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81.
82.
Eighty treatment-seeking adults age 60 or over with panic disorder, generalized anxiety disorder, and mixed anxiety states (generalized anxiety with panic attacks, panic disorder with secondary generalized anxiety) completed a clinical assessment and battery of self report measures. Several hypotheses were tested from the domains of distinguishing symptoms, associated features, and rates of comorbidity with other disorders. Greater between- than within-group variance was found on a subset of measures suggesting that the distinction between GAD and PD is generally valid in the older adult population. Higher scores on measures of sympathetic arousal, agoraphobic avoidance, and rates of comorbid somatization disorder and alcohol dependence distinguished those with PD from those with GAD. Higher scores on measures of depression and hostility, but not trait anxiety or worry, distinguished the GAD group. Results indicate that distinguishing features of GAD and PD in older treatment-seeking adults may be fewer and slightly different from those of younger adults.  相似文献   
83.
To investigate the effect of fluoxetine on serotonergic sensitivity in obsessive-compulsive disorder (OCD), the partial serotonin agonist metachlorophenylpiperazine (mCPP) was compared to placebo under double-blind conditions in six patients with OCD before and during treatment with fluoxetine. Readministration of oral mCPP (0.5 mg/kg) after at least 12 weeks of fluoxetine treatment did not increase obsessive-compulsive (OC) symptoms, in contrast to exacerbation of OC symptoms produced by mCPP before treatment. Chronic fluoxetine treatment resulted in a significant increase in prolactin and cortisol response to mCPP. This may be accounted for, however, by substantially increased plasma mCPP levels during fluoxetine treatment. Chronic fluoxetine treatment diminished the behavioral sensitivity to mCPP and did not diminish, but may have partially normalized, the neuroendocrine response to mCPP in patients with OCD. These adaptive homeostatic effects may reflect fluoxetine's antiobsessional mechanism.  相似文献   
84.
The effects of double breath inhalation of a 35% CO2 mixture in oxygen and placebo air inhalation were compared in 14 women seeking treatment for marked premenstrual dysphoric changes who did not have panic disorder and 12 control women. The first exposure to CO2 inhalation induced a panic attack reaction (severe subjective anxiety with autonomic symptoms) in 9 of 14 women with premenstrual dysphoria but none of the controls. Neither patients nor controls panicked in response to the air inhalation. Control subjects experienced mild anxiety and/or somatic symptoms after CO2 inhalation, but these did not resemble panic attacks and were clearly different from the response of the patient group.  相似文献   
85.
Animals placed in complex environments develop greater numbers of visual cortex synapses per neuron than animals housed in standard cages. Increased numbers of synapses could theoretically arise from (i) active formation of new synapses, or (ii) selective stabilization of constitutively produced synapses. The postsynaptic location of polyribosomal aggregates appears to be an indicator of newly forming synapses. In developmental synaptogenesis and adult reactive (to injury) synaptogenesis, polyribosomes are more frequently found at spine synapses and are more likely to appear in the spine head and stem. In the visual cortex of rats from complex environments, there was a greater frequency of spine synapses associated with polyribosomes, relative to rats from individual or group cages. Furthermore, a greater percentage of these spines had polyribosomes in the head and stem region. This suggests that synapses in this region may be actively induced by neural activity arising from the complex environment experience.  相似文献   
86.
We have recently reported the X-ray crystal structure of a fragment of the fusion protein (F) of Newcastle disease virus (NDV). This work describes the methodology involved in the production and crystallization of that protein in recombinant form. The full-length cDNA of NDV-F was cloned and the ectodomain expressed in both CHO-K1 and Lec-3.2.8.1 cells. The recombinant protein, secreted as a single-chain polypeptide F0', was purified using a c-myc antibody affinity column followed by gel filtration chromatography. Electron microscopic imaging showed the F0' product to consist of unaggregated club-shaped particles. Trypsin treatment of F0' could be used to produce disulfide-linked F2 and F1' chains. However, imaging revealed extensive rosette-like aggregation of the trypsin-treated material, indicative of a conformational change. Only the non-trypsin-treated product was thus suitable for crystallization and two crystal forms were obtained, diffracting to ca. 3.5 and 4.0 A, respectively. Both crystal forms were used in the structure determination.  相似文献   
87.
