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31.
Autonomous hypersecretion of aldosterone (primary hyperaldosteronism) is caused by either hyperplasia (usually bilateral) or an adenoma (frequently unilateral) of the adrenal cortex. Systemic hypertension due to an aldosteronoma is a potentially curable condition through surgical extirpation of the offending organ. In our experience with 37 patients clinically suspected to have primary hyperaldosteronism, radiological methods contributed significantly in preoperative diagnosis. These included (1) selective bilateral adrenal vein catheterization and blood sample collection, (2) adrenal venography, and (3) radioisotope adrenal scan. Unilateral hyperfunction could be accurately detected by the aldosterone assays from the collected samples. When adrenal venography was technically satisfactory, a nodule or aggregate of nodules measuring at least 7 mm and located on the margin of the gland or 1.5 cm or more in diameter when located in the center of the gland were readily identified. Enlarged adrenal gland on venography, in itself, was not a dependable index of a hyperfunctioning gland. Presence of a higher uptake on one side on the radioisotope adrenal scan did not always indicate the hyperfunctioning gland, but lack of lateralization of adrenal hyperfunction was more accurately predicted on the radioisotope scan than by venography. Four histopathological patterns were recognized in the surgically removed adrenal glands, but no correlation between these patterns and clinical behavior or postoperative course was found.  相似文献   
32.
We propose that intracellular prostaglandins (PGs) are essential for the final expression of the effects of second messengers in most cells. We suggest that the amounts of PGs required are very small (in the picomolar range) and are much lower than those used in most current PG studies. We suggest that while therapeutic levels of inhibitors of PG synthetase may be adequate to block the overflow of PGs from cells, they are in most cases unlikely to reduce intracellular PGs sufficiently to test the role of such PGs. We propose that there is a basal level of PG synthesis unaffected by hormones but that above this level PG synthesis is regulated by the interplay between physiological levels of cortisol, prolactin, growth hormone and thyroid hormones. For the most part prolactin seems to stimulate PG synthesis and cortisol to inhibit it: cortisol has, however, no inhibitory effect on basal PG synthesis. In reducing prolactin-stimulated PG synthesis cortisol is 1000-2000 times more potent than indomethacin on a molar basis. We suggest that the regulation of intracellular PG levels is the mechanism of the so-called "permissive" actions of these hormones. These concepts could prove important in the understanding of many aspects of physiology and pathophysiology including diurnal and seasonal changes in hormone responsiveness. They are also relevant to the use of established drugs and the design of new ones.  相似文献   
33.
The effect of light deprivation on the flickering beta-wave was investagated. Results indicate that the flickering beta-wave is extremely reduced in the eye light-deprived for 14 to 20 days relative to the normal eye. The ratio of the second beta-wave (in a series of flickering beta-waves) to the ratio of the first beta-wave appears relatively unaffected by light deprivation, but the ratio of the fourth beta-wave to the first is significantly affected by light deprivation. The effect of light deprivation on the beta-waves evoked by a 13.4 milliambert flickering light is greater for beta-waves evoked later in the series than for beta-waves evoked earlier in the series.  相似文献   
34.
Of 96 cancers which have been detected as a result of the first annual screening of 10,470 volunteers, 46 have been clinically occult. Forty-one of these have been Stage 1 or less carcinoma, and 26 of these 41 have been minimal cancer. For the radiographic parameters used, the benefit of detecting these cancers vs. the risk of induced cancer is estimated as 103:1 and 65:1, respectively.  相似文献   
35.
Three convenience products--frozen, precooked chicken apple fritters, chicken breast fillets, and chicken patties--provided by one processor were subjectively evaluated by two taste panels of older adults, ranging in age from the sixties to middle eighties. The panelists represented a middle-income group maintaining private homes and a low-income group living in public housing. Both panels rated each product above "good" (score=4) or "fair" (score=3) on four acceptability factors and the overall score. Although mean scores of the low-income taste panel on all factors were generally higher for all products, the only significant difference (P less than .01) pertained to the appearance factor. Both panels indicated willingness to buy all three products.  相似文献   
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Of 160 patients who underwent Nissen fundoplication for treatment of symptomatic peptic reflux esophagitis, five patients (3.1%) developed gastric ulcers. Four of these five patients experienced the "gas-bloat" syndrome. All ulcers were located on the lesser curvature of the stomach. Analyses of our experience with use of various types of hiatal hernia repair suggests that creation of the valvuloplastic mechanism unique to the Nissen procedure may be of etiologic significance in the development of gastric ulcers following this procedure.  相似文献   
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The per review system for the assessment of research proposals is widely respected by working scientists. Nevertheless two problems associated with the operation of this system by the US National Institutes of Health are identified. First the scientist has no control over which committee will review an application and it may be considered by a quite inappropriate group. Second analysis of the committee composition suggests that in some of the groups several members are not active scientists and therefore not the "peers" of the applicant.  相似文献   
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