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81.
JA Eekhof GH de Bock JA de Laat R Dap K Schaapveld MP Springer 《Canadian Metallurgical Quarterly》1996,46(409):473-474
Hearing loss is an important health problem in the elderly which sometimes leads to social isolation. In a study with 62 patients, the diagnostic value of four simple tests for screening for hearing loss in general practice was examined. When paying attention to the loudness of the whispering, the whispered voice test can be a valuable test for assessment of hearing loss in general practice. 相似文献
82.
83.
L Wubbel HS Jafri K Olsen S Shelton B Barton Rogers G Gambill P Patel E Keyser G Cassell GH McCracken 《Canadian Metallurgical Quarterly》1998,178(5):1526-1529
To investigate the pathogenesis of acute Mycoplasma pneumoniae infection, BALB/c mice were anesthetized with metofane, and M. pneumoniae was introduced intranasally on days 0, 1, and 2. Mice were sacrificed on days 0-15. A histopathologic scoring system defined inflammatory changes in the lungs on a scale of 0-26 (least to most severe). Broth cultures were positive for all nasal passage and bronchoalveolar lavage (BAL) specimens. Histopathologic scores ranged from 0 to 21. The mean log10 (cfu/mL) were 4.1-6.4 on days 1-10 and >/=1.7 on days 13-15 for nasal passage and BAL specimens. Serum polymerase chain reaction was negative. ELISA for serum IgM and immunoblots for M. pneumoniae antibody were positive in 21 (62%) of 34 and 33 (97%) of 34 infected animals, respectively, at days 8-15. ELISA for IgG antibody was negative. This mouse pneumonia model can be used to study the immunologic and therapeutic responses to acute M. pneumoniae infection. 相似文献
84.
BD Palmer JB Smaill M Boyd DH Boschelli AM Doherty JM Hamby SS Khatana JB Kramer AJ Kraker RL Panek GH Lu TK Dahring RT Winters HD Showalter WA Denny 《Canadian Metallurgical Quarterly》1998,41(27):5457-5465
1-Phenylbenzimidazoles are shown to be a new class of ATP-site inhibitors of the platelet-derived growth factor receptor (PDGFR). Structure-activity relationships (SARs) are narrow, with closely related heterocycles being inactive. A systematic study of substituted 1-phenylbenzimidazoles showed clear SARs. Substituents at the 4'- and 3'-positions of the phenyl ring are tolerated but do not significantly improve activity, while substituents at the 2'-position abolish it. Substituents in the 2-, 4-, and 7-positions of the benzimidazole ring (with the exception of 4-OH) also abolish activity. Most substituents at the 5- and 6-positions maintain or increase activity, with the 5-OH, 5-OMe, 5-COMe, and 5-CO2Me analogues being >10-fold more potent than the parent 1-phenylbenzimidazole. The 5-OMe analogue was both the most potent inhibitor, and showed the highest selectivity (50-fold) between PDGFR and FGFR isolated enzymes, and also a moderately effective inhibitor (IC50 = 1.9 microM) of PDGF-stimulated PDGFR autophosphorylation in rat aorta smooth muscle cells. 相似文献
85.
86.
Report on 4 patients with bilateral testicular tumours (out of a total number of 181 cases) and the problems arising with a second course of irradiation. The question of histogenesis and therapeutic course in 4 patients with a primary retroperitoneal tumour localization are discussed in the second part. 相似文献
87.
88.
TL Mullen M Kashgarian D Biemesderfer GH Giebisch TU Biber 《Canadian Metallurgical Quarterly》1976,231(2):501-508
The urinary bladder of Amphiuma exhibits stable transport properties and an electrical potential difference in vitro. The lumen is significantly negative to the serosa and under short-circuited conditions flux rations for Na and Cl of 5.92 +/- 0.42 and 1.81 +/- 0.20, respectively, were observed. The close agreement between the short-circuit current and net Na flux suggests that most, if not all, of the current is carried by Na. Both ouabain and amiloride decreased the short-circuit current and the mucosal-to-serosal (M leads to S) flux of Na. Furosemide caused a transient increase in the M leads to S flux of Na and Cl but ADH was without effect. In bladders that had high transmural resistance, a net movement of K in the M leads to S direction under short-circuited conditions with flux ratios of up to 2 could be observed. The epithelium of the Amphiuma bladder consists of three cell types: granular cells, basal cells, and mitochondria-rich cells. No goblet cells are present. The mitochondria-rich cells comprise less than 5% of the population of the surface epithelium in Amphiuma in contrast to other amphibian bladders, where it accounts for up to 25% of the population. 相似文献
89.
Ectopic bone was found in the interstitium of lungs of birds, guinea pigs and minks. There was no evidence of a relation between the ectopic bone and the occurrence of disease. 相似文献
90.