全文获取类型
收费全文 | 1503篇 |
免费 | 178篇 |
国内免费 | 28篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 143篇 |
妇产科学 | 24篇 |
基础医学 | 203篇 |
口腔科学 | 90篇 |
临床医学 | 159篇 |
内科学 | 282篇 |
皮肤病学 | 49篇 |
神经病学 | 34篇 |
特种医学 | 173篇 |
外科学 | 223篇 |
综合类 | 38篇 |
预防医学 | 97篇 |
眼科学 | 40篇 |
药学 | 53篇 |
中国医学 | 2篇 |
肿瘤学 | 93篇 |
出版年
2023年 | 14篇 |
2022年 | 11篇 |
2021年 | 15篇 |
2020年 | 16篇 |
2019年 | 7篇 |
2018年 | 45篇 |
2017年 | 46篇 |
2016年 | 41篇 |
2015年 | 60篇 |
2014年 | 76篇 |
2013年 | 106篇 |
2012年 | 46篇 |
2011年 | 29篇 |
2010年 | 77篇 |
2009年 | 92篇 |
2008年 | 31篇 |
2007年 | 48篇 |
2006年 | 47篇 |
2005年 | 27篇 |
2004年 | 28篇 |
2003年 | 13篇 |
2002年 | 20篇 |
2001年 | 15篇 |
2000年 | 9篇 |
1999年 | 24篇 |
1998年 | 101篇 |
1997年 | 86篇 |
1996年 | 98篇 |
1995年 | 63篇 |
1994年 | 74篇 |
1993年 | 39篇 |
1992年 | 14篇 |
1991年 | 21篇 |
1990年 | 13篇 |
1989年 | 31篇 |
1988年 | 29篇 |
1987年 | 28篇 |
1986年 | 26篇 |
1985年 | 24篇 |
1984年 | 12篇 |
1983年 | 9篇 |
1982年 | 20篇 |
1981年 | 15篇 |
1980年 | 16篇 |
1979年 | 5篇 |
1978年 | 6篇 |
1977年 | 9篇 |
1976年 | 13篇 |
1975年 | 9篇 |
1966年 | 1篇 |
排序方式: 共有1709条查询结果,搜索用时 15 毫秒
21.
22.
23.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献
24.
Localization of a gene for otosclerosis to chromosome 15q25-q26 总被引:5,自引:0,他引:5
Tomek MS; Brown MR; Mani SR; Ramesh A; Srisailapathy CR; Coucke P; Zbar RI; Bell AM; McGuirt WT; Fukushima K; Willems PJ; Van Camp G; Smith RJ 《Human molecular genetics》1998,7(2):285-290
Among white adults otosclerosis is the single most common cause of hearing
impairment. Although the genetics of this disease are controversial, the
majority of studies indicate autosomal dominant inheritance with reduced
penetrance. We studied a large multi- generational family in which
otosclerosis has been inherited in an autosomal dominant pattern. Five of16
affected persons have surgically confirmed otosclerosis; the remaining nine
have a conductive hearing loss but have not undergone corrective surgery.
To locate the disease- causing gene we completed genetic linkage analysis
using short tandem repeat polymorphisms (STRPs) distributed over the entire
genome. Multipoint linkage analysis showed that only one genomic region, on
chromosome 15q, generated a lod score >2.0. Additional STRPs were typed
in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and
D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis
gene.
相似文献
25.
26.
Contraceptive potential of a mifepristone-nomegestrol acetate sequential regimen in women 总被引:1,自引:0,他引:1
Croxatto HB; Salvatierra AM; Fuentealba B; Massai R 《Human reproduction (Oxford, England)》1998,13(12):3297-3302
The effectiveness of a sequential regimen consisting of mifepristone, 10
mg/day for 15 days, followed by nomegestrol acetate (NOMA), 5 mg/day for
the next 13 days, for inhibiting ovulation and maintaining regular bleeding
cycles was assessed in 10 surgically sterilized volunteers who were
followed for one pretreatment and three treated cycles. Hormonal
determinations in blood and urine, ovarian ultrasonography, bleeding
records in all cycles and an endometrial biopsy taken on day 22-25 of the
third treatment cycle were used to monitor the effects of treatment. During
treatment, 24 monophasic (no sustained progesterone rise above 12 nmol/l)
and six biphasic cycles were recorded. Nine follicular ruptures were
detected echographically in these 30 treated cycles, five of which occurred
in monophasic cycles. All follicular ruptures occurred on days 1-7 of NOMA
treatment. Echographic and endocrine features of ovulatory cycles were both
present in only four treated cycles (13.3%). Development of a secretory
endometrium was achieved in all cases, but it was always irregular. Regular
withdrawal bleeding occurred in all subjects and no adverse reactions were
recorded. The ovarian and endometrial effects of this regimen justify
testing its contraceptive effectiveness in phase 2 clinical trials.
