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61.
Morphine place conditioning is differentially affected by CCKA and CCKB receptor antagonists. 总被引:2,自引:0,他引:2
In the present study we have examined the interaction between the selective cholecystokinin (CCK)A and CCKB receptor antagonists, devazepide and L365-260 on morphine conditioned place preference (CPP). Using an unbiased procedure, morphine (1.5 mg/kg) produced a reliable CPP which was observed irrespective of the conditioning compartment type. Pretreatment with devazepide (0.001-0.01 mg/kg s.c.) produced a dose related attenuation of this response. At higher doses (0.1-1 mg/kg) this antagonism became variable and dependent on the training compartment with blockade only observed when conditioning was to the white/rough textured environment. This profile has also been reported for the serotonin (5-HT)3 receptor antagonist ondansetron. The CCKB antagonist L365-260 (0.000001-0.01 mg/kg) failed to antagonize the morphine CPP, if anything a mild potentiation was observed. To study this further we examined the interaction between L365-260 (0.01 mg/kg) and a subthreshold dose of morphine (0.3 mg/kg). At these doses neither drug elicited CPP, however when co-administered a significant CPP was recorded. Finally, L365-260 at 1 mg/kg induced a mild but significant CPP when administered alone. These results suggest a differential role of CCK receptor subtypes on reward-related behaviour and complement previous studies suggesting bimodal effects of CCK systems on mesolimbic dopamine function. 相似文献
62.
D Nguyen I Abdul-Rasool D Ward J Hsieh D Kobayashi S Hadlock F Singer B Bloor 《Anesthesiology》1992,76(4):573-579
Dexmedetomidine (DMED) is a novel alpha 2 adrenergic agonist that has been shown to have potent analgesic and anesthetic sparing effects. This study was designed to investigate the effects of DMED, both alone and combined with isoflurane, on resting ventilation, the hypercapnic response, and the hypoxic response in dogs. When given alone, 1 microgram/kg decreased resting ventilation by 22% but at larger doses (10, 20, and 100 micrograms/kg) resting ventilation increased, doubling at 100 micrograms/kg. Doses of 10 micrograms/kg and greater caused a maximum depression of 60% in the slope of the hypercapnic response, but no dose had a significant effect on the hypoxic ventilatory response. A dose of 3 micrograms/kg of DMED reduced isoflurane MAC from 1.3% to 0.37%, and the ventilatory effects of this 1 MAC combination were intermediate between the awake values and those of isoflurane-anesthetized (1.3%) dogs. Atipamezole is a specific centrally acting alpha 2 receptor antagonist and when given with DMED in isoflurane-anesthetized dogs prevented the ventilatory depression. However, atipamezole alone also ventilatory stimulating effects, which may indicate tonic alpha 2 adrenergic activity. The ventilatory depression caused by DMED, either alone or combined with isoflurane, at doses that significantly reduce anesthetic requirements are relatively mild. 相似文献
63.
64.
Direct effect of VX and soman on nicotinic receptors 总被引:1,自引:0,他引:1
65.
本文观察了52侧(男46,女6)成人尸体臀上动、静脉深上支进入髂嵴情况.臀上动、静脉深上支分为前、中、后支;本文测量了臀上动、静脉深上支的外径及各分支进入髂嵴的距离.臀上动、静脉深上支的分支在髂嵴前部及中部分布较多,前支的分支为3~8支,其中以4~6支者为多见,占78.8±5.5%;中支的分支1~4支,其中以2~3者为多见,占73.1±6.1%.因此,臀上动脉深上支作为游离髂骨移植术取髂嵴的前部和中部较宜. 相似文献
66.
