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Leonard J. Yamshon 《The Western journal of medicine》1958,89(5):333-334
Frozen shoulder, rare in the young but more easily incurred after age 40, is a result of immobilization from any cause. Atrophy is the first phase, followed by shortening of soft tissues, pain on extension, spasm contractures and adhesions.Mobilization is urgent to prevent contractures. Rotation is the most important exercise, and should be done with the upper arm supported in nearly horizontal extension to prevent the humeral head from impinging on the acromion. From this position the forearm, lifting or pulling down in a forward are against weights and pulleys, restores the rotatory power of the shoulder. 相似文献
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Kenneth W. Gasser Leonard B. Kirschner 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1987,157(4):469-475
Summary The relationship between alkaline phosphatase and environmental salinity was examined in the rainbow trout and the migratory rainbow (steelhead),Salmo gairdneri. The enzyme activity in tissues involved in osmoregulation was strongly correlated with the adaptation salinity and thus to the degree of salt and fluid transport in those tissues. After transfer from freshwater to seawater, the specific activity of the enzyme increased over 260% in the intestine, decreased by 50% in kidney, and was unchanged in the liver, an organ not directly involved in osmoregulation. The sea-run steelhead trout response was similar to the nonmigratory rainbow; although, the pre-migratory transformation (smoltification) had no effect on enzyme activity. Amino acid inhibitors of alkaline phosphatase significantly reduced fluid absorption in the isolated intestine of rainbow trout, reaffirming the relationship between the enzyme and fluid movement. Electrophoretic identification of trout alkaline phosphatase isozymes, clearly distinguishes the enzyme from different tissue origins. However, from the analysis of intestinal electrophoretic patterns, osmoregulatory adjustments are not associated with the induction of new alkaline phosphatase isozymes, or in the large scale preferential stimulation of one of the two existing intestinal isozymes over the other. 相似文献
17.
Environmental factors influencing the occurrence of juvenile fish in the mangroves of Pagbilao,Philippines 总被引:2,自引:1,他引:1
Leonard Pinto 《Hydrobiologia》1987,150(3):283-301
128 fish species belonging to 54 families were collected from the mangroves of Pagbilao. Ambassis kopsi (Ambassidae) was the most abundant species.Fourteen environmental factors were correlated to the catch per unit time for some species. The occurrence of A. kopsi was positively correlated to nitrate in the water, carbon in the sediments and litter fall. Out of the 8 species investigated, 6 were positively correlated to litter fall. Three species showed positive correlation to phosphate in the water, two to organic carbon in the sediments, nitrate, silicate and pH, and one to salinity and carotenoids in water. The biomass of the total catch was correlated to carbon in the sediments and litter fall. 相似文献
18.
Overexpression of the dnaA gene in Escherichia coli B/r: chromosome and minichromosome replication in the presence of rifampin. 总被引:7,自引:4,他引:3 下载免费PDF全文
O Pierucci C E Helmstetter M Rickert M Weinberger A C Leonard 《Journal of bacteriology》1987,169(5):1871-1877
The replication of chromosomes and minichromosomes in Escherichia coli B/r was examined under conditions in which the dnaA gene product was overproduced. Increased levels of the DnaA protein were achieved by thermoinduction of the dnaA gene, under the control of the lambda pL promoter, or by cellular maintenance of multicopy plasmids carrying the dnaA gene under the control of its own promoters. Previous work has shown that overproduction of DnaA protein stimulates replication of the chromosomal origin, oriC, but that the newly initiated forks do not progress along the length of the chromosome (T. Atlung, K. V. Rasmussen, E. Clausen, and F. G. Hansen, p. 282-297, in M. Schaechter, F. C. Neidhardt, J. L. Ingraham, and N. O. Kjeldgaard, ed., The Molecular Biology of Bacterial Growth, 1985). In the present study, it was found that overproduction of DnaA protein caused both a two- to threefold increase in the amount of residual chromosome replication and an extended synthesis of minichromosome DNA in the presence of rifampin. The amount of residual chromosome replication was consistent with the appearance of functional replication forks on the majority of the chromosomes. Since the rate of DNA accumulation and the cellular DNA/mass ratios were not increased significantly by overexpression of the dnaA gene, we concluded that the addition of rifampin either enabled stalled replication forks to proceed beyond oriC or enabled new forks to initiate on both chromosomes and minichromosomes, or both. 相似文献
19.
M C Romano R D Eckardt P E Bender T B Leonard K M Straub J F Newton 《The Journal of biological chemistry》1987,262(4):1590-1595
omega-Hydroxylation of leukotriene B4 (LTB4) has been reported in human and rodent polymorphonuclear leukocytes; preliminary information indicates that this metabolism is cytochrome P-450 dependent. Therefore, these studies were initiated to characterize the cytochrome P-450-dependent metabolism of LTB4 in other tissues. LTB4 was metabolized by rat hepatic microsomes to two products, 20-hydroxy(omega)-LTB4 and 19-hydroxy(omega-1)-LTB4. The formation of these metabolites was both oxygen and NADPH dependent indicating that a monooxygenase(s) was responsible for these reactions. The apparent Km and Vmax for LTB4 omega-hydroxylase were 40.28 microM and 1202 pmol/min/mg of protein, respectively. In contrast, the apparent Km and Vmax for LTB4 (omega-1)-hydroxylase were 61.52 microM and 73.50 pmol/min/mg of protein, respectively. Both LTB4 omega- and (omega-1)-hydroxylases were inhibited by metyrapone in a concentration-dependent fashion. However, SK&F 525A inhibited LTB4 (omega-1)- but not omega-hydroxylase. In contrast, alpha-naphthoflavone decreased LTB4 omega- but not (omega-1)-hydroxylase activities. The differences in the Km apparent for substrate as well as the differential inhibition by inhibitors of cytochrome P-450 suggest that the omega- and (omega-1)-hydroxylations of LTB4 in hepatic microsomes are mediated by different isozymes of P-450. Furthermore, several additional characteristics of LTB4 hydroxylases indicate that these isozymes of P-450 may be different from those which catalyze similar reactions on medium-chain fatty acids, such as laurate and prostaglandins. 相似文献
20.
J R Trudell 《Free radical biology & medicine》1987,3(2):133-136
We have suggested the use of ethyl acetate for extraction of hydroxyl or superoxide radical adducts of the spin trap phenyl N-tert-butyl nitrone (PBM). The technique produced EPR spectra with narrow line widths, the radical adducts were more stable, and there were sufficiently large differences between the isotropic nitrogen hyperfine coupling constant (alpha N) and the beta hydrogen coupling constant (alpha H beta) for both the hydroxyl and superoxide radical adducts to allow their simultaneous quantitation in mixtures. However, Kalyanaraman, Mottley, and Mason have suggested that our assignments of alpha N and alpha H beta were incorrect and that extraction of spin-trapped adducts into ethyl acetate is not as useful as we had proposed. This paper demonstrates that their objections are unfounded and are based on a computational error that they made when they attempted to calculate the hyperfine splittings in their spectra. 相似文献