全文获取类型
收费全文 | 19832篇 |
免费 | 1747篇 |
国内免费 | 1028篇 |
专业分类
耳鼻咽喉 | 77篇 |
儿科学 | 456篇 |
妇产科学 | 464篇 |
基础医学 | 4528篇 |
口腔科学 | 417篇 |
临床医学 | 1710篇 |
内科学 | 3481篇 |
皮肤病学 | 232篇 |
神经病学 | 1428篇 |
特种医学 | 296篇 |
外国民族医学 | 6篇 |
外科学 | 983篇 |
综合类 | 3279篇 |
现状与发展 | 5篇 |
预防医学 | 1297篇 |
眼科学 | 261篇 |
药学 | 1738篇 |
2篇 | |
中国医学 | 200篇 |
肿瘤学 | 1747篇 |
出版年
2024年 | 13篇 |
2023年 | 161篇 |
2022年 | 342篇 |
2021年 | 511篇 |
2020年 | 526篇 |
2019年 | 516篇 |
2018年 | 607篇 |
2017年 | 658篇 |
2016年 | 757篇 |
2015年 | 909篇 |
2014年 | 1232篇 |
2013年 | 1457篇 |
2012年 | 1363篇 |
2011年 | 1501篇 |
2010年 | 1285篇 |
2009年 | 1224篇 |
2008年 | 1322篇 |
2007年 | 1317篇 |
2006年 | 1267篇 |
2005年 | 980篇 |
2004年 | 912篇 |
2003年 | 708篇 |
2002年 | 584篇 |
2001年 | 503篇 |
2000年 | 377篇 |
1999年 | 296篇 |
1998年 | 220篇 |
1997年 | 205篇 |
1996年 | 147篇 |
1995年 | 134篇 |
1994年 | 109篇 |
1993年 | 69篇 |
1992年 | 62篇 |
1991年 | 72篇 |
1990年 | 50篇 |
1989年 | 50篇 |
1988年 | 31篇 |
1987年 | 18篇 |
1986年 | 26篇 |
1985年 | 24篇 |
1984年 | 11篇 |
1983年 | 4篇 |
1982年 | 9篇 |
1981年 | 5篇 |
1980年 | 6篇 |
1979年 | 10篇 |
1978年 | 5篇 |
1976年 | 5篇 |
1971年 | 2篇 |
1906年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
G. V. Petrova V. A. Adarichev A. A. Krivenko G. S. Dymshits A. L. Markel' G. S. Yakobson 《Bulletin of experimental biology and medicine》1997,124(2):773-775
Sensitivity of normotensive Wistar rats and NISAG rats (with hereditary arterial hypertension) to heat stress is compared
at the organism and cell levels. High temperature sensitivity of NISAG rats correlates with a low content of the main heat
shock protein HSP70. This relationship can serve as a biochemical marker of predisposition to arterial hypertension.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 171–173, August, 1997 相似文献
2.
D J Bowen 《Journal of clinical pathology》2002,55(1):1-18
This review focuses on selected areas that should interest both the scientist and the clinician alike: polymorphisms within the factor VIII and factor IX genes, their linkage, and their ethnic variation; a general assessment of mutations within both genes and a detailed inspection of the molecular pathology of certain mutations to illustrate the diverse cause–effect relations that exist; a summary of current knowledge on molecular aspects of inhibitor production; and an introduction to the new areas of factor VIII and factor IX catabolism. An appendix defining various terms encountered in the molecular genetics of the haemophilias is included, together with an appendix providing accession numbers and locus identification links for accessing gene and sequence information in the international nucleic acid databases. 相似文献
3.
BACKGROUND: The responses of mice to the mite allergen Der p 1 have been used to study the mechanisms of allergic sensitization and the development of new types of immunotherapy. Many of the studies require a knowledge of the T cell epitopes, and because Der p 1 is polymorphic, the effect of natural amino acid substitution in the allergen. The intranasal administration of peptides containing T cell epitopes can induce a mucosal tolerance but it is not known if the major activity is limited to stimulatory peptides and if, as found for autoimmunity, some epitopes are not inhibitory. OBJECTIVE: To determine and compare the sequences of Der p 1 which contain stimulatory epitopes for the high responding H-2(b) and H-2(q) mice and the sequences which induce tolerance by intranasal administration of peptides. METHODS: T cell responses of mice immunized with Der p 1 were measured by in vitro T cell stimulation assays so an extensive study of epitope recognition and intranasal tolerance could be made. Synthetic peptides were used to examine the stimulatory and inhibitory ability of all Der p 1 sequences and to map the major H-2(b) epitope in detail. This included the effect of the common polymorphic amino acid 124 substitution found within this epitope. RESULTS: Three and two regions, respectively, were found to contain stimulatory T cell epitopes for H-2(b) and H-2(q) mice. The peptides in these regions were also the most active at inducing intranasal tolerance for the responding haplotype. The correspondence between inhibitory and stimulatory peptides was maintained for the fine mapping of the major H-2(b) epitope. This was found about a core region of 118-126 which was overlapping but separate to a consensus sequence for the binding of endogeneous peptides. Peptides with alanine at the naturally polymorphic residue 124 stimulated and inhibited responses to Der p 1 more effectively, while peptides with the valine 124 variant were immunogenic but poorly cross-reactive. CONCLUSIONS: The intranasal administration of peptides representing each of five epitopes recognized by two strains of mice were able to induce mucosal tolerance and the major tolerizing activity was limited to these epitopes. The position of the core major epitope for C57 mice, which differs from a previously predicted epitope, and its specificity for the natural alanine 124 variant is described. 相似文献
4.
