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Background and ObjectiveSchool smoking prevention programs have never yielded the expected results. The aim of this study was to analyze the efficacy of an intensive smoking prevention program created by the educational community in which it was to be applied.Population and MethodA 3-year smoking prevention program was carried out among the students of Fuentesaúco Secondary School in Zamora, Spain. The Babilafuente Secondary School in Salamanca, Spain was the control group. The program included both prevention and treatment activities. The former were carried out in the school, in out-of-school situations, and in the community. The questionnaire of the European Smoking Prevention Framework Approach was used.ResultsA total of 417 students aged 12 to 17 years participated in the study. Of these, 54.4% belonged to the intervention group and 45.6% to the control group. Smokers represented 36.7% of the population. After the intervention smokers represented 40.1% of the Fuentesaúco students compared with 46.1% of the Babilafuente students, though the difference was not statistically significant. With respect to the cognitive determinants of smoking behavior, after the intervention significant differences in favor of the intervention group were only observed in the subjects’ perception of the behavior of their siblings, peers, and teachers.ConclusionsThe use of smoking prevention programs in schools should be reconsidered, and their evaluation should be based on educational rather than clinical criteria. Proposed changes in the program include decreasing its intensity, starting with students of an earlier age and seeking greater involvement of parents.  相似文献   
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Forty consecutive adult patients under the age of 50 with acute non-lymphoblastic leukemia (ANLL) in first complete remission, underwent autologous bone marrow transplantation (ABMT) between March 1984 and April 1990. The conditioning regimen employed included cyclophosphamide and total body irradiation, followed by the administration of unpurged ABMT. The median time from diagnosis to transplant was 7 months (3-15 months), and the median time from complete remission to ABMT was 4 months (range 3-9 months). Twenty-two (51%) patients remain in complete remission 6-81 months (median 24 months) after ABMT.

The causes of death were, recurrent leukemia (11 patients), parenchymal toxicities such as acute respiratory distress syndrome and veno-occlusive disease (3 patients), hemorrhage (2 patients) and infection (2 patients). Eleven patients relapsed after 3-12 months (median 5 months). This study has produced survival data comparable to those of other institutions employing TBI for either allo or autotransplants.  相似文献   
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BACKGROUND: It has been reported that patients on a very-low-protein diet (VLPD) maintain a satisfactory nutritional status because of a conserved adaptive metabolic response. However, only few studies have examined the course of nutritional status and body composition in the long term (2 years). METHODS: Thirteen stable patients (8 men; age, 55 +/- 12 years; glomerular filtration rate (GFR), 15 +/- 5 mL/min) receiving a VLPD (0.3 g/kg/day protein) supplemented with amino acids and ketoanalogues (SVLPD) were studied for 2 years. A joint visit with a physician and a dietitian and routine blood and urine analyses were performed every month. Dual-energy x-ray absorptiometry (DEXA), which was used to assess modification of body composition, and GFR (urinary 51Cr-EDTA) and urinary urea and creatinine excretion, which were used to assess nutritional status and compliance to the diet, were assessed every 3 months. RESULTS: GFR, albumin, and prealbumin levels remained stable. Urea urinary excretion decreased at 3 months and then slightly increased at 2 years, but the calculated protein intake remained low at 0.38 +/- 0.1 g/kg/day. Energy intake remained close to 30 kcal/kg/day. No significant change was observed for total fat mass or percent fat mass. After an initial decrease, lean body mass stabilized at 6 months and then increased significantly from 6 to 24 months (P =.02, paired t-test); the mean increase during this period was of 2 kg, that is, 4.6%. Urinary creatinine excretion showed the same profile. Total bone mass, lumbar or hip site bone mass, and Z-score significantly decreased from T0 to 1 and 2 years (P <.05). CONCLUSION: This study confirms that a supplemented VLPD is nutritionally safe for a long period, but attention must be paid to bone mass.  相似文献   
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It was shown previously that chronic exposure to opiate agonists increases adenylyl cyclase (AC) activity, a phenomenon termed AC superactivation (or supersensitization). More recently, we showed that acute Gi/o-coupled receptor activation inhibits the activity of several AC isozymes, including Ca2+/calmodulin-stimulated AC-I and -VIII, whereas chronic receptor activation induces their superactivation. Here, we report that both acute μ-opioid receptor-induced inhibition and chronic induced superactivation of AC-I and -VIII are pertussis toxin sensitive. In addition, we show that proteins that interfere with the activity of {ie195-2} subunits ({ie195-3} scavengers) strongly attenuate the acute inhibition of AC-I and -VIII and the superactivation of AC-I, and abolish the superactivation of AC-VIII. Based on these results, we suggest that {ie195-4} is involved in the acute inhibition and chronic agonist-induced superactivation of AC types I and VIII.  相似文献   
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A high-performance liquid chromatographic (HPLC) method is described for the assay of the active metabolite [1-(2-pyrimidinyl)piperazinel of buspirone, an anxiolytic agent, in rat plasma.

The method is based on the use of ion-pair HPLC coupled to a liquid—solid extraction scheme. Samples of rat plasma (2 ml) with internal standard (1-phenylpiperazine), adjusted to pH 10.5 with borate buffer, were loaded on to a preactivated C-18 cartridge. The metabolite and the internal standard were eluted with 5 ml of methanol and injected on to a reversed-phase 10-μm Spherisorb ODS-2 column. The column was eluted with a mobile phase of 0.005 M sodium lauryl sulphate in citrate buffer (pH 3.6)-acetonitrile (65:35, v/v) at 2 ml min−1. Detection was carried out at 248 nm. The recovery of the metabolite was 55%. The method was applied to the determination of the metabolite in rat plasma after oral dosing (25 mg kg−1) of the parent compound.  相似文献   

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