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181.
Arts medicine has come of age, resulting from 3 important developments over the past decade: improved methods of diagnosis and treatment, an awareness that artists suffer from special problems related to their occupation and lifestyle, and the establishment of health programs emphasizing an interdisciplinary approach to these patients. We focus on the patterns of illness afflicting performing artists, specifically dancers, singers, actors, and instrumental musicians, and explain some of the things a health care team can do in treating these patients. The conditions governing these patients'' lives--early exposure to high expectations of excellence, incessant demands for perfection, long periods of intense practicing, fierce competition, high levels of anxiety associated with performance, and uncertain careers--need to be understood. Levels of disease and disability are remarkably high, but artists often ignore symptoms. We discuss the musculoskeletal, neurologic, vocal, psychological, and other syndromes found among performers and some of the difficulties in treating them. The prevention of injury, conservative management, collaboration with teachers, and a psychotherapeutic approach are desirable. Arts medicine programs for professional consultation exist in several major cities of the United States and abroad. Although research is needed regarding the effectiveness of health care services for performing artists, the scientific literature devoted to this field is growing.  相似文献   
182.
Methylated lysine, arginine and histidine residues are found in a number of proteins (for example, histones, non-histone chromosomal proteins, ribosomal proteins, calmodulin, cytochrome C, etc.). We are studying the effects of methylation on the conformations of poly(lysine) and of the effects of methylation of poly(lysine) and poly(arginine) on interactions with polynucleotides. The conformational properties of epsilon-amino-methylated poly(lysine) differ from those of unmodified poly(lysine). Methylation increases resistance to thermally-induced and NaCl-induced changes in the CD spectrum. Guanidinium chloride increases (proportional to the degree of methylation) the extent of approach to the conformation in dispute as to its being a random coil or an extended helix. Methylation enhances aggregation in the helix-inducing solvent 0.5 M Ca(ClO4)2. With increasing methylation of poly(lysine), the conformation in dodecyl sulfate changes from beta, to 50% alpha, to random coil at the maximum methylation. Increasing methylation of poly(lysine) weakens the interaction with polynucleotides in respect to dissociation by salt, linearly with methyl content. Complexes of (dAdT)n.(dAdT)n with the polypeptides are increasingly stabilized to heat denaturation by progressive methylation. However, with a series of synthetic double-stranded RNA's and DNA's a more complex situation exists, Tm increasing or decreasing, depending on the base composition, sequence and type of sugar. Methylation of poly(lysine) and poly(arginine) can have opposite effects on Tm based on results with complexes with (dI)n.(dC)n. Methylated poly(lysine) affects the CD spectrum of polynucleotides, in a manner dependent on base composition and sequence. In some cases large positive or negative psi-spectra are induced, which, in the case of (dGdC)n.(dGdC)n, can be positive or negative depending on the degree of methylation of the polypeptide and the salt concentration. It is suggested that the biological effects of methylation proteins may be evoke by salt changes in the cell cycle, and that methylation can affect local interactions with nucleic acids and larger scale structure, and interactions with lipids.  相似文献   
183.
Bilateral adrenalectomy markedly reduced body weight and energy gain and energetic efficiency of adult cafeteria-fed rats but enhanced the thermogenic response to food and stimulated brown fat activity. These changes were totally prevented by replacement of the animals with corticosterone (1 mg/rat/day). Unilateral denervation of the sympathetic nerves supplying the interscapular brown adipose tissue abolished the enhanced activity resulting from adrenalectomy and inhibited thermogenic activity in brown fat from cafeteria rats with intact adrenals, but had no effect in adrenalectomised animals treated with a high dose of corticosterone.  相似文献   
184.
