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81.
This experiment tested the hypothesis that inotropic cardiovascular reactivity to stress is related to performance on heartbeat discrimination tasks. The experiment also compared the efficacy of a specific modification of two popular heartbeat discrimination paradigms, Whitehead's and Katkin's. Subjects were 48 male undergraduates who performed both discrimination tasks and then were subjected to mental arithmetic stress. Results indicated that high cardiovascular reactors were better detectors than low reactors. Results also indicated that subjects performed better on the modified Whitehead task than on the modified Katkin task.  相似文献   
82.
This study provides the first psychophysiological analysis of narcissism by measuring autonomic responses during active and passive anticipatory coping in 40 undergraduate men who scored high or low on the Narcissistic Personality Inventory (NPI). Compared to the low NPI group, the high NPI group showed greater preejection period (PEP) shortening, cardiac deceleration, and skin conductance response (SCR) habituation during anticipation of an aversive stimulus (p < .02). As expected, SCR and PEP reactivity were greater during active than passive coping. In the case of PEP, this effect emerged only in the low NPI group; the high NPI group showed the greatest PEP reactivity during the first task, regardless of coping demands. These data support hypothesized relationships among narcissism, psychopathy, and psychological predictors of cardiovascular disease, and suggest that a psychobiological dimension may underlie important features of narcissism.  相似文献   
83.
We examined putative autonomic and hemodynamic mechanisms that might explain our prior finding that cardiorespiratory fitness mitigates blood pressure responses by normotensive women during the hand cold pressor test. We report that fitness level was inversely related to increases in systolic and diastolic blood pressures and muscle sympathetic nerve activity (MSNA) during the cold pressor among women but not men. The pattern of responses among fitter women was consistent with decreased central sympathetic outflow resulting in reduced stroke volume or dampened peripheral resistance in vascular beds other than calf skeletal muscle. Fitter men and women had slightly larger increases in blood pressure during mental arithmetic, but otherwise fitness was not directly related to stress responses. The results further encourage consideration of cardiorespiratory fitness as a modifying covariate when the hand cold pressor test is used as a predictor of future hypertension among women.  相似文献   
84.
采用流式细胞术对42例正常晚孕妇女及50例妊高征患者产前及产后72小时P-选择素进行对比研究。结果:妊高征患者P-选择素含量明显大于正常晚孕妇女,P-选择素含量在轻、中及重度妊高征患者呈递增趋势,差异均有显著性,产后72小时其P-选择素含量降至正常晚孕妇女水平。提示:P-选择素可作为妊高征早期诊断及监测病情的一个重要指标  相似文献   
85.
Summary To study reflex responses caused by stimulation of pulmonary C-fibers and lung inflation, we used a preparation in which the left pulmonary artery and veins were ligated and cannulated and the right and left bronchi were cannulated separately in open-chest dogs. These experiments were performed to establish whether the reflex responses to injections of 150 g of capsaicin through the left pulmonary circulation and inflations of this left lung to 30 cm H2O would be diminished if repeated frequently. Furthermore, the sensitivities of the reflex responses evoked by these capsaicin injections and by left lung inflations (LLI) to blockade with lidocaine or with morphine were studied. Both repeated injections of capsaicin into the left pulmonary circulation and repeated inflations of the left lung for up to 100 min produced a persistent triad of reflex responses: bradycardia, hypotension, and cessation of diaphragmatic contractions. Lidocaine injections (50 mg) into the pulmonary artery of the vascularly isolated lung abolished all reflex responses to subsequent injections of capsaicin, but only attenuated the triad of responses to subsequent left lung inflations by half. Morphine sulfate (60 mg) administered to the pulmonary vascular bed of the isolated lung reduced, but did not eliminate, the triad of reflex responses to subsequent capsaicin injections and lung inflations. The influences of morphine upon capsaicin and lung inflation responses were not abolished by naloxone. These results indicate: (a) the sensory fibers which initiate the triad of pulmonary depressor reflex responses are not desensitized by repeated exposure to capsaicin or by repeated lung inflations; (b) sensory fibers other than pulmonary C-fiber receptors contribute to the lung inflation reflex; and (c) morphine and lidocaine interfere with the excitation of pulmonary C-fibers.  相似文献   
86.
