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We have systematically investigated the involvement of endogenous opioids in gonadotropin secretion during primate sexual maturation by examining LH/FSH responses to gonadotropin-releasing hormone (GnRH) and changes in LH secretion during infusions of saline or naloxone, an opiate antagonist, in ten male chimpanzees between one and nine years of age. Animals were anesthetized with ketamine (10 mg/kg) and injected or infused IV with GnRH, naloxone or saline. Circulating levels of serum LH were elevated to the same extent (approximately 400%) in response to GnRH (100 micrograms) in animals 1-5 years old (juvenile) and in animals 6-9 years old (pubertal). No differences were noted between the two groups in GnRH-stimulated levels of serum FSH. During treatment with naloxone (0.14 mg/kg bolus followed by 0.2 mg/kg/h maintenance infusion for 3 h), serum LH levels in pubertal animals were significantly (p less than 0.05) elevated by as much as 95% over LH levels found during treatment with saline. Juvenile animals, on the other hand, failed to demonstrate significant increases in serum LH following naloxone at the doses tested. A strong correlation (r = .84) was found between circulating testosterone and serum LH levels during naloxone treatment. These data indicate that opioid inhibition of LH secretion can be reversed by naloxone only when puberty is reached in chimpanzees and suggest an alteration in opioid regulation of GnRH near the time of puberty. The strong correlation between testosterone levels and LH responses to naloxone suggests that steroids may participate in the maturation of opioid control of LH during puberty of nonhuman primates. 相似文献
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Thomas T. Tang Harry T. Whelan Glenn A. Meyer Douglas R. Strother Ellen L. Blank Bruce M. Camitta Ralph A. Franciosi 《Child's nervous system》1991,7(8):458-461
An optic chiasm glioma may cause loss of vision, endocrine disturbances, hydrocephalus and cerebral ischemia due to its proximity to the pituitary, hypothalamus, III ventricle and internal carotids. A 3-month-old infant with optic chiasm glioma developed hypopituitarism and inappropriate secretion of antidiuretic hormone with plasma hypo-osmolality. The cerebrospinal fluid (CSF) protein concentration was markedly elevated. The impairment of fluid absorption via arachnoid villi and peritoneum by the high protein content, and reversed osmotic gradient between protein-rich CSF and hypo-osmolar plasma may have contributed to both nonobstructive hydrocephalus and recurrent ascites following ventriculoperitoneal shunting. Cerebral ischemia from carotid compression may have led to cerebral atrophy. 相似文献
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Bradley R Pieters Johan N B van der Grient Leo E C M Blank Kees Koedooder Maarten C C M Hulshof Theo M de Reijke 《Radiotherapy and oncology》2006,80(1):69-72
Catheters were developed that can be fixed in the prostate gland by self-expanding parts for use in PDR brachytherapy. Daily CT-scans were made to investigate the magnitude of catheter displacement. The mean absolute displacement during the 3 day treatment was 1.2 mm. The resulting minor alterations in dose-volume parameters were of no clinical importance. 相似文献
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Dr. Adolf Blank 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1929,122(4):661-667
Ohne Zusammenfassung 相似文献
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A L Harjula J C Baldwin N E Silverman N Blank P E Oyer E B Stinson N E Shumway 《The Journal of cardiovascular surgery》1990,31(1):1-6
Implantation response has been a critical problem following heart-lung and lung transplantation. While the precise etiology of this problem remains unclear, improvements in organ preservation would be expected to have a beneficial effect on implantation response. The time-related profile of the implantation response was studied in 20 patients who underwent heart-lung transplantation between March 1984-March 1987. In 10 operations the donors had intravenous prostaglandin E-1 pretreatment while 10 had no vasodilatation before explantation of the organs. Otherwise lung preservation and early (2 weeks) immunotherapy were similar in both groups. The implantation response was evaluated by chest films and postoperative lung functions and mechanics. Roentgenographic implantation response was evident from the first postoperative day, was less evident at the seventh postoperative day and then gradually increased during the second postoperative week. There was a tendency towards less implantation response in the PGE-1 group than in the control group, but no statistical difference was observed. Patients with severe operative bleeding problems were excluded from the study. Only peak inspiratory pressures were significantly higher in the control group than in the PGE-1 group (p less than 0.01). Other lung function studies (alveolar-capillary pO2 difference, extubation time) were not different in the groups. This study supported the hypothesis that prostaglandin E-1 may have salutary effects on graft preservation and implantation response in heart-lung transplantation. Since 1986, we have performed 16 heart-lung transplantations using graft preservation with PGE-1 and flush perfusion. Thirty-day mortality is 0% and 13 of 16 patients are surviving. 相似文献
10.
Chest radiographs and chest computed tomography (CT) scans were compared in 203 patients with newly diagnosed Hodgkin disease. The incidence of positive findings was tabulated from six intrathoracic lymph node groups, lung parenchyma, pericardium, pleura, and chest wall. The discordant cases were assessed to determine impact on clinical management. The CT scans provided additional evidence of disease involvement, ranging from 0% to 15% at each of the designated anatomic sites. Treatment was altered in 9.4% of all patients (19 of 203), including 13.8% (nine of 65) of those undergoing radiation therapy alone and 8.2% (ten of 122) of those undergoing combined-modality treatment. We conclude that routine chest CT examinations are valuable in the clinical management of those patients for whom radiation therapy is planned. 相似文献