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81.
Neurosurgical Review - Chordoma is a rare slow-growing neoplastic bone lesion. However, they show an invasive local growth and high recurrence rate, leading to an overall survival rate of 65% at 5...  相似文献   
82.
Annals of Surgical Oncology - Long-term pancreatoduodenectomy (PD) survivors have previously reported favorable quality of life (QoL). However, there has been a paucity of studies utilizing...  相似文献   
83.
The role of tumour suppressor genes in the development of human cancers has been studied extensively. In viral carcinogenesis, the inactivation of suppressor proteins such as retinoblastoma (pRb) and p53, and cellular oncogenes overexpression, such as c-myc, has been the subject of a number of investigations. In uterine-cervix carcinomas, where high-risk human papillomavirus (HPV) plays an important role, pRb and p53 are inactivated by E7 and E6 viral oncoproteins, respectively. However, little is known about the in situ expression of some of these proteins in pre-malignant and malignant cervical tissues. On the other hand, it has also been demonstrated that c-myc is involved in cervical carcinogenesis, and that pRb participates in the control of c-myc gene expression. By using immunostaining techniques, we investigated pRb immunodetection pattern in normal tissues, squamous intraepithelial lesions (SILs) and invasive carcinomas from the uterine cervix. Our data show low pRb detection in both normal cervical tissue and invasive lesions, but a higher expression in SILs. C-Myc protein was observed in most of the cellular nuclei of the invasive lesions, while in SILs was low. These findings indicate a heterogeneous pRb immunostaining during the different stages of cervical carcinogenesis, and suggest that this staining pattern could be a common feature implicated in the pathogenesis of uterine-cervix carcinoma.  相似文献   
84.
Receptors for IgM were detected on peripheral blood human eosinophils by a rosette technique with ox red blood cells coated with the IgM fraction of the specific immunserum. Between 14 % and 43 % (mean 27 %) FcµR positive cells were found after an overnight incubation period at 37°C by using this technique. The specificity of the receptors for IgM was assessed by studying the inhibitory capacity of purified human IgM in the rosette assay. From an ultrastructural point of view, the EAM rosette-forming cells are mature eosinophlic granulocytes characterized by a nucleus with a variable number of lobes and a certain number of «first type» granules partially or totally devoid of their content.  相似文献   
85.
In 73 pregnant patients at a gestational age under 36 weeks, who gave birth within 72 hours from the last US examination, mathematical equations were elaborated. The equations were aimed at predicting fetal weight by measuring the main US biometric parameters; the results were compared to the actual birth weight. A statistical analysis was performed using the "backward elimination" method. The linear equation that has provided with the best estimation of fetal weight is the following: fetal weight = 12.9875 BPD +29.5642 AD +28.8023 FL -3496.1265. According to this equation, about 95.22% of the variability of the unknown quantity (i.e. birth weight) can be ascribed to its correlation to the variables: biparietal diameter (BPD), abdominal diameter (AD) and femur length (FL). Estimated fetal weight by US, as calculated on the basis of biparietal diameter, abdominal diameter and femur length measurements, showed, in our study, a standard error of 143 g (9.02%) (R = 0.95).  相似文献   
86.
87.
Multiple sclerosis (MS) is a T-cell-mediated autoimmune demyelinating disease of the central nervous system (CNS), associated with an altered immunoregulation. Interferon (IFN)-, also known as immune IFN, is a cytokine with several effects on the immune system. Specific IFN- receptors have been found on human lymphocytes, as well as on other cell types (e.g. gliocytes), even in the CNS. The aim of the present study was to evaluate IFN- binding on peripheral blood T-lymphocytes from MS patients, compared with those from healthy subjects. Thirty-two patients were selected according to the classical criteria for definite MS; as controls, 21 healthy subjects were studied. We have found that T-lymphocytes from MS patients bear a significantly smaller amount of IFN- receptors than those from controls [B max: 568, 18 vs 708, 14 (mean, SE) receptors/cell]. Such IFN- binding sites are of the same type in patients and healthy subjects [K d: 1.0, 0.05 vs 0.9, 0.02 (mean, SE) nM]. These findings are discussed in terms of immunopathogenesis of MS, since it has been reported that activated T-lymphocytes have decreased amounts of IFN- receptors.  相似文献   
88.
Summary The influence of respiratory and metabolic acid-base alterations on the myocardial sensitivity to catecholamines was studied in the isolated rat atria. The ability of noradrenaline for increasing the atrial rate was enhanced during alkalosis and conversely, it was decreased by acidosis. These changes in sensitivity shifted the concentration-effect curve for noradrenaline to the right by about 0.5 log unit when the pH was lowered from 7.60 to 7.00. No changes in the maximum attainable response were detected. Essentially the same shifts of the concentration-effect curves were obtained with changes in pH brought about by altering the pCO2 or at constant pCO2. The decrease in the pH produced a similar shift to the right of the concentration-effect curve for isoprenaline, after the extraneuronal uptake inhibition by hydrocortisone and also in atria tissue with low content of endogenous noradrenaline (reserpine-pretreated and newborn rats). The ability of isoprenaline for increasing cyclic AMP levels in atrial tissue was also enhanced by alkalosis and decreased by acidosis. However, the shift to the right of the concentration-effect curve for cyclic AMP induced by the decrease in the pH was greater than the shift detected in the chronotropic-effect curve. In addition a decrease in the maximum increment of cyclic AMP was detected under acidosis, in spite of equal maximal chronotropic response.Our results support the hypothesis that the alterations in the sensitivity to catecholamines induced by the changes in pH are not due to a release of endogenous noradrenaline nor to alterations of the mechanisms which remove catecholamines from the biophase. The fact that cyclic AMP response to catecholamines was also reduced by acidosis strongly suggests that the mechanism(s) involved is located in the earlier steps of the events leading to the chronotropic effect of the -agonists.  相似文献   
89.
A perspective study was carried out at the Emergency Department of the Gaslini Institute on a sample of the children admitted from May to September 1990. The study aimed to describe types and modalities of admission. "G. Gaslini" Institute is a multidisciplinary children's hospital: 45% of patients admitted in the hospital come from the southern regions of Italy, while the admission at the Emergency Department were local in 82%. Among all children considered, 2080 (71.9% were admitted on request of their parents, who did not ask previously any physician; of those cases, 356 (17%) were hospitalized, 474 (25%) were either examined by specialist or treated and then discharged. In the remaining cases, no intervention was necessary. As a consequence, 58% of children were admitted without any clinically plausible reason. Parents' anxiety clearly played an important role in most cases. 840 children were addressed to the Emergency Department by a physician, 652 (22.3%) by the doctor in charge, 213 (32.7%) of which were sent back home by the doctor on duty, who did not think it necessary any treatment. Of the 120 (4.1%) children sent by different Emergency Departments, 95 (79.1%) were hospitalized. The reason why physicians addressed quite a large number of children to the Emergency Department, when they didn't need any intervention remain nucleo. Their diagnosis, in fact, agreed with those of the doctor on duty in 83% of cases. In conclusion, it is difficult to imagine a diagnostic or therapeutic problem which needs specific structures. Cooperative programs with physicians working in our region will be carried out in order to control, where possible, admission to Emergency Departments.  相似文献   
90.
The authors reviewed records of admission at the Fist Ais-Emergency Service of "G. Gaslini" Children's Hospital, data referring both to in and outpatients. First of all we took into account epidemiological data analysing occurrence and types of diseases; at the same time a demographic study, which aimed to show a decrease in the child population in Genova, was performed. Secondly we compared these data with the real number of admitted patients: collected data showed that this service has been used excessively.  相似文献   
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