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Zusammenfassung Es wird gezeigt, daß die Zellwände der Parenchymzellen des Apfelmesocarps (Apfelmark) — nachgewiesen an Handelsproben und eigenen Zubereitungen — dicker sind, als diejenigen der mcisten in Frage kommenden Fruchtmarkzellen. Die Zellwände solcher Speicherzellen zeigen infolge der bei direkter Durchsicht ungerichtet gelagerten Cellulosemicelle statistische optische Isotropic. Die langen Achsen der Indexellipsoide liegen in diesen Zellwänden durchweg tangential, so daß die Längsschnitte, umgebogenen Ränder and Falten der Zellwände, so wie steil verlaufende Anteile dieser am Rande der Zellen und neben Falten soweit Parallelisierung der Cellulosemicelle ergeben, daß these bevorzugten Stellen anisotrop, also doppelbrechend sind (Folienstruktur).Bei mikroskopischer Untersuchung der Fruchtmarkzellen in dünner Schicht (Einzellschicht) zwischen gekreuzten Polarisatoren mit Gipskompensator Rot I. Ordnung zeigen die Apfelmarkzellen infolge ihrer größeren Dicke lebhaftere und höhere Interferenzfarben jener bevorzugten Stellen, als alle anderen in Frage kommenden Fruchtmarkzellen. Mit Hilfe dieser optischen differentiellen Anfärbung lassen sich Apfelmarkzellen in Zubereitungen anderer Früchte mit Leichtigkeit und Sicherheit in geringsten Mengen nachweisen.  相似文献   
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The Fermentative Degradation of Potato Starch Granules. The difference between the fermentation of the starch granules as a whole in the living cells during germination of the potato tuber and the enzymatic destruction of the isolated starch granules by microorganisms (bacteria or fungi) is once more demonstrated. The last named process results by setting pores or little channels into the substance of the starch granules or following the weaker zones of the sheaths.  相似文献   
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Computer communication as an aid to independence for older adults   总被引:1,自引:0,他引:1  
Computer and communication technologies offer the potential of improving die quality of life for older people by providing them with links to information and services outside of the home. This study examined die feasibility of older people using an electronic text message system to perform routine communication tasks. In addition information was gathered to identify design parameters which facilitate the interactions of older people with such computer based systems. A specialized and simplified 'communication computer' was placed in the homes of 36 older women, aged 50-95 years. The system was provided with: a simple text-editor, basic electronic mail functions and access to news/ weather, movie reviews, and health information. Both performance data and user preference data were collected. Results indicated that the participants liked using the system, were able to use it with minimal difficulty, and that it provided a valuable means for social interaction and mental stimulation. The findings suggest that computer-based systems can be a valuable support tool for older adults if they are easy to use, and provide applications that are useful for them.  相似文献   
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Meta-analysis was used to examine pooled parameter estimates of 9 active compared with 6 control conditions of the Resources for Enhancing Alzheimer's Caregiver Health (REACH) project at 6 months on caregiver burden and depressive symptoms. Associations of caregiver characteristics and outcomes were examined. For burden, active interventions were superior to control conditions (p=.022). Also, active interventions were superior to control conditions for women versus men and for caregivers with lower education versus those with higher education. For depressive symptoms, a statistically significant association of group assignment was found for Miami's family therapy and computer technology intervention (p=.034). Also, active interventions were superior to control conditions for Hispanics, nonspouses, and caregivers with lower education. Results suggest interventions should be multicomponent and tailored. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This paper describes the development and application of a methodology for evaluating how physicians and nurses view the usefulness of various sources of patient information available within a hospital intensive care unit (ICU). The methodology encompasses semi-structured interviews, task analysis, a simulated case study of a critically ill patient, verbal protocol analysis, questionnaire responses based on both past experiences in the ICU and performance on the simulated task, and a post-task interview. Eleven nurses and six physicians participated in the study. Analysis of the questionnaires revealed significant differences in the rankings of the information sources by both the nurses and the physicians on each of seven evaluation criteria. Significant differences were also found among both the physicians and the nurses in rankings of the relative importance of the individual information sources for meeting task requirements. A framework for describing information gathering applicable to critical care environments was proposed as a means for better understanding how information sources are used. Overall, the methodology was found to be useful in terms of providing valuable data regarding the utility and usability of information sources. The importance of using a systematic approach for assessing the usefulness of information sources, particularly from the perspectives of performing design interventions and predicting the effectiveness of new information technologies, as well as the limitations in adopting this type of approach, are also discussed.  相似文献   
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To determine the significance of antibodies to single-stranded (anti-ssDNA) and double-stranded DNA (anti-dsDNA) in antinuclear antibody (ANA)-positive type 1 autoimmune hepatitis, sera from 53 patients were tested by enzyme immunosorbent assay (ELISA) and indirect immunofluorescence using the Crithidia luciliae substrate. Anti-dsDNA were detected in 18 patients (34%) by ELISA and 12 patients (23%) by the Crithidia-based assay. Twenty patients with anti-dsDNA by either assay (38%) had higher serum levels of immunoglobulin G (3971 +/- 270 mg/dL vs. 3201 +/- 247 mg/dL, P = .05) than seronegative patients. They also had human leukocyte antigen (HLA) DR4 more commonly than other patients (83% vs. 41%, P = .006) and normal subjects (83% vs. 30%, P = .00007). In contrast to patients seropositive by the Crithidia-based assay, those seropositive by ELISA failed corticosteroid therapy more commonly (24% vs. 3%, P = .04). Anti-ssDNA were found in 45 patients (85%) and they did not distinguish patients with different clinical features or outcomes. We conclude that anti-dsDNA are common in ANA-positive type 1 autoimmune hepatitis. HLA DR4 is associated with their production, and seropositivity by ELISA characterizes patients who have a poorer immediate response to corticosteroid treatment. Anti-ssDNA are common but they do not have important clinical implications.  相似文献   
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