相似文献
27.
A Srour AM El Tantawi N Khouja A Zouaoui J-P Lassau J Philippon Ph Cornu 《Surgical and radiologic anatomy : SRA》1994,16(1):117-119
Summary The anterior interhemispheric approach for aneurysms of the anterior communicating artery was studied in ten cadavers. This approach presents several advantages over the pterional approach widely used in neurosurgery. It allows direct access to the region of the anterior communicating artery complex with minimal retraction of the brain and preservatioin of the olfactory tract and the gyrus rectus.
Bases anatomiques de l'abord inter-hémisphérique antérieur lors de la chirurgie des anévrysmes de l'artère communicante antérieure
Résumé Ce travail concerne l'abord neurochirurgical des anévrysmes de l'artére communicante antérieure par voie frontale interhémisphérique. L'étude anatomique a été réalisée sur dix sujets. Cette exposition possède de nombreux avantages comparée à la voie ptérionale habituelle : voie d'abord reduite médiane permettant une visualisation directe et symétrique du complexe artériel de l'artére communicante antérieure ; avec le moindre manipulation et retraction du cerveau en respectant les voies olfactives et le gyrus rectus.相似文献
28.
In recent reports we described novel hybridization patterns (HP) corresponding to 22 potentially new HLA-B locus alleles in a panel of 547 subjects studied by PCR-SSOP. Three of them correspond to new subtypes of B35. To confirm the hybridization results we have isolated DNA from PBL and performed PCR, DNA cloning and nucleotide sequencing. One of the alleles, locally called B-3505v was found in three individuals: two Hispanic, one Caucasoid. It differs from B*3505 by 3 nucleotide substitutions that lead to changes in residues 94 (Ile > Thr), 95 (Ile > Leu) and 103 (Val > Leu). B-3505v differs from B*3501 in residues 97 and 103. Another allele called B-3508v, was found in 7 individuals, (6 of 122 Toba Indians, 1 of 18 Pilaga Indians). It differs from B*3509 in two silent nucleotide substitutions (codons 135 and 138) and in one substitution in residue 156 (Arg > Leu). The new allele has a hybrid sequence between B* 3508 and B*4801. A third subtype, locally called B-3504v, observed in two Hispanic individuals, is identical to B*3512. B*3512 differs from B*3504 by 3 nucleotides and one amino acid. Substitutions in residue 95 contribute to the structure of specificity pocket F, 97 to C and E, and 156 to pockets D and E. Therefore it is possible that some of the new alleles may have different peptide binding profiles. Since differences in residue 156 have been shown to affect allorecognition and mediate GvHD, identification of such variants may have important implications in transplantation and perhaps in studies of immune responses to peptides and pathogens. 相似文献
29.
The effects of co-culture with human fibroblasts on human embryo development in vitro and implantation 总被引:5,自引:0,他引:5
Wetzels AM; Bastiaans BA; Hendriks JC; Goverde HJ; Punt-van der Zalm AP; Verbeet JG; Braat DD 《Human reproduction (Oxford, England)》1998,13(5):1325-1330
In a human in-vitro fertilization (IVF) programme, the effect of co-
culture of embryos with human fibroblasts was evaluated with respect to
pregnancy rate and embryo development. Patients were included in the study
after giving informed written consent. The IVF treatments were randomly
assigned by stratification of both age (<36 versus > or =36 years)
and previous IVF attempts (yes versus no). After fertilization was
established, the zygotes were transferred to a 4-well dish with or without
fibroblasts and cultured for 2 days. On the third day after ovum pick-up
(OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were
scored and a maximum of three embryos was transferred. Supernumerary
embryos of good quality were cryopreserved. The design of this study was a
group sequential trial with the objective of detecting differences between
pregnancy rates following IVF with conventional incubation or incubation in
co-culture with fibroblasts. This design included one evaluation at
half-way data collection. In the study, 148 patients had an OPU, of whom 77
were allocated to the co-culture group. There was no statistically
significant difference in pregnancy rate, cell number and embryo quality
between the two groups. The ongoing pregnancy rate per embryo transfer was
27% in co-culture and 30% in the conventional culture group. The
implantation rates per transferred embryo were 17 and 18% respectively.
Using a multivariate logistic regression model for the probability of
ongoing pregnancies, the odds ratio of co-culture, adjusted for age and
previous IVF attempts, was not statistically significant. In conclusion,
co-culture with human fibroblasts does not contribute to an improvement of
embryo quality nor to a higher pregnancy rate after IVF in an unselected
group of patients.
相似文献
30.