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SC Bowden B Dodds G Whelan C Long P Dudgeon A Ritter C Clifford 《Canadian Metallurgical Quarterly》1997,19(5):755-762
Previous analyses of the Wechsler Memory Scale-Revised (WMS-R; Wechsler, 1987) have reported one-, two-, and three-factor solutions and raised questions about the validity of the visual memory subtests. These various findings may stem in part from different methods of analysis, and from the study of different participant samples. To address these issues, we analysed data from the WMS-R and a spatial maze test administered to 154 participants with a history of alcohol dependence. Results from confirmatory factor analysis supported the interpretation of three factors underlying the WMS-R subtests and the spatial maze score in this sample, namely, attention-concentration, immediate memory, and delayed recall. This result held despite the inclusion of the maze score which is a well-validated measure of visuo-spatial memory. 相似文献
3.
Substrate specificity of the Escherichia coli RuvC protein. Resolution of three- and four-stranded recombination intermediates 总被引:3,自引:0,他引:3
The specificity of the Escherichia coli RuvC Holliday junction resolvase has been investigated in vitro. RuvC protein cleaves synthetic DNA substrates that model three- or four-stranded recombination intermediates but fails to act upon Y junctions, G/A mismatches, heterologous loop structures, or two-stranded branched junctions. RuvC therefore differs from endonuclease VII of bacteriophage T4 which exhibits broad range specificity. Using related three- and four-stranded synthetic DNA junctions, we show that RuvC cleaves both junctions at the same DNA sequence and requires a region of homology at the junction point. The action of RuvC on three- and four-stranded recombination intermediates made by RecA was also investigated. We found that RuvC fails to resolve three-stranded intermediates in the presence of RecA, although four-stranded intermediates are resolved under the same conditions. However, both three- and four-stranded intermediates are substrates for the nuclease after removal of RecA. We interpret these differences in terms of the contiguity of the RecA nucleoprotein filament which may, under certain conditions, limit access to the Holliday junction resolvase. 相似文献
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SC Froehner 《Canadian Metallurgical Quarterly》1998,282(5392):1277-1279
6.
Analysis of the S-phase fractions (SPF) measured by in vitro thymidine labeling, morphological appearances, and estrogen receptor (ER) assays of primary invasive breast carcinomas demonstrated several interrelationships. Lobular, mucinous, tubular, and adenocystic carcinomas consistently had low SPF and were usually positive for ER. The same was true for the carcinomas of no special histologic type [the not otherwise specified (NOS) group of E. R. Fisher including "infiltrating ductal" and undifferentiated carcinomas] with minimal anaplasia. Medullary, atypical medullary, and morphologically unclassifiable carcinomas with marked nuclear anaplasia nearly always had high SPF and were usually negative for ER. High SPF was associated with advanced stages of carcinoma initially or with early recurrence following mastectomy. 相似文献
7.
Intravenous glucose tolerance test in middle-aged men with and without latent coronary heart disease
During a cardiovascular survey, aimed at detecting cases of latent coronary heart disease (CHD), glucose elimination was studied after i.v. loading in 1970 presumably healthy men aged 40-59 years. The aim was to throw light on the importance of deranged glucose tolerance for the development of CHD. Of the 1970 individuals, 1798 were defined as "normals", 33 had chronic, non-anginal chest pain, 34 had slight albeit typical angina pectoris. The remaining 105 had various symptoms/signs strongly suggestive of CHD, and underwent diagnostic coronary angiography (69 angiopositive, 36 angionegative). Plasma insulin was determined in relation to the test in 249 of the subjects. The following conclusions were reached: 1) Mean k-values were similar in all subgroups (p less than 0.10). 2) Low and borderline k-values were significantly more frequent in angiographed individuals compared with the group of normals (p less than 0.025). However, an almost identical frequency was seen in angiopositive and angionegative cases. 3) K-values did not change with age between 40 and 59 years. 4) K-values were unrelated to the severity of angiographic findings in individuals with proven CHD. 5) Significantly lower k-values were found in individuals with a positive diabetic heredity, and 6) in individuals with a high insulin response. 7) The i.v. glucose loading did not influence an exercise ECG recorded in relation to a near-maximal bicycle exercise test. 相似文献
8.
Myocardial biopsies from two patients who had developed "stone heart" (myocardial rigor mortis; ischemic contracture of the left ventricle) were studied by electron microscopy. The ultrastructure of tissue in stone heart, though ischemic in nature, differed from that of classic myocardial infarction in some respects. Apart from depletion of glycogen and distension of the sarcoplasmic reticulum and T-tubules, myofibrillar degeneration was much more widespread. Mitochondrial degeneration with active lysosomal autodigestion, disruption of the microcirculation, and lymphedema were prominent changes also observed. In the light of known clinical and experimental observations, our findings suggest that stone heart is an accelerated form of ischemic injury occurring in vulnerable (hypertrophied) hearts and is probably related to ischemia-triggered release of endogenous catecholamines. 相似文献
9.
We investigated which program characteristics in children's entertainment television programs children between 6 and 11 years of age value. We collected data by means of questionnaires among 100 Dutch and 100 U.S. first through fourth graders. The most important characteristics for both Dutch and U.S. children were comprehensibility and action, closely followed by humor, interestingness, innocuousness, realism, violence, and romance, respectively. Compared to Dutch children, U.S. children attached more value to realism, innocuousness, and interestingness. Boys in both samples attached more value to action and violence in a children's program, whereas girls in both samples attached more value to innocuousness and comprehensibility. 相似文献
10.
PN Amess J Baudin J Townsend J Meek SC Roth BG Neville JS Wyatt A Stewart 《Canadian Metallurgical Quarterly》1998,40(11):724-730
Osteoporotic fractures, and in particular, hip fractures result in significant morbidity and mortality. Low bone mass is the main risk factor of enhanced bone fragility, resulting in an increased risk for hip fracture. Bone density of osteoporotic women with and without hip fractures show a considerable overlap. Therefore, other bone-independent factors also play an important role for the development of hip- and other osteoporotic fractures. One other important factor is falling. In 90% of hip fractures falling was involved [10-15], but only 5% or less of these falls resulted in a subsequent fracture. The view that adequate exercise is beneficial for skeletal health of children and for prevention and treatment of osteoporosis in adults is supported primarily by two lines of evidence: longitudinal and cross-sectional trials in children and young adult athletes showing a significant increase of muscle- and bone mass after strenuous (children) or chronic exercise (athletes) as compared to normally active (children) or sedentary control subjects. What are the potential benefits and limits of specific exercise programs with respect to bone mass, prevention of falls and fractures? In this review these questions are discussed and a specific exercise program in osteoporotic patients with fractures is delineated. 相似文献