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Atrophy of salivary glands may occur by ductal obstruction caused by calculus, infection or neoplastic processes, or as consequence of systemic diseases and aging. In the present work, we have used histochemical methods to study the expression of elastic and collagen fibers during experimental atrophy of the submandibular gland of mice. Glandular atrophy was accompanied by a rapid increase in collagen deposition in both septal and intralobular regions. The expression of elastic fibers was not significantly altered during atrophy; a discrete increase of elastic fibers was noted only around ductal structures. The results showed that experimental ductal obstruction is a useful in vivo model to study molecular events that take part in the remodeling of the extracellular matrix during atrophy of salivary glands.  相似文献   
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Imipenem, a new carbapenem antibiotic shows an extremely broad spectrum of antibacterial activity for almost all Gram-negative and Gram-positive aerobic and anaerobic bacteria. It is stable to beta-lactamases and shows a high affinity for PBP 2. The changes in morphology and ultrastructure caused by the antibiotic on Ps. aeruginosa confirm that imipenem acts by binding primarily to PBP 2, resulting in irregular and round shaped cells, and later during treatment to PBP 1 with cellular lysis. The involvement of PBP 1 is also demonstrated by the fast bactericidal kinetics on Ps. aeruginosa, E. coli and Staph. aureus.  相似文献   
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To assess the magnitude and nature of interpersonal violence resulting in hospitalisation of children and to identify subgroups at risk of repeat hospital admissions, a population-based, retrospective study of all violence hospitalisations in Western Australia for children aged 9 years or less was undertaken, using the 1990–2004 linked data retrieved from the Western Australian Mortality Database and the Hospital Morbidity Data System.
Of the 747 patients aged <10 years incurring 834 hospitalisations for the consequences of violence during the study period, 570 (76%) were less than 4 years of age. A total of 43 deaths from violence were recorded and 74 (9%) patients were admitted for more than one episode of violence. Victims aged 0–4 years from rural (hazard ratio [HR] = 2.72; 95% confidence interval [CI] 1.35, 5.43) and remote parts (HR = 2.79; 95% CI 1.25, 6.25) of the state were at increased risk of a subsequent admission for violence compared with those residing within the metropolitan area. Indigenous children aged 5–9 years were significantly more likely (HR = 3.57; 95% CI 1.14, 11.13) to incur a second hospitalisation for violence than their non-Indigenous counterparts. The identification of young victim subgroups at high risk of repeat hospitalisations is important for developing intervention strategies to reduce the burden of interpersonal violence. Young children aged 0–4 years living in rural and remote locations and Indigenous children aged 5–9 years should be specifically targeted for attention.  相似文献   
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A child had the characteristic clinical and EEG pattern of migrating partial seizures in infancy with left temporal lobe atrophy, hippocampal sclerosis and cortical-subcortical blurring.Seizures were drug-resistant, with recurring episodes of status epilepticus. The child developed microcephaly with arrest of psychomotor development. Focal brain lesions, in the context of migrating partial seizures, have not been previously reported.[Published with video sequences].  相似文献   
7.
Distributional Issues in the Analysis of Preventable Hospitalizations   总被引:1,自引:0,他引:1  
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OBJECTIVE: To evaluate the prevalence and clinico/prognostic significance of the presence of pre-invasive lesions in patients resected for primary lung neoplasm. METHODS: From 1993 to 2002, 1090 patients received resection for primary lung carcinomas. Of these, 73 presented an associated pre-invasive lesion in the surgical specimen distant from the primary tumour. Classification of pre-invasive lesions included Atypical Adenomatous Hyperplasia (AAH); Carcinoma In Situ (CIS) either diffuse or at the bronchial resection margin; Diffuse Idiopathic Pulmonary Neuroendocrine Cell Hyperplasia (DIPNECH). Correlation between the presence of pre-invasive lesion and the following variables were calculated by logistic regression analysis: sex, age, median tumour size, histology, histologic differentiation, histologic evidence of invasiveness (vascular and perineural invasion), peritumoural lymphocytic infiltrate, pTNM, lobe location, history of previous malignancy. Survival rates were computed using Kaplan-Meier method and survival differences with the total patient population of resected lung carcinomas were tested using the log-rank method. RESULTS: There were 28 AAH, 42 CIS (5 at the bronchial resection margin) and 3 DIPNECH. Histology of the primary tumor included bronchioloalveolar carcinoma (9 patients), adenocarcinoma (19), squamous cell carcinoma (39), typical carcinoid tumour (3) and adenosquamous carcinoma (3). Overall prevalence of pre-invasive lesion was 6.7%. A strong correlation was found between the presence of AAH and the co-existence of either adenocarcinoma, bronchioloalveolar carcinoma or mixed adenocarcinoma-containing tumours (P = 0.00002) between CIS and squamous cell carcinoma (P = 0.009) and between DIPNECH and carcinoid tumours (P = 0.001). No significant correlation was found between the presence of any type of pre-invasive lesion and sex, age, median tumour size, histologic differentiation, histologic evidence of invasiveness, pTNM, lobe location and history of previous malignancy or the probability to develop a second primary lung carcinoma in the remaining lobe(s) after resection. Survival rates in the patients with AAH and CIS were not significantly different from those of patients without pre-invasive lesion (P = 0.3 and P = 0.1). CONCLUSIONS: Associated pre-invasive lesions in patients resected for primary lung neoplasms are not infrequent. AAH is associated with adenocarcinoma, CIS with squamous cell carcinoma, DIPNECH with typical carcinoid tumours. Our experience indicates that in these patients histology, stage distribution and survival do not differ from the total population of resected patients with lung tumors.  相似文献   
9.
Eating disorders have generally been considered uncommon among ethnic minorities. However, there are data that suggest bulimia nervosa may not be all that rare in some minority groups. Furthermore, emerging data on binge eating disorder (BED) have indicated high rates in some ethnic groups, and these data prompt reconsideration of the view that minority populations are protected from eating disorders. The current report reviews data on bulimia nervosa and BED in ethnic minority groups. Ramifications of a broader diversity of affected individuals on our understanding of eating disorders will be addressed, and directions for further research will be discussed.  相似文献   
10.
Hemorrhagic vascular complications of endoscopic transsphenoidal surgery.   总被引:1,自引:0,他引:1  
Two hundred and fifty consecutive patients operated on by an endoscopic endonasal transsphenoidal approach were retrospectively analyzed in order to evaluate hemorrhagic vascular complications occurring during or after the surgical procedure and their appropriate management. Vascular complications of endoscopic transsphenoidal surgery are identical to those of a microsurgical transsphenoidal approach. Damage to the sphenopalatine artery and to the internal carotid artery (ICA), which are the most frequent vascular troubles, may require technical tricks because of some aspects connected to the approach itself and of the physical properties of the endoscope. Furthermore, the progress in interventional neuroradiology in the last decades offers new solutions in respect to the past, where the use of the surgical microscope was already a tremendous progress. The anatomic substrate of each complication is discussed, along with the peculiar surgical details related to it.  相似文献   
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