Flavor preference conditioning by oral self-administration of ethanol

 Oral self-administration and operant tasks have been used successfully to confirm ethanol′s positive reinforcing effects in rats. However, in flavor conditioning tasks, ethanol is typically found to have aversive effects. The present studies explored this apparent paradox by examining the change in value of a flavor paired with orally self-administered ethanol in two different limited-access procedures. Rats were food-deprived and trained to drink (experiment 1) or to barpress for (experiment 2) 10% (v/v) ethanol during daily 30-min sessions using prandial initiation techniques. All rats were then exposed to a differential flavor conditioning procedure in which banana or almond extract was added to the drinking solution. One flavor (counterbalanced) was always mixed with ethanol (CS+), whereas the other flavor was mixed with water (CS–). By the end of conditioning, rats in both experiments drank more flavored ethanol than flavored water, confirming ethanol’s efficacy as a reinforcer. Moreover, barpress rates for CS+ exceeded those for CS– in the operant task. Ethanol doses self-administered in final sessions averaged about 1 g/kg. The effect of the flavor-ethanol contingency was assessed in preference tests that offered a choice between the two flavor solutions without ethanol. In both experiments, subjects developed a preference for the flavor that had been paired with ethanol. Thus, the outcome of flavor conditioning was consistent with that of the oral self-administration tasks in providing evidence of ethanol’s rewarding effects. These experiments confirm and extend previous studies showing that flavor aversion is not the inevitable result of flavor-ethanol association in rats. It seems likely that ethanol’s nutrient and pharmacological effects both contributed to the development of conditioned flavor preference. Received: 15 February 1997 / Final version: 11 June 1997     

西宁地区幼儿园儿童的膳食调查报告

本文对西宁地区幼儿园儿童进行了膳食调查。了解该人群的营养素摄入情况以及热能、蛋白质、脂肪来源分布和三大营养素供热比。同时提出所存在问题。     

Super-reactivity to amphetamine toxicity induced by schedule of reinforcement

The chronic exposure of rats to a schedule of operant water reinforcement coupled with chronically restricted access to water sensitized the animals to intermittentd-amphetamine injections (0.31–2.5 mg/kg with intervals of 12–23 days between any two injections) in such a way that this drug came to produce catastrophic losses of body weight (32.4% of control levels). In the sessions whend-amphetamine was administered, the rats were also given a total of 12 brief electric shocks. Loss of body weight was unaccompanied by parallel changes in operant behavior performance, or in food or water intake. Remarkably, in other studies with the same interventions (sham schedule sessions, water deprivation, and foot shocks), with the exception that reinforcers were never delivered,d-amphetamine did not produce catastrophic falls in body weight. This super-reactivity tod-amphetamine toxicity may be mediated by a possible stressor action of the schedule of reinforcement. Its mechanism might be analogous to the known sensitization produced by classical experimental stressor stimuli to the repeated administration ofd-amphetamine.     

Body composition in the elderly: Total body water and anthropometry

Body composition measured with isotopic dilution was compared with anthropometric measurements. The study was carried out in 47 subjects from both sexes, 65 to 92 years old. Total body water (TBW), anthropometric measurements, and dynamometry were assessed. TBW was significatively higher in men than women and decreased with age. Dynamometry and fatfree mass were well correlated (r=0.73 in males and r=0.58 in females) and significantly different between sexes. A negative correlation was found for dynamometry with age, being significant for women. Linear regression equations to predict TBW from anthropometric measurements in males and females were obtained: Males: TBW(I)=19.349+0.617 weight(kg) — 0.931 mid-arm circumference(cm)+0.122 dynamometry (kg) Females: TBW(l)=−5.531+0.343 weight(kg)-0.213 triceps skinfold (mm)+ 0.148 dynamometry(kg) + 3.424 wrist diameter (cm). This simple model is proposed for use in epidemiological and field studies where other more sophisticated methods can not be applied.     

