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61.
Two experiments were conducted to assess the effects of chronic subcutaneous injections of morphine (1.0 mg/kg) or saline on the pattern and amount of sweetened ethanol and water intake in fluid restricted Long-Evans rats. Following daily injections, 2-h two-bottle choice tests were conducted with water and an ethanol solution (15% ethanol v/v in 5% sucrose w/v). During a 20-day acquisition phase (Experiment 1), ethanol intake patterns and amounts did not differ between saline (n = 6) and morphine (n = 6) groups. Both groups exhibited ethanol intake patterns that decreased exponentially throughout the session suggesting control by fluid restriction procedures. Morphine decreased water intake during initial periods of each session and increased intake during later periods. In Experiment 2, morphine and saline injections were reversed across three phases with the same rats. Morphine increased total ethanol consumption during the first few days of each 15-day phase, but the groups did not differ thereafter, and the initial increases produced no statistically significant group differences. Additionally, morphine augmented ethanol intake in early portions of sessions, while water intake was decreased and increased during early and later portions of each session, respectively. Analysis of the data from the last 5 days of each phase indicated that, when injected with morphine, the group which received saline during acquisition consumed significantly more ethanol solution than the group injected with morphine during acquisition. The effect on patterns of water and ethanol intake were observed, regardless of the drug injected during acquisition.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Brachytherapy by embolization with radiotherapeutic microspheres following intraarterial infusion of a radiosensitizer represents an attempt to combine several selective modalities into a more potent, focused attack on regionally confined tumors. In pursuit of this goal, we examined the ability of foxhounds with surgically implanted hepatic arterial (HA) delivery systems to tolerate a clinically relevant dosage of HA yttrium-90 (Y-90) by microsphere administration either alone or preceded by a 28-day constant HA infusion of either 5-bromo-2'-deoxyuridine (BUDR) or a control solution. Five dogs received BUDR (10 mg/kg/day) and five a control buffer infusion for 28 days immediately prior to the administration of Y-90-coated 15 micron resin microspheres (equivalent of 5000 rads to the entire liver) to each dog on day 31. In all animals, blood counts, bilirubin, amylase, appetite, weight, and behavior remained unchanged. Dogs receiving the microspheres after buffer infusion alone exhibited no hepatic enzyme alanine aminotransferase or alkaline phosphatase elevation. Alanine aminotransferase and alkaline phosphatase levels both rose during the third week of BUDR infusion, and while subsequent microsphere administration further increased enzyme levels, these levels had largely normalized by necropsy on day 82. At necropsy, the type and degree of hepatic toxicity among the animals receiving radioactive microspheres was comparable to that previously described in patients receiving external beam hepatic irradiation at conventional doses (2000-3000 rads). Also noted was a radiation-induced cholecystitis (due in large part to the gallbladder's total reliance on the hepatic artery for blood supply). One resin microsphere dog exhibited a small quantity of microspheres in the lungs causing focal radiation-induced granulomas suggesting the need to assess shunting of microspheres through the liver in clinical studies. Thus, HA Y-90 microspheres with BUDR can produce acceptable, nonlethal, and tolerable toxicities in this dog model suggesting that clinical studies of this combination are not likely to be contraindicated by synergistic toxicity. Although HA BUDR did not contribute significantly to the toxicity of the Y-90 microspheres, HA BUDR by itself administered uninterrupted for 4 weeks may, like HA FUDR (clinically), cause chemical hepatitis/cholangitis. The unexpected fragmentation of the resin spheres (albeit without myelosuppression) has led us to begin studies with a recently developed nondisruptible glass microsphere (ThereSphere) in which the Y-90 is part of the glass matrix and cannot leach.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
64.
Forty depressed patients and 36 age- and sex-matched controls were given 250 μg ACTH1–24 by bolus. Plasma steroid hormone levels were measured prior to and 60 min after ACTH administration. The depressed patients had significantly greater cortisol (F), 11-deoxycortisol (S), androstenedione (AD), and 17-hydroxyprogesterone (17-OHP) responses (delta; p<0.05) and a marginally greater 11β-hydroxyandrostenedione (11β-OHAD) response (delta; p=0.091) than the controls. There was no significant difference in the corticosterone (B) response between the two groups.

With the exception of 11β-OHAD, all the steroid hormones were significantly negatively correlated with age in the controls, but only S and AD marginally demonstrated this relationship in the depressed patients. F, S, AD, 17-OHP, and B, but not 11β-OHAD, were significantly positively correlated with each other in the controls, but only F was significantly correlated with AD in the depressed patients. These data suggest that the hypercortisolemia found in some depressed patients involves increased precursor and metabolite levels both at baseline and in response to exogenous ACTH, compared to controls. Furthermore, variability in these precursors is greater in depressed patients, and their relationship to age is lost. These findings are consistent with the hypothesis that adrenal products other than cortisol also could be related to affective symptoms.  相似文献   

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Computed tomographic (CT) scans are performed on virtually all patients with severe head injury at the time of admission. Because of the time involved in obtaining these studies, the evacuation of significant intracranial mass lesions is delayed. To avoid such delays, the authors performed burr-hole exploration for the diagnosis of intracranial hematomas before CT scans were obtained in 100 consecutive head-injured patients with clinical signs of tentorial herniation or upper brain stem dysfunction upon admission to the emergency room. Patients in whom a hematoma was discovered had a craniotomy for evacuation of the clot; those in whom the exploration was negative had a CT brain scan immediately after operation. Burr-hole exploration revealed extracerebral mass lesions in 56 patients. In 38 patients, the exploration was negative, and postoperative CT scanning showed no significant hematoma. Of 6 patients in whom the CT scan demonstrated extraaxial hematomas requiring surgical evacuation, 4 had subdural hematomas that were missed because the exploration was incomplete; 1 patient had an epidural hematoma and 1 had a subdural hematoma contralateral to a craniotomy on the side of a positive initial burr-hole exploration. Our results indicate that the relatively small subgroup of head-injured patients with early tentorial herniation or upper brain stem compression have a high incidence of immediate extraaxial hematomas and a low incidence of intracerebral hematomas. This is particularly true of patients over 30 years of age and those who suffer low speed trauma, such as falls and vehicle-pedestrian accidents.  相似文献   
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Ten male volunteers received a 1-min i.v. infusion of a new water soluble steroid anaesthetic agent, ORG 21465. Individuals received doses ranging from 0.8 to 1.8 mg kg-1. All subjects experienced venous pain at the site of injection; those receiving 1.0 mg kg-1 or more became anaesthetized. There was no evidence of histamine release and apnoea did not occur. Excitatory phenomena were observed in all subjects and were dose related; no spikes were seen on the EEG. Pharmacokinetic analysis supported a three-compartment (non-weight- related) model with compartmental volumes V1, V2 and V3 of 4.31, 14.2 and 89.4 litre, respectively. Clearance from the central compartment V1 was 1.55 litre min-1. Inter-compartmental clearances Q1 and Q2 were 2.54 and 1.79 litre min-1. We found that ORG 21465 was an effective anaesthetic in humans. The relationship between sedation, anaesthesia and excitation requires further exploration.   相似文献   
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