全文获取类型
收费全文 | 1232篇 |
免费 | 73篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 28篇 |
妇产科学 | 17篇 |
基础医学 | 169篇 |
口腔科学 | 36篇 |
临床医学 | 89篇 |
内科学 | 338篇 |
皮肤病学 | 44篇 |
神经病学 | 137篇 |
特种医学 | 18篇 |
外科学 | 94篇 |
综合类 | 10篇 |
预防医学 | 123篇 |
眼科学 | 10篇 |
药学 | 83篇 |
中国医学 | 6篇 |
肿瘤学 | 91篇 |
出版年
2024年 | 1篇 |
2023年 | 23篇 |
2022年 | 5篇 |
2021年 | 46篇 |
2020年 | 34篇 |
2019年 | 60篇 |
2018年 | 70篇 |
2017年 | 37篇 |
2016年 | 50篇 |
2015年 | 37篇 |
2014年 | 40篇 |
2013年 | 78篇 |
2012年 | 129篇 |
2011年 | 136篇 |
2010年 | 53篇 |
2009年 | 38篇 |
2008年 | 102篇 |
2007年 | 72篇 |
2006年 | 61篇 |
2005年 | 73篇 |
2004年 | 61篇 |
2003年 | 55篇 |
2002年 | 27篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1996年 | 2篇 |
1995年 | 3篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1983年 | 1篇 |
1977年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有1309条查询结果,搜索用时 15 毫秒
71.
72.
73.
G12S and H50R variations are polymorphisms in the SDHD gene 总被引:1,自引:0,他引:1
Cascón A Ruiz-Llorente S Cebrián A Letón R Tellería D Benítez J Robledo M 《Genes, chromosomes & cancer》2003,37(2):220-221
74.
Role of follicle-stimulating hormone receptor Ser680Asn polymorphism in the efficacy of follicle-stimulating hormone 总被引:22,自引:0,他引:22
de Castro F Ruiz R Montoro L Pérez-Hernández D Sánchez-Casas Padilla E Real LM Ruiz A 《Fertility and sterility》2003,80(3):571-576
OBJECTIVE: To evaluate the association between FSH efficacy and FSHR alleles. DESIGN: Retrospective study. SETTING: University-based fertility unit and a private center for biomedical research. PATIENT(S): One hundred two women with ovarian function who were undergoing controlled ovarian stimulation (COS). Women were categorized as poor responders (< or =3 ovarian follicles at the end of the cycle) or normal responders (>3 follicles). INTERVENTION(S): Daily administration of exogenous FSH. MAIN OUTCOME MEASURE(S): Number of good or poor responders. RESULT(S): The allele frequency and genotype distribution of the Ser680Asn marker differed significantly between groups. Cycle cancellations were increased (21%) among women who were homozygous for Ser680 compared with Ser/Asn and Asn/Asn patients, and 36% of poor-responders were homozygous for Ser680. CONCLUSION(S): The results support a role for FSHR gene in COS outcome. However, the weight of this factor is probably low. The Ser680 allele may act in concert with other environmental and genetic factors that contribute to FSH efficacy. 相似文献
75.
Vallés J Mesalles E Mariscal D del Mar Fernández M Peña R Jiménez JL Rello J 《Intensive care medicine》2003,29(11):1981-1988
Objective To examine the characteristics, prognostic factors, and outcome of patients with severe hospital-acquired pneumonia admitted to the ICU.Design and setting Prospective observational clinical study in two medical-surgical ICUs with 16 and 20 bedsPatients and participants During a 7-year period all hospitalized patients requiring admission to either ICU for hospital-acquired pneumonia were followed up.Measurements and results We diagnosed 96 episodes of severe hospital-acquired pneumonia, and in 67 cases a causal diagnosis was made. Most episodes were late-onset pneumonia. Gram-negative micro-organisms were isolated in 51% of episodes diagnosed, and Pseudomonas aeruginosa was the most frequent pathogen isolated (24%). Clearly significant variations happened between hospitals, particularly affecting the incidence of Aspergillus spp. and Legionella pneumophila. Forty-nine patients developed septic shock (51%). Fifty-one patients died (53%). Aspergillosis and pneumonia due to P. aeruginosa were associated with the highest mortality. Septic shock (OR: 14.27) and chronic obstructive pulmonary disease (OR: 6.11) were independently associated with a poor prognosis.Conclusions Patients with severe hospital-acquired pneumonia admitted to the ICU present high mortality. The presence of septic shock and chronic obstructive pulmonary disease in conjunction with specific microorganisms are associated with a poor prognosis. Local epidemiological data combined with a patient-based approach may allow a more accurate therapy decision making. 相似文献
76.
