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121.
122.
This paper reports the experimental transmission of a bird parasite into jirds. Infective larvae of Cardiofilaria nilesi obtained from laboratory colonized Coquillettidia crassipes mosquitoes which had fed on an infected chicken were inoculated subcutaneously into jirds. The number of larvae per jird varied from 10 to 228. Microfilaraemia appeared 22 to 89 days after inoculation of the infective larvae. Experiments were carried out with 24 jirds through six generations extending over a period of 22 months and 17 produced patent infections. At present 8 infected jirds are being maintained in the laboratory; their patent periods ranging from 6 to 13 months. However, the longest patent period observed was about thirteen months. The percentage of adults recovered in autopsied jirds ranged from 0 to 40 with an average of 16. The chicken showed a microfilarial periodicity with the peak microfilarial density around 2200 hours. However, in jirds there was a change in sub-periodicity. This model in the jird may be very useful for the screening of filaricides and in immunological work. 相似文献
123.
Platelet-collagen interaction. Inhibition by a monoclonal antibody raised against collagen receptor 总被引:4,自引:0,他引:4
Monoclonal antibodies to the purified platelet type I collagen receptor were produced to study platelet receptor function. The antibody specifically reacted with the platelet receptor in immunoblot experiments. The IgG purified from the monoclonal antibodies and isolated Fab' fragments inhibited the binding of radiolabeled alpha 1(I) chain to washed platelets competitively. Soluble and fibrillar type I collagen-induced platelet aggregations were inhibited by purified IgG suggesting that soluble and fibrillar collagens shared a common receptor. The adhesion of platelets to an artificial collagen matrix was also inhibited by the monoclonal antibody. However, adenosine diphosphate-induced platelet aggregation was not inhibited by the same amount of IgG that inhibited collagen-induced platelet aggregation. The results suggest that collagen-induced platelet aggregation is mediated through the interaction of collagen with the platelet receptor. 相似文献
124.
Summary The production of 9-cis-1, 18-octadecenedioic acid from different substrates by the mutant S76 of Candida tropicalis was studied. It was found that the mutant could convert oleyl alcohol, oleic acid, and methyl oleate to 9-cis-1, 18-octadecenedioic acid through either the diterminal oxidation of the alcohol or the -oxidation of the terminal methyl group of the mono acid. The geometric configuration of the product was identified by different analytical methods. The results demonstrated that no change in the geometric configuration of molecular structure happened during the bioconversion of such unsaturated substrates to 9-dioic acid. To enhance the production of this dioic acid in the medium, calcium carbonate was added as a trapping agent. The IR spectrum, 1H NMR and 13C-satellite spectra of this compound were presented.Dedicated to Professor Dr. K. Esser on the occasion of his 65th birthday 相似文献
125.
Protection of mice against Sendai virus pneumonia by non-neutralizing anti-F monoclonal antibodies 总被引:1,自引:0,他引:1
Y Mochizuki T de Ming T Hayashi M Itoh H Hotta M Homma 《Microbiology and immunology》1990,34(2):171-183
Nine monoclonal antibodies (MAbs) directed to F protein of Sendai virus were obtained and characterized for their protective ability against Sendai virus infection in mice. None of the MAbs showed hemagglutination-inhibition (HI), hemolysis-inhibition (HLI), or neutralization (NT) activities in vitro when assayed by standard methods. Some of the MAbs, however, showed complement-requiring NT (C-NT) and complement-requiring hemolysis (C-HL) activities when assayed in the presence of complement. Passive immunization experiments revealed that the MAbs with higher C-NT and C-HL activities showed protective activity against Sendai virus pneumonia in mice, and that some MAbs with IgG1 isotype having neither C-NT nor C-HL activity also showed the protective activity. Digestion of the MAbs with pepsin which split immunoglobulin molecules into F(ab')2 and Fc fragments greatly suppressed the protective activity. These results suggest that not only complement-mediated immunological responses such as immune virolysis but also antibody-dependent cellular cytotoxicity (ADCC) and/or immune phagocytosis, in which complement system is not necessarily involved, play an important role in the protection of mice from Sendai virus infection. 相似文献
126.
127.
维西香茶菜的二萜成分 总被引:1,自引:0,他引:1
维西香茶菜Rabdosia weisiensis C. Y. Wu产云南西北部海拔2600米沟谷中,其化学成分的研究未见报道。从该植物叶的乙醚提取物中,分得两个二萜成分,一为已知成分trichorabdal A(2),一为新成分,命名为维西香茶菜甲素weisiensin A(1)。 维西香茶菜甲素weisiensin A(1),C_(26)H_(36)O_9,mp 298—300℃,其~(13)C NMR谱显示存在三个CH_3,三个CH_2,八个CH,三个四取代碳,三个Ac,二个烯碳和一个羰基 相似文献
128.
Gary K. Scott Peter L. Davies Ming H. Kao Garth L. Fletcher 《Journal of molecular evolution》1988,27(1):29-35
Summary The organization of antifreeze protein (AFP) genes in the yellowtail flounder was investigated by Southern blotting and the characterization of clones from a genomic library. This flounder, like the closely related winter flounder, has a set of 10–12 linked but irregularly spaced AFP genes. However, it lacks the tandemly amplified set of 20 such genes that are present in the winter flounder. DNA sequence analysis of a tandemly repeated gene from winter flounder showed that it can code for one of the two most abundant AFP components in the serum. Consistent with this higher AFP gene dosage, the peak serum AFP level in midwinter was 9 mg/ml in the winter flounder and only 4 mg/ml in the yellowtail flounder. A recent amplification of the AFP gene in the winter flounder lineage might be responsible for the higher serum AFP levels in this fish. This increase in gene dosage might have helped the winter flounder colonize the ice-laden, shallow-water niche that it currently occupies along the east coast of North America. Genomic Southern blotting of two other righteye flounders, the smooth flounder and the American plaice, illustrates another example of a differential amplification of AFP genes that correlates with a species' exposure to ice. 相似文献
129.
人小细胞肺癌的发病率虽不及非小细胞肺癌,但其五年生存率却相对低得多,这两种细胞类型不仅在病理类型上表现不同,在许多其它性质上也表现不同。小细胞肺癌是一种异质性疾病,它由几种形态不同的瘤细胞组成,包括非小细胞肺癌在内;它易早期转移,能在肝、脑和骨髓中繁殖,具有L-Dopa胱羧酶,神经原特异的烯醇化酶(enolase),能合成神经递质和多肽激素蛙皮肽等特性。目前已有关于小细胞肺癌的单克隆抗体的报道,我们采用美国N I H建立的小细胞肺癌细胞株SH-77作免疫原,目前尚未见有关抗该细胞株的单克隆抗体的报道,现将我们制备的三个单抗体及其初步特异性鉴定结果简报如下 相似文献
130.