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21.
Empty Sella and Headache   总被引:2,自引:0,他引:2  
SYNOPSIS
Empty sella is an anatomical condition caused by herniation of the subarachnoid space into the pituitary fossa through an incompetent seller diaphragm. Headache seems to be one of the most frequently reported symptoms. We studied 13 headache patients (12 females, 1 male) presenting with primary empty sella (PES) on CT scan. The characteristics of the headache were analyzed and plasma levels of pituitary hormones or cortisol assessed. We confirmed the nonspecific nature of the headache in PES even though the majority of our patients complained of daily headache, mostly localized anteriorly. Hormone plasma levels were within normal range in all the patients assessed. However, four patients reported earlier endocrine disorders and more than half of the patients presented with obesity.
In our opinion, PES should be suspected in middle-aged overweight women with daily headache even in the absence of endocrine symptomatology.  相似文献   
22.
This study was performed to examine the pattern of Superoxide (O 2 ·) generation from leukocytes using the O 2 · specific chemiluminescence (CL) method.Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA) was used as a CL probe. The appropriate conditions of the MCLA method was first determined for the evaluation of the time course of O 2 · generation by leukocytes. The time course of O 2 · generation obtained by the MCLA-CL system was compared with that by the luminol-dependent CL, electron spin resonance (ESR)/spin trapping, and cytochromec systems. Following stimulation by three different stimulants (PMA, OZ, FMLP), leukocytes continuously generated O 2 · for up to 5 h in the MCLA-CL system, irrespective of the kind of stimulation. The curves obtained by generation ceased more rapidly in the luminol-CL, ESR/spin trapping, and cytochromec systems. A 50% activity of the initial value was observed at 70 min in the MCLA-CL system, but 30, 10 and 35 min in the other systems, respectively. The CL or O 2 · generation value decreased to less than 1% (possible termination) at 300, 90, 120 and 180 min, respectively. With the exception of ESR studies with OZ, the cell viability was not significantly affected in any of the trials. These results indicate that leukocytes can generate O 2 · much longer than previously estimated and that the MCLA-CL-system is the most suitable system for the measurement of the O 2 · generation by leukocytes.  相似文献   
23.
We prospectively investigated whether alcohol intake and smoking affect the risk of basal cell carcinoma (BCC) in subjects from the United States Radiological Technologists (USRT) cohort study. We evaluated 68,371 radiological technologists certified during 1926-1982 who were free of cancer at the time they answered a first questionnaire (1983-1989) and who completed a second questionnaire (1994-1998). The first questionnaire provided baseline information on numerous risk factors, including smoking and alcohol intake, and the second provided self-reported cancer diagnoses. During 698,190 person-years of follow-up, we identified 1,360 cases of BCC: 1,036 in women and 324 in men. Cox proportional hazards regression indicated that the trend in BCC was significantly associated with increased alcohol intake (P for trend = 0.001). Compared with those who reported no alcohol consumption, those who drank <1-2, 3-6, 7-14, and >14 drinks/week had multivariate risks of 1.1 [95% confidence interval (CI), 0.9-1.3], 1.3 (95% CI, 1.1-1.5), 1.4 (95% CI, 1.2-1.7), and 1.0 (95% CI, 0.7-1.6), respectively. We found no clear association between smoking and BCC. This is the second large prospective study to report a significant but nonmonotonic trend in increased risk associated with alcohol consumption.  相似文献   
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This paper describes the implementation of a community-based youth violence prevention project that utilized an educational curriculum and a mass media campaign. The extent of penetration of the intervention into target areas and the degree of contamination of control areas are assessed, and the most frequently contacted forms of educational outreach are identified. Two sources of data, provider interviews and a random digit dialed telephone survey, were used to track the source and extent of teens' exposure to the intervention. Agency provider data revealed that 40% of the 92 contacted agencies actually conducted violence prevention education, reaching 22% of the target area teens. Approximately one-half of the surveyed teens reported some exposure to the program, with 13% of the teens in target areas reporting participation in interactive educational activities associated with the project. The most common source of exposure was the media campaign. Most teens report a single exposure, usually to the media campaign, although 29% report contact with more than one form of violence prevention education. While the project did not achieve community saturation, the data show that the community-based model of intervention for violence prevention is feasible and effective in reaching teenagers. This research highlights some difficulties in evaluating prevention programs, including reconciling community ownership with project identification, the ethics of curtailing services for control purposes, and factors influencing recall of participation.  相似文献   
27.
The cortisol stress response to capture was investigated in two species of fish (Perca flavescens and Esox lucius) from sites polluted by high levels of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and mercury, and from reference sites in the St. Lawrence river system. Fish from the reference sites exhibited the normal elevation of serum cortisol in response to the acute stress of capture and had large pituitary corticotropes. In contrast, fish from the most polluted sites were unable to increase their serum cortisol in response to the acute stress of capture and their pituitary corticotropes were atrophied. These results suggest that a life-long exposure to chemical pollutants may lead to an exhaustion of the cortisol-producing endocrine system, possibly as a result of prolonged hyperactivity of the system.  相似文献   
28.
ABSTRACT: This paper reports on the effectiveness of a teacher development project in promoting implementation of a comprehensive school health education curriculum among inner city elementary school teachers. The longitudinal evaluation design provides empirical data on the efficacy of a strategy to reduce teachers' concerns and promote use of the curriculum at the classroom level. Data were collected at various points throughout the project period from 156 school staff from five schools. Results from analyses of repeated measures of teachers' feelings of preparedness to teach specific health topics, and the observed relationship between both high and improved feelings of preparation and reported health teaching suggest that teacher development efforts including training and ongoing reinforcement to increase teachers' feelings of preparedness can have significant classroom effects.  相似文献   
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To characterize apoptosis in keloids and the mechanisms responsible for this process, the expression of activated caspase-9 and -3 in fibroblasts obtained from keloids was analyzed. Immunohistochemistry revealed that the number of fibroblasts positive for terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) or activated caspase-9 or -3 was low but was significantly higher in keloid tissues than in normal scar tissues. Significant relationships between the number of caspase-positive fibroblasts and TUNEL-positive fibroblasts suggested that the activation of caspase-9 and -3 induces apoptosis in a subpopulation of keloid fibroblasts. All keloid fibroblast cell lines established in this study showed activation of caspase-9 and -3 after serum deprivation for 3 or 4 hours, as shown using Western blotting. Furthermore, serum deprivation-induced apoptosis in a keloid fibroblast line was blocked by a caspase-9 inhibitor (acetyl-Leu-Glu-His-Asp-al), indicating that activation of caspase-9 was necessary for the process of apoptosis in keloid fibroblasts. Although serum deprivation did not significantly change the level of apoptosis protease activating factor-1 in any of the lines, cytochrome c release was detected in cytosolic fractions of the lines after serum deprivation for 3 or 4 hours. These results strongly suggest that keloid fibroblasts are predisposed to apoptosis and cytochrome c release and that caspase-9 activation may underlie regulation of apoptosis in keloid fibroblasts in vivo.  相似文献   
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