Marie-Paule Roth Hlne Coppin Patrick Descoins Jean-Bernard Ruidavets Anne Cambon-Thomsen Michel Clanet 《Journal of neuroimmunology》1991,34(2-3):215-222
The polymorphism at the HLA-DPB1 locus has been characterized in a large number of patients with multiple sclerosis (n = 112) and in healthy controls (n = 115). Both patients and controls lived in the southwest of France (in the Pyrénées Atlantiques) and had similar ethnic background. The typing procedure involved the selective amplification of the second exon of the DPB1 locus by polymerase chain reaction, followed by hybridization of the amplified DNA with 14 sequence-specific oligonucleotide probes. Individual alleles were identified by the pattern of hybridization of the different probes. The distribution of the DPB1 alleles was not significantly different in multiple sclerosis patients and controls (p = 0.11). This does not corroborate the reported association of multiple sclerosis with the primed lymphocyte typing (PLT)-defined DPw4 specificity and is not in favour of a role played by polymorphic residues of the DP molecule in susceptibility to multiple sclerosis. 相似文献
5.
6.
Hui-Ju Wen Ying-Chu Lin Yung-Ling Lee Yueliang Leon Guo 《Pediatric allergy and immunology》2006,17(7):489-494
High cord blood immunoglobulin E (cbIgE) is known to be associated with increased risks of atopic diseases in childhood. The relationship between genetic polymorphisms and high cbIgE has not been well documented. A cross-sectional study was conducted to assess the association between cbIgE and genetic polymorphisms of interleukin (IL)-4 -590C/T, the beta-subunit of the high-affinity receptor for IgE (FcepsilonRI-beta) E237G, lymphotoxin (LT)-alphaNcoI alleles, and tumor necrosis factor (TNF)-alpha -308G/A. A total of 320 mother-neonate pairs were recruited from four maternity hospitals from different locations of Taiwan. Cord blood was obtained and assayed for cbIgE. Polymerase chain reaction followed by restriction fragment length polymorphism was used to assess the genotypes. Three hundred pairs of mothers and neonates were included in the final analysis. Infants with IL-4 -590 C allele were found to have higher risk of elevated cbIgE (> or =0.35 IU/ml, 24.3%) (p = 0.004). After adjusting for gender, birth order, maternal age, and history of allergic disease in maternal and paternal families, odds ratios for CC and CT genotypes were 4.41 and 3.16 (95% confidence interval 0.78-22.67, and 1.66-6.13), respectively, using TT genotype as reference. The genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha were not associated with cbIgE before or after the adjustment. Our finding suggested a significant association of cbIgE with genetic polymorphism of IL-4 -590C/T, but not with the genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha. 相似文献
7.
8.
PROBLEM: There is substantial data that support the efficacy of paternal leukocyte immunization (PLI) for the treatment of alloimmune mediated miscarriage; however, there is confusion regarding the laboratory test that should be performed to determine levels of maternal anti-paternal leukocyte antibodies (MAPLA). METHOD: Popular methodologies employed include: 1) microcytotoxicity (MCX), 2) mixed lymphocyte culture (MLC), and 3) cell flow cytometry crossmatch (FCXM). Cell flow cytometry crossmatch correlates well with the more difficult MLC assay although the former proves the more sensitive study. This work compares the MCX assays with FCXM. The study group consisted of ten women who had a history of three or more spontaneous abortions (SABs). All ten had very low levels (<10%) of MAPLA as measured by FCXM. Following PLI all subjects demonstrated elevated levels (>50%) of MAPLA by FCXM. At 12 weeks gestation, sera were simultaneously measured for MAPLA by MCX and FCXM. RESULTS: Although all ten patients had very high levels of MAPLA by FCXM during pregnancy, five of ten had antibodies to HLA Class I and two of ten had antibodies to HLA Class II paternal antigens by MCX. Furthermore, all patients who were positive by MCX to paternal Class I antigens were also positive to Class I antigens not seen in either parent. Both patients who were positive by MCX to paternal Class II antigens were also positive to maternal Class II antigens. Notable is that all ten women eventually delivered healthy infants. CONCLUSION: Based on this preliminary study, the MCX assay is neither sensitive or reliable enough to determine the need and/or to monitor the effectiveness of PLI. Flow cytometry should be the modality of choice when determining the need for alloimmunotherapy and to monitor the effectiveness of treatment. 相似文献
9.
Donna M. Ballantine Shelley A. Klemm Terry J. Tunny Michael Stowasser Richard D. Gordon 《Clinical and experimental pharmacology & physiology》1994,21(3):215-218
1. Aldosterone levels in patients with unilateral aldosterone-producing adenomas may be responsive or unresponsive to the renin-angiotensin system, with the former often previously misdiagnosed as bilateral adrenal hyperplasia. 2. In tumours from patients in the responsive subgroup, renin mRNA is expressed in greater amounts than in tumours from patients in the unresponsive subgroup, or in normal adrenals. 3. We compared the frequency of four renin gene polymorphisms in peripheral blood DNA from the two subgroups and found significant associations between BglI, TaqI and HinfI restriction fragment length polymorphisms (RFLP) and aldosterone responsiveness. 4. Allelic variation in the constitutive renin gene was associated with a specific cause of hypertension. 相似文献
10.
目的:研究中国汉族群体中α艾杜糖苷酶基因D4S111位点的遗传多态性。方法:采用扩增片段长度多态性(AmpFLP)分析技术,检测了广州地区汉族无血缘关系健康个体97名。结果:D4S111位点,在97名无关个体中发现5个等位基因和9种基因型,等位基因片段长度为830~510bp,基因频率为00052~03608,PIC为05966,杂合性为078。结论:中国汉族群体中D4S111位点具有高度多态性,并与其它种族间存在差异性。 相似文献