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The aim of this study is to identify the effect of time and pressure of tourniquet in blood pressure and pulse rate immediately after the releasing of tourniquet in the upper and lower extremity of the orthopedic surgeries. This retrospective study examined 206 consecutive patients. Comparisons of the systolic and diastolic pressure and heart rate were made before the induction of anesthesia and tourniquet inflation, and immediately after the deflation. In general, there was no significant difference in hemodynamic changes between the upper- and lower-limb with regard to the type of anesthesia. There was no significant correlation between systolic blood pressure and tourniquet pressure, while by increasing the tourniquet time significantly, the systolic blood pressure decreases immediately after the deflation. Interestingly, the considerable increase in age paralleled with a significant decrease in the systolic blood pressure. The effect of tourniquet time is more than the age. There was no significant correlation between the tourniquet pressure and tourniquet time with diastolic blood pressure. Simply the increase in age significantly paralleled with the mild decrease in diastolic blood pressure Orthopedic surgeons are recommended not to rely on the benefits of tourniquet to raise blood pressure due to hypotensive conditions after the deflation especially in the old.  相似文献   
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We report on a novel localization for a recessive form of deafness (DFNB), by linkage analysis in an Iranian consanguineous family. Affected individuals suffer from prelingual profound sensorineural hearing loss. Genome-wide analysis led to the characterization of a new locus, DFNB40, which maps to an approximately 9 Mb interval between markers D22S427 and D22S1144 at chromosome 22q11.21-12.1. Maximum lod score of 3.09 was obtained with D22S1174. Since the Bronx waltzer (bv) mouse mutant, characterized by waltzing behavior, deafness, and degeneration of cochlear inner hair cells, has been mapped to the syntenic region on murine chromosome 5, we suggest that DFNB40 and bv may result from orthologous gene defects.  相似文献   
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F Shafa  S Hamedi  E Meisami  R Mousavi 《Neuroscience》1980,5(8):1467-1474
Monolateral removal of the olfactory bulb and the olfactory penduncular structures in the neonatal rat resulted in a profound morphological and biochemical asymmetry between the two hemispheres. The experimental hemisphere, ipsilateral to the lesion, protruded into the space normally occupied by the olfactory bulb and showed enlarged ventricles. The brain loci were displaced rostrally in this hemisphere.The desoxyribonucleic acid, ribonucleic acid and protein contents of the experimental hemisphere at 25 and 60 days of age were all significantly lower than that found in the control hemisphere contralateral to the lesion.To resolve between the two possible causes of this asymmetry (i.e. atrophy of the experimental or hypertrophy of the control hemisphere) hemispheres of the asymmetric brain were compared with homonymous hemispheres of unoperated normal rats. This comparison revealed that the asymmetry is basically due to an excess of desoxyribonucleic acid synthesis in the control hemisphere, which continues even after postnatal day 25, on the one hand, and a dearth of protein in the experimental hemisphere on the other. This finding implies two separate mechanisms for the processes that underlie the asymmetries observed for these two substances.Our results demonstrate two important characteristics of the developing brain. Firstly they indicate that removal of the olfactory bulb and the olfactory peduncle can produce considerable changes in the hemispheres, and secondly they unravel the strong latent potential of the brain for cell proliferation beyond the usual period of cell division in the brain. As in these experiments regulation of cell division is affected, this system might serve as a model for the study of aberrant cell division found in tumor formation and the process of carcinogenesis.  相似文献   
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Testicular torsion is a dangerous urogenital disorder which is caused by twisting of spermatic cord, and unless immediate treatments happen at a proper time, oxidative stress, occurred during ischaemia reperfusion, finally leads to irreversible disintegration of testicular tissue. One of the first preventive lines is to administrate antioxidant factors. In the present study, we investigate the therapeutic effect of cerium oxide nanoparticle on the injury. We divided 45 rats into nine groups, subjected eight groups to testicular torsion–detorsion, injected different doses of cerium oxide nanoparticle into the peritoneum of six groups and analysed all the groups regarding spermatogenetic indices including sperm count, sperm viability and Johnson mean. Our results showed that cerium oxide nanoparticle can alleviate oxidative stress in testis, and this alleviation promotes the reproductive indices as the concentration of cerium oxide nanoparticles increases. The catalase-mimetic and superoxide dismutase-mimetic activities of cerium oxide nanoparticle are the most probable theories to explain the antioxidant effect of the nanoparticle.  相似文献   
