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1.
黄鳝活体内制备SCD法和SCE频率的测定   总被引:1,自引:0,他引:1  
哺乳类活体内制备姊妹染色单体分化染色(Sister Chromatid Differentiation,SCD)法国内外已有不少的报道,至于鱼类,曾有学者报道采用肾细胞培养制备 SCD。本实验对黄鳝活体内制备 SCD 法进行了探索,并对其姊妹染色单体交换(Sister Chromatid Exchange,SCE)频率作了测定。  相似文献   

2.
CFSE标记技术及其在细胞研究中的应用进展   总被引:3,自引:0,他引:3  
近年来活体染料CFSE已被广泛应用,其作用机制也逐渐阐明。它不仅应用于细胞增殖的体外实验,也可用于追踪细胞在体内的分裂增殖过程,为细胞免疫和细胞生物学研究开辟了一条新的有效途径。本文综述了活体染料CFSE的性质、工作原理及应用。  相似文献   

3.
活体电穿孔法基因导入技术   总被引:2,自引:0,他引:2  
活体电穿孔法(invivoelectroporation)可将外源基因有效导入靶组织或器官,导入效率较高,并且可在多种组织器官上应用。近年来活体电穿孔法用于转基因研究的报道不断增多,在基因治疗方面的优势也日趋显著,是一种很好的活体基因导入方法 。  相似文献   

4.
动物活体环境下单细胞的光操控对于研究细胞的结构和功能,细胞与组织之间的相互作用,以及细胞病变机理、血栓形成机制和肿瘤细胞迁移等生物医学问题具有重要意义。2013年,光镊技术首次应用于活体动物内单细胞的捕获和操控,开辟了活体动物内光学操控新领域。本文就该领域涉及的活体操控技术及近来取得的重要研究进展进行概述,简要分析了实现深度组织内细胞操控所遇到的技术瓶颈并讨论了解决方案。  相似文献   

5.
目的:建立大鼠高脂血症模型,观察活体内高脂刺激下血管平滑肌细胞内wnt/-catenin信号通路的激活及血管平滑肌细胞增殖情况,探讨活体内wnt/-catenin信号通路的激活与血管平滑肌细胞增殖的关系。方法:以雄性SD大鼠为研究对象,体重200~250g。通过饲以高脂饲料建立高脂血症模型。12周后处死大鼠,获取主动脉。苏丹III染色检测血管壁粥样硬化病变,HE染色、透射电镜检测血管平滑肌细胞增殖及表型变化,实时定量RT-PCR及Western Blot检测β-catenin、T cell factor 4(TCF-4)、cyclin D1的变化。结果:通过3个月的高脂饮食饲养,成功建立大鼠高脂血症模型,但大鼠主动脉壁粥样硬化病变不明显。高脂刺激下,mRNA及蛋白水平的β-catenin、TCF-4、cyclin D1表达均增加;同时血管壁内平滑肌细胞增殖增加、表型由收缩型向合成型变化。结论:高脂饮食可以成功建立大鼠高脂血症模型,但由于大鼠本身的代谢特点,不容易出现动脉粥样硬化斑块。Wnt/-catenin信号通路在高脂情况下被激活,同时平滑肌细胞增殖增加、表型改变,提示wnt/-catenin信号通路的激活与平滑肌细胞增殖之间存在联系。  相似文献   

6.
在9月份出版的《自然·化学生物学》中,研究人员首次报道了在活体脊椎动物中分析组织功能的高通量分析法。这是一种对活体组织功能监测的有力工具,可观察药物在活体中的效果。然而,评估药物作用于单个组织效果的需求仍对自动高通量鉴  相似文献   

7.
动态     
东京大学医科学研究所细菌感染研究部的土屋辉昌发现了贫血状态的小鼠肝脏能诱导结合于造血因子EPO基因上游部位的蛋白,在4月京都召开的日本血液学会上发表这一结果。EPO是促进红细胞增殖的细胞激肽之一。该蛋白在肾脏内处于低氧状态时刺激EPO基因的转录,可促进红细胞的恢复。为研制在活体内使用的氧传感器开辟了途径。据土屋介绍在小鼠正常状态下的肾脏中至少存在着3种EPO上游基因结合蛋白,但是,苯肼会引起  相似文献   

