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The HLA-DRB1 and -DQB1 alleles in 161 healthy unrelated individuals, including Caucasians, Blacks and Mulattos (mixed Caucasian and Black), from the Northeastern region of the state of S?o Paulo, Brazil were analysed. The 36 different DRB1 alleles detected included not only common Caucasian alleles, but also DRB1*0411, 0807 and 1402, typical of Amerindians, and DRB1*0302, 1503, and 0804, typical of African American Blacks.  相似文献   
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BackgroundObesity has reached epidemic proportions worldwide, affecting life quality and span. Susceptibility to obesity is partly mediated by genetic differences. Indeed, several genes from the clock gene family have already been shown to be intimately associated with obesity in diverse ethnic groups. In the present study, an association between BMI and the rs707467, rs228697 and rs228729 PER3 (Period Circadian Clock 3) polymorphisms in subjects with class II (BMI ≥ 35.0–39.9 kg/m2) and class III obesity (>40 kg/m2, extreme obesity) were carried out using TaqMan real-time PCR. Overall, 259 Brazilian adults were genotyped, of whom 122 had class II or III obesity (BMI ≥ 35.0 kg/m2) and 137 were controls having normal weight (BMI > 18.5 and <24.9 kg/m2).ResultsPER3 tag SNP (rs228729) shows a significant association with extreme obesity (1000 permutation p = 0.03 and p = 0.04), for genotype and allele frequency respectively) and a haplotype among the three assessed SNPs (alleles G/T/A, rs228697, rs228729, and rs707467, respectively, 1000 permutation p = 0.03) was significantly more prevalent in the group with obesity.ConclusionThis exploratory association study suggests that PER3 rs228729 may be associated with extreme obesity in Brazilian adults, however, replication is needed.  相似文献   
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We obtained the complete sequence of a novel poxvirus, tentatively named Brazilian porcupinepox virus, from a wild porcupine (Coendou prehensilis) in Brazil that had skin and internal lesions characteristic of poxvirus infection. The impact of this lethal poxvirus on the survival of this species and its potential zoonotic importance remain to be investigated.  相似文献   
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Panels composed of Single Nucleotide Polymorphisms (SNPs) in genes related to pigmentation, when associated with different phenotypes, may assist in predicting the physical appearance of an individual, being very useful in forensic caseworks. We evaluated the association of seven OCA2-HERC2 SNPs and haplotypes with pigmentation characteristics (eye, skin, hair and freckles) in the highly admixed and phenotypically heterogeneous Brazilian population. All the seven SNPs evaluated presented one allele associated with phenotypes from at least two pigmentation features and the alternative allele associated with the opposite phenotypes from the same trait. The genotypic associations followed the same pattern for all seven SNPs. Nine haplotypes were observed in our sample and eight were associated with at least two pigmentation traits. Such SNPs and haplotypes could be deemed as good predictors for the presence of freckles and for skin, eye and hair pigmentation in the Brazilian population.  相似文献   
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Mosquito nets treated with long-lasting insecticide (LLINs), when used in compliance with guidelines of the World Health Organization, may be effective for malaria vector control. In 2012, approximately 150,000 LLINs were installed in nine municipalities in the state of Rondônia. However, no studies have assessed their impact on the reduction of malaria incidence. This study analyzed secondary data of malaria incidence, in order to assess the impact of LLINs on the annual parasite incidence (API). The results showed no statistically significant differences in API one year after LLIN installation when compared to municipalities without LLINs. The adoption of measures for malaria vector control should be associated with epidemiological studies and evaluations of their use and efficiency, with the aim of offering convincing advantages that justify their implementation and limit malaria infection in the Amazon Region.  相似文献   
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PurposeTo assess public preferences and perceptions regarding negative chest radiograph reports.MethodsUsing Amazon Mechanical Turk (Amazon Inc, Seattle, Washington), paid US English-speaking volunteers completed an 18-question survey. Participants were presented with the same two chest radiograph reports—one each in a freestyle and structured format—but randomized to one of four impression statements commonly used in our community. Participants were asked about content comprehension and confidence in the hypothetical interpreting radiologist.ResultsOver 15 days, 5,155 eligible participants completed the survey (of 6,363 respondents). Most reported prior chest radiography (68.9%) or any imaging (93.8%). Of those who underwent chest radiography, 77.6% reviewed their reports. Participants indicated structured reports were easier to comprehend (P < .001) but no difference in perceived confidence in the radiologist with freestyle versus structured reports (P = .21). No differences in comprehension were noted between different impressions with either freestyle (P = .077) or structured (P = .083) reports. Participants indicated higher confidence in radiologists when structured reports indicated “no acute disease” versus “unremarkable” (P = .049). When impressions stated “no acute disease,” participants indicated they would be more likely to do nothing, versus “negative chest” for which they indicated a higher likelihood of taking some action (P = .013, P = .04). Participant responses were similar for subgroups who previously underwent chest or other imaging and previously reviewed their imaging reports.ConclusionFor negative chest radiographs, structured reports are better comprehended by the public and less likely to prompt unnecessary follow-up. As patients increasingly access their medical records online, radiologist reporting should consider patient needs and behavior.  相似文献   
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BackgroundTo evaluate the association between periodontitis and interleukin-6 (IL6) -174 G/C polymorphism by data synthesis and subgroup analysis.MethodsEighteen case-control studies from 16 articles with 1616 cases and 1511 controls were included in this meta-analysis by searching the public databases including PubMed, Embase and Web of Science databases by Jun 2018. Data syntheses were performed using Stata 9.0.ResultsThere were inverse associations of IL6 -174 G/C polymorphism with both general periodontitis and overall periodontitis. In CC vs. GG inheritance model, whose effect was the most profound, the genetic polymorphism reduced the risks of general and overall periodontitis by 60% (95% CI = 0.25-0.65, P < 0.01) and 31% (95% CI = 0.38-0.97, P = 0.04) respectively. In addition, the G/C variation was likely to be protective against moderate (allele C vs. allele G: OR = 0.61, 95% CI = 0.43-0.87, P = 0.01; CC + GC vs. GG: OR = 0.57, 95% CI = 0.37-0.89, P = 0.01) and severe periodontitis (allele C vs. allele G: OR = 0.58, 95% CI = 0.41-0.84, P < 0.01; CC vs. GG: OR = 0.33, 95% CI = 0.13-0.82, P = 0.02) exclusively in Brazilian people. No reliable evidence was found regarding chronic periodontitis.ConclusionThis meta-analysis suggests that IL6 -174 G/C polymorphism may be negatively associated with risk of periodontitis.  相似文献   
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