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41.
In chronic viral hepatitis B and C the development of intestinal dysbacteriosis and high occurrence of concomitant diseases of the gastrointestinal tract were observed. In cases of increased dysbacteriosis degree and in the presence of concomitant diseases the blood plasma of patients exhibited higher activity in reaction with the of amebocytes lysate obtained from crabs of the genus Limulus. A suggestion was made that the endotoxin of Gram negative intestinal microflora could probably play some role in the development of pathological processes in chronic viral hepatitis B and C.  相似文献   
42.
Type I restriction endonucleases are composed of three subunits, HsdR, HsdM and HsdS. The HsdR subunit is absolutely required for restriction activity; while an independent methylase is composed of HsdM and HsdS subunits. DNA cleavage is associated with a powerful ATPase activity during which DNA is translocated by the enzyme prior to cleavage. The presence of a Walker type I ATP-binding site within the HsdR subunit suggested that the subunit may be capable of independent enzymatic activity. Therefore, we have, for the first time, cloned and over-expressed the hsdRgene of the type IC restriction endonuclease EcoR124II. The purified HsdR subunit was found to be a soluble monomeric protein capable of DNA- and Mg2+-dependent ATP hydrolysis. The subunit was found to have a weak nuclease activity both in vivo and in vitro, and to bind plasmid DNA; although was not capable of binding a DNA oligoduplex. We were also able to reconstitute the fully active endonuclease from purified M. EcoR124I and HsdR. This is the first clear demonstration that the HsdR subunit of a type I restriction endonuclease is capable of independent enzyme activity, and suggests a mechanism for the evolution of the endonuclease from the independent methylase.  相似文献   
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Background  

Coalescent simulations are playing a large role in interpreting large scale intra-specific sequence or polymorphism surveys and for planning and evaluating association studies. Coalescent simulations of data sets under different models can be compared to the actual data to test the importance of different evolutionary factors and thus get insight into these.  相似文献   
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Fibronectin (FN) solution purified from human blood plasma significantly increased the breaking strength of skin wounds in rats, when applied locally and/or intravenously. The best effect (more than 2-fold) was revealed after combined local and i. v. application of FN. Maximum stimulating activity was observed on the 3rd postoperative day, directly indicating the importance of FN for the early phases of wound healing. The data suggest the possibility of using FN preparations for the stimulation of tissue repair processes.  相似文献   
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Estimates of tag retention and tagging-related mortality are essential for mark-recapture experiments. Mortality and tag loss were estimated from 15 tigerfish Hydrocynus vittatus marked using Hallmark model PDL plastic-tipped dart tags released into a 1 730 m2 pond at Kamutjonga Inland Fisheries Institute, Namibia, and inspected bi-monthly for the presence or absence of tags. No mortality was observed during the experiment. All marked fish had lost their tags after 10 months and 50% tag loss was estimated at 3.9 months. The high tag loss rate indicates that PDL plastic-tipped dart tags are not suitable for long-term studies on this species.  相似文献   
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We describe abnormal embryonic development leading to death of 50% of embryos in all-female lines of Adalia and Harmonia infected with an androcide Spiroplasma. The arrest of embryonic development takes place at different stages throughout embryogenesis. Oogenesis of the infected beetles proceeds without any significant morphological changes.  相似文献   
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