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91.
Parasympathetic innervation of nasal mucosa plays an important role in the pathogenesis of chronic hypertrophic non-allergic rhinitis (C.H.N.A.R.). The present study investigated the effect of Vidian nerve stimulation and resection on the histamine contents and on the morphological pattern in mucosal samples of patients with C.H.N.A.R. Vidian nerve stimulation determines a significant decrease in histamine content in the samples examined; microscopical observations showed significant variations in the glandular, stromal and vascular components.The changes indicate an enhanced secretory activity, intensive vasodilatation and active degranulation of mast cells, which were significantly decreased in number in the samples obtained after 90 sec of stimulation.The neurectomy of the Vidian nerve resolves quite completely the clinical symptomatology and in parallel decreases the mucosal histamine contents, which are increased in patients with C.H.N.A.R. before the operation in comparison with the normal controls.  相似文献   
92.
The influence of age and mammary gland differentiation on the incidence of tumors induced by 7,12-dimethylbenz(a)anthracene (DMBA) was studied by correlating the development of the mammary glands of 20-180-day-old, virgin Sprague-Dawley rats with the number and type of tumors induced by DMBA administered at those various ages. The number of terminal end buds (TEBs), terminal ducts (TDs), and alveolar buds (ABs)/sq mm and their DNA-labeling indices (DNA-LI) were determined. Highest density of TEB occurred when the rats were 20 days old, decreasing thereafter. DNA-LI ranged between 25.2 and 29 in TEB of rats aged 30-55 days, which was coincident with the highest incidence of carcinomas. With aging, the number of TEBs and their DNA-LI decreased and the number of TDs and ABs increased, although with a low DNA-LI, which correlated with a lower incidence of carcinomas and higher incidence of benign lesions.  相似文献   
93.
Seventy-six hearts were studied having no direct communication between the right atrium and the ventricular mass. The different cardiac chamber combinations producing so-called "tricuspid atresia" were considered. The nature of the atrioventricular valve atresia, the morphology of the ventricular mass, the size and position of the interventricular communication, the ventriculoarterial connection, and the presence of subarterial outflow tract obstruction were all analyzed. The majority of cases were of the "classical" type, i.e., absent right atrioventricular connection with the left atrium connected to the left ventricle. In another group there was absence of the right atrioventricular connection but the left atrium drained into the morphologically right ventricle, which was left-sided. In a third group both atrial chambers connected with the ventricular mass but some structure, an imperforate valve or muscular partition, completely blocked the flow pathway through the right side of the heart. All the hearts described are candidates for the Fontan procedure with either an atrioventricular or an atriopulmonary conduit. The surgical options would not be affected by the observed variability at the atrioventricular junction but would be dictated by the feasibility of incorporating the subpulmonary ventricle within the pulmonary circulation.  相似文献   
94.
Altered circulating levels of free fatty acids (FFAs), namely short chain fatty acids (SCFAs), medium chain fatty acids (MCFAs), and long chain fatty acids (LCFAs), are associated with metabolic, gastrointestinal, and malignant diseases. Hence, we compared the serum FFA profile of patients with celiac disease (CD), adenomatous polyposis (AP), and colorectal cancer (CRC) to healthy controls (HC). We enrolled 44 patients (19 CRC, 9 AP, 16 CD) and 16 HC. We performed a quantitative FFA evaluation with the gas chromatography–mass spectrometry method (GC–MS), and we performed Dirichlet-multinomial regression in order to highlight disease-specific FFA signature. HC showed a different composition of FFAs than CRC, AP, and CD patients. Furthermore, the partial least squares discriminant analysis (PLS-DA) confirmed perfect overlap between the CRC and AP patients and separation of HC from the diseased groups. The Dirichlet-multinomial regression identified only strong positive association between CD and butyric acid. Moreover, CD patients showed significant interactions with age, BMI, and gender. In addition, among patients with the same age and BMI, being male compared to being female implies a decrease of the CD effect on the (log) prevalence of butyric acid in FFA composition. Our data support GC–MS as a suitable method for the concurrent analysis of circulating SCFAs, MCFAs, and LCFAs in different gastrointestinal diseases. Furthermore, and notably, we suggest for the first time that butyric acid could represent a potential biomarker for CD screening.  相似文献   
95.
