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61.
LL Lindley BM Reininger ML Vincent DL Richter RP Saunders L Shi 《Canadian Metallurgical Quarterly》1998,68(5):205-212
A random-digit dialed telephone survey was conducted in a traditionally conservative southern state to determine the level of support for sexuality education in the public schools including support for specific sexuality education topics, the earliest grade level at which each topic should be taught, and the amount of instruction time required for sexuality education in the high schools. Survey data were obtained from 534 South Carolina registered voters in late January/early February 1997. Results demonstrated that most South Carolina registered voters: 1) supported sexuality education in the public schools; 2) supported instruction on a variety of sexuality education topics; 3) supported instruction at all grade levels, especially beginning in middle school; and 4) believed instruction time for sexuality education in the high schools should either remain the same or be increased. In addition, a significant increase in support for sexuality education occurred from the beginning of the survey to the end, suggesting that the instrument itself may have served as an educational tool for respondents. The characteristics of registered voters who supported sexuality education at the beginning of the survey and at the end were examined and compared. These results may assist in the development of educational and marketing strategies designed to build support for school-based sexuality education programs in South Carolina and elsewhere. 相似文献
62.
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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W Pawlik LL Tague BL Tepperman TA Miller ED Jacobson 《Canadian Metallurgical Quarterly》1977,233(3):E219-E224
Studies were conducted in anesthetized dogs to determine whether the mesenteric vasodilator response to histamine is mediated by H1 receptors alone or whether H2 receptors are also involved in the response. Evidence favoring a role for both receptors included: 1) the vasodilator response to histamine was inhibited by either the H1-receptor antagonist, tripelennamine, or the H2-receptor antagonist, metiamide; 2) both the H1 agonist, 2-methylhistamine, and the H2 agonist, 4-methylhistamine, induced dilator responses in the mesenteric circulation; and 3) two temporal patterns of vasodilation could be distinguished, namely a transient spike and subsequent fade of blood flow (seen with either the H1 agonist or with histamine after H2-receptor blockade) and a sustained and stable increase in flow (seen with either the H2 agonist or with histamine after H1 blockade). Metiamide appeared to be a potent inhibitor of the mesenteric vasodilator response to histamine at least equal to tripelennamine. 相似文献
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Cognitive performance in conversion hysteria 总被引:1,自引:0,他引:1
In order to test some neurobiologically based assumptions pertaining to attention and memory dysfunction in conversion hysteria, a series of tasks was given to 17 hospitalized patients with hysterical conversion reaction and to a control group of nonpsychotic patients under conditions of nonstress and stress. The results indicated significant differences in performance between hysteria and control subjects. The former group, in comparison to controls, had heightened suggestibility, greater field dependency, and greater impairment of recent memory and vigilance-attention. A discriminant analysis indicated the feasibility of using such tests as objective diagnostic criteria for hysteria. 相似文献
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A new analytical model was developed to estimate the degree of mutual influence of the links between the stations of Wi-Fi Mesh networks which use different channel access methods specified by the IEEE 802.11s standard, namely, contention-based channel access mechanism and the deterministic channel access mechanism based on the preliminary reservation of channel resources. The model was used to compare the efficiency of different backoff counting methods proposed in the paper for providing the interaction between two channel access methods. Additionally, the model was also used to analyze the effect of different techniques for arranging the time intervals reserved by means of the deterministic channel access mechanism on the performance of stations using contention-based channel access mechanism. 相似文献
70.