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Cerumen impaction represents the most common otologic problem encountered by physicians. It can affect up to 6% of the general population and a much higher percentage in the mentally retarded population. Cerumen is a mixture of secretory products of two glands in the external auditory canal where it serves a protective function. The external auditory canal possesses a unique anatomy and physiology that permits an efficient self-cleaning system. In most cases, a breakdown in the epithelial migration of the external auditory canal is thought to cause cerumen impaction. The management of cerumen impaction include direct removal, irrigation, and the use of cerumenolytics. 相似文献
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RG Sachs 《Canadian Metallurgical Quarterly》1986,33(11):3283-3292
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CE Ferreira SG Grossi AB Novaes RG Dunford EJ Feres-Filho 《Canadian Metallurgical Quarterly》1997,17(3):250-259
The aim of this study was to determine the effect of subgingival scaling and root planing on healing of the distal surface of second molars following extraction of third molars. Twenty-eight patients with contralateral erupted third molars and pocket depths greater than or equal to 3 mm on the distal surface of the second molars participated in this study. Measurements of supragingival bacterial plaque, bleeding on probing, pocket depth, and relative attachment level were performed at baseline and 2 months after treatment. Extraction of contralateral third molars was carried out simultaneously. The experimental site received thorough scaling and root planing of the distal surface of the second molar, while the control site received extraction alone. Experimental sites showed significant improvement in all clinical parameters assessed compared to the control sites. In conclusion, periodontal lesions on the distal of second molars can be significantly improved following scaling and root planing after extraction of third molars. 相似文献
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KONRAD WEIDENDORFER ANDREA BIENIAS JÖRG HINRICHS 《International Journal of Dairy Technology》2008,61(4):379-384
Texture properties of stirred low‐fat yogurt were investigated in terms of processing after fermentation. The yogurt gel was pumped through a colloid mill at two gap widths and various peripheral velocities of the rotor. The storage modulus and yield stress were measured after 1 day and after 3 weeks, and the occurrence of syneresis was noted. The main factor for the structural degradation in the shear gap was the mean peripheral velocity of the rotor, rather than the apparent shear rate. Syneresis is related to a certain level of the storage modulus. The yield stress correlated with the storage modulus. 相似文献
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M Simons S Beinroth M Gleichmann P Liston RG Korneluk AE MacKenzie M B?hr T Klockgether GS Robertson M Weller JB Schulz 《Canadian Metallurgical Quarterly》1999,72(1):292-301
The inhibitor of apoptosis (IAP) family of antiapoptotic genes, originally discovered in baculovirus, exists in animals ranging from insects to humans. Here, we investigated the ability of IAPs to suppress cell death in both a neuronal model of apoptosis and excitotoxicity. Cerebellar granule neurons undergo apoptosis when switched from 25 to 5 mM potassium, and excitotoxic cell death in response to glutamate. We examined the endogenous expression of four members of the IAP family, X chromosome-linked IAP (XIAP), rat IAP1 (RIAP1), RIAP2, and neuronal apoptosis inhibitory protein (NAIP), by semiquantitative reverse PCR and immunoblot analysis in cultured cerebellar granule neurons. Cerebellar granule neurons express significant levels of RIAP2 mRNA and protein, but expression of RIAP1, NAIP, and XIAP was not detected. RIAP2 mRNA content and protein levels did not change when cells were switched from 25 to 5 mM potassium. To determine whether ectopic expression of IAP influenced neuronal survival after potassium withdrawal or glutamate exposure, we used recombinant adenoviral vectors to target XIAP, human IAP1 (HIAP1), HIAP2, and NAIP into cerebellar granule neurons. We demonstrate that forced expression of IAPs efficiently blocked potassium withdrawal-induced N-acetyl-Asp-Glu-Val-Asp-specific caspase activity and reduced DNA fragmentation. However, neurons were only protected from apoptosis up to 24 h after potassium withdrawal, but not at later time points, suggesting that IAPs delay but do not block apoptosis in cerebellar granule neurons. In contrast, treatment with 100 microM or 1 mM glutamate did not induce caspase activity and adenoviral-mediated expression of IAPs had no influence on subsequent excitotoxic cell death. 相似文献
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The primary objective of this investigation was to determine the effect of endotoxin on islet xenograft survival within the first three days after transplantation. Pancreatic islets from Lewis rats were prepared under endotoxin-free conditions with Liberase (Boehringer) and purified by centrifugation on endotoxin-free Ficoll/Histopaque. After overnight incubation, with or without 10 microg/ml endotoxin, the islets were transplanted beneath the kidney capsule of normoglycemic C57Bl/6-mice. Three days later, kidneys were removed and their insulin content were measured. We could demonstrate significant differences (P<0.01) in insulin recovery between lipopolysaccharide-free and lipopolysaccharide-containing grafts. In case of endotoxin contaminated islets, we found only 13+/-2% (n=9) of the original insulin content, in contrast to 53+/-7% (n=9) when endotoxin-free islets where grafted. In experiments with islets isolated by use of conventional (lipopolysaccharide-containing) collagenase, and then cultured in endotoxin-free medium, insulin recovery three days after transplantation was 36+/-1% (n=13). 相似文献