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51.
Rosai Dorfman Disease (Sinus Histiocytosis with massive lymphadenopathy) is a rare self-limiting histiocytic disorder of unknown etiology usually presenting with cervical lymphadenopathy and haematological abnormalities. Extra-nodal presentation is rare . This ease is such a rare presentation of Rosai Dorfman Disease.  相似文献   
52.
Central noradrenergic mechanisms may participate in the regulation of pulsatile gonadotropin secretion in women with the polycystic ovary syndrome (PCO). To examine this possibility we measured serum LH, FSH, and PRL concentrations at 10-min intervals and total testosterone and 17 beta-estradiol at 60-min intervals for 8 h basally and during the infusion of the alpha 1-adrenoceptor antagonist thymoxamine (10 micrograms/kg X min) in 10 young women with PCO. Mean and integrated serum LH concentrations as well as LH pulse frequency were not significantly altered (P = NS) during the thymoxamine infusion. However, we found an increase in LH pulse amplitude as both net (P less than 0.002) and percent (P less than 0.002) increment, as well as mean LH peak values (P less than 0.05) during alpha 1-adrenergic blockade. There were no significant changes in pulsatile FSH and PRL secretion or gonadal sex steroids during these experimental conditions. These data suggest that in PCO patients, 1) brain noradrenergic mechanisms do not play a stimulatory role in regulating the frequency of pulsatile LH secretion, 2) central noradrenergic activity inhibits LH pulse amplitude, and 3) PRL and FSH pulsatility are not altered by central noradrenergic blockade.  相似文献   
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Ketoconazole therapy for women with acne and/or hirsutism   总被引:3,自引:0,他引:3  
The effects of ketoconazole, a synthetic imidazole derivate, were evaluated in 42 women affected by acne (17 cases) and/or hirsutism (36 cases) treated with 400 mg/day for 3-6 months. Androstenedione, total and free testosterone, 5 alpha dihydrotestosterone and dehydroepiandrosterone levels progressively dropped during treatment while 17 alpha hydroxyprogesterone, estradiol, ACTH, cortisol, LH and FSH levels increased. Dehydroepiandrosterone sulfate decreased only towards the end of treatment, while estrone, sex hormone binding globulin, and PRL remained unchanged. Daily mean +/- SD rate of hair growth, measured by a special image analysis processor, decreased within 3 months of therapy from 0.258 +/- 0.058 to 0.184 +/- 0.039 mm/day (P less than 0.02) and mean +/- SD hair diameter from 0.123 +/- 0.015 to 0.110 +/- 0.013 mm (P less than 0.05) together with decreasing hormone levels. The therapeutic effects of ketoconazole on hirsutism was evident at 6 months in only 14 subjects, while no significant change in hirsutism score was recorded in 22 women who failed to complete the therapy. Acne improved in all cases. Several side effects and complications arose during treatment, such as headache, nausea, loss of scalp hair, hepatitis, and biochemical changes. Even though ketoconazole improves hyperandrogenism, only selected patients are eligible for treatment as scrupulous monitoring is required.  相似文献   
55.
Oxidative degradation of artificial UHMWPE joint implants caused by gamma-ray sterilization is thought to be responsible for the production of wear debris resulting in adverse tissue responses. On the other hand, it is well known that inflammation is associated with generation, by inflammatory cells, of free radicals (H(2)O(2) and NO) and destructive proteolytic enzymes (collagenases), which creates a strong oxidative environment. We hypothesized that when an UHMWPE implantation was performed in an inflammatory joint environment, the oxidative substances produced by inflamed synoviocytes could increase oxidative degradation of the polyethylene insert. We measured the amount of free radicals on conventional and on Duration-treated polyethylene samples by the electron spin resonance (ESR) technique before and after exposure of the samples to (1) inflamed synovial cell cultures; (2) normal synovial cell cultures; and (3) medium alone. We observed an increase in the number of free radicals on polyethylene samples after their immersion in cell cultures. Furthermore, it was observed that the increase of free radicals on polyethylene correlated with the degree of inflammation of synovial cells in culture.  相似文献   
56.
