全文获取类型
收费全文 | 4167篇 |
免费 | 96篇 |
国内免费 | 92篇 |
专业分类
耳鼻咽喉 | 40篇 |
儿科学 | 226篇 |
妇产科学 | 81篇 |
基础医学 | 955篇 |
口腔科学 | 33篇 |
临床医学 | 261篇 |
内科学 | 1052篇 |
皮肤病学 | 49篇 |
神经病学 | 740篇 |
特种医学 | 44篇 |
外科学 | 206篇 |
综合类 | 179篇 |
预防医学 | 173篇 |
眼科学 | 70篇 |
药学 | 129篇 |
1篇 | |
中国医学 | 3篇 |
肿瘤学 | 113篇 |
出版年
2023年 | 49篇 |
2022年 | 131篇 |
2021年 | 144篇 |
2020年 | 121篇 |
2019年 | 163篇 |
2018年 | 153篇 |
2017年 | 116篇 |
2016年 | 110篇 |
2015年 | 131篇 |
2014年 | 221篇 |
2013年 | 237篇 |
2012年 | 164篇 |
2011年 | 210篇 |
2010年 | 146篇 |
2009年 | 192篇 |
2008年 | 248篇 |
2007年 | 163篇 |
2006年 | 179篇 |
2005年 | 146篇 |
2004年 | 119篇 |
2003年 | 117篇 |
2002年 | 87篇 |
2001年 | 82篇 |
2000年 | 65篇 |
1999年 | 68篇 |
1998年 | 55篇 |
1997年 | 46篇 |
1996年 | 38篇 |
1995年 | 46篇 |
1994年 | 38篇 |
1993年 | 37篇 |
1992年 | 27篇 |
1991年 | 23篇 |
1990年 | 20篇 |
1989年 | 19篇 |
1988年 | 23篇 |
1987年 | 11篇 |
1986年 | 10篇 |
1985年 | 60篇 |
1984年 | 53篇 |
1983年 | 38篇 |
1982年 | 46篇 |
1981年 | 48篇 |
1980年 | 36篇 |
1979年 | 29篇 |
1978年 | 19篇 |
1977年 | 15篇 |
1976年 | 12篇 |
1975年 | 11篇 |
1974年 | 14篇 |
排序方式: 共有4355条查询结果,搜索用时 15 毫秒
31.
G Tricot J P Fryns J Thomas P Moerman A Broeckaert-Van Orshoven K Vermaelen H Van Den Berghe 《Cancer Genetics and Cytogenetics》1983,9(3):239-244
A 5q- anomaly associated with other chromosome anomalies was found in the infiltrated bone marrow of a patient with a highly malignant teratoma originally located in the mediastinum. There was no evidence of a second malignancy, and it is likely that the 5q- anomaly was, indeed, associated with the malignant teratoma cells. 相似文献
32.
Falk W. Lohoff Marion Lautenschlager Johannes Mohr Thomas N. Ferraro Thomas Sander Jürgen Gallinat 《Neuroscience letters》2008
Vesicular monoamine transporters are involved in the presynaptic packaging of norepinephrine, dopamine and serotonin into storage vesicles. The vesicles release their content upon arrival of an action potential into the synaptic cleft. Dysregulation of monoaminergic neurotransmission has been long postulated to play a relevant role in the etiology of neuropsychiatric disorders. The gene encoding the vesicular monoamine transporter 1 (VMAT1/SLC18A1) maps to chromosome 8p21, a region where several linkage peaks overlap between schizophrenia, bipolar disorder and anxiety-related personality traits. In this study, we tested the hypothesis that the missence variation Thr136Ile in the VMAT1/SLC18A1 gene is associated with anxiety-related personality traits. We tested a total of 337 unrelated subjects of German descent (167 male, 170 female). All participants were carefully screened for psychiatric disorders. The self-report State–Trait Anxiety Inventory (STAI) was completed by all subjects. Genotypes were obtained for the Thr136Ile (rs1390938) variation in the VMAT1 gene for all subjects. Genotype effects on personality variables were computed with MANOVA including age as a co-variant and gender as independent factor (MANCOVA). Results show that STAI scores were significantly affected by genotype (F = 3.108; d.f. = 4,331; p = 0.015) and age (F = 7.233; d.f. = 2,331; p = 0.001) but not by gender. A gender-by-genotype effect was observed for both the STAI state (p = 0.052) and trait score (p = 0.035). Dissection of the group by gender and subsequent contrast analysis of the genotype effects performed within the female group showed significant results (STAI state: Thr/Ile vs. Ile/Ile: T = 4.408, p = 0.0004; STAI trait: Thr/Ile vs. Ile/Ile: T = 3.074, p = 0.009) but not in the male group. Our findings support the hypothesis that anxiety-related personality traits are associated with variation in the VMAT1/SLC18A1 gene. 相似文献
33.
