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71.
脂肪组织除了通过其力学特征或机械功能对周边组织器官产生影响以外,还可以凭借非物理性的内分泌功能通过脂肪因子输出信号方式有效地建立起与呼吸系统等远程器官的互作信息网络,进而参与多种肥胖相关疾病的发生与发展。作为内分泌领域的突破性进展之一,脂肪组织的内分泌功能受到生命科学领域的关注。近年来,多项流行病调查研究揭示了肥胖是造成慢性阻塞性肺疾病(COPD)等呼吸系统疾病肺功能损害重要的危险因素。基于此,本文将分别梳理脂联素、瘦素、内脂素等脂肪因子在COPD中的作用机制,从脂肪组织内分泌功能角度为COPD的防治研究提供新思路。  相似文献   
72.
目的 分析在新型冠状病毒肺炎流行背景下,2016年4月—2022年3月国内深圳市和济南市流感流行特点,了解我国南北方地区流感流行差异。 方法 使用深圳市和济南市国家级哨点医院2016—2022监测年度流感样病例(ILI)和流感病原学监测资料,分析流感流行特征和趋势。 结果 2016—2022监测年度深圳市和济南市国家级哨点医院的门急诊病例中流感样病例百分比(ILI%)分别为2.25%、3.45%。两地区ILI%最高的年份均为2021—2022监测年度。ILl年龄构成均以0~4岁为主(分别占40%、46%)。按月分析两地区流感病毒分离阳性率与ILI%变化的相关性,两者趋势均存在正相关(r=0.238,P<0.05;r=0.425,P<0.001)。两地区不同监测年度流感优势毒株型别均不相同,呈交替变化,但每年流行的型别及高峰期的优势毒株型别基本一致。 结论 2020—2021监测年度即新型冠状病毒肺炎流行初期,深圳市和济南市流感活跃程度明显低于往年平均水平且流行毒株型别单一,其余监测年度基本符合我国南、北方地区流感流行特征。  相似文献   
73.
This review examines the role of serotonin (5-HT) in depression. Dysfunction of serotonergic neurons has been implicated as one of the causes of endogenous depression. Since serotonergic neurons innervate the hypothalamus and these neurons send collaterals to several other brain areas, it is possible that hypothalamic sites which control hormone secretion receive the same serotonergic afferents that innervate other limbic areas in the brain. Several investigators have devised neuroendocrine challenge tests measuring the effect of 5-HT agonists on plasma cortisol and prolactin in depressed patients. These tests help to identify dysfunctional 5-HT neurons, and are a "window into the brain." The secretion of cortisol and prolactin is increased predominantly by 5-HT1 receptors. However, changes in 5-HT2 receptors have also been implicated in depression. Results from our laboratory and by others suggest that brain serotonergic neurons stimulate renin and vasopressin secretion by activation of 5-HT2 receptors. Therefore, the renin and vasopressin response to 5-HT agonists should be included in neuroendocrine tests of serotonergic function in affective disorders. Since antidepressants produce a decrease in the density of 5-HT2 receptors, renin and vasopressin could be used to evaluate the antidepressant potential of new drugs.  相似文献   
74.
In previous reports weanling female rats fed a high-fat diet had a delayed response to hypothalamic knife cuts. In the present report similar cuts in similar rats fed a standard low fat diet became overweight without delay, suggesting that dietary fat is a critical variable in juvenile onset obesity. Adult rats given knife-cuts comparable to those in the weanlings gained weight far more rapidly and achieved higher weights than did those cut as weanlings, suggesting that appetite modulating axons can develop after weaning. Finally, group vs single housing did not influence the age of onset or the magnitude of knife-cut obesity.  相似文献   
75.
Pastore LM  Carter RA  Hulka BS  Wells E 《Maturitas》2004,49(4):292-303
OBJECTIVE: To examine the prevalence and correlates of self-reported urogenital symptoms (dryness, irritation or itching, discharge, dysuria) among postmenopausal women aged 50-79. DESIGN: A cross-sectional analysis based on n=98,705 women enrolled in the US-based Women's Health Initiative observational study and clinical trials. Urogenital symptoms, symptom severity (mild, moderate, severe), and all covariates were self-reported through questionnaires at enrollment. Prevalence rates of each urogenital symptom were examined and logistic regression was used to identify potential correlates. RESULTS: Prevalence rates for each symptom were: dryness, 27.0%; irritation or itching, 18.6%; discharge, 11.1%; and dysuria, 5.2%. Four factors were correlated with two or more symptoms: Hispanic ethnicity (adjusted odds ratio (AOR)=2.1-3.1 versus white women across all symptoms), obesity (AOR=2.2 severe discharge versus none, AOR=3.6 severe irritation/itching versus none), treated diabetes (pills or shots) compared to no diabetes (AOR=2.4 severe dysuria versus none, AOR=3.2 severe irritation/itching versus none), and vaginal cream HRT/ERT compared to those who never used HRT/ERT (AOR=4.4 severe dryness versus none, AOR=4.6 severe irritation/itching versus none). Factors not associated with the symptoms included sexual activity, age, years since menopause, current smoking, marital status, gravidity, and natural versus surgical menopause. CONCLUSIONS: This is the first report to document urogenital symptoms by race/ethnicity among an exclusively postmenopausal population. We found an elevated prevalence of urogenital symptoms among women who are Hispanic, obese, and/or diabetic. Confirmation of our findings in these subgroups, and, if confirmed, analysis on why these populations are at greater risk, are areas for future research.  相似文献   
76.
