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1.
Pharmacological interactions between serotonin and dopamine on behavior in the squirrel monkey 总被引:2,自引:1,他引:1
The behavioral effects of GBR 12909, a selective dopamine uptake inhibitor, were determined in squirrel monkeys trained to
respond under a fixed-interval (FI) schedule of stimulus termination and a second-order schedule of IV drug self-administration.
Intermediate doses of GBR 12909 increased FI response rate markedly, and the highest dose decreased response rate below control
values. The 5HT uptake inhibitors, alaproclate and fluoxetine, and the 5HT agonist, quipazine, attenuated the behavioral-stimulant
effects of GBR 12909, whereas the 5HT2A/2C antagonist, ritanserin, enhanced the behavioral-stimulant effects of the lowest dose. GBR 12909 reliably maintained self-administration,
and ritanserin increased response rate maintained by the highest dose. The dopamine agonist, quinpirole, increased FI response
rate in only one of three subjects, and ritanserin enhanced the behavioral-stimulant effects of quinpirole in that subject.
The dopamine agonist, apomorphine, only decreased FI response rate, and ritanserin did not alter its behavioral effects. The
pharmacological profile of GBR 12909 administered alone and in combination with selective 5HT drugs in the present study was
similar to that obtained previously with cocaine, further demonstrating that 5HT can reliably modulate the behavioral effects
of psychomotor stimulants with prominent dopaminergic actions.
Received: 9 July 1996 / Final version: 22 November 1996 相似文献
2.
Carol E. Golin Katherine Tiller E. Byrd Quinlivan Catherine A. Grodensky Maureen Boland 《AIDS and behavior》2007,11(1):72-83
The epidemiology of HIV infection in the US in general, and in the southeast, in particular, has shifted dramatically over the past two decades, increasingly affecting women and minorities. The site for our intervention was an infectious diseases clinic based at a university hospital serving over 1,300 HIV-infected patients in North Carolina. Our patient population is diverse and reflects the trends seen more broadly in the epidemic in the southeast and in North Carolina. Practicing safer sex is a complex behavior with multiple determinants that vary by individual and social context. A comprehensive intervention that is client-centered and can be tailored to each individual’s circumstances is more likely to be effective at reducing risky behaviors among clients such as ours than are more confrontational or standardized prevention messages. One potential approach to improving safer sex practices among people living with HIV/AIDS (PLWHA) is Motivational Interviewing (MI), a non-judgmental, client-centered but directive counseling style. Below, we describe: (1) the development of the Start Talking About Risks (STAR) MI-based safer sex counseling program for PLWHA at our clinic site; (2) the intervention itself; and (3) lessons learned from implementing the intervention. 相似文献
3.
OBJECTIVE: To determine if conventional sperm parameters, specific characteristics of sperm motion determined by computer-aided semen analysis (CASA), sperm penetration assay (SPA), and/or spontaneous acrosome reaction assay could best predict fertility outcome after intrauterine insemination (IUI) from frozen donor sperm. DESIGN: A retrospective analysis of 2,245 cycles of therapeutic donor IUIs were initially studied; 1,147 cycles that met selection criteria were used in this report. SETTING: A university-based assisted reproductive technology center. PATIENTS, PARTICIPANTS: All IUIs were performed on women with documented patency of at least one fallopian tube, ovulatory cycles, and who did not receive human menopausal gonadotropins. Sperm donors had to be used for at least four different recipients (mean of 15) and at least 14 different cycles of insemination (mean of 41). INTERVENTIONS: None. MAIN OUTCOME MEASURE: Pregnancy. RESULTS: Statistical comparisons were made between donors of different relative fertility by using the Mann-Whitney test, Spearman's rank correlation, and multiple regression analysis. These analyses demonstrated that the most significant predictors of the fertility of frozen-thawed donor sperm were curvilinear velocity, straight line velocity, and the total number of motile sperm inseminated. The number of sperm with spontaneous acrosome reactions negatively correlated with fertility outcome, and SPA provided no predictive value. CONCLUSIONS: Our study supports the hypothesis that the study of sperm motion characteristics using CASA after thawing and washing of cryopreserved sperm is a better predictor of fertile outcome after IUI than analysis of fresh semen. 相似文献
4.
OBJECTIVE: To test, using a primate model, a new approach for achieving individualized pituitary-ovarian responses to controlled ovarian hyperstimulation. DESIGN: Normal ovulatory adult monkeys were selected and randomly assigned to one of the three groups according to onset of spontaneous menses. They had no prior exposure to gonadotropin-releasing hormone (GnRH) antagonist or exogenous gonadotropin therapies. SETTING: The laboratories of The Jones Institute for Reproductive Medicine were used. PATIENTS, PARTICIPANTS: Normal adult macaque females were studied. INTERVENTIONS: Monkeys received hormonal therapies of gonadotropins in combination with GnRH antagonist. MAIN OUTCOME MEASURE(S): Pituitary luteinizing hormone (LH) secretion and ovarian estrogen and progesterone production were monitored. RESULTS: Adding GnRH antagonist to ongoing human follicle-stimulating hormone (hFSH) stimulation can prevent unwanted LH surges, whether begun at early, mid, or late points in the stimulation protocol. CONCLUSIONS: The flexible protocol for administration of hFSH with GnRH antagonist yielded satisfactory results, with apparent advantages of economy, convenience, and individuality of treatment compared with GnRH agonist plus gonadotropin regimens used currently. 相似文献
5.
