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51.
The effect of complete unilateral ureteral obstruction (CUUO) on proximal tubular functions was studied in rats, using the K+-sensitive microelectrode technique and split oil drop method. In the control kidneys peritubular membrane potential (EMperi) and intracellular potassium activity (aKi) were -70.8 +/- 7.0 mV and 81.2 +/- 22.0 mEq/liter (mean +/- SD), respectively. In the CUUO kidneys both EMperi and aKi were progressively reduced with the duration of obstruction. However, in all tubules aKi values were still above the electrochemical equilibrium. In the three days' CUUO kidneys EMperi and aKi were -51.5 +/- 11.7 mV and 53.8 +/- 22.8 mEq/liter, respectively. Rate of fluid absorption (JVL;nl./sec. mm.) across the proximal tubular epithelium from Ringer solution in the control and three days' CUUO kidneys was 0.029 and 0.0065 respectively. In the CUUO kidneys there were wide variations in JVL and EMperi, but there was a clear correlation between these two variables. JVL from choline chloride solution was negligible in both control and CUUO kidneys. From above results, it was suggested that the proximal tubular reabsorption primarily depending on the Na+-K+ pump might be reduced but still working in the CUUO kidney, and thus the proximal tubular reabsorption might take part in preservation of glomerular filtration during the obstruction.  相似文献   
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Although occult urinary blood in health examinations is common in healthy employees, in the majority with occult urinary blood usually no further examination or treatment is necessary, but occult urinary blood could be an early symptom in urinary tract malignancy. In this study the data on health examinations of male employees with occult urinary blood were analyzed from 1999 to 2002 and strategies for them were discussed. The subjects were male employees working in a steel company, 1,135 ('99), 1,077 ('00), 994 ('01) and 945 ('02). The positive ratios of occult urinary blood were 8.6% in '99, 7.6% in '00, 7.8% in '01, 8.3% in '02, respectively. Multiple logistic regression analysis showed that age and urinary protein were significant factors associated positively with occult urinary blood. In general, a man who had urinary tract malignancy would have macroscopic hematuria in the course of the disease. Therefore, in people with recurrent occult urinary blood the risk of urinary malignancy is considered to be rare. The follow-up protocol was set up for employees with occult urinary blood. For four years 6 employees were referred to specialists (5 to a urologist and 1 to a nephrologist). No significant disease, including urinary tract malignancy, was detected.  相似文献   
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For the rapid and sensitive detection of p53 gene mutations in esophageal endoscopic biopsy specimens, we combined cell sorting with the polymerase chain reaction and single-strand conformation polymorphism (PCR-SSCP) analysis. Mutations in exons 5–8 of the p53 gene were investigated by FCR-SSCF analysis using 103 sorted nuclei obtained from each endoscopic biopsy specimen of 16 patients with esophageal cancer. DNAs extracted from their respective surgical specimens were investigated by a conventional method of PCR-SSCP analysis. Mutations in the biopsy specimens were detected in 6 of the 12 aneuploid tumors but in none of the 4 diploid tumors. After tumor cell enrichment by cell sorting, one mutation in exon 8 became apparent, which could not be detected from the surgical specimen by a conventional method of PCR-SSCP analysis. This method should improve the sensitivity of detecting p53 gene mutations, and provides additional information concerning the DNA ploidy pattern in the tumors.  相似文献   
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We report the surgical results of 13 accessory nerve neurotizations in brachial plexus birth palsy. The mean age at operation was 5.9 months. The accessory nerve was transferred to three C5 roots, to three C6 roots, to four posterior division of the middle trunks, to one musculocutaneous nerve, and to two suprascapular nerves. Sixty-seven percent of the cases acquired M4 or more in the deltoid muscle, 88% in the infraspinatus muscle, and 100% in the biceps brachii muscle. Twenty-five percent of the cases acquired M4 or more in the triceps brachii muscle and the wrist extensor muscles. These results were much better than formerly reported for adult cases by other authors. No functional compromise of the trapezius muscle was noted. The accessory nerve neurotization can be used safely and effectively in neurosurgical reconstruction of the brachial plexus palsy in infants. © 1994 Wiley-Liss, Inc.  相似文献   
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韩素莉  斋藤健 《卫生研究》1994,23(6):328-330
给大鼠经气管分别注入4、16、64mg石英粉尘生理盐水混悬液。在染尘后第7,15和30天解剖动物,测定血浆中Cu、Zn,Mn、Mo、Si、Rb和Sr等7种微量元素的含量。实验结果表明,随着染尘剂量的增加,血浆中铜的含量明显增高,呈正相关,相关系数为0.999。而血浆锌的含量随着染尘剂量的增加而明显的降低,呈负相关,相关系数为-0.998。血浆中Mo、Mn、Si、Rb和Sr含量与对照组比无明显差异。  相似文献   
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BACKGROUND: Nevic corpuscle (NC), a stacked lamellar structure reminiscent of Meissner corpuscle, is frequently observed in dermal melanocytic nevi. Although the heading 'neurotized' is classically used for these nevi, the exact neural nature of NC has been a topic of considerable debate. Neurotized nevi have received little attention in the dental literature, and there was no information on NC in oral melanocytic nevi. METHODS: Six cases of oral intramucosal nevi with a significant number of NC (two completely and four partially neurotized nevi) were examined immunohistochemically and ultrastructurally. RESULTS: NC was composed of closely piled laminar cells devoid of visible melanin. NC and associated spindle nevus cells were immunopositive for S-100 protein but negative for HMB-45, myelin basic protein and epithelial membrane antigen. Within NC, no reactivity for neurofilament protein, protein gene product 9.5 or peripherin was evident. Numerous CD34-positive dendritic cells were located between nevus cells and often encircled NC. Ultrastructurally, NC consisted of concentrically layered elongated cells with a slender lamellated cytoplasm rich in thin filaments and pinocytotic vesicles. Their cytoplasmic processes were focally covered by external basal lamina and continuous to spindle nevus cells. Occasional NC cells contained a few melanosomes. There was no interposed axon in NC. CONCLUSIONS: Despite the close resemblance to Meissner corpuscle, NC showed no axonal supply. NC cells lacked terminal Schwannian differentiation and appeared to be modified melanocytes with some perineurial ultrastructural characteristics. The presence of CD34-positive cells, presumably corresponding to endoneurial fibroblasts, further supports an organizational relationship of NC and peripheral nerve sheath elements.  相似文献   
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