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21.
Polymorphisms of genes coding for DNA repair can affect lung cancer risk. A common single nucleotide (-4) G-to-A polymorphism was identified previously in the 5' untranslated region of the XPA gene. In a case-control study in European Caucasians, the influence of this polymorphism on primary lung cancer risk overall and according to histologic subtypes was investigated. Four hundred sixty-three lung cancer cases (including 204 adenocarcinoma and 212 squamous cell carcinoma) and 460 tumor-free hospital controls were investigated using PCR amplification and melting point analysis of sequence-specific hybridization probes. Odds ratios (OR) were calculated by multiple logistic regression analysis adjusting for age, gender, smoking habits, and occupational exposure and showed a slightly enhanced risk for all lung cancer cases as well as for squamous cell carcinoma and adenocarcinoma cases. Gene-environment interactions were analyzed with respect to smoking and occupational exposure. A nearly 3-fold increased risk for adenocarcinoma associated with the XPA AA genotype was observed for occupationally exposed individuals (OR, 2.95; 95% confidence interval, 1.42-6.14) and for heavy smokers (OR, 2.52; 95% confidence interval, 1.17-5.42). No genotype-dependent increase in OR was found for nonexposed individuals or those smoking <20 pack-years. The significant effect of the XPA polymorphism in heavy smokers and occupationally exposed individuals suggests an important gene-environment interaction for the XPA gene. The underlying mechanisms as to why AA homozygotes are predisposed to lung adenocarcinoma and which specific carcinogens are involved remains to be determined.  相似文献   
22.
Fifty fetuses referred to the Polish Mother's Memorial Hospital for fetal echocardiography between January 1, 1991 and June 1, 1995 were evaluated. The mean fetal gestational age at the time of diagnosis of arrhythmia was 34.1 weeks, and the mean gestational age at the time of delivery was 38.7 weeks. Checkup echocardiographic examinations were performed every 10–14 days, for a mean 2.4 studies per fetus. In most cases (48/50, 96%), premature atrial contractions were present during the first echocardiography examination. The fetal heart study was normal in 30 cases; in 7 (14%) there was tricuspid valve regurgitation, in 7 (14%) an atrial septal aneurysm, in 4 congenital heart defects, in 1 myocardial hypertrophy, and in 1 disproportion in the four-chamber view. Of the 50 fetuses, 43 underwent regular echocardiographic monitoring alone; in 7 cases, based on the presence of additional echocardiographic findings, pharmacotherapy was applied (digoxin, verapamil, or both). Three neonates died after delivery owing to malformations in two cases (one critical aortic stenosis, one spina bifida plus hygroma colli) and due to myocarditis in one case. In six of seven newborns treated in utero, myocarditis was diagnosed after birth (including the one with neonatal demise). Most of the newborns were in good condition after birth, their mean Apgar score being 8.6 and the mean birth weight 3259 g. We concluded that most extrasystoles represent an isolated anomaly, not affecting the fetal condition. Their presence should not influence the obstetric care and may require only echocardiographic monitoring. In most of our cases the premature contractions subsided after birth, although sometimes they preceded fetal supraventricular tachycardia or appeared after congenital myocarditis.  相似文献   
23.
A placebo controlled, double-blind trial of mecamylamine treatment of cocaine dependence was performed in methadone or LAAM maintained subjects who met DSM-IV criteria for cocaine dependence. After an eight-week placebo run-in screening period, 35 subjects were randomly assigned to receive either mecamylamine (6 mg/day) or placebo transdermal patches for a 16-week treatment period. Outcome measures included quantitative urine benzoylecognine (BE) levels, self-report of cocaine use, cocaine craving, global impression scores, mood, retention, and safety. Mecamylamine was well tolerated, and study retention did not differ by treatment group. Evidence for cocaine use, based on urine BE levels and cocaine abstinence rates, did not differ by treatment group. Self reported cocaine use, cocaine craving, and global impression scores showed moderate improvement in both groups, with a significantly greater reduction in cocaine craving (p < 0.05) and self-rated severity of cocaine dependence (p < 0.05) in the placebo group. This pilot study does not support the effectiveness of mecamylamine for the treatment of cocaine dependence in methadone or LAAM maintained patients.  相似文献   
24.
