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61.
Oxyphil cells and oxyphil cell adenomas of parathyroid glands are, in most instances, regarded to be nonfunctioning. Although 21 cases of hyperparathyroidism associated with parathyroid oxyphil cell adenoma have been reported, secretion of hormone by these tumors has not been conclusively demonstrated. A parathyroid adenoma, diagnosed by light microscopy as oxyphil type, together with the results from ultrastructural and biochemical studies of the patient's adenomatous tissue, are reported here. The patient, a 64-year-old male, was found to have elevated serum calcium, low serum phosphorus, and elevated serum immunoreactive parathormone: findings consistent with hyperparathyroidism. After excision of two small normal-appearing glands and one greatly enlarged (1.9 g) parathyroid gland, those laboratory values returned to normal. Light microscopy of the enlarged parathyroid indicated that it consisted almost entirely of an oxyphil adenoma. Electron microscopy revealed that the adenoma was composed mainly of mitochondria-rich oxyphil cells but also of interspersed transitional oxyphil cells and rare scattered chief cells. Golgi zones, rough endoplasmic reticulum, and prosecretory and secretory-like granules were observed in some oxyphil cells, in most transitional oxyphil cells, and in the infrequent chief cells. Thus, many of these cells appear to contribute to the production and secretion of parathormone. Biochemical studies performed directly on the adenomatous tissue demonstrated that it was able to synthesize proparathormone and parathormone, although the proportion of hormonal peptide synthesis relative to that of the total protein synthesis in this tissue was much smaller (0.9%) than that found in normal parathyroid tissue (5.7%). There was a small increase in immunoreactive parathormone when the adenoma tissue was incubated in a low-calcium medium. These findings indicate that this oxyphil adenoma of the parathyroid gland synthesized and secreted parathormone, apparently to some extent autonomously, but suggest that its capacity to do so was largely dependent on its component of cells other than fully developed oxyphil cells, such as transitional oxyphil cells. 相似文献
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63.
Yu. A. Pirogov A. A. Ivankovskii I. P. Davydov N. P. Kabashnyi R. O. Shcherbina A. P. Nagornyi Yu. I. Zimin N. V. Leushin V. N. Kustov 《Refractories and Industrial Ceramics》1981,22(1-2):67-69
Conclusions A composition consisting of mullite corundum ramming compound MMK-72 was developed for making the bottoms of steel casting and intermediate (donkey) ladles of the converter shop of the Azovstal' factory; it was prepared from high-alumina chamotte and kaolin with a bond of orthophosphoric acid. Using the standard TU 14-297-17-78, the production of the compound is being organized at the Zaporozhe factory. The MMK-72 compound is being introduced in the converter shop of the Azovstal' factory.Translated from Ogneupory, No. 2, pp. 12–13, February, 1981. 相似文献
64.
Regional blood flow of the gastrointestinal (GI) tract and cardiac output have been determined in male Sprague-Dawley rats weighing from 30-726 g. The cardiac output (ml/min per kg) was highest in rats weighing 80-100 g. In heavier rats the cardiac output decreased proportionally with the body weight. The gradient of blood flow to the different parts of the GI tract develops step by step. In the weaning period the blood flow (ml/min per g tissue) through the stomach was less than that through the distal parts of the GI tract. However, the blood flow through the small intestine, cecum and large intestine was uniform at this age. In rats weighing 80-100 g the blood flow through both the cecum and large intestine was less than that through the small intestine. The gradient in blood flow through the various segments of small intestine developed last. 相似文献
65.
A. Z. Bagerman V. I. Guseva A. A. Zhivushkin V. P. Zimin A. B. Lebedev B. K. Pisarev V. V. Timofeev 《Protection of Metals》2001,37(1):77-79
A similarity parameter for the high-temperature sulfur corrosion of heat-resistant alloys is suggested. This parameter allows to put in order published experimental data of different authors. Original data on the weight loss by 826, -70, 26, and several materials for protective coatings also correlate with the similarity parameter. The dependences thus obtained allow to predict the operation life of materials (by their weight loss) and to rank nickel-based alloys by their corrosion resistance, depending on their elemental composition. 相似文献
66.
为了研究入渗水头对注射灌土壤水分运移及分布特性的影响,通过室内注射灌入渗模拟试验,测定了不同入渗水头下注射灌的累积入渗量、湿润锋运移距离和土壤剖面的含水率。研究表明:注射灌的累积入渗量与时间呈幂函数关系,入渗水头越大,相同入渗时间的累积入渗量越大。土壤湿润锋近似为圆心在出水口偏下的半圆形,湿润锋随时间延长运移速度变缓。在出水口下方土壤湿润范围比出水口上方大,土壤含水率也较大。入渗水头越大,相同入渗时间的土壤湿润范围越大,相同位置的土壤含水率越高。本研究结果丰富了注射灌理论,为入渗水头的选择提供参考。 相似文献
67.
在上海地区,当地下隧道覆土达到一定深度后,盾构机将穿越地质⑥层硬塑黏土层,⑦1、⑦2层砂性土层,以实际施工中所出现的困难为例,介绍了在盾构机设备、技术、操作上寻找到的相应的解决办法,对其他类似工程有一定借鉴意义. 相似文献
68.
69.
F Jónsson P Madsen LG J?rgensen M Lunding NH Secher 《Canadian Metallurgical Quarterly》1996,158(44):6256-6259
Indices of fluid balance were evaluated during and after aortic surgery in 16 consecutive patients. Thoracic electrical impedance (TI), heart rate (HR), central venous (CVP), pulmonary artery mean (PAMP), pulmonary wedge (PWP) and mean arterial (MAP) pressures as well as fourteen arterial and venous blood gas variables were followed. Consistent with a reduction of TI during the operation, fluid balance was in excess, and it remained elevated on the first postoperative morning. The HR, MAP and PWP remained stable, while CVP and PAMP decreased. Of the determined variables only TI revealed a meaningful correlation to fluid balance (rho = -0.41; p < 0.01). The results indicate that while central venous and pulmonary artery mean pressures gave the impression of a volume deficit, the positive fluid balance was mirrored by thoracic electrical impedance. 相似文献
70.
DM Clark PM Salkovskis LG Ost E Breitholtz KA Koehler BE Westling A Jeavons M Gelder 《Canadian Metallurgical Quarterly》1997,65(2):203-213
Cognitive accounts of panic predict that panic disorder patients will be particularly prone to misinterpret autonomic sensations. Several studies have produced results consistent with this prediction, but each is open to alternative interpretation. To clarify matters, 2 studies administered the Body Sensations Interpretation Questionnaire (BSIQ) to panic patients and controls. Panic patients were more likely to interpret ambiguous autonomic sensations as signs of immediately impending physical or mental disaster and were more likely than other anxiety disorder patients and nonpatients to believe these interpretations. In a 3rd study, a brief version of the BSIQ was shown to have satisfactory test-retest reliability, to change with treatment, and to discriminate treatments that varied in their effects on panic. 相似文献