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51.
Endothelin receptors (ETRs) display subtype heterogeneity and are widely distributed throughout the tissues of the periphery and central nervous system. In order to gain further insight into the potential molecular differences of ETRs, we initiated molecular cloning of ETR genes by screening for the appearance of 125I-ET-1 binding activity in COS cells transfected with pools of a porcine cerebellum cDNA expression library. Two independent clones (pPCETR 1.1 and pPCETR 5.6) were identified and isolated by repeated rounds of pool enrichment and COS cell expression. DNA sequence analysis of pPCET 1.1 and pPCET 5.6 indicated that both clones have the same nucleotide sequence; the deduced amino acid sequence indicated that the porcine cerebellum ETR is 443 residues in length and consists of seven potential transmembrane domains, with homology to members of the GTP-binding protein-coupled receptor superfamily. Northern analysis indicated a single mRNA species of about 5 kilobases, which is expressed significantly in cerebellum, lung, kidney, and pituitary. Expression of functional receptor was demonstrated by endothelin-1 (ET-1)-mediated Ca2+ mobilization in COS cells transfected with pPCETR 1.1 (COS/ETR 1.1) and ET-1-mediated electrophysiological responses in Xenopus oocytes injected with RNA derived from pPCETR 1.1. Quantitative comparison of saturation binding of 125I-ET-1 to either porcine cerebellum or COS/ETR 1.1 membranes indicated an identical apparent dissociation constant. The relative efficacy of ET-related peptides to compete for binding of 125I-ET-1 to receptor from porcine cerebellum and COS/ETR 1.1 indicated that both preparations encode a nonselective or ETBR subtype. Chemical cross-linking of 125I-ET-1 to receptor derived from cerebellum or COS/ETR 1 revealed two bands, with apparent molecular masses of 47 and 35 kDa. These data demonstrate that the pPCETR 1.1 encodes the major ETR subtype in the porcine cerebellum.  相似文献   
52.
In the present work we report our studies on IgG separated from the serum of lepromatous patients and non-lepromatous leprosy cases using Laser Raman Spectroscopy. Striking spectral changes in LL cases have been observed in the following special regions: (a) the amide I and III, (b) the S-S and C-S stretching (c) the skeletal bending and (d) skeletal stretching regions. These changes indicate a decrease in the amount of beta-structure and a transition towards alpha-helical conformation.  相似文献   
53.
The alterations in the oesophageal epithelium were studied in mice after a single whole-body exposure to 7.5 Gy of Co-60 gamma rays in presence or absence of 2-mercaptopropionyl glycine. The epithelium showed an increase in the thickness which reached a maximum on the third day and then decreased gradually up to seventh day after irradiation in the non-drug treated group. In the 2-mercaptopropionyl glycine treated animals the epithelial thickness remained in the normal range except on the day 7 when it was significantly lower than normal. The total cell population registered a steady decline from one to seven days post-irradiation in both groups, but the number of cells was more in the 2-mercaptopropionyl glycine treated group. The number of pycnotic nuclei showed an inverse relationship to the total cell population, it increased continuously up to seven days in both the protected and non-protected groups. However, pycnotic nuclei were significantly lower in the protected group on days 3, 5 and 7 in non-protected group.  相似文献   
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Diagnosis of dementia needs to be complemented by precise determination of disease severity across the broad spectrum of disease progression. The Mini-Mental State Exam (MMS), the Activities-of-Daily-Living assessment (ADL) and the Clinical Dementia Rating scale (CDR) were modified for direct comparability and administered to 112 outpatients and 45 nursing home residents with a range of dementia severity from mild to profound. The scales showed the highest correlations for the probable Alzheimer's disease patient group (62) (Global Assessment of Dementia; GAD vs. ADL: r = 0.91; Extended Mini-Mental Assessment; EMA vs. GAD: r = 0.91; ADL vs. EMA: r = 0.86). For these patients, scores on the individual scales tended to be similar. Disparity among the three scores for individual cases was associated with the presence of comorbidities. The high correlations and correspondence among these scales demonstrate their reliability, validity, and utility in the assessment of dementia severity. The use of an average of these measures, with their increased precision, may give a more accurate indication of dementia severity over a broader range of impairment.  相似文献   
56.
Intracellular sodium in proximal tubules of diabetic rats. Role of glucose   总被引:1,自引:0,他引:1  
Renal hypertrophy is a common consequence of diabetes mellitus that precedes and possibly accounts for the increased glomerular filtration rate. We have postulated that the glucose-mediated increase in the intracellular concentration of sodium [Na]i initiates the chain of events leading to the increase in cell size and eventually cell number. Experiments were conducted on Sprague-Dawley rats made diabetic by the intravenous injection of 45 mg/kg body wt of streptozotocin dissolved in a 5 mM citrate buffer solution. Control animals were injected with the vehicle alone. Ninety-six hours and 11 weeks later, measurements of [Na]i were done by NMR spectroscopy on suspensions of proximal tubules, using dysprosium tripolyphosphate as an extracellular shift reagent. At 96 hours after the induction of the diabetes, there was a 60% increase in [Na]i compared to control (P less than 0.01). No further increase in [Na]i was observed during the subsequent 11 weeks of observation. Addition of ouabain (1.0 mM) resulted in a fourfold increase in [Na]i in tubules from control animals, and a 2.5-fold increase in tubules from 96-hour diabetic rats. Ouabain-inhibitable Na+-K+-ATPase activity was substantially higher in the renal tubules of diabetic rats, the increase being proportional to that of [Na]i. In order to ascertain the effect of hyperglycemia on [Na]i, proximal tubules prepared from kidneys of normal and diabetic rats were exposed to low (5 mM) and high (25 mM) concentration of glucose in the media.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
57.
Food systems are complex and inhomogeneous in nature. Ultrasonic propagation velocity in the food systems, in this case processed milk cream and vegetable oils, is studied. Ultrasonic properties of the food systems are similar to those of complex biological tissues. The presence of vegetable oil as an adulterant in the processed milk cream is detected with the help of a double-probe-through-transmission ultrasonic technique. The present study helps to maintain quality control of various food systems, particularly with regard to their adulteration, if any.  相似文献   
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Two children out of three siblings of a family presented with tiredness, fatigue, and breathlessness for more than 6 months. Examination of peripheral blood smear, bone marrow aspirate, and a positive acidified serum test (HEMPAS) revealed these children to be a case of congenital dyserythropoietic anemia type II. This case is reported because of its rarity.  相似文献   
60.
Editorial     
Evidence-Based Integrative Medicine -  相似文献   
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