Gathering and eating mushrooms and other plants containing psychoactive substances has become increasingly popular among young people experimenting with drugs. Dried fly agaric Amanita muscaria fruiting bodies were eaten by five young persons (18-21 years of age) at a party in order to evoke hallucinations. Visual and auditory hallucinations occurred in four of them, whereas a 18-year-old girl lost consciousness. The following morning, she went to the Clinic of Toxicology. Due to the fact that not all the active substances present in the fly agaric have been identified, and some of them have an effect after a period of latency, the patient was admitted for several days of observation during which check-up examinations were performed. After four days without any problems, she was discharged. The poisoning regressed with no organ complications. The remaining persons who had eaten the fly agaric were free from any complaints.  相似文献   
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Body composition and body mass are pivotal clinical endpoints in studies of welfare diseases. We present a combined effort of established and new mathematical models based on rigorous monitoring of energy intake (EI) and body mass in mice. Specifically, we parameterize a mechanistic turnover model based on the law of energy conservation coupled to a drug mechanism model. Key model variables are fat-free mass (FFM) and fat mass (FM), governed by EI and energy expenditure (EE). An empirical Forbes curve relating FFM to FM was derived experimentally for female C57BL/6 mice. The Forbes curve differs from a previously reported curve for male C57BL/6 mice, and we thoroughly analyse how the choice of Forbes curve impacts model predictions. The drug mechanism function acts on EI or EE, or both. Drug mechanism parameters (two to three parameters) and system parameters (up to six free parameters) could be estimated with good precision (coefficients of variation typically <20 % and not greater than 40 % in our analyses). Model simulations were done to predict the EE and FM change at different drug provocations in mice. In addition, we simulated body mass and FM changes at different drug provocations using a similar model for man. Surprisingly, model simulations indicate that an increase in EI (e.g. 10 %) was more efficient than an equal lowering of EI. Also, the relative change in body mass and FM is greater in man than in mouse at the same relative change in either EI or EE. We acknowledge that this assumes the same drug mechanism impact across the two species. A set of recommendations regarding the Forbes curve, vehicle control groups, dual action on EI and loss, and translational aspects are discussed. This quantitative approach significantly improves data interpretation, disease system understanding, safety assessment and translation across species.  相似文献   
27.
Type 1 diabetes (T1DM) is an autoimmune disease that requires insulin treatment from the time of diagnosis. Its clinical course depends on both genetic and environmental factors, and the lifestyle of a patient modulates their interaction. The evidence about the influence of lifestyle on the course of T1DM is increasing. In this paper, we present evidence on the relationship between lifestyle parameters and diabetes-related outcomes. We discuss the most commonly addressed factors associated with lifestyle, such as physical activity, nutrition and smoking, and those with sparse evidence in T1DM, such as socioeconomic status, sleep duration, psychological stress and illicit drugs intake.  相似文献   
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Phenylketonuria (PKU) is an autosomal recessive metabolic disease caused by an error of phenylalanine metabolism. Delayed treatment or treatment performed unsystematically might lead to neurological disorders and progressive intellectual disability. In the Prader-Willi syndrome (PWS) clinical manifestations change with age. Feeding difficulties resulting from the poor suck and hypotonia are typical in the neonatal period and early infancy. As patients grow their activities increase, muscle tone improves, the extreme hyperphagia appears – the main cause of obesity. Mental development of patients is usually mildly retarded. We report the case of a patient affected by two genetic diseases: PKU and PWS. Variety of clinical symptoms and abnormal results of laboratory analyses make the correct diagnosis difficult. Elevated phenylalanine level in screening newborn test, disorders of muscle tone, poor suck, and low urine biopterin concentration did not allow to clearly rule out the hyperphenylalaninemia caused by a tetrahydrobiopterin deficiency (BH4). Data from obstetric anamnesis and the early postnatal clinical findings suggested the PWS. Hyperphagia and the increased risk of carbohydrates tolerance disorders in patients with PWS make it very difficult to balance properly the low-phenylanine diet necessary in PKU treatment. The patient presented by us needs well-coordinated multidisciplinary medical care which aims to provide proper physical development and to support the boy's mental potential as well as appropriate functioning in the society.  相似文献   
30.
Bronchial asthma is the most common chronic disease in children of developmental age. Data from the auxological literature indicate that children with disturbances in growth may also suffer from atopic disorders. The aim of the present study was to evaluate somatic growth in children with bronchial asthma using anthropological methods. The study was carried out using anthropometric measurements and information on the severity and course of the disease on 261 children with bronchial asthma. Mean body height was lower than in healthy peers and about 5% of subjects were short. Mean BMI and skinfold thicknesses were significantly higher and lean body mass was lower in the study group. Seventeen percent of the children were overweight or obese, and 8% were underweight. Body build was more robust in the girls examined. Longitudinal studies will help determine to what degree the disease itself directly affects physical development, and to what degree treatment does.  相似文献   
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