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81.
模拟股骨置入人工关节扭转与应力松弛蠕变的实验研究   总被引:1,自引:0,他引:1  
研究了在相同扭矩作用下,正常组股骨和以生物学和骨水泥固定置入人工关节组股骨标本扭转角度,还对正常股骨、生物学固定股骨和骨水泥固定股骨进行应力松弛、蠕变实验,为临床提供生物力学参数。以电子万能试验机对正常对照组、股骨置入人工关节骨水泥固定组、股骨置入人工关节生物学固定组标本进行扭转和粘弹性实验研究。得出了各组标本在相同扭矩下的扭转角度及悬臂弯曲状态下,正常组和置入人工关节组标本应力松弛、蠕变数据和曲线。对实验数据进行归一化处理,得出了正常组和置入人工关节组标本的归一化应力松弛函数,归一化蠕变函数及曲线。表明:骨水泥固定组扭转角比生物学固定组小,说明骨水泥固定有较好的稳定性,其应力松弛、蠕变量丢失小。骨水泥固定组较生物学固定组3600s应力松弛、蠕变量大。  相似文献   
82.
The predictability of individual differences in activation processes was investigated in a multi-method laboratory-field study. Male students of physical education (N=58) were examined under various emotionally activating and physically demanding conditions (mental arithmetic, reaction time, free speech, cold pressor test, bicycle ergometer). The assessment included multi-channel recordings of pre-start phases in an athletic stadium and performance on a 1000 m run. Basal heart rate was also recorded during sleep. This multi-situational assessment was repeated after three weeks, three months, and, for most (N=42) subjects, after one year. Significant relationships exist between scores from corresponding conditions of relaxation, anticipation, and performance of physical exercise. However, with the exception of heart rate, correlation coefficients are rather small and seem to be of questionable predictive validity. A generalizability study further supports the general conclusion: To increase the practical relevance in psychophysiological investigations of stress/strain phenomena, such studies should directly assess individual differences in the criterion situations themselves.  相似文献   
83.
Summary The flux rates of plasma glucose and alanine were studied isotopically (6-3H-glucose and U-14C-alanine simultaneously) in resting chronically diabetic dogs during short-term treatment with an artificial B cell where the insulin was infused into a peripheral vein. Despite perfect blood glucose control and normal glucose flux rates, the concentration and rates of appearance and disappearance of alanine were significantly elevated in the diabetic animals before, during and after an exogenous glucose load. The incorporation of the carbon moiety of alanine into circulating glucose was also increased, but diminished to a near-normal extent when exogenous glucose was given. The plasma clearance rates for alanine in the diabetic dogs were normal throughout the study. It is concluded that normal blood glucose control in diabetes does not necessarily mean normalization of the entire metabolic network. On the basis of peripheral hyperinsulinaemia alanine formation from glucose and branched chain amino acids is elevated in muscle. This may explain increased flux of alanine despite normal blood glucose control.  相似文献   
84.
A nation-wide cohort of 12,737 first admitted patients aged 15 years or more to Danish psychiatric institutions was followed in the Danish Case Register for a 10-year period. Long stay patients were delineated as: 1) patients whose first admission lasted for more than 1 year (new long-stay); or 2) patients who later had an admission lasting for more than 1 year (late long-stay). Together they comprised 420 males and 527 females with an incidence rate of 0.22 males and 0.27 females per 1,000. Up to age 65 males dominated, after 65 females dominated. Thirty-three percent of demential disordered and 24 of schizophrenics became long-stay patients. A multiple contingency analysis showed that the variables "age group", "main diagnosis", "size of municipality of residence" and "marital status" were independently associated with the outcome "long-stay". The two long-stay groups differed. New long-stay patients tended to be females, older, suffering from demential disorders and with a total hospital stay shorter than that of the long-stay population. In a multiple contingency analysis the variables "age group" and "main diagnosis" were independently associated with the outcome "new long-stay" and the variables "age groups", "main diagnosis" and "size of municipality of residence" with the outcome "late long-stay".  相似文献   
85.
