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991.
992.
The bronchomotor effects of a deep inhalation (DI) may provide relevant information about the mechanisms of exercise-induced airway obstruction in children and may be assessed by respiratory conductance (Grs) measured using the forced oscillation technique. The aims of the present study were to assess the effect of DI on Grs after exercise in relationship to the lung function response to exercise. Grs at 12 Hz using a head generator and spirometric data were measured in 62 children suspected of asthma before and 5 min after a 6-min free run. After exercise, Grs was significantly increased by DI in 38 subjects, who also showed larger Grs and forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) responses to exercise than the 24 nonresponders. Stepwise regression indicated significant correlation between the response of Grs to DI and both Grs and FEV1/FVC responses to exercise. The data are consistent with exercise-induced bronchoconstriction being reversed by deep inhalation.  相似文献   
993.
Conflicting results are to be found in the literature on the relationship between the M235T polymorphism of the angiotensinogen (AGT) gene and hypertension. The controversy may be due to insufficient numbers of subjects, the variability of the inclusion criteria and the different genotype analysis methods used. We have experienced that the most frequently used, original polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method involves significant uncertainties when the TT genotype is determined, independently of the restriction digestion. To make the determination more accurate, we improved the PCR by designing a new antisense primer containing only one mismatch instead of the two in the original protocol and also by adding DMSO to the PCR reaction mixture. The original and our improved methods were compared by using DNA from 123 patients: parallel determinations resulted in values of 33 MM, 90 MT and 0 TT with the original method and of 33 MM, 56 MT and 34 TT with the improved RFLP protocol. In summary, a plausible explanation for some of the conflicting data published on AGT M235T polymorphism may be that inaccuracies arose during the determination of the genotype.  相似文献   
994.
BACKGROUND: Identify risk factors for asthma in adolescents from S?o Paulo, Brazil. METHODS: total of 528 adolescents (141 asthmatics, 387 control subjects) from the ISAAC study (phase III) were submitted to a complementary questionnaire to evaluate risk factors, through response to questions regarding personal history, environment, and diet and an agreement to undergo the skin prick test (SPT) for aeroallergens. RESULTS: Positive SPT to at least one allergen occurred in 49.4% adolescents. The risk factors for asthma were: prematurity (OR: 3.84, 95% CI: 1.54-9.64), rhinitis (OR: 3.18, 95% CI: 1.71-5.91), positivity in the SPT (OR: 2.81, 95% CI: 1.48-5.32), eczema in characteristic skin-folds (OR: 2.86, 95% CI: 1.13-7.26), and an allergic mother (OR: 2.01, 95% CI: 1.02-3.93). The consumption of cooked vegetables was a protective factor for asthma (OR: 0.37, 95% CI: 0.18-0.79) CONCLUSIONS: Asthma is a multifatorial disease. An allergic mother, aeroallergen sensitization, rhinitis, eczema and prematurity were considered risk factors and the consumption of cooked vegetables was considered a protective factor for asthma in this population.  相似文献   
995.
OBJECTIVES: This article examines the differences found between clientele with severe mental health problems and their key health workers in terms of assessing service users' needs in 6 Quebec service areas. METHOD: We questioned 165 pairs of users and staff, using the Camberwell Assessment of Needs questionnaire. The profile of serious and overall problems encountered by clientele from each of the sites was compared. RESULTS: The sites with the greatest degree of user-staff agreement in identifying problems were also the ones where users considered that local services best met their needs. CONCLUSIONS: The study demonstrated that, in needs assessment, major differences exist between the perceptions of users and their key workers in the various sites. These differences can be explained in part by users' individual characteristics, by types of needs, by local particularities, and by service use.  相似文献   
996.
997.

Background  

While the mortality of esophageal surgery has decreased due to technological advancements, there is still a complication rate of about 30%. One of the main complications is the anastomotic leakage associated with a significant rate of morbidity and mortality. To close the leakage the efficacy of self-expanding stents (SES) has been shown in different studies. However, the high rate of stent migration limits the use of commercial available stents. In our case we were faced with the problem that the diameter of all available stents was too small to attach tightly to the mucosal wall of the esophagogastric anastomosis.  相似文献   
998.
Objective To describe dislocation of the elbow with articular fracture of the distal humerus,a type of elbow fracture-dislocation about which little has been written.Methods Four patients with a dislocation of the elbow and fracture of the distal humerus were identified.Three had dislocation and complex intraarticular fracture of the capitellum,trochlea,and lateral epicondyle.Results Two patients(one treated with a second operation to address avascular necrosis of the capitellum)achieved a functional arc of elbow motion and one patient was lost after removal of the implants 3 months after fracture with documented healing.The fourth patient had a complex open fracture dislocation involving the entire articular surface.An attempt to salvage the articular surface resulted in deep infection.Extensive heterotopic bone led to arthrodesis of the elbow.Conclusions Dislocations of the elbow with articular fracture of the humerus are uncommon.Most injuries involve the capitellum,lateral trochlea,and lateral epicondyle.Open reduction and internal fixation of the distal humerus fracture can restore stability without repairing the medial collateral ligament.  相似文献   
999.
Susceptibility to invasive amebiasis has been suggested to be due to intrinsic amebic factors and/or to such host factors as intestinal microflora, mucus and colonic redox potential. We investigated the effect of rat colon components on the growth of axenically cultured E. histolytica trophozoites. Extracts of rat colon tissue produced a 57% amebic growth inhibition. The main growth inhibitory components were precipitated by 65% ammonium sulfate and were heat-sensitive. These components were partially separated by ultrafiltration and gel filtration chromatography. Thus, we found colonic components (Mr 50-100 kDa) that produced strong growth inhibition (75%). These results suggest that rat colonic products may play an active role in resistance to amebic infection.  相似文献   
1000.
To evaluate whether treatment with a mitogenic agent may increase bone formation and bone mass in osteopenia induced by estrogen deficiency, we determined the effect of oral fluoride treatment on bone and bone cells in ovariectomized rats. Sodium fluoride (NaF) was administered to 3-month-old ovariectomized rats 1 day after ovariectomy (OVX) for 1, 3, and 6 months. NaF was given in drinking water at the dose of 1 mg/kg body weight per day. Fluoride administration led to a partial prevention of the bone loss induced by OVX as shown by histologic analysis of tibial metaphysis and by evaluation of femoral calcium content. These beneficial effects of fluoride were more striking at early time points (1 and 3 months postovariectomy) than after 6 months of treatment. The increase in trabecular bone volume in OVX rats treated with fluoride was associated with a rise in the osteoblast surface, which was increased by 60, 72, and 235% at 1, 3, and 6 months postovariectomy compared to untreated OVX rats. In OVX rats and in sham-operated rats plasma osteocalcin was increased in correlation with the osteoblast surface. However, these two parameters were not correlated in OVX rats treated with fluoride. The heat-labile bone-specific alkaline phosphatase in plasma was decreased in OVX rats treated with fluoride compared to OVX rats, suggesting that both the number and the activity of osteoblasts were affected by NaF treatment. To examine the effect of fluoride on the osteocalcin production and the proliferative capacity of bone cells, osteoblastic cells were isolated by collagenase digestion from the bone surface of tibia in treated and untreated OVX rats.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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