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41.
An increased prevalence of bronchial hyper-responsiveness (BHR) has been demonstrated in children from a general population, and in non-asthmatic adults with allergic rhinitis. Thus, also children with allergic rhinitis are expected to be at higher risk of BHR. We evaluated the prevalence of BHR in a sample of non-asthmatic children with allergic rhinitis by means of the methacholine (Mch) bronchial challenge, and by monitorizing the airway patency using the daily peak expiratory flow variability (PEFv). Fifty-one children (ranged 6–15 years of age) with allergic rhinitis, ascertained by skin prick test to inhalant allergens, underwent a 14-day peak expiratory flow monitoring, and a Mch bronchial provocation challenge. Thirty healthy children matched for age, and sex served as control group. Thirty-one children in the rhinitis group (61%), and six (20%) in the control group were Mch+ (Mch provocative dose causing a 20% fall of forced expiratory volume in 1 s respect to baseline <2250  μ g, equivalent to 11.50  μ mol). In rhinitic children the PEFv did not significantly differ between Mch+ and Mch− subjects, but the total serum immunoglobulin E (IgE) were higher among Mch+. The persistent form of rhinitis was significantly associated to Mch positivity. Non-asthmatic children with allergic rhinitis displayed a high prevalence of BHR. The BHR was significantly associated with persistent rhinitis and with higher total IgE levels. Nevertheless, the spontaneous changes in airway patency, as expressed by PEFv, were within normal limits both in Mch+ and Mch− children.  相似文献   
42.
BACKGROUND: Nitrate therapy can induce ischemic preconditioning with a consequent increase in tolerance to ischemia. In the context of acute coronary syndromes (ACS), nitrates may result in a different presentation. with greater protection. OBJECTIVES: To investigate in a population of patients with ACS whether previous chronic use of nitrates results in a different presentation of ACS. METHODS: We studied 287 patients (65 +/- 13 years, 66% male) admitted to our department in the first six months of 2005 with ACS (with and without ST-segment elevation). Of these, 8% were under nitrate therapy at the time of admission. In this group, 27% presented ACS without ST-segment elevation, while in the group without nitrates this value was 58% (p = 0.005). By univariate analysis, the use of nitrates was a predictor of the preferential occurrence of non-ST-segment elevation ACS (OR 0.27, 95% CI 0.10-0.71). After correction for the potential influence of variables (age, gender, previous revascularization and smoking) by multivariate logistic regression, nitrate therapy remained a borderline predictor of clinical presentation as non-ST-segment elevation ACS (OR 0.37, 95% CI 0.13-1.04, p = 0.059). CONCLUSIONS: Previous use of nitrates was associated with a tendency to present as non-ST-segment elevation ACS. This finding may be explained by the hypothesis that nitrates induce pharmacological preconditioning, reducing the transmural extent of myocardial infarction.  相似文献   
43.
OBJECTIVE: A Tracheomalacia complicates 11-33% of cases of Oesophageal Atresia with distal Tracheo-Oesophageal Fistula. The lesion generally involves only the thoracic segment of the trachea, and it has close anatomical relationships with the mediastinal structures, specially with the aortic arch. We therefore tried to define the most important morphotypes of tracheobronchial malacia by using dynamic fiberoptic bronchoscopy (DFB) and spiral multilayer computed tomography (CT). METHODS: Between 1999 and 2003 we studied 40 children from two different institutions who had been operated on at birth for oesophageal atresia. All patients were been submitted to DFB, and the positive cases underwent examination by CT with an iodinated contrast medium. CT angiographic images of great vessels and multiplanar and three-dimensional images of the airways (virtual broncoscopy and broncography) were obtained for morphological evaluation. RESULTS: Twenty-five patients (62%) tested positive for malacia using DBF and all were also confirmed by CT study. In 11 cases (46%), the malacia was located at the thoracic section of the trachea, which was occluded by compression of the aorto-innominate complex. A simple intrinsic tracheomalacia without any vascular compression was present in eight cases (33%), while in five cases (21%), the malacia was complex. CONCLUSIONS: A correct morphological analysis of the malformed segment permitted 'tailored surgery' for each individual patient, allowing us to take account of the type of malacia, its length, and the compressive action exercised by the mediastinal great vessels.  相似文献   
44.
OBJECTIVE: Our purpose was to investigate immunosuppressive acidic protein in the prognostic characterization of advanced ovarian cancer. STUDY DESIGN: Serum levels of immunosuppressive protein were prospectively measured in 80 patients with untreated ovarian carcinoma. To evaluate the prognostic significance of immunosuppressive acidic protein levels, cutoff points were studied every 50 μg/ml between 450 and 1350 μg/ml. RESULTS: Pretreatment immunosuppressive acidic protein levels were not significantly associated with stage, histotype, grade of differentiation, postoperative residual tumor, and response to chemotherapy. The most significant association with survival was observed at a cutoff value of 1100 μg/ml (p = 0.0089). In the univariate analysis for overall survival, International Federation of Gynecology and Obstetrics stage and immunosuppressive acidic protein status were found to have a role in predicting ovarian cancer prognosis. In the multivariate analysis only immunosuppressive acidic protein status was significantly associated with survival. A statistical correlation was found between serum levels and overall survival (p = 0.0104, χ2 6.56), including immunosuppressive acidic protein as a continuous variable. CONCLUSION: Our data suggest that immunosuppressive acidic protein assay is a potentially useful tool in the prognostic characterization of advanced ovarian cancer. (Am J Obstet Gynecol 1996;175:1606-10.)  相似文献   
45.
