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1.
SAPALDIA--the Swiss Study on Air Pollution and Lung Diseases in Adults--focuses on the long term health effects of low to moderate levels of air pollutants as typically seen in different parts of Switzerland. The aim of the SAPALDIA cross-sectional study carried out in 1991 was to determine the prevalence of bronchial asthma, chronic bronchitis and allergic conditions in the adult population of Switzerland and to identify and to determine the respective importance of potentially influencing factors. These could be both personal (smoking habits, allergy status, family history, occupation) and environmental (outdoor and indoor pollution, aeroallergens, climate). A further aim of the cross-sectional study consisted in the identification of individuals susceptible to present symptoms during a two year observation period and to be included in the SAPALDIA follow-up study. This technical report represents the methodological documentation for the cross-sectional study of SAPALDIA. The instruments and the methods of standardisation are presented and discussed. The medical examination consisted of a computerised interview using a standardised questionnaire, the taking of a blood sample for serological tests, allergy skin testing, the measurement of end expiratory CO and body height, and pulmonary function testing followed by methacholine challenge testing or bronchodilatation testing. The pattern of participation and the 9651 participants of the study, representing 59.3% of the sample, are described. Based on information on non-participants gained by telephone interviews and mailed short questionnaires, possible selection biases are quantified and discussed.  相似文献   

2.
Ample experimental evidence indicates that acute beta-amyloid infusion into the nucleus basalis of rats elicits abrupt degeneration of the magnocellular cholinergic neurons projecting to the cerebral cortex. In fact, involvement of a permanent Ca2+ overload, partially via N-methyl-D-aspartate (NMDA) receptors, was proposed as a pivotal mechanism in beta-amyloid-induced neurodegeneration. A definite measure of NMDA receptor-mediated processes and subsequent Ca2+ entry is the induction of Ca2+/calmodulin-activated neuronal nitric oxide synthase (nNOS) in nerve cells. In the present account we therefore assessed activation of nNOS in correlation with cholinergic decline after beta-amyloid(1-42) or beta-amyloid(25-35) infusion into the rat nucleus basalis. The results demonstrate the beta-amyloid conformation-dependent enhancement of cortical nitric oxide synthase (NOS) activity. Furthermore, chronic application of the polyamine site NMDA receptor blocker ifenprodil effectively attenuated beta-amyloid neurotoxicity. We propose that nNOS activation reflects the degree of beta-amyloid-induced excitotoxic injury in a proportional manner. Moreover, Ca2+-mediated processes via NMDA receptors, or direct binding of beta-amyloid to this receptor may be a critical step in the neurotoxic mechanisms in vivo.  相似文献   

3.
Upward spiralling health care expenditures have triggered the need to assess the cost-effectiveness of medical interventions. Specifically, interventions in primary and secondary prevention represent an important field of research. A resource utilization analysis was performed on the basis of the recently published Scandinavian Simvastatin Survival Study. It could be shown that treatment with simvastatin compared to placebo leads to a reduction in patient costs of CHF 8.4 million. This represents a reduction of CHF 3770.- per patient. The effective daily treatment costs can thus be calculated at CHF 1.11, which is equivalent to 36% of the actual acquisition cost per day. These results support the notion that secondary coronary prevention is not only justified from a clinical but also from an economic point of view.  相似文献   

4.
Electron paramagnetic resonance (EPR) and differential scanning calorimetry (DSC) have been used to study the effect on the phase transition of dimyristoylphosphatidylcholine membranes of incorporating various stearic acid spin labels (SASL's) that contain the bulky oxazolidine ring at various positions along the stearyl chain. SASL's lowered the phase transition temperature and decreased the size of the cooperative unit, with the effects stronger in the order of 9- > 12- > 5- > 16-SASL > stearic acid (no label). Incorporation of stearic acid without the spin label slightly increases the phase transition temperature. Incorporation of 9-SASL (3 mol% of lipid) decreased the transition temperature by 1.8 degrees C and the cooperative unit to 1/5 of that without the spin label, while the effect of 16-SASL was slight. The effect on transition enthalpy was small. It is concluded that the perturbing effect of placing a bulky group on the alkyl chain on phase transition is through inducing packing defects in the gel-phase.  相似文献   

5.
OBJECTIVES: To explain the preoperative assessment of the hypospadias cripple and define the fundamental principles of correction of the failed hypospadias repair. METHODS: Through case presentation and literature review, the defects associated with the failed hypospadias repair including persistent chordee, urethral stricture, urethrocutaneous fistula, urethral diverticulum, meatal retraction and stenosis, failed glansplasty are elaborated. Decision-making points in selecting a method of repair are also provided. RESULTS: The principles of successful reoperative hypospadias surgery are discussed and listed. CONCLUSIONS: A thorough assessment of the defect and precise application of standard principles of hypospadias repair allows for successful correction of even complex hypospadias cripples.  相似文献   

6.
BACKGROUND: Anemia of prematurity is characterized by low reticulocyte counts and inadequate erythropoietin response, for which many very-low-birth-weight infants receive multiple blood transfusions. We investigated whether early treatment of such infants with recombinant human erythropoietin would reduce their need for transfusions. METHODS: We performed a controlled, blinded trial in 241 infants with very low birth weights at 12 centers in six European countries. When three days old, the infants were randomly assigned either to the epoetin group or to the control group. Those in the epoetin group received 250 IU of epoetin beta per kilogram of body weight subcutaneously three times a week from day 3 to day 42 (for a total of 17 doses); those in the control group did not receive this drug. Infants in both groups received oral iron (2 mg per day) from day 14 onward. RESULTS: The control infants needed a mean of 1.25 transfusions each, as compared with 0.87 transfusion for epoetin-treated infants (P = 0.013). The median cumulative volume of blood transfused per kilogram per day was 0.41 ml in the control group (first quartile, 0 ml; third quartile, 0.8 ml) and 0.09 ml in the epoetin group (first quartile, 0 ml; third quartile, 0.8 ml) (P = 0.044). The rate of success, defined as an absence of need for transfusions and a hematocrit that never fell below 32 percent, was 4.1 percent in the control group and 27.5 percent in the epoetin group (P = 0.008). Epoetin was most beneficial in boys with birth weights of 1200 g or more and a base-line hematocrit of 48 percent or more. No toxic effects were observed in the epoetin group; as compared with the control group, the epoetin group had an increased incidence of septicemia (14 vs. 7 episodes, P not significant) and reduced weight gain (520 vs. 571 g, P = 0.02). CONCLUSIONS: Infants with very low birth weights have less need of transfusions if given epoetin beta during the first six weeks of life (250 IU per kilogram three times a week). We recommend early epoetin treatment for all such infants, but further studies of nutrition and iron supplementation during treatment are needed.  相似文献   

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