The natural history of microalbuminuria in adolescents with type 1 diabetes   总被引:3,自引:0,他引:3  
OBJECTIVE: To describe the natural history of urinary albumin excretion measured initially during the first decade of type 1 diabetes in adolescents and to identify predictors of the onset and progression of microalbuminuria (MA) in this population.STUDY DESIGN: A retrospective cohort follow-up study was done on 76 adolescents whose albumin excretion rate (AER) had been determined in the first decade of their diabetes. Subjects were monitored for a mean of 6 years after initial AER testing. Those with MA were compared with a group with similar age, sex, and diabetes duration who initially had normoalbuminuria (NA). RESULTS: Of the 28 with initial MA, 9 (32%) regressed (8 to within the NA range), whereas MA was persistent in 10 (36%) and progressed in 9 (32%), 5 to overt proteinuria. Of the 47 who had initial NA, MA developed in 14 (30%) and overt proteinuria in 3 (6%). With MA status at follow-up as the dependent variable, multiple regression analysis showed that initial AER (P =.0002) and hemoglobin A1c (P =.02) measured at the same time were significant independent variables. CONCLUSIONS: These data suggest that in adolescents: (1) MA detected in the first decade of disease will persist or progress in the second decade in approximately two thirds of patients, and new MA will develop in a third of those initially normoalbuminuric; and (2) the appearance, persistence, or progression of MA is influenced in large part by metabolic control assessed by hemoglobin A1c both at initial MA screening and throughout the course of diabetes. This underlines the need for MA screening starting early in the course of type 1 diabetes in adolescents and for maintenance of good metabolic control.  相似文献   
88.
Pediatric obesity is a major public health threat. Obese children and adolescents are at increased risk for many medical and surgical conditions. These conditions may affect their quality of life and life expectancy. The rapidly progressive nature of type 2 diabetes mellitus within the first 5?years?of obesity diagnosis is particularly concerning. Because health risk increases with degree of obesity, adolescents who may be eligible for more aggressive obesity treatment should be identified and counseled.  相似文献   
89.
    
SW 《校园心理》2005,3(5):50-51
黑暗!黑暗!!黑暗!!!这样的世界看不到半点光明。孤独的舞者终究还是孤独地倒下,然后又孤独地消失。黑暗呀,为什么老是缠绕着我?一声“妈妈”划破了天际,却也突不出黑暗的包围。谁来应我一声呀,妈妈,你在哪里呀?我的心在不停地挣扎,告诉自己:“不怕,不怕。”可这是在黑暗里呀,周  相似文献   
90.
The correlation of JAK2V617F with a proportion of chronic myeloproliferative disorders has generated numerous studies focused on the development of molecular-based assays for JAK2V617F detection. The current parallel study comparatively evaluated 3 JAK2V617F molecular detection methods. Genomic DNA from blood or bone marrow was assayed by 3 laboratories using allele-specific polymerase chain reaction (AS-PCR) or kit-based restriction fragment length polymorphism methods, which used polyacrylamide gel or capillary electrophoresis analysis. In addition, samples were sequenced in 2 of the laboratories. Results found 100% concordance among the 3 methods, with analytic sensitivities of 5% for both kit methods and 0.01% for AS-PCR. The kitbased assays detect JAK2V617F with equal sensitivity regardless of analysis method, and, despite greater sensitivity of AS-PCR, all 3 methods yielded 100% concordant results for this 36-sample set. Consistent with other reports, direct sequencing was insufficiently sensitive to serve as an initial diagnostic tool for JAK2V617F detection.  相似文献   
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