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Background
In this study the concentration of lysozyme in blood plasma of Microtus agrestis, Clethrinomys glareolus, Apodemus sylvaticus, BK rats and outbred white mice before and after infection with culture forms of Trypanosoma microti, T, evotomys, T. grosi, T. lewisi and T. musculi respectively was measured.Methods
Blood samples of rodents, Microtus agrestis, Clethrionomys glareolus, Apodemus sylvaticus, BK rats and outbred mice infected with T. microti, T. evotomys, T. grosi, T. lewisi and T. musculi respectively were collected in heparinized micro- tubes immediately before inoculation and 3, 6, 12, 24, 48, 96 and more than 400 days after intra- perituneal inoculation with 5×105of their homologous trypanosome parasites of which more than half were metacyclic trypomastigote in 0.2 ml of culture medium. Micro- tubes were centrifuged and plasma samples were separated and the lysozyme activity was measured by the agar method.Results
Levels of lysozyme rose rapidly three to six days after the inoculation to ten to twenty than their pre- infection levels. They then gradually decreased, although after more than one year they were still two to ten folds higher than controls. The highest level measured occurred in rats infected with T. lewisi and the lowest in A. sylvaticus infected with T. grosi. After one year the highest concentration of lysozyme was in mice infected with T. musculi and lowest in A. sylvaticus.Conclusion
Persistent enhanced lysozyme levels may prevent re- infection with trypanosomes. 相似文献86.
静脉药瘾者人类免疫缺陷病毒核酸测定及亚型分析 总被引:1,自引:1,他引:1
目的:了解静脉药瘾者人类免疫缺陷病毒(HIV)感染情况及感染亚型,追踪传染源,预测未来流行株。方法:对1997年从新疆至杭州的15例静脉药瘾者血清进行抗-HIV的初步筛选,结果为阳性者再行免疫印迹(Western blot)、套式聚合酶链反应(Nest-PCR)及HIV核酸序列分析,结果:15例新疆籍静脉药者均感染了HIV-1,其中有2例E亚型,其余均为C亚型。结论:静脉吸毒者主要感染HIV-1C亚型,我国HIV-1主要流行株可能已经发生变化。 相似文献
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Fetal erythropoiesis in steel mutant mice. III. Defect in differentiation from BFU-E to CFU-E during early development 总被引:5,自引:1,他引:5
Erythroid progenitor cells in +/+ and Sl/Sld fetal livers manifested as burst-forming units-erythroid (BFU-E) and colony-forming units- erythroid (CFU-E) were assayed in vitro during early development. The proportion of BFU-E was higher as mutant than in normal fetal livers. On the other hand, the proportion of CFU-E was less in the mutant than in the normal. These results suggest that the defect in Sl/Sld fetal hepatic erythropoiesis is expressed at the steps of differentiation that effect the transition from BFU-E to CFU-E. 相似文献
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Fautrel B Adam V St-Pierre Y Joseph L Clarke AE Penrod JR 《The Journal of rheumatology》2002,29(11):2435-2441
OBJECTIVE: Arthritis or rheumatism (A/R) often leads patients to experiment with complementary and alternative medicine (CAM); we investigated the factors associated with use of CAM. METHODS: The source of the data is the cross sectional household component of the 1996-97 National Population Health Survey of the health status and behaviors of Canadians. The survey sample is based on 66,000 persons aged 20 years and older, representing 21 million adults. Cross tabulations were used to estimate the percentage of adults with A/R who used CAM. Multivariate logistic regression was used to identify those characteristics associated with the use of CAM in the year preceding the survey. RESULTS: In 1996-97, among the 3.3 million Canadian adults aged 20 years or older who self-reported arthritis, 22% utilized CAM in the past year. CAM users tended to be younger and with higher education and household income. They reported more pain, consumed more analgesics, and tended to be more depressed. The coexistence of back or bowel disorders, cancer, sinusitis, or food allergies with arthritis was also related to CAM use. Moreover, CAM users also used more traditional health resources. CONCLUSION: Our results indicate that patients with A/R consulting CAM providers self-report more intense symptoms than nonusers and often have other chronic conditions. They do not seem to reject the traditional health care system, but supplement it with CAM, possibly to fulfill needs insufficiently satisfied by traditional health care providers. 相似文献
90.
Role of selectins in the triggering, growth, and dissemination of T-lymphoma cells: implication of L-selectin in the growth of thymic lymphoma 总被引:1,自引:0,他引:1
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We previously showed that intercellular adhesion molecule-1 (ICAM-1) expression by the host is essential for lymphoma dissemination. Because selectins usually act in a coordinated fashion with ICAM-1 in the recruitment of circulating normal cells, we investigated their implication in lymphomagenesis and metastasis. Using selectin-deficient mice, we found that though the absence of E-, P-, or L-selectins did not affect the triggering of radiation-induced thymic lymphoma, the absence of L-selectin on lymphoma cells reduced their capacity to grow in the thymus. This defect, however, was overcome by altering the integrity of the L-selectin-mediated interactions in the thymus, as shown in L-selectin-deficient mice and by adoptive transfer experiments. We also found that lack of selectin expression by the host significantly delayed the dissemination of lymphomas to peripheral tissues. This resistance of selectin-deficient mice to lymphoma metastasis was dependent on the intrinsic properties of lymphoma cells because highly tumorigenic variants were insensitive to the absence of selectins. Observations that lymphoma cells disseminate with the same efficiency in normal and selectin-deficient mice suggest that selectins exert their influence at the posthoming stage of metastasis, as does ICAM-1. These results provide definitive evidence that selectins play a significant role at different steps of T-cell lymphoma development. 相似文献