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61.
62.
BP Thomma K Eggermont IA Penninckx B Mauch-Mani R Vogelsang BP Cammue WF Broekaert 《Canadian Metallurgical Quarterly》1998,95(25):15107-15111
The endogenous plant hormones salicylic acid (SA) and jasmonic acid (JA), whose levels increase on pathogen infection, activate separate sets of genes encoding antimicrobial proteins in Arabidopsis thaliana. The pathogen-inducible genes PR-1, PR-2, and PR-5 require SA signaling for activation, whereas the plant defensin gene PDF1.2, along with a PR-3 and PR-4 gene, are induced by pathogens via an SA-independent and JA-dependent pathway. An Arabidopsis mutant, coi1, that is affected in the JA-response pathway shows enhanced susceptibility to infection by the fungal pathogens Alternaria brassicicola and Botrytis cinerea but not to Peronospora parasitica, and vice versa for two Arabidopsis genotypes (npr1 and NahG) with a defect in their SA response. Resistance to P. parasitica was boosted by external application of the SA-mimicking compound 2, 6-dichloroisonicotinic acid [Delaney, T., et al. (1994) Science 266, 1247-1250] but not by methyl jasmonate (MeJA), whereas treatment with MeJA but not 2,6-dichloroisonicotinic acid elevated resistance to Alternaria brassicicola. The protective effect of MeJA against A. brassicicola was the result of an endogenous defense response activated in planta and not a direct effect of MeJA on the pathogen, as no protection to A. brassicicola was observed in the coi1 mutant treated with MeJA. These data point to the existence of at least two separate hormone-dependent defense pathways in Arabidopsis that contribute to resistance against distinct microbial pathogens. 相似文献
63.
The activities of antimicrobial combinations from three geographically diverse skin/tissue banks used in the processing of skin/ tissue were compared using bacteria and yeast isolated from burn patients. All formulations showed 90% or more effectiveness against bacteria generally susceptible to antibiotics but were less effective (60-80%) when tested against bacteria resistant to specific antimicrobials. Anti-yeast activity was present when an appropriate antifungal agent was included in the combination. All formulations were stable for at least six weeks. Results of this study raise certain questions about the use of these antimicrobial combinations in contemporary skin/tissue banking and point the way toward areas for future study. 相似文献
64.
DL Broyles RG Nielsen EM Bussett WD Lu IA Mizrahi PA Nunnelly TA Ngo J Noell RH Christenson BC Kress 《Canadian Metallurgical Quarterly》1998,44(10):2139-2147
The performance characteristics of the Tandem-MP Ostase assay, a new microplate immunoassay for bone-specific alkaline phosphatase (bone ALP; EC 3.1.3.1) in human sera, are described. Bone ALP is bound to streptavidin-coated microwells by a single biotinylated anti-bone ALP monoclonal antibody. Antigen is detected by the addition of p-nitrophenyl phosphate. The assay is performed at room temperature in <90 min. Imprecision was 2.3-6.1% with a detection limit of 0.6 microg/L. Method comparison of bone ALP measurements with the Tandem-MP Ostase assay and the mass-based Tandem-R Ostase assay (n = 285) indicated regression statistics of Tandem-MP Ostase = 1.03 Tandem-R Ostase + 0.22 microg/L, S(y/x) = 4.0 microg/L, r = 0.97. Serum bone ALP values in apparently healthy men and in pre- and postmenopausal women were also similar between the two Ostase assay formats. Liver ALP reactivity determined using the slope and heat inactivation methods was similar in both Ostase assays. Liver ALP reactivity ranged from 3 microg/L (heat inactivation) to 6 microg/L (slope method) per 100 U/L of liver ALP activity, whereas bone ALP reactivity was 37 microg/L per 100 U/L of bone ALP activity, indicating a liver ALP relative reactivity of 8.1-16.2%. Similar results were obtained with the Alkphase-B bone ALP immunoassay. The Tandem-MP Ostase bone ALP assay demonstrated increased concentrations of serum bone ALP in conditions where bone metabolism is increased and showed a rapid, temporal decrease in serum bone ALP in Paget disease patients on bisphosphonate therapy. In conclusion, the Tandem-MP Ostase assay for serum bone ALP is a rapid, simple, robust nonisotopic alternative to the Tandem-R Ostase immunoradiometric assay that provides an accurate and sensitive assessment of bone turnover. 相似文献
65.
66.
