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排序方式: 共有628条查询结果,搜索用时 15 毫秒
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Vito Briganti Lucia Oriolo Vitaliano Buffa Salvatore Garofalo Sebastiano Cavallaro Alessandro Calisti 《European journal of cardio-thoracic surgery》2005,28(1):11-15
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
3.
MY Mancao LJ Sindel PH Richardson FM Silver 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(1):118-120
Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup. 相似文献
4.
Lead shielding in contact with the patient's skin is often encountered in radiotherapy with electron beams. The influence of the lead shielding on dose distributions in the patient cannot fully be assessed using modern treatment planning systems. In this work the problem of quantifying the effect of lead shielding on dose distributions is addressed. Monte Carlo dose calculations were performed in a half-blocked water phantom shielded by lead, using a realistic model for the fluence of an electron linear accelerator. Electron beam energies of 6-20 MeV and lead thicknesses of 1-7 mm are used for 10 x 10 cm2 and 5 x 5 cm2 fields. The perturbation of the particle fluence and dose distributions in water introduced by the lead shielding is quantified. The effect of oblique electron beams on the dose perturbation is shown. A fictitious clinical example, the shielding of an eye in electron beam treatment, is used to demonstrate the usefulness of Monte Carlo based treatment planning algorithms that can incorporate the effects of lead shielding. 相似文献
5.
Carlo Capella Cesare Bordi Guido Monga Roberto Buffa Paolo Fontana Silvana Bonfanti Gianni Bussolati Enrico Solcia 《Virchows Archiv : an international journal of pathology》1978,377(2):111-128
Summary 10 cases of thyroid medullary carcinoma (TMC) have been studied ultrastructurally and histochemically. Well differentiated calcitonin-producing C cells were present in all tumours, being prevalent in 9 cases. 5-Hydroxytryptamine (5HT) storing cells were found in two cases, somatostatin immunoreactive cells in at least 5 cases and ACTH-immunoreactive cells in 4 cases. Ultrastructurally, at least 3 types of apparently non-C cells were observed. Type 1 cells with large, poorly osmiophilic granules resembling those of gastroenteropancreatic D cells, were present in 6 cases; they appeared to correlate well with somatostatin immunoreactive cells. Type 2 cells with large osmiophilic granules were found in 5 cases; they resembled ACTH-MSH cells of the human pituitary and may correspond to the ACTH-immunoreactive cells of light microscopy. Type 3 cells with small granules and an unknown function were found in 6 cases, always in scarce number. It is concluded that TMC, although mainly made up of C cells, usually contains large proportions of other endocrine cell types.Supported in part by grant N. 75.00630.04 from the Italian National Research Council (C.N.R.). P.F. is a fellow of the Fondazione Anna Villa Rusconi, Varese 相似文献
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Somatotyping is an effective technique for the study of anthropometric variations and body composition in elderly subjects, even though it has not often been used in this field. The present study was conducted on a sample of 280 healthy Sardinians (134 men and 146 women) of age 60-89 years, subdivided into three age classes (60-69 years; 70-79 years; and 80-89 years). Somatotypes were computed according to Carter and Heath (Somatotyping-Development and Applications. Cambridge, England: Cambridge University Press; 1990). The results show a dominance of the endo- and mesomorphic components in the elderly subjects, with less development of ectomorphy than in younger individuals. In a comparison with other populations, our sample shows strong development of endomorphy and especially of mesomorphy, while ectomorphy values are generally low. Age-related variations are significant in both sexes and consist in a progressive reduction of the endomorphic component, particularly in the 80-89-year class (endomorphy in the three age classes: 6.4, 6.1, and 5.3 in men; 8.1, 7.8, and 6.8 in women). The mesomorphic component is characterized by stability (age variations: 6.4, 6.4, and 5.9 in men; 6.3, 6.4, and 6.3 in women) and the ectomorphic component by a slight increase (age variations: 0.5, 0.6, and 0.8 in men; 0.4, 0.3, and 0.5 in women). Sex differences are significant and especially large for the endomorphic component, with generally higher values in women. The sexual dimorphism tends to decrease with age. The results are discussed with regard to the biology of aging, with emphasis on the potential application of somatotype to studies of the elderly population. 相似文献
8.