Interaction of the serum amyloid A proteins with phospholipid   总被引:2,自引:0,他引:2  
The serum amyloid A proteins (SAA) are transported in plasma in association with the high density lipoproteins. We have studied the solution properties of two of the polymorphic forms of SAA, SAA1 and SAA4, and compared the lipid-binding properties of SAA4 to those of the well characterized apolipoproteins, apo-A-I, apo-A-II, and apo-C-III. SAA4 was monomeric at pH 2.9 but considerable self-association was demonstrated at pH 8.2, even in the presence of 1.0 M guanidine HCl. SAA4 differed from the apolipoproteins in its ability to disrupt multilamellar dimyristoylphosphatidylcholine (DMPC) liposomes and generate bilayer discs. Apo-A-I, apo-A-II, and apo-C-III reduced the turbidity of DMPC dispersions at protein:lipid molar ratios of 1:200. SAA4, however, increased turbidity at molar ratios of 1:250 and 1:100 even when preincubated in guanidine HCl before addition to liposomes. Optical density decreased only at ratios of 1:50 and 1:25. At an SAA4:DMPC ratio of 1:50, discoidal particles (long axis, 28.1 nm; short axis, 4.4 nm) were formed which were similar to those produced by apo-C-III. Lipid binding induced changes in SAA4 conformation similar to those observed in the apolipoproteins. The alpha-helical content and intrinsic tryptophanyl fluorescence were increased and quenching of tryptophanyl fluorescence by acrylamide was reduced in the presence of DMPC. In addition, SAA4 as well as the apolipoproteins broadened the range and increased the temperature of the gel-liquid crystal transition temperature of DMPC.  相似文献   
185.
Summary Recombination of an inherited pericentric inversion of chromosome 20 has given rise to a child with partial trisomy 20p. To our knowledge no previous familial inversions of this chromosome have been described in the literature.  相似文献   
186.
Oligomycin sensitivity conferral protein (OSCP), factor 6 (F6), and ATPase inhibitor protein are all components of the ATP synthase complex of bovine mitochondria. They are encoded in nuclear DNA. Complementary DNA clones encoding the precursors of these proteins have been isolated from a bovine library by using mixtures of synthetic oligonucleotides as hybridization probes, and their DNA sequences have been determined. The deduced protein sequences show that the OSCP, F6, and inhibitor proteins have N-terminal presequences of 23, 32, and 25 amino acids, respectively. These presequences are not present in the mature proteins. It is assumed that they serve to direct the proteins into the mitochondrial matrix. The cDNA clones have also been employed as hybridization probes to investigate the genetic complexity of the three proteins in cows and humans. These experiments indicate that the bovine and human inhibitor and bovine F6 proteins are encoded by single genes but suggest the possibility of the presence in both species of more than one gene (or pseudogenes) for the OSCP.  相似文献   
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Summary In the initial phase of the geotropical reaction of the Chara rhizoid the growth difference postulated by Sievers (1967c) between the physically upper, slightly subapical flank and the lower one is demonstrated. In horizontal exposure the growth of the extreme cell apex is continued, while the growth of the lower flank is inhibited and that of the upper one is promoted. In the end phase the cell apex shows a damped oscillation until it finally reaches the vertical growth direction. The statoliths follow the oscillating growth of the cell tip from one flank to the opposite one until they are statistically equally redistributed in their normal position.—In vertical exposure under reduced turgor pressure the statoliths fall down into the extreme cell apex, where they inhibit the growth of this part of the cell wall, while the subapical wall grows transversally.—It is concluded that the statoliths inhibit the growth of the cell wall area which they cover.—The physical phase of the reaction chain, the susception, is the gravity-induced downward displacement of the statoliths. The physiological phase starts with the diversion of the acropetal transport of the Golgi vesicles to the upper part of the cell, which is caused by the block of statoliths (perception). The greater rate of vesicle incorporation into the upper flank in comparison to the lower one causes the subapical growth difference which results in the curvature (reaction).—In the case of the Chara rhizoid Golgi- and statolith-apparatus function as a self-regulating cellular system.

Herrn Prof. Dr. Dr. h. c. Kurt Mothes zum 70. Geburtstag.  相似文献   
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