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1.
We compared the functional status of the hypothalamic dopaminergic tone in patients given an allogeneic hematopoietic stem cell transplantation (allo-HSCT) with chronic graft-versus-host disease (GVHD) with that observed in patients with allo-HSCT without chronic GVHD and in healthy controls. The effect of acute dopaminergic blockade with intravenous metoclopramide on serum prolactin (PRL) concentrations was evaluated. Twenty volunteers, 20 to 52 years of age, seronegative for both hepatitis C virus and the human immunodeficiency virus, were studied: (1) 10 clinically healthy men (group 1), and (2) 9 patients with leukemia, and 1 patient with refractory aplastic anemia who underwent allo-HSCT, 5 of whom (3 men and 2 women) developed chronic GVHD (group 2), and 5 (3 men and 2 women) who did not develop chronic GVHD (group 3). Serum PRL concentrations were measured both fasting and after intravenous administration of metoclopramide (10-mg bolus). The area under the PRL curve was calculated. Patients in group 2 were older than those in groups 1 and 3 (P<.018), but their body mass index was similar. Fasting serum PRL concentrations were similar among the 3 groups; however, group 2 had higher PRL concentrations throughout the test (P<.001) and a greater area under the PRL curve than groups 1 and 3 (P<.001), without differences between the last 2 groups. The differences remained significant after adjustment for age (P<.01). Our results in a small group of patients with chronic GVHD after allo-HSCT suggest the existence of an increased functional level of their hypothalamic dopamine tone, which would favor a tendency toward a diminished endogenous production, release of pituitary PRL, or both. This could represent an adaptive mechanism aiming to maintain circulating PRL concentrations within a physiological range.  相似文献   
2.
Hybrid tumours are very rare salivary gland lesions composed of two or more different tumoural entities in a single neoplasm that arise within a definite topographical region. In most cases adenoid cystic carcinoma has been the predominant component in these lesions. In this study we describe two patients with hybrid tumours located in the palate, one in a 49-year-old woman and one in a 71-year-old man. The first case involved adenoid cystic carcinoma and mucoepidermoid carcinoma, and the patient in the second case exhibited adenoid cystic carcinoma and epithelial-myoepithelial carcinoma. Both patients were treated with surgery and radiotherapy, and there has been no evidence of recurrence after 13 and 36 months of follow-up, respectively. The recognition of the histologic component with the higher grade of malignancy in every case of hybrid tumour of the salivary glands is a necessary step to determine the biological behaviour and, consequently, to determine the proper therapeutic approach.  相似文献   
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Summary The virological findings obtained during an outbreak of Bornholm disease which took place in the summer 1957 in Cermignano, in the province of Teramo, Italy, are described. During this study it was possible to isolate 15 strains of a Goxsackie B2 type virus. 3 strains were isolated simultaneously from rectal and pharyn geal swabs, while 9 strains were isolated from pharyngeal swabs only.  相似文献   
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Lasers in Medical Science - The purpose of this study is to analyze the influence of InGaAlP diode laser (660&nbsp;nm) with or without an odontogenic medium (OM) in the functional activity of...  相似文献   
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Objective: To evaluate the clinical, biochemical, and virologic features associated with hepatitis C virus (HCV) infection acquired early in life from mothers with antibodies to HCV (anti-HCV).Study design: Multicenter prospective-retrospective study in Italian children.Patients: Two groups of children were investigated. Group 1 included 14 infants, born to mothers with anti-HCV but without human immunodeficiency virus infection, who became seropositive for HCV RNA during the first year of life and were thus considered infected. Group 2 included 16 children with chronic hepatitis C, aged 1 ½ to 14 years, whose mothers were the unique potential source of infection. Both groups were followed for 12 to 48 months.Methods: Alanine transaminase (ALT), anti-HCV, and HCV RNA were investigated by the polymerase chain reaction on entry to the study and during follow-up.Results: All children in group 1 had anti-HCV throughout follow-up, and all had ALT abnormalities, ranging from 1.5 to 10.5 times the normal value during the first 12 months. During further follow-up, 5 of 10 children had HCV RNA with abnormal ALT values, 3 had a return to normal of the ALT values but continued to have viremia, and 2 eventually had normal ALT values and clearance of HCV RNA. Of the 16 children in group 2, all were free of symptoms and 62% had only slight ALT elevations; 7 who underwent liver biopsy had histologic features of minimal or moderate hepatitis.Conclusions: HCV infection acquired early in life from mothers with anti-HCV is usually associated with biochemical features of liver damage during the first 12 months of life. Progression to chronicity seems to occur in the majority of cases, although HCV-associated liver disease is likely to be mild throughout infancy and childhood. (J Pediatr 1997;130:990-3)  相似文献   
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Background: Management and preservation of the soft palate is dependent on clinical stage and tumor histology. However, available literature is scarce regarding the palate preservation with the use of laser CO2. Objectives: We report the results obtained after management with laser surgery and soft palate preservation in three patients with salivary gland neoplasms. Method: Three patients with minor salivary gland tumors were treated by means of transoral laser microsurgery. All tumors were assessed using magnetic resonance imaging. All tumors were >3 cm. Soft palate function was preserved and reconstruction was performed with primary closure. Patients began oral feeding the same day and were discharged after 24 h. Conclusions: Transoral laser microsurgery is recommended for treatment of soft palate tumors. This treatment can be considered a better option when compared with other modalities such as radio- or chemoradiotherapy which require a longer time of treatment, are more expensive and tend to produce significant toxicity. Key words:Laser CO2, neoplasms, salivary gland.  相似文献   
9.
Evaluation of cell cycle using antibodies against nuclear proteins involved in regulating DNA replication has gained special interest in the effort to predict biologic behavior of benign and malignant tumors. The aim of this study was to analyze the expression of minichromosome maintenance 2, Ki-67, and geminin in oral nevi and melanomas. Expression of these cell proliferation markers was evaluated by immunohistochemistry in 49 oral melanocytic lesions, including 38 intramucosal nevi and 11 primary oral melanomas. The labeling index of each proliferation marker was assessed considering the percentage of cells expressing nuclear positivity out of the total number of cells, counting 1000 cells per slide. Minichromosome maintenance 2, Ki-67, and geminin were rarely expressed in intramucosal nevi, in contrast to oral melanomas, which showed high levels of these cell proliferation markers, particularly minichromosome maintenance 2, indicating it is a more sensitive marker in primary oral melanomas than Ki-67 and geminin. These results indicate that these markers may be involved in the pathogenesis of oral melanomas and could be eventually useful as an additional diagnostic tool for differential diagnosis of oral benign and malignant melanocytic lesions.  相似文献   
10.
An ultrafast investigation is carried out on synthetic eumelanin suspended either in water or in DMSO-methanol. Upon photoexcitation by visible femtosecond pulses, the transient absorption (TA) dynamics of the suspensions are probed in a broad visible spectral range, showing clear nonlinearities. The latter arise from pump-probe interactions that induce the inverse Raman scattering (IRS) effect. We show how eumelanin TA dynamics are modified in proximity of the solvent Stokes and anti-Stokes scattering peaks, demonstrating that IRS affects the sign of TA but not the relaxation times. We compare the results obtained in both suspensions, unveiling the role of the surrounding environment. Eventually, the intrinsic response of synthetic eumelanin to ultrafast photoexcitation is evaluated.OCIS codes: (160.1435) Biomaterials, (320.7150) Ultrafast spectroscopy, (300.6240) Spectroscopy, coherent transient, (190.5890) Scattering, stimulated  相似文献   
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