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Interaction of human low-density lipoproteins (LDL) with homologous fibronectin fixed on collagen-Sepharose was studied. LDL were digested with pepsin, the degree of hydrolysis amounting to 10%. Upon passing modified LDL through a fibronectin-collagen-Sepharose column the desorption of fibronectin occurred. Addition of the increasing amount of fibronectin to the pepsin-treated LDL solution in the presence of Ca2+ ions led to the formation of LDL-fibronectin insoluble complexes. Interaction of native LDL with fibronectin was not observed. The data suggest that enzymatic modification of LDL increasing interaction of modified LDL with fibronectin, a component of extracellular matrix, could promote the accumulation of such LDL in arterial walls.  相似文献   
975.
Lethal mutations in the T/t complex cause stage-specific morphologic abnormalities during early embryogenesis of mice. Although mutant embryos are lethal at the early stages of development, we have succeeded in establishing several cell lines from one of these mutants ( T/T ). Mutant-specific abnormality was not observed in gross morphology and growth patterns of cells. They, however, retained the characters of freshly dissociated embryonic cells to form smaller aggregates than the wild-type in rotation-mediated aggregation.
One of the T/T cell lines (T-1) formed tumors when injected into one-day-old syngeneic and allogeneic host, Expression of H-2 antigens was serologically studied with H-2 specificity 5 as a marker antigen. All lines except T-1 were shown to have this specificity.  相似文献   
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Trapezonotus dispar Stål, 1872 is subdivided into two subspecies, T. dispar dispar (Europe) and T. dispar breviceps Jakovlev, 1882 (= T. seductor Horváth, 1883) (Caucasus and Asia Minor). T. inglorius Vinokurov, 1990 is synonymized with T. desertus Sedienstücker, 1951.  相似文献   
980.
Simple demographic and infectious disease models of buffaloes and other domestic hosts for animal trypanosomosis (surra) caused by Trypanosoma evansi were developed. The animal models contained deterministic and stochastic elements and were linked to simulate the benefit of control regimes for surra in village domestic animal populations in Mindanao, Philippines. The impact of the disease on host fertility and mortality were key factors in determining the economic losses and net-benefit from the control regimes. If using a high (99%) efficacy drug in surra-moderate to high risk areas, then treating all animals twice each year yielded low prevalence in 2 years; targeted treatment of clinically sick animals, constantly monitored (monthly), required 75% fewer treatments but took longer to reach a low prevalence than treating all animals twice each year. At high drug efficacy both of these treatment strategies increased the benefit over untreated animals by 81%. If drug efficacy declined then the benefit obtained from twice yearly treatment of all animals declined rapidly compared with regular monitoring and targeting treatment to clinically sick animals. The current control regimen applied in the Philippines of annual sero-testing for surra and only treating sero-positive animals provided the lowest net-benefit of all the control options simulated and would not be regarded as effective control. The total net-benefit from effective surra control for a typical village in a moderate/high risk area was 7.9 million pesos per annum (US $158,000). The value added to buffaloes, cattle, horses, goats/sheep and pigs as a result of this control was US $88, $84, $151, $7, $114 per animal/year, respectively.  相似文献   
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