8.
HLA-G参与骨髓间充质干细胞的抑制作用机制探讨   总被引:1,自引:0,他引:1  
目的:探讨人骨髓间充质干细胞(MSC)在活体肾移植供受者间的混合淋巴细胞培养(MLR)中的作用机制,证明人白细胞抗原(HLA)-Ⅰ类分子HLA-G参与了MSC的免疫调节作用。方法:从人骨髓中分离培养MSC,采用形态学观察及流式细胞术分析鉴定后,加入活体肾移植供受者间的MLR,观察MSC的HLA-G表达及对T细胞增殖的影响,淋巴细胞增殖实验采用MTT法。结果:MSC细胞表面和胞浆内均表达HLA-G,流式细胞术分析细胞表面HLA-G平均表达率为37.3%,胞浆内HLA-G平均表达率为65.1%,ELISA法检测细胞培养上清中可溶性HLA-G含量为18.9ng/mL。将MSC和培养上清液加入活体肾移植供受者间的MLR体系中,均使得T细胞抑制率增高;而加入HLA-G特异性抗体,MSC的抑制率降低。结论:MSC表面和胞浆内均有HLA-G表达,在其培养上清中检测到由MSC分泌的可溶性HLA-G5;MSC表达和分泌的HLA-G是其发挥抑制功能的关键因素之一。为MSC在预防器官移植术后排斥反应的临床应用提供了理论依据。  相似文献   

9.
1 引  言随着中华绒螯蟹 (Eriocheirsinensis)人工育苗规模的扩大 ,生产实践中有关小型甲壳类活体饵料投喂问题受到生产者和一些学者的重视[1,3 ,4] ,本研究分析中华绒螯蟹幼体消化道内甲壳质消化细菌 ,试图从该方面探讨中华绒螯蟹幼体与甲壳类活体饵料动物之间的关系 .有关水生动物消化道内甲壳质消化细菌 ,曾在鱼胃中有发现 .中华绒螯蟹消化道内微生物的研究未见有报道 ,我们对中华绒螯蟹 氵蚤Ⅰ大眼幼体消化道内甲壳质消化细菌进行了分离筛选 ,以探讨其消化机理 ,并为人工育苗生产中合理选择时机投喂卤虫 (Artemiasalina)、枝角类等…  相似文献   

10.
幽门螺杆菌表面抗原免疫保护作用的体外与活体研究   总被引:6,自引:1,他引:6  
目的:调查幽门螺杆菌(Hp)几种表面蛋白体外对T细胞增殖的影响和在小鼠体内的免疫保护作用。方法:评价Hp全菌抗原、尿原酶(Urease)、黏附素(hpaA)、外膜蛋白25(Hop25)和38(Hop38)对人外周血T细胞及小鼠CD4^ T细胞增殖的影响;与佐剂合用,评价上述重组蛋白对小鼠Hp感染的免疫预防作用。结果:Urease和Hop25可刺激人及鼠T细胞增殖,hapA只能刺激Hp^ PBL增殖,而Hop38则有毒性作用;Hop25和Hop38均可产生60%的完全保护,hpaA可产生100%的部分保护即降低细菌定植密度,而Urease只能产生40%的部分保护。结论:外膜蛋白可能是一组高效的Hp疫苗免疫原;其长期免疫效果及对T细胞功能的活体调节作用尚需进一步评价。国际上尚未见相关报道。  相似文献   

11.
谢仁敷  袁淑雯 《生理学报》1989,41(2):172-178
小鼠骨髓细胞体外液体培养,形成基质细胞层(SL),能影响在其上培养的粒系祖细胞(CFU-GM)增殖。培养1周,SL明显抑制CFU-GM,约为对照的50%;2周,SL之抑制减弱,3周,SL则促进CFU-GM,约达对照140%。在CFU-GM培养体系中加入消炎痛(1×10~(-7)mol/L),却使1周SL上CFU-GM增加,2周SL上者增加更显著,第3周者则无明显改变。在CFU-GM培养体系中加入PGE_1(1×10~(-8)mol/L),各周SL上CFU-GM均大为减少。若同时再加消炎痛(2×10~(-7)mol/L),基质层上CFU-GM,1周者上升到约为对照42.6%,2周者则接近对照。而3周者则用消炎痛1×10~(-7)mol/L,即可使CFU-GM产率恢复。说明SL培养1周,能生成一定量PGE,2周时PGE生成减少,3周则几乎为零。故SL影响CFUGM,至少部分地以PGE为中介。  相似文献   

