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101.
Antagonist properties of d-LSD at 5-hydroxytryptamine2 receptors 总被引:1,自引:0,他引:1
The hallucinogenic agent d-lysergic acid diethylamide (d-LSD) interacts with a number of serotonin (5-hydroxytryptamine [5-HT]) receptor subtypes in the central nervous system. It has been hypothesized that hallucinosis is produced by agonist activity at 5-HT2 receptors. There exist, however, numerous data from radioligand binding, cellular, smooth muscle, and behavioral studies that suggest that d-LSD is a potent 5-HT2 antagonist. These data are reviewed in this report. In addition, d-LSD displays agonist activity at 5-HT1A and 5-HT1C receptor subtypes, as determined in biochemical studies. At the present time, agonist interactions at 5-HT1C receptors, as opposed to 5-HT2 receptors, appears to be a more likely "common mechanism of action" of hallucinogenic agents. 相似文献
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Kapp Judith A.; Pierce Carl W.; Webb David R.; Devens Bruce; Godfrey Wayne; Fukuse Satoshi; Engleman Edgar; Lake Jeffrey P.; Magnani John I.; Maiti Pradip K.; Sehon Alec 《International immunology》1995,7(8):1319-1330
Although reliable antibodies are available that distinguishhuman suppressor T (Ts) cells from CTL and other T cells, feware available for murine Ts cells. We have developed a mAb (984D4.6.5)that, in the presence of complement, depletes alloantigen-specificTs cells but not CTL. This antibody recognizes activated TTscells but not their precursors. In these studies, flow cytometricanalysis demonstrates that 984D4.6.5 reacts with several Tscell hybridomas, cloned Th cell lines and WEHI-3 (a myelomonocytictumor cell line). Reactivity was not detected with BW5147, Thcell hybridomas, cloned Th cells, CTL lines and hybridomas,B cell lines, thymocytes, splenocytes, bone marrow cells nora variety of tumor cells. Among 984D4.6.5 positive lines, expressionis heterogeneous and the number of cells expressing high levelsof the epitope is increased when the hybridomas are maintainedat a relatively high cell density. Neuriminidase and pronasedeplete the epitope recognized by mAb 984D4.6.5. Protein synthesisand glycosylation inhibitors also reduce expression of thisepitope. These observations suggest that the epitope recognizedby 984D4.6.5 is a carbohydrate linked to a polypeptide. Thisantibody was tested by ELISA for binding to a large panel ofcarbohydrates and glycollpids coupled to BSA. The only one thatbound 984D4.6.5 was LS tetrasaccharide c (NeuNAc2-6Galpß1-4GIcNAcß1-3GaIß1-4Glc),an O-linked carbohydrate. Comparative analysis shows that boththe sequence and the linkage of these sugars are essential tothe reactivity with the 984D4.6.5 antibody. This epitope isexpressed by a glycoprotein of-200 kDa, as shown by Westernblots. The identity of this glycoprotein remains to be determined,but indirect evidence suggests that it is not CD45. 相似文献
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105.
Pierce C 《Health data management》1995,3(10):70-2, 74
106.
Pierce C 《Health data management》1995,3(8):65-6, 69-70
A growing number of the nation's 67 Blue Cross and Blue Shield plans, many of which are dominant health insurers in their markets, are attempting to expand their electronic health care transactions business. At least a dozen plans have created claims clearinghouses designed to handle claims and other electronic transactions destined for any payer. 相似文献
107.
Effects of in-season (5 weeks) creatine and pyruvate supplementation on anaerobic performance and body composition in American football players. 总被引:4,自引:0,他引:4
M H Stone K Sanborn L L Smith H S O'Bryant T Hoke A C Utter R L Johnson R Boros J Hruby K C Pierce M E Stone B Garner 《International journal of sport nutrition》1999,9(2):146-165
The purpose of this investigation was to study the efficacy of two dietary supplements on measures of body mass, body composition, and performance in 42 American football players. Group CM (n = 9) received creatine monohydrate, Group P (n = 11) received calcium pyruvate, Group COM (n = 11) received a combination of calcium pyruvate (60%) and creatine (40%), and Group PL received a placebo. Tests were performed before (T1) and after (T2) the 50 week supplementation period, during which the subjects continued their normal training schedules. Compared to P and PL, CM and COM showed significantly greater increases for body mass, lean body mass, 1 repetition maximum (RM) bench press, combined 1 RM squat and bench press, and static vertical jump (SVJ) power output. Peak rate of force development for SVJ was significantly greater for CM compared to P and PL. Creatine and the combination supplement enhanced training adaptations associated with body mass/composition, maximum strength, and SVJ; however, pyruvate supplementation alone was ineffective. 相似文献
108.
McEligot AJ Rock CL Flatt SW Newman V Faerber S Pierce JP 《The Journal of nutrition》1999,129(12):2258-2263
We investigated predictors of change in plasma carotenoids from baseline to 3 y and examined plasma carotenoid concentrations at 1 and 3 y in response to a high vegetable diet. Participants were 56 women diagnosed with breast cancer and enrolled in a randomized feasibility study for a trial examining the effect of a diet high in vegetables and fruits on the risk of breast cancer recurrence. Independent t test analysis revealed that the intervention group had significantly higher vegetable and fruit servings and fiber at 12 mo and significantly higher vegetable servings at 36 mo compared with the control group (P < 0.05). Energy intake from fat was significantly lower in the intervention group at 12 and 36 mo. The intervention group had significantly higher consumption of beta-carotene, alpha-carotene, lutein and beta-cryptoxanthin at 12 mo (P < 0.05). beta-Carotene, alpha-carotene and lutein intakes also were significantly higher at 36 mo (P < 0.05). At 36 mo, the intervention group had significantly higher plasma concentrations of alpha-carotene and beta-carotene compared with the control group. Repeated-measures ANOVA revealed that the intervention group had significantly increased (P < 0.05 with Bonferroni correction) plasma beta-carotene, alpha-carotene, lutein and lycopene concentrations at 12 and 36 mo compared with baseline. Baseline carotenoid concentrations were significantly inversely predictive (P < 0.05) of plasma carotenoid change. In addition, change in body mass index (BMI) and plasma cholesterol concentrations were predictive of plasma carotenoid change from baseline to 3 y. Results of this study demonstrate that change in plasma carotenoid concentrations is associated with change in BMI, change in plasma cholesterol and baseline carotenoid concentrations. Plasma carotenoid response can be an indicator of long-term high vegetable intake for women at risk of breast cancer recurrence. 相似文献
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110.
为探讨体外循环(CPB)导致心脏植物神经系统(CAS)损伤的机理,了解温血心停跳液能否防止CPB后心率变异性(HRV)的降低,采用对照方法观察了温血心停跳液与冷晶体心停跳液对狗HRV的影响。结果显示:CPB后温血心停跳液组(WB组)和冷晶体心停跳液组(CC组)的全频谱(TP)、低频(LF)和高频(HF)均较术前明显降低(P<0.05),而且CC组比WB组降低更明显(P<0.05),但LF/HF在组内及组间均无明显变化(P>0.05)。CPB后24小时平均心率(MHR)明显增加(P<0.05),且CC组高于WB组(P<0.05)。本研究表明:采用温血心停跳液或冷晶体心停跳液的CPB不会干扰CAS平衡,但均能使HRV降低,温血心停跳液不能防止HRV损害。 相似文献