Aneurysms of any size involving the A1 segment of the anterior cerebral artery are unusual, but giant aneurysms in this location are exceedingly rare, with only five cases previously reported in the literature. We report three cases of A1 segment giant aneurysms presenting with mass effect that were successfully treated. A discussion of the salient features of diagnosis and treatment are presented, along with a brief review of the literature describing these aneurysms. The role of newer imaging modalities, including magnetic resonance imaging, magnetic resonance angiography, and intraoperative angiography, is discussed. The three patients were treated by direct exploration, trapping, and endaneurysmal decompression. Giant A1 segment aneurysms present a unique opportunity to safely trap and decompress the aneurysm with definitive cure. 相似文献
67.
EW van Etten SV Snijders W van Vianen IA Bakker-Woudenberg 《Canadian Metallurgical Quarterly》1998,42(9):2431-2433
In leukopenic mice with severe systemic candidiasis, single-dose treatment (5 mg of amphotericin B [AMB]/kg of body weight) with long-circulating polyethylene glycol-coated AMB liposomes (PEG-AMB-LIP) resulted in zero mortality and a significant reduction in the number of viable Candida albicans in the kidney, whereas 70% mortality was seen in mice treated with five daily doses of AmBisome (5 mg of AMB/kg . day). When the first of five daily doses of AmBisome was combined with a single low dose of Fungizone (0.1 mg of AMB/kg), the efficacy was equal to that of PEG-AMB-LIP. 相似文献
68.
69.
IA Burney 《Canadian Metallurgical Quarterly》1998,91(5):467-470
PURPOSE: Thromboprophylaxis with heparins after total joint replacement is well accepted. The aim of this prospective randomized study was to evaluate the thrombo-prophylactical efficiency of an ankle joint moving device (Artroflow) after total knee arthroplasty. METHOD: In this prospective study 160 patients were examined who had undergone total knee arthroplasty (TKA). All of the 160 patients received Enoxaparin 1 x 40 mg subcutaneously per day. In addition to this, 90 patients received Artroflow three times a day for 30 minutes. The passive movements of the ankle joint lead to an emptying of the foot and calf veins. Except for the daily routine, we performed physical examination and ultrasound in colour, compression and duplex technique one day before surgery and at the 7th and 14th day after surgery. If a thrombosis was suspected, an ascending phlebography was carried through. RESULTS: The overall thrombosis rate was 6.3% (n = 10). 11.4% (n = 70) deep vein thromboses (DVT) could be observed in the group without Artroflow. Thrombosis occurred in the group with Artroflow in 2 cases (2.2%, n = 90). A statistical difference was found between the two patient groups (p < 0.05, Chi-Square-test). One patient was excluded from the study because of pain in the ankle joint at the fourth day of treatment. CONCLUSION: In addition to heparins, this ankle joint moving device can be recommended as a physical way to prevent DVTs in the thromboprophylaxis of total knee arthroplasty. 相似文献
70.
HD Craig M Günel O Cepeda EW Johnson L Ptacek GK Steinberg CS Ogilvy MJ Berg SC Crawford RM Scott E Steichen-Gersdorf R Sabroe CT Kennedy G Mettler MJ Beis A Fryer IA Awad RP Lifton 《Canadian Metallurgical Quarterly》1998,7(12):1851-1858
Cerebral cavernous malformation (CCM) is a Mendelian model of stroke, characterized by focal abnormalities in small intracranial blood vessels leading to hemorrhage and consequent strokes and/or seizures. A significant fraction of cases is inherited as an autosomal dominant trait with incomplete penetrance. Among Hispanic Americans, virtually all CCM is attributable to a founder mutation localized to 7q ( CCM1 ). Recent analysis of non-Hispanic Caucasian kindreds, however, has excluded linkage to 7q in some, indicating at least one additional CCM locus. We now report analysis of linkage in 20 non-Hispanic Caucasian kindreds with familial CCM. In addition to linkage to CCM1, analysis of linkage demonstrates linkage to two new loci, CCM2 at 7p13-15 and CCM3 at 3q25.2-27. Multilocus analysis yields a maximum lod score of 14.11, with 40% of kindreds linked to CCM1, 20% linked to CCM2 and 40% linked to CCM3, with highly significant evidence for linkage to three loci (linkage to three loci supported with an odds ratio of 2.6 x 10(5):1 over linkage to two loci and 1.6 x 10(9):1 over linkage to one locus). Multipoint analysis among families with high posterior probabilities of linkage to each locus refines the locations of CCM2 and CCM3 to approximately 22 cM intervals. Linkage to these three loci can account for inheritance of CCM in all kindreds studied. Significant locus-specific differences in penetrance are identified. These findings have implications for genetic testing of this disorder and represent an important step toward identification of the molecular basis of this disease. 相似文献