全文获取类型
收费全文 | 2311篇 |
免费 | 152篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 71篇 |
妇产科学 | 46篇 |
基础医学 | 352篇 |
口腔科学 | 43篇 |
临床医学 | 351篇 |
内科学 | 519篇 |
皮肤病学 | 39篇 |
神经病学 | 266篇 |
特种医学 | 36篇 |
外科学 | 171篇 |
综合类 | 14篇 |
一般理论 | 1篇 |
预防医学 | 227篇 |
眼科学 | 41篇 |
药学 | 123篇 |
中国医学 | 6篇 |
肿瘤学 | 156篇 |
出版年
2023年 | 12篇 |
2022年 | 38篇 |
2021年 | 43篇 |
2020年 | 31篇 |
2019年 | 44篇 |
2018年 | 56篇 |
2017年 | 45篇 |
2016年 | 48篇 |
2015年 | 78篇 |
2014年 | 106篇 |
2013年 | 114篇 |
2012年 | 167篇 |
2011年 | 168篇 |
2010年 | 79篇 |
2009年 | 84篇 |
2008年 | 156篇 |
2007年 | 153篇 |
2006年 | 144篇 |
2005年 | 137篇 |
2004年 | 173篇 |
2003年 | 146篇 |
2002年 | 151篇 |
2001年 | 18篇 |
2000年 | 17篇 |
1999年 | 16篇 |
1998年 | 31篇 |
1997年 | 33篇 |
1996年 | 14篇 |
1995年 | 20篇 |
1994年 | 17篇 |
1993年 | 17篇 |
1992年 | 8篇 |
1991年 | 2篇 |
1990年 | 8篇 |
1989年 | 7篇 |
1988年 | 4篇 |
1987年 | 8篇 |
1986年 | 6篇 |
1985年 | 8篇 |
1984年 | 9篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1981年 | 7篇 |
1980年 | 6篇 |
1979年 | 3篇 |
1978年 | 6篇 |
1974年 | 5篇 |
1972年 | 3篇 |
1965年 | 1篇 |
1913年 | 2篇 |
排序方式: 共有2466条查询结果,搜索用时 15 毫秒
61.
Naoura I Didelot A Walker F Luton D Koskas M 《American journal of obstetrics and gynecology》2011,205(4):e6-e8
Anti-N-methyl-D-aspartate receptor encephalitis is an emerging disease that affects young women. Its diagnosis can be delayed because of the neuropsychiatric symptoms in the foreground, but early removal of the associated teratoma improves the prognosis. We report the treatment of a patient with anti-N-methyl-D-aspartate receptor encephalitis that was related to an ovarian teratoma. 相似文献
62.
Verhoeff FH Le Cessie S Kalanda BF Kazembe PN Broadhead RL Brabin BJ 《Annals of tropical paediatrics》2004,24(2):161-169
In a cohort study of mothers and their infants, information was collected from women attending the antenatal services of two hospitals in a rural area of Malawi and 561 of their babies were enrolled in a follow-up study. There were 128 with a low birthweight (LBW, <2500 g), 138 with fetal anaemia (FA, cord haemoglobin <12.5 g/dl), 42 with both and 228 with a normal birthweight and no FA. Infants were seen monthly for 1 year. Risk factors for post-neonatal infant mortality (PNIM) were calculated using Cox regression analysis adjusting for LBW and FA. PNIM was 9.3%. Respiratory infections and diarrhoeal disease were the principal attributable causes of death. PNIM increased with LBW (RR 3.08, 95% CI 1.51-6.23) but not significantly so with FA (RR 1.60, 95% CI 0.78-3.27). An additional effect on PNIM was observed with maternal HIV (RR 3.44, 95% CI 1.63-7.26) and malaria at the first antenatal visit (RR 2.26, 95% CI 1.09-4.73). Illiteracy was not associated with mortality. Placental malaria in HIV-seronegative mothers was significantly associated with increased PNIM. Improving birthweight through effective antimalarial control in pregnancy will lead to a reduction in PNIM. Reduction of HIV prevalence and prevention of mother-to-child transmission of HIV must be a main target for government health policy. 相似文献
63.
