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91.
C Clayton M Adams R Almeida T Baltz M Barrett P Bastien S Belli S Beverley N Biteau J Blackwell C Blaineau M Boshart F Bringaud G Cross A Cruz W Degrave J Donelson N El-Sayed G Fu K Ersfeld W Gibson K Gull A Ivens J Kelly L Vanhamme 《Canadian Metallurgical Quarterly》1998,97(1-2):221-224
We investigated the effect of chronic ethanol administration and its withdrawal on the polypeptide levels of NMDA receptor subunits such as NR1, NR2A, and NR2B in the rat cerebral cortex and hippocampus using Western blot analysis technique. Our results indicate that chronic ethanol treatment upregulates NMDA receptor subunits NR1, NR2A, and NR2B ( approximately 35%). At 48 h of last dose of ethanol administration, the protein content returned to almost control level, thereby demonstrating the reversibility of the changes. 相似文献
92.
WA Briggs ZH Gao JJ Xing PJ Scheel LF Gimenez MJ Choi JF Burdick 《Canadian Metallurgical Quarterly》1996,8(10):804-808
IFN-gamma is a potent pro-inflammatory cytokine involved in the immunologic rejection of transplanted organs. Having previously demonstrated differential suppressive effects of methylprednisolone (MP), prednisolone (P) and cyclosporine (CsA) on dialysis patients' lymphocyte proliferative responses to phytohaemagglutinin (PHA), we studied the effects of these drugs on dialysis patients' lymphocyte IFN-gamma production during mitogenic and allogeneic (MLR) stimulation. The mean +/- SEM 50% inhibitory concentration (ng/ml) on cell proliferation was significantly lower for MP than P in PHA-stimulated haemodialysis (HD) patients' (35 +/- 7 vs 152 +/- 25, P < 0.001) and peritoneal dialysis (PD) patients' (35 +/- 11 vs 134 +/- 33, P = 0.001) cultures and in HD patients' MLR cultures (15 +/- 3 vs 48 +/- 9, P < 0.001). The mean +/- SEM fractional responses (PHA or MLR + drug/PHA or MLR) in culture supernatant IFN-gamma concentrations were significantly lower with 10(-7) M concentrations of MP than P in HD (0.19 +/- 0.05 vs 0.31 +/- 0.06, P = 0.01) and PD (0.30 +/- 0.11 vs 0.46 +/- 0.11, P < 0.05) PHA cultures and in HD MLR cultures (0.15 +/- 0.04 vs 0.28 +/- 0.07, P = 0.01). CsA (400 ng/ml) alone not only caused less than 50% inhibition of IFN-gamma production in 15/27 HD PHA, 6/14 PD PHA and 4/13 HD MLR cultures, but actually stimulated it in 9 HD and 5 PD PHA cultures. The results suggest that: (1) MP has greater immunosuppressive potential than P for renal transplant recipients; (2) the stimulation of IFN-gamma by CsA in some patients could be harmful in patients with initial allograft dysfunction; and (3) pre-transplant in-vitro assessment of recipients' PBMC responsiveness to glucocorticoids and CsA may help individualize the post-transplant immunosuppressive regimen. 相似文献
93.
94.
LF Pascual-Millán 《Canadian Metallurgical Quarterly》1998,26(152):582-584
OBJECTIVE: To review the relationship between quality of life (QOL) and dementia. Development. QOL is a factor which takes into account all the different aspects of life which make a person feel that life is worth living, such as: 1. Physical health. 2. Functional status. 3. Psychological and cognitive sphere, and 4. Social health. There are two types of instruments for evaluating these aspects: firstly general ones which measure the QOL independently of illness, and secondly those which are specific to the illness concerned. In dementia, QOL covers the same traditional areas: cognitive competence, capacity to carry out everyday activities, social conduct and the balance between positive and negative emotions. However, evaluation of QOL in dementia has its own specific difficulties, since it is often impossible to determine such a fundamental factor as the subjective well-being of the patient, in which case the opinion of the person looking after the patient is essential. According to Lawton's approximation, as well as the subjective aspect of perceived psychic welfare and quality of life, the QOL in dementia is composed of external social and objective dimensions such as behaviorally competence and the quality of the patient's environment. In a review done in 1995 it was found that most of the instruments designed to measure the QOL have not been sufficiently validated for Alzheimer's disease. CONCLUSIONS: QOL in dementia has specific features including external aspects such as the opinion of the carer and the quality of the patient's environment in addition to the subjective aspects. It is necessary to develop and validate specific instruments for QOL in dementia. 相似文献
95.
