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INTRODUCTION: Ischemic heart disease is a major cause of heart failure in western societies. However, the factors that may influence left ventricular function (LVF) recovery after an acute coronary syndrome (ACS) are still unclear. OBJECTIVE: To identify variables that may influence LVF evolution one year after ACS. METHODS: 104 patients hospitalized with ACS between 7/1/2001 and 12/31/2002 and with systolic dysfunction--defined as an echocardiographic ejection fraction (EF) < or = 45%--were randomly allocated to a planned coronary follow-up program (FUP) or a general cardiology clinic (GC); patients from both groups were also randomly referred to a structured cardiac rehabilitation program (CRP). EF was re-assessed at one year. We compared differences between patients who recovered left ventricular function (EF > 45%; group 1) and those who did not (group 2). RESULTS: One year after discharge, 44.2% of the patients had recovered function. There were no significant differences between the groups in gender (77.7 vs. 76.5% male), age (56 vs. 59 years), hypertension, diabetes, dyslipidemia, smoking habits or family history. A previous history of cardiovascular events was more frequent in group 2 (11.1% vs. 35.3%, p = 0.03). Cardiac catheterization was performed before discharge in 88.8% and 88.2% in groups 1 and 2 respectively (p = NS); no differences were found in coronary anatomy between the two groups. Angioplasty was performed in 54.2% in group 1 and 50% in group 2 (p = NS). There were no differences in the use of angiotensin-converting enzyme inhibitors (83.3% vs. 87.5%), beta-blockers (87.5% vs. 87.5%), nitrates (37.5% vs. 33.3%), aspirin (95.8% vs. 95.8%), statins (79.1% vs. 75%) or diuretics (20.8% vs. 45.8%). There was no significant difference in LVF recovery between patients randomized to FUP or GC (38.5% vs. 54.5%). 87.5% of patients who completed the CRP had normal EF at one year compared to 32.7% of patients not referred to the program (p = 0.009). Although EF improved in both groups, this improvement was greater in patients who completed a CRP (EF 8% vs. 5%, p = 0.003). CONCLUSION: A previous cardiovascular event and completion of a CRP were the only variables that influenced LVF recovery. Thus, enrollment in a CRP, in addition to standard therapy, could be an important therapeutic measure in patients with systolic dysfunction after ACS; our data suggest that these programs should be more widely used.  相似文献   
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One hundred and one participants received In Control: A Home Video Freedom from Smoking Program. Of 53 completing self-treatment, 31 were verified by CO testing as abstinent one month after completion. Twenty-one per cent of the sample (40 per cent of those completing treatment) had not smoked in the past three months prior to 12 month follow-up and 16 per cent of the total sample (30 per cent of those completing treatment) had not smoked at all in the past 11 months.  相似文献   
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61 adults, with fixed or removable dental protheses, completed a 6-month double-blind trial comparing the clinical and microbial effects of brushing twice daily with either 0.22% NaF or 0.4% SnF2. Those subjects brushing with SnF2 had less gingivitis and fewer bleeding sites for both "total teeth" and "abutment teeth". Plaque scores between groups were only statistically different for the "abutment teeth". The microbial parameters, salivary S. mutans and subgingival plaque total CFU, were significantly reduced in the SnF2 group. In both treatment groups, there was a reduction over the course of the study in the number of subjects with recoverable A. actinomycetemcomitans and black pigmented bacteroides, yet there was no difference between groups.  相似文献   
