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1.
Induction of oxidative stress during the sperm preparation process for assisted reproductive techniques (ART) in men can weaken sperm parameters. Vitamin E (VE) is considered a factor in boosting male fertility. This experimental study (in vitro) aimed to assess the impact of VE supplementation on sperm quality and lipid peroxidation during sperm sampling at different times. For this mention, semen samples were collected from 50 asthenoteratozoospermic men. Samples were divided into control and test groups for 2, 4 and 6 hr that the test group was incubated with VE (2 mM). In two groups, total motility, progressive motility and viability based on the WHO 2010 criteria were assessed. Moreover, malondialdehyde (MDA) levels were evaluated in each group. In the control group, total and progressive motility and sperm viability were decreased significantly after 2 hr; however, MDA levels were increased significantly after 6 hr. Also, in the test group, sperm parameters were increased significantly after 2 hr, and MDA levels were decreased significantly after 6 hr compared to the control group. In outcome, in vitro VE supplementation may protect spermatozoa from the adverse effect of oxidative stress during sperm preparation via preservation antioxidant processes in normal condition.  相似文献   
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β-Carbolines (BCs) are considered to be endogenous toxins and have been proposed as possible causative candidates inducing Parkinson's disease (PD). However, there is controversy about the effect and also effective dose of these compounds in the etiology of PD. This study was designed to further examine the effect of norharman (NH), a BC which in mammalian brain occurs at high levels in the substantia nigra, on the development of Parkinsonism-like behaviors in rats. A small amount (4μl) of NH solution at 2 or 200ng/ml was unilaterally injected into either striatum or substantia nigra (SN) by stereotaxic surgery. The development of Parkinsonism was assessed by three conventional behavioral tests, compared to the effects of unilateral 6-hydroxydopamine (6-OHDA) - induced lesions in the nigrostriatal pathway. An apomorphine-induced rotational test revealed no Parkinsonism-like behavior in the NH treated groups. However, rats that received the high concentration of NH into their SN showed significant biased swings in the elevated body swing test. In a rotarod test, NH treated groups showed relatively weak motor performance and their learning patterns were close to that of the 6-OHDA treated rats. Considering that the rotational test is only valid in animals with severe Parkinsonism, but time spent on the rotating rod correlates inversely with severity of Parkinsonism, our results indicate that a single exposure to low amounts of NH is effective in producing moderate Parkinsonism-like behavioral symptoms, possibly through a neurotoxic effect of this agent on the SN dopaminergic neurons.  相似文献   
3.
Pituitary - To review our institutional experience with the surgical management of prolactinomas through the endoscopic endonasal approach with specific focus on cavernous sinus invasion....  相似文献   
4.
BACKGROUNDPatients with p16+ oropharyngeal squamous cell carcinoma (OPSCC) are potentially cured with definitive treatment. However, there are currently no reliable biomarkers of treatment failure for p16+ OPSCC. Pathologist-based visual assessment of tumor cell multinucleation (MN) has been shown to be independently prognostic of disease-free survival (DFS) in p16+ OPSCC. However, its quantification is time intensive, subjective, and at risk of interobserver variability.METHODSWe present a deep-learning–based metric, the multinucleation index (MuNI), for prognostication in p16+ OPSCC. This approach quantifies tumor MN from digitally scanned H&E-stained slides. Representative H&E-stained whole-slide images from 1094 patients with previously untreated p16+ OPSCC were acquired from 6 institutions for optimization and validation of the MuNI.RESULTSThe MuNI was prognostic for DFS, overall survival (OS), or distant metastasis–free survival (DMFS) in p16+ OPSCC, with HRs of 1.78 (95% CI: 1.37–2.30), 1.94 (1.44–2.60), and 1.88 (1.43–2.47), respectively, independent of age, smoking status, treatment type, or tumor and lymph node (T/N) categories in multivariable analyses. The MuNI was also prognostic for DFS, OS, and DMFS in patients with stage I and stage III OPSCC, separately.CONCLUSIONMuNI holds promise as a low-cost, tissue-nondestructive, H&E stain–based digital biomarker test for counseling, treatment, and surveillance of patients with p16+ OPSCC. These data support further confirmation of the MuNI in prospective trials.FUNDINGNational