Kunnas TA Lehtimäki T Karhunen PJ Laaksonen R Janatuinen T Vesalainen R Nuutila P Knuuti J Nikkari ST 《Journal of molecular medicine (Berlin, Germany)》2004,82(12):821-825
Most of the effects of estrogens are mediated by estrogen receptors. Vascular endothelial cells and smooth muscle cells express estrogen receptor (ESR1) in both genders. A long genotype group of a common thymine-adenine (TA) dinucleotide repeat polymorphism in the regulatory region of this gene has previously been related to coronary artery disease. The present study examined whether coronary blood flow is affected by this genotype. A total of 49 healthy men were genotyped by PCR and divided into three groups according to median number of the ESR1 promoter TA repeat (=19), i.e., in the short allele genotype group both alleles were of fewer than 19 repeats whereas in the long allele group both alleles were 19 repeats or more. The intermediate group comprised men who had one short and one long allele. Myocardial blood flow was measured by positron emission tomography using [15O]water, performed at rest and during adenosine stimulation. Men with long alleles had lower adenosine-stimulated coronary flow than those with short alleles and those with one short and one long allelle. Our results suggest that adenosine-stimulated myocardial perfusion is lower in subjects with ESR1 long alleles than the other TA repeat genotypes. 相似文献
34.
Vincent M. Riccardi Helen M. Hittner Uta Francke Jorge J. Yunis David Ledbetter Wayne Borges 《Cancer Genetics and Cytogenetics》1980,2(2):131-137
The role of del (11)(p13) as a cause of aniridia, with and without Wilms tumor, is strengthened by demonstration of this chromosome aberration in 3 patients: monozygous twin girls, both of whom have aniridia and mental retardation and one of whom has a Wilms tumor; and an unrelated boy with aniridia and ambiguous genitalia. The break points defining the interstitial deletion for the twins are 11p13 and 11p15.1, while for the boy they are 11p1302 and 11p14.1. These patients and their karyotypes substantiate the critical importance of chromosome band 11p13 (or its hemizygous representation) in the development of aniridia and an associated Wilms tumor diathesis, as had been suggested previously (Riccardi VM, Sujansky E, Smith AC, Francke U, (1978): Pediatrics 61, 604-610). 相似文献
35.
HLA-DR7 association with African Burkitt's lymphoma 总被引:1,自引:0,他引:1
Association between HLA-DR7 and Burkitt's lymphoma previously reported has been confirmed by a second study. Analysis of additional data from a second study of 33 Ghanaian patients with African Burkitt's lymphoma and 54 Ghanaian controls matched for age and ethnic origin showed that 39.4% of cases, but only 14.8% of controls, had HLA-DR7 (p less than 0.01). The relative risk of 3.7 is similar to that observed in the earlier study (3.3). Combining the earlier and present studies, analysis of clinical data from 94 patients with Burkitt's lymphoma and 116 controls shows the relative risk of Burkitt's lymphoma among individuals with HLA-DR7 was 3.4 (p less than 0.001). There was an increased relative risk of the disease associated with HLA-DR7 in: patients under 10 years of age; and patients with advanced stages of disease (Stage III or IV). However, comparison of relative risks by sequential analysis of 2 X 2 tables showed that these differences by age and stage were not statistically significant. 相似文献
36.