12.
I G Panova  O G Stroeva 《Ontogenez》1978,9(2):179-183
Following the lens removal from the left eye of the newborn rats, animals were obtained with one normal (control) and another microphtalmic eye. The animals were sacrificed on the 2nd, 3rd, 5th, 7th and 9th days of postnatal development after four injections of 3H-thymidine during 19 hrs. The number of labelled nuclei and mono- and binuclear cells in the central zone of the eye fundus was counted on the autographs. After the initial increase of the index of labelled nuclei in the operated eyes (on the 2nd, 3rd and 5th days) it fell below the control level (on the 7th and 9th days). The number of binuclear cells in the operated eyes, as well as in the control, attains on the 5th day 50% of the total number of cells and remains at this level up to the end of the experiment, whereas in the control eyes the number of binuclear cells increases up to 60% on the 7th and 80% on the 9th day. The results obtained have shown that in rats the factors of total eye growth participate in the control of proliferative activity and polyploidization of the pigment epithelium cells in the retina.  相似文献   

13.
电针对脊髓损伤星形胶质细胞增生及其NGF表达的影响   总被引:2,自引:0,他引:2  
目的研究脊髓损伤后电针治疗对星形胶质细胞增生及其内源性神经生长因子(nerve growth factor,NGF)表达的影响.方法选用成年雌性Wistar大鼠,随机分为3组.A组为正常对照组,B组、C组为下胸段脊髓不完全损伤.B组损伤后不治疗,C组损伤后给予督脉电针治疗.损伤后3 d、1 、2或4周应用免疫组化染色分别观察损伤脊髓胶质原纤维酸性蛋白(glial fibroblast acid protein,GFAP)和NGF表达的变化.结果 B组术后3 d,GFAP阳性细胞明显增多, 2周后开始减少,4周时仍有较多的阳性细胞;C组GFAP阳性细胞明显少于B组,1周时达高峰.脊髓损伤后NGF表达呈逐渐增加的趋势.C组NGF的表达明显高于B组,且一直保持在较高水平.NGF阳性细胞大部分与GFAP阳性细胞形态相似.结论电针治疗能减少星形胶质细胞增生,促进内源性NGF的合成,从而创造了有利于神经再生的微环境.  相似文献   

14.
The effect of RBC transfusion and erythropoietin (EPO) on the proliferation of immature erythrocyte progenitors was studied in the spleens of RBC transfused, lethally irradiated mice injected with bone marrow. Transfusion decreased expansion of the progenitors and slowed their proliferation: the mean cycle time as measured by per cent labelled mitosis (PLM) on the third day after injection of bone marrow was 10.7 hr in transfused as compared to 5.6 hr in non-transfused mice. One injection of five units of erythropoietin on day 2 decreased the mean cycle time to 7.3 hr in transfused mice and increased expansion of the progenitor cells. The effects of erythropoietin on cell proliferation were prompt: a significant increase of incorporation of 3H-TdR into DNA occurred within 2 hr of injection. Erythroblasts were absent from the spleens of transfused, irradiated bone marrow injected mice; however, erythroblasts appeared by 72 hr and 48 hr following EPO injection either 2 days or 5 days after transplantation respectively. Increased uptake of radioactive iron in spleen after erythropoietin injection preceded the appearance of erythroblasts by 2 and 1 days when erythropoietin was injected either 2 or 5 days after marrow transplantation respectively. The increase in cellular proliferation induced by erythropoietin in transfused irradiated mice injected with bone marrow equivalent to 0.35 femoral shaft was manifested as an increase of the total DNA content in the spleen by 119 μg (11.9 × 106 cells) within 48 hr of injection. The cellular increment produced by EPO injection on day 5 to mice given 0.05 femoral shaft consisted mainly of undifferentiated mononuclear cells, most of which were labelled, with erythroblasts comprising only one quarter of the increment. Erythropoietin inactivated by mild acid hydrolysis failed to increase cellular proliferation.  相似文献   

