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Immunohistochemistry profiles of medulloepithelioma (from two 2 1-year-old girls who had 2 cerebral medulloepitheliomas and a 35-week postconceptional female infant with congenital posterior fossa tumor) and neural tube are compared. Microscopically, the tumors contained a medulloepitheliomatous component, manifested as tubular epithelial structures lined by pseudostratified columnar epithelium delineated by well-defined basement membranes. In all cases, glial and neuronal differentiation were noted to differing extents. The medulloepitheliomatous components did not exhibit glial fibrillary acidic protein, neuron-specific enolase, or S-100 protein reactivity. Neurofilament, cytokeratin, and epithelial membrane antigen were focally present in one case. Extensive nestin immunopositivity was confined to the basal cell layer of the epithelium, leaving the luminal surface unreactive or slightly reactive. These cells also displayed a reactivity to vimentin and to microtubuleassociated protein type 5 similar to that of cells of the primitive neural tube. The similarity between the immunohistochemical profile of medulloepithelioma and that of neural tube epithelium suggests a possible reexpression of that component of the genome responsible for neural tube growth and differentiation in medulloepithelioma.  相似文献   
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Clinical Rheumatology - The clinical benefits of rituximab in systemic sclerosis (SSc) are still contentious. The present meta-analysis aimed to systematically assess rituximab’s safety and...  相似文献   
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BackgroundComplementary and alternative medicines have been used to increase comfort and relaxation in mothers during labor. Comforting and preparing the mother in labor can create a positive birth experience. The aim of this study was to evaluate the effect of acupressure on childbirth satisfaction and the experience of giving birth in women with full-term pregnancy, before the onset of labor.MethodsIn 2016, a randomized clinical trial study was conducted in Shahid Akbar Abadi Hospital, Tehran, Iran, enrolling 120 pregnant women at 39–40 gestational weeks with no signs of the onset of labor. They were divided randomly into acupressure, sham acupressure, and control groups. Acupressure points including SP6, BL 60, and BL 32 were pressured bilaterally. Interventions were performed by the researcher, the mother and her relative (husband). Childbirth satisfaction was measured 24 h after delivery. The collected data were analyzed by SPSS software and comparing tests were Chi-squared, Kruskal-Wallis, ANOVA tests (P ≤ 0.05).ResultsThe total childbirth satisfaction did not differ significantly among the three groups (P = 0.460), but the acupressure group had a higher level of satisfaction than the other two groups. Moreover, statistical tests regarding the expectations of the childbirth experience showed a significant difference among the groups (P = 0.033). The actual birth was closest to the expectations of subjects in the acupressure group.ConclusionThis study demonstrated that acupressure may be used as a method in order to attempt to provide a good birth experience and satisfaction of childbirth.  相似文献   
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Chronic lead exposure during development is known to produce learning deficits. In the present study, we investigated the effects of developmental exposure to lead on spatial memory, as shown in the Morris water maze, and on expression of inducible cyclooxygenase-2 protein in the hippocampi of male rats. Rats were separated into four groups according to which concentration of lead acetate at which developmental stage they were exposed. One group was exposed maternally to lead acetate at a concentration of 250 parts per million (ppm), one group was exposed continuously to 250 ppm lead, one group was exposed maternally to 750 ppm lead, and one group was exposed continuously to 750 ppm lead. Increases were observed in both average escape latency and traveled distance of the rats in the maternally and continuously 750 ppm lead-exposed groups, indicating significant impairment of spatial memory. Quantitative immunostaining analysis by optical density measurement of brain sections from rats in all lead-exposed groups revealed a significant reduction (P < 0.001) in the intensity of cyclooxygenase-2 immunoreactivity in the Ammon's horn region 1 (CA1) and the dentate gyrus areas of the hippocampus. This reduction was concentration-dependent, with the maximum reduction observed in rats exposed to 750 ppm lead. Taken together, these findings suggest that exposure to lead causes spatial memory deficits in male rats and a significant reduction in cyclooxygenase-2 immunoreactivity in the CA1 and dentate gyrus areas.  相似文献   
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OBJECTIVES: To evaluate the feasibility of radical retropubic prostatectomy (RRP) as an option for treating men older than 70 years with organ confined prostate cancer and to compare biochemical progression-free survival with younger cohorts. MATERIALS AND METHODS: A total of 689 consecutive patients who were treated with RRP from 1994 to 2002 for clinically localized prostate cancer were categorized into 3 different age groups: younger than 50 years (n = 49), 50-70 years (n = 601), and older than 70 years (n = 39). Patients older than 70 years were healthy individuals for their age. Preoperative and postoperative cancer-specific characteristics were compared among these 3 groups. RESULTS: There was no statistical significant difference among the 3 age strata in terms of clinical parameters (prostate-specific antigen, Gleason score, clinical stage, percent and number of positive biopsy cores) and pathologic findings (surgical margin, lymph node status, extracapsular extension, lymphovascular invasion, and pathologic Gleason score). The rate of seminal vesicle invasion and prostate volume increased with advancing age (P = 0.034 and P < 0.001). In multivariate logistic regression analysis, age was not associated with seminal vesicle invasion. The 5-year prostate-specific antigen progression-free estimates for patients younger than 50, 50-70, and older than 70 years were 82% (95% confidence interval [CI] 69% to 96%), 82% (95% CI 78% to 86%), and 65% (95% CI 43% to 86%), respectively (P = 0.349). The overall and cause-specific mortalities were not different. CONCLUSIONS: RRP could be considered a standard treatment option in men older than 70 years with localized prostate cancer. Further studies are necessary to assess the survival benefit and health-related quality of life after radical prostatectomy versus watchful waiting in patients older than 70 years.  相似文献   
