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61.
A large body of work relating to the occurrence of rickets in UK Asians is reviewed. Several theories of the aetiology of this condition are shown to be untenable: it is not exclusively a function of sunlight deprivation or of darker pigmentation; nor is it simply due to phytate-induced losses of calcium from the gut. Asian rickets, however, is associated with a high consumption of cereals, and experiments with rats have suggested a mechanism. In the absence of adequate vitamin D from sunlight, the low-calcium, high cereal intake of the UK Asian population may induce a state of mild secondary hyperparathyroidism which enhances the destruction of vitamin D and leads to a progressive reduction in vitamin D status and, ultimately, to the development of clinical rickets.  相似文献   
62.
Background: Multiple factors related to specific dimensions of health – general, physical and mental – contribute to mortality in the elderly, but their relative contributions to mortality risk is not well‐known. The objectives of this prospective population‐based cohort study were to measure mortality rates and to identify predictors of mortality in community‐dwelling men and women aged 65 years or older in Korea by examining self assessments of general health, objective medical burden, and measurement of cognition, mood and function. Methods: A total of 1245 elderly (529 men; 716 women) were followed up longitudinally for 3.5 years. Fixed predictor variables observed at baseline examined in Cox proportional hazards models were age, sex, education, chronic medical illnesses, self‐rated health, basic activities of daily living, depression measured by the Geriatric Depression Scale, and cognition measured by the Mini‐Mental State Examination. Results: Mortality rates were similar to those of the 2001 Korean population. Older age, male sex, poor self‐rated health and presence of cerebrovascular disease were significant predictors of mortality. Presence of ischemic heart disease and cerebrovascular disease at baseline predicted mortality in men, but not in women. Depression predicted mortality only when chronic medical illnesses were excluded from the model. Conclusions: Subjective self‐rated health and objective medical burden are strong independent predictors of mortality in this elderly community population, in addition to age and sex.  相似文献   
63.
目的对二氧化碳吸入、屏气及过度换气等3种不同的脑血管反应性检测方法进行比较,拟为临床应用探索一种有效且简便的方法。方法70例健康体格检查者通过经颅多普勒(TCD)超声技术常规检测颅底及颈部各动脉,然后分别进行二氧化碳吸入试验、过度换气试验和屏气试验,记录试验前后双侧大脑中动脉血流速度变化数据和趋势,检测脑血管反应性。结果吸入二氧化碳后,大脑中动脉平均血流速度明显加快,增加率为(44.86±10.18)%;过度换气时,平均血流速度明显减慢,于过度换气20~30s后降至平台期,平均下降率为(33.63±8.62)%,直至过度通气结束血流速度无明显变化。70例受试者平均屏气时间为(41.66±9.51)s,其中男性屏气时间(42.05±9.23)s,女性(40.63±10.47)s,男女之间差异无统计学意义(P>0.05);屏气后大脑中动脉平均血流速度明显加快,增加率为(46.53±11.83)%;平均屏气指数为1.16±0.37;屏气后血流速度增加率和屏气指数之间呈高度正相关(r=0.865,P<0.01);当屏气时间>30s时,无论采用屏气后血流速度增加率或屏气指数作为分析指标,均可准确地反映脑血管反应性变化。对二氧化碳吸入试验、过度换气试验及屏气试验3种不同方法进行比较显示,过度换气试验与二氧化碳吸入试验、屏气试验间差异有统计学意义(P<0.01);而二氧化碳吸入试验与屏气试验之间差异无统计学意义(P>0.05)。结论二氧化碳吸入试验、屏气试验和过度换气试验均可有效地评价脑血管反应性,其中以屏气试验评价脑血管反应性更为简便。  相似文献   
64.
65.
The effects of zymosan-activated plasma(ZAP)on lung fluid exchangeand on superoxide anion production by granulocytes were studied in 8 consciousgoats with chronic lung lymph fistula,It was found that after ZAP infusion, thecirculating granulocytes were activated and the release of superoxide anions wasmarkedly enhanced. There was an increase in lung lymph flow and proteinconcentration.It suggests that the superoxide anion released by the stimulatedgranulocytes can play a role in inducing lung injury by the activated complement.  相似文献   
66.
Our experience in using biplane transesophageal echocardiography in the assessment of coarctation of the aorta is described.  相似文献   
67.
