首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
一氧化氮(NO)在体内的传递并非以往认为的随机弥散,而是与血红蛋白(Hb)β亚单位中半胱氨酸的硫醇基(巯基)或其他含巯基化合物相结合,形成亚硝基硫醇(SNOs)。SNOs既具备NO的生物活性又保持其稳定性。SNOs从细胞外进入到胞质的途径是通过酶促反应,而从红细胞输出则经阴离子交换蛋白转运。在缺氧情况下,SNOs对呼吸的调控包括:Hb在肺部的氧合作用,将氧输送到组织和在脑干孤束核调控中枢性呼吸。  相似文献   

2.
动物细胞培养反应器氧传递速率的研究   总被引:4,自引:1,他引:3  
本文系统研究了具有笼式通气搅拌装置的CellCul-20A动物细胞培养反应器的氧传递规律,考察了温度、转速、通气速率、丝网及消泡腔对氧传递速率的影响。实验结果表明,通气速率对kLa有显著影响,消泡腔对kLa有不利作用。根据实验数据,建立了表面通气、深层通气的氧传递关联式。  相似文献   

3.
黄瓜细胞中水杨酸的信号传递研究   总被引:14,自引:0,他引:14  
应用放射性标记、薄层层析和阴离子交换柱层析技术,证明黄瓜(CucumissativaL.)细胞中存在肌醇脂质信使系统,并且水杨酸(SA)能够促进肌醇磷脂代谢,激活磷脂酶C(PLC),促进磷脂酰肌醇降解,导致第二信使肌醇1,4,5三磷酸(IP3)和双酰甘油(DAG)含量增加,表明SA信号传递有可能通过肌醇脂质信使系统的介导来完成。SA的生理功能尤其在诱导植物抗病性中的作用很可能是通过肌醇脂质信使系统介导的。  相似文献   

4.
5.
应用蚜虫吻针穿刺技术研究植物的电波传递   总被引:3,自引:0,他引:3  
目前认为,植物体内的信息传递有三种方式,即水信号、化学信号和电信号[1]。电信号在快速及长距离信息传递中起着重要的作用。现已证明:植物体内的电波传递是一个普遍现象,它能调节许多生理反应[1,2,6,7]。如伸长生长、呼吸作用、水分吸收、韧皮部物质外卸、膨压下降及光合与蒸腾作用的改变、蛋白酶抑制剂基因的激活、气体交换等。在逆境生理的研究中,电信号的作用尤为突出,因为它能迅速地将一个部位感受的信息及时传递到其他部位[4]。目前,在电生理学研究中常使用胞外电极来检测离体组织或整体植株的电波传递;使用胞内电极检测单个…  相似文献   

6.
大白鼠上丘脑片深层部突触传递和LTP的研究   总被引:2,自引:2,他引:0  
在大白鼠上丘脑片深层部的中层或深层给电刺激、分别在径向对应的深层或中层,记录到诱发的突触后场电位.以100Hz、1秒的强直刺激首次在上丘的深层部引出了长时程突触增强(LTP).N-甲基-D-天冬氨酸(NMDA)受体的选择性拮抗剂2-氨基-5-磷酸戊酸盐(APV)对LTP的阻断效应表明,NMDA受体不仅对上丘深层部LTP的产生有作用.而且也与LTP的维持有关.突触后场电位的幅度受APV或兴奋性氨基酸受体的非选择性拮抗剂犬尿喹啉酸(KYNA)的作用而减小,受γ-氨基丁酸(GABA)A型受体的选择性拮抗剂荷包牡丹碱(Bicu)的作用而增加,表明谷氨酸能神经递质在上丘深层部的兴奋性突触传递中起着重要作用,并且这些突触传递也受到GABA能抑制性突触的调节.  相似文献   

7.
双歧杆菌粘附体外肠上皮细胞的钙信号传递的研究   总被引:5,自引:1,他引:4  
本文采用钙荧光探剂 Fluo—3/AM染色法,定量研究了双歧杆菌1027株、肠致病性大肠杆菌(EPEC)对体外肠上皮细胞Lovo细胞株粘附的钙信号传递机制。结果表明,双歧杆菌1027株粘附可引起Lovo细胞内Ca~+2随时间延长而梯度升高,但双歧杆菌1027株的作用远不如EPEC明显。同时发现双歧杆菌粘附引起Lovo。细胞内Ca~2+升高主要源于细胞外Ca~2+内流所致,这与EPEC粘附引起宿主细胞内Ca~2+升高主要源于细胞内Ca~2+储池的Ca~2+释放不同。EPEC粘附引起宿主细胞内Ca~2+大幅度升高是其致病的重要信号传递基础;而双歧杆菌粘附仅引起宿主细胞内Ca~2+轻度升高,可能是其作为生理性细菌与肠上皮细胞和谐共生的信号传递基础。  相似文献   