Summary Using a protoplast fusion technique we have been able to locate to the mitochondrial genome of the asporogenous yeast Torulopsis glabrata mutations conferring resistance to oligomycin, antimycin and diuron. When two strains differing in the size of their mtDNAs were fused the mitochondrial markers from the parent with the larger mtDNA (71–91) were transmitted predominantly among the fusion products. Both genetical and physical evidence support the occurrence of recombination in T. glabrata mitochondrial genome. Segregation of the mitochondrial genome appears to take place before the separation of the first bud from the fusion product. 相似文献
37.
Andrew J. Carroll Robert P. Castleberry Josef T. Prchal Wayne H. Finley 《Cancer Genetics and Cytogenetics》1985,18(4):303-306
Several recent reports have described cases of acute nonlymphocytic leukemia with a unique chromosome translocation, t(6;9)(p23;q34). We have studied three additional patients who have acute nonlymphocytic leukemia and t(6;9)(p23;q34). Our findings provide additional support for the suggestion that this translocation is yet another distinct cytogenetic abnormality associated with myeloproliferative disorders. 相似文献
38.
Cristina Mecucci Kristina Vermaelen Guido Tricot Andries Louwagie Jean-Louis Michaux André Bosly José Thomas Dario Barbieri Herman Van Den Berghe 《Cancer Genetics and Cytogenetics》1983,9(4):367-381
Anomalies of both No. 3 chromosomes, of the t(3q?; 3q+) type can be observed in human malignancy as reported previously. It is our experience that this anomaly is found predominantly in myeloproliferative disorders, as a rather rare event, though occurring more frequently than similar exchanges between other homologous chromosomes. Previous claims about a relationship between this anomaly and thrombocytosis could not be confirmed, but the features found in a few patients indicate that further research should be undertaken to clarify this point. 相似文献
39.
A BrdU-Hoechst 33258 treatment of living cells, which selectively induced condensation-inhibition of G-band chromatin in human and Chinese hamster chromosomes, is presented. As a consequence mitotic chromosomes showed high resolution R-banding patterns when examined by light and electron microscopy. Besides each whole chromosome identification, this procedure also permitted the electron microscopic study of specific structures, such as satellites, secondary constrictions, telomeres, centromeres, as well as G and R bands, some of them not visible by light microscopy. We have also observed that the chromatin of G and R bands behave as blocks of chromatin condensation and that G-band chromatin develops condensation along G2. Under the BrdU-Hoechst 33258 treatment, chromatin fibers seem to invert their spontaneous pattern of condensation within the chromosomes. 相似文献
40.
Palmiero Monteleone Alfonso Tortorella Vassilis Martiadis Ismene Serino Carmela Di Filippo Mario Maj 《Neuroscience letters》2007
Genes involved in serotonin transmission are likely involved in the biological predisposition to bulimia nervosa. We investigated whether the A218C polymorphism of the tryptophan-hydroxylase-1 gene was associated to bulimia nervosa and/or to some phenotypic aspects of the disorder. One hundred eighty Caucasian women (91 patients with bulimia nervosa and 89 healthy controls) were enrolled into the study. They underwent a blood sample collection for A218C polymorphism of the tryptophan-hydroxylase-1 genotyping and a clinical evaluation assessing comorbidity for Axis I and II psychiatric disorders, harm avoidance personality dimension and bulimic symptoms. The distribution of both tryptophan-hydroxylase-1 A218C genotypes and alleles did not significantly differ between patients and controls. Bulimic women with the AA genotype exhibited a more severe binge eating behavior and higher harm avoidance scores than those with CC genotype. These findings support the idea that tryptophan-hydroxylase-1 A218C polymorphism does not play a part in the genetic susceptibility to bulimia nervosa, but it seems to be involved in predisposing bulimic patients to a more disturbed eating behavior and higher harm avoidance. 相似文献