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Several experiences induced us to consider genital HPV infection as an expression of a local immunodeficiency. The aim of our study was to research the effect of immunotherapy on the lymphocyte subpopulations and Langerhans cells in vulvar condyloma. Twenty women with persistent vulvar condylomata, treated with 2,000,000 IU/die of beta-interferon for 15 days, were submitted to vulvar biopsy before and 2-5 months after medical treatment. The frozen sections obtained were assayed with the following monoclonal antibodies: OKT 4 (T helper lymphocytes), OKT 8 (T suppressor lymphocytes), OKB 7 (B lymphocytes) and S-100 protein (Langerhans cells). Using a morphometric evaluation, the average number of both intraepithelial and stromal lymphocyte subsets and of the intraepithelial Langerhans cells was assessed. In all the biopsies preceeding the medical treatment we found a low number of T helper lymphocytes both in the epithelium and stroma, with inversion of T4/T8 lymphocyte ratio and rare presence of Langerhans cells. In patients with a good therapeutic response (50-100% of condyloma reduction) we observed an increase in intraepithelial T4 lymphocytes and a decrease in both intraepithelial and stromal T8 lymphocytes. In cases with persistent disease after therapy, the histological pattern was similar to that observed in the first biopsy, with the exception of a significant increase in the average number of Langerhans cells. Our data correlate the clinical response to the immunotherapy with the histology of lymphocyte subsets in the vulvar condylomata. The increase in Langerhans cells observed in patients with negative response may be interpreted with a probable inability of these cells to promote the immune reaction.  相似文献   
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Monte Carlo simulations were carried out to simulate the response of a boron-loaded plastic scintillator array. These detectors offer potential advantages compared to moderated 3He systems because of their fast response and high efficiency. Tallies were made of neutron capture probability as a function of time and the results were coupled to assay variance estimates to evaluate detector performance. Orders-of-magnitude reductions in count time relative to a 50% efficient thermal counter are possible, in principle, for high (α,n) samples.  相似文献   
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D Russo  A Testa  L Della Volpe  G Sansone 《Nephron》1990,55(3):254-257
Contrast media affect renal hemodynamics. Hyperosmolality is regarded as the major factor responsible for renal hemodynamic changes. In this study, the role of osmolality was evaluated in 30 hospitalized patients without risk factors during intravenous pyelography. Contrast media with low and high osmolality were used. In addition, nifedipine was administered before infusion of high-osmolality contrast to evaluate the role of calcium ions in radiocontrast-induced changes of renal hemodynamics. Hyperosmolar contrast reduced renal plasma flow and glomerular filtration rate. Calcium channel blocker prevented changes of renal hemodynamics. Hyperosmolality appears the most likely factor affecting renal hemodynamics during hyperosmolar radiocontrast infusion. Calcium channel blocker may prevent renal changes due to hyperosmolar medium.  相似文献   
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Sixty-seven insulinomas were investigated by immunohistochemistry using site-directed antibodies against insulin, proinsulin, chromogranin A, HISL-19, and four proteins directly or indirectly involved in the proteolytic processing of proinsulin: the prohormone convertases PC2 and PC3, carboxypeptidase H (CPH) and 7B2. Results were expressed in a six-grade score according to the frequency of immunoreactive tumour cells. Insulin was expressed by all tumours, appearing in either a diffuse or a polarized pattern and being detected in more than 30% of tumour cells in all cases but three. Proinsulin was also expressed in all tumours, with more than 50% of tumour cells immunoreactive in all cases but 5. It was consistently localized in the Golgi apparatus. In about half the cases, moreover, it also showed diffuse cytoplasmic staining, usually with a very sparse distribution. Trabecular and solid insulinomas did not present specific, homogeneous patterns of insulin immunostaining. However, insulin immunoreactivity was much more abundant in trabecular than in solid neoplasms, being present in virtually all tumour cells (score 6) in 50% and 8% of cases, respectively. Virtually all insulinomas expressed PC2, PC3, CPH and 7B2, usually in 30–100% of tumour cells, with a frequency significantly related to that of insulin. However, detection of PC2 and 7B2 was slightly less frequent than that of PC3 and CPH. In consecutive sections these proteins were found to be mostly co-localized with insulin and chromogranin A but not with proinsulin. They were heavily expressed in all 10 tumours with more than 10% of cells showing cytoplasmic proinsulin immunoreactivity, indicating that the leakage of proinsulin from the Golgi compartment is not associated with faulty expression of converting enzymes and possibly reflects a saturated processing capacity. HISL-19 immunoreactivity was found in both Golgi apparatus and insulin stores, indicating that the relevant antigen is different from all other proteins investigated. These results do not support a defect in expression or localization of proinsulin-processing enzymes in most insulinomas.  相似文献   
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10 patients operated on for anterior communicating artery aneurysm (ACoA) underwent to neuropsychological examination one year after surgery, in order to detect eventual behavioural and/or amnestic disorders, already described by others in a wide percentage of such patients. Even if after accurate neurological examination the therapeutic results were defined as "good", 60% circa of our patients present amnestic and/or behavioural disturbances. Possible correlations between neuropsychological tests finding and intraoperative occurrences (early aneurysm rupture, gyrectomy etc.) are considered and discussed.  相似文献   
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A series of 21 neuroleptics with different chemical structures (phenothiazines, thioxanthenes, dibenzodiazepines, butyrophenones, benzamides, etc.) was examined for their in vitro interactions with 12 neurotransmitter binding sites in the rat brain (alpha- and beta-noradrenergic, dopaminergic, muscarinic, serotoninergic, histaminic, and opioid receptors, calcium channels, and serotonin uptake binding sites). The biochemical profile obtained from the binding data was compared with reported pharmacological and clinical profiles for this class of compounds by cluster analysis. Cluster analysis on binding data classified the compounds in three main subgroups: benzamides, compounds with an affinity mainly for DA2 and 5-HT2 receptors and inactive at muscarinic receptors, and compounds with a high affinity for alpha 1-adrenergic receptors and muscarinic receptors. The main subgroups resulting from cluster analysis of previously published pharmacological and clinical data for neuroleptics contain compounds common to the present study, with some correlations. The results extend previous observations that a complete binding profile corresponds to the pharmacological and clinical profile of this class of compounds.  相似文献   
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Summary The protein populations of epithelial cells cultured from two neoplastic and five non-neoplastic human breast tissues were resolved and displayed by two-dimensional polyacrylamide gel electrophoresis and silverstaining. With a computer-based image analysis system, we identified eight polypeptides which are present in both of the neoplastic cell lines, but absent from all five of the cultures of non-neoplastic breast cells. The eight polypeptides are not unique to cells cultured from neoplastic breast, because they are also found in cells cultured from non-breast tissues, both neoplastic and non-neoplastic. Two of the eight polypeptides ( Mr 25,000/pI 4.4 and Mr 31,000/pI 5.5) are present in the patterns of whole tissue samples from infiltrating ductal carcinomas and absent in most normal breast tissue.  相似文献   
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