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111.
Data on height, weight, illness, medical care consumption, and demographic variables for 19,126 Dutch adults aged 20 years or older were obtained from three annual Health Interview Surveys. Data on severely overweight (Body Mass Index 30.0-40.0 kg/m2) and moderately overweight (BMI 25.0-29.9 kg/m2) subjects were compared with those on non-overweight persons (BMI 20.0-24.9 kg/m2), taking into account effects of sex, age, and educational level. In men, severe overweight was associated with hypertension, especially in men under 50 years of age. In women, severe overweight was associated with hypertension, diabetes, varicose veins, asthma/bronchitis, and hemorrhoids. Increased utilization of medical care and medications were also associated with severe overweight. For moderately overweight subjects, these associations were less clear or absent.  相似文献   
112.
To evaluate the use of three-dimensional (3D) echocardiography in the diagnosis of congenital heart defects, we studied 238 patients aged 3 days to 19 years (mean 4.3 years) with normal hearts ( n = 13) or a variety of congenital heart defects (n = 225) Three different modalities of data acquisition suitable for reconstruction were applied For parallel scanning, the transducer is held in a 6-cm long scan frame and then moved over the thorax, or in the subcostal position, by a stepper motor using 0.5-mm steps with acquisition of perpendicular parallel images of the heart For rotational scanning, the transducer is rotated at sectors of 2° over a span of 180° For fan-like scanning, the transducer is moved in an arc 45° each way from its vertical axis Movement of the transducer is computer-controlled and performed with electrocardiography and respiratory gating Between 80 and 120 slices of the heart are thus obtained, which form the dataset This dataset can then be "sectioned" in any desired plane, thus permitting generation of views simulating intraoperative perspectives Ventricular septal defects and atrioventricular valves can be displayed as viewed via the atrium Muscular ventricular septal defects can be viewed as seen through a ventriculotomy Obstruction in the left ventricular outflow tract can be viewed as via an aortotomy, and so on We conclude that this new imaging modality has a vast potential and may facilitate planning of intracranial surgery.  相似文献   
113.
The ability to distinguish between intra-abdominal and subcutaneous abdominal fat may be important in epidemiologic and clinical research. In this study anthropometric measurements were taken from 71 men and 34 women presenting for routine computed tomography (CT). Areas of abdominal fat were calculated from CT scans made at the level of the L4 vertebra. The amounts of intra-abdominal and subcutaneous abdominal fat could be accurately predicted from several circumferences, skinfold measurements, body mass index, and age (R2 ranged from 0.79 to 0.84). In addition, it was found that the area of intra-abdominal fat on the CT scan was related to the waist:hip circumference ratio (r = 0.75 in men, r = 0.55 in women) and to the waist:thigh circumference ratio (r = 0.55 in men, r = 0.70 in women). The correlations of the circumference ratios with the areas of subcutaneous fat were invariably lower.  相似文献   
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Induction of microgyria by freezing injury to the developing somatosensory cortex of neonatal rats causes a defect in fast auditory processing in males, but not in females. It was speculated that early damage to the cortex has sexually dimorphic cascading effects on other brain regions mediating auditory processing, which can lead to the observed behavioral deficits. In the current series of experiments, bilateral microgyri were induced by placement of a freezing probe on the skulls of newborn male and female rats, and these animals were tested in adulthood for auditory temporal processing. Control animals received sham surgery. The brains from these animals were embedded in celloidin, cut in the coronal plane and the following morphometric measures assessed: microgyric volume, medial geniculate nucleus (MGN) volume, cell number, and cell size, and, as a control, dorsal lateral geniculate nucleus (dLGN) volume, cell number and cell size. There were no sex differences in the cortical pathology of lesioned animals. However, microgyric males had more small and fewer large neurons in the MGN than their sham-operated counterparts, whereas there was no difference between lesioned and sham-operated females. There was no effect on dLGN cell size distribution in either sex. Microgyric males were significantly impaired in fast auditory temporal processing when compared to control males, whereas lesioned females exhibited no behavioral deficits. These results suggest that early injury to the cerebral cortex may have different effects on specific thalamic nuclei in males and females, with corresponding differences in behavioral effects.   相似文献   
117.