ABSTRACT This paper describes further testing of an Activity Index introduced by Hamrin & Wohlin, which was designed especially to evaluate the functional capacity of patients after stroke. The results of reliability tests and validation procedures are presented, in particular in comparison with the internationally well known Katz Index of Independence in Activities of Daily Living. The standardised item alpha reliability coefficient for the Activity Index was 0.97 for the total score (n= 231) and the corresponding value for the Katz Index of ADL was 0.94. Using factor analysis with four factors, 88.3% of the variances of the 16 variables of the Activity Index could be explained, and the different variables were found to have a logical distribution between the factors. In a two-factor analysis of the Katz Index of ADL, 89.6% of the variance of the six variables could be explained, and the hierarchical structure of the test was recognised. Compared with the Katz Index of ADL, the Activity Index had a higher predictive capacity and it also better measured changes in the patient's functional ability between different test occasions.  相似文献   
68.
OBJECTIVES: Clinical trials and community-based studies often include the Center for Epidemiologic Studies-Depression scale (CES-D) as a measure of depression outcome. We compared responses to symptom-related items on the CES-D by depressed stroke and primary-care patients for several purposes: 1) to illustrate the use of Item Response Theory (IRT)-based (Rasch) models for comparing scale functioning across different patient subgroups; and 2) to inform clinicians and outcome researchers about scale functioning and depressive symptomatology in stroke- compared with primary care-based depression. METHODS: Two data sources were analyzed, including 32 depressed patients who were 3 months poststroke, and 366 depressed primary-care patients. Presence of depression was based on a CES-D score 16 or higher. Rasch models were used to assess item fit and compare item hierarchies between depressed primary-care and stroke patients. RESULTS: Item hierarchies were similar for poststroke depression and primary care-based depression. Interpersonal disruption items were the most difficult to endorse for both groups. No items misfit the scale in primary-care depression. Items relating to restless sleep, unfriendliness, and crying slightly misfit the scale in stroke patients, that is, may measure a different trait. Differential item functioning (DIF) between the groups was identified for items relating to appetite, restless sleep, crying, and feeling disliked. CONCLUSIONS: Results generally supported the use of the CES-D as measure of depression outcome, particularly in primary care-based depression. DIF may imply that slightly different clusters of depressive symptoms are reported by depressed stroke patients compared with primary care, but this is conjectural given the small stroke sample size and the same items have been previously associated with bias in studies of large nonstroke samples. This study found Rasch models to be useful tools to investigate scale performance for different clinical applications.  相似文献   
69.
川芎对脑血管血液动力学参数作用的实验研究   总被引:12,自引:0,他引:12       下载免费PDF全文
我们用食饵性高血脂加异种血清反复静脉注射造成动脉内皮免疫性损伤的方法,建立了兔实验性动脉粥样硬化模型,观察了中药川芎对脑血管血液动力学参数(CVHP)的影响。发现川芎组CVHP各项指标均与正常对照组接近,与正常组比较,无显著性差异,颈动脉平均血流量(Qmean)、平均血流速度(Vmean)、最小血流速度(Vmin)、脑血管零压顺应性(CO)和脑血管外周阻力(R)等指标显著优于动脉粥样硬化组(P<0.05~0.01)。本实验结果提示川芎对脑血管功能具有保护作用。  相似文献   
70.
目的探讨常温及低温体外循环心脏直视手术对细胞因子及补体的影响。方法选择先天性和风湿性心脏病患者40例,随机分为常温组及低温组各20例,分别于术晨、体外循环结束时及术后1、4、7、14 d抽取患者静脉血标本,测定血浆TNF、IL-2、C3、C4值。结果两组术前各项检查指标无显著差异。(1)两组术后1~4 d的IL-2水平较术前显著下降,至术后7 d恢复正常。体外循环结束至术后4 d,低温组IL-2显著低于常温组。(2)体外循环结束时以及术后1、4、7 d,常温组TNF水平显著低于低温组。两组体外循环结束时及术后1、4 d均高于术前,常温组至术后7 d、低温组术后14 d恢复正常。(3)体外循环结束时及术后1、7 d,常温组C3水平高于低温组,术后4 d两组无差别;常温组及低温组于体外循环结束时、术后1、4 d均低于术前,至术后7 d常温组恢复正常,低温组至术后14 d恢复至术前水平。(4)两组体外循环结束时及术后1、4 d C4水平均低于术前。体外循环结束时、术后1 d,常温组C4水平高于低温组。结论常温体外循环心脏直视手术对细胞因子及补体的影响显著轻于低温组,因而对术后机体的恢复优于低温方法。  相似文献   
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