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201.
The goal of this research was to attempt to understand why white women are more prone to develop eating disorders than black women. Using self-reports, we found that white women chose a significantly thinner ideal body size than did black women, and expressed more concern than black women with weight and dieting. White women also experienced greater social pressure to be thin than did black women. White men indicated less desire than black men to date a women with a heavier than ideal body size, and white men felt they would more likely be ridiculed than did black men if they did date a woman who was larger than the ideal. The results suggest that black women experience eating disorders less than white women at least in part because they experience less pressure to be thin. 相似文献
202.
Reliable monitoring of electroencephalographic (EEG) and electromyographic electroconvulsive therapy (ECT) seizure duration has become important as these assessments have become a routine part of the clinical practice of ECT. In this regard, accurate automated seizure duration determinations would be particularly valuable. As a result, the present study was performed to assess the reliability of available computer-automated determinations of seizure duration (Thymatron Model DGx ECT machine; Somatics, Inc.) and to explore the factors upon which such reliability as well as the determinations of experienced raters depend. We found that the experienced human raters had very high interrater reliability, significantly higher than either did with the automated Thymatron DGx ratings. In general, the reliability of all ratings declined in the context of artifact, poor postictal suppression, or an EEG seizure end point that was reached gradually. Reliability was also greater for continuation ECT as compared with the index course. The reliability of Thymatron DGx versus experienced human ratings was particularly sensitive to these factors, ranging from 0.68 when several of these factors were simultaneously present to 0.999 when all these factors were absent. 相似文献
203.
The distribution of TmDOTP5- in rat tissue was compared with CoEDTA-, an anionic complex previously used as a marker of extracellular space. Heart, liver, muscle, blood, and urine were collected from rats after infusion of either complex and were quantitatively analyzed by atomic absorption spectroscopy. Although total TmDOTP5- in blood and tissue was consistently lower (0.88 +/- 0.04; n = 6) than CoEDTA- after an identical infusion protocol (presumably because of some association of the phosphonate complex with bone), a comparison of blood and tissue contents indicated that the two anionic complexes distributed into identical extracellular spaces. Relative extracellular space in the in vivo liver, as determined by TmDOTP5- and CoEDTA-, was 0.18 +/- 0.02 and 0.15 +/- 0.01, respectively. The corresponding relative extracellular space values for the in vivo heart reported by the two agents were identical (0. 11 +/- 0.02). Experiments were also performed to evaluate the washout kinetics of TmDOTP5- from anesthesized rats. In rats given a total dose of 0.16 mmol TmDOTP5-, 81% appeared in urine by 180 min, <2% was found in all remaining soft tissue, leaving approximately 18% undetected. The rate of Tm appearance in urine was fit to a standard pharmacokinetic model that included four tissue compartments: plasma, one fast equilbrating space, one slow equilibrating space, and one very slow equilibrating space (presumably bone). The best fit result suggests that the highly charged TmDOTP5- complex is cleared from plasma more rapidly than is the typical lower charged Gd-based contrast agents and that release from bone is slow compared with renal clearance. 相似文献
204.
R Kornowski GS Mintz AJ Lansky MK Hong KM Kent AD Pichard LF Satler JJ Popma TA Bucher MB Leon 《Canadian Metallurgical Quarterly》1998,81(11):1298-1304
This study assessed the impact of diabetes mellitus on atherosclerotic lesion formation. Seventy insulin-treated diabetics, 150 non-insulin-treated diabetics, and 607 nondiabetics with chronic anginal syndromes and de novo native coronary stenoses were studied using (1) angiography, and (2) intravascular ultrasound (reference and lesion arterial, lumen, and plaque areas; area stenosis [reference-lesion/reference lumen area]; remodeling index [reference-lesion lumen area/lesion-reference plaque area]; and slope of the regression line relating lumen area to plaque burden [plaque/arterial area]). Despite being diabetic for longer and having similar lumen compromise, insulin-treated patients had (1) less reference plaque (8.3 +/- 3.4 vs 10.5 +/- 4.5 mm2, p = 0.0015), (2) less stenosis plaque (13.0 +/- 4.9 vs 16.9 mm2, p <0.0001), (3) smaller reference arterial areas (17.1 +/- 5.4 vs 19.7 +/- 6.2 mm2, p = 0.0063), and (4) smaller stenosis arterial areas (15.3 +/- 4.9 vs 19.5 +/- 6.5 mm2, p <0.0001) than non-insulin-treated diabetics. With use of multivariate linear regression analysis, insulin use was an independent (and negative) predictor of reference plaque and arterial areas (p = 0.0308 and p = 0.0179) and stenosis plaque and arterial areas (p = 0.0117 and p = 0.0066). This was also true when normalized for body surface area. The remodeling index showed that insulin treatment resulted in an exaggerated impact of plaque accumulation on lumen compromise. This was confirmed by the slope of the regression line relating lumen area to plaque burden. Patients with a longer duration of diabetes who were treated with insulin for > or = 1 year had (paradoxically) less reference segment and stenosis plaque accumulation. Possible explanations include impaired adaptive remodeling and/or arterial (and plaque) shrinkage. 相似文献
205.