8.
白纹伊蚊和埃及伊蚊经卵传递登革病毒的研究   总被引:11,自引:0,他引:11  
白纹伊蚊和埃及伊蚊通过吸食病毒液或叮吸有病毒血症的小鸡血后,能感染登革1-4型病毒,并能在蚊体内增殖,对感染雌蚊了1和子2代幼虫,雌性或雄性成虫4559只,分101批进行了病毒检测,白纹伊蚊子1代的批阳性率;登革1型为10%(1/10)2型为22.22%(2/9)3型为33.33%(4/12),4型为28.95%(11/38)登革1~4型的最低子代感染率依次主国0.20%,0.71%,0.70%和  相似文献   

9.
三叶草体内磷通过菌丝桥向黑麦草的传递研究   总被引:11,自引:3,他引:11  
应用5室分隔法研究了供体三叶草体内的32P通过菌丝桥向受体黑麦草的传递作用。结果表明,菌根侵染供体三叶草根系之后,根外菌丝可穿过中室到达受体植株根室而再度侵染受体黑麦草的根系,从而形成三叶草-黑麦草根系之间的菌丝桥;供体三叶草体内的32P可通过根间菌丝桥传递给受体黑麦草,32P的传递量随受体植株施磷水平的提高而降低.  相似文献   

10.
低强度He-Ne激光对神经干传递兴奋作用的研究廖映高晓玲(四川教育学院生物系,成都:610041)彭秀琼霍莉琼(华西医科大学附二院,成都:610041)(德阳市第一人民医院激光科,618000)关键词激光神经干传递蟾蜍StudiesontheLow...  相似文献   

11.
牛脾转移因子的提取工艺研究   总被引:2,自引:0,他引:2  
目的:比较从牛脾中提取活性TF的不同方法。方法:分别利用Lawrence--透析法、Lawrence-超滤法、超离心-超滤法提取,再以蛋白反应、红外及紫外扫描予以鉴定比较。结果:Lawrence-超滤法和超离心-超滤法效果较好。结论:工业化生产中应采用Lawrence-超滤法。  相似文献   

12.
Using a blood cell separator, lymphocytes were collected from otherwise healthy convalescents suffering from herpetic infections. A specific anti-herpes dialysate (AH-DLE) was prepared from the lymphocytes, using standard procedures. Patients with recurrent herpetic infections were treated with a single dose of the dialysate, at the initial signs of herpetic infection (group A), with two doses (group B) or with three doses (group C). A total number of 37 patients (29 women, 8 men, age range 15–73 years) were treated. No improvement was observed in 7 patients (18.9%), whilst 7 patients did not manifest any exacerbation of their herpetic infection in the course of the one-year follow-up. The remaining 62.2% of the patients showed a marked improvement: decrease of the frequency and/or duration or relapses. Before AH-DLE administration, the mean number of herpes relapses in this group of patients was 12 p.a.. After therapy, the number of relapses decreased to 3.5 p.a.. No statistically significant difference was observed between groups A and B. The least favourable results were registered in group C. However, this group included 6 female patients extremely resistant to the previously therapeutic attempts, including inosiplex, non-specific DLE or acyclovir. Thus, even in this group, the therapy was successful in 50% of the patients.  相似文献   

13.
碳同位素技术在森林生态系统碳循环研究中的应用   总被引:4,自引:3,他引:4  
郑兴波  张岩  顾广虹 《生态学杂志》2005,24(11):1334-1338
碳同位素技术对碳素在生态系统中的迁移动态具有很好的示踪作用,在生态学各领域研究中应用广泛。土壤、大气、植物是森林生态系统的重要碳库,植物是大气和土壤交换碳元素的重要介质。本文简要总结了碳同位素技术在研究碳元素在植物体内以及植物、土壤、大气碳库之间的迁移规律和生态学过程中的应用,展望了该技术在森林界面学中的应用前景。  相似文献   

14.
Preliminary observations using HIV-specific transfer factor in AIDS   总被引:2,自引:0,他引:2  
Twenty five HIV-1-infected patients, at various stages (CDC II, III and IV) were treated orally with HIV-1-specific transfer factor (TF) for periods varying from 60 to 1870 days. All patients were receiving antiviral treatments in association with TF. The number of lymphocytes, CD4 and CD8 subsets were followed and showed no statistically significant variations. In 11/25 patients the number of lymphocytes increased, whilst in 11/25 decreased; similarly an increase of the CD4 lymphocytes was observed in 11/25 patients and of the CD8 lymphocytes in 15/25. Clinical improvement or a stabilized clinical condition was noticed in 20/25 patients, whilst a deterioration was seen in 5/25. In 12/14 anergic patients, daily TF administration restored delayed type hypersensitivity to recall antigens within 60 days. These preliminary observations suggest that oral HIV-specific TF administration, in association with antiviral drugs, is well tolerated and seems beneficial to AIDS patients, thus warranting further investigation.  相似文献   

