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1.
Effects of chemicals on delayed matching behavior in pigeons I: acute effects of drugs 总被引:3,自引:0,他引:3
D E McMillan 《Neurotoxicology》1981,2(3):485-498
Pigeons were trained to peck a red or green center key 15 times to turn it off. After a delay, two side keys, one red and one green were illuminated. Pecks on the side key whose color matched the color that the center key had been produced food. Pecks on the other side key produced a timeout. The effects of various drugs were studied as the delay between extinguishing of the center key light and illumination of side keys was varied from 1 to 8 sec. Pentobarbital and phencyclidine consistently decreased matching, but morphine, d-amphetamine and delta 9-tetrahydrocannabinol had little effect on matching even at doses that increased latency to respond and decreased the rate of responding. Pentobarbital frequently decreased matching at doses below those that increased response latency and decreased response rate, but phencyclidine decreased matching only at doses that increased latencies and decreased rates. The effects of pentobarbital on matching did not depend on the delay duration. 相似文献
2.
D P Taggart D C McMillan T Preston R Richardson A Shenkin H J Burns D J Wheatley 《Nutrition (Burbank, Los Angeles County, Calif.)》1991,7(4):271-274
Total energy expenditure (TEE) was measured by doubly labeled water in 13 preoperative patients undergoing elective coronary artery surgery and compared to resting energy expenditure (REE) measured by indirect calorimetry (IC) calculated from the Harris-Benedict (HB) formula or from formulas based on midarm circumference and arm muscle circumference. Mean REE measured by IC and calculated from the HB, midarm circumference, arm muscle circumference formulas were 62, 75, 62, and 69%, respectively, of TEE measured by doubly labeled water. REE measured by IC correlated significantly with that predicted by the HB (p = 0.006) but not the anthropometric formulas. The relationship between REE derived from anthropometric predictive formulas and REE measured by IC is altered in ischemic heart disease. 相似文献
3.
K. KARNICKI† R. D. MCBANE II † R. S. MILLER† R. J. Leadley JR ¶ J. MORSER W. G. OWEN†‡ J. H. CHESEBRO§ 《Journal of thrombosis and haemostasis》2004,2(12):2162-2169
BACKGROUND/OBJECTIVE: The efficacy of a direct factor (F)Xa inhibitor, ZK-807834, was compared with indirect inhibition by enoxaparin for inhibition and deaggregation of acute platelet-rich thrombi in a well-characterized porcine carotid injury model. METHODS: A crush injury was performed on a randomly chosen carotid artery and the thrombus allowed to propagate for 30 min. Pigs then received intravenous drug for 35 min: ZK-807834-Dose 1 (40 microg kg(-1) bolus + 1.5 microg kg(-1) min(-1) infusion, n=6); ZK-807834-Dose 2 (20 microg kg(-1) bolus + 0.75 microg kg(-1) min(-1) infusion; n=6); enoxaparin (1 mg kg(-1) bolus; n=6); or saline (n=6). Five minutes after drug initiation, the contralateral artery was injured. Thrombus size was monitored by scintillation detection of autologous 111In-platelets. RESULTS: The prothrombin time ratio was 2.2 +/- 0.1; 1.4 +/- 0.3; 1.2 +/- 0.9 and 1.1 +/- 0.2, respectively. ZK-807834-Dose 1 significantly inhibited carotid platelet deposition (525 +/- 226 x 10(6) cm(-2); P = 0.008), whereas ZK-807834-Dose 2 (2325 +/- 768) and enoxaparin (1236 +/- 383) were not different from saline (2776 +/- 642). Thrombus deaggregation was greatest for animals receiving ZK-807834-Dose 1 (473 +/- 185). Neither ZK-807834-Dose 2 (1588 +/- 480) nor enoxaparin (1618 +/- 686) was different from saline control (2222 +/- 598). CONCLUSIONS: Direct FXa inhibition with ZK-807834, at a prothrombin time ratio of 2.2, effectively inhibits thrombosis and promptly deaggregates thrombi induced by arterial injury. In contrast, indirect FXa inhibition with enoxaparin was ineffective. 相似文献
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Dean McMillan Richard P. Hastings Jon Coldwell 《Journal of Applied Research in Intellectual Disabilities》2004,17(4):255-265