Cancer Institute (NCI), NIH; National Institute for Biomedical Imaging and Bioengineering, NIH; National Center for Research Resources, NIH; VA Merit Review Award from the US Department of VA Biomedical Laboratory Research and Development Service; US Department of Defense (DOD) Breast Cancer Research Program Breakthrough Level 1 Award; DOD Prostate Cancer Idea Development Award; DOD Lung Cancer Investigator-Initiated Translational Research Award; DOD Peer-Reviewed Cancer Research Program; Ohio Third Frontier Technology Validation Fund; Wallace H. Coulter Foundation Program in the Department of Biomedical Engineering; Clinical and Translational Science Award (CTSA) program, Case Western Reserve University; NCI Cancer Center Support Grant, NIH; Career Development Award from the US Department of VA Clinical Sciences Research and Development Program; Dan L. Duncan Comprehensive Cancer Center Support Grant, NIH; and Computational Genomic Epidemiology of Cancer Program, Case Comprehensive Cancer Center. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH, the US Department of VA, the DOD, or the US Government.  相似文献   
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Sex differences are prominent influences on spatial performance. One of the most common tasks to assess sex differences in spatial navigation in rodents is the Morris water task (MWT). In this task rats swim in a pool of water to locate a hidden platform employing the topographical relationships among the distal visual cues, pool wall, and goal location. Some evidence suggests that male rats display superior performance relative to females in the MWT. It is unknown, however, to what extent the sex difference in rats is task-dependent. This study compared the performance of male and female Long-Evans rats in the wet-land MWT versus the dry-land ziggurat task (ZT). The ZT represents a new dry-land task in which rats explore an arena with 16 ziggurat pyramids to locate food rewards. Several behavioural parameters, including latency, path length, path speed, probe trial performance, errors, and the number of returns were used as indices of spatial learning and memory. While males and females did not display significant differences in the traditional measures of spatial navigation within MWT, they displayed a robust sex difference in all measures of the ZT. These results indicate task-specific sex differences in spatial performance. Our findings suggest that males and females may employ different learning strategies in the MWT and ZT and that the latter task provides a more favourable task for assessing sex differences in rats.  相似文献   
7.
PURPOSE: To report the clinical findings, treatment, outcomes, and histopathologic findings in patients with suspected orbital implant infection requiring implant removal. METHODS: Retrospective, observational case series of 14 patients (15 hydroxyapatite orbital implants) undergoing implant removal from September 1994 through December 2002. Patient age, type of surgery, implant type, symptoms, treatment, histopathology of implant, and follow-up course were analyzed. RESULTS: Of the 14 patients, 7 were female and 7 were male. The mean age at explantation was 42 years. The most common symptoms were discharge and socket tenderness. The most common signs were conjunctival inflammation (edema, hyperemia), discharge, and recurrent pyogenic granuloma. Clinical evidence of infection was documented in 13 patients. Histopathologic assessment of the 15 explanted implants showed acute inflammation and necrosis (abscess) with identification of microorganisms (5 patients), acute inflammation and necrosis without identification of microorganisms (4 patients), chronic inflammation with identification of microorganisms (1 patient), chronic inflammation without identification of microorganisms (3 patients), and a predominant foreign body granulomatous response without identification of microorganisms (2 patients). Osseous metaplasia was seen in 10 implants. Prompt resolution of symptoms and signs occurred in all but one case. CONCLUSIONS: The clinical course of porous orbital implant infection may be prolonged, and the early symptom of recurrent discharge, a common problem for implant recipients, may delay diagnosis. Implant infection should be suspected when there is persistent conjunctival inflammation and discharge after implant placement despite antibiotic therapy, discomfort on implant palpation, and recurrent pyogenic granuloma (indicative of implant exposure). Implant removal is usually required in these cases. If orbital pain (not necessarily related to implant palpation) is the main complaint, without signs of conjunctival inflammation and with or without discharge, one should consider other reasons for the symptoms.  相似文献   
8.
