全文获取类型
收费全文 | 2751篇 |
免费 | 232篇 |
国内免费 | 47篇 |
专业分类
耳鼻咽喉 | 36篇 |
儿科学 | 113篇 |
妇产科学 | 58篇 |
基础医学 | 379篇 |
口腔科学 | 89篇 |
临床医学 | 243篇 |
内科学 | 652篇 |
皮肤病学 | 72篇 |
神经病学 | 237篇 |
特种医学 | 140篇 |
外科学 | 451篇 |
综合类 | 18篇 |
一般理论 | 3篇 |
预防医学 | 178篇 |
眼科学 | 51篇 |
药学 | 189篇 |
中国医学 | 24篇 |
肿瘤学 | 97篇 |
出版年
2023年 | 25篇 |
2022年 | 20篇 |
2021年 | 74篇 |
2020年 | 40篇 |
2019年 | 76篇 |
2018年 | 70篇 |
2017年 | 74篇 |
2016年 | 57篇 |
2015年 | 67篇 |
2014年 | 80篇 |
2013年 | 93篇 |
2012年 | 153篇 |
2011年 | 157篇 |
2010年 | 111篇 |
2009年 | 84篇 |
2008年 | 138篇 |
2007年 | 179篇 |
2006年 | 159篇 |
2005年 | 130篇 |
2004年 | 101篇 |
2003年 | 109篇 |
2002年 | 115篇 |
2001年 | 81篇 |
2000年 | 104篇 |
1999年 | 63篇 |
1998年 | 36篇 |
1997年 | 33篇 |
1996年 | 41篇 |
1995年 | 30篇 |
1994年 | 28篇 |
1993年 | 13篇 |
1992年 | 51篇 |
1991年 | 49篇 |
1990年 | 37篇 |
1989年 | 36篇 |
1988年 | 27篇 |
1987年 | 28篇 |
1986年 | 29篇 |
1985年 | 20篇 |
1984年 | 15篇 |
1983年 | 12篇 |
1981年 | 16篇 |
1979年 | 18篇 |
1978年 | 10篇 |
1975年 | 9篇 |
1972年 | 12篇 |
1970年 | 14篇 |
1969年 | 13篇 |
1968年 | 14篇 |
1966年 | 9篇 |
排序方式: 共有3030条查询结果,搜索用时 15 毫秒
101.
Hillian AD Londono D Dunn JM Goddard KA Pace RG Knowles MR Drumm ML;CF Gene Modifier Study Group 《Genes and immunity》2008,9(6):501-508
Cystic fibrosis pulmonary disease is characterized by excessive and prolonged inflammation. CF Pulmonary disease severity exhibits considerable variation that, to some extent, appears to be due to the presence of modifier genes. Several components of the inflammatory response are known to have altered regulation in the CF lung. Genetic variants in 52 inflammatory genes were tested for associations with lung disease indices in a CF patient population (n=737) homozygous for the DeltaF508 cystic fibrosis transmembrane conductance regulator mutation. Variants in three inflammatory genes showed significant genotypic associations with CF lung disease severity, including IL8 and previously reported TGFbeta1 (P< or =0.05). When analyzed by gender, it was apparent that IL8 variant associations were predominantly due to males. The IL8 variants were tested in an additional CF population (n=385) and the association in males verified (P< or =0.01). The IL8 variants were in strong linkage disequilibrium with each other (R2> or =0.82), while variants in neighboring genes CXCL6, RASSF6 and PF4V1 did not associate (P> or =0.26) and were in weaker LD with each other and with the IL8 variants (0.01< or =R2< or =0.49). Studies revealed differential expression between the IL8 promoter variant alleles (P<0.001). These results suggest that IL8 variants modify CF lung disease severity and have functional consequences. 相似文献
102.
J.A. Boga M. de Oa A. Fernndez-Verdugo D. Gonzlez A. Morilla M. Arias L. Barreiro F. Hidalgo S. Meln 《Journal of clinical virology》2008,42(4):425-428
BACKGROUND: In spite of universal vaccination, several sporadic cases of mumps infection, which could produce outbreaks, are detected every year in different countries. OBJECTIVE: Mumps virus strains causing two regional outbreaks in Asturias (Spain) were phylogenetically characterized. STUDY DESIGN: Mumps virus strains, which were detected in samples from patients belonging to two regional outbreaks in Asturias, were characterized by sequencing of the SH gene and further alignment to homologous sequences of representative strains of the different mumps genotypes. RESULTS: Two different strains (Ast/SP02 and Ast/SP07) were isolated. Sequence analysis revealed that while Ast/SP02 belonged to genotype H, Ast/SP07 was phylogenetically close to UK02-19, a reference strain for a new genotype. Both strains belonged to different genotypes from those used in the vaccination (Jeryl-Lynn strain is genotype A). CONCLUSION: Mumps virus strains different from those used in vaccination program can cause mumps outbreaks even in vaccinated patients. 相似文献
103.