We identified large-scale heteroplasmic mitochondrial DNA (mtDNA) rearrangements in a 50–year-old woman with an adult-onset progressive myopathy. The predominant mtDNA abnormality was a 21.2–kb duplicated molecule. In addition, a small population of the corresponding partially deleted 4.6–kb molecule was detected. Skeletal muscle histology revealed fibers that were negative for cytochrome c oxidase (COX) activity and had reduced mtDNA-encoded COX subunits. By single-fiber polymerase chain reaction analysis, COX-negative fibers contained a low number of wild-type or duplicated mtDNA molecules (ie, nondeleted). In situ hybridization demonstrated that the abnormal fibers contained increased amounts of mtDNA compared with normal fibers and that most of the genomes were deleted. We concluded that deleted mtDNA molecules were primarily responsible for the phenotype in this patient.  相似文献   
46.
The results of panoramic diagnostic microhysteroscopy are reported in 284 patients with sterility or infertility problems. In 33.5% of the patients, microhysteroscopy revealed uterine pathology; in the majority of cases they were pathologies which are unanimously recognized as being causes of sterility, while in others there were pathologies whose role infertilities is still unclear. There was a good correlation between microhysteroscopy and histology in cases of endometrial hyperplasia and of endometritis, whereas in cases of endometrial polyps and functional diagnosis of the endometrium, the correlation was less satisfactory. Although it is not possible at present to draw definite conclusions about the real value and advantages of microhysteroscopy in the diagnosis of female infertility, we are convinced that it is of great use and that it should be at the basis of any investigation involving the infertile woman.  相似文献   
47.
Colorectal surgery is still associated with a significant morbidity and mortality rate, mostly related to suture failure. We have carried out a randomized experimental study in dogs on colonic anastomoses exposed to a number of anastomotic risk situations. A total of 42 dogs was used. They were divided into three study groups (control, occlusion and diverticulitis), with and without an endoluminal tube. The aim was to assess the efficacy of the endoluminal prosthesis using clinical and radiological assessment of anastomotic healing. Pre- and post-anastomotic intraluminal pressures were also measured to determine whether these might be a factor in suture failure. There were significant differences in suture failure in animals in which the endoluminal tube was used. Mean duration of placement was 10.5 days. In the colon healing study, no significant differences were found between the groups in the pathological examination or in the assay of hydroxyproline content. The presence of the endoluminal tube may increase the maximum pressure applied on the colon wall. No significant differences were found in the intracolonic pressure differentials between the different groups or after the inclusion of the endoluminal prosthesis. The results obtained establish the efficacy of the endoluminal prosthesis in protecting the colonic anastomosis, and could be a valuable technique in colonic anastomoses with a high risk of suture dehiscence.  相似文献   
48.
The immunohistochemical occurrence of the neurotrophin (NT) proteins nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-4 (NT-4), and neurotrophin-3 (NT-3) is shown in the pre-term newborn, infant, and adult human post-mortem cerebellum. The NT-like immunoreactive structures were unevenly distributed and showed regional differences among cerebellar lobules and folia. NGF-, NT-4-, and NT-3-positive neuronal perikarya were observed in all specimens examined. At variance with the other neurotrophins, the BDNF antiserum labelled neuronal cell bodies only in newborn life and infancy, as well as extensive nerve fibre systems, whose density increased with age. The NT-antibodies, tested by Western blot on human cerebellum homogenates, revealed immunoreactive bands corresponding to proteins of heterogenous molecular weight. The results obtained provide a first demonstration of the tissue localization of the NTs in the human cerebellum from perinatal to adult age, thus suggesting their involvement in the development, differentiation and maintenance of the cerebellar connectivity. Codistribution of the four NTs or sets of them was observed in cortical and deep nuclei neurons. Multiple trophic roles for NTs, encompassing the classic target-derived and local mechanisms of support, are envisaged as significant in development, differentiation, and maintenance of the human cerebellar connectivity.  相似文献   
49.
Serum immunoglobulins and the activity of natural killer (NK) cells of 50 epileptic patients (eight with idiopathic generalized epilepsy and 42 with cryptogenic partial epilepsy) and 28 controls have been studied. The values of IgA, IgG and IgM were the same-in patients and controls. The NK activity in controls was linearly related to the effector-to-target ratio, but this linear relationship was not observed in epileptic patients. The cytotoxic activity of NK cells at the lowest effector-to-target ratio was significantly greater in patients than in controls. This increase was observed in each therapy group. Our results seem to confirm a disturbance of the immune system in epileptic patients and suggest that this modification of cellular immunity is not a drug effect but is related to the illness itself.  相似文献   
50.
Haemophilia A: molecular insights.   总被引:1,自引:0,他引:1  
Haemophilia A is the most common inherited bleeding disorder caused by defects in the F8C gene that encodes coagulation factor VIII. This X-linked recessive disorder occurs in approximately 1:5000 males. Haemophilia A is diagnosed based on normal prothrombin time, altered activated partial thromboplastin time and reduced factor VIII activity in plasma. Carrier females are usually asymptomatic and can be identified only by molecular analysis. The most frequent mutations in F8C are intron 22 and 1 inversions, which occur in approximately 50% and 5% of patients, respectively, with a severe phenotype. Large gene deletions are observed in approximately 5% of alleles from patients with severe haemophilia A. The remaining severe cases and all moderate and mild cases result from numerous point mutations and small insertions/deletions, which are de novo mutations in one-third of cases. Thus, molecular diagnosis of carrier status and prenatal diagnosis in families without intron 22 or 1 inversions is based on scanning techniques or gene sequencing. When the disease-causing mutation cannot be identified, molecular diagnosis is performed by linkage analysis of several DNA polymorphic markers linked to F8C. Given the clinical heterogeneity among haemophilic patients, many groups, including our own, have examined the relationships between prothrombotic gene variants and haemophilic phenotype to investigate whether prothrombotic gene variants modify clinical expression of the disease.  相似文献   
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