Said B Iskandar Mathew G Mathai Ryland P Byrd Thomas M Roy 《The Journal of asthma》2004,41(3):337-342
Asthma affects 5%-10% of adults in the United States. Older adults (> 65 years) with asthma have higher rates of fatal asthma than younger adults. The occurrence of a respiratory emergency, such as status asthmaticus, would seem likely to create a situation of cardiopulmonary dysfunction conducive to myocardial ischemia. However, multiple studies of fatal or near-fatal asthma have failed to incriminate myocardial infarction as a contributing factor. We report a patient without underlying coronary artery disease who sustained myocardial injury consistent with myocardial ischemia and infarction during status asthmaticus while receiving recommended treatment without intravenous sympathomimetics or theophylline. 相似文献
6.
Successful outcomes of hip arthroscopy are most clearly dependent on selecting appropriate patients. The indications are numerous and continue to evolve. These indications are summarized in this report. The anatomic architecture of the hip region imposes unique challenges to performing this procedure. As a surgeon’s experience evolves, so will his or her indications for this operation. It is imperative to be knowledgeable about the technique, to exercise care with the procedure, and to be certain that it is being performed for proper reasons. 相似文献
7.
Abstract Home visiting is a central, long-standing, and yet theoretically underdeveloped public health nursing process. The general aim of this study was to expand and refine a preliminary model of home visiting A stylized field research investigation was conducted in the area of maternal-child health with one nurse in a visiting nurse association in New England. A specific type of home visiting, identified as child focused, emerged, with phases labeled as surveying and designating; selling and scheduling; approaching the home and the visit; entering the home; gaining permission to ask questions and access the infant—starting with the mother's expressed concerns; making the caregiving judgment—asking questions and weighing and examining the infant; and ending the visit. "Haunting and telling" was an additional phase for certain visits. The nurse conducted child-focused home visiting in three patterns. The single pattern is described in this article. Potential maternal, child, interactive, and environmental consequences were identified, as were factors influencing the process of maternal-child home visiting. Social exchange theory emerged as useful in describing how the nurse initiated, maintained, and ended the home visiting process, and in describing attendant client consequences. 相似文献
8.
Desiree A Byrd Pegah Touradji Ming-Xin Tang Jennifer J Manly 《Journal of the International Neuropsychological Society》2004,10(3):401-411
Shape and letter cancellation test performance was investigated among large samples of African American, Hispanic, and White non-demented elders. Ethnic minority elders took significantly longer to complete both tasks compared to Whites. An index of task efficiency, which simultaneously measures time and accuracy, suggested that slower time by minority elders was not related to a measurable effort to achieve greater accuracy. The frequency of commission errors was greater in our sample than in previous reports, especially among ethnic minority elders. Although significant differences were observed between the ethnic groups when matched for years of education, equating for literacy level eliminated all performance differences between African Americans and Whites on both cancellation tasks. 相似文献
9.
Quality assurance in the reproductive biology laboratory. 总被引:2,自引:0,他引:2
W Byrd 《Archives of pathology & laboratory medicine》1992,116(4):418-422
The goal of the clinical laboratory is to produce analytical results that are free of errors and useful in the diagnoses of patients' conditions and in the treatment of patients. Every laboratory assay contains a certain amount of errors. This can be due to random error, which is unpredictable, or to systematic error, which is the result of the difference between the control analysis and the expected target value. The purpose of a good quality assurance-quality control program is to detect errors when they become clinically significant and to ensure that all laboratory procedures, including analytical procedures, are designed to deliver as good a test result as possible. Reproductive biology laboratories that deal in human in vitro fertilization or andrology will have to develop quality assurance-quality control programs, much like those of anatomical pathology laboratories, due to the unique type of services that they offer. 相似文献
10.
M. C. Miller R. C. Byrd N. Ensslin W. C. Feldman M. S. Krick T. H. Prettyman P. A. Russo 《Applied radiation and isotopes》1997,48(10-12)
Monte Carlo simulations were carried out to simulate the response of a boron-loaded plastic scintillator array. These detectors offer potential advantages compared to moderated 3He systems because of their fast response and high efficiency. Tallies were made of neutron capture probability as a function of time and the results were coupled to assay variance estimates to evaluate detector performance. Orders-of-magnitude reductions in count time relative to a 50% efficient thermal counter are possible, in principle, for high (α,n) samples. 相似文献