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991.
992.

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   
993.
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   
994.
Five-week-old BNL male mice were maintained on a 12-h light/dark cycle, subcutaneously injected with [3H]-thymidine 1 h before death and killed every 3 h for 24 h. Autoradiographs were made from demineralized, paraffin-wax embedded sagittal sections of maxillae. The labelling index was calculated for fibroblast-like cells of the periodontal ligament mesial to the first molar. A bimodal distribution of labelled cells was seen. Labelling index was highest at 0900 h (light period); a second, lower, peak was seen at 2400 h (dark period). Cell proliferation was significantly increased during the light period. The increased activity during the dark period may represent a superimposed secondary, ultradian, rhythm, differences in periodontal cell subtypes or may be related to the feeding and activity cycle of the mouse. Thus there is a 24-h cyclic rhythmicity in the proliferation of periodontal-ligament cells in the mouse.  相似文献   
995.
996.
Polyphenolic extracts of the principal flavonoid classes present in cranberry were screened in vitro for cytotoxicity against solid tumor cells lines, identifying two fractions composed principally of proanthocyanidins (PACs) with potential anticancer activity. Matrix‐Assisted Laser Desorption/Ionization Time‐Of‐Flight Mass Spectrometry (MALDI‐TOF‐MS) analysis of the proanthocyanidins (PACs) fractions indicated the presence of A‐type PACs with 1–4 linkages containing between 2–8 epicatechin units with a maximum of 1 epigallocatechin unit. PACs exhibited in vitro cytotoxicity against platinum‐resistant human ovarian, neuroblastoma and prostate cancer cell lines (IC50 = 79–479 µg/mL) but were non‐cytotoxic to lung fibroblast cells (IC50 > 1000 µg/ml). SKOV‐3 ovarian cancer cells treated with PACs exhibited classic apoptotic changes. PACs acted synergistically with paraplatin in SKOV‐3 cells. Pretreatment of SKOV‐3 cells with PACs (106 µg/ml) resulted in a significant reduction of the paraplatin IC50 value. Similarly, in a BrdU incorporation assay, co‐treatment of SKOV‐3 cells with PACs and paraplatin revealed reduced cell proliferation at lower concentrations than with either individually. In SKOV‐3 cell cultures co‐treated with PAC‐1 and paraplatin, an HPLC analysis indicated differential quantitative presence of various PAC oligomers such as DP‐8, ‐9, ‐11 and ‐14 indicating either selective binding or uptake. Cranberry proanthocyanidins exhibit cell‐line specific cytotoxicity, induce apoptotic markers and augment cytotoxicity of paraplatin in platinum‐resistant SKOV‐3 ovarian cancer cells. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
997.
BACKGROUND New onset hyperglycemia is common in patients with severe coronavirus disease 2019(COVID-19) infection. Cytokine storm due to COVID-19 infection is an essential etiology for new-onset hyperglycemia, but factors like direct severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-induced pancreatic β-cell failure have also been postulated to play a role.AIM We plan to investigate further the mechanisms underlying SARS-CoV-2 infectioninduced hyperglycemia, particularly the rationale ...  相似文献   
998.
999.
The effect of boswellic acids on bovine serum albumin (BSA)-induced arthritis in rabbits was studied. Oral administration of boswellic acids (25, 50 and 100 mg/kg/day) significantly reduced the population of leucocytes in a BSA-injected knee and changed the electrophoretic pattern of the synovial fluid proteins. The local injection of boswellic acids (5, 10 and 20 mg) into the knee 15 min prior to BSA challenge also significantly reduced the infiltration of leucocytes into the knee joint, reduced the infiltration of leucocytes into the pleural cavity and inhibited the migration of PMN in vitro. The leucocyte-inhibitory activity of boswellic acids was not due to its cytotoxic effect. The boswellic acids did not show any detergent or surfactant properties.  相似文献   
1000.
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