全文获取类型
收费全文 | 6508篇 |
免费 | 656篇 |
国内免费 | 310篇 |
专业分类
耳鼻咽喉 | 34篇 |
儿科学 | 148篇 |
妇产科学 | 86篇 |
基础医学 | 1642篇 |
口腔科学 | 256篇 |
临床医学 | 543篇 |
内科学 | 1047篇 |
皮肤病学 | 173篇 |
神经病学 | 356篇 |
特种医学 | 94篇 |
外国民族医学 | 3篇 |
外科学 | 413篇 |
综合类 | 954篇 |
现状与发展 | 1篇 |
预防医学 | 234篇 |
眼科学 | 121篇 |
药学 | 649篇 |
中国医学 | 389篇 |
肿瘤学 | 331篇 |
出版年
2024年 | 13篇 |
2023年 | 79篇 |
2022年 | 150篇 |
2021年 | 218篇 |
2020年 | 265篇 |
2019年 | 177篇 |
2018年 | 189篇 |
2017年 | 229篇 |
2016年 | 258篇 |
2015年 | 260篇 |
2014年 | 350篇 |
2013年 | 547篇 |
2012年 | 327篇 |
2011年 | 414篇 |
2010年 | 349篇 |
2009年 | 367篇 |
2008年 | 368篇 |
2007年 | 372篇 |
2006年 | 347篇 |
2005年 | 349篇 |
2004年 | 327篇 |
2003年 | 266篇 |
2002年 | 209篇 |
2001年 | 208篇 |
2000年 | 174篇 |
1999年 | 138篇 |
1998年 | 115篇 |
1997年 | 95篇 |
1996年 | 90篇 |
1995年 | 76篇 |
1994年 | 64篇 |
1993年 | 41篇 |
1992年 | 22篇 |
1991年 | 11篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1985年 | 1篇 |
排序方式: 共有7474条查询结果,搜索用时 15 毫秒
11.
Slotwiński R Olszewski WL Chaber A Slodkowski M Zaleska M Krasnodebski IW 《Journal of clinical immunology》2002,22(5):289-296
The clinical implications of increased cytokine levels after major surgery remain unclear. In this study, systemic concentration of a spectrum of cytokines, including interleukins IL-6, IL-8, IL-10, IL-1ra, and soluble tumor necrosis factor receptor-I (sTNF-RI) was examined in patients with and without postoperative septic complications following colorectal surgery. Although there were no significant changes in IL-1, TNF-, and IL-8 serum levels during the observation period, there was a significant rise in IL-6, IL-1ra, and sTNF-RI concentrations in the entire group of patients between postoperative day 1 and 14. There were no differences between the group without and with local complications when IL-6, IL-1ra, and IL-10 were examined. The serum levels of sTNF-RI, IL-1ra, and IL-6 were found to be sensitive indicators of the pro- and anti-inflammatory response to the surgical trauma, but only sTNF-RI turned out to be a sensitive early marker of local septic postoperative complications in patients with colorectal carcinoma. 相似文献
12.
Kinetics of the phenotype and function of murine peritoneal macrophages following acute inflammation 总被引:2,自引:0,他引:2
Wu Q Feng Y Yang Y Jingliu Zhou W He P Zhou R Li X Zou J 《Cellular & molecular immunology》2004,1(1):57-62
This study was undertaken to have a better understand for the process and the underlying mechanisms to limitmacrophage activation and population of activated macrophages.A comprehensive kinetics of cytokineproduction was performed in murine peritoneal macrophages recovered from Balb/c mice at various timeduring the course of an intraperitoneal injection with thioglycollate (TG).The expression of cell surfacemolecules such as MHC-Ⅰ,MHC-Ⅱ,B7-1 and B7-2 of these macrophages were also determined by flowcytometry.The present findings of our research suggested that the population of activated macrophages and theactivation of macrophages (including cytokines production and expression of cell surface functional molecules)were strictly controlled during inflammation process.This is one of the important mechanisms to retain the hosthomeostasis.Cellular & Molecular Immunology.2004;1(1):57-62. 相似文献
13.
