全文获取类型
收费全文 | 5209篇 |
免费 | 481篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 21篇 |
儿科学 | 227篇 |
妇产科学 | 156篇 |
基础医学 | 787篇 |
口腔科学 | 102篇 |
临床医学 | 771篇 |
内科学 | 842篇 |
皮肤病学 | 59篇 |
神经病学 | 464篇 |
特种医学 | 192篇 |
外科学 | 718篇 |
综合类 | 182篇 |
一般理论 | 6篇 |
预防医学 | 542篇 |
眼科学 | 61篇 |
药学 | 284篇 |
中国医学 | 5篇 |
肿瘤学 | 286篇 |
出版年
2023年 | 53篇 |
2022年 | 65篇 |
2021年 | 165篇 |
2020年 | 88篇 |
2019年 | 131篇 |
2018年 | 168篇 |
2017年 | 116篇 |
2016年 | 139篇 |
2015年 | 136篇 |
2014年 | 174篇 |
2013年 | 225篇 |
2012年 | 299篇 |
2011年 | 391篇 |
2010年 | 173篇 |
2009年 | 173篇 |
2008年 | 237篇 |
2007年 | 240篇 |
2006年 | 233篇 |
2005年 | 254篇 |
2004年 | 208篇 |
2003年 | 182篇 |
2002年 | 173篇 |
2001年 | 104篇 |
2000年 | 109篇 |
1999年 | 118篇 |
1998年 | 70篇 |
1997年 | 61篇 |
1996年 | 75篇 |
1995年 | 57篇 |
1994年 | 47篇 |
1993年 | 44篇 |
1992年 | 56篇 |
1991年 | 72篇 |
1990年 | 61篇 |
1989年 | 65篇 |
1988年 | 67篇 |
1987年 | 36篇 |
1986年 | 61篇 |
1985年 | 50篇 |
1984年 | 54篇 |
1983年 | 48篇 |
1982年 | 45篇 |
1981年 | 28篇 |
1980年 | 34篇 |
1979年 | 33篇 |
1978年 | 25篇 |
1974年 | 28篇 |
1973年 | 34篇 |
1972年 | 20篇 |
1967年 | 23篇 |
排序方式: 共有5705条查询结果,搜索用时 15 毫秒
41.
Gordon A Francis Gang Li Robin Casey Jian Wang Henian Cao Todd Leff Robert A Hegele 《BMC medical genetics》2006,7(1):3-7
Background
Familial partial lipodystrophy (Dunnigan) type 3 (FPLD3, Mendelian Inheritance in Man [MIM] 604367) results from heterozygous mutations in PPARG encoding peroxisomal proliferator-activated receptor-γ. Both dominant-negative and haploinsufficiency mechanisms have been suggested for this condition. 相似文献42.
43.
Genetic basis for conversion of rough-to-smooth colony morphology in Actinobacillus actinomycetemcomitans
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)
The basis of the rough-to-smooth conversion of Actinobacillus actinomycetemcomitans was examined. Smooth variants often contained mutations at the flp promoter region. Replacing the mutated flp promoter with the wild-type promoter restored the rough phenotype. The expression level of the flp promoter was approximately 100-fold lower in smooth than in rough strains. Mutations of the flp promoter are a cause of the rough-to-smooth conversion. 相似文献
44.
45.
Differential gene expression in ovarian carcinoma: identification of potential biomarkers 总被引:13,自引:0,他引:13
下载免费PDF全文
![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Hibbs K Skubitz KM Pambuccian SE Casey RC Burleson KM Oegema TR Thiele JJ Grindle SM Bliss RL Skubitz AP 《The American journal of pathology》2004,165(2):397-414
Ovarian cancer remains the fifth leading cause of cancer death for women in the United States. In this study, the gene expression of 20 ovarian carcinomas, 17 ovarian carcinomas metastatic to the omentum, and 50 normal ovaries was determined by Gene Logic Inc. using Affymetrix GeneChip HU_95 arrays containing approximately 12,000 known genes. Differences in gene expression were quantified as fold changes in gene expression in ovarian carcinomas compared to normal ovaries and ovarian carcinoma metastases. Genes up-regulated in ovarian carcinoma tissue samples compared to more than 300 other normal and diseased tissue samples were identified. Seven genes were selected for further screening by immunohistochemistry to determine the presence and localization of the proteins. These seven genes were: the beta8 integrin subunit, bone morphogenetic protein-7, claudin-4, collagen type IX alpha2, cellular retinoic acid binding protein-1, forkhead box J1, and S100 calcium-binding protein A1. Statistical analyses showed that the beta8 integrin subunit, claudin-4, and S100A1 provided the best distinction between ovarian carcinoma and normal ovary tissues, and may serve as the best candidate tumor markers among the seven genes studied. These results suggest that further exploration into other up-regulated genes may identify novel diagnostic, therapeutic, and/or prognostic biomarkers in ovarian carcinoma. 相似文献
46.