JR Petrie AD Morris CA Dorrian M Small JM Connell 《Canadian Metallurgical Quarterly》1997,90(7):465-475
Serum insulin concentrations have been used as markers of insulin resistance in population studies examining the relationship between insulin resistance and blood pressure, but the relationship is variable among studies. We hypothesized that differences in cross-reactivity of insulin assays with proinsulin and its split/des-amino products might account for the variation. We therefore examined fasting and post-glucose load serum insulin concentrations (determined by both specific and conventional assays), insulin sensitivity (measured by the euglycaemic clamp technique), and blood pressure, in a group of 56 diabetic (NIDDM) and non-diabetic subjects. Insulin concentrations as measured by the two methods were highly correlated (r = 0.97, p < 0.0001), and the relationships among serum insulin concentrations, insulin sensitivity and blood pressure were independent of assay method; for example, in non-diabetic subjects the univariate correlation between log10AUC insulin and insulin sensitivity index was similar with both methods [r = -0.81 vs. r = -0.82, p < 0.0001 (specific vs. conventional assay)]. Discrepancies between studies in the relationship between serum insulin concentrations and blood pressure are unlikely to be due to cross-reactivity of conventional insulin assays with proinsulin-like molecules. 相似文献
206.
RM Pitti SA Marsters DA Lawrence M Roy FC Kischkel P Dowd A Huang CJ Donahue SW Sherwood DT Baldwin PJ Godowski WI Wood AL Gurney KJ Hillan RL Cohen AD Goddard D Botstein A Ashkenazi 《Canadian Metallurgical Quarterly》1998,396(6712):699-703
Fas ligand (FasL) is produced by activated T cells and natural killer cells and it induces apoptosis (programmed cell death) in target cells through the death receptor Fas/Apol/CD95. One important role of FasL and Fas is to mediate immune-cytotoxic killing of cells that are potentially harmful to the organism, such as virus-infected or tumour cells. Here we report the discovery of a soluble decoy receptor, termed decoy receptor 3 (DcR3), that binds to FasL and inhibits FasL-induced apoptosis. The DcR3 gene was amplified in about half of 35 primary lung and colon tumours studied, and DcR3 messenger RNA was expressed in malignant tissue. Thus, certain tumours may escape FasL-dependent immune-cytotoxic attack by expressing a decoy receptor that blocks FasL. 相似文献
207.
To elucidate the role of autoantibodies and ultraviolet (UV) exposure in the pathogenesis of the skin lesions in neonatal lupus erythematosus (NLE), keratinocytes were cultured, as the target cells, from a patient with NLE and from a normal neonate. We demonstrated that the expression of nuclear/cytoplasmic Ro/SSA and La/SSB molecules on to the surface of NLE keratinocytes occurred to a much greater extent than that on normal keratinocytes. A dose of 200 mJ/cm2 UVB irradiation on NLE keratinocytes induced a 2.5-3-fold increase in Ro/SSA and La/SSB expression compared to non-irradiated cells. Sera derived from both the NLE patient and from his mother exhibited a cytotoxic effect on NLE keratinocytes, but not on control cells, in the presence of complement. Furthermore, the cytotoxicity of the sera was enhanced on UVB-irradiated NLE keratinocytes, whereas it had no cytotoxic effects on UVB-irradiated control cells. This suggests that the abnormal expression of both Ro/SSA and La/SSB on the surface membrane of NLE keratinocytes induces the autoantibodies and complements to injure the cells. This complement-mediated cytotoxic effect can be augmented by UV irradiation, a concept not incompatible with the exacerbation of the skin eruption in sun-exposed skin sites. 相似文献
208.
