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51.
52.
M R Yi M H Shin M H Leem J S Ryu M H Ahn D Y Min 《The Korean journal of parasitology》1990,28(1):25-30
The direct wet mount examination of vaginal secretion, widely applied for the diagnosis of Trichomonas vaginalis infection in woman patients, is rapid and economical, however, the sensitivity of this technique is not so high. In this study enzyme-linked immunosorbent assay (ELISA) was employed for the detection of serum anti-T. vaginalis IgG and IgM antibodies from 30 vaginal trichomoniasis patients and 30 non-infected healthy persons. The results were as follows: 1. Serum ELISA-IgG value was 0.37 +/- 0.134 (Mean +/- S.D.) in vaginal trichomoniasis patients and 0.21 +/- 0.054 in healthy controls (p less than 0.005), and the sensitivity and specificity of ELISA for serum IgG antibody were 70.0% and 96.7%, respectively. 2. Serum ELISA-IgM value was 0.33 +/- 0.177 (Mean +/- S.D.) in vaginal trichomoniasis patients and 0.11 +/- 0.051 in healthy controls (p less than 0.005), and the sensitivity and specificity of ELISA for serum IgM antibody were 70.0% and 96.7%, respectively. 3. The ELISA-IgG values showed a significant correlation with ELISA-IgM values (r = 0.77, p less than 0.005). With above results, it is assumed that ELISA is a reliable method for the diagnosis of T. vaginalis infection and simultaneous measurement of serum IgG and IgM with this technique is recommended. 相似文献
53.
This study was aimed to observe the direct and lymphokine-activated cell mediated cytotoxic effects against Trichomonas vaginalis by mouse peritoneal macrophages. Cytotoxicity was measured as release of 3H-thymidine from prelabeled protozoa, and tested in U-bottom microtiter plates. A 0.1 ml suspension of labeled protozoa (2 x 10(5)/ml) was placed in each well, followed by 0.1 ml of a suspension containing increasing numbers of peritoneal cells. After a 24 hr incubation at 37 degrees C, 0.1 ml of the supernatant was collected and counted in liquid scintillation counter. Mouse peritoneal macrophages had appreciable level of spontaneous cytotoxicity against T. vaginalis at the effector to target cell ratios from 5:1 to 50:1. Treatment of macrophages with lymphokine, produced by PHA-stimulated spleen cells, increased the cytotoxicity in comparison with resident macrophages against T. vaginalis. The degree of macrophage activation for the killing was not dependent upon the lymphokine concentration. Peritoneal cells adherent to plastic displayed significant levels of cytotoxicity against T. vaginalis. This study indicates that mouse peritoneal macrophages are spontaneously cytotoxic for T. vaginalis and lymphokine increases the cytotoxicity by activating macrophages to kill T. vaginalis. 相似文献
54.
Paragonimus westermani is a tissue migrating parasite in the early stage until arriving at lung, and most of the parasites spend their life spans there. Considerable immune responses including activation of macrophages are taken place during the residence of parasites in the host. However, concerning the immunologic defense mechanisms of the host against this parasite, only a few document is available so far. In this study, the cytotoxic effect of peritoneal macrophages under the presence of antibody and/or complement against metacercariae of P. westermani was investigated in vitro. Metacercariae were collected from the crayfish, Cambaroides similis and hatched out in Tyrode solution (pH 7.4). Plastic adherent cells from normal or infected rat (Wistar) peritoneal exudates were used as experimental macrophages. Polyclonal antibodies were obtained from infected rats and a cat. Cat IgG was fractioned with ion exchange chromatography. Fresh rabbit complement was used according to experimental scheme. Various combinations of peritoneal macrophages, normal or infected rat serum, complement and cat IgG were incubated at 36 degrees C in 5% CO2 incubator for 6, 14, 24 and 48 hours. The results obtained were as follows: 1. P. westermani infection activated peritoneal macrophages non-specifically and this activation induced increases of cell adherence and cytotoxicity on metacercariae. 2. In the presence of infected rat serum the antibody-dependent cell-mediated cytotoxicity of peritoneal macrophages on metacercariae was significantly increased and showed a peak at 6-hour incubation. But the cytotoxic effect was markedly reduced after inactivation of complement and heat-labile IgE antibody by the heating of infected serum at 56 degrees C for 30 minutes. 3. The highest cytotoxic effect (100%) of concomitant incubation with IgG and complement showed 24 hours after incubation, although cell adherence was relatively low at 6-hour incubation and 0% at 24-hour incubation. 4. Coordinative functions of complement with serum and IgG were effective in cell adherence and in cytotoxicity, but it is not clear the independent role of complement on the macrophage-mediated cytotoxicity in this study. With these results it is assumed that P. westermani infection can induce the non-specific activation of peritoneal macrophages, and serum antibodies including IgE antibody might enhance the cytotoxicity by macrophages. 相似文献
55.