Pulmonary hypertension (PH) produces strain followed by hypertrophy and later dilatation of the right ventricle (RV) and pulmonary artery. The signs and symptoms are nonspecific. There is a need for a noninvasive sensitive way to diagnose PH. The purpose of this study is to evaluate phase abnormalities in radionuclide MUGA studies of patients with referred diagnosis of PH. In a retrospective analysis of 44 patients who had a radionuclide multigated study (MUGA) and contrast ventriculography (CV), 19 had high mean pulmonary pressure (over 20 mmHg) and a high pulmonary vascular resistance index (over 2.0). In 15 patients, a delayed phase segment in the RV corresponding to the pulmonary infundibulum and pulmonary conus was noted The Pulmonary Tongue sign (PT), 12 had PH (True positive) and 3 did not (false positive) on CV. No PT was seen in the remaining 29 patients, only 7 of them had PH (False negative). The sensitivity, specificity and accuracy of the PT sign in detecting PH was 80%, 72% and 77% respectively. The number of patients was too small to calculate the correlation of the grade of PT with the severity of PH. We conclude that The Pulmonary Tongue sign on a MUGA study is clinically useful in detecting PH.This project is supported by research project MLNO13 and funded by research Council, Kuwait University  相似文献   
86.
Summary Clinically relevant events possibly attributable to drug exposure have been monitored prospectively over a period of six months in 27 general intensive care units. Fifty-four events attributed to drugs were reported in 51 patients during their stay in hospital, corresponding to an overall incidence of 1.35%. The behaviour of the physicians following attribution of the events to a prescribed drug is analyzed and discussed in detail with respect to its relationship to the quality and severity of the reaction, and the classes of drugs. Twenty-four of the 4537 monitored admissions during the six months were due to life-threatening emergencies linked to the administration of drugs (14) and radio-contrast media (10) (overall incidence 0.5%). While the clinical burden attributable to adverse drug reactions in Intensive Care Units appears to be relatively small, the analysis shows that there is ample room for a greater reduction in their incidence. Coordinators: Drs M. L. Farina and G. Tognoni, Istituto di Ricerche Farmacologiche Mario Negri, Milan; Dr F. Procaccio, Neurosurgical ICU, Ospedale Ca' Granda, Niguarda, Milan.Investigators: Drs G. Barusco, Rovigo; F. Bassi, Milan; L. Bianchetti, Torino; E. Carchietti, Udine; G. Chilloni, Reggio Emilia; G. Costantini, Savigliano (CN); P. Ferrero, Aosta; E. Geat, Trento; F. Gorgerino, Torino; A. Lusini, Empoli (FI); G. Mantovani, Ferrara; S. Marchi, Bologna; P. Marcovigi, Forli; G. Marraro, Merate (CO); F. Merlo, Vicenza; E. Pagni, Bagno a Ripoli (FI); R. Pellegrino, Cuneo; C. Peruselli, Milan; A. Piovesano, Pordenone; R. Rinaldo, Cremona; R. Ruggerini, Piacenza; S. Sammartino, Torino; A. Sartore, Cittadella (PD); A. Scaglioli, Carpi (MO); G. Scopa, Terni; G. Zeffiro, Treviso; P. Zuccoli, Parma  相似文献   
87.
150 children with Rolandic paroxysmal epilepsy (RPE) aged 3 to 12 years were followed up clinically and by EEG for 16 years. Antiepileptic drugs were administered initially for 2 years and then suspended for 6–12 months. Treatment was resumed in the 29 patients who had seizures during the drug-free interval and was maintained for a further 5 years.80.6% of all patients were in clinical remission after the 2-year treatment period. Some patients had seizures while on drugs, others during the drug-free interval. Seizure frequency declined with age. No seizures occured after the age of 14 or in the 8 years following final discontinuation of drug therapy. The need for prolonged drug treatment is therefore questioned.