Sancho R Lucena C Macho A Calzado MA Blanco-Molina M Minassi A Appendino G Muñoz E 《European journal of immunology》2002,32(6):1753-1763
Capsiate and its dihydroderivatives are the major capsaicinoids of sweet pepper. These new capsaicinoids do not activate the vanilloid receptor type 1 (VR1) but they share with capsaicin (CPS)some biological activities mediated in a VR1-independent fashion. In this study we show that CPS and nordihydrocapsiate (CPT) inhibit early and late events in T cell activation, including CD69, CD25 and ICAM-1 cell surface expression, progression to the S phase of the cell cycle and proliferation in response to TCR and CD28 co-engagement. Moreover, both CPS and CPT inhibit NF-kappaB activation in response to different agents including TNF-alpha. CPS itself does not affect the DNA-binding ability of NF-kappaB but it prevents IkappaB kinase activation and IkappaBalpha degradation in a dose-dependent manner, without inhibiting the activation of the mitogen-activated protein kinases, p38, extracellular regulated kinase and c-Jun N-terminal protein kinase. Moreover, intraperitoneal pretreatment with CPT prevented mice from lethal septic shock induced by lipopolysaccharide. In a second model of inflammation CPT pretreatment greatly reduced the extensive damage in the glandular epithelium observed in the bowel of DSS-treated mice. Taken together, these results suggest that CPT and related synthetic analogues target specific pathways involved in inflammation, and hold considerable potential for dietary health benefits as well as for pharmaceutical development. 相似文献
77.
78.
Barrera Saldaña H Martínez Garza S Ortiz López R 《Revista de investigación clínica; organo del Hospital de Enfermedades de la Nutrición》2003,55(2):128-137
Cancer is considered a genetic disease, being classified as an accumulative somatic disorder aside of the Mendelian diseases, the chromosomopaties and the multifactorial diseases. It has been demonstrated in several human cancers that specific mutations in some genes are related to hystopathologic features and tumor progression. Thereby, mutations represent potentially valuable markers in disease-stage detection and evaluation. Mutations associated with neoplasia development and evolution are very valuable, and the related genes are classified as: oncogenes, tumor suppressing genes, DNA repairing genes and cell cycle regulator genes. The factability to determine and characterize these genes and relate them with one or several steps of tumorogenesis, makes them molecular markers that let us predict risk, make an early diagnosis, confirm a diagnosis, establish prognosis, guide the therapy and determine resistance to treatments. Molecular methods used today for analysis of this markers offer great advantages: they are vary sensitive, use a small sample, are fast, can be easily automated, are easily interpreted, allows quantitations and, very importantly, they become cheaper when a large quantity of samples are handled. In this review we mention some types of cancers and molecular methods that can be used to take advantage of their biomarkers. 相似文献
79.
López-Saucedo C Cerna JF Villegas-Sepulveda N Thompson R Velazquez FR Torres J Tarr PI Estrada-García T 《Emerging infectious diseases》2003,9(1):127-131
We developed and tested a single multiplex polymerase chain reaction (PCR) that detects enterotoxigenic, enteropathogenic, enteroinvasive, and Shiga toxin-producing Escherichia coli. This PCR is specific, sensitive, and rapid in detecting target isolates in stool and food. Because of its simplicity, economy, and efficiency, this protocol warrants further evaluation in large, prospective studies of polymicrobial substances. 相似文献
80.
Del Rocío Nieto-Martínez M Maupomé G Barceló-Santana F 《Journal of oral rehabilitation》2001,28(12):1094-1100
Gingival retraction cords are useful clinical aids but little information is available regarding desirable physical features that would preserve their integrity under tensile forces. The study aimed to establish under experimental conditions the extent to which tensile strength is affected by variation in cord diameter; impregnation with ferric sulphate (FS) or aluminium sulphate (AS); and cord hydration (wet/dry). Commercial cords and standard cotton cords were assayed in an Instron 1137 machine. Data were analysed using t-test, and one- and four-way ANOVA. Results indicated that tensile strength for 200 commercial cords was 1.4950 +/- 1.032 kg; and for 560 cotton cords was 1.2964 +/- 1.4560 kg. Cord hydration had no significant effect on tensile strength, whereas impregnation with AS or FS, a smaller diameter, and/or being a cotton cord decreased tensile strength (P < 0.001). Bivariate analyses showed that hydrated commercial cords had higher tensile strength than dry specimens; hydrated or dry cotton cords were not different. The FS-impregnated cotton cords had lower tensile strength than AS-impregnated or control cords, and the effect was greater at higher FS concentrations. This study is one of the first evaluations of the physical properties of cords, highlighting characteristics that may minimize the risk of tearing. 相似文献