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41.
42.
螺旋神经节神经元原代培养及其免疫细胞化学鉴定 总被引:8,自引:1,他引:7
孙建军 《中华耳鼻咽喉科杂志》1998,33(4):196-198
目的 建立成体哺乳动物耳蜗螺旋神经节神经元(SGN)体外培养的细胞模型。方法 对出生后7d的Wistar大鼠的螺旋神经节细胞进行解离与分散培养。用荧光显微镜与倒置相差显微镜观察原代培养SGN细胞的活力以及生长与分化过程。应用链霉卵白素过氧化物酶(SP)方法和抗神经丝蛋白单克隆抗体(NFP-McAb)对SGN进行免疫细胞化学染色鉴定。结果 幼龄Wistar大鼠的SGN在体外条件下,可良好存活并有正常 相似文献
43.
神经肽Y(NPY)是广泛分布于中枢神经系统和外周神经各部位的神经肽类物质。本实验观察NPY在体外对几种免疫细胞活性的直接作用。结果表明,NPY对小鼠T淋巴细胞丝裂原反应性和NK细胞的杀伤活性均无明显影响(P>0.05),对巨噬细胞分泌溶菌酶有明显抑制作用(P<0.05);而对B淋巴细胞丝裂原反应性则有明显的促进作用(P<0.05)。上述结果提示,NPY对部分免疫细胞功能的影响因细胞种类而异。 相似文献
44.
Summary. Clones of an African cassava mosaic virus isolate originating from Nigeria (ACMV-NOg) were shown to be infectious to cassava by biolistic inoculation. The production of pseudorecombinants between ACMV-NOg and clones of an ACMV isolate originating from Kenya (ACMV-K) indicated that the lack of infectivity of ACMV-K to cassava
was due to defect(s) in the DNA B genomic component; this component encodes two proteins involved in cell-to-cell movement.
This is the first demonstration of infectivity of a cloned geminivirus to cassava and conclusively proves that ACMV is the
causative agent of cassava mosaic disease. The potential uses of infectious ACMV clones and the means by which to introduce
them into cassava are discussed.
Received January 18, 1998 Accepted May 27, 1998 相似文献
45.
Rh血型不合新生儿溶血病检测方法及应用 总被引:3,自引:0,他引:3
产前检测Rh,D因子及抗人球蛋白(coombs)试验是必要的。测定Rh,D因子及抗D滴度使用木瓜酶方法。通过对11261例孕妇常规检查Rh,D因子,发现D阴性74例。Rh,D阴性妇女占6.5‰。22例Rh,D阴性的孕妇所分娩的新生儿均为Rh,D阳性。其中2例孕妇血清抗D滴度为1∶32,病情严重,宫内输血无效,胎死宫内。初产妇13例,占59%。活产20例,存活率90%。Rh因子及抗人球蛋白试验方法简便、易行,一般医院均可进行。对有流产史、输血史的孕妇检查Rh因子是十分必要的。在有条件的医院,对Rh,D阴性的产妇分娩Rh,D阳性的新生儿之后,产妇应预防性注射抗D免疫球蛋白 相似文献
46.
47.
Y Matsuhima J S Liu E Tajika K Nagai Y Koshiishi K Oho Y Hayata 《Nihon Geka Gakkai zasshi》1990,91(1):23-28
Sixteen malignant tumors of soft tissue (15 cases) were treated with low voltage direct current (DC therapy) with or without systemic chemotherapy. Two platinum or stainless steel electrodes were placed in the tumor and around 10 volts of direct current was passed for 1 hour. In cases in which chemotherapy was performed, single or combined anticancer agents consisted of ADM and BLM were administered simultaneously with DC therapy by systemic route. Ten cases (11 tumors) out of 15 cases received no other local treatment. Histological examination was performed in 6 of 11 lesions, and in all lesions pathological therapeutic effects were recognized. Decrease in tumor size was observed in 9 lesions. In 2 cases the tumors disappeared completely after DC therapy only. In one case receiving DC therapy with chemotherapy, the tumor decreased dramatically and became resectable. Main complications were slight pain during treatment and slight fever after treatment, but special treatment for these complications was not necessary. Our results suggested that DC therapy with or without systemic chemotherapy was useful for local control of malignant tumors. And also if DC therapy had been performed simultaneously with chemotherapy the therapeutic effects seemed to be more emphasized than single use of these therapies. 相似文献
48.
The objective of this study was to determine whether the development of tolerance to CP 55,940, a potent cannabinoid agonist, was due to changes in the receptor or second messenger system. ICR mice treated with CP 55,940 (2 mg/kg) twice a day for 6 and one-half days developed a high degree of tolerance to the pharmacological effects of CP 55,940. The ability of CP 55,940 to produce motor hypoactivity, hypothermia and immobility was reduced 163-, 97- and 19-fold, respectively. Evaluation of 3H-CP 55,940 binding to rat brain membranes indicated no difference in receptor affinity between the vehicle- and CP 55,940-treated animals. However, these binding studies revealed a 50% decrease in receptor number in the cerebellum of the CP 55,940-tolerant mice. Although cAMP is generally considered to be the second messenger for cannabinoid receptors, little difference was observed in the inhibitory effects of CP 55,940 on adenylyl cyclase activity in cerebellum between vehicle and drug-treated mice. However, there was an increase in receptor mRNA which suggests a compensation for receptor loss. There are several possible explanations for these results. There may be sufficient spare receptors such that CP 55,940-tolerant mice are capable of producing a maximal effect on the second messenger system. On the other hand, one could conclude that cannabinoid receptor down-regulation does not account for the development of tolerance to all of the effects of CP 55,940 in mice. 相似文献
49.
本文用同时记录两相邻空肠段的收缩活动来观察经10Gyγ线照射后小肠运动的变化,以了解照射后是否出现逆蠕动,以便进一步分析肠套叠形成的原因.结果表明,照射后两相邻肠段出现强度不一的收缩活动,并且可以产生逆蠕动;但是这种逆蠕动发生的机率是不大的.本实验未观察到逆蠕动发生的规律性.因此,逆蠕动的产生可能是照射后发生肠套叠的部分原因. 相似文献
50.