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Liver disease alters the pharmacokinetic and pharmacodynamic properties of hepatically eliminated drugs. The main factors influenced are plasma albumin levels, enzyme balance (induction & inhibition) and drug binding to tissue proteins. The influence of lidocaine on serum, heart and liver propranolol levels in Wistar rats after liver injury induced by carbon tetrachloride CCl4 0.4 ml/kg x 2/wkl, was investigated. 40 male Wistar rats were divided into four groups (I, II, III, IV; n=10), Group I animals received only propranolol (labelled + cold substance) 40 mg/kg/12 h p.o., group II propranolol plus lidocaine in a single dose of 4mg/kg s.c., group III was treated with CCl4 for 6 weeks and received propranolol x2 at the same dosage as group I, while group VI was treated with CCl4 and the same drug dosage as group II. The simultaneous administration of H3-propranolol and lidocaine increased propranolol levels in the serum and tissues. The liver in damaged animals showed an increase of propranolol level under lidocaine co-administration, probably due to CCl4 induced liver enzyme activity, resulting in a rapid propranolol metabolism or to competition between both drug protein binding sites. The increased propranolol levels in the heart after lidocaine administration were probably due to attributed to its high affinity for heart tissue. Consequently, as regards the therapeutic approach for patients with liver disease receiving propranolol their propranolol dosage should be reduced when lidocaine is co-administered.  相似文献   
23.
Coronary magnetic resonance angiography (CMRA) is a technique in clinical evolution. Current clinical applications include assessment for coronary anomalies, aneurysms, bypass graft patency, and, in experienced centers, the exclusion of proximal and multivessel coronary artery disease (CAD). As local expertise increases and more extensive multicenter data become available, additional applications will be established. CMRA promises to supplement and in some cases obviate the need for X-ray contrast angiography, and to expand our understanding of the pathophysiology of CAD. Zusammenfassung Die Magnetresonanzangiographie der Koronargefäße (CMRA) ist eine sich ständig weiterentwickelnde Technik. Etablierte Anwendungen sind zurzeit die Beurteilung von koronaren Anomalien, Aneurysmen und der Durchgängigkeit von Bypasses. Auch der Ausschluss proximaler Koronarstenosen und einer koronaren Mehrgefäßerkrankung ist in einigen spezialisierten Zentren möglich. Mit zunehmender Erfahrung der jeweiligen Anwender und der Verfügbarkeit von Ergebnissen großer multizentrischer Studien können zukünftig weitere klinische Anwendungen etabliert werden. In der Zukunft könnte die CMRA ergänzende Informationen zur Indikationsstellung einer konventionellen Röntgenangiographie bringen und in einigen Fällen diese Untersuchung sogar ersetzen. Die CMRA wird unseren Einblick in die Pathophysiologie der koronaren Herzerkrankung sicher erweitern.  相似文献   
24.
BACKGROUND: Adrenocortical carcinoma (ACC) is a rare and highly malignant tumour with a poor prognosis. Patients present with signs of steroid hormone excess (e.g., Cushing's syndrome) or symptoms due to an abdominal mass. DIAGNOSIS: In case of an adrenal mass, hormonal workup before surgery is required for differential diagnosis, perioperative management, and for follow-up. The imaging of choice is CT or MRI with MRI being of additional use when invasion of big vessels is suspected. Apart from that, the use of 18-FDG-PET is becoming increasingly established. TREATMENT: Surgical resection is the therapeutic option of choice in stages 1 - 3. In stage 4, the adrenolytic compound mitotane is part of the first-line treatment, but often needs to be combined with cytotoxic chemotherapy. Most patients will eventually have a recurrence, so adjuvant treatment (mitotane/tumour bed radiation) has to be considered in high risk patients, even if randomized controlled trials on adjuvant treatment are still lacking. STRUCTURAL PROGRESS: Several national and European structures have recently been established in order to increase our knowledge of ACC, improve therapeutic options and diagnostic procedures, and promote research. GANIMED, as a Germany-wide network of experts on adrenal diseases, has been founded allowing for improved gathering of data and joint studies. ENSAT (European Network for the Study of Adrenal Tumours) has been brought to life, aiming at European standards for therapy, diagnosis and tumour banking. Since 2003, patients can be enrolled in the German ACC Registry. France and Italy have also developed a central registry to collect nationwide data from patients with ACC. For the first time, patients with metastatic/unresectable ACC can participate in a prospective controlled randomized trial comparing two different cytotoxic chemotherapy regimes (FIRM-ACT).  相似文献   
25.
