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71.
Aim: This article reviews research centred around juvenile bipolar disorder with particular reference to diagnostic difficulties. Putative deficits are scrutinized with respect to trait likelihood and the roles of neuropsychology and neuroimaging in enhancing our understanding of juvenile bipolar disorder are discussed. Methods: Search terms including childhood, adolescent, youth and juvenile combined with the terms ‘bipolar disorder’, mania, depression and hypomania were used to identify relevant studies in MEDLINE and PsychLit. Results: Over recent years research into this relatively new disorder has increased phenomenally. Key issues within the field include diagnostic specificity, the heritability of the disorder, the impact of comorbidity and the implications of neuropsychological and neuroimaging findings. Conclusion: Despite concerning controversies in literature the diagnosis of bipolar disorder in children and adolescents as compared with adults, promising future research directions include better neurological characterization of the disorder through the application of findings from clinical populations, neuropsychological and neuroimaging research.  相似文献   
72.
Lipid peroxidation in the brain cortex, striatum, hippocampus, and hypothalamus of rats of the KLA and KHA lines which were distinguished by their strategies of adaptive behavior was investigated following emotional-painful stress. Significant long-term changes in lipid peroxidation were shown to occur in the brain. These had a phase character and depended on the behavioral characteristics of the animals. The investigated brain regions were characterized by different reactions of lipid peroxidation to the stress. The induced depressive-like states (on the 21st day after the stress) in rats of the KLA and KHA lines were distinguished by the largest changes in lipid peroxidation in the striatum and hypothalamus and in the striatum and hippocampus, respectively. One could conclude on the basis of these results that both identical and different mechanisms of formation and development of depression existed in the animals with different behavioral strategies.  相似文献   
73.
This paper describes a response directed stress management intervention (SMI) in the form of a Jungian based preference awareness education (PAE). It uses the Insights System of personality types to increase awareness of behaviour and communication preferences of self and different others. Eighteen self‐recruited academic employees participated for 7 weeks and received feedback about work preferences and personality type. The aim was to reduce perceptions of stress and interpersonal stress and to increase feelings of job satisfaction and interpersonal satisfaction. The data were analysed using two‐tailed t‐tests. No significant findings were observed for the total sample after training, however, interesting results were found for certain sub‐sample groups. Extravert‐thinking types, reported decreased stress levels (p > 0.018), and participants suffering high stress/interpersonal stress pre‐PAE, reported decreased stress levels (p > 0.010–0.018). Participants suffering low job/interpersonal satisfaction pre‐PAE, reported increased job satisfaction (p > 0.015–0.016). These results suggest that individuals who report high levels of stress and dissatisfaction are most likely to benefit from this type of intervention. Future PAE research might: (a) use pilot studies to meet the intervention preferences of employees that are reluctant to participate in SMIs; (b) include a wait‐list control group; use: (c) a follow up education/measures; (d) and organizational level (stressor directed) SMIs at the same time as response directed initiatives. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
74.
Previous work suggests that secretory immunoglobulin‐A (S‐IgA) reactivity is inversely related to the perceived demands of the stressor. The Defined Intensity Stressor Simulation (DISS) comprises eight stressor modules, and allows for the manipulation of stress either through increasing the number of modules, or increasing the workload of the modules. The current study assessed the effect of increasing the workload of four modules upon S‐IgA reactivity and perceived demands. Participants (N = 14) attended three sessions on consecutive days where they provided a timed saliva sample immediately before and after 5 min on the DISS at low, medium and high workload. Following each session participants recorded their perceptions of the task with regard to workload and levels of stress and arousal. Perceived workload and stress, but not arousal, increased in accordance with increases in workload, however, differential S‐IgA reactivity was observed. Low workload resulted in a slight increase in S‐IgA secretion; medium workload elicited significant up‐regulation, while down‐regulation of S‐IgA occurred following high workload. As DISS is analogous to a variety of working environments it is suggested that the observed S‐IgA reactivity is indicative of how individuals react to multi‐tasking environments when faced with increases in objective or perceived workload demands. As S‐IgA levels are related to protection from illness, down‐regulation of S‐IgA in those who perceive greater demands may lead to greater vulnerability to ill‐health. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
75.
76.
BACKGROUND: Recent research has addressed the issue of subtyping juvenile bipolar disorder (JBD). Accordingly, we set out to find out, in a naturalistic sample of bipolar children and adolescents with mania and mixed mania, whether the most useful subtyping should be based on clinical features (elated vs. irritable) or course (episodic vs. chronic). METHODS: We studied 136 patients, 81 male patients (59.6%) and 55 female patients (40.4%), mean age 13.5 +/- 2.9 years, meeting the DSM-IV diagnosis of bipolar disorder, assessed by a structured clinical interview (Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version [K-SADS-PL]). RESULTS: Regarding course, 77 patients (56.6%) had an episodic course and 59 patients (43.4%) had a chronic course. Patients with chronic course were significantly younger, had an earlier onset of JBD, and presented a more frequent comorbidity with disruptive behavior disorders. According to the prevalent mood disturbance, 75 patients (55.1%) showed an elated and 61 patients (44.9%) showed an irritable mood. Elated mood was more frequent in patients with episodic course, whereas irritable mood was more frequent in the patients with chronic course. CONCLUSIONS: These findings suggest that chronic versus episodic course may be a putative differential feature. Further validation of such a distinction would require prospective studies, temperament evaluation, gender and neurobiologic approaches, and differential psychopharmacologic assignment and response.  相似文献   
77.