64.
OBJECTIVE: In previously well infants hospitalized with acute viral bronchiolitis, the effectiveness of repeated nebulized therapy with epinephrine (EPI) was compared with treatment with albuterol (ALB) or saline placebo (PLAC). STUDY DESIGN: In this randomized, double-blind, parallel-group, controlled trial, infants received study nebulizations every 1 to 6 hours and were assessed twice daily by the research team. The primary outcome was length of hospital stay (LOS). Secondary outcomes included the time from admission until the infant had normal hydration, oxygenation, and minimal respiratory distress. RESULTS: A total of 149 infants were randomized; 50 were allocated to receive racemic EPI, 51 were given ALB, and 48 received PLAC. Baseline characteristics and pre-enrollment symptoms, signs, and therapy were similar between groups. There were no group differences in the primary outcome measure, mean LOS (hours)(+/- SD): EPI = 59.8 (62), ALB = 61.4 (54), and PLAC = 63.3 (47); P =.95 by intent-to-treat analysis. Group differences were not statistically significant in any of the secondary outcomes. CONCLUSIONS: There were no group differences in the effectiveness of therapy for infants hospitalized with bronchiolitis. Based on these results, we do not recommend routine use of either nebulized EPI or ALB in this patient group. 相似文献
65.
Xuesong Han Tongzhang Zheng Francine M. Foss Qing Lan Theodore R. Holford Nathaniel Rothman Shuangge Ma Yawei Zhang 《American journal of hematology》2010,85(1):51-56
Metabolic pathway enzymes, such as Cytochrome P450 (CYP), glutathione S‐transferase (GST), and N‐acetyltransferases (NAT) are involved in activation and detoxification of environmental carcinogens as well as drug metabolism. We hypothesized that the genetic variations in such metabolic pathways may affect NHL prognosis and survival. Follow‐up information of 496 female NHL incident cases diagnosed during 1996–2000 in Connecticut were abstracted from the Connecticut Tumor Registry in 2008; survival analyses were conducted by comparing the Kaplan‐Meier curves, and hazard ratios (HR) were computed from the Cox Proportional Hazard models adjusting for demographic and tumor characteristics which were suggested by previous studies to be determinants of NHL survival. We identified six SNPs from four metabolism genes (CYP2E1, GSTP1, GSTT1, and NAT1) that were associated with NHL survival. Specifically, polymorphisms in GSTT1 were associated with follicular lymphoma survival; and polymorphisms in CYP2E1, GSTP1, and NAT1 were associated with survival of chronic lymphocytic leukemia/small lymphocytic lymphoma. Our study suggests that genetic polymorphisms in metabolic pathways may help improve the prediction of NHL survival and prognosis. Am. J. Hematol., 2010. © 2009 Wiley‐Liss, Inc. 相似文献
66.
67.
Francine I. Vacchi Josiane A. S. Vendemiatti Vanessa Brosselin Bianca Ferreira da Silva Maria Valnice B. Zanoni Michel DeMeo Sylvie Bony Alain Devaux Gisela A. Umbuzeiro 《Environmental and molecular mutagenesis》2016,57(7):559-571
Waters receiving textile discharges can exhibit genotoxic and mutagenic activity, which has been related to the presence of dyes and aromatic amines as synthesis precursors or byproducts. The aim of this study was to identify dyes and aromatic amines in water samples impacted by textile discharges, and to evaluate the genotoxic responses of these samples using the Salmonella/microsome assay in strains TA98 and YG1041, and the Fpg‐modified comet assay in the RTL‐W1 fish cell line. The genotoxicity of river samples downstream of the discharge was greater than the upstream samples in both of the Ames tests. The Fpg‐modified comet assay detected similar levels of DNA damage in the upstream and downstream samples. Mutagenicity was not detected with TA98, except for the Quilombo River samples, but when YG1041 was used as the tester strain mutagenicity was detected for all sites with a very different profile in upstream sites relative to the other sites. The mutagenic response strongly indicated that aromatic amines or dyes were contributing to the mutagenic activity downstream. The impact of textile discharges was also confirmed by chemical analysis, because the highest concentrations of azo dyes and aromatic amines were detected in the river downstream. This study shows the value of combining assays measuring complementary endpoints to better characterize the mutagenicity of environmental samples, with the advantage that this approach provides an indication of what classes of compounds are responsible for the effect. Environ. Mol. Mutagen. 57:559–571, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
68.