Rotavirus diarrhea severity is related to the VP4 type in Mexican children 总被引:6,自引:0,他引:6 下载免费PDF全文
Mota-Hernández F Calva JJ Gutiérrez-Camacho C Villa-Contreras S Arias CF Padilla-Noriega L Guiscafré-Gallardo H de Lourdes Guerrero M López S Muñoz O Contreras JF Cedillo R Herrera I Puerto FI 《Journal of clinical microbiology》2003,41(7):3158-3162
This report is of a community-based case control study to assess whether the severity of acute diarrhea by rotavirus (RV) in young children is associated with a particular VP7 (G) or VP4 (P) RV serotype. Five hundred twenty children younger than 2 years of age with diarrhea lasting less than 3 days were age and gender matched with 520 children with no diarrhea. The G and P serotypes were determined with specific monoclonal antibodies, and the VP4 serotype specificity in a subgroup was confirmed by genotyping. Infection with a G3 serotype led to a higher risk of diarrhea than infection with a G1 serotype. Infection with a G3-nontypeable-P serotype was associated with more severe gastroenteritis than infection with a G3 (or G1) P1A[8] serotype. A child with diarrhea-associated dehydration was almost five times more likely to be infected with a G3-nontypeable-P serotype than a child without dehydration (P < 0.001). Moreover, the two predominant monotypes within serotype P1A[8] had significantly different clinical manifestations. In this study, the severity of RV-associated diarrhea was related to different P serotypes rather than to G serotypes. The relationship between serotype and clinical outcomes seems to be complex and to vary among different geographic areas. 相似文献
104.
Gopeshwar Narayan Luigi Scotto Vijayalakshmi Neelakantan Sherine H. Kottoor Ada Ho Yan Wong Shee‐Loong Loke Mahesh Mansukhani Bhavana Pothuri Jason D. Wright Andreas M. Kaufmann Achim Schneider Hugo Arias‐Pulido Qian Tao Vundavalli V. Murty 《Genes, chromosomes & cancer》2009,48(11):983-992
Cervical cancer (CC) is the second most common cancer in women. Currently, no tractable molecular‐based therapeutic targets exist for patients with invasive CC and no predictive markers of risk assessment for progression of precancerous lesions are identified. New molecular insights into CC pathogenesis are urgently needed. Towards this goal, we first determined the copy number alterations of chromosome 4 and then examined the role of PCDH10 mapped to 4q28 as a candidate tumor suppressor gene. We identified monosomy 4 in 47% of 81 invasive CC studied by SNP array and found that 91% of 130 invasive CC harboring methylation in the promoter region of the PCDH10 gene. We then showed that aberrant promoter hypermethylation of PCDH10 is associated with downregulation of gene expression and cell lines exposed to demethylating agent resulted in profound reactivated gene expression. We also showed that the promoter methylation in the PCDH10 gene occurs at an earliest identifiable stage of low‐grade squamous intraepithelial lesion. Our studies demonstrate that inactivation of PCDH10 may be a critical event in CC progression and form a potentially useful therapeutic target for CC. © 2009 Wiley‐Liss, Inc. 相似文献
105.
106.
Eugenia Arias Horacio Martinetto Marcelo Schultz Sebastian Ameriso Santiago Rivera Oscar Lossetti Gustavo Sevlever 《Diagnostic molecular pathology》2006,15(3):174-179
A polymerase chain reaction (PCR) method for the detection of the glmM gene, selected as Helicobacter pylori target sequence, was improved. While performing pathogenicity island cagA gene detection to discriminate pathogenic strains in atherosclerotic carotid samples, several cagA-positive but glmM-negative samples were found. Polymorphisms present in the region amplified in the nested PCR reaction could explain this result; primers were therefore designed to perform a seminested reaction; this modification optimized sensitivity while maintaining specificity. A real-time PCR for Helicobacter DNA detection was also setup. The combination of all 4 PCR reactions detected 83% of H. pylori DNA-positive samples in atherosclerotic carotid tissue, 64% of which were cagA gene positive. 相似文献
107.