术中输注氨基酸对硬膜外阻滞复合全麻开胸手术患者围术期体温的影响

目的评价术中输注氨基酸对硬膜外阻滞复合全麻食管癌和贲门癌手术患者围术期深部体温和代谢的影响。方法择期食管癌和贲门癌手术患者21例,ASAⅠ或Ⅱ级,随机分为3组(n =7):从麻醉诱导开始至手术结束,分别静脉输注氨基酸混合液240kJ·h-1(AA组)、等容量乳酸钠林格氏液(LR组)、葡萄糖溶液240kJ·h-1(GLU组)。麻醉诱导前至术后2h每5分钟测定鼓膜温度,于麻醉诱导前即刻、手术开始后1h和术后1h检测指尖血糖,采用4分表法评价术后2h内寒战的发生情况,采用间接测热仪测定术前与术后氧耗。结果与麻醉诱导前即刻比较,术后30min LR组和GLU组氧耗降低,AA组氧耗升高(P<0.01),术后2h LR组、GLU组鼓膜温度降低(P<0.05),AA组差异无统计学意义(P>0.05);与LR组和GLU组比较,AA组术后2h内寒战发生例数减少(P< 0.05),术后30min氧耗增多(P<0.05),LR组与GLU组比较差异无统计学意义(P>0.05)。结论硬膜外阻滞复合全麻开胸手术患者术中静脉输注氨基酸可通过提高基础代谢率,缓解围术期深部体温降低,减少术后寒战发生,而输注葡萄糖不产生此效应。     

“津血同源”“肾为唾”的研究

以23例肾功能不全与20例肾功正常患者的唾液尿素氮、钠、钾、舌面pH值和血液的相应生化检查作对照。结果唾液尿素氮、钾与血尿素氮、钾成正相关性。证实了中医“津血同源”“肾为唾”的理论。     

胰腺癌病人肠道通透性改变及其与机体组成的关系

目的:观察胰腺癌病人肠道通透性与机体组成的改变,并初步探讨两者间的关系.方法:以前瞻、随机和对照的方法,选取确诊胰腺癌首次入院的病人及健康志愿者各15例,作为试验组和对照组,测定尿乳果糖/甘露醇(L/M)比值、血清肿瘤坏死因子-α(TNF-α)和机体组成成分,并对试验组的肠道通透性L/M比值与血清TNF-α水平、机体组成之间的相关性进行分析.结果:①试验组尿L/M比值为0.331±0.343显著高于对照组0.129±0.136(P《0.05);血清TNF-α水平显著高于对照组(P《0.05).②试验组肌肉群重量显著低于对照组(P《0.05)、蛋白质重量极显著低于对照组(P《0.01)、而脂肪、水分、无机盐重量略轻于对照组,两组间差异无显著性意义.③试验组尿L/M比值与血清TNF-α水平呈极显著性正相关(P《0.01);尿L/M比值与蛋白质、脂肪呈极显著性负相关(P《0.01),与水分呈极显著性正相关(P《0.01);而试验组血清TNF-α浓度与蛋白质、脂肪呈极显著性负相关(P《0.01)、与水分呈极显著性正相关(P《0.01).结论:胰腺癌病人肠道的通透性增加,机体组成有显著改变,两者间密切相关.这可能与血清TNF-α水平的升高有关.     

5～14岁男性体格发育水平与性器官发育关系的研究

目的：探讨男性青少年体格发育水平与性器官发育关系。方法：收集4854例5—14岁男性青少年的身高、体重并计算出体质指数，测量阴茎的长度、周长和睾丸的纵径、横径，观察二者之间的关系。结果与结论：身高与阴茎的长度、周长和睾丸的纵径均呈二次方程曲线关联，而与睾丸横径无明显关联。体重和体质指数与阴茎有长度、周长和睾丸的纵径、横径无明显关联。     

赤鳞鱼脂肪酸组分分析及营养价值的初步评定

赤鳞鱼脂肪酸组分分析及营养价值的初步评定李全阳，岳永生，张庆朝（山东农业大学牧医系，泰安２７１０１８）ＦａｔｔｙＡｃｉｄｓＣｏｍｐｏｓｉｔｉｏｎａｎｄＮｕｒｉｔｉｏｎａｌＥｖａｌｕａｔｉｏｎｏｆｔｈｅＣｈｉ一ＬｉｎＦｉｓｈ￥ＬｉＱｕａｎｙａｎｇ；Ｙｕ...     

不同针刺手法调节体温效应机制研究概况

目的:介绍近年不同的针刺手法对体表温度调节效应的研究,并探讨其产生体温效应的机制。方法:从临床研究、实验研究等方面进行综述。结论:针刺穴位的作用及其疗效,随着手法引起的温度变化而不同,针刺补法引起体温升高,而泻法则引起体温下降。体表温度是由血液循环状态、交感神经兴奋程度和组织新陈代谢状态等多方面决定的,不同的针刺手法引起的皮肤温度变化与影响上述3个环节状态有关。