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991.
Comments on R. J. Sternberg and T. I. Lubart's article (see record 83-30546) on the neglect and problems of creativity as a research topic. The original authors suggested a confluence approach to the study of creativity, encompassing contributions both within and without psychology. Schneider agrees with this suggestion, but argues that its success depends on finding and connecting all pertinent links concerning creativity. The integration of a broad range of research with the study of creativity seems likely to increase the chance of progress in understanding and perhaps "teaching" creativity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
Sphingolipid activator proteins SAP-A, -B, -C and -D (also called saposins) are generated by proteolytic processing from a 73 kDa precursor and function as obligatory activators of lysosomal enzymes involved in glycosphingolipid metabolism. Although the SAP precursor can be recognized by the mannose-6-phosphate (M-6-P) receptor and shuttled directly from the secretory pathway to the lysosome, a substantial fraction of newly synthesized precursor is secreted from the cell where it may participate in sphingolipid transport and signaling events. Re-uptake of the secreted precursor is mediated by high-affinity cell surface receptors that are apparently distinct from the M-6-P receptor. We found that the low density lipoprotein receptor-related protein (LRP), a multifunctional endocytic receptor that is expressed on most cells, can mediate cellular uptake and lysosomal delivery of SAP precursor. Additional in vivo experiments in mice revealed that the mannose receptor system on macrophages also participates in precursor internalization. We conclude that SAP precursor gains entry into cells by at least three independent receptor mechanisms including the M-6-P receptor, the mannose receptor and LRP.  相似文献   
993.
994.
Stretching     
BACKGROUND: It has recently been reported that total daily energy expenditure (TDE) is increased in patients with chronic obstructive pulmonary disease (COPD) and it was hypothesised that these patients may have a decreased mechanical efficiency during activities. The purpose of the present study was to measure the mechanical efficiency of submaximal leg exercise, and to characterise patients with a potentially low efficiency in terms of body composition, resting energy expenditure, lung function, and symptom limited exercise performance. METHODS: Metabolic and ventilatory variables were measured breath by breath during submaximal cycle ergometry exercise performed at 50% of symptom limited achieved maximal load in 33 clinically stable patients with COPD (23 men) with forced expiratory volume in one second (FEV1) of 40 (12)% predicted. Net mechanical efficiency was calculated adjusting for resting energy expenditure (REE). RESULTS: Median mechanical efficiency was 15.5% and ranged from 8.5% to 22.7%. Patients with an extremely low mechanical efficiency (< 17%, n = 21) demonstrated an increased VO2/VE compared with those with a normal efficiency (median difference 4.7 ml/l, p = 0.005) during submaximal exercise. There was no difference between the groups differentiated by mechanical efficiency in blood gas tensions at rest, airflow obstruction, respiratory muscle strength, hyperinflation at rest, resting energy expenditure or body composition. There was a significant difference in total airways resistance (92% predicted, p = 0.03) between the groups differentiated by mechanical efficiency. CONCLUSIONS: It is concluded that many patients with severe COPD have decreased mechanical efficiency. Furthermore, based on the results of this study it is hypothesised that an increased oxygen cost of breathing during exercise contributes to the decreased mechanical efficiency.  相似文献   
995.
Glial cells produce myelin and contribute to axonal morphology in the nervous system. Two myelin membrane proteolipids, PLP and DM20, were shown to be essential for the integrity of myelinated axons. In the absence of PLP-DM20, mice assembled compact myelin sheaths but subsequently developed widespread axonal swellings and degeneration, associated predominantly with small-caliber nerve fibers. Similar swellings were absent in dysmyelinated shiverer mice, which lack myelin basic protein (MBP), but recurred in MBP*PLP double mutants. Thus, fiber degeneration, which was probably secondary to impaired axonal transport, could indicate that myelinated axons require local oligodendroglial support.  相似文献   
996.
