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101.
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Anatomic and physiologic evaluation of upper extremity ischemia.   总被引:1,自引:0,他引:1  
This study assessed the accuracy of arteriography and laser Doppler perfusion imaging (LDPI) as predictors of digital ischemia and correlated upper extremity symptoms, function, and nutritional flow with arteriographic and laser Doppler assessments. Multiple-level occlusive disease was documented in 25 hands (23 patients) by arteriography. LDPI demonstrated one or more hypoperfused digits in 17 hands. Patient questionnaires were used to assess upper extremity symptoms, pain, cold sensitivity, and function. Spearman correlation coefficients indicated that arteriography is a poor indicator of nutritional perfusion as measured by LDPI. Neither arteriography or laser Doppler perfusion imaging served as an indicator of the severity of cold intolerance. However, upper extremity symptoms and functional status correlated with both laser Doppler measurements and the level of cold sensitivity. Laser Doppler perfusion imaging and arteriographic analysis provide complimentary data in the evaluation of upper extremity ischemia.  相似文献   
104.
目的探讨呼吸重症监护病房(respiratoryintensivecareunit,RICU)中患者出现谵妄的病因。方法对2010—06/2012—06月在作者医院RICU住院期间出现谵妄的患者进行回顾性分析,同期随机抽取相同例数未出现谵妄的患者作为对照组,进行比较分析。结果住院期间出现谵妄的患者共30例,发生率为8.2%(30/362),年龄多在70岁以上,男女无明显差异。南原发病引起的谵妄占53.3%(16/30),其中以肺部感染、慢性阻塞性肺疾病、呼吸衰竭、心力衰竭多见,40%患者需要机械通气。药物因素引起的谵妄占33.3%(10/30),以喹诺酮类、糖皮质激素类、茶碱类药物多见。由个人因素和ICU环境因素引起的谵妄占13.3%(4/30)。与对照组比较,谵妄组病死率无明显增加,但住院时间长[(16±5)d vs.(12±4)d,P〈0.05],住院费用高。结论通过积极处理原发病,去除诱因及有针对性地对患者进行心理疏导,有助于降低RICU谵妄发生率。  相似文献   
105.

Background  

The current study investigated the repeatability (test-retest reliability) of ground reaction force parameters recorded during a voluntary step execution under single (motor task) and dual task (motor and cognitive task) conditions for healthy adults and elderly individuals as well as the number of trials required to produce repeatable results.  相似文献   
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To date, more than 100 point mutations and several hundreds of structural rearrangements of mitochondrial DNA (mtDNA) are known too be connected with characteristic neuromuscular and other mitochondrial syndromes varying from those causing death at the neonatal stage to diseases with late ages of onset. The immediate cause of mitochondrial disorders is a defective oxidative phosphorylation. Wide phenotypic variation and the heteroplasmy phenomenon, which some authors include in mutation load, are characteristic of human mitochondrial diseases. As the numbers of cases identified and pedigrees described increase, data on the genotype-phenotype interaction and the structure and frequency of pathogenic and conditionally pathogenic mtDNA mutations in human populations are rapidly accumulated. The data on the genetics and epidemiology of mitochondrial diseases are not only important for differential diagnosis and genetic counseling. Since both neutral and mildly pathogenic mutations of mtDNA are progressively accumulated in maternal phyletic lines, molecular analysis of these mutations permits not only reconstruction of the genealogical tree of modern humans, but also estimation of the role that these mutations play in natural selection.  相似文献   
108.
