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Abstract: This study was carried out to determine the underestimation rate of carcinoma upon surgical biopsy after a diagnosis of flat epithelial atypia and atypical ductal hyperplasia and 11‐gauge vacuum‐assisted breast biopsy. A retrospective review was conducted of 476 vacuum‐assisted breast biopsy performed from May 2005 to January 2007 and a total of 70 cases of atypia were identified. Fifty cases (71%) were categorized as pure atypical ductal hyperplasia, 18 (26%) as pure flat epithelial atypia and two (3%) as concomitant flat epithelial atypia and atypical ductal hyperplasia. Each group were compared with the subsequent open surgical specimens. Surgical biopsy was performed in 44 patients with atypical ductal hyperplasia, 15 patients with flat epithelial atypia, and two patients with flat epithelial atypia and atypical ductal hyperplasia. Five cases of atypical ductal hyperplasia were upgraded to ductal carcinoma in situ, three cases of flat epithelial atypia yielded one ductal carcinoma in situ and two cases of invasive ductal carcinoma, and one case of flat epithelial atypia/atypical ductal hyperplasia had invasive ductal carcinoma. The overall rate of malignancy was 16% for atypical ductal hyperplasia (including flat epithelial atypia/atypical ductal hyperplasia patients) and 20% for flat epithelial atypia. The presence of flat epithelial atypia and atypical ductal hyperplasia at biopsy requires careful consideration, and surgical excision should be suggested.  相似文献   
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A patient with well-defined acute HIV infection who developed concomitant pulmonary tuberculosis during the retroviral acute syndrome is reported here. In this patient high levels of T-regulatory cells (Tregs) and a low proliferation response to M. tuberculosis were initially detected, which normalized throughout follow-up. This case calls for the consideration of tuberculosis in patients in the early stages of HIV, and emphasizes the need for further study of the potential causal relationship between Treg cells and the risk of TB reactivation in HIV patients.  相似文献   
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Arrestins (Arrs) are ubiquitous regulators of the most numerous family of signaling proteins, G protein-coupled receptors. Two models of the Arr-receptor interaction have been proposed: the binding of one Arr to an individual receptor or to two receptors in a dimer. To determine the binding stoichiometry in vivo, we used rod photoreceptors where rhodopsin (Rh) and Arr are expressed at comparably high levels and where Arr localization in the light is determined by its binding to activated Rh. Genetic manipulation of the expression of both proteins shows that the maximum amount of Arr that moves to the Rh-containing compartment exceeds 80%, but not 100%, of the molar amount of Rh present. In vitro experiments with purified proteins confirm that Arr "saturates" Rh at a 1:1 ratio. Thus, a single Rh molecule is necessary and sufficient to bind Arr. Remarkable structural conservation among receptors and Arrs strongly suggests that all Arr subtypes bind individual molecules of their cognate receptors.  相似文献   
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BACKGROUND: Recent data indicate that fungi may contribute to increased severity of asthma. OBJECTIVES: To determine the prevalence of allergy to 15 mold allergens among patients hospitalized because of exacerbation of asthma and to evaluate the relationship between the severity of the disease and allergy to particular molds. METHODS: Skin prick tests with standard aeroallergens of airborne allergens, including grass, tree, Dermatophagoides pteronyssinus, Dermatophagoides farinae, feather, and cat and dog fur, and a panel of mold allergens, including Alternaria, Cladosporium, Aspergillus, Penicillium, Trichothecium, Chaetomium globosum, Epicoccum, Epidermophyton, Helminthosporium, Aureobasidium pullulans, Rhizopus nigricans, Fusarium, Mucor, Merulius lacrymans, and yeast mix, were performed in 105 asthmatic patients and 30 controls. RESULTS: Positive skin prick test results were found in 98% of asthmatic patients and 66% of controls. Sensitivity to A pullulans was significantly associated with more severe asthma (odds ratio, 1.4; 95% confidence interval, 1.09-1.75; P = .006). Sensitization to Helminthosporium was associated with an increased number of asthma exacerbations that required hospitalization (17% vs 38%; chi2 test P = .03). CONCLUSION: Sensitization to A pullulans is a risk factor for severe asthma. Sensitization to Helminthosporium may be related to asthma exacerbation that requires hospitalization.  相似文献   
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The aim of the study was to compare the treatment regimen of three natural surfactants of different extraction and formulation (Alveofact [Surfactant A = SA], Poractant [Surfactant B = SB] and Beractant [Surfactant C = SC]) in neonatal respiratory distress syndrome (RDS). Premature infants of /=0.3 were randomly assigned to receive at least two doses of SA, SB or SC (100 mg/kg per dose). Infants who remained dependent on artificial ventilation with a FiO2 >/=0.3 received up to two additional doses. There were no differences among the groups regarding the necessity for more than two doses. The SA and the SB groups spent fewer days on a ventilator (p-value SA/SB 0.7, SA/SC 0.05, SB/SC 0.043) compared with the SC group, needed fewer days of oxygen administration (p-value SA/SB 0.14, SA/SC 0.05, SB/SC 0.04) and spent fewer days in hospital (p-value SA/SB 0.65, SA/SC 0.04, SB/SC 0.027). There were no statistically significant differences in the incidence of mortality, chronic lung disease, air leaks, necrotising enterocolitis, retinopathy of prematurity and intraventricular haemorrhage among the three groups. CONCLUSION: The Alveofact and Poractant groups spent fewer days on the ventilator, needed fewer days of oxygen administration and spent fewer days in hospital compared with the Beractant group but no differences were observed among the three groups with regards to mortality and morbidity.  相似文献   
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