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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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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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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
7.
An outbreak of hypervitaminosis D associated with the overfortification of milk from a home-delivery dairy. 总被引:3,自引:1,他引:2
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OBJECTIVES. The purpose of the study was to identify cases of hypervitaminosis D caused by the inadvertent overfortification of milk from a home-delivery dairy and to identify risk factors for this illness. METHODS. Hospital discharge, laboratory, and state health department data were used to define, identify, and describe cases of hypervitaminosis D diagnosed in the exposed communities between January 1, 1985, and June 30, 1991. To identify disease risk factors, community-based sex- and age-matched controls were used in a case-control study. RESULTS. Of the 56 case patients identified, at least 41 were hospitalized; 2 died. The study included 33 case patients and 93 control subjects. Nineteen of the 33 case patients had been customers of the implicated dairy. Risk of illness rose with increasing consumption of the dairy's milk and was also associated with vitamin D supplement use, sunburn susceptibility, and cancer history. Accounting for these factors did not alter the association between drinking the dairy's milk and developing hypervitaminosis D. CONCLUSIONS. Overfortification of milk with vitamin D can lead to hypervitaminosis D, manifested by severe illness and death. The episode highlights the need for monitoring the fortification process and enforcing the upper limit for vitamin D addition to milk. 相似文献
8.
C A Blank J E Nagel W H Adler F J Heldrich 《Maryland medical journal (Baltimore, Md. : 1985)》1989,38(9):739-742
A varicella infection in a previously healthy young girl was complicated by bacterial sepsis, arthritis, and osteomyelitis in multiple locations. This secondary complication caused by Staphylococcus aureus was associated with a transient defect in granulocyte function and an alteration in the representation of CD4 and CD8 positive lymphocyte subpopulation. The mechanism responsible for secondary bacterial infections following varicella may be due to transient defects in granulocyte function. 相似文献
9.
I H Blank 《The Journal of investigative dermatology》1992,98(3):265-268
Private-sector funding of biomedical research within academia may come from industry, foundations, the dermatologists themselves, and the public at large. Industry-funding is of benefit to both academia and industry. Industry may fund clinical and basic research and product testing. Industry is more willing to fund product testing and clinical research than basic research. Funds for dermatologic research may be obtained from manufacturers of drugs, medical devices, cosmetics, soaps, and detergents. Questions of academic freedom arise when research is funded by industry. The results of academic research are in the public domain; the results of intramural industry research are often proprietary, i.e., "trade secrets." When there is industry funding within academia, any restraints on publication should be held to a minimum and be temporary. Publication should occur in a timely fashion, although recognizing the need for delayed publication if the results concern patentable material. When there is a consultantship, pre-arranged terms of agreement may restrict communication. Patents usually are held by the investigator's institution. The funding company may be granted world-wide, royalty-bearing licenses. Conflicts of interest may arise during any research endeavor; this warrants close attention when the research is industry funded. Stock ownership, speaker fees, blind contracts, etc., should be avoided. In any communication, funding agreements should be stated. Indirect costs are a "necessary evil." There are non-research expenditures associated with all research projects for which the institution is justified in requesting compensation. Indirect costs must have definite connections to a project. As industrial funding of research within academia increases, various facets of the academia-industry relationship are receiving increasing attention. Several aspects of conflicts of interest and indirect costs must yet be resolved. When faced openly and directly, all of these issues are manageable and need not reduce the benefits to both industry and academia that are inherent in this relationship. Federal funding of academic research uses tax dollars; industry funding comes from private capital. Academia will benefit from the funding of academic biomedical research by industry. The ultimate beneficiary of the funding of academic research by industry, however, will be society at large as the medical advances derived from sound biomedical research and carefully controlled clinical trials aid patients. A solidly established academia-industry relationship is essential to the effective funding by industry of biomedical research within academia. 相似文献
10.
T O Blank 《International journal of aging & human development》1989,29(3):225-239
Two world views-mechanism and organicism-have dominated the youthful history of social psychological study of adult development and aging. Despite differences, both assume a stable, universal, transhistorical structure underlying social psychology; the goal of research is to discover and delineate such universals. A third world view, contextualism, begins with an assumption that action and thought are developed within relationships, which form the contexts for particular actions. It stresses the negotiated, constructed nature of "reality,"the historical embeddedness and unique quality of action as it unfolds, and the importance of negotiation making use of multiple perspectives. The approach and contextualist goals are significantly different from more typical approaches. Three areas of research in social gerontology and social psychology-environmental relations, attribution, and social relations in a social reconstruction/social breakdown model-illustrate a contextualist approach. Control and a "voice" in a negotiation of relationships and the characteristics of one's contexts are central to a contextual approach to all three. 相似文献