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71.
Hyland K  Arnold LA 《Journal of child neurology》2002,17(Z3):3S48-55; discussion 3S56
Seizures are one of the most frequently occurring neurologic phenomena in childhood; an inborn error of metabolism should always be considered in the diagnostic workup of patients with seizures after more common causes have been excluded. Many of the known inborn metabolic errors associated with seizures can be detected by metabolite measurement in urine or blood. It is now recognized, however, that there are several conditions in which peripheral metabolite profiles remain normal. Abnormal metabolism is indicated only by the accumulation or absence of specific metabolites within the central nervous system. Some of these disorders can be detected by in vivo magnetic resonance spectroscopy. More often, an etiology can be ascertained only by analysis of specific metabolites in cerebrospinal fluid. This review describes the utility of cerebrospinal fluid metabolite analysis in the differential diagnosis of inborn errors of metabolism that lead to infantile epilepsy. These include disorders of central nervous system energy metabolism, creatine synthesis and transport, serine biosynthesis, and glucose transport, together with defects affecting the gamma-aminobutyric acid (GABA), catecholamine, and serotonin neurotransmitter systems. In addition, information is provided regarding detection of an early-onset seizure disorder that responds to folinic acid.  相似文献   
72.
Aromatic L-amino acid decarboxylase (AADC) is a vitamin B 6 requiring enzyme involved in the biosynthesis of the neurotransmitters dopamine (DA) and serotonin. Lack of AADC leads to a combined deficiency of the catecholamines DA, norepinephrine (NE), epinephrine (E) as well as of serotonin. Here we describe premature twins who presented with severe seizures, myoclonus, rotatory eye movements and sudden clonic contractions. The patients showed an improvement of the clonic contractions under vitamin B 6 supplementation but died in the third week of life. In CSF and urine a biochemical pattern indicative of AADC deficiency was revealed. Concentrations of homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA) and 3-methoxy-4-hydroxyphenylglycol (MHPG) were decreased, in association with increased concentrations of 3-ortho-methyldopa (3-OMD) in CSF and significantly increased vanillactic acid in urine. The AADC enzyme substrates L-dopa and 5-hydroxytryptophan (5-HTP) were elevated in CSF. Elevated concentrations of threonine as well as of an unidentified compound in CSF rounded off the biochemical pattern. AADC activity was found to be increased in plasma and deficient in the liver. Molecular studies effectively ruled out a genetic defect in the AADC gene. The basis for the epileptic encephalopathy in the twins may be located in the metabolism of vitamin B 6 and remains to be defined.  相似文献   
73.
Aromatic L-amino acid decarboxylase (AADC - E.C. 4.1.1.28) converts L-dopa to dopamine and 5-hydroxytryptophan to serotonin. Inherited deficiency of this enzyme leads to decreased brain levels of these neurotransmitters. Clinically this results in the development of a progressive neurometabolic disorder characterized by severe hypotonia, dystonic and choreoathetoid movements, oculogyric crises, and hypothermia from infancy. Here we describe the clinical, biochemical and molecular details of two affected brothers, one of whom, despite the lack of AADC, presented with hyperdopaminuria. In addition, we detail his reactions to treatment with dopaminergic agonists, monoamine oxidase inhibitors and pyridoxine.  相似文献   
74.
In an effort footline to motivate smokers across New York State to stop smoking, tobacco control programs across the state held 'Quit and Win' incentive-based stop-smoking contests. These contests encouraged smokers to make a quit attempt by offering a chance to win cash prize (usually 1,000 dollars) for successfully stopping smoking for at least 1 month. Between 2001 and 2004, 11 different Quit and Win Contests involving 5,504 adult smokers were sponsored in different communities across New York State. Follow-up surveys were conducted 4 to 6 months after each contest ended to evaluate participants' success in quitting smoking. Expenditures for promoting contests varied from a high of 91,441 dollars to a low of 4,345 dollars, with a median of 25,928 dollars. An average of 0.55 percent of smokers was recruited to join contests across the 11 communities. Among smokers who enrolled in a contest, 9 out of 10 reported making a quit attempt, and between 53 percent and 72 percent reported quitting for the full month of the contest. At 4 to 6 months follow-up, self-reported quit rates (7-day point prevalence) among contestants ranged from 22 percent to 49 percent, with an average of 31 percent. Based on a statewide population survey, 8 of the 11 programs showed quit rates that were significantly higher (P < .001 by Wilcoxon rank-sum test) than the estimated quit rate of 21 percent seen among smokers making a quit attempt in the past year. This study shows that for a relatively modest investment of resources, thousands of smokers can be recruited to make a serious quit attempt, with many remaining smoke-free months later.  相似文献   
75.
