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201.
We report on the performance of a recently introduced commercial chessboard method using 12 antisera, in comparison with that of the 55-antiserum panel used in determining the serogroups and types (SGTs) of Streptococcus pneumoniae, both of which were carried out by a coagglutination technique. Of a total of 150 strains of S. pneumoniae studied, 135 (90%) belonged to the SGTs represented in the 23-valent pneumococcal vaccine; of these, 130 (96.3%) were identified as the same SGTs by both typing methods. The remaining five strains showed cross-reactivity with more than two pools by the chessboard method, but could be assigned to a single SGT by the Quellung test. The 96.3% concordance of the chessboard method suggests it can be adopted for determination of the SGTs of S. pneumoniae in laboratories. 相似文献
202.
MC Bushman 《Canadian Metallurgical Quarterly》1999,9(1):35-37
Thirty-six patients with tinea unguium were treated with 200 mg of itraconazole daily for 7 days each month. We suggested that a patient who had a lesion in the thumbnail needed 5 months of treatment for mycologial cure, while in a patient without thumbnail lesion, 3 months of treatment was enough. 相似文献
203.
We have overexpressed and purified human dual-specificity phosphatase cdc25C from a prokaryotic expression system at high levels and in a soluble, active form, and have studied and quantified its potential to interact with cdks, cyclins and preformed cdk-cyclin complexes by fluorescence spectroscopy and size-exclusion chromatography. Our data indicate that human cdc25C forms stable complexes, through hydrophobic contacts, with cdk and cyclin monomers, as well as with preformed cdk-cyclin complexes. In vitro, cdc25C interacts with cyclin monomers with high affinity, with tenfold less affinity with cdks, and with intermediate affinity with cdk-cyclin complexes. Moreover, changes observed in the intrinsic fluorescence of cdks, cyclins and cdk-cyclin complexes upon interaction with cdc25C are indicative of concomitant conformational changes within cdks and cyclins. From our results, we propose that in vitro, in the presence of monomeric cdks and cyclins, cdc25C forms stable ternary complexes, first through a high affinity interaction with a cyclin, which may then help target cdc25C towards a cdk. We discuss the biological relevance of our results and propose that a similar, two-step mechanism of interaction between cdc25C and cdk-cyclin complexes may occur in vivo. 相似文献
204.
作为全球首款支持HDMI 1.3a标准和可输出高清音频源码的声卡,华硕XOnar HDAV 1.3 Deluxef以下简称HDAV 1.3)自今年6月份在CeBIT展会上展示了工程样品以来就倍受全球高清玩家的关注。时隔3个多月,《微型计算机》高清实验室获得了这款产品,并抢先进行了测试。它能否让众多PC高清玩家获得完整的高清影音享受?这篇耗费近20天时间才完成的深度测试报告将说明一切! 相似文献
205.
HW Yoon MC Kim PG Shin JS Kim CY Kim SY Lee I Hwang JD Bahk JC Hong C Han MJ Cho 《Canadian Metallurgical Quarterly》1997,255(4):359-371
Two soybean cDNA clones, SPK-3 and SPK-4, encoding putative protein kinases were isolated and characterized. Both cDNAs encoded approximately 40-kDa serine/threonine kinases with unusual stretches of acidic amino acids in their carboxy-terminal regions, which are highly homologous to PKABA1 from wheat and ASKs from Arabidopsis. These kinases are encoded by one- or two-copy genes in the soybean genome. Notably, SPK-3 and -4 showed different patterns of expression in various soybean tissues. SPK-3 is highly expressed in dividing and elongating tissues of young seedlings but relatively weakly in tissues of mature plants. In contrast, SPK-4 showed relatively high and constitutive expression in all the tissues examined except for leaf tissues of mature plants. Although various stressors, such as dehydration and high salinity, increased the expression of both genes, the induction kinetics were different. The two genes also differed in their response to abscisic acid (ABA). SPK-3 was induced but SPK-4 was not affected by exogenously supplied abscisic acid. In accordance with these expression data analysis of the activity of a chimeric SPK-3 promoter::beta-glucuronidase (GUS) reporter gene by transient expression in tobacco leaves confirmed the inducibility of SPK-3 by salt and ABA. Polyclonal antibodies raised against a recombinant SPK-4 protein produced in Escherichia coli specifically recognized both recombinant SPK-3 and -4 proteins. Kinase assays using affinity-purified SPK-4/ antibody complexes with crude soybean extracts as substrate identified specific phosphorylation of two 41 and 170 kDa soybean proteins that were phosphorylated on serine residues. Taken together, our results suggest that SPK-3, and/or SPK-4 are functional serine protein kinase(s). Furthermore, SPK-3 and -4 may play different roles in the transduction of various environmental stresses. 相似文献
206.
