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61.
The density dependence of the maximum expiratory flow-volume curve, functional residual capacity (FRC), and specific airway conductance (SGaw) were determined before and during bronchial provocation with ragweed extract in 27 subjects with ragweed hypersensitivity and a history of either bronchial asthma (16 subjects) or allergic rhinitis (11 subjects). Mean baseline SGaw was significantly lower while mean volume of isoflow (Visov) and FrC were significantly higher in subjects with bronchial asthma. During antigen challenge, 10 of 16 subjects with bronchial asthma (63%) and five of 11 subjects with allergic rhinitis (45%) showed a greater than 35% decrease in SGaw ("reactors"): mean relative decreases in SGaw from baseline were 46% and 53%, respectively. The remaining subjects showed a less than 35% decrease in SGaw ("nonreactors") with mean relative decreases of 9% (allergic asthma) and 6% (allergic rhinitis). Mean Visov increased in all subjects with bronchial asthma and in eight of 11 subjects with allergic rhinitis. A significant increase in FRC (6%) was seen only in the "reactors" with bronchial asthma. Following antigen challenge, the beta adrenergic agonist, isoetharine, increased SGaw and decreased Visov. We conclude that in asymptomatic subjects with ragweed hypersensitivity, (1) central and peripheral airway function is more abnormal in subjects with bronchial asthma than in subjects with allergic rhinitis, (2) subjects of both groups show quantitatively and qualitatively comparable airway responses during antigen challenge with a decrease in SGaw or an increase in Visov, possibly representing increase in central and/or peripheral airflow resistance, respectively, (3) Visov may be a more sensitive indicator of airway response to antigen challenge than SGaw, and (4) the bronchodilator effects of a beta adrenergic agonist on antigen-induced bronchospasm are similar in both groups. 相似文献
62.
Cebus monkeys of 3 different age groups were trained to perform an automated behavioral task (delayed response), intended to measure recent memory ability. In in initial study, the aged monkeys (18 years and older) exhibit prprogressively greater performance impairments (relative to young monkeys) as they were required to remember the location of a visual stimulus for increasingly longer durations (0 to 20 sec). This deficits replicated previously published results from aged Rhesus monkeys and appeared similar to the primary memory deficits reported in elderly humans and demented patients. In subsequent studies, the effects of three different cholinomimetics were evaluated for their ability to improve the aged monkey's performance on this task. Each monkey was tested under several acute doses of the cholinergic precursor, choline, the anticholinesterase, physostigmine, and the cholinergic muscarinic receptor agonist, arecoline. The results revealed clear differences in the ability of these drugs to improve performance on this task. Choline exerted no apparent effects in the aged monkeys at any dose tested. Physostigmine clearly enhanced performance in certain aged monkeys, but the optimal dose varied dramatically between subjects, replicating previously published results with aged Rhesus monkeys and humans. Arecoline produced clear improvement within a restricted dose range, with little variation in optimal dose between subjects. In addition to demonstrating differences in the effects of different cholinomimetics on memory performance in aged primates, these data also suggest a possible rationale for future investigations. Assuming that each of these drugs primarily affected cholinergic function in the manner conventionally attributed, these data suggest that, within the cholinergic system, the more directly one stimulates the receptor, the more one might expect robust and consistent effects on memory performance in aged subjects. 相似文献
63.
电镜观察了不同禁水时间老龄大鼠下丘脑视上核和室旁核分泌神经元,即加压素和催产素神经元及胶质细胞的超微结构变化,结果显示,禁水6与12h后,上述两核团中的分泌神经元胞体增大,胞质中粗面内质网(RER)排列紧密且规则,高尔基(Golgi)器的未成熟分泌颗粒及神经分泌颗粒增多,轴突内神经分泌颗粒少见,胶质细胞成份减少,突起回缩;相邻两神经元胞膜直接接触,质膜并列现象及突触增多,而在禁水24h后,神经元胞体内的神经分泌颗粒有减少,轴突中的神经分泌颗粒却增多并聚集成膨大区域,以上结果提示老龄大鼠视上核和室旁核的分泌神经元在禁水时其合成激素的功能是活跃的,而且催产素神经元的结构变化与加压素神经元结构变化是相似的,胶质细胞的结构变化为神经元质膜并列及突触的形式提供了有利条件。 相似文献
64.
目的:了解长寿老人主观幸福感及其影响因素。方法:采用横断面整群抽样调查方法,对732例都江堰市90岁以上老人进行费城老年中心信心量表(PGCMS)、家庭关怀度指数(APGAR)、中文版简易智能状态检查(MMSE)、日常生活能力量表(ADL)及社会支持量表(SSRS)调查。结果:PGCMS在90-108岁老人中呈负偏态分布,PGCMS总分为1-23分,M(QL-QU)为17(13-19)。各年龄组间PGCMS的差异无统计学意义,PGCMS与SSRS中的主观社会支持、客观社会支持及APGAR、MMSE、ADL中的躯体生活自理分量表的相关有统计学意义。结论:PGCMS在90-108岁老人中呈负偏态分布,分值不随年龄的增加而变化。对90—108岁长寿老人主观幸福感有影响的因子及强度依次为主观社会支持、客观社会支持、认知功能状况、家庭关怀情况及日常生活中躯体生活自理能力。 相似文献
65.
