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81.
82.
Emerging evidence suggests that host-microbe interaction in the cervicovaginal microenvironment contributes to cervical carcinogenesis, yet dissecting these complex interactions is challenging. Herein, we performed an integrated analysis of multiple “omics” datasets to develop predictive models of the cervicovaginal microenvironment and identify characteristic features of vaginal microbiome, genital inflammation and disease status. Microbiomes, vaginal pH, immunoproteomes and metabolomes were measured in cervicovaginal specimens collected from a cohort (n = 72) of Arizonan women with or without cervical neoplasm. Multi-omics integration methods, including neural networks (mmvec) and Random Forest supervised learning, were utilized to explore potential interactions and develop predictive models. Our integrated analyses revealed that immune and cancer biomarker concentrations were reliably predicted by Random Forest regressors trained on microbial and metabolic features, suggesting close correspondence between the vaginal microbiome, metabolome, and genital inflammation involved in cervical carcinogenesis. Furthermore, we show that features of the microbiome and host microenvironment, including metabolites, microbial taxa, and immune biomarkers are predictive of genital inflammation status, but only weakly to moderately predictive of cervical neoplastic disease status. Different feature classes were important for prediction of different phenotypes. Lipids (e.g. sphingolipids and long-chain unsaturated fatty acids) were strong predictors of genital inflammation, whereas predictions of vaginal microbiota and vaginal pH relied mostly on alterations in amino acid metabolism. Finally, we identified key immune biomarkers associated with the vaginal microbiota composition and vaginal pH (MIF), as well as genital inflammation (IL-6, IL-10, MIP-1α).  相似文献   
83.
Comparing the shapes of regression functions   总被引:1,自引:0,他引:1  
Heckman  NE; Zamar  RH 《Biometrika》2000,87(1):135-144
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84.
BackgroundTime to first cigarette (TTFC) after waking is an indicator of nicotine dependence. The association between TTFC and chronic obstructive pulmonary disease (COPD), the third leading cause of death in the United States, has not yet been reported.MethodsWe investigated the cross-sectional association between TTFC and prevalent COPD among 6,108 current smokers in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. COPD was defined as a self-reported diagnosis of emphysema, chronic bronchitis, or both. Current smokers in PLCO reported TTFC, the amount of time they typically waited before smoking their first cigarette of the day after waking, in four categories: ≤5, 6-30, 31-60, or >60 minutes. We used logistic regression models to investigate the association between TTFC and prevalent COPD with adjustments for age, gender, race, education, and smoking (cigarettes/day, years smoked during lifetime, pack-years, age at smoking initiation), and prior lung cancer diagnosis.ResultsCOPD was reported by 19% of these 6,108 smokers. Individuals with the shortest TTFC had the greatest risk of COPD; compared to those with the longest TTFC (>60 minutes) the adjusted odds ratios (OR) and 95% confidence intervals (CI) for COPD were 1.48 (95% CI, 1.15-1.91), 1.64 (95% CI, 1.29-2.08), 2.18 (95% CI, 1.65-2.87) for those with TTFC 31-60 minutes, 6-30 minutes, and ≤5 minutes, respectively (P-trend <0.0001). The association between TTFC and emphysema was similar to that for bronchitis, albeit the ORs were slightly stronger for chronic bronchitis; comparing TTFC ≤5 minutes to >60 minutes, the adjusted OR (95% CI) was 2.29 (1.69-3.12) for emphysema and 2.99 (1.95-4.59) for chronic bronchitis.ConclusionsCurrent smokers with shorter TTFC have increased risk of COPD compared to those with longer TTFC, even after comprehensive adjustment for established smoking covariates. Future epidemiologic studies, including prospective designs, should incorporate TTFC to better assess disease risk and evaluate the potential utility of TTFC as a COPD screening tool for smokers in the clinical setting.  相似文献   
85.
Previous studies indicated that dacarbazine and Temozolomide could be highly effective against refractory acute leukaemia. Their activity relies mainly on the generation of methyl adducts at the O(6)-position of guanine in DNA. High levels of O(6)-methylguanine-DNA methyltransferase (MGMT) or a defective mismatch repair (MMR) system, are associated with cellular resistance to triazenes. The MGMT inhibitor, O(6)-(4-bromothenyl)guanine (Lomeguatrib), can restore in vitro sensitivity to Temozolomide in MMR-proficient blasts. In the early 1970s we discovered that, in vivo, triazene compounds induce the appearance of novel transplantation antigens in murine leukaemia ("Chemical Xenogenization", CX). Non-self peptides presented by class I MHC molecules are generated by triazene-induced somatic mutations, affecting retroviral sequences that are detectable in the mouse genome. Moreover, preliminary experiments suggested that human cancer cells can also undergo CX. Therefore, we designed a chemo-immunotherapy strategy in leukaemic patients as follows: (a) cytoreduction and a hypothetical CX phase, i.e. treatment with Lomeguatrib (to suppress MGMT activity) and Temozolomide (to kill sensitive blasts and to presumably induce CX in resistant leukaemic cells); (b) immune response recovery phase using interleukin-2 (to possibly restore an immune response and take advantage of the hypothetical, triazene-induced CX). Here we present the results of pilot study which is in progress in patients with refractory/relapsed acute leukaemia. In all tested cases, Lomeguatrib suppressed MGMT activity in vivo. Six out of eight patients showed partial or complete disappearance of blast cells in peripheral blood or in bone marrow. We observed severe and long-lasting myelosuppression, accompanied by limited non-haematological toxicity. Up to now, two patients are alive (after 9 and 10 months, respectively), four died of opportunistic infections and two of progressive disease. This investigation confirms the potential role of triazenes in leukaemia and highlights the contribution of Lomeguatrib in overcoming drug resistance. Further studies are required to establish whether Temozolomide can induce CX in human leukaemia, and thus offer a new approach to control minimal residual disease.  相似文献   
86.
87.
Here we describe, the longest microbial time-series analyzed to date using high-resolution 16S rRNA tag pyrosequencing of samples taken monthly over 6 years at a temperate marine coastal site off Plymouth, UK. Data treatment effected the estimation of community richness over a 6-year period, whereby 8794 operational taxonomic units (OTUs) were identified using single-linkage preclustering and 21 130 OTUs were identified by denoising the data. The Alphaproteobacteria were the most abundant Class, and the most frequently recorded OTUs were members of the Rickettsiales (SAR 11) and Rhodobacteriales. This near-surface ocean bacterial community showed strong repeatable seasonal patterns, which were defined by winter peaks in diversity across all years. Environmental variables explained far more variation in seasonally predictable bacteria than did data on protists or metazoan biomass. Change in day length alone explains >65% of the variance in community diversity. The results suggested that seasonal changes in environmental variables are more important than trophic interactions. Interestingly, microbial association network analysis showed that correlations in abundance were stronger within bacterial taxa rather than between bacteria and eukaryotes, or between bacteria and environmental variables.  相似文献   
88.
1. The importance of native freshwater mussels for ecosystem processes depends on their density, size distribution and activity. In lakes, many of the factors that affect mussels (fish hosts, habitat, food) could be directly or indirectly related to wind‐driven physical processes. 2. We tested whether the abundance and size of Elliptio complanata in the shallow, nearshore areas of a medium‐sized lake were related to site exposure, substratum type and fish distribution. To disentangle some of the correlated variables known to affect mussel distribution, we used paired exposed and sheltered sampling sites along the 7‐km fetch of the lake basin. 3. The distribution of sediment characteristics in nearshore areas was highly predictable. The mean depth of accumulated soft sediments decreased with increasing fetch at wind‐exposed sites, but increased with increasing fetch at sheltered sites. Sediments were deeper along the main shoreline than around islands. Deeper sediments tended to be finer and higher in silt content and organic fraction. 4. The density and proportion of juvenile mussels along the main shoreline varied in a unimodal way with sediment depth. These results suggest that wind‐driven physical forces affect the transport of young juveniles to sediment depositional areas and create sediment conditions that influence their growth and survival. In contrast, the proportion of juvenile mussels around islands was not related to sediment characteristics, but decreased with remoteness of the island, suggesting that the distribution of juvenile mussels may be limited by fish movements. These results are tentative since they do not include buried juvenile mussels. 5. We also found a unimodal relationship between total mussel density (juveniles and adults) and sediment depth but, in contrast to the relationship for juveniles only, it applied to all sites with soft sediments, including islands. We conclude that factors related to sediment depth affect the growth and survival of adult mussels around islands and that these factors are strong enough to modify the pattern of distribution established via dispersal during earlier life stages. 6. The mean shell length of adults at different sites within the lake basin ranged from 60 to 85 mm. Mussel shell length decreased with increasing fetch at sites exposed to the prevalent winds, but was relatively constant on the sheltered side of peninsulas and islands. The size of unionid mussels in different parts of the lake seems to be determined both by their exposure to physical forces and by sediments. 7. The local distribution of E. complanata is determined, directly and indirectly, by wind‐driven forces. These processes are likely to be important for other benthic organisms affected by similar habitat conditions (e.g. sediment characteristics, physical disturbance).  相似文献   
89.

