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91.
Suchday S Carter MM Ewart CK Larkin KT Desiderato O 《Journal of behavioral medicine》2004,27(4):319-341
The current study describes the creation and validation of the Anger Cognitions Inventory (ACI) to assess the cognitive appraisals associated with resentful and reflective anger. The ACI was created based on a content analysis of self-reports of participants' thoughts and feelings following anger provocation in the laboratory. Exploratory and confirmatory factor analyses on two separate college student samples (N = 267 and N = 276, respectively) revealed five subscales which could validly be grouped into resentful and reflective anger. Convergent and divergent validity data showed that resentful anger correlated positively with anger-out/trait anger and reflective anger correlated positively with anger-in/brooding. A second study showed positive correlations between rumination and delayed cardiovascular recovery following anger provocation. Limitations of both studies include restricted samples which limit generalizability of results and cardiovascular recovery data collected in Study II which does not include assessment of autonomic balance between vagal and sympathetic responsivity. 相似文献
92.
The behavioral and neurochemical effects of striatal DA depletions were investigated in rats lesioned as weanlings (Day 27) or as adults (250-300 g). Administration of 6-OHDA into the medial forebrain bundle resulted in comparably large (> or = 95%) depletions of tissue levels of DA in both age groups. As expected, rats depleted of DA as adults exhibited marked deficits in motoric behavior and body weight regulation that persisted for the 8 days of postsurgical observation. In contrast, rats depleted of DA as weanlings were spared from such deficits, and their behavior closely resembled that of age-matched controls. Microdialysis studies revealed dialysate levels of striatal DA that paralleled these age-dependent behavioral differences. At a time when age-related behavioral differences were still quite pronounced (5-6 days postsurgery), basal DA levels were reduced by 80% of control values in rats lesioned as adults whereas basal DA levels in rats lesioned as weanlings were unchanged relative to their controls. Finally, adults depleted of striatal DA as weanlings were no more sensitive to the movement-impairing effects of intrastriatal sulpiride (3.0 or 10.0 micrograms/hemisphere) infusions than were control rats. These data suggest that weanlings compensate for large, but incomplete, denervation of striatal DA with markedly enhanced release and turnover from residual terminals. This developmental plasticity may prevent the occurrence of behavioral deficits soon after the lesion and also the supersensitivity to the challenging effects of DA antagonists as animals grow into adulthood. 相似文献
93.
Two experiments were designed to investigate the effect of below-zero habituation training on skin conductance response (SCR) amplitude to a change in auditory stimulus frequency. In both experiments, subjects were trained with a 1000 Hz tone until zero responding and then received 5, 10, or IS further training trials. In Experiment 1 (N=45), subjects then received 1 presentation of a test stimulus of 1400 Hz, while in Experiment 2 (N=45), the test stimulus was a tone of 670 Hz. On the basis of dual-process theory, it was hypothesized that response amplitude to the test stimulus would be inversely related to amount of below-zero training. However, the results of both experiments indicate that SCR amplitude was positively related to amount of below-zero training. These results suggest that in situations of extended habituation training, an expectancy or subjective probability of stimulus occurrence gradient is important in determining response amplitude to a test stimulus. 相似文献
94.
Helen J. Cooke John Atherton Young 《Pflügers Archiv : European journal of physiology》1970,318(4):315-324
Summary Techniques have been developed for collection of urine in embryonic and newly hatched chickens for the purpose of studying the development of renal function.The reliability of EDTA-51Cr as a substitute for inulin-14C in the determination of GFR was studied. Since inulin and EDTA-51Cr clearances in the hatched chicken averaged 1.61±0.23 (S.E.) ml/min per kg body weight and 1.58±0.27 ml/min per kg body weight, respectively, EDTA-51Cr clearance was considered a suitable measure of GFR.GFR increased significantly in the first few days after hatching. Filtration rate was 0.068±0.008 (S.E.) ml/min per g kidney weight in the embryo and increased to 0.148±0.008 ml/min per g shortly after hatching. By nine days after hatching GFR had risen to 0.290±0.015 ml/min per g, a value comparable to that reported for the adult.Clearances of sodium, potassium, chloride and total osmolyte also increased with age. When these clearances were corrected for changing glomerular filtration rates the embryonic chicks were found to excrete a greater percentage of the filtered load. These results show that adult levels of glomerulo-tubular balance are not attained until after hatching.A preliminary report of this work has already been published [3]. 相似文献
95.