The present study was a longitudinal study of age-related changes in performance of the 5-choice serial reaction time task, a test of visual attention. Following acquisition of the task, animals were tested on two occasions on their ability to perform the 5-choice task. In Test 1 (Young: 7 months; Aged: 13–14 months) no age-related effects on baseline performance were revealed. However, increasing the attentional load of the task revealed an impairment in choice accuracy by animals of the Aged group. In Test 2 (Young: 10–11 months; Aged 23–24 months), animals of the Aged group were significantly impaired on the baseline schedule of the task compared to the Young group. The deficit in accuracy on the task could be improved in the Aged animals by decreasing the attentional load. The results of the present study suggest a deficit in attentional function as a result of the aging process, markedly similar to that observed following lesions of the basalo-cortical cholinergic system. 相似文献
66.
Dynorphin has a well-established role in feeding and gustation. Alterations in taste perception and feeding behavior are common with age. We hypothesized that proDynorphin gene expression in brain areas involved in taste and feeding declines with age. Male Sprague-Dawley rats were housed individually with ad libitum access to food and water. Brain punches of the selected regions were dissected out in groups of rats aged 4–6, 12–14 and 18–21 months. ProDynorphin mRNA (measured using a cDNA probe) decreased significantly with age in arcuate nucleus and amygdala; increased significantly with age in hippocampus; and was not significantly affected in nucleus of the solitary tract, cortex, caudate putamen or hypothalamic paraventricular nucleus. These data suggest an age-related decrease in the synthesis of dynorphin in two brain regions strongly associated with feeding behavior, and an increase in dynorphin synthesis in a brain region associated with learning and memory. 相似文献
67.
We used volumetric magnetic resonance imaging to examine sex differences in prefrontal tissue volumes of healthy aged and patients with Alzheimer’s disease (AD). Healthy subjects had greater total prefrontal volume than AD, and men had greater total prefrontal volume than women (ps ≤ 0.02). This was true for both gray and white matter volumes. There were no interactions between group and sex for total prefrontal volume. An exploratory analysis of each group suggested that sex differences in both gray and white matter in healthy aging are not sustained in AD. 相似文献
68.
We have previously found that halothane-relaxant anaesthesia in elderly patients causes a change towards a hyperkinetic circulation, with a decrease in the arterial-mixed venous oxygen content difference. This could be attributed to vasodilation. In the present study the splanchnic contribution to these changes was investigated. Nine patients were studied during halothane-relaxant anaesthesia prior to surgery. During anaesthesia splanchnic blood flow was markedly reduced, while splanchnic oxygen uptake decreased only moderately compared with the awake level. This resulted in an increase in splanchnic oxygen extraction. It is concluded that the splanchnic vascular bed does not contribute to the "hyperkinetic" circulation during halothane anaesthesia. 相似文献
69.
目的 比较分析我国中年和老年女性抑郁倾向及影响因素的差异性,为有针对性的改善中年与老年女性群体的心理健康水平提供参考。方法 选取中国健康与养老追踪调查(CHARLS)2018年数据,以45~59岁中年女性和≥60岁老年女性为研究对象,采用流行病调查中心抑郁量表(CES-D)评估其抑郁倾向。中年和老年女性抑郁倾向的比较采用均值检验,使用倾向性评分匹配法(PSM)对中年和老年女性进行匹配后,进一步探索其组间的差异,采用稳健Tobit回归模型探究抑郁倾向的影响因素。结果 7 964例中老年女性的CES-D评分为(9.53±6.86)分。其中,中年女性、老年女性CES-D评分分别为(9.13±6.62)分、(9.96±7.09)分,老年女性的抑郁倾向评分高于中年女性(t=-5.361,P<0.001)。稳健Tobit回归结果显示,文化程度、居住地、健康自评、身体残疾、慢性病、因身体疼痛而苦恼、BADL受损、IADL受损、是否与配偶或同居者一起生活、家庭成员数量、现有负债、地带分布是中年和老年女性抑郁倾向共同的影响因素。年龄及其二次项、子女数量、有无农业自雇以外的工作是中年女性抑郁倾向的影响因素; 每月来看望1次及以上的子女数量、是否照顾孙子女、是否有社交活动、是否上网、是否退休是老年女性抑郁倾向的影响因素。结论 我国老年女性的抑郁倾向较中年女性明显,且影响因素存在差异性。应针对不同人群特征,提供更有针对性的预防策略,促进中年和老年女性心理健康良性发展。 相似文献
70.