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31.
We examined putative autonomic and hemodynamic mechanisms that might explain our prior finding that cardiorespiratory fitness mitigates blood pressure responses by normotensive women during the hand cold pressor test. We report that fitness level was inversely related to increases in systolic and diastolic blood pressures and muscle sympathetic nerve activity (MSNA) during the cold pressor among women but not men. The pattern of responses among fitter women was consistent with decreased central sympathetic outflow resulting in reduced stroke volume or dampened peripheral resistance in vascular beds other than calf skeletal muscle. Fitter men and women had slightly larger increases in blood pressure during mental arithmetic, but otherwise fitness was not directly related to stress responses. The results further encourage consideration of cardiorespiratory fitness as a modifying covariate when the hand cold pressor test is used as a predictor of future hypertension among women. 相似文献
32.
Analysis of human papillomavirus prevalence and TP53 polymorphism in head and neck squamous cell carcinomas 总被引:1,自引:0,他引:1
Cortezzi SS Provazzi PJ Sobrinho JS Mann-Prado JC Reis PM de Freitas SE Filho JF Fukuyama EE Cordeiro JA Cury PM Maniglia JV Villa LL Tajara EH Rahal P 《Cancer Genetics and Cytogenetics》2004,150(1):44-49
Head and neck squamous cell carcinoma is a disease associated with tobacco and alcohol abuse. There is evidence that the oncogenic human papillomavirus (HPV) may also be a risk for upper aerodigestive tract cancers. High-risk HPVs encode two early proteins, E6 and E7, that can bind to p53 and pRb, respectively, and induce its degradation or inactivation. The TP53 gene has a single polymorphism at codon 72 of exon 4 that encodes either arginine (Arg) or proline (Pro). The purpose of this study was to evaluate the role of HPV infection and TP53 polymorphism in head and neck cancer. We analyzed 50 tumors, as well swabs of oral mucosa from 142 control individuals, with a polymerase chain reaction technique. The prevalence of HPV in controls was 10.6% and in cancer specimens 16%. The frequency distribution of genotypes in controls was 50% Arg/Arg, 43% Arg/Pro and 7% Pro/Pro; in tumors, it was 52% Arg/Arg, 32% Arg/Pro, and 16% Pro/Pro. Contrary to the results of some studies on cervical cancer, no association between any TP53 genotype or allele and the development of head and neck cancer was observed, regardless of HPV status, except for the Pro/Pro genotype, which is associated with the absence of HPV. The arginine allele appears to protect against head and neck cancers. Also, the data showed that HPV infection results in no increased risk of developing head and neck tumors. 相似文献
33.
Erica di Martino Laura J Hardie Christopher P Wild Yun Y Gong Joanna R Olliver Martin D Gough Nigel C Bird 《Genetics in medicine》2007,9(6):341-347
PURPOSE: The role of genetic susceptibility to esophageal adenocarcinoma and its precursor lesion Barrett esophagus has not been fully elucidated. This study investigated the effect of polymorphisms in the manganese superoxide dismutase (MnSOD) and NAD(P)H:quinone oxidoreductase 1 (NQO1) genes in modulating the risk of developing Barrett esophagus or esophageal adenocarcinoma. METHODS: A total of 584 patients (146 esophagitis, 200 Barrett esophagus, 144 esophageal adenocarcinoma, and 94 controls) were genotyped for the MnSOD C14T and NQO1 C609T polymorphisms using polymerase chain reaction and restriction fragment length polymorphism analysis. RESULTS: The NQO1 TT genotype was less common in Barrett esophagus (2.0%) and esophageal adenocarcinoma (1.4%) patients, compared with both esophagitis patients (7.6%) and controls (5.4%). After adjustment for sex, age, body mass index, reflux symptoms, and smoking status, patients with the homozygous TT genotype had a 4.5-fold decreased risk of developing Barrett esophagus (odds ratio = 0.22, 95% confidence interval = 0.07-0.76, P = 0.01) and a 6.2-fold decreased risk of esophageal adenocarcinoma (odds ratio = 0.16, 95% confidence intervals = 0.03-0.94, P = 0.04) compared with individuals with the TC and CC genotypes. No significant differences between groups were observed for the MnSOD polymorphism (P = 0.289). CONCLUSIONS: Overall, the results of this study suggest that the NQO1 TT genotype may offer protection from reflux complications such as Barrett esophagus and esophageal adenocarcinoma. 相似文献
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We report a case of mantle cell lymphoma histologically indistinguishable from marginal zone lymphoma. An 83-year-old man presented with a 9.0-cm, slowly enlarging axillary mass. Microscopically, the neoplastic process was largely interfollicular, surrounding residual follicular centers, some of which had discernible small lymphocyte mantles. Overall, the morphologic pattern was highly suggestive of marginal zone lymphoma. However, flow cytometric and immunohistochemical results, including cyclin D1 positivity, revealed an immunophenotype that fit with mantle cell lymphoma. The differential diagnosis of mantle cell lymphoma is broad, and it is well known that mantle cell lymphoma can assume a number of histologic appearances, including, infrequently, that of more indolent B-cell non-Hodgkin lymphomas. Although not pathognomonic, cyclin D1 positivity is highly specific for mantle cell lymphoma and is key in distinguishing these clinically dissimilar malignant lymphomas. In recent years, detection of cyclin D1 has expanded the recognizable histologic spectrum of mantle cell lymphoma. 相似文献
36.
Hernandez Natalie D. Francis Sherilyn Allen Morgan Bellamy Erica Sims Omar T Oh Hyejung Guillaume Dominique Parker Andrea Chandler Rasheeta 《Maternal and child health journal》2022,26(4):770-777
Maternal and Child Health Journal - Data are scarce regarding the prevalence and predictors of perinatal mood and anxiety disorders (PMADs) among Black women. The purpose of this study was to... 相似文献
37.
BackgroundIndividuals’ perceptions of their fecundity, or biological ability to bear children, have important implications for health behaviors, including infertility help-seeking and contraceptive use. Little research has examined these perceptions among U.S. women.MethodsThis cross-sectional study examines perceptions of one's own fecundity among U.S. women aged 24 to 32 who participated in the 2009–2011 rounds of the National Longitudinal Survey of Youth (1997) cohort. Analyses were limited to 3,088 women who indicated that they or their partners never received a doctor's diagnosis regarding fertility difficulties.ResultsOf the women in the sample, 67% perceived their hypothetical chances of becoming pregnant as very likely; the remainder perceived their chances as somewhat likely (13%), not as likely (15%), or provided a “don't know” response (6%). Twenty-six percent of Black women and 19% of Latina women perceived themselves as not very likely to become pregnant, compared with only 12% among non-Black/non-Latina women (p < .001). Only 6% of women with a college degree perceived their chances of becoming pregnant as not very likely, compared with 36% among women without a high school degree (p < .001). Racial/ethnic and educational differences persisted in fully adjusted models. Other factors associated with fecundity self-perceptions include partnership status, parity, fertility expectations, sexual activity, prolonged exposure to unprotected intercourse for at least 6 and/or 12 months without becoming pregnant, and self-rated health.ConclusionsFindings indicate that self-perceived fecundity differs systematically by demographic and other characteristics. This phenomenon should be investigated further to understand how it may influence disparities in health behaviors and outcomes. 相似文献
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Isabel Beshar Jodi So Meena Chelvakumar Erica P. Cahill Kate A. Shaw Jonathan G. Shaw 《Contraception》2021,103(4):246-254