de Groot J Kruijt L Scholten JW Boersma WJ Buist WG Engel B van Reenen CG 《Immunology》2005,115(4):495-505
The capacity of farm animals to produce cytokines could be an important determinant of robustness and health. From research in rodents and humans it appears that the production and the balance of T helper 1 (Th1) and T helper 2 (Th2)-type cytokines influences susceptibility to autoimmune and infectious diseases. It is known that pigs show a large variation in many immune response parameters. So far the extent of individual variation in the production of Th1- and Th2-type cytokines in commercial outbred pigs has not been reported. In the current experiment we determined mRNA expression, as well as protein production of cytokines in 32 pigs from eight litters. From each litter two male and two female pigs were tested at 2, 5 and 8 weeks of age. Two Th1-type cytokines, interleukin (IL)-2 and interferon (IFN)-gamma, and two Th2-type cytokines, IL-4 and IL-10, were measured after phytohaemagglutinin (PHA)-stimulation of blood mononuclear cells. Cytokine production and the Th1/Th2-ratio were highly variable. The variation in cytokine protein production was moderately consistent across ages, i.e. pigs that produced high levels of cytokine at 2 weeks of age tended to do so as well at 5 and 8 weeks of age. Cytokine production tended to increase with age, and gilts and boars differed in their IL-2/IL-4 ratio. Unexpectedly, age, gender and litter effects often differed for mRNA and protein production data. We hypothesize that cytokine production is a consistent trait in pigs, especially at the protein production level. Future investigations in more animals and across a wider age range are necessary. 相似文献
14.
Comparison of different metrics, using three large samples of haplotypes from different populations, demonstrates that rho is the most efficient measure of association between pairs of single nucleotide polymorphisms (SNPs). Pairwise data can be modeled, using composite likelihood, to describe the decline in linkage disequilibrium with distance (the Malecot model). The evidence from more isolated populations (Finland, Sardinia) suggests that linkage disequilibrium extends to 427-893 kb but, even in samples representative of large heterogeneous populations, such as CEPH, the extent is 385 kb or greater. This suggests that isolated populations are not essential for linkage disequilibrium mapping of common diseases with SNPs. The in parameter of the Malecot model (recombination and time), evaluated at each SNP, indicates regions of the genome with extensive and less extensive disequilibrium (low and high values of in respectively). When plotted against the physical map, the regions with extensive and less extensive linkage disequilibrium may correspond to recombination cold and hot spots. This is discussed in relation to the Xq25 cytogenetic band and the HFE gene region. 相似文献
15.
K. Kobayashi T. Suda K. Nan-ya N. Sakaguchi S. Sakaguchi I. Miki 《Inflammation research》2006,55(8):335-341
Objective SKG mice have a point mutation of the zeta-associated protein of 70 kD (ZAP-70) and spontaneously develop a severe polyarthritis
in the conventional condition, whereas they are healthy under the specific pathogen free (SPF) condition. The purpose of this
study was to investigate the cytokine production from splenocytes in SKG mice developing arthritis under the SPF condition.
Material SKG and BALB/c mice were intraperitoneally injected with zymosan A under the SPF condition. Spleen was isolated 1, 2 or 8 weeks
after the intraperitoneal injection of saline or zymosan A. Splenocytes were cultured with concanavalin A. Cytokine production
and proliferation were measured 48 and 72 h after the culture.
Results An intraperitoneal injection of zymosan A induced severe polyarthritis with increased levels of rheumatoid factor and interleukin
6 (IL-6) only in SKG mice. Splenocytes from SKG mice did not proliferate well maybe because of less productivity of IL-2.
The IL-4 production from splenocytes of SKG mice was higher, while interferon-γ production was lower than those of BALB/c
mice. An injection of zymosan A reduced the IL-4 production only in SKG mice.
Conclusions SKG mice do not develop arthritis under the SPF condition possibly because of a low proliferative activity of T cells and
Th2-predominance.
Received 27 December 2005; returned for revision 7 February 2006; accepted by A. Falus 10 March 2006 相似文献
16.
脐血来源的树突状细胞增强CIK细胞的杀伤作用 总被引:7,自引:2,他引:7
为确认体外诱导出的成熟脐血来源树突状细胞 (CBDC )可以引发强大抗肿瘤免疫反应 ,CBDC培养 12d后用电镜分析形态 ,用流式细胞仪检测其表型。在不同培养时间 ,用3 H TdR掺入法检测CBDC和细胞因子诱导杀伤细胞 (CIK )的扩增功能 ;用MTT法检测被CBDC激活的CIK抗肿瘤活性。结果表明 ,体外诱导出形态典型的DC ,高表达主要组织相容性抗原I、II类分子、CD5 4 ,也表达CD80、CD83、CD1a,不表达CD6 8。体外培养 12d成熟的CBDC ,能使CIK以最高的比率扩增 ,2种细胞最佳混合比为 1∶10时被激活的CIK杀伤BEL 74 0 2肝癌细胞的功能最强 ,最佳效靶比为 80∶1 相似文献
17.
18.
