on its relevance to the Armed Forces.KEY WORDS: Transplantation, Renal Failure, Immunosuppression, Rejection 相似文献