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1.
BACKGROUND: Measurement of muscle mass is useful for evaluating protein nutritional status. Various methods for estimating muscle mass in haemodialysis patients have recently been developed. METHODS: The validity of the estimate of creatinine production calculated with the creatinine kinetic model (CKM) was examined in 46 haemodialysis patients by comparing it with the actual creatinine production, this being determined from the sum of creatinine appearing in the dialysate and the estimated metabolic degradation. The correlation of various other muscle mass indices with creatinine production was also investigated in these patients. RESULTS: The estimate of creatinine production using CKM was significantly correlated with creatinine production calculated from the spent dialysate plus an estimate for the extra-renal creatinine degradation (r=0.90, P<0.001). A Bland-Altman analysis revealed that the mean prediction error for the estimate of creatinine production by CKM was +0.10 g/day and the limits of agreement were +0.34 to -0.14 g/day. The cross-sectional area of the thigh muscle measured by computed tomography (CT) was also significantly correlated with creatinine production (r=-0.86, P<0.01). In contrast, the correlations of 3-methylhistidine production measured in the spent dialysate, the mid-upper arm muscle circumference and the skeletal muscle mass estimated by an anthropometric prediction model with creatinine production were lower (r<0.82). CONCLUSION: Creatinine production calculated using CKM and CT measurement of thigh muscle area are valid methods for estimating muscle mass during routine clinical examinations of haemodialysis patients.  相似文献   
2.
AIM: To investigate the participation of adenosine receptors in the adenosine 5'-triphosphate (ATP)-induced relaxation in the corpus cavernosum penis (CCP) of rabbits. METHODS: The ATP-induced relaxation was assessed on the noradrenaline precontracted CCP of rabbits in the presence and absence of 8-(3-chlorostyryl)caffeine (CSC); an adenosine A(2A) receptor antagonist; alloxazine and MRS1754; adenosine A(2B) receptor antagonists; and ARL67156, an inhibitor of ecto-nucleoside triphosphate diphosphohydrolases. RESULTS: Adenosine and ATP relaxed the noradrenaline precontracted CCP of rabbits in a concentration-dependent manner. The adenosine- and ATP-induced relaxations were suppressed by alloxazine and MRS1754, but not by 8-(3-chlorostyryl)caffeine. ARL67156 potentiated the ATP-induced relaxation but not the adenosine-induced one. MRS1754 suppressed the ATP-induced relaxation potentiated by ARL67156. CONCLUSIONS: The above results suggest that, in the CCP of rabbits, the adenosine receptor mediating adenosine-induced relaxation is of the A(2B) receptor and the ATP directly causes relaxation through the A(2B) receptor on the CCP.  相似文献   
3.
Strain difference of susceptibility to 4-nitroquinoline 1-oxide (4NQO)-induced squamous cell carcinomas of the tongue among Dark-Agouti, Long-Evans, Sprague-Dawley, ACI/Ms, Fischer 344, Donryu and Wistar/Furth rats was surveyed by evaluating the survival times, incidences and sizes of developed tumors as markers of susceptibility. Administration of 4NQO dissolved in drinking water induced squamous cell carcinomas in various sites of the upper digestive tract mucosa of all the experimental male and female rats of the seven strains. Regarding the mean survival times, Wistar/Furth rats survived much longer than any other strain of rats, and Dark-Agouti showed the shortest survival. The incidence of large, mass-type carcinomas of the tongue of Dark-Agouti rats was higher than in any other strain of rats, while that of Wistar/Furth rats was the lowest. Subsequently the mitotic activity and bromodeoxyuridine incorporation in the tongue epithelium of Dark-Agouti and Wistar/Furth rats were estimated after a short-term administration of 4NQO. There was a pronounced difference between the two strains of rats, because the proliferative responses of the tongue epithelium of Dark-Agouti rats to the 4NQO stimulation were much higher than those of Wistar/Furth rats. These results indicated that there are marked differences in the susceptibility to 4NQO-induced tongue carcinoma among the seven strains of rats, and that Dark-Agouti and Wistar/Furth rats could be useful as models of highly and poorly susceptible strains, respectively, for further genetic analysis.  相似文献   
4.