The histopathology of papillary thyroid hyperplasia and papillary thyroid carcinoma is similar enough to cause a diagnostic
dilemma in a few cases. Both lesions may have papillary fronds with fibrovascular cores, nuclear crowding, and nuclear anisocytosis.
Formalin-fixed paraffin-embedded tissues from 30 randomly selected patients with papillary thyroid hyperplasia and an equal
number from patients with papillary thyroid carcinoma were analyzed for expression of cytokeratin 19 (CK19), galectin-3, and
HBME-1. Cases of papillary thyroid carcinoma had moderate to strong CK19, galectin-3, and HBME-1 reactivity although both
CK19 and galectin-3 showed positive staining in a significant number of nonneoplastic thyroid cases. HBME-1 was uncommon in
the nonneoplastic cases. These results indicate that HBME-1 may be useful in helping to distinguish papillary thyroid carcinoma
from hyperplasia in diagnostically difficult cases. 相似文献
47.
The serine/threonine kinase Pim-2 is a transcriptionally regulated apoptotic inhibitor 总被引:13,自引:0,他引:13
Fox CJ Hammerman PS Cinalli RM Master SR Chodosh LA Thompson CB 《Genes & development》2003,17(15):1841-1854
48.
Casey Graham; Plummer Sarah; Hoeltge Gerald; Scanlon David; Fasching Clare; Stanbridge Eric J. 《Human molecular genetics》1993,2(11):1921-1927
Rearrangements or deletions of chromosome 17 are the most frequentlyobserved genetic changes identified in breast tumors. Molecularanalyses suggest that in addition to the p53 gene on 17p13.1there may be at least three other tumor suppressor genes onchromosome 17 involved in breast cancer. Regions of loss ofheterozygosity (LOH) identified on 17p13.3 and 17q12-qter occurfrequently in breast tumors, and the BRCA-1 gene has been mappedto 17q21 by genetic linkage analysis. Here we provide biologicalevidence for the presence of a growth suppressor gene(s) onchromosome 17 that results In the In vitro growth suppressionof the p53 wild-type MCF 7 breast cancer cell line. We haveIntroduced a normal chromosome 17 into MCF 7 cells by microcellmediatedchromosome transfer (MMCT), and demonstrate that cells growtharrest before 10 to 12 population doublings. In contrast, theintroduction of a normal chromosome 13 had no effect upon growthof these cells either In vitro or In vivo. These data providedirect functional evidence for the presence of a growth suppressorgene(s) on chromosome 17, which is not p53, and which may representone of several gene(s) that play a critical role in the developmentof breast cancer. 相似文献
49.
Cerebral Processing of Acute Skin and Muscle Pain in Humans 总被引:12,自引:0,他引:12
50.
A longitudinal study of maternal serum inhibin-A, inhibin-B, activin-A, activin-AB, pro-alphaC and follistatin during pregnancy 总被引:6,自引:1,他引:6
Fowler PA; Evans LW; Groome NP; Templeton A; Knight PG 《Human reproduction (Oxford, England)》1998,13(12):3530-3536
Maternal serum concentrations of inhibin-A, inhibin-B, activin-A,
activin-AB, pro-alphaC-related inhibin forms, total follistatin, steroids
and gonadotrophins were measured longitudinally in six normal singleton
pregnancies. Maternal venous blood was collected randomly during a
spontaneous follicular phase prior to donor insemination, at 5, 7, 9, 11,
16, 20, 24, 28, 32 and 36 weeks after the first missed menses and in the
early puerperium. Steroid and gonadotrophin profiles conformed to previous
reports. While at week 5 of gestation inhibin-A, activin-A and follistatin
concentrations were similar to those at the follicular phase, all three
increased progressively (P < 0.001) to maximal concentrations in week
36: approximately 48-fold (3740 +/- 1349 ng inhibin-A/ml), approximately
22-fold (6109 +/- 1443 ng activin-A/ml) and approximately 10-fold (3563 +/-
418 ng follistatin/ml) higher. Pro- alphaC concentrations reached a maximum
in weeks 5 (approximately 5- fold, P < 0.001) and 36 (1027 +/- 174
pg/ml, P < 0.01). Inhibin-B (71 +/- 23 pg/ml prior to pregnancy) was
undetectable (<12 pg/ml) between week 5-16 of gestation but increased
slightly in the third trimester (26 +/- 7 pg/ml in week 36). Activin-AB was
undetectable throughout pregnancy. Post-partum concentrations of inhibin-A
(41 +/- 12 ng/ml), inhibin-B (<12 pg/ml), activin-A (950 +/- 149 pg/ml),
pro-alphaC (128 +/- 22 pg/ml) and follistatin (990 +/- 79 ng/ml) were
substantially lower than at week 36 of gestation. The activin-A:follistatin
ratio increased from 0.5 in week 5 to 1.8 in week 36, suggesting that more
free activin-A is available in the maternal circulation during late
pregnancy.
相似文献