J. W. Hall (see record 1992-30089-001) proposed that participants in spacing-effect experiments use massed repetitions as an opportunity to study previously presented items. He provided apparent evidence for this displaced-rehearsal strategy in a free-recall experiment involving unmixed lists consisting of all massed or all spaced repetitions. He argued that this strategy produces artifactual spacing effects when experiments involve mixed lists containing both massed and spaced repetitions. This raises the specter that much of the spaced-repetition literature might be contaminated by artifactual results because most experiments have used mixed-list designs. The authors replicated Hall's experiment and extended it by including critical control conditions. Although Hall's results are replicable, they are primarily attributable to factors that were uncontrolled in his study. There seems to be no compelling reason to question spacing effects obtained with mixed-list designs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
James F. T. Bugental died peacefully at age 92 at his Petaluma, California, home on September 18, 2008. Jim was a leading psychotherapist and a founding father, with Abraham Maslow and others, of humanistic psychology, or the "third force" (in contrast to psychoanalysis and behaviorism). Jim was also the creator, along with Rollo May, of existential-humanistic psychotherapy. Jim was born in Fort Wayne, Indiana, on Christmas Day in 1915. Jim earned his doctorate in 1948 from Ohio State University, where he was influenced by Victor Raimy and George Kelly. After a brief time on the University of California, Los Angeles (UCLA) faculty in psychology, Jim resigned in 1953 to found the first group practice of psychotherapy, Psychological Service Associates, with Alvin Lasko. With Abraham Maslow and others, Jim was a cofounder of the Journal of Humanistic Psychology (JHP) and the Association for Humanistic Psychology in 1961. Jim also wrote many books on the topic of psychotherapy during his lifetime. Jim was a great and bold spirit--his many writings and teachings are cherished today widely, and the field of psychology is much richer for his efforts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
998.
Switch costs in task switching are commonly attributed to an executive control process of task-set reconfiguration, particularly in studies involving the explicit task-cuing procedure. The authors propose an alternative account of explicitly cued performance that is based on 2 mechanisms: priming of cue encoding from residual activation of cues in short-term memory and compound cue retrieval of responses from long-term memory. Their short-term priming account explains the repeated cue encoding benefit, switch cost, reduction in switch cost with preparation time, and other effects. The authors develop a mathematical model of their priming account and fit it to data from 3 experiments, demonstrating that a set of basic psychological processes can produce several effects--including putative switch costs--without switching tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
999.
Abecarnil (isopropyl-6-benzyloxy-4-methoxymethyl-beta-carboline-3-carboxylate) is a metabolically stable anxiolytic and anticonvulsant beta-carboline derivative with few sedative and muscle relaxant effects in rodents. Abecamil binds with high affinity to benzodiazepine receptors. Because long-term treatment with benzodiazepines leads to development of dependence, we evaluated in mice whether abecarnil also possesses a potential for producing dependence, using electroencephalographic and electromyographic monitoring, and behavioral assessment of anxiety to detect withdrawal responses after chronic treatment. Diazepam was used as a reference. Mice withdrawn from chronic treatment with diazepam (15 mg/kg/day for 12 days) showed a time-related evolution of anxiety, muscle rigidity and seizures between days 4 and 21 after discontinuation of the treatment. A period between withdrawal days 1 and 3 was symptom free. Mice withdrawn from chronic administration of abecarnil (6 mg/kg/day for 12 days) showed no anxiety and no changes in seizure susceptibility and muscle tone. The doses of diazepam and abecarnil used for chronic treatment were equivalent in terms of kinetics and binding to benzodiazepine receptors. These data indicate that long-term treatment with abecarnil does not induce benzodiazepine-like dependence in mice. Thus, it may be predicted that chronic treatment with abecarnil in humans may offer an important alternative to benzodiazepines in the treatment of anxiety.  相似文献   
1000.
We reported a case of successful treatment of bilateral pulmonary metastasis from rectal cancer with high-dose 5'-DFUR plus MMC combination chemotherapy. A woman born in 1948 showed a recurrence in the bilateral lung about 29 months after low anterior resection. High-dose 5'-DFUR plus MMC combination chemotherapy was started in March, 1991. The chest X-ray examination 8 weeks after beginning this therapy showed a remarkable decrease in the size of the pulmonary metastatic foci and CEA decreased in the same way. The dose of 5'-DFUR was reduced after 5 courses, and then CEA increased. No remarkable side effect was encountered and the patient could be safely treated at an outpatient clinic. During this therapy no recurrence has been detected, and we performed a resection of the bilateral pulmonary metastasis by median sternotomy in October, 1991. The above findings suggested that this was an effective and safe therapy for pulmonary metastasis from colon cancers and could be a neo-adjuvant chemotherapy for surgical resection of pulmonary metastasis.  相似文献   
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