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91.
We studied whether disabled older women with coronary heart disease can perform resistance training at an intensity sufficient to improve measured and self-reported physical function [n = 30, 70.6 +/- 4.5 (SD) yr]. Compared with the controls, the resistance-training group showed significant improvements in overall measured physical function score using the Continuous-Scale Physical Functional Performance Test (+24 vs. +3%). The Continuous-Scale Physical Functional Performance Test measures physical function for 15 practical activities, such as carrying groceries or climbing stairs. Resistance training led to improved measures for domains of upper body strength (+18 vs. +6%), lower body strength (+23 vs. +6%), endurance (+26 vs. +1%), balance and coordination (+29 vs. -2%), and 6-min walk (+15 vs. +7%). Women involved in the flexibility-control group showed essentially no improvement for physical function measures. No changes were observed for body composition, aerobic capacity, or self-reported physical function in either group. In conclusion, disabled older women with coronary heart disease who participate in strength training are able to train at an intensity sufficient to result in improvements in multiple domains of measured physical functional performance, despite no change in lean body mass.  相似文献   
92.
We examined patterns of territory acquisition and reconnaissance in common loons, Gavia immer, from northern Wisconsin. Among all territory acquisitions, 41.5% occurred through passive occupation of territories left vacant after the death or desertion of a previous resident, 17% constituted founding of new territories and the remaining 41.5% came about through take-over: either usurpation of defended territories or appropriation of territories before the seasonal return of previous owners. Take-overs occurred in both sexes, but individuals acted alone, never in pairs. Displaced breeders usually took refuge on undefended lakes near their former territories; about half of these loons later regained former territories through passive occupation or took possession of new territories elsewhere. As predicted by the reconnaissance hypothesis, usurpations occurred most often in territories that had produced chicks during the previous 12 months, suggesting that loons use the presence or absence of chicks as a cue for territorial usurpation. Large individuals of both sexes held onto territories longer than small individuals, an indication that body size might be correlated with fighting ability. In terms of life history, loons appear to locate good territories through reconnaissance, usurp them in a subsequent year and recover from displacements by reclaiming their original territories or new ones. Copyright 2000 The Association for the Study of Animal Behaviour.  相似文献   
93.
Transplantable tumors and cell lines have been developed from pheochromocytomas arising in mice with a heterozygous knockout mutation of the neurofibromatosis gene, Nf1. Nf1 encodes a ras-GTPase-activating protein, neurofibromin, and mouse pheochromocytoma (MPC) cells in primary cultures typically show extensive spontaneous neuronal differentiation that may result from the loss of the remaining wild-type allele and defective regulation of ras signaling. However, all MPC cell lines express neurofibromin, suggesting that preservation of the wild-type allele may be required to permit the propagation of MPC cells in vitro. MPC lines differ from PC12 cells in that they express both endogenous phenylethanolamine N-methyltransferase (PNMT) and full-length PNMT reporter constructs. PNMT expression is increased by dexamethasone and by cell-cell contact in suspension cultures. Mouse pheochromocytomas are a new tool for studying genes and signaling pathways that regulate cell growth and differentiation in adrenal medullary neoplasms and are a unique model for studying the regulation of PNMT expression.  相似文献   
94.
The application of Chiral Technology, or the (extensive) use of techniques or tools for the determination of absolute stereochemistry and the enantiomeric or chiral separation of racemic small molecule potential lead compounds, has been critical to successfully discovering and developing chiral drugs in the pharmaceutical industry. This has been due to the rapid increase over the past 10-15 years in potential drug candidates containing one or more asymmetric centers. Based on the experiences of one pharmaceutical company, a summary of the establishment of a Chiral Technology toolbox, including the implementation of known tools as well as the design, development, and implementation of new Chiral Technology tools, is provided.  相似文献   
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96.
Ohne Zusammenfassung  相似文献   
97.
The incidence and etiology of carotenemia in mentally retarded children were examined. Fasting serum carotenoid and vitamin A levels were measured in 77 profoundly mentally retarded children aged 3 to 19 years who were receiving a standard diet containing 2000 IU of carotene (expressed in terms of vitamin A activity) and supplemented by 2000 IU of vitamin A daily. Seventeen of the 77 patients had serum carotenoid levels of more than 300 μg./ml. The particulate size of food had a significant inverse relationship to serum carotenoid levels and was an important factor in determining carotenemia. The serum vitamin A level was also higher in children on homogenized diet than in those on pureed feeds, while the lowest level was noted among patients on a chopped diet. Besides particulate size of food, other factors may also be operative in determining carotenemia.  相似文献   
98.
Berichtigung     
Ohne Zusammenfassung  相似文献   
99.
100.
Parkinson's disease is a neurodegenerative disorder manifesting in debilitating motor symptoms. This disorder is characterized by abnormal activity throughout the cortico-basal ganglia loop at both the single neuron and network levels. Previous neurophysiological studies have suggested that the encoding of movement in the parkinsonian state involves correlated activity and synchronized firing patterns. In this study, we used multi-electrode recordings to directly explore the activity of neurons from the globus pallidus of parkinsonian primates during passive limb movements and to determine the extent to which they interact and synchronize. The vast majority (80/103) of the recorded pallidal neurons responded to periodic flexion-extension movements of the elbow. The response pattern was sinusoidal-like and the timing of the peak response of the neurons was uniformly distributed around the movement cycle. The interaction between the neuronal activities was analyzed for 123 simultaneously recorded pairs of neurons. Movement-based signal correlation values were diverse and their mean was not significantly different from zero, demonstrating that the neurons were not activated synchronously in response to movement. Additionally, the difference in the peak responses phase of pairs of neurons was uniformly distributed, showing their independent firing relative to the movement cycle. Our results indicate that despite the widely distributed activity in the globus pallidus of the parkinsonian primate, movement encoding is dispersed and independent rather than correlated and synchronized, thus contradicting current views that posit synchronous activation during Parkinson's disease.  相似文献   
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