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
96.
PE Alonso E Bescansa J Salas J de Haro A Redondo LF Rioja 《Canadian Metallurgical Quarterly》1995,48(8):564-568
This paper reports two cases of orbital apex syndrome. The most salient clinical signs, ophthalmoplegia and eyelid ptosis, arose from perineural spread of facial squamous cell carcinomas that were previously excised with tumour-free surgical margins and exhibited no signs of local or other regional recurrence. The interest of these two cases lies in the fairly rare occurrence of this type of tumour spread and the highly aggressive nature of the tumour, unequivocal diagnosis of which usually arrives too late for a surgical solution. Awareness of the possibility of such perineural spread may allow the clinician to establish an early diagnosis and thus undertake radical surgery, thereby increasing the likelihood of success in combination with postoperative radiotherapy. 相似文献
97.
LF Kubena TS Edrington C Kamps-Holtzapple RB Harvey MH Elissalde GE Rottinghaus 《Canadian Metallurgical Quarterly》1995,74(2):306-313
Diets containing 300 mg fumonisin B1 (FB1)/kg of feed and 5 mg T-2 toxin/kg of feed singly or in combination were fed to female turkey poults (Nicholas Large White) from day of hatch to 21 d of age. When compared with controls, 21-d body weight gains were reduced 21% by FB1, 26% by T-2, and 47% by the combination. the efficiency of feed utilization was adversely affected by FB1 and the combination of FB1 and T-2. Relative weights (grams/100 g BW) of the liver and gizzard were increased in poults fed the FB1 and the combination diets; whereas, the relative weight of the pancreas was increased in all treated groups. All poults were scored for oral lesions using a scale of 1 to 4 (1 = no visible lesions, 4 = severe lesions). Oral lesions were present in all poults fed the T-2 diet (average score of 3.29) or the combination diet (average score of 3.54). Serum concentration of cholesterol was decreased and lactate dehydrogenase activity was increased in poults fed the FB1 and combination diets. The activity of aspartate aminotransferase and the values for red blood cells, hemoglobin, and hematocrit were increased only in poults fed the combination diet. Inorganic phosphorus concentration was decreased only in poults fed the combination diet. The increased toxicity in poults fed the combination diet for most variables can best be described as additive, although some variables not altered by FB1 or T-2 singly were significantly affected by the combination, indicating that the combination may pose a potentially greater problem to the turkey industry than either of the mycotoxins individually. 相似文献
98.
In the past, biomechanical investigations on the dorsal pelvic ring have generally been performed on a small number of cadaveric pelves in various non-standardized procedures. Significant differences in stability between different internal fixation methods of unstable pelvic ring fractures were not found. The experimental design presented here was based as closely as possible on the physiological loading of the pelvis in one-leg stance. This method made it possible to carry out standardized, reproducible tests on different osteosytheses of the sacroiliac joint. Furthermore, the suitability of artificial bones for such investigations can be assessed on the basis of a larger number of similar experiments on artificial and human pelves and the number of human pelves required for such studies could be reduced. 相似文献
99.
Y. Soong A. G. Blackwell R. R. Schehl M. F. Zarochak J. A. Rayne 《Chemical Engineering Communications》1995,138(1):213-224
An ultrasonic technique is under development for measuring solids concentration in a three-phase slurry reactor. Preliminary measurements have been made on slurries consisting of water, glass beads, and air bubbles. The data show that both the sound speed and attenuation are well-defined functions of both the solid and gas concentrations in the slurries. A simple model is proposed to correlate the solids concentration with the measured ultrasonic signals. 相似文献
100.