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JAROSLAV KAŠPAR IGOR KOROPECKÝ EDUARD BRYNDA STANISLAV NEŠPUdotREK 《International Journal of Electronics》2013,100(5):1041-1042
Langmuir-Blodgett films have been prepared from copper tetra-4-t-butylphthalocyanine. A voltage dependence of capacitance can be attributed to the presence of a Schottky depletion layer. The barrier potential was determined as l·4eV, and the carrier concentration about 1024m?3 相似文献
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KA Head 《Canadian Metallurgical Quarterly》1999,4(1):10-22
Ipriflavone, an isoflavone synthesized from the soy isoflavone daidzein, holds great promise in the prevention and treatment of osteoporosis and other metabolic bone diseases. It has been widely studied in humans and found effective for inhibiting bone resorption and enhancing bone formation, the net result being an increase in bone density and a decrease in fracture rates in osteoporotic women. While ipriflavone appears to enhance estrogen's effect, it does not possess intrinsic estrogenic activity, making it an attractive adjunct or alternative to conventional hormone replacement therapy. Preliminary studies have also found ipriflavone effective in preventing bone loss associated with chronic steroid use, immobility, ovariectomy, renal osteodystrophy, and gonadotrophin hormone-releasing hormone agonists. In addition, it holds promise for the treatment of other metabolic diseases affecting the bones, including Paget's disease of the bone, hyperparathyroidism, and tinnitus caused by otosclerosis. 相似文献
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G He J Hart OS Kim GL Szot CT Siegel JR Thistlethwaite KA Newell 《Canadian Metallurgical Quarterly》1999,67(1):131-137
Studies were performed to determine the effects of PTH and related compounds on phosphatidylcholine (PC) hydrolysis in UMR-106 cells and the pathway by which the PTH effects occurred. The responses were compared with those of phorbol 12,13-dibutyrate (PDBu). Both bovine PTH-(1-34) [bPTH-(1-34)] and PDBu stimulated PC hydrolysis within 10 min. Significant effects were elicited by concentrations of 0.3-1 nM bPTH-(1-34) and 5 nM PDBu. Dose-dependent increases were seen at higher concentrations of both compounds, however, the response to bPTH-(1-34) was reduced at 30 nM. Bovine or human PTH-(1-34) and human PTH-related peptide-(1-34) [hPTHrP-(1-34)] were equipotent in their effects, whereas bovine [Nle(8,18)Tyr34]PTH-(3-34) amide [bPTH-(3-34)] and hPTH-(1-31) amide [hPTH-(1-31)] were less potent than bPTH-(1-34). bPTH-(3-34) did not antagonize the effects of bPTH-(1-34). Down-regulation of protein kinase C isozymes by 24-h treatment with PDBu completely prevented the stimulatory effect of PDBu on PC hydrolysis, but did not significantly affect the stimulatory effect of bPTH-(1-34). Both bPTH-(1-34) and PDBu stimulated transphosphatidylation of PC, indicating a phospholipase D-stimulated mechanism. The results suggest that in the UMR-106 cell line PTH can stimulate activation of PLD by a mechanism other than through protein kinase C. 相似文献
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O Hobert DG Moerman KA Clark MC Beckerle G Ruvkun 《Canadian Metallurgical Quarterly》1999,144(1):45-57
The glycosylation of the equine interhaemal barrier and areola was studied throughout the period of gestation. Placentae of 35, 37, 50, 119, 152, 200, 280 and 300 days gestation were investigated, using semithin plastic embedded sections and a panel of 15 biotinylated lectins with an avidin-peroxidase revealing system. Glycosylation of the trophoblast and maternal epithelium showed the most change during the first 50 days of gestation, being associated with the initial stages of adhesion and attachment. In the trophoblast, non-bisected tri/tetraantennary complex N-glycan was only evident after day 37 and terminal N-acetyl galactosamine, alpha2,3- and alpha2,6-linked sialic acids disappeared at the same time. The areolar trophoblast exhibited some differences from microcotyledonary areas, especially with respect to 2-deoxy, 2-acetamido alpha-galactose and tri/tetraantennary, non-bisected complex N-glycan, suggesting that the differences in function between microcotyledonary and areolar trophoblast are reflected at both the morphological and the biochemical level. Granules of the maternal uterine epithelium bound many lectins, particularly those with specificity for bisected and non-bisected bi/triantennary N-linked glycan, 2-deoxy, 2-acetamido alpha-galactosyl, beta-galactosyl and some fucosylated termini. Binding to sialic acids in alpha2,3- and alpha2,6-linkage was sparse. Maternal and fetal capillaries showed little change in glycan expression over the period studied, being rich in bisected and non-bisected bi/triantennary N-linked glycan and sialic acids, with some terminal N-acetyl galactosamine and no detectable terminal fucosyl residues. 相似文献
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KA Birkness M Deslauriers JH Bartlett EH White CH King FD Quinn 《Canadian Metallurgical Quarterly》1999,67(2):653-658