Summary Additional experimental evidence was obtained for an inhibitory function of prejunctional 2-adrenoceptors and/or dopamine receptors located on noradrenergic neurons innervating the heart and resistance vessels of the pithed normotensive rat. Mixed 2-adrenoceptor receptor agonists, differing in selectivity towards either receptor type, i.e. N,N-di-n-propyldopamine (DPDA), 2-N, N-di-n-propylamino-6, 7-dihydroxy-1,2,3,4-tetrahydronaphthalene (DP-6,7-ADTN), B-HT 920 and B-HT 933 (azepexole) were used.In pithed normotensive rats, DPDA (30 and 100 g/kg/min) dose-dependently inhibited the electrical stimulation-induced increase in diastolic pressure, but did not significantly affect the stimulation-evoked increase in heart rate. The inhibition exerted by DPDA was blocked by haloperidol and sulpiride (0.3 mg/kg of each), but not by yohimbine (1 mg/kg), indicating the involvement of dopamine receptors. In this respect, sulpiride and haloperidol were found approximately equipotent.DP-6,7-ADTN (10 and 30 g/kg/min) impaired both tachycardic and vasoconstrictor responses in a dose-dependent manner. Sulpiride (0.3 mg/kg) only partially restored the DP-6,7-ADTN-depressed stimulation-evoked increase in diastolic pressure, whereas yohimbine (1 mg/kg) alone was without effect. The combination of both antagonists completely prevented the inhibition caused by DP-6,7-ADTN. On the other hand, yohimbine (1 mg/kg), but not sulpiride (0.3 mg/kg), selectively antagonized the DP-6,7-ADTN-induced inhibition of stimulation-evoked tachycardia.B-HT 920 (1, 3 and 10 g/kg/min) very effectively reduced the increase in diastolic pressure and heart rate caused by electrical stimulation. Inhibitory dopamine as well as 2-adrenoceptors participated in the vascular effects of B-HT 920, whereas 2-adrenoceptors were only involved in the cardioinhibitory response to this agonist.B-HT 933 (0.6 and 1 mg/kg/min) dose-dependently reduced the stimulation-evoked increase in arterial pressure through selective stimulation of inhibitory 2-adrenoceptors, dopamine receptors not taking a part.The results confirm and extend the observations that in addition to 2-adrenoceptors inhibitory dopamine receptors are located on the sympathetic neurons connected with the arterial vasculature of the pithed normotensive rat. The sympathetic nerves innervating the rat heart do not contain inhibitory dopamine receptors; their activity only can be modulated by 2-adrenoceptor stimulation. In the pithed normotensive rat, activation of prejunctionally located 2-adrenoceptors more effectively inhibits the sympathetic activity directed to the heart than that to the resistance vessels.  相似文献   
87.
目的 分析按病种分值付费政策对心血管病种患者实施效果并提供相关建议。方法 以广东省某大型三甲综合医院DIP政策实施前后收治的64 970份心血管病种患者为研究样本,通过描述性统计和双重差分法,分析两种不同医保支付方式(广州医保、其他医保)对相关医疗指标的影响。结果 按病种分值付费政策实施后,广州医保患者人均住院费用从49 060.62元下降到46 984.24元(t=-6.924,P<0.001),自负金额减少2 104.67元(t=-10.654,P<0.001),住院天数下降0.40天(t=-8.824,P<0.001),三个指标的差异均具有统计学意义,而其他医保支付方式患者的这三个指标在两个时期的差异无统计学意义。在费用结构中有明显变化幅度的分别是综合医疗服务费(t=53.403,P<0.001)、诊断费(t=50.198,P<0.001)、治疗费(t=22.804,P<0.001)、西药费(t=-12.488,P<0.001)、血浆和血浆制品费(t=-7.93,P<0.001)、耗材费(t=-17.901,P<0.001)以及其他费用(t=-115.076,P<0.001),差异均具有统计学意义,变化幅度最大的是耗材费,同比减少5.53%。以“风险级别”为分层标准对人均住院费用和住院天数进行双重差分法分层分析,政策效果仅发生在人均住院天数中“中低风险级别”和“没有出现死亡病例”两组病例。结论 按病种分值付费改革有利于增强医院自主管理意识,减轻参保人员个人负担水平,优化费用结构,但仍需加强控制重点费用类别,并未能充分体现医疗服务价值和达到促进分级诊疗目的,需提高支付标准的科学性和精准性。  相似文献   
88.
