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An electron microscopical and histochemical investigation of bioptates obtained from the external broad femoral muscle of 74 sportsmen-skaters has been performed. Structural adaptation of the muscles to speed loadings and to endurance loadings has been analysed taking into consideration contents of muscle fibers (MF) of various type. Peculiarities in ultrastructural organization of the skeletal MF in the sprinter- and stayer-skaters, who undergo training according to a special program, are described; the character of the muscle changes is also followed in the sportsmen who undergo training according to the program that does not correspond to the contents of their MF. Lesions in the latter up to the necrotic ones are mostly found in the muscles of the stayer-skaters, as well as in the sprinters trained according to the stayer program. Presence of essential destructive alterations of the muscles in the skaters, especially in those whose contents of slow muscles do not correspond to their specialization, demonstrates, evidently, the fact that the given physical loading is not adequate to the functional or potential possibilities of the organism.  相似文献   
184.
It has been shown in the experiment with albino rats that the prolonged influence of stable noise (90 dB) results in a shift of the redox equilibrium in the thiol-disulphide and ascorbate systems of the adrenal gland and myocardium tissues towards oxidation and the activity of glucoso-6-phosphate dehydrogenase and superoxide dismutase decreases. A concept on the pathogenetic role of the redox equilibrium disturbance in the thiol-disulphide system, in particular, in the development of noise pathology is suggested.  相似文献   
185.
The male (CBA X C57BL) FI mice received 125 mg of hydrocortisone per kg body weight intraperitoneally. The functional activity of neutrophils has been evaluated by means of nitroblue terazolium test (NBT-test) values taken before or after heat-killed S. marcescens cell stimulation in vitro by 2, 12, 24 h 3, 7 or 14 days post hormonal treatment. Throughout the 1st day after hydrocortisone administration the NBT-test values taken prior to as well as post microbial neutrophil stimulation were steadily increased. This effect could be seen as early as 2 h post hormone administration and it was linked with growing leukopenia and total decrease of blood granulocyte content. By the 3rd day the same very values turned up to become normal. The NBT-test values after microbial stimulation of neutrophils were 1.7 or 2.4 lower after hydrocortisone had been added to blood in vitro in a dose 3.5 X 10(-6) M or 7 X 10(-5) M.  相似文献   
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Polyhydroxyalkanoates (PHAs) are biodegradable polymers produced by microbes to overcome environmental stress. Commercial production of PHAs is limited by the high cost of production compared to conventional plastics. Another hindrance is the brittle nature and low strength of polyhydroxybutyrate (PHB), the most widely studied PHA. The needs are to produce PHAs, which have better elastomeric properties suitable for biomedical applications, preferably from inexpensive renewable sources to reduce cost. Certain unique properties of Bacillus subtilis such as lack of the toxic lipo-polysaccharides, expression of self-lysing genes on completion of PHA biosynthetic process – for easy and timely recovery, usage of biowastes as feed enable it to compete as potential candidate for commercial production of PHA.  相似文献   
188.
Adenoviral (Ad) vectors have been used for a variety of vaccine applications including cancer and infectious diseases. Traditionally, Ad-based vaccines are designed to express antigens through transgene expression of a given antigen. However, in some cases these conventional Ad-based vaccines have had sub-optimal clinical results. These sub-optimal results are attributed in part to pre-existing Ad serotype 5 (Ad5) immunity. In order to circumvent the need for antigen expression via transgene incorporation, the “antigen capsid-incorporation” strategy has been developed and used for Ad-based vaccine development in the context of a few diseases. This strategy embodies the incorporation of antigenic peptides within the capsid structure of viral vectors. The major capsid protein hexon has been utilized for these capsid incorporation strategies due to hexon''s natural role in the generation of anti-Ad immune response and its numerical representation within the Ad virion. Using this strategy, we have developed the means to incorporate heterologous peptide epitopes specifically within the major surface-exposed domains of the Ad capsid protein hexon. Our study herein focuses on generation of multivalent vaccine vectors presenting HIV antigens within the Ad capsid protein hexon, as well as expressing an HIV antigen as a transgene. These novel vectors utilize HVR2 as an incorporation site for a twenty-four amino acid region of the HIV membrane proximal ectodomain region (MPER), derived from HIV glycoprotein gp41 (gp41). Our study herein illustrates that our multivalent anti-HIV vectors elicit a cellular anti-HIV response. Furthermore, vaccinations with these vectors, which present HIV antigens at HVR2, elicit a HIV epitope-specific humoral immune response.  相似文献   
189.
Lipid droplets (LDs), also called adiposomes, are found in many eukaryotic cells, and are highly upregulated in lipid-storage cells, such as adipocytes. The mechanism by which adiposomes and their component neutral lipids are degraded is an important health issue with the rapidly spreading epidemic of obesity. Recently, a novel triglyceride lipase (adipose triglyceride lipase (ATGL)) that catalyses the initial step in triglyceride hydrolysis in adipocyte LDs was identified. Here, we show that ATGL also functions in non-adipocyte cells, and has an important role in LD degradation in these cells. Overexpression of wild-type ATGL causes a marked decrease in LD size, whereas a catalytically inactive mutant retains the ability to localize to LDs, but is unable to decrease their size. Depletion of ATGL by RNA interference leads to a significant increase in the size of LDs. These results show that ATGL has an important role in LD/adiposome turnover in mammalian cells.  相似文献   
190.

Background  

Hypoxia-inducible factors (HIFs) are involved in adaptive and survival responses to hypoxic stress in mammals. In fish, very little is known about the functions of HIFs.  相似文献   
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