Cheng  TY; Wu  JT; Lin  RH 《International immunology》1998,10(10):1397-1406
Sufficient CD4+ T cell help is very important in generating specific cytotoxic T cell responses. The inadequate activation of tumor-specific Th cells leads to failure of antitumor immunity. In general, each individual consists of some primed Th cells responding to certain antigens. If these tumor non-specific pre-primed Th cells can provide sufficient help, the generation of tumor-specific T cells may be enhanced. In the present study, we tested this hypothesis by cognating and reactivating pre-primed ovalbumin (OVA)-specific Th cells with OVA- pulsed tumor cells which could simultaneously present both OVA and tumor-associated antigen on the same cell. We clearly demonstrated that immunization of OVA-sensitized mice with OVA-pulsed P388 cells, but not unpulsed P388 cells, led to the induction of P388-specific cytotoxicity and tumor resistance. Both CD4+ and CD8+ tumor-specific cytotoxic T cells were detected in vitro, but only CD8+ T cells played the major effector role in preventing the growth of challenged tumor in vivo. Taken together, our study demonstrated that the immunogenicity of tumor cells can be enhanced effectively by cognating pre-primed foreign antigen-specific Th cells with tumor cells. These findings have potential implications in developing methods to control tumor growth.   相似文献   
118.
Fifteen premenopausal obese women, seven abdominal obese (AO) and eight gluteal-femoral obese (GFO), followed an energy-reduced diet of 1000 kcal/d (4.2 MJ/d) over 8 wk. Body-fat distribution was assessed using a cutoff point of 0.80 for the waist-to-hips girth ratio. Before and after the dietary treatment resting metabolic rate (RMR) and diet-induced thermogenesis (DIT) (after a normal breakfast) were measured by indirect calorimetry. Body-weight reduction and energy intake during the diet period did not differ significantly between both groups. Before weight loss the AO group had slightly greater RMR than the GFO group. After weight loss mean RMR decreased about 10% in the AO group and about 2.5% in the GFO group. Before weight loss DIT was slightly but not significantly higher in the AO group than in the GFO group. After weight loss DIT increased significantly in the GFO group. Weight loss was generally associated with decreased blood glucose, serum triglycerides, and total serum cholesterol levels in the AO women but not in the GFO women.  相似文献   
119.
Techniques have been developed for isolated perfusion of chemotherapeutic agents in patients with glioblastoma. Three catheters that facilitate crossing the carotid siphon have been developed; two are based on an everting or toposcopic principle, and one uses microjets for deflectability and improved mixing. Blood from the ipsilateral jugular vein is aspirated at high volumes (300 ml/min) for extracorporeal circulation through an adsorption column (for recovery of carmustine) or dialysers (for recovery of cisplatin). Preliminary experience in 10 patients suggests that high doses of chemotherapeutic agent can be administered using these catheters, with reduced retinal and systemic toxicity.  相似文献   
120.
Fourteen patients and five healthy individuals underwent magnetic resonance (MR) imaging to determine an effective multiple spin echo pulse sequence for estimating T2. Lesions examined included infarction, glioma, multiple sclerosis, and acute hematoma. A pulse repetition time (TR) of 1,500 msec and echo delays (TEs) of 25, 50, 75, and 100 msec were used. Computed T2 images were derived from all four echoes, the first two echoes, and the first and fourth echoes. T2 values were obtained from specific brain locales using region-of-interest analysis. Use of either the first two echoes or the first and fourth in the T2 fit provided T2 estimates which closely correlated with that of the four-echo analysis. The noise level in T2 maps constructed from the 25- and 100-msec echoes was modestly (typically 10%) higher than that from four echoes; noise level from the 25- and 50-msec echoes was markedly higher, typically 60%. This behavior is remarkably consistent with that predicted from theory. All 19 subjects displayed consistent relative T2 values for specific brain structures; in 13, the absolute T2 values fell within a limited range. Despite the high sensitivity of T2 images, their specificity in the detection of most brain disease appears limited except in acute intracerebral hematoma, which exhibited a decreased T2 relaxation time using high-field-strength MR imaging.  相似文献   
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