血府逐瘀汤对乳鼠心肌细胞缺血再灌注损伤的影响   总被引:4,自引:0,他引:4  
目的为探讨血府逐瘀汤对乳鼠心肌细胞缺血再灌注损伤的影响。方法应用培养的乳鼠心肌细胞造成缺血再灌注损伤的动物模型,观察心肌细胞中超氧化物岐化酶(SOD)的水平,推断细胞内活性氧的生成量;观察培养液中乳酸脱氢酶(LDH)活性改变以判断细胞损伤情况;并进行DNA琼脂糖凝胶电泳及末端脱氧核苷酸介导的脱氧尿苷三磷酸缺口末端标记法(TUNEL),以判断细胞死亡类型及程度。结果血府逐瘀汤可显著升高缺血再灌注时SOD的水平,显著降低LDH的水平。DNA电泳图谱表明:血府逐瘀汤可使DNA的拖尾基本消失;TUNEL显示血府逐瘀汤可显著减少缺血再灌注所致的心肌细胞死亡。结论血府逐瘀汤有保护缺血再灌注时心肌细胞免于死亡之功效。  相似文献   
76.
Data on body composition in conjunction with reference centiles are helpful in identifying the severity of growth and nutritional disorders in infancy and for evaluating the adequacy of treatment given during this important period of rapid growth. Total body fat (TBF) and fat-free mass (FFM) were estimated from total body electrical conductivity (TBEC) measurements in 423 healthy term Caucasian infants, aged 14-379 days. Cross sectional age, weight, and length related centile standards are presented for TBF and FFM. Centiles were calculated using Altman's method, based on polynomial regression and modelling of the residual variation. The TBF percentage steeply increased during the first half year of life, and slowly declined beyond this age. Various simple TBEC derived anthropometric prediction equations for TBF and FFM are available to be used in conjunction with these standards. Regression equations for the P50 and the residual SD, depending on age, weight, or length, are provided for constructing centile charts and calculating standard deviation scores.  相似文献   
77.
1. Major risk factors for coronary heart disease (CHD) are smoking, blood pressure and blood cholesterol and they interact in a multiplicative fashion. Family history of premature coronary heart disease and lack of exercise also contribute. Obesity increases risk probably mainly by its effect on blood cholesterol and blood pressure. Heavy alcohol consumption is a risk factor for stroke. 2. Prevention may be opportunistic or in specially organized clinics, the latter being less likely to result in the attendance of high risk individuals. 3. Worthwhile reductions in cigarette smoking can be achieved by brief advice and follow-up. Literature on smoking and other aspects of prevention is available from the district health education department. 4. Risk scores can be used to calculate the risk of coronary heart disease. They can help to indicate the advisability of measurement of blood cholesterol and to focus limited resources on those at highest risk by helping to define a ''special care group''. 5. Indications for measuring blood cholesterol are: a family history of premature coronary heart disease or hyperlipidaemia, personal history of coronary heart disease, clinical evidence of raised lipids (xanthelasma, corneal arcus under 50, xanthomas at any age), a high risk of coronary heart disease according to a risk score. Many would also include those under treatment for hypertension and diabetes. 6. Dietary advice can moderately reduce blood cholesterol. The proportion of calories from fat should be reduced from the current average of around 40% to a maximum of 33%. Dietary advice should be tailored to the patient''s current diet. An increase in vegetables and fruit can be generally advocated. 7. Regular exercise has a worthwhile role to play in prevention. Rapid walking, jogging and swimming may all be suitable, as may be heavy gardening and housework. 8. A small proportion of patients may require lipid-lowering drugs. These include resins (cholestyramine and colestipol), fibrates (eg bezafibrate and gemfibrozil) and more recently HMG CoA inhibitors (eg simvastatin). The HMG CoA inhibitors produce large falls in cholesterol and may become first line drugs in future. Because of the current controversy about the effect of lipid-lowering drugs on total mortality, many believe that they should be reserved for those at the highest risk, for example patients with familial hypercholesterolaemia or with pre-existing coronary heart disease and a high plasma cholesterol (> 7.8 mmol/L). 9. The special care group defined by the practice should be offered regular follow-up.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
78.
79.
Roxatidine acetate, a new H2 receptor antagonist, was compared with ranitidine in the treatment of duodenal ulcers in a double-blind multicentre study. Eighty-four patients with endoscopically proven duodenal ulcer were randomized to receive 150 mg roxatidine acetate or 300 mg ranitidine at bedtime. Repeat endoscopy was performed after 4 weeks (25–33 days) and if the ulcer had not healed, another endoscopy was performed after a further 4 weeks of treatment. Using per protocol analysis 73.6% of ulcers treated with roxatidine healed at 4 weeks compared to 72.2% of ulcers treated with ranitidine (P=NS). The healing rates at 8 weeks were 92% with roxatidine and 83.3% with ranitidine (P=NS). Using equivalence tests, the healing rate of roxatidine was found to be equivalent to that of ranitidine within a 20% region. Roxatidine users took significantly less antacids than ranitidine users (P < 0.05). There were no significant adverse effects due to roxatidine or ranitidine. Roxatidine is a safe effective drug in the treatment of duodenal ulcers with a healing rate comparable to that of ranitidine.  相似文献   
80.
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