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OBJECTIVE: To verify the effect of chronic lithium administration on the endothelium-dependent relaxation of rat corpus cavernosum, as lithium is a major drug for treating bipolar disorder and some studies showed that lithium might cause erectile dysfunction in such patients, by a mechanism as yet unknown. MATERIALS AND METHODS: LiCl (600 mg/L) was dissolved in drinking water and Sprague-Dawley rats received the solution for 30 days; control rats received tap water. After 30 days corporeal strips were prepared from both groups, mounted under tension in oxygenated organ baths, and pre-contracted with phenylephrine (7.5 microm). After equilibration, the strips were relaxed by acetylcholine (10 nm to 1 mm) in the presence or absence of indomethacin (a cyclooxygenase inhibitor; 20 microm). Furthermore, the relaxant responses to sodium nitroprusside (1 nm to 1 mm), a nitric oxide (NO) donor, were investigated in both groups. NADPH-diaphorase histochemistry was used to identify NO synthase within cavernosal tissue strips of both groups. RESULTS: The acetylcholine-dependent relaxation was significantly lower in lithium-treated rats than in controls. Although indomethacin decreased significantly the relaxant responses to acetylcholine in controls, it increased the relaxant responses in lithium-treated rats. NADPH-diaphorase staining was greater in the chronic lithium-treated than in control preparations. Sodium nitroprusside produced similar relaxation in both groups. CONCLUSION: Chronic lithium administration can impair the endothelium-dependent relaxation of rat corpus cavernosum; NO availability might decrease after lithium administration and the cyclooxygenase pathways might have a role in this effect.  相似文献   
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Disorders of sex development (DSD) are congenital conditions in which the typical genetic and hormonal profiles are affected and thereby the usual process of sexual differentiation. Most of these studies, however, have been conducted in Western countries. In the present study, preschool sex-typed activities of Iranian individuals with DSD and their age-matched non-affected male and female relatives were assessed using the Pre-School Activities Inventory (PSAI) modified for retrospective self-report. A total of 192 individuals participated in our study, including 33 46,XX individuals with congenital adrenal hyperplasia (CAH; M age?=?10.36, SD?=?5.52), 15 46,XY individuals with complete androgen insensitivity syndrome (CAIS; M age?=?19.8, SD?=?7.14), and 16 46,XY individuals with 5-alpha reductase deficiency type-2 (5α-RD-2; M age?=?17.31, SD?=?7.28), as well as one age-matched non-affected male and female relative for each patient. With regard to PSAI scores, male-identifying participants with 5α-RD-2 and male controls reported similar levels of male-typical childhood play. Female-identifying participants with 5α-RD-2 and CAH showed comparable scores: significantly less masculine and more feminine than male controls, but significantly more masculine and less feminine than females with CAIS and female controls. These findings support the role of androgens in the development of sex-typical childhood play behavior, with those being exposed to higher levels of fetal functional androgens expressing more masculine behavior at preschool ages.  相似文献   
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Introduction: The highest mortality from scorpion stings in Iran is due to the stings of a particular type of scorpion known as Hemiscorpius lepturus (H. lepturus, Gadim in local language). The present study aimed at investigating the use of plasmapheresis to treat severe cases of H. lepturus stings.

Method: This pilot study was a randomized clinical trial conducted from June 2015 to June 2016 in Razi hospital of Ahvaz, Iran. Twenty-nine patients who had been stung by H. lepturus and admitted to ICU because of disseminated intravascular coagulation (DIC) were randomly assigned into control (15 patients, supportive treatments) and plasmapheresis (14 patients, supportive treatments?+?plasmapheresis) groups, and the patient outcomes were compared between the two groups.

Findings: Eighteen patients were female (62%), and the mean of patient age was 24?±?7. Most of the sting cases had occurred in the torso (15 patients, 52%). Only 10 patients (34%) arrived in the hospital within 12?h of being stung. There was no significant difference between the two groups in terms of the demographic and sting features. In the plasmapheresis group, hemoglobin level was significantly lower, while the PT and INR were measurably higher. In total, the plasmapheresis group experienced 29 sessions of treatment (an average of two sessions for each patient). Overall, 19 patients (66%) expired, whereas 10 patients (34%) experienced recovery with or without complications. The rate of recovery was significantly higher in the plasmapheresis group compared with controls, with eight patients (57%) in the plasmapheresis group surviving compared with two (14%) in the control group (p=.045). The duration of hospitalization was higher in the plasmaphersis group (p?Conclusions: The findings of this small-scale pilot study show that using plasmapheresis in treating DIC in patients stung by H. lepturus can prevent death and encourage recovery. However, prior to using plasmapheresis as a routine treatment for severe cases of people stung by this scorpion or other similar ones, further controlled studies with a larger sample size are needed.  相似文献   
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