Fenech  MF; Dreosti  IE; Rinaldi  JR 《Carcinogenesis》1997,18(7):1329-1336
Deficient levels of folic acid and vitamin B12 are associated with elevated chromosome damage rate and high concentrations of homocysteine in the blood. We have therefore performed a study to determine the prevalence of folate deficiency, vitamin B12 deficiency and hyperhomocysteinemia in 64 healthy men aged between 50 and 70 years, and evaluate the relationship of these micronutrient levels in the blood with the micronucleus frequency in peripheral blood lymphocytes. We also performed a placebo-controlled, double-blind intervention study to determine whether supplementation of the diet with a daily dose of 0.7 mg (as a supplement in cereal) or 2.0 mg (in a tablet) over a period of 4 months resulted in a significant alteration of folate status, homocysteine status and the micronucleus index. Twenty-three per cent of the men were serum folate deficient (<6.8 nmol/l), 16% were red blood cell folate deficient (<317 nmol/l), 4.7% were vitamin B12 deficient (<150 pmol/l) and 37% has plasma homocysteine levels >10 micromol/l. In total, 56% of the men had one or more abnormal blood values for folate, vitamin B12 or homocysteine. The micronucleus index of these men (n = 34) in cytokinesis-blocked binucleated cells (19.2 +/- 1.1) was significantly elevated (P = 0.02) when compared to the micronucleus index of the rest of the men who had normal levels of folate, vitamin B12 and homocysteine (16.3 +/- 1.3, n = 30). Interestingly, the micronucleus index in men with normal folate and vitamin B12, but homocysteine levels >10 micromol/l (19.4 +/- 1.7, n = 15) was also significantly higher (P = 0.05) when compared to those with normal folate, vitamin B12 and homocysteine. This novel result was also supported by the observation that the micronucleus index and plasma homocysteine were significantly (P = 0.0086) and positively correlated (r2 = 0.172) in those subjects who were not deficient in folate or vitamin B12. The micronucleus index was not significantly correlated with folate indices, but there was a significant (P = 0.013) negative correlation with serum vitamin B12 (r2 = 0.099). Daily supplementation of the diet with 0.7 mg free folic acid in cereal for 2 months followed by 2.0 mg free folic acid via a tablet produced a 4- fold increase in plasma folate, a 2.6-fold increase in red blood cell folate and a 11% reduction in plasma homocysteine; however, these changes were not accompanied by a reduction in the micronucleus index. In conclusion, it is apparent that elevated homocysteine status, in the absence of vitamin deficiency and low, but not deficient, vitamin B12 status are important risk factors for increased chromosome damage in lymphocytes.   相似文献   
109.
A rabbit ear model resembling the human digit was studied to determine the vascular response of the rabbit ear to a cold stress. Following moderate cooling (10 minutes at 5°–8°C), auricular blood flow and cutaneous perfusion were reduced. This decrease was reversed by 30 minutes of warming. The response in the rabbit ear to cold stress is similar to that of normal human digits. The similarities between the control of the circulation in human digits and rabbit ears may result from the similarities in digital and auricular vascular receptors and receptor subtypes. Verification of the rabbit model provides an experimental method for obtaining important data regarding digital pathophysiology and the treatment of cold intolerance. Further study with this model will provide clinically relevant information regarding the pathophysiology of digital thermoregulatory abnormalities. © 1994 Wiley-Liss, Inc.  相似文献   
110.
A hypermobile hyperextension or hyperflexion deformity of the metacarpophalangeal (MCP) joint associated with thumb-in-palm deformity in 90 patients affected by cerebral palsy was treated by arthrodesis with or without soft-tissue procedures. Twenty-two of these patients were adults with closed physes, and 68 were children or adolescents with open growth plates. The MCP joint fusion was usually accompanied by intrinsic muscle lengthening and/or extrinsic tendon transfer, but occasionally it was the only procedure performed to diminish the thumb-in-palm position. Even in four-year-olds, joint fusion was a predictable procedure to establish stability of that joint without disturbing longitudinal or circumferential growth. Measurable function was improved to a mild or moderate degree in 44 of the 50 children who were followed to maturity. Eighteen of the 68 children were unavailable for follow-up evaluation. Six of the 50 followed patients showed no functional improvement, although arthrodesis of the MCP joint occurred in four of the six. The other two patients were operated on when they were 12 years of age and developed a fibrous union that was painless and stable when they were adults. Even those patients who had no functional improvement did have improved appearance and easier control of the affected hand when it was manipulated by the opposite hand. The children were followed to maturity with age-matched cerebral palsy control patients. There was no significant disturbance in growth of those thumbs that had MCP joint fusion when the physes were open.  相似文献   
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