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51.
Echocardiographic left ventricular mass (LVM) estimates are strong predictors of subsequent mortality and cardiovascular events. It is known that blood pressure (BP), weight (WT), and age are significantly correlated with LVM. We hypothesized that stroke volume (SV) measured by Doppler echocardiography would also be correlated with LVM. Two hundred and thirteen patients referred for routine echocardiography had determination of LVM, cuff BP, and Doppler SV. Those with localized LV disease, valvular disease, or cor pulmonale were excluded. In both men and women, systolic BP (SBP) was more closely correlated with LVM than was diastolic blood pressure or mean arterial pressure, and SV was more closely correlated with LVM than cardiac output or cardiac index. Stepwise regression, followed by multiple regression showed that four variables (WT, SV, SBP, and AGE) explained 32.3% of the variability in LVM in men and 48.5% of the variability in LVM in women. WT and SV were significant determinants of LVM in both men and women. Age was also significant in men and SBP was also significant in women. For both men and women, SV was more significantly correlated with LVM than was SBP. The changes in LVM associated with 1 SD increments of SV and SBP, respectively, were 8 and 5 g for men and 13 and 11 g for women. We conclude that men and women have different patterns of variables influencing LVM. Doppler echocardiographic SV is a newly described determinant of LVM that has a greater correlation with LVM than does SBP. This study reemphasizes the importance of WT as the major determinant of LVM. (ECHOCARDIOGRAPHY, Volume 13, January 1996)  相似文献   
52.

Background

Previous studies show sex-related differences in left ventricular (LV) response to exercise. It is not clear, however, whether these differences are also seen in younger healthy subjects.

Methods and Results

This study examined the changes in LV performance during dynamic upright exercise in 11 healthy men and 19 healthy young women according to the Bruce protocol and an individualized ramp protocol. There were no significant differences between the two protocols for either men or women in heart rate, blood pressure, LV ejection fraction (EF) (measured by ambulatory nuclear detector), and measured oxygen consumption. The peak oxygen consumption was higher in men than in women (44±13 vs 36±9 ml/kg/min; p<0.05), but the peak heart rate, systolic blood pressure, and EF were similar. The change in EF (from rest to exercise) was 19%±8% in men and 19%±11% in women with the Bruce protocol (difference not significant) and 26%±9% in men and 19%±6% in women with the ramp protocol (difference not significant). At peak exercise, both men and women showed an increase in end-diastolic volume (29%±14% vs 23%±11%; difference not significant) and a decrease in end-systolic volume (41%±15% vs 43%±21%) (difference not significant). The increase in cardiac output during exercise was due to an increase in heart rate and stroke volume in both men and women. At submaximal exercise, however, the decrease in end-systolic volume was less in women than in men (p<0.05).

