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We examined the activity of spermidine/spermine N 1-acetyltransferase (SAT), a rate-limiting enzyme of the biodegradation of polyamines, in N -butyl- N -(4–hydroxybutyI)nitrosamine-induced transitional cell carcinoma (TCC) and melamine-induced papillomatosis of rat bladder, and compared the activity to that of ornithine decarboxylase (ODC). Both activities were higher in both lesions than in control rats. The difference between SAT and ODC activities in cancerous tissue and papillomatosis was not significant. Cells stained for proliferating cell nuclear antigen (PCNA) were abundant in papillomatosis. TCC had areas with much PCNA. The results indicated that an elevation of SAT activity occurs in both reversible and irreversible proliferation of bladder epithelium and could be important in bladder carcinogenesis.  相似文献   
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We report a 52 year-old man presenting with an acute considerable hair loss induced by carbamazepine (CBZ). The remarkable scalp hair loss started within a week after CBZ administration. There was no evidence of dermatitis or allergic reaction, or other cause for the hair loss. The serum concentration of CBZ was 8.6 microg/ml (therapeutic range 8-12 microg/ml). CBZ was discontinued, and the hair loss stopped within several days with new hair growth. Medication-induced hair loss is an occasional adverse effect of many drugs used for neuropsychological diseases. CBZ also induces hair loss and its frequency was reported below 2%. Only a limited number of detailed case reports describing CBZ-induced hair loss were available, and we found these cases could divide into two groups with regard to a delay in starting hair loss after administration of CBZ. In one group, the hair loss started within a week suggesting anagen effluvium and in another it started after two or three months suggesting telogen effluvium. This finding suggests the causative mechanism of CBZ-induced hair loss is not unitary.  相似文献   
15.
A 48-year-old man presented with malignant hypertension and massive proteinuria. Renal angiography showed complete obstruction of the left renal artery and 99mTc-mercaptoacetylglycine (MAG3) renography showed a nonfunctioning left kidney. Percutaneous transluminal renal angioplasty of the left renal artery was unsuccessful; hence, the patient underwent left nephrectomy because of uncontrolled hypertension and proteinuria. Histological examination of a right kidney specimen revealed lesions of focal segmental glomerulosclerosis with benign nephrosclerosis. In contrast, histology of the left kidney showed typical ischemic kidney with hypertrophy of arteriolar smooth muscle cells. The patient responded favorably to the nephrectomy, as his blood pressure and urinary protein dramatically decreased with no antihypertensive medication. This case illustrates the heterogeneous effect of the renin-angiotensin system on either kidney in patients with renovascular hypertension due to unilateral renal artery stenosis.  相似文献   
16.
In 29 cases undergoing lung resection, effects of the surgery on left ventricular function were investigated indirectly with a Nuclear Stethoscope. Various parameters were measured following an exercise load before and after surgery. There were significant decreases in post-operative resting levels of stroke volume (SV) (p < 0.001), end-diastolic volume (EDV) (p < 0.001), ejection fraction (EF) (p < 0.05) and ejection rate (ER) (p < 0.001) and significant increase in heart rate (HR) (p < 0.001) when compared to pre-operative resting levels. Neither filling rate (FR) nor cardiac output (CO) showed significant difference. At maximum exercise load, there were significant decreases in post-operative EDV (p < 0.005), SV (p < 0.005), ER (p < 0.001) and FR (p < 0.005), but no significant differences were detected in HR and EF; consequently, there was a significant decrease in CO (p < 0.005). Ratio of the levels at maximum load to those at resting of each parameter did not show significant difference between before and after operation with regard to any parameters except CO and FR which showed significant decrease (p < 0.005 and p < 0.001, respectively). Effects of the surgery on left ventricular function were studied according to amount of lung resection. In 13 cases where more than two lobes were resected, similar significant differences to those mentioned above were found in all parameters except EF. In cases where a single lobe was resected, only ER and FR showed similar tendency to that described above. Effects of the surgery on left ventricular function were also studied according to age of patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
17.
Hypertension after extracorporeal shock wave lithotripsy (ESWL) has been a controversial subject. Changes in blood pressure were studied in 262 patients (mean age 47.8 years) 18.6 months after ESWL. According to World Health Organization criteria the number of patients who showed a decrease exceeded those who showed an increase in blood pressure. The patients who have been on antihypertensive therapy showed a significantly greater decrease in blood pressure than those without medication. Of 192 normotensive patients diastolic pressure increased 1.2 mm. Hg and 2 (1.0%) had hypertension 18.4 months after ESWL. Annualized increase in diastolic pressure and new onset of hypertension were calculated to be 0.78 mm. Hg and 0.65%, respectively. Significant elevation of diastolic pressure was noted in the patients who received a larger number of shock waves. Blood pressure should be carefully followed after ESWL especially in patients who have been treated by a greater number of shock waves.  相似文献   
18.
Purpose  To determine the efficacy of intravitreal injection of sulphur hexafluoride (SF6) gas for reducing persistent subfoveal fluid after scleral buckling surgery for macula-off rhegmatogenous retinal detachments. Methods  We injected 0.3 ml of SF6 gas into the vitreous cavity of two eyes of two patients with persistent macular retinal detachment 3 and 5 months after successful scleral buckling. Optical coherence tomography was performed before and after surgery. Results  Subfoveal fluid was displaced peripheral to the fovea immediately after gas injection and the fluid was absorbed gradually in both eyes. Conclusions  Persistent subfoveal fluid after scleral buckling may be treated with intravitreal SF6 gas injection. The authors have no proprietary interest in any aspect of this report  相似文献   
19.
Lmmunohistochemical analyses were made of the superoxide dismutases (Mn-SOD and CuiZn-SOD) in biopsied muscles from 7 patients with mitochondrial encephalomyopathies that included mitochondrial encephalomyopathy, lactic acidosis and strokelike episodes (MELAS), and chronic progressive external ophthalmoplegia (CPEO). Mn-SOD mainly was present in the subsarcolemmal region, but it also was found in a coarsely granular, reticular, or diffuse pattern of staining within the muscle fibers. These Mn-SOD-positive fibers corresponded almost completely to the ragged-red fibers. The immunoreaction for CuiZn-SOD was weakly positive in some of the muscle fibers positive for Mn-SOD. In CPEO, Mn-SOD-positive fibers predominantly showed decreased cytochrome c oxidase (COX) activity. In MELAS, Mn-SOD-positive fibers tended to be stained deeply for COX although a few were COX-negative. These findings suggest that Mn-SOD-positive fibers can be used to make a differential diagnosis between CPEO and MELAS and that in mitochondrial encephalomyopathies Mn-SOD in the raggedred fibers may protect against oxidative stress. © John Wiley & Sons, Inc.  相似文献   
20.
We performed human leukocyte antigens(HLA)typing for class I antigens on 19 Japanese patients with Fisher's syndrome. We demonstrated a statistically significant association between the disease and the HLA-B39 antigen.  相似文献   
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