BackgroundThe healthy eating index-2015 (HEI-2015) reflects diet quality in reference to the 2015-2020 Dietary Guidelines for Americans (DGA). Little is known regarding its application in individuals with chronic spinal cord injury (SCI).ObjectiveTo explore the relationship between diet quality as assessed by the HEI-2015 and cardiovascular risk factors among individuals with chronic SCI.DesignThis is a cross-sectional analysis of baseline data collected from August 2017 through November 2019 for an interventional study that evaluates the effects of a high-protein/low-carbohydrate diet on cardiovascular risk factors in individuals with chronic SCI at the University of Alabama at Birmingham.Participants/settingTwenty-four free-living adults with SCI (mean age, 45 ± 12 y; 8F/16M, level of injury: nine cervical, 15 thoracic; mean duration of injury: 20 ± 13 y) were included.Main outcome measuresParticipants underwent a 2-hour oral glucose tolerance test (OGTT) and a dual-energy x-ray absorptiometry scan. Dietary intake was assessed by three, 24-hour multiple-pass dietary recalls to calculate the HEI-2015 using the simple HEI scoring algorithm method.Data analysisMultiple linear regression analyses were performed to predict indices of lipid metabolism and glucose homeostasis and C-reactive protein (CRP) from the HEI-2015. Principal component analysis was used to reduce the number of covariates (level of injury, sex, and body fat percentage).ResultsOn average, participants’ diets were of low quality (HEI-2015, 47.2 ± 10.8). The regression models for fasting glucose (FG), cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and CRP had moderate to large effect sizes (adjusted R2 ≥ 13%), suggesting good explanatory abilities of the predictors. Small or limited effect sizes were observed for glucose tolerance, fasting insulin, triglycerides, and Matsuda index (adjusted R2 < 13%). The HEI-2015 accounted for a moderate amount of variation in FG (partial omega-squared, ωP2 = 13%). Each 10-point HEI-2015 score increase was associated with a 3.3-mg/dL decrease in FG concentrations. The HEI-2015 accounted for a limited amount of variation in other indices (ωP2 < 5%).ConclusionsAmong participants with SCI, higher conformance to the 2015-2020 DGA was 1) moderately associated with better FG homeostasis; and 2) trivially associated with other cardiovascular risk factors. Because of the small sample size, these conclusions cannot be extrapolated beyond the study sample. Future larger studies are warranted to better understand the relationship between diet quality and cardiovascular disease risks in this population.  相似文献   
89.
Cardiovascular disease (CVD) has become one of the commonest causes of comorbidity and mortality among People living with human immunodeficiency virus (HIV) (PLWH) on antiretroviral therapy (ART). Nearly 50% of PLWH are likely to have an increased risk of developing CVD, including coronary heart disease, cerebrovascular disease, peripheral artery disease and aortic atherosclerosis. Aside from the common risk factors, HIV infection itself and side effects of antiretroviral therapy contribute to the pathophysiology of this entity. Potential non-pharmacological therapies are currently being tested worldwide for this purpose, including eating patterns such as Intermittent fasting (IF). IF is a widespread practice gaining high level of interest in the scientific community due to its potential benefits such as improvement in serum lipids and lipoproteins, blood pressure (BP), platelet-derived growth factor AB, systemic inflammation, and carotid artery intima-media thickness among others cardiovascular benefits. This review will focus on exploring the potential role of intermittent fasting as a non-pharmacological and cost-effective strategy in decreasing the burden of cardiovascular diseases among HIV patients on ART due to its intrinsic properties improving the main cardiovascular risk factors and modulating inflammatory pathways related to endothelial dysfunction, lipid peroxidation and aging. Intermittent fasting regimens need to be tested in clinical trials as an important, cost-effective, and revolutionary coadjutant of ART in the fight against the increased prevalence of cardiovascular disease in PLWH.  相似文献   
90.
目的 分析心血管疾病住院患者疾病谱及住院费用,了解疾病构成的规律特点及经济负担,为心内科疾病诊治工作提供参考依据。方法 回顾性分析攀枝花市某三级医院2017—2019年心血管疾病住院患者资料,从医院相关管理信息系统中导出诊断为心血管疾病的病例条目、详细病历及病例住院费用等数据,采用描述流行病学分析方法对心血管疾病住院患者资料进行分析。结果 共纳入心血管疾病住院患者11 376例,2017—2019年分别有3 492、3 815、4 069例,分别占30.7%、33.5%、35.8%,病例数逐年上升。3年间心血管疾病住院患者的性别分布差异无统计学意义(P>0.05),年龄分布差异有统计学意义(P<0.01),心血管疾病住院患者发病呈年轻化趋势。病种均以冠心病和高血压所占比例最大,合计分别占当年心血管疾病住院患者的57.6%、55.5%,2019年则上升至62.8%。3年间心血管疾病住院患者有伴发疾病比例(27.6%、26.1%、25.4%)差异无统计学意义(P>0.05)。心血管疾病住院患者住院天数分布差异有统计学意义(P<0.01),2019年的患者住院时间<7 d的比例有所上升。2017、2018、2019年该医院心血管疾病住院患者诊治自费费用分别为(5 925.6±285.7)、(5 904.2±264.3)、(5 890.9±230.8)元/人,差异有统计学意义(P<0.01)。结论 2017—2019年攀枝花市某医院心血管疾病住院患者病例数增加,住院患者发病年龄有年轻化趋势,主要病种仍以冠心病和高血压为主,住院天数及自费费用呈下降趋势。  相似文献   
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