Marenne P Budde Titia E De Lange Gus A Dekker Annabelle Chan Anh-Minh T Nguyen 《The journal of maternal-fetal & neonatal medicine》2007,20(9):687-693
OBJECTIVE: This study was undertaken in order to determine the risk factors for pregnancies complicated by placental abruption in a socio-economically disadvantaged region in metropolitan Adelaide. METHODS: This was a retrospective case-control study including all singleton pregnancies resulting in placental abruption between 2001 and 2005. RESULTS: The overall incidence of placental abruption was 1.0%; the overall perinatal mortality among the births with abruption was 13%. Univariate analyses showed the following significant risk factors for placental abruption: preterm pre-labor rupture of the membranes (PRE-PROM; odds ratio (OR) 4.79, 95% confidence interval (CI) 1.52-15.08), non-compliance with antenatal care (OR 2.93, 95% CI 1.06-8.90), severe intrauterine growth restriction (IUGR), and elevated homocysteine levels (OR 45.55, 95% CI 7.05-458.93). Severe IUGR was significantly more common in the abruption group compared with the control group (p = 0.032). In the multivariate analysis, PRE-PROM remained a significant independent risk factor for placental abruption. Marijuana use, domestic violence, and mental health problems were more common (borderline significance) in the abruption group. Smoking and preeclampsia were not found to be associated with placental abruption in this study. CONCLUSIONS: In this high-risk population, PRE-PROM and elevated homocysteine levels appear to represent the major risk factors for placental abruption. 相似文献
67.
68.
An autopsy case of disseminated HSV type 2 infection occurring in a neonate at 32 weeks' gestation, delivered by cesarean section after premature rupture of membrane of 7 days duration, is presented. Herpes simplex virus type 2 was isolated from the vesicular skin lesion. The mother and patient had specific antibody to type 2 herpes simplex virus. Patient's parents had denied any herpetic orolabial or genital lesion during or before this pregnancy. Cultures from the cervical and vaginal swabs of the mother were negative for HSV. Postmortem examination showed hepatic necrosis, skin vesicle, devastating necrotizing inflammation of the brain, chorioretinitis and interstitial pneumonitis. 相似文献
69.
Because of the rising percentage of elderly in the population and the cost of health care expenditures, interest has increased in preventive health care services for the aging. Although the effectiveness of such programs is still being discussed by policy makers, the number of preventive health programs for the elderly is increasing. One of the oldest and largest preventive health programs for the elderly in the United States, the California Preventive Health Care for the Aging Program (PHCAP) is analyzed. The typical PHCAP participant was white, female, between 70 and 79 years of age, and living in an urban area. More than half (59 percent) of the PHCAP participants had some kind of private medical insurance in addition to Medicare coverage. Seventy-seven percent of the participants had seen a physician within the previous year. The most frequently reported chronic conditions were arthritis (31 percent), hypertension (24 percent), cardiovascular problems (13 percent), and vision and hearing problems (18 and 11 percent). Twenty-seven percent of the population were hypertensive; 7 percent of these had moderate to severe hypertension. Eighty percent of the participants were identified as having at least one problem; 40 percent were referred to a physician. Frequently, public health programs need to be evaluated without the benefit of a controlled trial design. This analysis of a statewide preventive health care program for the aging, PHCAP, shows the program's effectiveness in detecting a large number of health problems and making extensive referrals to other health professionals, particularly physicians. These findings should be useful to health practitioners and policy makers developing similar statewide programs for the elderly. 相似文献
70.
J W Ellingboe W Spinelli M W Winkley T T Nguyen R W Parsons I F Moubarak J M Kitzen D Von Engen J F Bagli 《Journal of medicinal chemistry》1992,35(4):705-716
The synthesis and Class III antiarrhythmic activity of a series of 4-[(methylsulfonyl)amino]benzamides and sulfonamides are described. Selected compounds show a potent Class III activity and are devoid of effects on conduction both in vitro (dog Purkinje fibers) and in vivo (anesthetized dogs). Compounds having a 2-aminobenzimidazole group were found to be the most potent, and one compound having this heterocycle (5, WAY-123,398) was selected for further characterization. Compound 5 was shown to have good oral bioavailability and a favorable hemodynamic profile to produce a 3-fold increase of the ventricular fibrillation threshold and to terminate ventricular fibrillation, restoring sinus rhythm in anesthetized dogs. Voltage-clamp studies in isolated myocytes show that 5 is a potent and specific blocker of the delayed rectifier potassium current (IK) at concentrations that cause significant prolongation of action potential duration. 相似文献