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971.
In our environment, some children with allergic respiratory pathology do not have as favorable an evolution as expected after three years of immunotherapy with D. pteronyssinus extracts. We believe this is due to the existence of other mites whose antigenic determinants are not present in D. pteronyssinus. The purpose of the present study was to evaluate skin cross-reactivity between Dermatophagoides and storage mites in children with bronchial asthma. Fifty patients were chosen, with a mean age of 7.78 +/- 2.98 years and a range of 3-14 years. There were 38 boys (76%) and 12 girls (24%) with rhinitis and bronchial asthma. All patients had skin tests and prick tests with the following extracts performed on them: house dust (HD), Dermatophagoides farinae (DFA), Dermatophagoides pteronyssinus (DPT), Acarus siro (AS), Glycyphagus domesticus (GD), Lepidoglyphus destructor (LD), Tyrophagus putrescentiae (TP), with negative and positive controls. The areas of the papulae were evaluated in crosses, according to the size of the histamine and using computerized papulometry, using the Kurta series one graphic tablet with one resolution of 200 points per inch. The data were processed with the "Image-pro" analysis image program. The following conclusions were obtained from our study: 1) No case of skin sensitization to storage mites was found in any of our 50 patients, without house dust and/or Dermatophagoides mites also being present. 2) The greatest skin response with regard to histamine was found for DFA (52%), DPT (44%), HD (22%), GD (10%), AS (4%) and GF (2%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
972.
A survey was conducted to determine the prevalence and distribution of filarial infections among the inhabitants of Comisaría. Approximately 25% of the 604 individuals bled (Knott's sample) harbored microfilariae; more men (29.7%) were infected than women (23.7%); approximately 6% were infected with Mansonella (=Dipetalonema) perstans, 13% with Mansonella ozzardi, and 7% with both filariae. Mansonella ozzardi was more common in men than in women, and its prevalence increased with age in both sex groups; it was detected in most of the resident ethnic groups but was most common in the Puinave and the Curripaco Indians, and appeared to be distributed throughout the Comisaría. The prevalence of M. perstans was essentially the same in men as in women, and in age-groups from the 2nd to 4th decade, although its tendency to increase with age was not as marked as in M. ozzardi infections. Mansonella perstans appeared to be limited to the central and southern regions of the Comisaría, was found principally in the Curripaco Indians, and was detected in settlements situated within the drainage of both the Río Orinoco and the upper Río Negro. Approximately 9% of the white settlers (colonos) harbored M. ozzardi, and 5% M. perstans. These results indicate that both M. perstans and M. ozzardi are endemic in the Comisaría del Guainía, and suggest that the focus of M. perstans may extend further into the South American continent along the Río Negro and its tributaries.  相似文献   
973.
Endothelial function is thought to be an important factor in the pathogenesis of atherosclerosis, hypertension and heart failure. In the 1990s, high-frequency ultrasonographic imaging of the brachial artery to assess endothelium-dependent flow-mediated vasodilation (FMD) was developed. The technique provokes the release of nitric oxide, resulting in vasodilation that can be quantitated as an index of vasomotor function. The noninvasive nature of the technique allows repeated measurements over time to study the effectiveness of various interventions that may affect vascular health. However, despite its widespread use, there are technical and interpretive limitations of this technique. State-of-the-art information is presented and insights are provided into the strengths and limitations of high-resolution ultrasonography of the brachial artery to evaluate vasomotor function, with guidelines for its research application in the study of endothelial physiology.  相似文献   
974.
INTRODUCTION AND OBJECTIVES: Coronary flow reserve (CFR) is impaired not only in ischemic heart disease, but also in cardiac diseases that may or may not course with heart failure. The aim of the present study was to determine if the severity of heart failure can influence CFR impairment. METHODS: Forty patients with non-ischemic heart disease and heart failure were studied 41 times. Four groups were established: 1. 10 patients in functional class III-IV; 2. 10 patients in functional class II not taking beta-blockers; 3. 11 patients in class II treated with carvedilol, and 4. 10 patients in class I. These patients had a history of heart failure and systolic dysfunction. Myocardial blood flow (MBF) was measured with positron emission tomography (PET) and N-13 ammonia at rest (r) and during adenosine triphosphate (ATP) infusion. RESULTS: MBF and CFR were significantly higher in group 4 (1.95 0.58 and 2.40 0.95 ml/min/g) than in group 1 (1.02 0.52 and 1.46 0.48 ml/min/g). CFR tended to be higher in groups 2 (1.73 0.72), and 3 (1.89 0.75) vs group 1. No significant correlation was found between CFR and the following variables: age, systolic blood pressure, ventricular mass index, ventricular volume indexes, and ejection fraction. CONCLUSIONS: Coronary microvascular function is impaired in non-ischemic heart failure, and the impairment is related to functional class, regardless of the underlying responsible heart disease.  相似文献   
975.
976.
Vasa previa is a rare condition, frequently lethal, in which fetal blood vessels coming from the placenta or the umbilical cord cross the entrance of the childbirth channel before presentation. The abnormal blood vessels are result of a velamentous cord insertion or a placental alteration. It happens in 1:3000 births, with a high perinatal mortality. A 16 years-old primigest patient, at 34.6 week of gestation, was admitted to the labor, which has a good evolution, without any complication. A male new born was obtained without hearth rate or vitality, Apgar scale 0-0, weight 2800 grams, who presented an umbilical cord rupture 3 centimeters from its abdominal insertion, no where the fetal blood vessels are unprotected. It is necessary an adequate prenatal care, diagnosis and accurate management, to avoid the mortality by this rare clinical entity.  相似文献   
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980.

Background

Hepatitis E virus (HEV) infection in patients with pre-existing liver disease has shown high morbidity and lethality. The consequences of HEV superinfection in patients with chronic hepatitis C virus (HCV) infection are not fully understood. This study aimed to evaluate the association between the presence of anti-HEV antibodies, liver cirrhosis, and insulin resistance.

Methods

A total of 618 patients chronically infected with HCV were included from three reference centers for viral hepatitis in São Paulo, Brazil. Presence of anti-HEV IgG was assessed by enzyme-linked immunosorbent assay (WANTAI HEV-IgG ELISA).

Results

The seroprevalence of anti-HEV in patients with cirrhosis was significantly higher than in patients without cirrhosis (13.2% vs 8%, OR = 1.74, p = 0.04). Seropositivity for anti-HEV, adjusted for sex, age, and HCV genotype showed an association trend with hepatic cirrhosis (aOR = 1.75, p = 0.059). Presence of HEV antibodies, adjusted for age, body mass index and cirrhosis, was shown to be independently associated with insulin resistance (aOR: 4.39; p = 0.045).

Conclusion

Patients with chronic hepatitis C are under risk of hepatitis E virus superinfection in Brazil. The trend toward association between cirrhosis and previous HEV infection suggests that it may accelerate liver fibrosis in patients with chronic hepatitis C. In addition, previous infection by HEV is independently associated with insulin resistance in the studied population, which may be an extra-hepatic manifestation of hepatitis E that persists after resolution of the active infection, and may contribute to fibrosis progression.  相似文献   
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