Objective: Brain abscesses continue to pose a problem in neurosurgery, and it is a serious life-threatening complication for several diseases. The objective of this research was to lock at the clinical profile of children suffering from brain abscess, predisposing conditions, microbiology and outcome of these patients. Methods: Ninety children aged less than 15 years were reviewed. The clinical presentation, predisposing factors, diagnosis, management and outcome were noted. There were 56( 62.2% ) males and 34 ( 37.7% ) females. The mean age of presentation was 5.7 ± 4.2 years. Results: The mean duration of illness at the time of presentation was 10.6 ± 12.4 days. Typically patients presented with fever, vomiting, headache, neurological deficit, and seizures. The predisposing conditions found were cyanotic congenital heart disease in 18 (20 % ) of children, meningitis in 6 (6.7 % ), Otitis or mastoiditis in 32 (35.5 % ), Head trauma in 6 ( 6.7 % ), previous intraeranial surgery in 8 (8.8 % ) and no underlying cause was found in 22 (24.4 % ) children. The most common microbe in children with cyanotic congenital heart disease was of the Streptococcus group (54 % ). Computerized tomography confirmed the diagnosis and the most common location of the abscess was the parietal lobe of the cerebral hemisphere. That abscesses were larger than 2 cm in diameter where aspirated surgically. Excision was performed for eight children. Six children expired, two due to intracranial bleeding and the others due to severe cerebral edema and tentorial herniation. Complications were observed in 11 children out of which six had squeal and five had bemiparesis. Conclusion: Attention to hygiene of mouth and teeth in infant and child patients with cyanotic heart disease is very important in prevention of infectious brain diseases. We must also pay attention to ear-nose-throat diseases of children. That is very important the patients be examined again after treatment because of finding and trea  相似文献   
9.
Objective To calculate couple-year of protection (CYP) by conversion coefficient (F) of tubectomy and vasectomy in urban and rural regions of Iran. Methods A total of 103 450 married women aged 10-49 years in 2005 across urban and rural regions of lran were sampled by multi stage cluster sampling. The data were collected by household survey and direct interview and analyzed by STATA8.0 software and survey analysis commands. Results Mean age of the women at the time of tubectomy estimated 31.9 years and conversion coefficient of tubectomy was 17.1 ±0.1. Mean age of women at the time of her husband vasectomy estimated 31.48 years and its conversion coefficient was 17. 5 ± 0. 1. Cluster analysis defined different regions of Iran on the basis of evaluated conversion coefficients of tubectomy and vasectomy which both of them presented seven clusters. Literacy of women and total coverage of family planning in a region had a direct relationship with this conversion coefficient (P〈0.05). Conclusion The variations observed in the conversion coefficients and their dissimilarity among different regions of Iran may be due to a variety of fundamental factors of which literacy and culture are of important factors.  相似文献   
10.
Spatial tasks are widely used to determine the function of limbic system structures in rats. The present study used a new task designed to evaluate spatial behavior, the ziggurat task (ZT), to examine the performance of rats with widespread hippocampal damage induced by N-methyl-d-aspartic acid (NMDA). The task consisted of an open field containing 16 identical ziggurats (pyramid shaped towers) arranged at equal distances. One of the ziggurats was baited with a food reward. The task required rats to navigate through the open field by using a combination of distal and/or proximal cues in order to locate the food reward. The ability to acquire and recall the location of the goal (baited) ziggurat was tested in consecutive training sessions of eight trials per day for 10 days. The location of the goal ziggurat was changed every second day, requiring the rats to learn a total of five different locations. Several parameters, including latency to find the target, distance traveled, the number of visits to non-baited ziggurats (errors), and the number of returns were used as indices of learning and memory. Control rats showed a significant decrease in distance traveled and reduced latency in locating the goal ziggurat across trials and days, suggesting that they learned and remembered the location of the goal ziggurat. Interestingly, the hippocampal-damaged group moved significantly faster, and traveled longer distances compared to the control group. Significant differences were observed between these groups with respect to the number of errors and returns on test days. Day 11 served as probe day, in which no food reward was given. The controls spent more time searching for the food in the previous training quadrant compared to the hippocampal group. The findings demonstrate that the ZT is a sensitive and efficient dry task for measuring hippocampus-dependent spatial performance in rats requiring little training and not associated with some of the disadvantages of water tasks.  相似文献   
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