A tissue culture bilayer system that mimics some aspects of early alveolar infection by Mycobacterium tuberculosis was developed. This model incorporates human lung epithelial type II pneumocyte (A549) (upper chamber) and endothelial cell (lower chamber) layers separated by a microporous membrane. This construction makes it possible to observe and quantify the passage of bacteria through the two layers, to observe the interaction of the bacteria with the various cell types, and to examine the basic mechanisms of immune cell recruitment to the site of infection. After 10(7) organisms were added to the upper chamber we microscopically observed large numbers of bacteria attached to and within the pneumocytes and we determined by viable-cell counting that a small percentage of the inoculum (0.02 to 0.43%) passed through the bilayer into the lower chamber. When peripheral blood mononuclear cells were added to the lower chamber, microscopic examination indicated a migration of the mononuclear cells through the bilayer to the apical surface, where they were seen associated with the mycobacteria on the pneumocytes. The added complexity of the bilayer system offers an opportunity to define more precisely the roles of the various lung cell types in the pathogenesis of early tuberculosis. 相似文献
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Recovery of health related quality of life in the year after radical prostatectomy: early experience
PURPOSE: We determined the temporal course of patient return to baseline quality of life after treatment with radical prostatectomy for early stage prostate cancer. MATERIALS AND METHODS: After establishing a longitudinal observational database of men undergoing radical retropubic prostatectomy we used established, validated quality of life questionnaires (RAND 36-Item Health Survey and University of California, Los Angeles Prostate Cancer Index) to document changes in general and disease specific health related quality of life (HRQOL). We assessed 90 patients at baseline before surgery and then at 3-month intervals for 1 year postoperatively. Logistic regression was used to explore predictors of the return to baseline. RESULTS: After prostatectomy patients had a significant decrease in all domains of HRQOL. Return to baseline was rapid in the general and bowel domains with at least two-thirds to three-fourths of patients reaching pretreatment levels within 6 months of surgery. Return to baseline was slower in the urinary and sexual function domains with 61 and 31% of the men, respectively, reaching pretreatment levels by 1 year after surgery. Of those who reached baseline the average intervals for the bowel, sexual and urinary domains were 5, 6 and 7 months, respectively. Married and white patients were more likely to achieve a return to baseline HRQOL during year 1 postoperatively. However, education level was inversely associated with the likelihood of returning to baseline. CONCLUSIONS: During the year after radical prostatectomy for early stage prostate cancer patient quality of life steadily improved. By 3 months postoperatively 30 to 40% of the patients had already recovered baseline levels of physical, mental and social functioning, and by 6 months more than 70% had reached baseline in the general HRQOL domains. By 12 months after surgery 86 to 97% of the patients had returned to baseline levels in each domain. Each domain continued to improve throughout the year. For the patients who reached baseline general HRQOL during followup average recovery time was 5 to 6 months. 相似文献
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MA Mansour FN Littooy WC Watson KA Blumofe TJ Heilizer GF Steffen C Chmura SS Kang N Labropoulos HP Greisler SG Fisher WH Baker 《Canadian Metallurgical Quarterly》1999,29(2):217-25; discussion 225-7
PURPOSE: The incidence rate of disease progression and stroke after the diagnosis of a moderate (50% to 79%) carotid stenosis was determined by means of color-flow duplex scanning. METHODS: During a 4-year period, 344 male veterans with moderate internal carotid artery stenoses, on one or both sides, were examined at regular intervals for a mean period of 25 months. Carotid color-flow scans were obtained semiannually. Clinical follow-up was performed to determine the incidence rate of amaurosis fugax, transient ischemic attacks, nonhemispheric symptoms, and strokes. RESULTS: New neurologic symptoms developed in 75 patients (21.8%). Fifty-one (14.8%) had ipsilateral symptoms during follow-up: 18 amaurosis fugax (5.2%), 14 transient ischemic attacks (4%), 5 nonhemispheric symptoms (1.4%), and 14 strokes (4%). Twenty-four patients (6.9%) had contralateral symptoms: 20 strokes (5.8%) and 4 transient ischemic attacks (1.2%). Life-table analysis showed that the annual rate of ipsilateral neurologic events was 8.1%, and the annual rate of stroke was 2.1%. Seventy-five patients (22%) died in the follow-up period. Disease progression to 80% to 99% stenosis or occlusion occurred in 71 of 458 vessels (15.5%). The internal carotid arteries that showed evidence of disease progression had a significantly higher initial peak systolic velocity (251 vs 190 cm/s; P <.0001) and end diastolic velocity (74 vs 52 cm/s; P < 0.0001). Black patients and patients with ischemic heart disease were at a higher risk for disease progression. We could not identify any atherosclerotic risk factors that reliably predicted patients in whom future ipsilateral neurologic symptoms were more likely to develop. However, there was an increased risk of stroke associated with progression of disease. CONCLUSION: Patients who are asymptomatic and who have moderate carotid stenoses are at significant risk for neurologic symptoms and death, but have a relatively low incidence rate of ipsilateral events. The initial flow characteristics in the stenotic vessel are predictive of future disease progression, but they are not helpful in identifying patients in whom symptoms will develop. 相似文献