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1.
A chapter of expository text was presented on a CRT with optional "windowing" of definitions of selected words varying in relevance to each screen's main ideas. A test treatment was interposed to influence reading strategies. Dependent variables included text reading time, frequency of definition "calls," definition reading rates, and scores on a final comprehension test. Results indicate that a technical chapter can be read from a CRT with appreciable content retention. Subjects accessed 80% of available definitions, but those able to "call" content-relevant definitions increased their frequency of definition "calls." Definition reading rate diminished; comprehension and processing time increased only for subjects accessing the theoretically relevant definitions. The results suggest how the use of definitions enhances the comprehension of on-line training manuals, texts, and help screens. "Callable" definitions need not include all low-frequency technical concepts but only those relevant to reductive main ideas.  相似文献   
2.
OBJECTIVES: This paper describes a videotaped, home-based, strength training program, titled Strong-for-Life and reports on its effectiveness in improving muscle strength, psychological well-being, and health status in a sample of older persons. DESIGN AND SETTING: We enrolled 102 nondisabled, community-dwelling older people aged 66 to 87, identified from the Medicare beneficiary list, into a randomized, controlled trial. MEASUREMENTS: Effectiveness was based on change in isokinetic upper and lower extremity muscle strength, psychologic well-being, and health status. RESULTS: Results revealed several statistically significant short-term benefits after 12 to 15 weeks of exercise, especially for men. Younger older adults demonstrated a 10% improvement in knee extensor strength relative to control subjects. Older male exercisers achieved significant differences relative to controls in perceived anger, tension, and overall social functioning. Male exercisers, in general, achieved significant improvement in perceived vigor. Women did not report psychological benefits following participation in the program. CONCLUSION: Study results reveal that the Strong for Life program, designed to be widely disseminated to the nondisabled older population, has many short-term positive benefits.  相似文献   
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4.
Objective. To assess the role of coronal and sagittal vertebral clefts in diagnosing skeletal dysplasias. Material and Methods. A search in the database at the International Skeletal Dysplasia Registry revealed 40 different diagnoses in which coronal or sagittal clefts were present, the major groups being: atelosteogenesis, chondrodysplasia punctata, dyssegmental dysplasia, Kniest dysplasia and short rib polydactyly syndrome. We reviewed all firm cases with both AP and lateral films of the spine in these major groups (n = 143), with patients' ages ranging from 20 weeks of gestation up to 26 years of age. Results. Ninety-four percent of all clefts were found in children less than 1 year of age, mainly located in the thoracolumbar region. Fifty-six percent of the clefts were observed in boys. Coronal clefts were more common than sagittal clefts. Clefts were most frequently observed in atelosteogenesis (88%), followed by chondrodysplasia punctata (79%), dyssegmental dysplasia (73%), Kniest dysplasia (63%) and short rib polydactyly syndrome (53%). Conclusion. Vertebral clefts are of major diagnostic value in the groups mentioned above, especially before 1 year of age. The search did not come up with new entities in which vertebral clefts are of major diagnostic value.  相似文献   
5.
We examined differences in subjective age identification from adolescence to old age and the relation between subjective age and fears about one's own aging and life satisfaction. Using a questionnaire format, 188 men and women from 14 to 83 years of age made judgments about how old they felt, looked, acted, and desired to be. Respondents also answered questions about their personal fears of aging and present life satisfaction. Results revealed that individuals in their teens held older subjective age identities, whereas during the early adult years, individuals maintained same age identities. Across the middle and later adult years, individuals reported younger age identities, and women experienced younger age identities than men across these adults years. Results also revealed that discrepancies between subjective and actual age were associated with personal fears of aging and life satisfaction, especially in younger men and women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Metamemory is accurate if it returns correct information about the contents in store. It is efficient if it appropriately controls search durations so that more time is allocated to seeking information actually present, and less to information actually absent. 36 adults in 3 age groups (19–22, 44–53, and 65–74 yrs) answered questions on heterogeneous topics, and their responses were timed. Next, metamemorial judgments were made for each S's set of unanswered questions. The same items were then attempted in multiple-choice format, and confidence ratings in the answers were taken. All age groups showed comparable ability to retrieve answers from memory. All showed accurate and efficient metamemory, with no age differences in either. A signal detection analysis raised the possibility that metamemorial sensitivity increases with age. The data also suggest caution among the elderly in suppressing available but low-confidence answers. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
Massive medial calcific deposits (M?nckeberg's calcinosis) are described in the peripheral and visceral arteries, and similar but small-sized deposits in the coronary arteries of a 41 year old woman with diabetes mellitus. Although observed by roentgenogram fairly commonly during life in the muscular arteries of the legs in middle-aged men, medial calcinosis infrequently involves the visceral arteries and has never, to our knowledge, been documented in the coronary arteries. Although it may be associated with intimal atherosclerosis, medial calcinosis, per se, does not obstruct the lumens of the arteries and, therefore, does not lead to symptoms or signs of limb or organ ischemia. The cause of medial calcinosis remains a mystery, but it appears to affect people with diabetes more frequently than those without.  相似文献   
8.