AD Anichkov AV Vodianov SV Mozhaev TN Trofimova VB Nizkovolos AV Obliapin IuZ Polonski? AL Spirin 《Canadian Metallurgical Quarterly》1998,(3):6-9; discussion 9-10
The paper summarizes experience with stereotactic operations by magnetic resonance imaging data by using a Russian OREOL stereotactic manipulator. It describes methods of preoperative preparation of patients by employing diagnostic magnetic resonance tomographs. A number of points of the procedure for identification and localization of deep target structures from magnetic resonance images in parkinsonism, temporal epilepsy and some mental disorders. 相似文献
209.
SF Shakar WT Abraham EM Gilbert AD Robertson BD Lowes LS Zisman DA Ferguson MR Bristow 《Canadian Metallurgical Quarterly》1998,31(6):1336-1340
OBJECTIVES: We sought to assess the effects of combined oral positive inotropic and beta-blocker therapy in patients with severe heart failure. BACKGROUND: Patients with severe, class IV heart failure who receive standard medical therapy exhibit a 1-year mortality rate >50%. Moreover, such patients generally do not tolerate beta-blockade, a promising new therapy for chronic heart failure. Positive inotropes, including phosphodiesterase inhibitors, are associated with increased mortality when administered over the long term in these patients. The addition of a beta-blocker to positive inotropic therapy might attenuate this adverse effect, although long-term oral inotropic therapy might serve as a bridge to beta-blockade. METHODS: Thirty patients with severe heart failure (left ventricular ejection fraction [LVEF] 17.2+/-1.2%, cardiac index 1.6+/-0.1 liter/min per m2) were treated with the combination of oral enoximone (a phosphodiesterase inhibitor) and oral metoprolol at two institutions. Enoximone was given at a dose of < or = 1 mg/kg body weight three times a day. After clinical stabilization, metoprolol was initiated at 6.25 mg twice a day and slowly titrated up to a target dose of 100 to 200 mg/day. RESULTS: Ninety-six percent of the patients tolerated enoximone, whereas 80% tolerated the addition of metoprolol. The mean duration of combination therapy was 9.4+/-1.8 months. The mean length of follow-up was 20.9+/-3.9 months. Of the 23 patients receiving the combination therapy, 48% were weaned off enoximone over the long term. The LVEF increased significantly, from 17.7+/-1.6% to 27.6+/-3.4% (p=0.01), whereas the New York Heart Association functional class improved from 4+/-0 to 2.8+/-0.1 (p=0.0001). The number of hospital admissions tended to decrease during therapy (p=0.06). The estimated probability of survival at 1 year was 81+/-9%. Heart transplantation was performed successfully in nine patients (30%). CONCLUSIONS: Combination therapy with a positive inotrope and a beta-blocker appears to be useful in the treatment of severe, class IV heart failure. It may be used as a palliative measure when transplantation is not an option or as a bridge to heart transplantation. Further study of this form of combined therapy is warranted. 相似文献
210.
OBJECTIVE: To investigate the dysregulation of cytokeratin 20 (CK20) expression in urothelial dysplasia and its potential as a diagnostic aid. PATIENTS AND METHODS: Twenty-two patients were selected on the basis that they had undergone one or more biopsies showing dysplasia before the development of a transitional cell carcinoma (TCC): 15 of these patients also had a prior history of TCC. The dysplasia was classified as mild in 12, moderate in 14 or severe dysplasia/carcinoma in situ in 10 patients, ensuring that a spectrum of morphological appearances was represented. Control biopsies were obtained from seven children undergoing bladder reconstructions and 23 patients with recurrent urinary tract infections, haematuria or functional bladder symptoms, but no history of TCC. RESULTS: The expression of CK20 was restricted to superficial 'umbrella' cells and occasional intermediate cells in the control biopsies, even in the presence of severe inflammation. In 31 of the 36 cases of dysplasia complete loss of restriction was seen at least focally with positive expression in all layers of the urothelium. CONCLUSION: The abnormal expression of CK20 is a reliable, positive marker of urothelial dysplasia in the urinary bladder. Immunostaining for CK20 is therefore a useful adjunct to morphology in the diagnosis of dysplasia, of particular value in the distinction from reactive states where diagnostic difficulties are greatest. 相似文献