56.
菘蓝多倍体育种的研究 总被引:39,自引:0,他引:39
本文报道药用植物菘蓝(Isatis indigotica Foft.)同源四倍体的诱发、鉴定、选育的研究。用0.05-0.5%浓度的秋水仙碱水溶液处理萌发的种子,或用0.05-0.3%浓度的此溶液处理幼苗的生长点,均可以获得四倍体植株。最适宜的处理时间为6-12小时。除用直接的细胞学技术鉴定多倍体植株外,一些重要的间接鉴定特征,如叶表皮保卫细胞中叶绿体数,花粉沟数可作为鉴定本种多倍体植株的可靠指标。比较了四倍体植株和二倍体亲本的生物学特性。经过数代选育,获得了性状稳定、繁殖力正常、根与叶中活性成分均有较大幅度提高、生产性能良好的品系。 相似文献
57.
水葫芦根部分泌物对若干细菌作用的研究 总被引:13,自引:1,他引:12
生态系统中各种生物种群之间的关系是错综复杂的,而物种之间的关系又直接或间接地影响着生态系统的功能。水葫芦对藻类的克制效应,以及城市富营养化水域的生物治理 相似文献
58.
F_(IO_2)(吸入气氧浓度)为12.35、9.87及7.7l%,分别吸入10、8及5min时,心功能呈代偿性增强改变。F_(IO_2)为9.37%、吸入20min时心功能的变化趋势与9.87%8min时仍基本相同。继发性缺二氧化碳对缺氧引起的心功能代偿性增强,在一定程度上起抵消作用。F_(IO_2)为9.87%时的缺氧程度约相当于18km高空加压供氧总压值为15.3kPa(115mmHg)时的缺氧。单纯从缺氧因素考虑,将总压值由常用的17.3kPa(130mmHg)降低为15.3kPa是可允许的。 相似文献
59.
种间竞争的一个新的数学模型—对经典的Lotka—Vol—terra竞争方程的扩充 总被引:2,自引:1,他引:1
本文根据营养动力学理论,建立了一类种间竞争的新的数学模型:它是单种群增长的Cui-Lawson模型,在种间竞争上的推广。新的种间竞争模型克服了经典的种间竞争的Lotka-Volteira方程的局限与不足,具有更广泛和复杂的行为,并在特殊条件下以Lotka-Volterra竞争方程为其特例。因此,新的种间竞争的数学模型是更一般的解释性模型,是对经典的Lotka-Voterra竞争方程的扩充。 相似文献
60.
厚朴类有效成分的含量测定及高效液相色谱图 总被引:9,自引:0,他引:9
用高效液相色谱法对我国木兰科植物“厚朴类”中的酚类和季胺碱类作了定性和定量分析,并提供色谱图,结果表明不同产地的“厚朴”,图谱相同,仅含量有差别,但不同种的“厚朴”,色谱图不同.此结果可作为评价“厚朴类“药材质量和鉴别的方法.根据各类厚朴有效成分的存在,有一定的规律,为木兰科植物化学分类提供了有价值的资料。 相似文献