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In the last decade a good number of biotechnical methods have been developed. They are available in medical, biological, and ecological fields of work as well as techniques that can replace animal experiments. These methods have been developed on the basis of researchwork in andrology (AI and cryoconservation of spermatozoa), endocrinology (hormonal control of reproduction) and the availability of industrial produced hormones and their analog. On the other hand practical clinical techniques for examination like the availability of sonography advice and clinical practical techniques for non-surgical recovery and transplantation of gamets and embryos have been the prerequisites for a successful work in this field of action. These fields of action are extended from breeding aspects (genetical progress) over the control of epidemics to the exportation of genetic material (especially developing countries to overcome hygienic and adaptation problems), the creation of gen-pools (conservation of breeds-species) and as well as the elimination of genetic defects like BLAD or DUMPS by help of PCR-techniques or the identification of positive characters like milk components and sexing of embryos. The industrial use of bioproducts produced by especially designed biosystems is in work but in Germany not possible by reasons of legislative restrictions. In the light of these developments the veterinary fields of work should be discussed and focussed towards an understanding that the veterinarian should be active and in a polposition in the processing of reproduction and production and presentation of food of animal origin by using these new technologies.  相似文献   
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In presenting a unifying concept for chronic inflammation and lymphoid organogenesis, we suggest that lymphotoxin's (LT, LT-alpha, TNF-beta) crucial role in these processes is pivotal and similar. Chronic inflammatory lesions that developed in the kidney and pancreas at the sites of transgene expression in rat insulin promoter-LT (RIP-LT) mice resembled lymph nodes with regard to cellular composition (T cells, B cells, plasma cells, and antigen-presenting cells), delineated T and B cell areas, primary and secondary follicles, characteristic morphologic and antigenic (ICAM-1, VCAM-1, MAdCAM-1, and PNAd) features of high endothelial venules, and ability to respond to antigen and undergo Ig class switching when obtained from mice immunized with SRBC. The vascular changes, with the exception of PNAd, appear to be the direct consequence of transgene derived LT expression, as they were also observed in RIP-LT mice lacking mature T and B cells. These data show that LT-induced chronic inflammation has the characteristics of organized lymphoid tissue.  相似文献   
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An alkylation method of docetaxel at the C-10 position has been established by a radical coupling reaction using a 10-xanthate derivative of 7-O-TES-10-deacetylbaccatin III and appropriate alkenes. In addition the cytotoxic activity of 10-alkylated docetaxel analogs was evaluated. Among these analogs, a derivative having a methoxycarbonyl group at the end of the alkyl moiety exhibited more potent cytotoxic activity than docetaxel.  相似文献   
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Utilizing the Escherichia coli/pGex vector expression system incorporating a thrombin cleavage site, full-length (residues -6-243) and truncated forms of proapolipoprotein AI (proapoAI), terminating at amino acid residues 222, 210, 150, and 135, were purified to levels of at least 5 mg/L, after thrombin cleavage. Assessed by circular dichroism, the helical contents of L-alpha-dimyristoylphosphatidylcholine-associated forms of human plasma-derived apolipoprotein AI (apoAI) and recombinant proapoAI were comparable, being 69% and 65%, respectively. Circular dichroism measurements of the lipid-associated complexes of the truncated forms showed that between the sequence of residues 150-222 no additional helicity was gained until the carboxyl-terminal sequence was present in the molecule, indicating that the carboxyl terminus of the protein is required for the formation of helix within this central region. While tryptophan residues were more than 86% accessible, as assessed by iodide quenching, in the two truncated forms, proapoAI-6-135 and proapoAI-6-150, for both free and complexed protein, this figure fell to about 50% for full-length recombinant proapoAI, further indicating the influence of the carboxyl terminus on the structure of the whole protein. While cross-linking human plasma apoAI in solution with dithiobis-(succinimidyl propionate) revealed high molecular weight oligomers by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, recombinant proapoAI did not strongly form complexes larger than trimers. None of the truncated proapoAI molecules formed oligomers larger than trimers. The shortest form, proapoAI-6-135, only dimerized. Initial results from lecithin:cholesterol acyltransferase activation (apoAI peptide concentration 0.2 microM) indicated that truncation of the 21 carboxy-terminal amino acids resulted in a drop of approximately 53% in activation and 33 residues a drop of 67% relative to the full-length protein. Overall these results indicate the important influence of the carboxyl terminus on the structure of apoAI.  相似文献   
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The case of a 69-year-old man with liver cirrhosis, thrombocytopenia, unstable angina, and a history of previous coronary artery bypass grafting (CABG) is presented. The patient under-went successful repeat CABG through lateral thoracotomy on the beating heart without extracorporeal circulatory support.  相似文献   
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