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BACKGROUND: Peanut allergy is a major health concern due to the increased prevalence, potential severity, and chronicity of the reaction. The cDNA encoding a third peanut allergen, Ara h 3, has been previously cloned and characterized. Mutational analysis of the Ara h 3 IgE-binding epitopes with synthetic peptides revealed that single amino acid changes at critical residues could diminish IgE binding. METHODS: Specific oligonucleotides were used in polymerase chain reactions to modify the cDNA encoding Ara h 3 at critical IgE binding sites. Four point mutations were introduced into the Ara h 3 cDNA at codons encoding critical amino acids in epitopes 1, 2, 3 and 4. Recombinant modified proteins were used in SDS-PAGE/Western IgE immunoblot, SDS-PAGE/Western IgE immunoblot inhibition and T cell proliferation assays to determine the effects of these changes on in vitro clinical indicators of peanut hypersensitivity. RESULTS: Higher amounts of modified Ara h 3 were required to compete with the wild-type allergen for peanut-specific serum IgE. Immunoblot analysis with individual serum IgE from Ara-h-3-allergic patients showed that IgE binding to the modified protein decreased approximately 35-85% in comparison to IgE binding to wild-type Ara h 3. Also, the modified Ara h 3 retained the ability to stimulate T cell activation in PBMCs donated by Ara-h-3-allergic patients. CONCLUSIONS: The engineered hypoallergenic Ara h 3 variant displays two characteristics essential for recombinant allergen immunotherapy; it has a reduced binding capacity for serum IgE from peanut-hypersensitive patients and it can stimulate T-cell proliferation and activation.  相似文献   
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We studied lung explants in submersion organ culture to examine the role of the developing fetal alveolar epithelium in the production of lung fluid. Fourteen-day-gestation fetal rat lungs were grown in a collagen gel matrix supplemented with F-12 media and 10% fetal calf serum. In this model, the lung continues to grow, secrete fluid, and become progressively cystic in morphology. There is gradual thinning of the distal epithelial layer, which is lined by alveolar type II cells and their precursors. After 6 to 8 days in culture, we impaled the cyst walls with a microelectrode and continuously recorded the transepithelial potential (psi t). Stable, baseline transepithelial potentials of -1.1 to -6.2 mV (mean +/- SEM = -3.3 +/- 0.11 mV, lumen negative, n = 34) were measured in bicarbonate-buffered Ringer's solution, suggesting active electrolyte transport. When bumetanide, an inhibitor of chloride secretion in other systems, was added to the bathing solution, psi t decreased from a baseline of -3.5 +/- 0.07 mV (mean +/- SEM) to a value of -2.2 +/- 0.07 mV, suggesting chloride transport contributes to the voltage (n = 18, P less than 0.0005). Isoproterenol hyperpolarized psi t from a baseline of -4.3 +/- 1.0 mV to -6.5 +/- 1.0 mV (n = 7, P less than 0.005). 8-(4-Chlorophenylthio) adenosine 3':5'cyclic monophosphate (CPT-cAMP) plus isobutylmethylxanthine (IBMX) similarly hyperpolarized psi t from a baseline of -4.6 +/- 0.4 mV to -7.3 +/- 0.7 mV (n = 11, P less than 0.005). Addition of bumetanide after stimulation with isoproterenol or CPT-cAMP/IBMX depolarized psi t.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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BACKGROUND: Peanut allergy is an important health problem in the United States, affecting approximately 0.6% of children. Inadvertent exposure to peanut is a risk factor for life-threatening food-induced anaphylaxis. OBJECTIVE: The purpose of this investigation was to develop an immunoassay for a major peanut allergen, Ara h 1, to detect peanut allergen in foods so that the risk of inadvertent exposure can be reduced. METHODS: A specific 2-site monoclonal antibody-based ELISA was developed to measure Ara h 1 in foods. The sensitivity of the assay was 30 ng/mL. Ara h 1 was measured in foods (n = 83) with or without peanut and in experiments to optimize allergen yield and to determine peanut contamination in spiked foods. RESULTS: Ara h 1 levels in food products ranged from less than 0.1 microg/g to 500 microg/g. Ara h 1 measured in ng/mL was transformed to microg/g for food products. Peanut butter contained the highest amounts of Ara h 1. Peanut extracts contained from 0.5 to 15 mg Ara h 1/g of peanut depending on the extraction conditions. Optimal extraction of Ara h 1 was obtained by using phosphate buffer with 1 mol/L NaCl and Tween at 60 degrees C. Ara h 1 was not always detected in presence of chocolate under the extraction conditions tested. Spiking experiments showed that the assay could detect approximately 0.1% Ara h 1 contamination of food with ground peanut. There was an excellent correlation between Ara h 1 levels and peanut content measured by using a commercial polyclonal antibody-based ELISA (r = 93, n = 31, P <.001). CONCLUSION: A new sensitive and specific monoclonal antibody-based ELISA was used to monitor Ara h 1 content in food products. This assay should be useful for monitoring peanut contamination in the food manufacturing and processing industry and in developing thresholds for sensitization or allergic reaction in persons with peanut allergy.  相似文献   
