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Administration of supraphysiological doses of testosterone to normal men causes inhibition of spermatogenesis, but while most become azoospermic, 30-55% maintain a low rate of spermatogenesis. We have investigated whether there are differences in endogenous androgen production, of testicular and adrenal origin, which may be related to the degree of suppression of spermatogenesis. Thirty-three healthy Caucasian men were given weekly i.m. injections of 200 mg testosterone oenanthate (TE), 18 became azoospermic, while 15 remained oligozoospermic. Urinary excretion of epitestosterone, a specific testicular product, was reduced to <10% of pretreatment values, with no differences between the groups. Similar results were obtained for other markers of testicular steroidogenesis. Urinary and plasma adrenal androgens were also reduced during TE treatment: a statistically significant decrease in both (P < 0.001 and P < 0.05 respectively) was seen in the azoospermic but not oligozoospermic responders. These results suggest that testicular steroidogenesis is decreased to <10% by the administration of supraphysiological doses of exogenous testosterone. Differences in the degree of ongoing steroidogenesis in the testis do not appear to account for incomplete suppression of spermatogenesis, thus differences in androgen metabolism may underlie this heterogeneous response. A small but significant reduction in secretion of adrenal androgens was also detectable, the relevance of which is unclear.   相似文献   
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Monette  FC; Holden  SA 《Blood》1982,60(2):527-530
Since exogenous hemin has been shown to exert a variety of stimulatory effects on erythroid cells, including the augmentation of hemoglobin synthesis, we determined its effect on early stages of erythroid development by employing clonal cells assays. The addition of hemin at a concentration of 2 X 10(-4) M to cultures of normal murine marrow substantially increased the observed number of primitive BFU-E, which was in contrast to its lack of an effect on more mature erythroid colony-forming cells. This cell-specific enhancement of primitive BFU-E resulted in marrow frequencies equivalent to or exceeding those reported in the presence of "burst-promoting activity." In the presence of hemin, the number of BFU-E was also observed to be linearly related to the number of cells plated at very low plating densities, and the cell titration curve was observed to extrapolate to the origin. The evidence suggests that hemin may be a primary growth regulator of early developmental stages of erythroid progenitor cells.  相似文献   
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Objectives: The aim of the present study was to evaluate the effect of Erythrina mulungu on the control of dental anxiety in patients who had under gone bilateral extraction of asymptomatic, impacted mandibular third molars. Material and Methods: In a randomized, double-blind, crossover study, 30 healthy volunteers (5 men and 25 women, over 18 years of age), received either 500mg of E.mulungu (Mulungu Matusa®) or 500 mg of placebo, p.o., one hour before surgical procedure. The level ofanxiety was assessed through questionnaire sand physical parameters, such as blood pressure, heart rate andoxygen saturation. Data were analyzed by Chi-square test, ANOVA (Tukey test) and Friedman with significance level of 5%. Results: A higher preference (Chi-square, p = 0.0062) for E. mulungu was observed for both genders. Volunteers with higher anxiety levels tended to to prefer E. mulungu. No statistically significant differences were verified in blood pressure (one-way ANOVA, p = 0.1259), heart rate (Friedman, p> 0.05) and oxygen saturation (Friedman, p = 0.7664) among periods and types of treatments. Conclusions: E. mulungu showed an anxiolytic effect without significant changes in physiological parameters. It could be considered as an alternative to control the anxiety in adult patients undergoing mandibular thirdmolars surgery. Key words:Anxiety, Erythrina mulungu, third molar, oral surgery.  相似文献   
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We have used cone-beam computed tomographic (CT) images to retrospectivelyevaluate the influence of sex, skeletal class, facial type, and the presence of septa on the volume of the sphenoid sinus in 172 images from 85 men (mean (SD) age 28 (2) years) and 87 women (mean (SD) age 30 (1) years). Skeletal class and facial type were calculated for each patient from multiplanar reconstructions using NemoCeph® software. Volumetric analysis of the sphenoid sinus was made with the help of the ITK-SNAP® 3.4.0 segmentation software, while the presence or absence of septa in the sphenoid sinus was evaluated with the Carestream 3D Imaging® software 3.4.3. We analysed the results using two-way ANOVA, Student’s independent sample t test, and Fisher’s exact test, as appropriate, and probabilities of <0.05 were accepted as significant. Sex (p = 0.0946), facial type (p = 0.790), and skeletal class (p = 0.120) had no significant influence on the volume of the sphenoid sinus, and nor did the volumes of the right and left sphenoid sinuses (p = 0.0923), or the presence of a septum within the sinus (p = 0.330) in its volume.  相似文献   
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Journal of NeuroVirology - We describe two neurological cases of Oropouche virus infection in northern Brazil, where the virus is endemic but neglected as a pathogen. This study reiterates the...  相似文献   
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Objectives:To present the ballistic gelatin as a new material capable of simulating the soft tissues in cone-beam CT (CBCT) images.Methods:CBCT images of three piglet heads were acquired with their soft tissues intact (standard group). Subsequently, the piglet heads were fixed in a container using metallic pins and moulded with acrylic resin; the soft tissues were then removed and replaced by ballistic gelatin, with the same thickness of the original soft tissues. The images were evaluated by two oral radiologists, to check the adaptation on bone surfaces, thickness and density, penetration into large bone cavities and cancellous bone, and the presence of air bubbles using a 5-score scale. Additionally, an objective analysis was carried out by one oral radiologist. For each CBCT scan, three axial reconstructions were selected to represent the mandibular, occlusal, and maxillary levels. The mean and standard deviation (SD) of the grey values were calculated in four regions of interest determined on soft tissue areas and compared by two-way ANOVA.Results:The ballistic gelatin showed subjective scores ranging from good to excellent for all parameters evaluated. There was no significant difference in the mean and SD values of the grey values between ballistic gelatin and the gold standard groups for all levels (p > 0.05). Higher SD values were observed in the occlusal level for both groups (p < 0.05).Conclusions:Ballistic gelatin has visual and objective similarity with the gold standard. Thus, the ballistic gelatin is a promising material capable of simulating soft tissues in CBCT images.  相似文献   
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