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Oligoclonal immunoglobulin G (IgG) bands are a frequent feature of inflammatory diseases of the central nervous system (CNS). In multiple sclerosis (MS), cerebrospinal fluid (CSF) oligoclonal IgG bands are a potential clue to the pathogenesis of the disease; however, their particular antigenic target is unknown. We sought to characterize the IgG response in an experimental CNS persistent demyelinating infection by isoelectric focusing (IEF) studies of serum and CSF from mice infected with Theiler's murine encephalomyelitis virus (TMEV). Following IEF, we used a new technique in order to identify TMEV-specific antibodies; focused immunoglobulins were blotted onto nitrocellulose paper which was then overlaid with radiolabeled virus. Autoradiograms showed that most of the TMEV antibody was locally synthesized within the CNS since CSF, but not serum, TMEV antibody had an anodal distribution. CSF IEF TMEV antibody spectrotypes were very similar, presumably because the CSFs were collected from the same inbred mouse strain. CSF TMEV antibody displayed less restricted heterogeneity than the very restricted cathodal CSF oligoclonal IgG bands seen in MS. The new IEF immunoblotting antigen overlay technique will be a powerful detection system to probe for the antigenic target against which MS CSF IgG may be directed.  相似文献   
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Spontaneously hypertensive rats (SHR) were more sensitive to the diabetogenic effects of streptozotocin than normotensive Wistar-Kyoto (WKY) rats. Thus, 10 days after intravenous administration of 25 mg/kg streptozotocin in SHR, mean pancreatic insulin content was decreased by 42% (p less than 0.05), and mean plasma glucose concentration was increased from 85 to 215 mg/dl (p less than 0.001), whereas between 37.5 and 50 mg/kg of streptozotocin was required to produce similar effects in normotensive WKY rats. Also, there was a progressive decrease in blood pressure in SHR injected with 25, 35.7, or 50 mg/kg of streptozotocin, whereas blood pressure was progressively increased after streptozotocin in normotensive WKY rats. The opposite effects of streptozotocin-induced diabetes on blood pressure in SHR and WKY rats could be observed at similar degrees of hyperglycemia and are presently unexplained.  相似文献   
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Introduction  The study was carried out to quantify the changes induced by the pandemic in plastic surgery practice and training and to study the impact of the webinars on plastic surgery education from a residents’ perspective. Methods  In this multicentric study, the number and type of surgeries, cause of injuries, and their regional variation during the coronavirus disease 2019 (COVID-19) period (February–September 2020) were compared with pre–COVID-19 time. An online survey on the impact of webinars was conducted for plastic surgery trainees across the country. Results  There was a significant reduction in total number of surgeries ( p = 0.003). The procedures for hand ( p = 0.156), faciomaxillary injuries ( p = 0.25), and replantations ( p = 0.46) were comparable; there was a significant reduction in combined orthopedic-plastic-surgical procedures ( p = 0.009) during the pandemic. There was a significant reduction in road accidents ( p = 0.007) and suicidal injuries ( p = 0.002) and increase in assault ( p = 0.03) and domestic accidents ( p = 0.01) during the COVID-19 period. A usefulness score of >8 was given for the webinars by 68.7% residents. There was no significant difference in perception of utility when correlated with the academic program at their institutes ( p = 0.109); 92% opined webinars should continue in post-COVID times. Conclusion  There was a drastic reduction in number of elective and emergency procedures during the COVID-19 time, negatively affecting resident training program. Majority of residents felt that webinars could prove a useful adjunct to training in formal training program in post-COVID-19 scenario.  相似文献   
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Introduction

The present review is based on the study of various classifications of pneumatization of temporal bone and their comparison. The air cells are classified based on their location in the temporal bone in a radiograph or based on their interpretation by a radiologist or otolaryngologist with the help of different reference structures.

Methods

The analysis of pneumatization in temporal bone is done by reviewing research articles related to pneumatization of temporal bone in pig, sheep, macaque and humans published in Pubmed, Sciencedirect, Scopus, and Medline, Indexed journals.

Results and discussion

According to classical classification the temporal bone is divided into five regions viz., middle ear, squamomastoid(mastoid), perilabyrinthine, petrous apex and accessory. The cells are named accordingly and they are further classified into various grades by the degree of pneumatization and density of cells present in the respective regionsMost recent work which has been cited in various articles, is done by Han et al. [19] In this pneumatization is classified based on the visualization of various reference structures such as, sigmoid sinus, labyrinth, and internal carotid artery. The lack of consensus among surgeons and otolaryngologists regarding the classification of the pneumatization of temporal bone may be a cause of failure in a few otologic surgeries such as 10 mastoidectomies etc and postoperative care of skull base surgeries.  相似文献   
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We have evaluated the effect of variation in aryl-tetralin lignans on the radioprotective properties of Podophyllum hexandrum. Two fractionated fractions of P. hexandrum [methanolic (S1) and chloroform fractions (S2)], with varying aryl-tetralin lignan content were utilized for the present study. The peroxyl ion scavenging potentials of S1 and S2 were found to be comparable [i.e. 45.88% (S1) and 41% (S2)] after a 48 h interval in a time-dependent study, whereas in a 2 h study, S2 exhibited significant (P < 0.05) antioxidant activity in different metal ion + flux states. In the aqueous phase, S2 exhibited non-site-specific reactive oxygen species scavenging activity, i.e. 73.12% inhibition at 500 mug ml(-1). S1 exhibited 58.40 +/- 0.8% inhibition (at 0.025 mug ml(-1)) of the formation of reactive nitrite radicals, comparable to S2 (52.45 +/- 0.825%), and also showed 45.01% site-specific activity (1000 mug ml(-1)), along with significant (P < 0.05) electron donation potential (50-2000 mug ml(-1)) compared to S2. Such activities of S1 could be attributed to the significantly (P < 0.05) higher levels of podophyllotoxin beta-d-glucopyranoside (16.5 times) and demethyl podophyllotoxin glucoside (2.9 times) compared with S2. Together, these findings clearly prove that aryl-tetralin lignan content influences the radiation protective potential of the Podophyllum fractions to a great extent.  相似文献   
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