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991.
Summary In a previous study we observed that calcitonin increases -endorphin, ACTH, and cortisol secretion. We assumed that calcitonin might have a modulatory role on the pituitary function. The present study was initiated to clarify whether this effect is due to a direct pituitary stimulation or to an indirect stimulation through CRF (corticotropin releasing factor).Fourteen healthy subjects, aged 30–60 years were investigated. All the subjects received 100IU Salmon calcitonin Sandoz i.v. at 8a.m. (time 0). Plasma -endorphin, ACTH and cortisol were estimated every 30min from – 30 to 120 min by specific radioimmunoassay. The same parameters were estimated a second time, at the same intervals, when cyproheptadine 8 mg (7 subjects) and 40 mg propranolol (7 subjects) were given per os at – 30 min and calcitonin i.v. at time 0. -endorphin, ACTH and cortisol levels (Mean ±SEM) rose significantly after calcitonin (peak value at 30–90 min) from 5.2 ±0.7 to 15.1±2.6 pmol/l; from 43.0±2.7 to 70.7±4.1 pg/ml and from 10.6±1.5 to 19.6 ±2.1 g/100 ml respectively (p< 0.0001 by analysis of variance and covariance and repeated measures). Propranolol 40 mg (per os) administered at time – 30 did not alter the response of -endorphin, ACTH and cortisol to calcitonin (infused at time 0).Cyproheptadine, the antiserotonergic substance that inhibits the synthesis and release of CRF completely inhibited the stimulatory effect of calcitonin.We conclude that probably calcitonin has a modulatory role on the hypothalamo-pituitary adrenal axis and that it acts at the hypothalamic level probably by stimulating CRF secretion.  相似文献   
992.
Whether the lumbar cerebrospinal fluid (CSF) concentration gradient of monoamine metabolites found in adults is influenced by age or pubertal status was studied in 26 children ranging from 6.5 to 17.3 years of age. Homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA), and 3-methoxy-4-hydroxyphenylglycol (MHPG) were assayed by high-power liquid chromatography (HPLC) with electrochemical detection. Eight patients were prepubertal (Tanner stage I). The slopes in units of picomoles/milliliter/milliliter for regression lines for CSF monoamine metabolite concentrations versus milliliter of CSF collected were 5.07 +/- 0.65, 10.13 +/- 2.0, and 0.67 +/- 0.22 for 5-HIAA, HVA, and MHPG, respectively, for the group as a whole. Significant correlations with age, height, weight, or Tanner stage were not found for the HVA or MHPG concentration gradients. Tanner stage and 5-HIAA slope were significantly correlated. Three of eight prepubertal patients had nonsignificant 5-HIAA gradients. CSF studies in pediatric populations must control for aliquot collected, as the size of the gradient could produce differences sufficient to mimic a "positive" clinical study if the aliquots collected are not the same.  相似文献   
993.
The authors assessed the impact of the Nazi Holocaust on the course and symptoms of posttraumatic stress disorder (PTSD) among Israeli combat stress reaction casualties. They examined a sample of 96 such casualties of the 1982 Lebanon War whose parents had gone through the Nazi Holocaust and compared them to casualties who did not have such family history for 3 consecutive years beginning 1 year after their participation in the war. Results showed that 2 and 3 years after their participation in the 1982 Lebanon War, the children of Holocaust survivors, i.e., "second-generation" casualties, had higher rates of PTSD than did the control subjects, as well as a somewhat different clinical picture. Clinical and methodological implications of the findings are discussed.  相似文献   
994.
The spondylometaphyseal dysplasias are a very heterogeneous group of disorders. Only one has been clearly defined, namely, the spondylometaphyseal dysplasia — Kozlowski type, known also as the common type. This disorder is inherited as an autosomal dominant trait. In this report we describe an Arabic-Moslem kindred with spondylometaphyseal dysplasia, not of the common type, with an autosomal dominant mode of inheritance, indicating further heterogeneity.  相似文献   
995.
A study was carried out to evaluate the andrological parameters in 540 human semen specimens divided into groups according to sperm counts. The parameters were: motility percentage and grade, percentage of viability and of morphologically normal sperm and immature cells. The Duncan multiple range test and the Kruskal-Wallis test with multiple comparison of ranks were used in the statistical analyses. Of particular interest, among other our findings, were the significant differences obtained by comparing the group with sperm counts up to 5 x 10(6) per ml semen and that with counts ranging from 5.1 to 10 x 10(6) per ml semen. This was true for all parameters with the exception of semen volume. Comparison of the oligozoospermic groups (up to 20 x 10(6)/ml) with those having higher sperm counts also showed significant differences. There was a trend towards improvement of the examined parameters with the increase in sperm density, but with a remarkable heterogeneity particularly within the oligozoospermic groups. In all groups motility, viability and morphological normality of sperm showed a positive correlation with each other. "Normal values" of the parameters studied could be derived from scatterplot charts over the entire range of sperm counts and from the statistical evaluation of the grouped material.  相似文献   
996.