SJ Lee KM Kuntz MM Horowitz PB McGlave JM Goldman KA Sobocinski J Hegland C Kollman SK Parsons MC Weinstein JC Weeks JH Antin 《Canadian Metallurgical Quarterly》1997,127(12):1080-1088
BACKGROUND: Chronic myelogenous leukemia (CML) is an indolent but ultimately fatal disease. Because the natural history of CML varies and quality of life with CML may be excellent until shortly before death, deciding whether and when to pursue unrelated donor bone marrow transplantation is often difficult. OBJECTIVE: To compare early transplantation, delayed transplantation, and no transplantation for patients with chronic-phase CML on the basis of discounted, quality-adjusted life expectancy. DESIGN: A markov model comparing different strategies was constructed. This model considers patient age, quality of life, risk aversion, and the competing risks for CML progression and transplant toxicity. SETTING: Therapeutic decision at the time of diagnosis of CML. PATIENTS: The base case is a 35-year-old patient with intermediate-prognosis CML. Younger and older patients with better and worse prognoses are also evaluated. INTERVENTION: Early transplantation, delayed transplantation, and no transplantation. MEASUREMENTS: Quality-adjusted, discounted life expectancy. RESULTS: For patients with newly diagnosed CML, transplantation within the first year provides the greatest quality-adjusted expected survival, although this benefit decreases with increasing patient age. For a 35-year-old patient with intermediate-prognosis CML, transplantation within the first year results in 53 more discounted, quality-adjusted years of life expectancy than does no transplantation. This finding is robust even with varying baseline assumptions. CONCLUSIONS: These results support the use of early unrelated donor bone marrow transplantation for most patients with CML. 相似文献
207.
AE Christian MP Haynes MC Phillips GH Rothblat 《Canadian Metallurgical Quarterly》1997,38(11):2264-2272
Previous studies from this laboratory have demonstrated that exposure of tissue culture cells to cyclodextrins results in rapid cholesterol depletion. In the present study, we have developed experimental systems for using solutions of cyclodextrins, either 2-hydroxypropyl beta-cyclodextrin or methylated beta-cyclodextrin, complexed with varying amounts of free cholesterol to manipulate cell cholesterol content. Cholesterol delivered via the cyclodextrin has been found to be metabolically active, as measured by the acyl-coenzyme A:cholesterol acyltransferase (ACAT)-mediated esterification of [3H]cholesterol in Fu5AH rat hepatoma cells and Chinese hamster ovary cells. The methylated beta-cyclodextrin was found to be a more efficient donor in all cell types studied, with an average cholesterol uptake of at least 100 microg cholesterol/mg protein within 6 h. By modifying the cyclodextrin:cholesterol molar ratio, it is possible to manipulate the cellular cholesterol content of cells, producing conditions ranging from net cholesterol enrichment to depletion. The use of cyclodextrins provides a convenient, precise and reproducible method for modulating the cholesterol content of tissue culture cells. 相似文献
208.
209.
SE Hiscox MB Hallett MC Puntis T Nakamura WG Jiang 《Canadian Metallurgical Quarterly》1997,15(6):513-521
To characterize the clinical features of childhood tuberculosis, we analyzed the symptoms, signs, and laboratory findings of the 89 children with tuberculosis admitted to the Yokohama City University Hospital from 1975 to 1994. Compared with the numbers of patients admitted from 1975 to 1979, those of patients of the past 5 years (from 1990 to 1994) were reduced by half. Of the 89 subjects, 56.2% were below 3 years of age and 24.7% were under 1 year of age. 51.7% had primary complex and 20.2% had serious tuberculosis (tuberculous meningitis 14.6%, miliary tuberculosis 3.4%, and bone and joint tuberculosis 2.2%). Tuberculous children below 3 years of age consisted of primary complex (60.0%) and serious tuberculosis (32.0%). The majority (86.0%) of tuberculous children below 3 years of age had not received BCG vaccination. In 55 (61.8%) of 89 subjects, the sources of tuberculosis were clarified. Of these subjects, 83.6% were infected in the family. The rate of BCG inocluation tended to decrease with decreasing age, especially that of children below 3 years of age was 14.0%. Of the 89 subjects, only 16.9% proved to be smear-positive. Taken together, in order to eliminate tuberculous children below 3 years of age, the following is necessary; (1) BCG inoculation in early infancy, (2) early diagnosis of index cases with adult tuberculosis, and (3) prompt and appropriate family contact examination. 相似文献
210.