Mapping brain size and cortical gray matter changes in elderly depression.   总被引:1,自引:0,他引:1  
BACKGROUND: In elderly depression, volumetric brain imaging findings suggest abnormalities of the frontal lobe, particularly the orbitofrontal cortex, and the hippocampus. No studies to date have mapped cortical abnormalities over the entire brain surface in major depression. Here, we conducted detailed spatial analyses of brain size and gray matter within the cortical mantle in elderly patients with major depression. METHODS: High-resolution, three-dimensional, structural magnetic resonance imaging data and cortical pattern matching methods were used in 24 depressed elderly patients and 19 group-matched controls to measure local brain size and proportions of gray matter at thousands of homologous cortical surface locations. RESULTS: Prominent brain size reductions were observed in the depressed subjects in the orbitofrontal cortex bilaterally. Cortical gray matter measurements revealed significant gray matter increases in the orbitofrontal cortex, adjacent to focal trend level significant decreases of gray matter in the same region. Depressed patients also exhibited significant gray matter increases in parietal cortices, as well as the left temporal cortex. CONCLUSIONS: Complex cortical changes may contribute to the brain size reduction of the orbitofrontal cortex and to the gray matter abnormalities detected in orbitofrontal cortex and temporoparietal cortices, thereby providing a potentially new window into the pathophysiology of elderly depression.  相似文献   
78.
BACKGROUND: Reactive oxygen species play a major role in the development of endothelial dysfunction. It is as yet unspecified whether increased oxidative stress contributes to endothelial dysfunction of the renal vasculature in patients with type 2 diabetes. METHODS: Renal haemodynamics were studied in 20 patients with type 2 diabetes and arterial hypertension (age 62 +/- 5 years) and 20 non-diabetic hypertensive patients at baseline and following infusions of the nitric oxide synthase inhibitor, N(G)-monomethyl-L-arginine (L-NMMA; 4.25 mg/kg); the substrate of nitric oxide synthase, L-arginine (100 mg/kg); and the antioxidant, vitamin C (3 g, co-infused with L-arginine 100 mg/kg). RESULTS: The response of renal plasma flow (RPF) to L-NMMA (-54 +/- 62 and -45 +/- 42 ml/min/1.73 m(2); P = NS) and L-arginine (+46 +/- 36 and +49 +/- 25 ml/min/1.73 m(2); P = NS) was not different between diabetic and non-diabetic patients. In contrast, vitamin C induced a more pronounced increase in RPF in diabetic than in non-diabetic patients when co-infused with L-arginine (+71+/-47 and +43+/-33 ml/min/1.73 m(2); P<0.05). CONCLUSIONS: The difference in the response of renal perfusion to an antioxidant suggests increased formation of reactive oxygen species and thereby reduced nitric oxide bioavailability in the renal vasculature of patients with type 2 diabetes.  相似文献   
79.
抑郁患者血清皮质醇与血压在应激前后的变化   总被引:2,自引:0,他引:2  
目的研究抑郁患者血清皮质醇浓度、血压在应激前后的变化以及它们之间的关系。方法分别在安静状态、心理应激状态和心理应激后 (恢复状态 )测量抑郁组和对照组的血清皮质醇浓度、血压 ,比较两组上述指标的差异 ,以及心理应激前后的变化。心理应激以规定时间内的计算试验模拟 ,血清皮质醇以酶联免疫试验检测 ,血压为常规检测。结果 1.皮质醇 :抑郁组在安静状态、应激状态、恢复状态的皮质醇浓度显著高于对照组 (P <0 .0 5 ) ,抑郁组应激前后皮质醇浓度的波动显著小于对照组 (P <0 .0 5 )。2 .收缩压 :安静状态和恢复状态时抑郁组的收缩压显著高于对照组 (P <0 .0 5 ) ,应激状态时两组无统计学差异 ;应激前后收缩压的波动两组无统计学差异。 3 .舒张压 :抑郁组在安静状态时舒张压显著高于对照组(P <0 .0 5 ) ,在应激状态和恢复状态时两组无统计学差异 ;应激前后舒张压的波动两组无统计学差异。结论抑郁患者存在基础血压升高 ,此现象可能与抑郁患者血清皮质醇浓度升高有关。  相似文献   
80.
目的 探讨质子磁共振波谱(1HMRS)在诊断创伤后应激障碍(post traumatic stress disorder,PTSD)患者海马神经元异常中的价值。方法 对19例PTSD患者及19例健康对照组行常规MRI和1HMRS检查。结果 PTSD患者MRI检查未出现信号的异常。19例患者两侧海马均显示NAA/Cr明显减低,与健康对照组相比,差异有统计学意义(P〈0.01);而患者两侧海马的Cho/Cr与健康对照组相比,差异无统计学意义(P〉0.05)。结论 1HMRS揭示了PTSD时海马存在着神经元的丢失或功能紊乱,而这些改变是构成PTSD的神经生物学基础之一。  相似文献   
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