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Significant amounts of β-glucan solubilase activity have been found in barleys harvested from a number of test sites. Enzyme activity appeared to be related to the climatic conditions at crop maturity, indicating that β-glucan solubilase was generated, possibly, by microflora on the barley grain. Species of the most common field fungi genera, Alternaria, Cladosporium, Epicoccum and Helminthosporium and two bacterial cultures were isolated from barley kernels and incubated on autoclaved barley for solubilase examinations. All the fungal isolates studied showed abilities to reduce the viscosity of carboxymethyl cellulose and to solubilise barley β-glucan. The molecular size distribution of the solubilised β-glucan products resembled that obtained for products formed by a partially purified preparation of solubilase from barley. It has been concluded, therefore, that the common field fungi associated with the hull and seed cot of barley may be the source of β-glucan solubilase. 相似文献
155.
Efficacy of high-dose glycine in the treatment of enduring negative symptoms of schizophrenia 总被引:1,自引:0,他引:1
U Heresco-Levy DC Javitt M Ermilov C Mordel G Silipo M Lichtenstein 《Canadian Metallurgical Quarterly》1999,56(1):29-36
PURPOSE: To assess the effectiveness and safety of self-expanding metallic stents as a primary palliative treatment for inoperable malignant colorectal strictures. METHODS: Under radiological guidance 20 self-expanding metallic Wallstents were implanted in 16 consecutive patients with colorectal stenoses caused by malignant neoplasms, when surgical treatment of the condition had been ruled out. The patients were followed up clinically for 1-44 months, until death or termination of this study. RESULTS: The stents were successfully implanted in all cases and resolved the clinical obstruction in all the patients except one, who underwent subsequent colostomy. During follow-up of the remaining 15 patients, clinical complications arising from the procedure were pain (two patients), minor rectal bleeding (one patient), and severe rectal bleeding (one patient) (26%). There were three cases of stent migration and three cases of stent occlusion, and reintervention by us was necessary in 20% of cases (3/15). The mean life span following the procedure was 130 days, and none of the patients exhibited clinical symptoms of obstruction at the time of death (12 patients) or termination of the study (3 patients). CONCLUSION: Deployment of metallic stents under radiologic guidance is an effective alternative as a primary palliative measure in malignant colorectal obstruction, though the possible clinical complications and need for repeat intervention during follow-up should be taken into account. 相似文献
156.
DC Gooding 《Canadian Metallurgical Quarterly》1999,35(2):157-166
Individuals who scored high on Perceptual Aberration-Magical Ideation Scales (Per-Mag; n = 90), the Social Anhedonia Scale (SocAnh; n = 39), and control participants (n = 89) were administered saccadic refixation (prosaccade) and saccadic suppression (antisaccade) tasks. Eye movements were scored in terms of error rates and latency. None of the groups differed in terms of their performance on the prosaccade task. Both the Per-Mag (p < 0.01) and SocAnh (p < 0.05) groups exceeded the controls in terms of mean antisaccade errors. The high-risk groups did not differ from each other. Eighteen of the Per-Mag individuals and 10 of the SocAnh individuals displayed deviant antisaccade performance. These findings are particularly interesting in light of suggestive evidence that antisaccade task deficits may serve as a marker of susceptibility to schizophrenia. It is hypothesized that the individuals who scored aberrantly on the Chapman scales and displayed antisaccade performance deficits are most likely to be at risk for the development of psychosis. 相似文献
157.
Davidson Karina; MacGregor Michael Wm.; Stuhr Judith; Dixon Kim; MacLean David 《Canadian Metallurgical Quarterly》2000,19(1):55
The creation of an observational Constructive Anger Behavior—Verbal Style Scale (CAB-V) and its relation to resting blood pressure (BP) in an age- and sex-stratified, population-based sample is examined. Participants (N?=?1,862) provided hypertension risk factor information, had resting BP assessed multiple times, and completed a videotaped interview, which was later coded for CAB-V and Hostile Style. High CAB-V scores remained a significant predictor of lower resting BP when controlling for the effects of standard hypertension risk factors (age, sex, body mass index, physical activity, alcohol use, smoking status, parental myocardial infarction history, education, and diabetic status) and psychosocial measures (anxiety, depression, hostility, social support, and Hostile Style). This relation also remained when excluding known hypertensive persons. Results suggest that constructive anger expression may have an independent beneficial association with resting BP. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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DC Hodgins SY Kang L deArriba V Parre?o LA Ward L Yuan T To LJ Saif 《Canadian Metallurgical Quarterly》1999,73(1):186-197
Although maternal antibodies can protect against infectious disease in infancy, they can also suppress active immune responses. The effects of circulating maternal antibodies, with and without colostrum and milk antibodies, on passive protection and active immunity to human rotavirus (HRV) were examined in gnotobiotic pigs. Pigs received intraperitoneal injections of high-titer serum (immune pigs [groups 1 and 2]) from immunized sows, low-titer serum from naturally infected sows (control pigs [groups 3 and 4]), or no serum (group 5). Immune or control colostrum and milk were added to the diet of groups 2 and 4, respectively. After inoculation (3 to 5 days of age) and challenge (postinoculation day [PID] 21) with virulent HRV, the effects of maternal antibodies on protection (from diarrhea and virus shedding), and on active antibody responses (measured by quantitation of antibody-secreting cells [ASC] in intestinal and systemic lymphoid tissues by ELISPOT) were evaluated. Groups 1 and 2 had significantly less diarrhea and virus shedding after inoculation but higher rates of diarrhea and virus shedding after challenge than did groups 3 and 5. Group 1 and 2 pigs had significantly fewer immunoglobulin A (IgA) ASC in intestinal tissues at PID 21 and at postchallenge day (PCD) 7 compared to group 5. Significantly fewer IgG ASC were present in the intestines of group 2 pigs at PID 21 and PCD 7 compared to group 5. There was a trend towards fewer ASC in intestinal tissues of group 2 than group 1, from PID 21 on, with significantly fewer IgA ASC at PCD 7. IgG ASC in the duodenum and mesenteric lymph nodes of group 3 and 4 pigs were significantly fewer than in group 5 at PCD 7. These decreases in ASC emphasize the role of passive antibodies in impairing induction of ASC rather than in merely suppressing the function of differentiated B cells. To be successful, vaccines intended for populations with high titers of maternal antibodies (infants in developing countries) may require higher titers of virus, multiple doses, or improved delivery systems, such as the use of microencapsulation or immune stimulating complexes, to overcome the suppressive effects of maternal antibodies. 相似文献
160.
MacGregor James N.; Ormerod Thomas C.; Chronicle Edward P. 《Canadian Metallurgical Quarterly》2001,27(1):176
The 9-dot problem is widely regarded as a difficult insight problem. The authors present a detailed information-processing model to explain its difficulty, based on maximization and progress-monitoring heuristics with lookahead. In Experiments 1 and 2, the model predicted performance for the 9-dot and related problems. Experiment 3 supported an extension of the model that accounts for insightful moves. Experiments 4 and 5 provided a critical test of model predictions versus those of previous accounts. On the basis of these findings, the authors claim that insight problem solving can be modeled within a means–ends analysis framework. Maximization and progress-monitoring heuristics are the source of problem difficulty, but also create the conditions necessary for insightful moves to be sought. Furthermore, they promote the discovery and retention of promising states that meet the progress-monitoring criterion and attenuate the problem space. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献