Summary Lung function was studied double blind and randomized in 5 patients with mild asthma bronchiale and 10 normal adults before and 30, 60 and 90 minutes after one drop of 0.5% Timolol, 0.6% Metipranolol or 0.9% NaCl in each eye.In the asthmatics bronchoconstriction was seen after both -receptor blocking agents, more pronounced after Timolol than after Metripranolol. There was a decrease in the forced expiratory volume in one second (FEV1.0) of 32, respectively 18%. No changes were observed in the normal subjects.In a separate studie no significant changes were seen in the mean values of 10 other asthmatic subjects after 1% Pindolol, 3% Pilocarpin or 0.9% NaCl.However, in two patients FEV1.0 was reduced by 15% and 20% of the control values after applying Pindolol.In summary, not only -receptorblocking agents without ISA produce a bronchoconstriction in asthmatic subjects, but also -blocker with ISA in individual cases.
Abkürzungen FEV1.0 Ein-Sekunden-Wert - ISA intrinsische sympathikotone Aktivität - MEV maximaler exspiratorischer Fluß - Rtos oszillatorische Resistance Ein Teil der Daten wurde der Dissertationsschrift von Frau Janette Gehre entnommen. 相似文献
Abkürzungen FEV1.0 Ein-Sekunden-Wert - ISA intrinsische sympathikotone Aktivität - MEV maximaler exspiratorischer Fluß - Rtos oszillatorische Resistance Ein Teil der Daten wurde der Dissertationsschrift von Frau Janette Gehre entnommen. 相似文献
96.
Micropuncture studies on the filtration rate of single superficial and juxtamedullary glomeruli in the rat kidney 总被引:28,自引:0,他引:28
Summary Single nephron filtration rates of superficial and juxtamedullary nephrons were determined in high and low sodium rats. Single nephron GFR was calculated from TF/P inulin and tubular flow rate in superficial nephrons and single juxtamedullary GFR from corresponding data in long loops of Henle. In low sodium rats superficial nephron GFR was 23.5±6.4 (SD)×10–6 ml/min×g KW, juxtamedullary nephron GFR was 58.2±13.6 and total kidney GFR (C
In) was 0.94±0.16 ml/min×g KW. Using these single nephron values, total kidney GFR and a total number of 30,000 glomeruli per kidney, the number of superficial and juxtamedullary glomeruli was calculated to be 23,267 and 6,733, respectively. During high sodium diet superficial nephron GFR increased to 38.1±11.3 and single juxtamedullary GFR decreased to 16.5±6.6, total kidney GFR increasing to 1.01±0.24. Calculation again revealed the same distribution of the two nephron types. End-proximal TF/P inulin in superficial nephrons was 2.36±0.36 in low sodium and 2.31±0.28 in high sodium rats. Loops of Henle TF/P inulin and intratubular flow rate were inversely related: the highest TF/P inulin values and lowest intratubular flow rates were found in the descending limb. These data quantify the distribution of superficial and juxtamedullary nephrons on a functional basis and suggest a mechanism by which the kidney adjusts sodium excretion by altering the contribution of each nephron type to total kidney GFR.Supported by the Deutsche Forschungsgemeinschaft and the U.S. Department of the Army, through its European Research Office. 相似文献
97.
Atrial automaticity and atrioventricular conduction in athletes: contribution of autonomic regulation 总被引:2,自引:0,他引:2
Stein R Moraes RS Cavalcanti AV Ferlin EL Zimerman LI Ribeiro JP 《European journal of applied physiology》2000,82(1-2):155-157
Little is known about the sinoatrial automatism and atrioventricular conduction of trained individuals who present a normal
resting electrocardiogram. We used transesophageal atrial stimulation, a minimally invasive technique, to evaluate aerobically
trained athletes (n=10) and sedentary individuals (n=10) with normal resting electrocardiograms, to test the hypothesis that parasympathetic tone, as detected by heart rate variability,
could be associated with changes in sinoatrial automatism and atrioventricular conduction. Corrected sinus node recovery time
tended to be longer in athletes than in sedentary individuals, but this difference did not reach statistical significance.