Granata C Buffa P Di Rovasenda E Mattioli G Scarsi PL Podesta E Dodero P Jasonni V 《Journal of pediatric surgery》1999,34(12):1836-1838
BACKGROUND/PURPOSE: Vesico-ureteric reflux (VUR) is a common problem in children with neuropathic bladder. Lesser-degree VUR may be manageable by intermittent catheterization or by anticholinergics, but higher grades usually require surgical treatment. If left untreated, two thirds of such patients may experience deterioration of the upper renal tracts. The aim of this study was to compare the results of the STING (Subureteric Teflon Injection) technique with surgical ureteric reimplantation as treatment for VUR in neuropathic bladder. METHODS: From January 1981 to December 1996, 58 children with NB (81 ureters) were treated for VUR. STING and Cohen ureteroneocystotomy were performed in 40 and 41 ureters, respectively. Mean age was 4.5 years (STING) and 5.1 years (Cohen). RESULTS: Twenty-nine of 40 refluxing ureters (72.5%) were cured by STING, whereas Cohen eradicated reflux in 39 of 41 ureters (95.5%). No complications were observed in either group. All the ureters in which STING failed were treated successfully by Cohen ureteroneocystostomy. The 2 ureters still refluxing after surgical reimplantation were cured successfully by a single STING. The mean follow-up was 6.8 years in the Cohen group and 4.8 years in the STING group. During follow-up, no recurrence was observed in patients cured by open reimplantation. In the STING group, 2 previously cured ureters showed recurrence of VUR: both were treated successfully by a further STING. CONCLUSIONS: Open ureteral reimplantation is more effective than STING in correcting VUR in children with neuropathic bladder dysfunction. Nevertheless, the good success rate, the relative technical simplicity, outpatient nature, and rapid recovery point to STING as a safe and effective procedure for the initial treatment of VUR. Failure of STING does not preclude a successful open operation. 相似文献
9.
Francesca M Buffa S?ren M Bentzen Frances M Daley Stanley Dische Michele I Saunders Paul I Richman George D Wilson 《Clinical cancer research》2004,10(11):3745-3754
PURPOSE: Identification of factors that assist prediction of tumor response to radiotherapy may aid in refining treatment strategies and improving outcome. Possible association of molecular marker expression profiles with locoregional control of head and neck squamous cell carcinoma was investigated in a randomized trial of conventional versus continuous hyperfractionated accelerated radiotherapy (CHART). EXPERIMENTAL DESIGN: Tumor material was obtained from 402 patients. Immunohistochemistry was used to assess Ki-67, CD31, p53, Bcl-2, and cyclin D1 expression. A hierarchical clustering algorithm with a Bayesian information criterion was used to group tumors with similar marker expression; resulting expression profiles were then compared in terms of their difference in outcome after CHART and conventionally fractionated radiotherapy. RESULTS: Molecular marker profile was an independent prognostic factor for locoregional control. This was confirmed in multivariate analysis, including clinical variables such as tumor and nodal status, primary site, histological grade, age, and gender (P < 0.001 and P = 0.006 for local and nodal relapse, respectively). In particular, Bcl-2-positive tumors responded significantly better than average in both arms of the trial. Tumors negative for p53- and Bcl-2, with high and randomly patterned Ki-67 expression, responded worse than average with no benefit from CHART. Tumors with similarly negative p53 and Bcl-2, but low Ki-67 staining, with an organized pattern, benefit significantly from CHART schedule. CONCLUSIONS: This study demonstrates the potential of molecular profiles to predict radiotherapy response of head and neck squamous cell carcinoma and for treatment stratification. Distinct expression profiles correlate with three distinct clinical phenotypes, including good locoregional control, poor locoregional control, and an outcome strongly dependent upon fractionation schedule. 相似文献
10.
This review correlates the imaging findings and histological appearances seen in chordomas in a series of patients presenting at our institution, together with a published literature review. A parallel presentation of photographs of imaging findings and microscopic histological findings is made, with the aim being to enhance recognition of this uncommon but clinically significant entity. 相似文献