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The effects of 14 days of spaceflight (SF) or hindlimb suspension (HS) (Cosmos 2044) on myosin heavy chain (MHC) isoform content of the rat soleus muscle and single muscle fibers were determined. On the basis of electrophoretic analyses, there was a de novo synthesis of type IIx MHC but no change in either type I or IIa MHC isoform proportions after either SF or HS compared with controls. The percentage of fibers containing only type I MHC decreased by 26 and 23%, and the percentage of fibers with multiple MHCs increased from 6% in controls to 32% in HS and 34% in SF rats. Type IIx MHC was always found in combination with another MHC or combination of MHCs; i.e., no fibers contained type IIx MHC exclusively. These data suggest that the expression of the normal complement of MHC isoforms in the adult rat soleus muscle is dependent, in part, on normal weight bearing and that the absence of weight bearing induces a shift toward type IIx MHC protein expression in the preexisting type I and IIa fibers of the soleus. 相似文献
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VR Machiraju MH Culig RL Heppner RA Minella JD O''Toole 《Canadian Metallurgical Quarterly》1998,65(3):625-627
BACKGROUND: Minimally invasive direct coronary artery bypass graft procedures are gaining acceptance for revision as well as primary coronary revascularization. When suitable, the left and right internal mammary arteries are preferred as bypass conduits; in other cases, the greater saphenous vein, used for standard coronary artery bypass graft procedures, may be useful to revascularize coronary artery branches during minimally invasive direct coronary artery bypass graft procedures. METHODS: We used the greater saphenous vein on three occasions during minimally invasive direct coronary artery bypass graft procedures (1) to revascularize the left anterior descending coronary artery by anastomosis to the left axillary artery in the infraclavicular region, (2) as an extension to the left internal mammary artery to reach the left anterior descending coronary artery, and (3) as a bridge from the splenic artery to bypass the distal right coronary artery. RESULTS: Postoperatively, all 3 patients had relief from symptoms of coronary artery insufficiency and none has been readmitted to the hospital with symptoms. Angiography or thallium studies were not performed to confirm graft patency because all patients were elderly and the risks of these procedures were considered to outweigh their potential benefit. CONCLUSIONS: The greater saphenous vein is a potential bypass conduit for use in minimally invasive direct coronary artery bypass graft procedures as well as for coronary artery bypass graft procedures. 相似文献
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AL Gutiérrez-Escolano F Medina VR Racaniello RM Del Angel 《Canadian Metallurgical Quarterly》1997,227(2):505-508
Specific polyclonal antibody was raised against D-aspartate (D-Asp) which had been conjugated to glutaraldehyde and was purified by affinity chromatography. Immunohistochemical staining of rat pineal gland with the antibody demonstrated the presence of D-Asp in the cytoplasm of pinealocytes, the predominant cell type in this gland. D-Asp immunoreactivity was more evident in the distal region than in the proximal region of the gland. Pinealocytes in the distal region are presumably involved in the synthesis and secretion of the pineal hormone, melatonin, and the results of staining may indicate some yet unknown role of D-Asp in the regulation of melatonin secretion. 相似文献
28.
Concentrations and emission rates of aerial ammonia, nitrous oxide, methane, carbon dioxide, dust and endotoxin in UK broiler and layer houses 总被引:2,自引:0,他引:2
CM Wathes MR Holden RW Sneath RP White VR Phillips 《Canadian Metallurgical Quarterly》1997,38(1):14-28
Standard treatment for limited stage adenocarcinoma of the breast includes lumpectomy (or a quadrantectomy), axillary node dissection, regional radiation therapy and, if the prognostic factors are unfavourable, chemotherapy and/or hormone therapy. This is supported by the results of American and European randomised trials. There have been many attempts at improving the modalities of conservative surgery and postoperative radiation therapy in order to maximize local control and minimize late sequellae. It is also likely that induction chemotherapy and external beam radiotherapy applied in selected cases increase the proportion of patients who can be offered conservative surgery. 相似文献
29.
C. Maurice D. Piot H. Klocker J. H. Driver 《Metallurgical and Materials Transactions A》2005,36(4):1039-1047
A thoroughly tested, high-temperature channel-die compression (CDC) rig is described for simulating hot plane strain compression
of metallic alloys up to 500 °C. The equipment is currently used to characterize the flow stress and microstructure evolution
in hot-rolled Al alloys. It has been validated by several tests involving (1) metallographic analysis of deformed samples;
(2) flow stress comparisons with the same, or similar alloys deformed in conventional uniaxial or plane strain compression;
and (3) microstructure and texture measurements. The use of modern lubricants enables one to obtain accurate flow stresses
and true plane strain deformations that are homogeneous over 80 pct of the sample. The equipment also features rapid heating
and cooling systems to minimize thermally-induced microstructure changes. Some results on high-temperature slip systems, hot
deformation textures, and microstructures, and the behavior of constituent particles are outlined to illustrate the advantages
of the technique. 相似文献
30.
ME Reilly D Mantle PJ Richardson J Salisbury J Jones TJ Peters VR Preedy 《Canadian Metallurgical Quarterly》1997,21(5):792-798
The complexity of the spot patterns of two-dimensional electrophoresis gels made it necessary to use image processing techniques to analyze the gels. An important issue in the analysis is the detection and quantification of the protein spots. In this paper we describe a new technique to segment and model the different spots. For the segmentation of a gel into its different spot regions we apply a watershed technique, which is robust and efficient. For the quantification of the spots, a new spot model is constructed, based on diffusion principles. Besides the advantage of having a physical interpretation, the model is demonstrated to be superior to the commonly used Gaussian models. 相似文献