To evaluate the influence of flavor on ad lib consumption and on associated changes in body weight, female baboons, 7–15 years of age, served in two experiments with seven monkey chows which were identical except for flavor: lemon, orange, apple, sugar, fruit punch, chocolate, and unflavored. In the first experiment, two groups of animals (n=7 and 4) received five of the seven flavors, presented in daily pair-wise combinations. Analysis of quantities consumed demonstrated marked and consistent flavor preferences in individual baboons. Although specific preference varied between animals, total amounts consumed of the various flavors differed significantly, with rank ordering clearly evident. Overall food intake and body weights increased significantly over baseline values obtained with a standard, unflavored chow. In the second experiment, three baboons received chow of a preferred flavor for nine weeks. Amounts consumed and body weights increased significantly over baseline. These results indicate that flavored chows may be useful for producing a nonhuman primate behavioral model of obesity and for inducing animals to eat otherwise unpalatable diets.  相似文献   
77.
瘦素(leptin)与肥胖   总被引:2,自引:2,他引:2       下载免费PDF全文
Obesity is a severely public health problem the whole society faces, and it is correlated closely with many diseases, such as diabetesⅡ, hypertension, coronary heart disease,gallqtone, and so on.Therefore it threatens people‘ s survival quality severely. Obesity is a multiple - factor disease including genetic, metabolic and behavioral factor, and the gene is the main determining factor. With the development of molecular biology technique, people have founded several genes involved in obesity. Among these genes, the research on obese gene is the most profound. The protein leptin is the expression product of the obese gene.This review elucidates the structure, the main biological function, the mechanism of leptin and it‘‘s relationship with obesity.  相似文献   
78.
中国H3N2亚型流感病毒烷胺类药物耐药性研究   总被引:7,自引:0,他引:7  
目的 通过监测我国自1989年以来H3N2亚型流感病毒对烷胺类药物产生耐药性的情况,为流感的临床治疗用药提供一定的指导.方法 从我国流感监测网络中所分离的H3N2亚型流感病毒中随机选择了584株病毒,通过对病毒与烷胺类药物耐药性相关的M2基因进行序列测定,同时在细胞水平上通过药物敏感试验分析病毒对药物的敏感性,从而分析病毒产生耐药的情况.结果 1989-1999年没有发现对烷胺类药物产生耐药性病毒株,但2003年对烷胺类药物产生耐药性病毒株的比例从2002年的3.4%升到了56.0%,2005年达到77.6%.结论 自2003年以后,流行的H3N2亚型流感病毒超过50%的病毒产生了对烷胺类药物的耐药性,并且耐药病毒株的比例呈逐年升高的趋势.  相似文献   
79.
本研究应用免疫细胞化学技术观察了雌性成年SD大鼠下丘脑内5-HT1A受体亚型(5-HT1AR)和5-HT2AR免疫阳性结构的分布。结果显示:5-HT1AR免疫阳性神经元在视前区大细胞核、视前室周核、视上核和下丘脑外侧前核等核团内密集分布。在内侧视前核、外侧视前区、下丘脑室周核、下丘脑外侧区、背内侧核、腹内侧核、结节核、结节乳头体核、乳头体内侧核和乳头体外侧核等结构内也有较多的分布;而在正中视前核、视交叉上核、下丘脑室旁核、下丘脑背侧核、弓状核、乳头体上核和乳头体前核等部位有散在的分布。与5-HT1AR不同,5-HT2AR免疫阳性反应产物主要见于纤维和终末,阳性胞体少且染色淡。5-HT2AR阳性胞体见于下丘脑室旁核、视上核、腹内侧核、结节核、视前内侧区、外侧区、外侧前核、下丘脑背内侧核等处。另外,在视前区前内侧视前核、视交叉上核背侧和外侧可见围绕血管分布、密集成团簇状、带有大小不同膨体的阳性神经纤维缠结。本文结果提示5-HT1AR阳性结构广泛地分布于大鼠下丘脑,而5-HT2AR在下丘脑分布较为局限。二者不同的分布特点,提示它们可能介导5-HT在下丘脑的不同生理功能。  相似文献   
80.
Binge eating disorder (BED), characterized by ingestion of very large meals without purging afterwards, is found in a subset of obese individuals. We showed previously that stomach capacity is greater in obese than in lean subjects, and in this study, we investigated capacity in obese individuals with BED. We also determined ad-libitum intake of a test meal until extremely full. Furthermore, we measured various appetitive hormones (insulin, leptin, glucagon, CCK, ghrelin) and glucose before a fixed meal and for 120 min afterwards. An acetaminophen tracer was used to assess gastric emptying rate. We compared three groups of overweight women: 11 BED, 13 BE (subthreshold BED), and 13 non-binge-eating normals. The BED individuals had the largest stomach capacity as assessed by either maximum volume tolerated (P=.05) or by gastric compliance to pressure (P=.02) using an intragastric balloon. Although test meal intake did not differ between groups, it correlated (P=.03) with gastric capacity. The BED group showed a tendency (P=.06) to have greater area under the curve (AUC) and had higher values at 5 and 60 min (P<.05) for insulin compared to normals. Moreover, the BED subjects had lower ghrelin baselines premeal, and lower AUC for ghrelin, which then declined less postmeal than for the normals (P<.05). None of the other blood values differed, including glucose, leptin glucagon, and CCK, as well as acetaminophen, reflecting gastric emptying. The lower ghrelin in BED, although contrary to what was expected, is consistent with lower ghrelin in obesity, and suggests down-regulation of ghrelin by overeating. The lack of differences in CCK is consistent with the lack of differences in gastric emptying rate, given that CCK is released when nutrients reach the intestine. The results show that BED subjects have a large gastric capacity as well as abnormalities in meal-related ghrelin and insulin patterns that may be factors in binge eating.  相似文献   
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