Background

Mood disorders may affect lung cancer risk. We evaluated this hypothesis in two large studies.

Methodology/Principal Findings

We examined 1,939 lung cancer cases and 2,102 controls from the Environment And Genetics in Lung cancer Etiology (EAGLE) case-control study conducted in Italy (2002–2005), and 82,945 inpatients with a lung cancer diagnosis and 3,586,299 person-years without a lung cancer diagnosis in the U.S. Veterans Affairs Inpatient Cohort (VA study), composed of veterans with a VA hospital admission (1969–1996). In EAGLE, we calculated odds ratios (ORs) and 95% confidence intervals (CI), with extensive adjustment for tobacco smoking and multiple lifestyle factors. In the VA study, we estimated lung cancer relative risks (RRs) and 95% CIs with time-dependent Poisson regression, adjusting for attained age, calendar year, hospital visits, time within the study, and related previous medical diagnoses. In EAGLE, we found decreased lung cancer risk in subjects with a personal history of mood disorders (OR: 0.59, 95% CI: 0.44–0.79, based on 121 lung cancer incident cases and 192 controls) and family history of mood disorders (OR: 0.62, 95% CI: 0.50–0.77, based on 223 lung cancer cases and 345 controls). The VA study analyses yielded similar results (RR: 0.74, 95% CI: 0.71–0.77, based on 2,304 incident lung cancer cases and 177,267 non-cancer person-years) in men with discharge diagnoses for mood disorders. History of mood disorders was associated with nicotine dependence, alcohol and substance use and psychometric scales of depressive and anxiety symptoms in controls for these studies.

Conclusions/Significance

The consistent finding of a relationship between mood disorders and lung cancer risk across two large studies calls for further research into the complex interplay of risk factors associated with these two widespread and debilitating diseases. Although we adjusted for smoking effects in EAGLE, residual confounding of the results by smoking cannot be ruled out.  相似文献   
90.
Pathway analysis of genome-wide association studies (GWAS) offer a unique opportunity to collectively evaluate genetic variants with effects that are too small to be detected individually. We applied a pathway analysis to a bladder cancer GWAS containing data from 3,532 cases and 5,120 controls of European background (n = 5 studies). Thirteen hundred and ninety-nine pathways were drawn from five publicly available resources (Biocarta, Kegg, NCI-PID, HumanCyc, and Reactome), and we constructed 22 additional candidate pathways previously hypothesized to be related to bladder cancer. In total, 1421 pathways, 5647 genes and ∼90,000 SNPs were included in our study. Logistic regression model adjusting for age, sex, study, DNA source, and smoking status was used to assess the marginal trend effect of SNPs on bladder cancer risk. Two complementary pathway-based methods (gene-set enrichment analysis [GSEA], and adapted rank-truncated product [ARTP]) were used to assess the enrichment of association signals within each pathway. Eighteen pathways were detected by either GSEA or ARTP at P≤0.01. To minimize false positives, we used the I2 statistic to identify SNPs displaying heterogeneous effects across the five studies. After removing these SNPs, seven pathways (‘Aromatic amine metabolism’ [PGSEA = 0.0100, PARTP = 0.0020], ‘NAD biosynthesis’ [PGSEA = 0.0018, PARTP = 0.0086], ‘NAD salvage’ [PARTP = 0.0068], ‘Clathrin derived vesicle budding’ [PARTP = 0.0018], ‘Lysosome vesicle biogenesis’ [PGSEA = 0.0023, PARTP<0.00012], ’Retrograde neurotrophin signaling’ [PGSEA = 0.00840], and ‘Mitotic metaphase/anaphase transition’ [PGSEA = 0.0040]) remained. These pathways seem to belong to three fundamental cellular processes (metabolic detoxification, mitosis, and clathrin-mediated vesicles). Identification of the aromatic amine metabolism pathway provides support for the ability of this approach to identify pathways with established relevance to bladder carcinogenesis.  相似文献   
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