The present study compared four different sites and conditions for the measurement of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) in 38 spontaneous breathing tracheotomised patients. Of the patients, 28 had chronic obstructive pulmonary disease (COPD). The four different conditions were: 1) through a cuff inflated cannula (condition A); 2) through the mouth with a deflated cannula (condition B); 3) through the mouth with a phonetic uncuffed cannula (condition C); and 4) through the mouth after stoma closure (condition D). Five trials in each condition were performed using a standardised method. The measurement of both MIP and MEP differed significantly depending on the condition of measurement. MIP taken in condition A was significantly higher when compared with conditions B, C and D. MEP in condition A was significantly higher when compared with condition B and D. In condition A the highest frequency of the best measurement of MIP and MEP was observed at the fourth and fifth effort, respectively. The same results were obtained after the selection of only COPD patients. In conclusion, respiratory muscle assessment differs significantly depending on measurement condition. Measurement through inflated cannula tracheotomy yields higher values of both maximal inspiratory and maximal expiratory pressure.  相似文献   
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背景/目的:从1978-2000年,有10对联体双胞胎成功接受了手术分离,结果14人存活。其中6对是因为他们的联体同胞死亡或濒临死亡而接受紧急分离手术。剩余的4对,每对至少一个同胞接受至少一次的急诊手术后,才接受联体分离手术。方法:对这一独特的队列进行包含6个项目的问卷调查。问题的设计是开放式的,为父母/家庭提供有关信息的最大机会。对每个家庭就相同的问题也进行了当面的问卷调查。医师询问了与身体健康和疾病相关的一些问题。而社会工作询问了与发育、教育、社会心理和家庭功能相关的问题。结果:前面提及的14人存活的双胞胎中,4人大学毕业,1人于1981年完成中学学业,剩余9人正在上学。14人在最初的手术后,还需要接受再次手术,尤其是需要矫正泌尿系统、畸形、神经外科和小儿外科的问题。结论:通过超声检查对联体双胎进行宫内诊断,可以使医师和胎儿父母在孕早期决定在终止妊娠时是进行双胎分离还是保全其中一个。这些病例报道通过描述14例手术存活的长期体格检查和心理学检查结果,为医师和父母在关键时刻做出决定提供了另外有助的依据。  相似文献   
28.
In cystic fibrosis (CF), perturbations of total daily energy expenditure (TDEE) may be a major determinant of altered nutrition and growth. Measurement of TDEE is problematic, though the flex-heart rate method (FHRM) provides a close estimation of TDEE, as compared to the cost-prohibitive, gold standard, the double-labeled water method, and permits estimates of the energy cost of daily activities (ECA) above resting energy expenditure (REE). We hypothesize that alterations in ECA affects TDEE in CF. PURPOSE: To measure components of TDEE in adolescents with CF and normal lung function compared with controls, and to determine whether ECA can be improved by diet and exercise. METHODS: Clinically stable CF subjects (aged 9-13, n=12) and age- and gender-matched controls (n=13) had repeated measurements of TDEE by FHRM, REE, and maximal cardiopulmonary exercise testing (CPET) during a 6-week exercise and diet program. RESULTS: While the mean REE was similar in both groups, ECA was significantly lower in CF adolescents as compared to controls (p=0.02). During CPET, maximal exercise in CF was characterized by hyperventilation, which was unrelated to ventilation-perfusion mismatching. There were no changes in REE after dietary intervention. CONCLUSION: ECA in CF adolescents with normal lung function is lower when compared to healthy controls. These findings support the hypothesis that clinically stable patients with CF have inefficient energy metabolism or alternatively conserve energy during activities of daily living.  相似文献   
29.
Summary: A female patient with isovaleric acidaemia had a successful outcome from pregnancy.  相似文献   
30.
Although studies have documented underuse of controller medications and overuse of short-acting inhaled ss(2)-agonist among children with persistent asthma in disadvantaged communities, the persistence of oral ss(2)-agonist use in pediatric practice has not been studied since inhaled short-acting ss(2)-agonists became widespread. We describe medications used to treat asthma among children 3 to 5 years of age at 10 Head Start and other subsidized preschool centers in East and Central Harlem, New York City. We interviewed 149 parents/guardians of children who were identified as having probable asthma based on physician's diagnosis, persistent symptoms, hospitalization, and medication use. We classified 86 of the 149 children (58%) as having current persistent asthma. Only 15 of them (17%) were reported to have used controller medications at least 5 days/week in the last 4 weeks-only 2 of whom used inhaled corticosteroids. By contrast, 53 children (62%) used oral ss(2)-agonist in the last 4 weeks, often (72%) in conjunction with nebulized or inhaled short-acting ss(2)-agonist. Use of oral ss(2)-agonist was associated with more severe symptoms. This study documents the continued widespread use of oral ss(2)-agonist for treatment of children in a low-income community with high prevalence of asthma.  相似文献   
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