Conclusions

There are no sex-related differences in compensatory mechanism during dynamic execise in healthy subjects. The changes in contractility and LV volume are not affected by the exercise protocol.  相似文献   
53.
Systemic administration of dopamine (DA) agonists markedly disrupts sensorimotor gating in rats as measured by prepulse inhibition (PPI) of the acoustic startle response. A qualitatively similar, but quantitatively weaker disruption of PPI follows DA infusion into the nucleus accumbens (NAC). The present study was designed to determine whether forebrain DA terminal fields other than the NAC contribute to the DAergic modulation of PPI. PPI was impaired significantly after infusion of DA (0–40 µg) into the NAC or anteromedial striatum, but not after DA infusion into the orbital cortex or posterolateral striatum. DA infusion into the amygdala also disrupted PPI, but this disruption was accompanied by a dose-dependent decrease in startle amplitude. These results suggest that DA overactivity in the both NAC and anteromedial striatum contribute to the gating-disruptive effects of systemically administered DA agonists, and that DA overactivity in mesocortical, mesoamygdaloid and non-limbic mesostriatal DA systems are not major substrates for a DAergic modulation of PPI.  相似文献   
54.
The hypothesis that special ability in mathematics is associated with a reduction in bias to dextral preference and skill was examined in several samples of students and in 97 male and 27 female teachers of mathematics, mainly in Universities and Polytechnics. The maths students and maths teachers differed from controls, both general and academic, in the direction predicted and several comparisons were statistically significant. Differences were in most cases clearer for males than females.An analysis of the findings in relation to the right shift (RS) theory of handedness (Annett, 1972, Annett, 1978) suggests that the incidence of left preference and skill is slightly raised in mathematicians not because of any intrinsic advantage of left preference but rather because extreme bias to the right, as expected in those carrying a hypothesised rs++ genotype, is disadvantageous for mathematical thinking. If the role of mathematics can be regarded as one of developing languages to describe those aspects of human experience which otherwise could be understood only in visuo-spatial images, it can be seen to require a coordination of those aspects of human intelligence which have been distinguished as depending differentially on the left and right cerebral hemispheres. The present findings suggest that this process might be impeded by a double dose of a gene which promotes left hemisphere language specialisation.  相似文献   
55.
Ethanol is an antagonist of the N-methyl-D-aspartate (NMDA) glutamate receptor. Ethanol dependence upregulates NMDA receptors and contributes to crosstolerance with selective NMDA receptor antagonists in animals. This study evaluated whether recovering ethanol-dependent patients show evidence of a reduced level of response to the effects of the NMDA receptor antagonist, ketamine. In this double-blind study, 34 recently detoxified alcohol-dependent patients and 26 healthy comparison subjects completed 3 test days involving a 40-min infusion of saline, ketamine 0.1 mg/kg, or ketamine 0.5 mg/kg in a randomized order. Recovering ethanol-dependent patients showed reduced perceptual alterations, dysphoric mood, and impairments in executive cognitive functions during ketamine infusion relative to the healthy comparison group. No attenuation of ketamine-induced amnestic effects, euphoria, or activation was observed. The alterations in NMDA receptor function observed in recovering ethanol-dependent patients may have important implications for ethanol tolerance, ethanol dependence, and the treatment of alcoholism.  相似文献   
56.
57.
Introduction. Breast cancer remains the most frecuent tumor among women in developed countries. The prognosis is linked to a great variety clinic and pathological factors. The objectives from this study are to identify markers related to survival of patients with primary diagnosis of breast cancer. Material and methods. We have reviewed the medical dossier from 2.227 consecutive women diagnosed for infiltrating breast cancer between January 1966 and december 2000 in a single institution. For statistic analysis we used 10.0 SPSS software. Results. In the univariate analysis, factors with the strongest predictive value for overall survival were: PEV, estrogene and progesterone receptors, TNM stage, lymphatic vessel involvement, histologic grade, Scarff differentiation and mitosis rate, elastosis, presence of histiocitosis, and the percentage of involved stage I and III lymph nodes (Berg clasification). In the multivariate analysis, 5 factors; progesterone receptors, Scarff mitotic rate, lymphatic vessel involvement, percentage of involved stage I lymph nodes, and presence of metastasis; were independent prognostic markers of survival. Conclusions. Many independent factors interact in the survival of patients with primary breast cancer. Determination of hormonal receptors, mainly progesterone’s, appear as the most powerful indicators. The analysis has generated a prognostic simplified classification, based in the 5 independent variables, that provides specific rates for survival at 2, 5 and 10 years.  相似文献   
58.
PURPOSE: Hypoxia is associated with adverse outcome for a number of solid tumors, including cervical carcinomas. Direct pO(2) measurement requires specialized equipment and expertise that is not generally available. Immunohistochemical measurement of intrinsic tissue markers of hypoxia is an alternative approach. Recent studies suggest that carbonic anhydrase IX (CA IX), which is regulated via hypoxia-inducible factor 1, is a useful intrinsic marker of tumor hypoxia. EXPERIMENTAL DESIGN: Biopsies were obtained from 110 patients with locally advanced cervical carcinoma treated with radiotherapy or chemoradiotherapy. Tissue sections were labeled using an immunofluorescence technique and CA IX expression in the viable tumor area measured using a semiautomated fluorescence image analysis technique. Results were compared with direct pO(2) values obtained using an Eppendorf probe and to patient outcome. Intratumoral heterogeneity of CA IX expression was examined in a subgroup of patient who underwent multiple biopsies. RESULTS: The median percentage of tumor area staining for CA IX was 3.56 (range, 0.01-58.85). CA IX staining did not correlate with the Eppendorf pO(2) measurements. Whereas the latter values were predictive of patient outcome, the CA IX levels were not. Measurement of CA IX in multiple biopsies indicated that intratumoral heterogeneity accounted for 41% of the total variance in the data set. CONCLUSIONS: In contrast to some recent studies, we did not find significant associations between CA IX expression and tumor pO(2) levels or patient outcome in locally advanced carcinomas of the cervix. Probable explanations relate to the problems of sampling error using single biopsies and the existence of biological factors other than hypoxia that influence CA IX levels.  相似文献   
59.
The authors report a case of thrombosis of the spermatic veins associated with Henoch-Sch?nlein purpura mimicking an acute scrotum, which responded to a low-molecular-weight heparin treatment.  相似文献   
60.
The metabolic syndrome among postmenopausal women in Ecuador.   总被引:1,自引:0,他引:1  
BACKGROUND: The prevalence of the metabolic syndrome increases with age and after the onset of menopause, and may explain in part the apparent acceleration of cardiovascular disease in postmenopausal women. OBJECTIVE: To determine the prevalence of metabolic syndrome and related risk determinants among postmenopausal women in Ecuador. METHODS: Postmenopausal women >or=40 years of age, non-users of hormone therapy and with an intact uterus, were asked to participate in a metabolic syndrome screening and educational program at the Institute of Biomedicine of the Universidad Católica of Guayaquil, Ecuador. Sociodemographic data, waist circumference and blood pressure measurements were recorded, and a fasting blood sample obtained for serum glucose and lipid profile determinations. Woman were counseled and managed according to the results. Metabolic syndrome was defined in accordance with the criteria of the Third Adult Treatment Panel (ATP III). RESULTS: Three hundred and twenty-five postmenopausal women entered the program. Mean (+/-standard deviation) age was 55.9 +/- 8.1 years, 53.5% of them were aged >or=54 years (median). The prevalence of metabolic syndrome, according to ATP III criteria, was 41.5%. Using the same criteria, 38.8%, 16.6%, 56.9% and 54.2% of the women presented with hypertension, diabetes, hypertriglyceridemia and abdominal obesity, respectively. More than 40% of women determined to have hypertension or diabetes lacked knowing so. Logistic regression analysis determined that age increased the risk of presenting hypertension and diabetes (odds ratio (95% confidence interval): 2.0 (1.2-3.2) and 1.6 (0.9-3.0), respectively, p < 0.05), entities which in turn duplicated the risk of having high triglyceride levels. Sedentary women with <5 years since menopause onset were at higher risk of having abdominal obesity, which was directly related to diabetes and hypertension. CONCLUSIONS: In this postmenopausal Ecuadorian population the prevalence of the metabolic syndrome was high and its determinant factors related to age, time since menopause onset and sedentary habits. Because of the implications for cardiovascular risk, counseling programs directed toward high-risk populations should be encouraged.  相似文献   
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