The Wenckebach point occurred at a lower rate in athletes than in the controls. Over a 24-h period of measurement, the mean
RR interval was longer in the athletes than in the sedentary individuals. The mean square root of successive differences (rMSSD)
tended to be higher in athletes than in controls, but this difference did not reach statistical significance. There was a
moderate correlation (r=0.48, P < 0.05) between the index of atrioventricular conduction, the rate at the Wenckebach point, and the logarithmically transformed
rMSSD. Thus, as a corollary to its effects on the sinus node, where increased parasympathetic tone, decreased sympathetic
tone, and non-autonomic components may contribute to sinus bradycardia, it is possible that athletic training may also induce
intrinsic adaptations in the conduction system, which could contribute to the higher prevalence of atrioventricular conduction
abnormalities observed in athletes.
Accepted: 2 January 2000 相似文献
98.
生长因子作为评价胚胎质量的生物学标记物的研究 总被引:3,自引:0,他引:3
目的 研究表皮生长因子 (epidermalgrowthfactor,EGF)、转化生长因子 - β1(transforminggrowthfactor- β1,TGF -β1)、胰岛素样生长因子 -Ⅱ (insulin -likegrowthfactor-Ⅱ ,IGF -Ⅱ )做为评价小鼠胚胎质量生物学标志物的可能性。方法 取小鼠二细胞胚胎 ,分为正常和异常两组 ,体外培养至囊胚期 ,对胚胎的生长发育及着床能力进行形态学观测 ;检测胚胎培养液中三种生长因子的含量 ,研究生长因子含量与胚胎质量间的关系。结果 1.正常组胚胎培养液中EGF、IGF -Ⅱ的含量显著高于异常组 ,且EGF含量与胚胎生长发育的形态学指标呈正相关 ,但与着床指标相关不显著 ;2 .IGF -Ⅱ与胚胎生长发育及着床指标均呈正相关。 3.TGF - β1的含量两组间差异无显著性。结论 胚胎培养液中EGF、IGF -Ⅱ含量测定可反映胚胎生长发育能力 ,IGF -Ⅱ还可反映胚胎着床能力 ,从而有利于了解胚胎功能状态及生存潜力 ,为胚胎质量的检测提供了一条新的思路 相似文献
99.
身心因素与肠易激综合征患者生活质量的相关研究 总被引:1,自引:0,他引:1
目的调查肠易激综合征(IBS)患者生活质量状况并评估躯体及心理因素对它的影响。方法采用肠易激综合征生活质量量表(IBS-QOL)、临床症状问卷、艾森克人格问卷简式(EPQ-RSC)、简明心境问卷简式(POMS-SF)、医学应对问卷(MCMQ)对120例IBS患者进行测查,将IBS患者的心理健康水平(人格、情绪、应对)及躯体症状(肠道症状、肠外症状、睡眠障碍)与IBS患者生活质量进行相关分析。结果IBS患者IBS-QOL的8个因子和总分均显著降低(P<0.05),其中健康忧虑和饮食限制降低最为明显,除IBS症状外,肠外症状、睡眠障碍、精神心理异常在IBS患者中也很常见。心理因素中EPQ-RSC神经质(N)分、POMS中焦虑、抑郁等多项因子分及总分、MCMQ屈服积分与IBS-QOL总分呈负相关;躯体因素中IBS症状、肠外症状、睡眠障碍积分与IBS-QOL总分呈负相关。结论肠易激综合征患者的生活质量明显降低,除躯体症状外,心理功能失调也是决定患者生活质量的重要因素。 相似文献
100.
This investigation was designed to test (a) whether stimuli presented in the form of repeated blocks of habituation trials, as opposed to.1 single continuous series of stimuli, would produce a progressive decline. in amount of spontaneous recovery and trials to rehabituation of the skin conductance component of the orienting response; and (b) whether 30 or 50 post-habituation trials would produce a return of the orienting response which could be related In sensitization effects. Results showed that repeated habituations strengthened habituation as reflected in progressively decreasing spontaneous recovery across blocks, but not in speed of habituations. Further, neither 30 nor 50 post-habituation trials produced a return of the orienting response, although 30 such trials did result in increased skin conductance level. Discussion centers on whether habituation beyond asymptotic levels (‘below-zero’) within sessions was unambiguously obtained; relationships among stimulus intensity, frequency, and the return of the orienting response; and factors affecting measures of retention of habituation within sessions. 相似文献