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111.
112.
Human T-lymphotropic virus type III (HTLV-III) is thought to play an etiologic role in the development of the acquired immune deficiency syndrome (AIDS). In this study the serologic characterization of a new simian retrovirus that is related to HTLV-III is described. This new virus, here referred to as STLV-III, was isolated from sick macaques at the New England Regional Primate Research Center. Radioimmunoprecipitation analysis revealed STLV-III-specific proteins of 160, 120, 55, and 24 kilodaltons, all similar in size to the major gag and env proteins of HTLV-III. These antigens were recognized by representative macaque serum samples and human reference serum samples positive for HTLV-III antibodies. Monoclonal antibodies directed to p24, the major core protein of HTLV-III, also immunoprecipitated a 24-kilodalton species in lysates of cells infected with the macaque virus. This HTLV-III-related virus, which naturally infects a nonhuman primate species, may provide a useful model for the study of HTLV-III and the pathogenesis of AIDS.  相似文献   
113.
Soluble products of either Epstein-Barr virus (EBV)-infected B cells or activated monocytes promote the proliferation of EBV-infected B cells and permit their growth at low cell densities. This suggests that growth factors are important for B-cell immortalization by EBV. In this study, a monocyte-derived factor that promotes the growth of EBV-infected b cells was purified and identified as interferon-beta 2 (IFN-beta 2), which is also known as 26-kilodalton protein, B-cell differentiation factor (BSF-2), and interleukin-6 (IL-6). The purified protein has a specific activity of approximately 4 X 10(7) units per milligram of protein in assays of B-cell growth. Thus, IFN-beta 2/BSF-2 is a B-cell growth factor that promotes the proliferation of human B cells infected with EBV.  相似文献   
114.
Methotrexate coupled to maleylated bovine serum albumin was taken up efficiently through the "scavenger" receptors present on macrophages and led to selective killing of intracellular Leishmania mexicana amazonensis amastigotes in cultured hamster peritoneal macrophages. The drug conjugate was nearly 100 times as effective as free methotrexate in eliminating the intracellular parasites. Furthermore, in a model of experimental cutaneous leishmaniasis in hamsters, the drug conjugate brought about more than 90% reduction in the size of footpad lesions within 11 days. In contrast, the free drug at a similar concentration did not significantly affect lesion size. These studies demonstrate the potential of receptor-mediated drug delivery in the therapy of macrophage-associated diseases.  相似文献   
115.
Isolation of T-cell tropic HTLV-III-like retrovirus from macaques   总被引:125,自引:0,他引:125  
The isolation of a T-cell tropic retrovirus from three immunodeficient macaques and one macaque with lymphoma is described. The morphology, growth characteristics, and antigenic properties of this virus indicate that it is related to the causative agent of acquired immune deficiency syndrome in humans (HTLV-III or LAV). This virus is referred to as simian T-lymphotropic virus type III (STLV-III) of macaques. The existence of a cytopathic, T-cell tropic virus resembling HTLV-III in monkeys may facilitate study of disease induction and vaccine development in an animal model.  相似文献   
116.
Female macaque monkeys self-administered high doses of alcohol (2.9 to 4.4 grams per kilogram per day) for 3 to 6 1/2 months. Amenorrhea, atrophy of the uterus, decreased ovarian mass, and significant depression of luteinizing hormone levels were associated with chronic alcohol intoxication. Reproductive system failure in female primates following self-induced dependence on alcohol parallels the results of clinical studies of alcoholic women.  相似文献   
117.
Five varieties of Amaranthus cruentus were planted in 3 localities at different altitudes above sea level. They were subjected to equivalent agronomic practices and harvested at 120–130 days. The seeds were removed and dried to 12% moisture. The seeds from each variety were analyzed for total fat, palmitic, stearic, oleic and linolenic acids and squalene contents. Oil content varied from 5.83 to 7.13%, palmitic acid from 17.06 to 21.35%, stearic acid from 3.05 to 3.80%, oleic acid from 20.26 to 32.01% and linoleic acid from 33.52 to 43.88%. The values for oil and fatty acid contents were similar to those found in the literature. The differences in the analytical values of the present study were not statistically significant for variety or for location.Squalene content varied from 2.26 to 5.94% of the oil. This variability is similar to that reported previously by other workers. Statistical analysis showed significant difference for localities but not for varieties. It is suggested that environmental conditions, such as temperature and water availability, may lead to a greater accumulation of squalene in the grain.  相似文献   
118.
Spinach (Spinacia oleracia) and amaranth (Amaranthus tricolor) leaves were stored in polyethylene bags and without packing for 24 and 48 hours in a refrigerator at 5 and 30 °C in polyethylene bags. The fresh leaves were also dried (oven and sun); blanched (5, 10 and 15 min) and cooked in an open pan and a pressure cooker. The processed leaves were analysed for total and extractable calcium and zinc content. The Ca and Zn content of these leaves varied from 1320 to 2120 and 11.70 to 12.60 mg/100 g DM and the percentage HCl-extractability was 77.82 to 81.92 and 85.16 to 86.15, respectively. No significant effects of drying and storage were observed on total Ca and Zn content and HCl-extractability while blanching and cooking resulted in significant improvement of HCl-extractibility of these two minerals. Thus, cooking and blanching are good ways to improve the HCl-extractibility of Ca and Zn.  相似文献   
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