Lewis Y (Ley) antigen, a difucosylated tetrasaccharide found on type 2 blood group oligosaccharides of glycolipids and glycoproteins, is thought to be a phenotypic marker predictive of cell differentiation. The distribution of this antigen in human anagen hair follicles was examined by immunohistochemical staining using a monoclonal antibody (AH-6) to Ley. In the bulbar and suprabulbar portion of anagen hair follicles, Ley antigen was detected in the three layers of the inner root sheath. Subsequently, the positive staining became translocated to the innermost layer of the outer root sheath in the middle part of the hair follicles. In the upper portion of the hair follicles, Ley antigen was found in the outer cells of the outer root sheath. These findings suggested that the expression of Ley antigen in the anagen hair follicles was correlated with the processes of keratinization or terminal differentiation.  相似文献   
5.
Temporal Delta Wave and Ischemic Lesions on MRI   总被引:1,自引:1,他引:0  
Abstract: The present study was designed to determine the clinical significance of a temporal low-voltage irregular delta wave (TLID) on EEG. Among 808 EEG records examined during one year at our hospital, the TLID was commonly detected in patients with clinically diagnosed ischemic brain diseases such as multiple infarction. Subsequently, a relation of the TLID to ischemic lesions on MRI was examined in 50 elderly depressive patients. It was found that there was a close correlation between the occurrence of the TLID and small ischemic lesions on MRI (p<0.001). These results suggest that the TLID is a valuable indicator of minor ischemic changes of the brain.  相似文献   
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A filing system for ocular fundscopic image data was developed by using a personal computer for the Twin AMHTS. The development of the system was tried as one of the data transfer system including image data between two similar AMHTSs named the Twin AMHTS through the information network system. The filing system is capable of storing 26782 data of ophthalmoscopic pictures with a data compression mode by using a magneto-optical disk (MOD) whose storage capacity of both sides is 616 MB. It takes no long time for retrieval and display of the image data in the filing system. Good quality of compression and decompression obtained and reproducibility of the ocular fundus picture is favorable regardless of normal or abnormal cases. As a result, it is suggested that the developed system has practical utility although it requires more improvement.  相似文献   
9.
Senile aortic amyloidosis in 224 autopsy cases over 40 years was investigated comparing cardiac and pancreatic amyloidosis in them. A total of 176 cases of aortic amyloidosis was found for an average incidence of 79%. Under the 5th decade the incidence was 51% and it rose sharply with age and reached 95% in over the 8th decade. The incidence of cardiac amyloidosis also increased with age, but it was always higher in the aorta. Aortic and cardiac amyloid were both positive in the DMAB method for tryptophan. The major part exposed to amyloidosis in the aorta was the media. The medial amyloid consisted of numerous minute deposits and had no relation to atherosclerosis. Some comments about the pathogenesis of senile amyloidosis were also mentioned.  相似文献   
10.
The color reaction between partially saponified poly(vinyl acetate), (P-PVAc), which is dissolvable in water and iodine-iodide was investigated in the presence of amylose. As the concentration of amylose increases, the absorbance at λmax = 488 nm of the red-violet complex between P-PVAc and iodine-iodide decreases and, on the other hand, the absorbance at λmax = 625 nm of the blue complex between amylose and iodine-iodide increases. The equation for the relationship between the decrease in the red-violet complex and the increase in the blue complex was derived. On the basis of this equation, the molar absorption coefficient per iodine molecule at λmax = 625 nm for the blue complex of amylose with iodine-iodide was found to be 3,68·104 l mol?1 cm?1 at 15°C.  相似文献   
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