15.
1. Transfer of dansyl-platelet factor 4 complexed with a series of glycosaminoglycans to heparin has been detected and studied by measuring changes in the anisotropy of the dansyl fluorescence. The protein was most easily transferred from chondroitin sulphate and least easily from heparan sulphaet. 2. The transfer of the dye-labelled protein from its biological chondroitin 4-sulphate proteoglycan carrier to natural and synthetic anionic polymers was similarly followed. The transfer to heparin and dermatan sulphate was shown to be the same whether 3 mM Ca2+ or 8 mM EGTA was present in the solution. 3. The shapes of the binding curves of the dansyl-factor to the polymers have been compared at I = 0.4 M. 4. The observed changes in anisotropy of dye fluorescence have been correlated with the charge density and the stereochemistry of the charged groups of the natural polymers. Large complexes are observed with polymers of high negative charge/weight ratios. Less charged polymers containing disaccharide units of iduronic acid and glucosamine N-sulphate will also form large complexes at I = 0.15 M. 5. It is demonstrated that the release of a platelet factor 4 proteoglycan complex in vivo would result in the transfer of the protein to heparin, moderate quantities of either dermatan or heparan sulphates would not prevent this transfer.  相似文献   

16.
脑源性神经营养因子研究进展   总被引:10,自引:0,他引:10  
脑源性神经营养因子是一种小分子二聚体蛋白质,在结构上与神经生长因子相关。对中枢神经系统的多种类型神经元的生长、发育、分化、维护和再生部具有重要作用,对于治疗运动神经元病变以及神经系统迟行性疾病有显疗效。本对其细胞与分子生物学特征、生物学功能进行阐述。  相似文献   

17.
Ciliary neurotrophic factor (CNTF) is known as an important factor in the regulation of retinal cell growth. We used both recombinant CNTF and an adenovirus carrying the CNTF gene to regulate retinal photoreceptor expression in a retinal degenerative animal, Royal College of Surgeons (RCS) rats. Cells in the outer nuclear layer of the retinae from recombinant-CNTF-treated, adenoviral-CNTF-treated, saline-operated, and contralateral untreated preparations were examined for those exhibiting CNTF photoreceptor protective effects. Cell apoptosis in the outer nuclear layer of the retinae was also detected. It was found that CNTF had a potent effect on delaying the photoreceptor degeneration process in RCS rats. Furthermore, adenovirus CNTF gene transfer was proven to be better at rescuing photoreceptors than that when using recombinant CNTF, since adenoviral CNTF prolonged the photoreceptor protection effect. The function of the photoreceptors was also examined by taking electroretinograms of different animals. Adenoviral-CNTF-treated eyes showed better retinal function than did the contralateral control eyes. This study indicates that adenoviral CNTF effectively rescues degenerating photoreceptors in RCS rats.S.-P.H. and P.-K.L. contributed equally to this work.  相似文献   

18.
Recurrent ocular herpes is an insoluble problem for the clinician. As cellular immunity plays an important role in controlling herpes relapses, and other studies have shown the efficacy of HSV-specific transfer factor (TF) for the treatment of herpes patients, an open clinical trial was undertaken in 134 patients (71 keratitis, 29 kerato-uveitis, 34 uveitis) suffering from recurrent ocular herpetic infections. The mean duration of the treatment was 358 days, and the entire follow-up period 189121 before, and 64062 days after TF treatment. The cell-mediated immune response to the viral antigens, evaluated by the lymphocyte stimulation test (LST) and the leucocyte migration test (LMT) (P<0.001), was significantly increased by the TF treatment. The total number of relapses was decreased significantly during/after TF treatment, dropping from 832 before, to 89 after treatment, whereas the cumulative relapse index (RI) dropped, during the same period, from 13.2 to 4.17 (P<0.0001). No side effects were observed. It is concluded that patients with relapsing ocular herpes can benefit from treatment with HSV-specific TF.  相似文献   

19.
Transfer Factor (TF) was used in a placebo controlled pilot study of 20 patients with chronic fatigue syndrome (CFS). Efficacy of the treatment was evaluated by clinical monitoring and testing for antibodies to Epstein-Barr virus (EBV) and human herpes virus-6 (HHV-6). Of the 20 patients in the placebo-controlled trial, improvement was observed in 12 patients, generally within 3-6 weeks of beginning treatment. Herpes virus serology seldom correlated with clinical response. This study provided experience with oral TF, useful in designing a larger placebo-controlled clinical trial.  相似文献   

20.
裴崇强  金鸣 《生物磁学》2009,(20):3972-3975,3985
NF-κB信号转导途径与肺部的炎症性病变有密切关系,以此信号通路为作用靶点的抗炎治疗是近年研究的热点。本文综述了肺部各种细胞内NF-κB活化的作用以及应用NF-κB抑制剂治疗肺部疾病的研究进展,为急性肺损伤等肺部炎症的药物治疗研究提供参考依据。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号