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11.
Sexual dimorphism in foot length proportionate to stature   总被引:1,自引:0,他引:1  
BACKGROUND: The preponderance of existing results suggests that, relative to stature, women have smaller feet than men. However, several investigations indicate that the relationship between foot length and stature may be curvilinear, a pattern that, due to the dimorphic nature of stature, would mask the true direction of pedal sexual dimorphism in published results. AIM: The study aimed to determine whether proportionate foot length is sexually dimorphic and, if so, the nature of that dimorphism. MATERIALS AND METHODS: Surveying genetically disparate populations (USA, Turkey, and Native North and Central American), we examined data from three previous anthropometric studies (Davis 1990, Parham et al. 1992, Ozaslan et al. 2003) and foot tracings from the Steggerda Collection at the US National Museum of Health and Medicine. Analyses explored sex differences in the ratio between foot length and stature, and tested for nonlinearity. RESULTS: Although varying in degree across populations, proportionate to stature, female foot length is consistently smaller than male foot length. CONCLUSION: Given the biomechanical challenges posed by pregnancy, smaller female proportionate foot length is somewhat surprising, as foot length affects dorsoventral stability. It is possible that the observed pattern reflects intersexual selection for small female foot size, a cue of youth and nulliparity.  相似文献   
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The feasibility and acceptability of cognitive behavior therapy for HIV-related peripheral neuropathic pain was examined and the potential efficacy of the intervention was compared with that of supportive psychotherapy in reducing pain, pain-related interference with functioning, and distress. Sixty-one patients were randomly assigned to receive six weekly sessions of cognitive behavior therapy or supportive psychotherapy. Thirty-three subjects completed the protocol. Both groups showed significant reductions in pain. The cognitive behavior group improved in most domains of pain-related functional interference and distress; the supportive psychotherapy group showed fewer gains. The high dropout rate suggests that psychotherapeutic treatments for HIV-related pain may have limited feasibility and acceptability.  相似文献   
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The US Food and Drug Administration approved a 6-month regimen of pretomanid, bedaquiline, and linezolid for extensively drug-resistant or multidrug-intolerant tuberculosis after a trial in South Africa demonstrated 90% effectiveness 6 months posttreatment. We report on a patient who completed the regimen using a lower linezolid dose.  相似文献   
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BACKGROUND: Genetic background has a major influence on the manifestation of multifactorial diseases such as hypertension in which severe complications may be caused through an interaction with additional factors, which may be genetically determined. We have previously described a genetic model of malignant hypertension (MH) in rats carrying the mouse Ren2 gene (TGRmRen2-27), in which the phenotype is dependent on the genetic background. METHODS: Using a single homozygous TGRmRen2-27 male as transgene donor, we produced two F1 populations with (a) 100% penetrance of MH in progeny heterozygous for the Fischer F344 genetic background and (b) 58.5% penetrance in progeny heterozygous for the Lewis genetic background. To identify the modifier loci affecting the phenotype, a cohort of 252 males was produced by breeding the same single male with Fischer-Lewis F1 females. The progeny were phenotyped for clinical and pathological features of MH. RESULTS: Genome-wide screening and quantitative trait loci (QTL) analysis identified two loci, on chromosome 10 (LOD 4.4) and on chromosome 17 (LOD 3.9) close to the Ace and At1 genes, respectively, which contribute to the lethal MH phenotype. Their influence on mortality was consistent with a multiplicative effect of the two loci. In addition, we found higher plasma angiotensin-converting enzyme activity in progeny receiving the Fischer allele than in progeny receiving the Lewis allele (123.5 +/- 9.5 vs. 91.8 +/- 4.9 U/liter, P < 0.01), suggesting the association of angiotensin-converting enzyme and MH. CONCLUSIONS: Our study demonstrates the application of a transgene as a "major gene" to facilitate the identification of modifier loci, which can affect the phenotype of MH, and reveals Ace and At1 as candidate genes involved in the manifestation of the MH phenotype.  相似文献   
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BACKGROUND: Many complaints of Gulf War veterans are compatible with a neurologic illness involving the basal ganglia. METHODS: In 12 veterans with Haley Gulf War syndrome 2 and in 15 healthy control veterans of similar age, sex, and educational level, we assessed functioning neuronal mass in both basal ganglia by measuring the ratio of N-acetyl-aspartate to creatine with proton magnetic resonance spectroscopy. Central dopamine activity was assessed by measuring the ratio of plasma homovanillic acid (HVA) and 3-methoxy-4-hydroxyphenlyglycol (MHPG). RESULTS: The logarithm of the age-standardized HVA/MHPG ratio was inversely associated with functioning neuronal mass in the left basal ganglia (R(2) = 0.56; F(1,27) = 33.82; P<.001) but not with that in the right (R(2) = 0. 04; F(1,26) = 1.09; P =.30). Controlling for age, renal clearances of creatinine and weak organic anions, handedness, and smoking did not substantially alter the associations. CONCLUSIONS: The reduction in functioning neuronal mass in the left basal ganglia of these veterans with Gulf War syndrome seems to have altered central dopamine production in a lateralized pattern. This finding supports the theory that Gulf War syndrome is a neurologic illness, in part related to injury to dopaminergic neurons in the basal ganglia.  相似文献   
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Background  

Environmental exposure to lead remains a significant health problem for children. The costs of lead exposure in children are estimated to be considerably more than other childhood diseases of environmental origin. While long-term trends in blood lead levels (BLLs) among children are declining, seasonal variation persists. Cross-sectional studies have found a peak in summer months. Part of this variation may be due to increased exposure to lead paint on window sills and through increased contact with soils containing lead during the summer. The current study represents the largest published population-based study on seasonality and trends in the BLLs of children to date. In addition, the results offer a comparison of recent data on seasonality of BLLs in New York State children, to studies conducted over the past three decades.  相似文献   
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