Sommario 150 bambini affetti da Epilessia a Parossismi Rolandici, di età compresa tra i 3 e i 12 anni, sono stati tenuti sotto controllo clinico ed elettroencefalografico per un periodo di sedici anni.È stato effettuato un trattamento con farmaci antiepilettici per 2 anni. Dopo 6/12 mesi di wash-out farmacologico, in 29 pazienti che hanno manifestato crisi, la terapia farmacologica è stata ripristinata e mantenuta per 5 anni.Dopo i primi due anni di terapia, si è avuta una remissione clinica nell'80.6% dei casi. Alcuni pazienti hanno manifestato crisi durante l'assunzione della terapia, altri durante il periodo di wash-out. In ogni caso l'incidenza delle crisi diminuisce con il crescere dell'età dei pazienti. Al di sopra dei 14 anni non sono state registrate crisi, e l'osservazione durante gli otto anni successivi alla sospensione definitiva della terapia farmacologica non ha rivelato la comparsa di alcuna crisi.Viene quindi discussa la necessità di un trattamento farmacologico prolungato in corso di Epilessia a Parossismi Rolandici.
  相似文献   
88.
Wide-field specular microscopy, slit-lamp examination, and pachometry were performed on 22 successful hard contact lens wearers and 22 controls matched for age, race, sex, and refractive error. A minimum of 600 cells per control and 1200 per contact lens wearer were manually digitized from the specular photomicrographs. Frequency distributions of cell areas were compared between the two groups using the parameters of mean, median, standard deviation, coefficient of variation, skewness and kurtosis. Slit-lamp examination was normal and there was no significant difference in corneal thickness between the patient group and the control group. Comparison of mean, median, and standard deviation also revealed no significant difference, but skewness (P less than .001), kurtosis (P less than .001) and coefficient of variation (P less than .004) were greater in the hard contact lens wear group. Hard contact lens wearing time correlated with increasing pleomorphism (P less than .05). Specular microscopy also revealed morphologic changes including deep stromal striae, intra- and extracellular "blackout" areas, and clustering of extremely small and large cells. The possible relationship between endothelial hypoxia and structural stromal changes are discussed.  相似文献   
89.
通络胶囊治疗偏头痛的临床与实验研究   总被引:2,自引:0,他引:2  
认为正气不足、病理体质为偏头痛的发病基础 ,以气血失调为主 ,寒热虚实错杂是本病的基本病机。据此确立扶正固本、祛风活络、化瘀止痛的治疗原则 ,拟通络胶囊治疗偏头痛 30例 ,与太极通天液治疗 30例对照 ,结果表明 ,治疗组愈显率 83.33% ,总有效率 93.33% ,与对照组相比有显著性差别 (P<0 .0 1) ,在改善兼症方面亦优于对照组 (P<0 .0 5或 P<0 .0 1) ,并能改善患者颅内血管功能状态。动物实验表明 ,通络胶囊能提高实验动物痛阈 ,同时提高大鼠下丘脑 5 - HT及 β-内啡呔水平 ,并能改善大鼠软脑膜微循环。  相似文献   
90.
细胞因子在清肝化瘀汤治疗慢性粒细胞性白血病中的研究   总被引:1,自引:0,他引:1  
邱仲川  徐旻 《上海医学》2001,24(3):161-162,155
目的观察中药清肝化瘀汤治疗慢性粒细胞性白血病(慢性期)的疗效,并探讨细胞因子水平变化的意义。方法收集45例慢性粒细胞性白血病慢性期患者(治疗组),用清肝化瘀汤治疗,观察患者的临床疗效、细胞因子水平。另用20名正常人作为对照(对照组)。结果治疗组完全缓解率40%,部分缓解率46.7%,总有效率86.7%。治疗组细胞因子水平中白介素2、可溶性白介素2受体、肿瘤坏死因子a治疗前后有显著差异(P<0.05);干扰素γ水平变化无显著差异。且与正常对照组比较无显著差异(P>0.05)。结论清肝化瘀汤有清热泻肝解毒、活血化瘀消癥的功效,研究结果显示,该药对慢性粒细胞性白血病慢性期(肝热血瘀型)疗效确切,其作用机理可能与改善细胞因子水平有关。  相似文献   
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