The hypothesis that a neural depressive action is related to the antihypertensive effects of beta blockers has been evaluated in 14 essential hypertensive male patients through the circulatory response to noxious stimuli. The pressor reaction to mental arithmetic was primarily mediated by cardiac stimulation (beta receptors activation), that to cold by vasoconstriction (alpha receptors activation). Arithmetic and cold were tested to separate the effects of peripheral beta blackade from possible neural and other influences. After propanolol (320 mg per day for 3 wk): (1) The baseline pressure was reduced; (2) appearance, peak, and disappearance time of the circulatory reaction to either stimulus was not altered; (3) the pressor effect of arithmetic was decreased in an extent proportional to the reduced rise of cardiac output; and (4) pressure during cold reached the pretreatment levels through an augmented increase of vascular resistance. Our findings indicate that propranolol depresses only the circulatory reactions mediated through beta receptors activation and provide no evidence of effects other than beta blockade.  相似文献   
57.
Cytomegalovirus (CMV), Epstein-Barr virus (EBV), and adenovirus (Ad) cause significant morbidity and mortality in immunocompromised patients undergoing allogeneic stem cell transplantation. We have established a procedure to generate polyclonal cytotoxic T lymphocyte (CTL) populations with specificity against Ad and CMV or against Ad and EBV. Healthy donor-derived dendritic cells (DCs) were transduced with recombinant adenovirus encoding either CMV pp65 or EBV EBNA3C and used to stimulate autologous T cells. Stimulated T lymphocytes displayed specific simultaneous cytotoxicity against CMV and adenovirus and to a lesser extent against adenovirus and EBV. Recombinant vaccinia virus encoding individual adenovirus proteins showed that the T cell response to the adenovirus was directed mainly against the capsid protein hexon. The frequency of IFN-gamma-secreting T cells was 0.02% for adenovirus alone, and 0.05 and 0.14% for adenoviruses encoding EBNA3C and pp65, respectively. pp65-specific CTLs killed autologous fibroblasts infected with the laboratory strain CMV AD169. The culture conditions were specific as alloreactive T cells were not expanded. Therefore, this approach could be considered in order to generate efficient virus cytolytic T cells to be used as adoptive immunotherapy in transplanted patients.  相似文献   
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59.
Unilateral cochlear implant (CI) stimulation establishes hearing to children who are deaf but compromises bilateral auditory development if a second implant is not provided within ~1.5 years. In this study we asked: 1) What are the cortical consequences of missing this early sensitive period once children reach adolescence? 2) What are the effects of unilateral deprivation on the pathways from the opposite ear? Cortical responses were recorded from 64‐cephalic electrodes within the first week of bilateral CI activation in 34 adolescents who had over 10 years of unilateral right CI experience and in 16 normal hearing peers. Cortical activation underlying the evoked peaks was localized to areas of the brain using beamformer imaging. The first CI evoked activity which was more strongly lateralized to the contralateral left hemisphere than normal, with abnormal recruitment of the left prefrontal cortex (involved in cognition/attention), left temporo‐parietal‐occipital junction (multi‐modal integration), and right precuneus (visual processing) region. CI stimulation in the opposite deprived ear evoked atypical cortical responses with abnormally large and widespread dipole activity across the cortex. Thus, using a unilateral CI to hear beyond the period of cortical maturation causes lasting asymmetries in the auditory system, requires recruitment of additional cortical areas to support hearing, and does little to protect the unstimulated pathways from effects of auditory deprivation. The persistence of this reorganization into maturity could signal a closing of a sensitive period for promoting auditory development on the deprived side. Hum Brain Mapp 37:135–152, 2016. © 2015 Wiley Periodicals, Inc.  相似文献   
60.
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