Cow’s milk allergy (CMA) is one of the most common food allergies in infants, and its prevalence has increased over recent years. In the present paper, we focus on CMA as a model of food allergies in children. Understanding the diagnostic features of CMA is essential in order to manage patients with this disorder, guide the use of an elimination diet, and find the best moment to start an oral food challenge (OFC) and liberalize the diet. To date, no shared tolerance markers for the diagnosis of food allergy have been identified, and OFC remains the gold standard. Recently, oral immunotherapy (OIT) has emerged as a new therapeutic strategy and has changed the natural history of CMA. Before this, patients had to strictly avoid the food allergen, resulting in a decline in quality of life and subsequent nutritional, social, and psychological impairments. Thanks to the introduction of OIT, the passive approach involving rigid exclusion has changed to a proactive one. Both the heterogeneity in the diagnostic process among the studies and the variability of OIT data limit the comprehension of the real epidemiology of CMA, and, consequentially, its natural history. Therefore, well-planned randomized controlled trials are needed to standardize CMA diagnosis, prevention, and treatment strategies.  相似文献   
96.
BackgroudCurrent evidence supports the use of cemented hemiarthroplasty for treatment of intracapsular femoral neck fractures since it is associated with a lower risk of implant-related complications. However, many medical centers employ the cementless technique for the frail elderly population because it is faster and has lower cardiovascular risks and perioperative mortality. This observational study reports the outcomes of cementless bipolar hemiarthroplasty for intracapsular femoral neck fractures in patients aged 80 years and older.MethodsA total of 424 patients (female, 77.1%) with a mean age of 86.9 years were operated for intracapsular femoral neck fractures between January 2009 and December 2017. Of those, 66.7% had an American Society of Anaesthesiologists (ASA) score of 3 or more. All operations were performed with the posterolateral surgical approach and all patients received a cementless stem. Intraoperative and perioperative values and in-hospital outcomes were evaluated, and clinical and radiographical follow-up was done at 40 days, 90 days, and when possible between 5 months and 12 months postoperatively. Multivariate analysis was performed to evaluate if there were factors affecting mortality.ResultsThe mean operative time was 50 minutes. There were no deaths intraoperatively. Intraoperative periprosthetic fractures occurred in 2.1% of the cases with 66.7% of them fixed through cerclage wires intraoperatively. The median length of hospitalization was 11 days (interquartile range, 8.75–15) and 2.4% of patients died while in hospital after surgery. Approximately 91.5% of patients presented with perioperative anemia. Only 1.9% of the complications were related to the implant, 62.5% of which were dislocations. More than 90% of patients were ambulatory either autonomously or with support at each follow-up assessment. Age, male sex, and higher ASA score were related to increased mortality.ConclusionsDespite some limitations, this observational study underlines that a cementless femoral stem of modern design can give good clinical outcomes, thus being an appropriate solution especially for the frail elderly.  相似文献   
97.
98.
Paired primary colorectal adenocarcinoma and normal frozen tissue samples from 60 patients were prospectively studied to determine the frequency of point mutations in K-ras and the occurrence of structural alterations in c-myc. Parallel investigations were performed on liver metastatic specimens from 16 of the patients. 47% of the primary tumors presented point mutations in K-ras; 71% of these were in codon 12. Significant associations were found between codon 13 ras mutations and Dukes' D stage (p<0.05), and between mutations in codon 12 and mucinous type (p<0.01). The c-myc gene structure was altered in 5/60 cases (8%). In 4/16 cases, the K-ras gene status in the primary carcinoma and in the metastatic tissue from the same patient was found to be different. Our results suggest that codon 13 I-as mutations may be associated with an increased invasive and metastatic potential, while codon 12 mutations may have a role in the mucinous differentiation pathway.  相似文献   
99.
We describe a simple and fast method for the detection and localization of low copy numbers of HPV DNA in formalin-fixed and paraffin-embedded archival tissues. We have developed a protocol for direct bl situ-PCR in order to demonstrate its convenience in rapid and reproducible assessment of HPV infection in unknown biopsies. The morphological aspect of the tissues has been maintained, despite the multiple steps of fixation, permeabilization and thermal cycling, and positivity has been detected only in virus target cells.  相似文献   
100.
Seven ovarian and one cervical human cancer cell lines were examined far their sensitivity or resistance to tumor necrosis factor, to three topoisomerase II inhibitors and to cisplatin. Only one line exhibited the multidrug-resistance phenotype and another one an 'atypical'-MDR phenotype. The combination of TNF and topoisomerase-II inhibitors produced enhanced cytotoxicity and overcame the MDR and the atypical resistance. No potentiation of cisplatin cytotoxicity was observed. These findings suggest that TNF enhances the activity of DNA topoisomerase II both in TNF resistant and sensitive cells.  相似文献   
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