Grasso G Massai L Migliaccio P Picciolini E Muscettola M 《American journal of reproductive immunology (New York, N.Y. : 1989)》2001,45(4):217-225
PROBLEM: Plasma interferon (IFN)-beta levels, lymphocyte responsiveness, and evaluation of the relationship between circulating antiviral activity (AA) and IFN-gamma production were studied in pregnant women and nonpregnant age-matched controls with the objective of elucidating the downregulation of IFN-gamma production in successful pregnancy. METHOD OF STUDY: In plasma and supernatants of peripheral blood mononuclear cell (PBMC) cultures, stimulated with staphylococcal enterotoxin A (SEA) superantigen, from 43 pregnant women with a history of normal pregnancy and 30 healthy nonpregnant age-matched controls, levels of AA were measured in a micromethod by inhibition of the cytopathic effect (CPE) caused by vesicular stomatitis virus (VSV) in the human amnionic cell line (WISH). RESULTS: Significantly higher plasma AA (60% was IFN-gamma and residual activity was acid-labile IFN-like) was present in pregnant women than controls. On the other hand, SEA-activated PBMCs from pregnant women produced significantly lower IFN-gamma levels than those of nonpregnant women. Furthermore, maternal plasma AA levels correlated negatively with IFN-gamma production by SEA-stimulated PBMCs. CONCLUSION: The hypothesis that successful pregnancy requires downregulation of IFN-gamma is only partially sustained, suggesting that the immunology of pregnancy is more complex and that murine and human pregnancy have different cytokine profiles. 相似文献
19.
High endothelial-like venules in chronically inflamed periodontal tissues exchange polymorphs 总被引:1,自引:0,他引:1
A survey of 58 gingival biopsies revealed the presence of periodontal high endothelial-like venules (PHELVs) in chronically inflamed gingival tissues. PHELVs were found to exchange polymorphonuclear cells (PMNs) almost exclusively in advanced periodontitis, with PMNs greatly exceeding the number of mononuclear cells found in PHELVs (P less than 0.001). Electron microscopy confirmed the emigration of PMNs from these vessels. The enzyme histochemical and ultrastructural features as well as the 35SO4 uptake properties of PHELVs were similar to those of the well-characterized high endothelial venules (HEVs) of rat lymph nodes. It is generally accepted that HEVs in lymphoid tissues and inflammatory sites are specially adapted to assist in the emigration of lymphocytes. However, the observation of preferential PMN emigration in the apparent absence of lymphocyte exchange from PHELVs compels further investigation of other possible functions for HEVs. In relation to this, endothelial cells are capable of producing potent cytokines and inflammatory mediators which may contribute to the development of lesions, and the possibility is discussed that high endothelial cells are functionally adapted to enhance the production of such factors. 相似文献
20.
Adjuvant-dependent modulation of Th1 and Th2 responses to immunization with beta-amyloid 总被引:6,自引:0,他引:6
Cribbs DH Ghochikyan A Vasilevko V Tran M Petrushina I Sadzikava N Babikyan D Kesslak P Kieber-Emmons T Cotman CW Agadjanyan MG 《International immunology》2003,15(4):505-514
The role of adjuvant on the T(h)1 and T(h)2 immune responses to Abeta-immunotherapy (Abeta(42 )peptide) was examined in wild-type mice. Fine epitope analysis with overlapping oligomers of the Abeta(42) sequence identified the 1-15 region as a dominant B cell epitope. The 6-20 peptide was recognized only weakly by antisera from mice administrated with Abeta(42) peptide formulated in complete Freund's adjuvant (CFA), alum or TiterMax Gold (TMG). However, mice immunized with Abeta(42) mixed with QS21 induced a significant antibody response to the 6-20 peptide. The only T cell epitope found was within the 6-28 sequence of Abeta(42). QS21 and CFA induced the strongest humoral response to Abeta, alum was intermediate, and TMG the weakest adjuvant. Analysis of antibody isotypes specific for Abeta indicates that alum induces primarily T(h)2-type immune response, whereas TMG, CFA and QS21 shift the immune responses toward a T(h)1 phenotype. Stimulation of splenocytes from Abeta-immunized mice with Abeta(40) peptide induced strikingly different cytokine expression profiles. QS21 and CFA induced significant IFN-gamma, IL-4 and tumor necrosis factor-alpha expression, whereas alum induced primarily IL-4 production. As T(h)1-type immune responses have been implicated in many autoimmune disorders, whereas T(h)2-type responses have been shown to inhibit autoimmune disease, the choice of adjuvant may be critical for the design of a safe and effective immunotherapy for Alzheimer's disease. 相似文献