Background There is a high rate of physical violence in populations with intellectual disabilities, and this has been linked to problems for the victim, the assailant, members of staff and services. Despite the clinical significance of this behaviour, few studies have assessed methods of predicting its occurrence. The present study examined clinical and actuarial methods of predicting violence in a forensic intellectual disability hospital. Methods The sample for the study consisted of people resident in the hospital during a 1‐year period (n = 124). Clinical prediction used a risk rating made by members of the person's clinical team, whereas actuarial prediction used the number of violent incidents in the 6‐months before the date of the clinical risk assessment. Computerized hospital records of violence in the 6 months after the assessment were used to examine the predictive accuracy of the two methods. Results The clinical method produced an area under the curve of 0.74 (95% CI: 0.65–0.83) in a receiver–operating characteristic curve analysis. The value for the actuarial method was 0.77 (95% CI: 0.69–0.86). Both methods performed at levels significantly above chance, but no one method was found to be superior to the other. Conclusions These findings suggest that it is possible to predict who is at risk of violence in forensic populations with intellectual disabilities. Here, the authors discuss the clinical implications of these findings and the clinical application of risk prediction within clinical services. 相似文献
8.
SOLOMON HOWARD M.; FERENZ RAYANNE L.; KENNEDY GERALD L. JR.; STAPLES ROBERT E. 《Toxicological sciences》1991,16(3):414-422
Developmental Toxicity of Dimethylacetamide by Inhalation inthe Rat. SOLOMON, H. M., FERENZ, R. L., KENNEDY, G. L., ANDSTAPLES, R. E. (1991). Fundam. Appl. Toxicol. 16, 414422.Dimethylacetamide (DMAC) is a widely used industrial solvent.It has been reported to be teratogenic when given to rats byinjection or following dermal application. Most of these studiesemployed large single doses and did not examine both the fetaland the maternal response. In this study, groups of pregnantCrl:CD rats were exposed to 32, 100, or 282 ppm DMAC by inhalationfor 6 hr/day from Days 6 through 15 of gestation (day on whichcopulation plug was detected was termed Day 1G). A control groupof chambered pregnant rats was exposed simultaneously to aironly. All female rats were euthanized on Day 21G. At 282 ppm,both maternal weight gain during the exposure period and fetalweight were significantly decreased and accompanied by a significantdose-response trend. These effects were not seen in rats inhalingeither 32 or 100 ppm. Fetal resorptions were not increased inany of the groups exposed to DMAC. Fetal incidences of external,visceral, or skeletal variations and malformations were similarbetween the test and control groups. Therefore, both fetal andmaternal toxicity were noted at 282 ppm and the no-observedadverse-effect level under these experimental conditions was100 ppm for both the dam and the conceptus. DMAC was not demonstratedto produce malformations in the rat fetus even at a level thatwas toxic to the dam. 相似文献
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10.
R G Watson S A McMillan W Dickey J D Biggart K G Porter 《The Quarterly journal of medicine》1992,84(305):713-718
Eighteen patients with a variety of non-gastrointestinal symptoms were incidentally found to have circulating antireticulin antibody and on subsequent testing were also positive for antigliadin antibody. They prospectively underwent jejunal biopsy to determine whether or not they had coeliac disease. Their age range was 21-79 years (mean 42 years). Enteropathy was present in 13 (72 per cent) and was always associated with circulating IgA antigliadin antibody. Enteropathy was not present in the five cases who had only IgG antibody. Clinical improvement occurred in eight of 11 patients who complied with a gluten-free diet and was paralleled by an improvement in the mucosal histology in seven of eight who were re-biopsied. The most remarkable cases were two patients who presented with severe debility and no apparent haematological or biochemical abnormalities, and who subsequently made a dramatic recovery on a gluten-free diet. It is concluded that antireticulin antibody detected by routine autoantibody screening and confirmed to have IgA antigliadin antibody specificity is a useful indicator of an otherwise undiagnosed enteropathy. This serves to emphasize that the condition can sometimes be associated with atypical features and significant morbidity. 相似文献