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Curative surgery for gastric cancer: Study of 166 consecutive patients   总被引:1,自引:0,他引:1  
From January 1980 to December 1991 we operated on 295 patients with a gastric carcinoma. In 166 cases (56.3%) surgery was performed with curative intent. In 93 patients (56%) a subtotal gastrectomy was performed, and in 73 cases (44%) a total gastrectomy. In all the cases a D-2 type lymphadenectomy was used. The global morbidity rate was 23%, and in-hospital mortality was 3.6%. The morbidity and mortality rates of these two operations were statistically different. Global 5-year survival estimate for the whole series is 61.3%. Univariate and multivariate analysis according to T and N (TNM classification), the number of positive nodes resected, and the relation of positive per resected nodes, revealed statistically different outcomes. This kind of quantitative classification allowed identification of high risk groups irrespective of site of nodal involvement. Tumors classified as intestinal or diffuse type by the Lauren classification had similar survival curves and 5-year survival estimates (p=0.834). By univariate and multivariate analysis this classification did not reveal a prognostic value in this group of patients. In our opinion, tumor penetration and lymph node involvement are at present the most reliable prognostic factors available.
Resumen En el período enero 1980 a diciembre 1991 se operaron 295 pacientes con carcinoma gástrico. En 166 (56.3%), la cirugía fue realizada con intención curativa; en 93 (56%) se realizó gastrectomía subtotal y en 73 (44%) gastrectomía total. En la totalidad de los casos se realizó linfadenectomía D-2. La mortalidad global fue 23% y la mortalidad hospitalaria 3.6%. Las tasas de mortalidad y morbilidad de estas dos operaciones aparecieron significativamente diferentes. La sobrevida global a cinco años estimada para la totalidad de la serie es de 61.3%. Los análisis uni y multivariables de acuerdo con la clasificación TNM, el número de ganglios positivos resecados y la relación positivos/resecados revelaron resultados estadísticamente diferentes. Este tipo de clasificación cuantitativa permitió la identificación de Grupos de alto riesgo independientes del lugar de la invasión ganglionar. Los tumores clasificados como intestinales o difusos (clasificación de Lauren), registraron similares curvas de sobrevida y de sobrevida estimada a cinco años (P=0.834). Mediante el análisis univariable y multivariable esta clasificación no demostró tener valor pronóstico en nuestro Grupo de pacientes. En nuestra opinión, el grado de penetración del tumor y la invasión ganglionar son los factores de pronóstico más confiables.

Résumé Entre Janvier 1980 et Décembre 1991, nous avons opéré 295 patients ayant un cancer gastrique. Chez 166 (56.3%), l'exérèse a été jugée curative. Chez 93 (56%) des cas, il s'agissait d'une gastrectomie subtotale alors que dans 73 (44%) cas, une gastrectomie totale a été pratiquée. Dans tous les cas une lymphadénectomie du type D-2 lui a été associée. La morbidité globale a été de 23% et la mortalité hospitalière de 3.6%. La morbidité et la mortalité des deux types d'intervention différaient de façon statistiquement significative. La survie à 5 ans de la série en entier a été de 61.3%. Une analyse uni et multifactorielle a pu mettre en évidence une différence statistiquement significative en ce qui concerne la survie par rapport à la classification T-N (TNM), le nombre de ganglions réséqués et le nombre de ganglions envahis/nombre de ganglions enlevés. Cette analyse a permis d'identifier les malades à haut risque, indépendamment du site de l'envahissement lymphatique. La courbe de survie et la survie estimée à 5 ans étaient identiques selon que la tumeur a été classée intestinale ou diffuse selon Lauren. Cette classification n'a pas, pourtant, de valeur pronostique d'après les analyses uni et multifactorielle. A notre avis, la pénétration tumorale et le degré d'envahissement lymphatique sont les deux facteurs pronostiques les plus constants.
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