108.
Prognostic impact of chromosomal translocations in myelodysplastic syndromes and chronic myelomonocytic leukemia patients. A study by the spanish group of myelodysplastic syndromes 下载免费PDF全文
Meritxell Nomdedeu Xavier Calvo Arturo Pereira Anna Carri Francesc Sol Elisa Luo Jos Cervera Teresa Vallespí Concha Muoz Cndida Gmez Amparo Arias Esperanza Such Guillermo Sanz Javier Grau Andrs Insunza María‐Jos Calasanz María‐Teresa Ardanaz Jesús‐María Hernndez‐Rivas Gemma Azaceta Sara lvarez Joaquín Snchez María‐Luisa Martín Joan Bargay Valle Gmez Carlos‐Javier Cervero María‐Jos Allegue Rosa Collado Elías Campo Jordi Esteve Benet Nomdedeu Dolors Costa 《Genes, chromosomes & cancer》2016,55(4):322-327
Chromosomal translocations are rare in the myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML). With the exception of t(3q), translocations are not explicitly considered in the cytogenetic classification of the IPSS‐R and their impact on disease progression and patient survival is unknown. The present study was aimed at determining the prognostic impact of translocations in the context of the cytogenetic classification of the IPSS‐R. We evaluated 1,653 patients from the Spanish Registry of MDS diagnosed with MDS or CMML and an abnormal karyotype by conventional cytogenetic analysis. Translocations were identified in 168 patients (T group). Compared with the 1,485 patients with abnormal karyotype without translocations (non‐T group), the T group had a larger proportion of patients with refractory anemia with excess of blasts and higher scores in both the cytogenetic and global IPSS‐R. Translocations were associated with a significantly shorter survival and higher incidence of transformation into AML at univariate analysis but both features disapeared after multivariate adjustment for the IPSS‐R cytogenetic category. Patients with single or double translocations other than t(3q) had an outcome similar to those in the non‐T group in the intermediate cytogenetic risk category of the IPSS‐R. In conclusion, the presence of translocations identifies a subgroup of MDS/CMML patients with a more aggressive clinical presentation that can be explained by a higher incidence of complex karyotypes. Single or double translocations other than t(3q) should be explicitly considered into the intermediate risk category of cytogenetic IPSS‐R classification. © 2015 Wiley Periodicals, Inc. 相似文献
109.
110.
AIMS AND BACKGROUND: Protein O-linked glycosylation is regulated in vivo by the concentration of hexosamine substrates. Calorie restriction (60% of ad libitum intake) for 20 days causes decreased UDP-N-acetylhexosamine levels and increased insulin-mediated glucose transport in rat skeletal muscle. Conversely, prolonged incubation (19 h) of muscle with O-(2-acetamido-2-deoxy-D-glucopyranosylidene)amino-N-phenyl-carbamate (PUGNAc; an inhibitor of N-acetyl-beta-D-glucosaminidase) is characterized by increased O-linked glycosylation and insulin resistance. We aimed to determine the calorie restriction effect on O-linked glycosylation and characterize the temporal relationship between PUGNAc-induced O-linked glycosylation and insulin resistance. HYPOTHESIS: A calorie restriction protocol characterized by decreased muscle hexosamine levels will result in a global reduction in O-linked glycosylated proteins in muscle, and PUGNAc-induced insulin resistance will coincide with increased O-linked glycosylation. METHODS: Plantaris muscle and liver from rats (ad libitum or calorie restricted) were analysed for O-linked glycosylation using two antibodies against different O-linked N-acetylglucosamine epitopes. Also, rat epitrochlearis muscles were incubated for 8.5 h +/- 100 mum PUGNAc prior to measurement of [(3)H]-3-O-methylglucose transport and O-linked glycosylation. RESULTS: Calorie restriction did not alter protein O-linked glycosylated levels in muscle or liver. Incubation with PUGNAc for 8.5 h resulted in increased in O-linked glycosylation but unaltered basal or insulin-stimulated glucose transport. CONCLUSIONS: The delay between O-linked glycosylation and insulin resistance in muscle incubated with PUGNAc suggests an indirect, relatively slow mechanism for insulin resistance. The effect of calorie restriction on insulin action in muscle is unlikely to be the direct result of a global change in protein O-linked glycosylation. 相似文献