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IntroductionMultiparametric magnetic resonance imaging (mpMRI) has resulted in accurate prostate cancer localization and image-guided targeted sampling for biopsy. Despite its more recent uptake, knowledge gaps in interpretation and reporting exist. Our objective was to determine the need for an educational intervention among urology residents working with mpMRIs.MethodsWe administered an anonymous, cross-sectional, self-report questionnaire to a convenience sample of urology residents in U.S. and Canadian training programs. The survey included both open- and closed-ended questions employing a five-point Likert scale. It was designed to assess familiarity, exposure, experience, and comfort with interpretation of mpMRI.ResultsFifty-three surveys were completed by residents in postgraduate years (PGY) 1–5 and of these, only 12 (23%) reported any formal training in mpMRI interpretation. Most residents’ responses demonstrated significant experience with prostate biopsies, as well as familiarity with reviewing mpMRI for these patients. However, mean (± standard deviation [SD]) Likert responses suggested a relatively poor understanding of the components of Prostate Imaging-Reporting and Data System (PI-RADS) v2 scoring for T2-weighted films (2.45±1.01), diffusion-weighted imaging (DWI) films (2.26±0.90), and dynamic contrast-enhanced (DCE) films (2.21±0.99). Similar disagreement scores were observed for questions around interpretation of the different functional techniques of MRI images. Residents reported strong interest (4.21±0.91) in learning opportunities to enhance their ability to interpret mpMRI.ConclusionsWhile mpMRI of the prostate is a tool frequently used by care teams in teaching centers to identify suspicious prostate cancer lesions, there remain knowledge gaps in the ability of trainees to interpret images and understand PI-RADS v2 scoring. Online modules were suggested to balance the needs of trainee education with the residency workflow.  相似文献   
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OBJECTIVE: The aim of this study was to evaluate the probable usefulness of normal beta-human chorionic gonadotropin (beta-hCG) regression curve in the diagnosis of persistent trophoblastic disease (PTD). METHODS: A log-value regression curve was developed from the means and 95% confidence limits of serial weekly serum beta-hCG titers of 43 patients with uneventful complete hydatidiform moles and 14 patients, who were previously confirmed as PTD. RESULTS: All 14 PTD patients (100%) had abnormal values, beyond normal range, within 4 weeks. beta-hCG was in its upper values, compared to normal regression curve at 2.29 +/- 0.19 weeks. This was earlier than plateau or rise detection at 4.21 +/- 0.33 weeks (P < 0.001). Within 3 weeks of evacuation, 13 of 14 (92.86%) PTD patients' beta-hCG values exceeded the normal range, whereas only six of 14 (42%) showed a rise or plateau. CONCLUSION: Our finding indicates that the normal beta-hCG regression curve may be useful for quicker detection of PTD than the plateau or rise of level.  相似文献   
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The respiratory system was primarily considered the only organ affected by Coronavirus disease 2019 (COVID-19). As the pandemic continues, there is an increasing concern from the scientific community about the future effects of the virus on male and female reproductive organs, infertility, and, most significantly, its impact on the future generation. The general presumption is that if the primary clinical symptoms of COVID-19 are not controlled, we will face several challenges, including compromised infertility, infection-exposed cryopreserved germ cells or embryos, and health complications in future generations, likely connected to the COVID-19 infections of parents and ancestors. In this review article, we dedicatedly studied severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) virology, its receptors, and the effect of the virus to induce the activation of inflammasome as the main arm of the innate immune response. Among inflammasomes, nucleotide oligomerization domain-like receptor protein, pyrin domain containing 3 (NLRP3) inflammasome pathway activation is partly responsible for the inflicted damages in both COVID-19 infection and some reproductive disorders, so the main focus of the discussion is on NLRP3 inflammasome in the pathogenesis of COVID-19 infection alongside in the reproductive biology. In addition, the potential effects of the virus on male and female gonad functions were discussed, and we further explored the potential natural and pharmacological therapeutic approaches for comorbidity via NLRP3 inflammasome neutralization to develop a hypothesis for averting the long-term repercussions of COVID-19. Since activation of the NLRP3 inflammasome pathway contributes to the damage caused by COVID-19 infection and some reproductive disorders, NLRP3 inflammasome inhibitors have a great potential to be considered candidates for alleviating the pathological effects of the COVID-19 infection on the germ cells and reproductive tissues. This would impede the subsequent massive wave of infertility that may threaten the patients.  相似文献   
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