69.
Bendriss-Vermare N Burg S Kanzler H Chaperot L Duhen T de Bouteiller O D'agostini M Bridon JM Durand I Sederstrom JM Chen W Plumas J Jacob MC Liu YJ Garrone P Trinchieri G Caux C Brière F 《Journal of leukocyte biology》2005,78(4):954-966
Depending on the activation status, plasmacytoid dendritic cells (PDC) and myeloid DC have the ability to induce CD4 T cell development toward T helper cell type 1 (Th1) or Th2 pathways. Thus, we tested whether different activation signals could also have an impact on the profile of chemokines produced by human PDC. Signals that induce human PDC to promote a type 1 response (i.e., viruses) and a type 2 response [i.e., CD40 ligand (CD40L)] also induced PDC isolated from tonsils to secrete chemokines preferentially attracting Th1 cells [such as interferon-gamma (IFN-gamma)-inducible protein (IP)-10/CXC chemokine ligand 10 (CXCL10) and macrophage inflammatory protein-1beta/CC chemokine ligand 4 (CCL4)] or Th2 cells (such as thymus and activation-regulated chemokine/CCL17 and monocyte-derived chemokine/CCL22), respectively. Activated natural killer cells were preferentially recruited by supernatants of virus-activated PDC, and supernatants of CD40L-activated PDC attracted memory CD4(+) T cells, particularly the CD4(+)CD45RO(+)CD25(+) T cells described for their regulatory activities. It is striking that CD40L and virus synergized to trigger the production of IFN-gamma by PDC, which induces another Th1-attracting chemokine monokine-induced by IFN-gamma/CXCL9 and cooperates with endogenous type I IFN for IP-10/CXCL10 production. In conclusion, our studies reveal that PDC participate in the selective recruitment of effector cells of innate and adaptive immune responses and that virus converts the CD40L-induced Th2 chemokine patterns of PDC into a potent Th1 mediator profile through an autocrine loop of IFN-gamma. 相似文献
70.
Faury G Wynnychenko TM Cand F Leone M Jacob MP Verdetti J Boyle WA 《Pathologie-biologie》2005,53(7):443-447
OBJECTIVE: Sepsis is a potentially life-threatening medical condition induced by viral, bacterial or fungal infection, which is characterized by systemic inflammation, hypotension and vasodilation that can lead to cardiovascular collapse. Increased activity of elastases, enzymes which degrade the extracellular matrix components including elastin, has been demonstrated in plasma of septic patients. Since elastin peptides (EP), by binding to an elastin-laminin receptor on vascular endothelial and smooth muscle cells, induce dose-dependent vasodilation, we hypothesized that elevated circulating EP could contribute to the vasodilation that occurs in septic patients. MATERIALS AND METHODS: Blood for measurement of EP was collected from not-septic and septic patients admitted to the intensive care unit (ICU), as well as from healthy subjects. Plasma EP concentrations were measured using a competitive ELISA technique. RESULTS: The plasma EP level in the septic patients was approximately half that of the not-septic patients and the healthy controls, with similar EP levels in the latter two groups. There was no apparent association between EP levels and age or gender in any of the groups. CONCLUSIONS: Plasma EP levels were actually decreased in septic patients, possibly indicating that the balance between EP production vs. elimination favors elimination. This result further suggests that circulating EP may not be important in the development of the vasodilation and hypotension that occurs in septic shock. Alternatively, however, increased degradation of EP by elastase or other enzymes could lead to the appearance of biologically active EP, which may not be recognized by the ELISA assay. 相似文献