Four enkephalin analogs containing C-terminal 2-amino-2-phenyl-1,3-indandione residue were prepared: [Met-NHPID5]--enkephalin (E3), [D-Ala2,Met-NHPID5]--enkephalin (E4), [Leu-NHPID5]--enkephalin (E5), [D-Ala2,Leu-NHPID5]--enkephalin (E6). Their analgesic activities were assayed by three in vivo tests: the "hot plate" method, the reaction to electric painful stimulus and the writhing syndrome test. Neurotoxicity effects were determined by the rota-rod test. The most pronounced analgesic effect was induced by compounds with D-Ala in position 2, particularly in the "hot plate" test.  相似文献   
997.
Z M Wu 《中华肿瘤杂志》1988,10(5):360-363
The results of Tc-99m-PMT imaging on 100 patients with various malignant and benign hepatic diseases verified histologically (73 hepatocellular carcinoma, 3 liver cell adenoma, 1 cholangiocarcinoma, 5 metastatic liver carcinoma, 2 liver cyst, 12 hemangioma, 1 fatty degeneration, 1 liver regeneration, 1 postoperative liver fibrosis and 1 liver cirrhosis) are reported. All lesions appeared as decreased radioactivity or "cold" defect region on early Tc-99m-PMT imaging, rendering it valuable for the diagnosis of tumor localization. In 92 (95.8%) of the 96 patients with various hepatic tumors and 25 (86.2%) of the 29 patients with small hepatocellular carcinoma (less than 5 cm), the tumors were localized by early Tc-99m-PMT imaging. In 14 of the 73 patients with established hepatocellular carcinoma, the tumors gave greater radioactivity than that of the surrounding liver tissues, whereas in 31 patients the radioactivity of the tumor equalled the normal liver on delayed Tc-99m-PMT imaging (positive rate 61.6%). There was no significant difference between the positive rates of serum AFP level and the tumor size shown by delayed Tc-99m-PMT imaging in hepatocellular carcinomas. The radioactivity in 3 liver cell adenoma patients was similar to the gallbladder. No false positive result was seen in the other malignant and benign hepatic tumors. This study indicates that delayed Tc-99m-PMT imaging is highly specific in the diagnosis of hepatocellular carcinoma.  相似文献   
998.
D H Lu  Q Z Xu 《中华肿瘤杂志》1988,10(3):205-208
The sella turcica region is an anatomical site preferential for various types of intracranial tumors. Pathological analysis of 1458 cases of tumor in this region is presented. They comprised 20.16% of the intracranial tumors. Among them, 846(59.1%) were pituitary adenomas, 433(29.7%) craniopharyngiomas, 91(6.2%) meningiomas and 42(2.9%) germinomas. In pituitary adenomas, chromophobe adenoma was predominant, mixed cell adenoma next and no basophilic adenoma was observed. Of craniopharyngiomas they were divided into cystic, partly solid and cystic, and calcified types grossly and histologically into adamantinomatous, squamous and calcified types. In this kind of tumor, well differentiated cells were consistent to the clinical benign course. For meningiomas, histologically meningotheliomatous type was most common in this region. In previous reports, germinomas in the sella turcica region were so-called ectopic pinealoma. Now it is well known that this tumor arises from germ cells, hence, the synonym "ectopic pinealoma" is obsolete. The germinomas in the sella turcica region accounted for 44.68% of all intracranial germinomas. Microscopic picture of this tumor was similar to those of seminoma of the testicle and dysgerminoma of the ovary. Although gliomas, teratomas, giant cell tumors and chondromas were uncommon in the sella turcica region, the authors believe that they should be considered in the differential diagnosis of tumors in the sella turcica region.  相似文献   
999.
The article describes four design variants of the "auxiliary liver" apparatus which consists of the blood passage fractionators or plasma filters and an original mass transfer device. Indications for using this or that variant of the apparatus have been determined in relationship to the patient's weight and concomitant complications. Clinical examples are given.  相似文献   
1000.
A "round-robin" interlaboratory evaluation of a proposed American Society for Testing and Materials (ASTM) standard test method was conducted for measuring the resistance of chemical protective clothing materials to degradation by liquid chemicals. The objective of this project was to determine the relative precision of the method and, where appropriate, recommend modifications that would improve reliability. In the round-robin format, eight laboratories used the proposed method to test each of five protective clothing materials against five liquid chemicals that are widely used commercially. The resulting data revealed that the proposed test method was not stringent enough to generate acceptable levels of accuracy and precision. Both intra- and interlaboratory standard deviations showed a high degree of variability in changes for the three physical properties evaluated. Changes in the method were identified which, if implemented, should improve accuracy and precision considerably.  相似文献   
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