A. Crider, G. Schwartz, and S. Shnidman's (see 43:8) reply to E. S. Katkin and E. N. Murray's (see 42:10) review of instrumental autonomic conditioning makes several valid points but also contains many differences in interpretation based on a contrasting theoretical position. It is contended herein that the acceptability of "facts" as "facts" and "evidence" as "evidence" is determined often by predisposing epistemological orientations. Many of Crider et al.'s points are well taken, but the evidence on instrumental autonomic conditioning in humans remains far less convincing than the evidence available from animal studies. The methodological questions raised by Katkin and Murray's earlier paper appear to be clarified substantially by some of Crider et al.'s comments; however, the clarification has not reduced the danger of artifacts being interpreted as substantive evidence. (30 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
We describe a new type of scanning probe microscope based on a superconducting quantum interference device (SQUID) that resides on the apex of a sharp tip. The SQUID-on-tip is glued to a quartz tuning fork which allows scanning at a tip-sample separation of a few nm. The magnetic flux sensitivity of the SQUID is 1.8 μΦ(0)/Hz and the spatial resolution is about 200 nm, which can be further improved. This combination of high sensitivity, spatial resolution, bandwidth, and the very close proximity to the sample provides a powerful tool for study of dynamic magnetic phenomena on the nanoscale. The potential of the SQUID-on-tip microscope is demonstrated by imaging of the vortex lattice and of the local ac magnetic response in superconductors.  相似文献   
10.
Total anthocyanins (TAC) and individual anthocyanidins (AN) after hydrolysis were measured in 15 red and purple-fleshed potato cultivars produced in five different locations in the Czech Republic and a new cultivar Blaue St. Galler from Switzerland. It was found that TAC, expressed as cyanidin content, varied between 0.7 mg 100 g−1 FW (cv. Blue Congo) and 74.3 mg 100 g−1 FW (cv. Blaue Ludiano). Major differences in cultivars were found for AN relative abundance. For cv. Highland Burgundy Red a high proportion of pelargonidin (98.7%) was characteristic, whereas cv. British Columbia Blue contained almost exclusively cyanidin. Cultivars Violette and Vitelotte showed a relatively high content of malvidin. Cultivar Shetland Black differed from others with its higher content of peonidin (on average 36.7%). High petunidin abundance in the cultivars Valfi, Blue Congo, Salad Blue, Blaue St. Galler, Blaue Hindel Bank, Blaue Ludiano, Blaue Schweden, Farbe Kartoffel and Salad Red was found. TAC and AN contents highly corresponded with antioxidant activity (AA) determined with the ABTS, FRAP and DPPH assays in vitro. High AA was shown by the cultivars Vitelotte, Violette, Blaue Ludiano, Hafija, and Highland Burgundy Red. Increased height above sea level, higher annual sum of precipitation, and lower annual average temperatures caused higher AA and TAC. A high degree of hydroxylation and/or methoxylation of individual anthocyanidins could contribute in conjunction with other phenolics to high AA (peonidin, delphinidin and malvidin in the cultivars Blue Congo, Highland Burgundy Red and Shetland Black). Consequently, new red and purple-fleshed cultivars with high TAC and highly methoxylated and/or hydroxylated AN could be a promising source of favourable antioxidants in human nutrition.  相似文献   
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