15.
As it is previously shown (Tsyrlova et al., 1986), the level of humoral immune response is not only determined by the reaction of peripheral lymphoid system on antigenic effect, but also is bound up with the observed stem blood cell (SBC) proliferation in bone marrow (Frindel et al., 1976, Kozlov et al., 1982). Dynamics of label accumulation in bone marrow was examined when injecting antigen--sheep red blood cells labeled by radioisotope 51Cr, 125I. The peak of label accumulation in bone marrow, accompanied by the increase in proliferative SBC, was observed on the 3rd day after antigen injection. Furthermore in the course of immunization 51Cr labeled macrophage assortment was changed in time in such a way that a greater number of macrophages was accumulated in bone marrow on the 3rd and 4th days in the immunized animals in comparison with the intact ones. The macrophages in bone marrow are likely to take part in antigen uptake and to mediate its effect on SBC proliferation.  相似文献   

16.
Antioxidants are known to influence metabolism and promote cell survival in a number of cell culture systems. However, their effects on the modulation of bone cell differentiationin vitroare not clearly defined. In the present studies we have investigated the effects of β-mercaptoethanol (βME) and ascorbate alone and in combination on human osteoprogenitors derived from bone marrow fibroblasts. In primary marrow cultures, βME stimulated colony formation (2-fold), alkaline phosphatase activity (3.5-fold) and, increased DNA synthesis (8-fold) after 21 days. Cell proliferation was increased significantly by βME during the first 4 days of a 10-day culture period, indicating stimulation of marrow osteoprogenitor proliferation. Ascorbate did not significantly augment the effects of βME in primary cultures or long-term cultures of passaged bone marrow fibroblasts. These findings indicate a potential beneficial role for βME addition for the optimal maintenance of colony formation, cell proliferation and differentiation of marrow osteoprogenitor cells in primary human bone marrow fibroblast cultures.  相似文献   

17.
In Riptortus clavatus (Thunberg) (Heteroptera : Alydidae), growth and development of cuticular structures were compared between normal antennae and the antennae whose distal (4th) segment had been amputated during the 1st instar. The total length of the remaining 3 segments was 51% of the normal antenna. From the 2nd ecdysis onwards, the 2nd and 3rd segments grew excessively, and after adult emergence, the length of the operated antennae was 84% that of a normal antenna, although a typical 4th segment, separated from the 3rd segment by an intersegmental membrane, never developed. On the new distal (3rd) segment of operated antennae, long fine sensory hairs and grooved pegs, which characterize the normal distal (4th) segment, began to appear at the 2nd ecdysis, and successively increased in number between molts. Thus, when the distal segment was removed, the remaining segments tended to gradually compensate for the loss, both in terms of length and cuticular structures.  相似文献   

18.
Three cultures immobilized by entrapping within alginate gel beads and packed in near-horizontal acrylic columns (15.0° angle) were used for alcohol/malolactic fermentation of grape must. Immobilized cells of Saccharomyces cerevisiae spp. chablis were placed in the 1st column, S. cerevisiae cells (an alcohol-sucrose-tolerant yeast) in the 2nd and the Lactobacillus delbrueckii cells in the 3rd column. Grape must with different levels of sugar(s), were each fed to the bioreactor columns at dilution rate of 0.74 h−1 and recycled at 37.0C. The percent fermentation efficiency and yield using the 1st and 2nd columns for grape must containing 33.3% sugar(s) were 92.9 and 91.5%, respectively, and the wine had 15.5% alcohol after 23 cycles (∼ 50 h fermentation). The viability of the immobilized yeast cells in the alginate gel-bead was 84%± 4.0. Immobilized Lactobacillus delbrueckii cells were then added to the 3rd column (in series 37.0C) and the three cultures resulted in alcohol/malolactic fermentation of the grape must, evidenced by the high level of alcohol formed and simultaneous transformation of malic to lactic acid. Sensory evaluation of the wine scored high (7.8 ± 2.0 based on a value of 10.0) and indicated the potential of using multiple immobilized cells of two specific yeast cultures and a malolactic Lactobacillus for wine production.  相似文献   

19.
通过整体实验观察国产重组白介素3(IL-3)对射线和环磷酰胺所致小鼠造血功能低下的疗效;以体外实验分析其疗效机理。实验结果表明:(1)rhIL-3腹腔或皮下连续5天注射能全面提高7Gy照射小鼠9天时股骨骨髓CFU-E、BFU-E、CFU-Mix和CFU-GM的产率和数量,其效果强弱与注射途径和用药剂量有关。rhIL-3对小鼠股骨骨髓有核细胞总数和内源性脾结节数的改善影响小。(2)rhIL-3对环磷酰胺所致小鼠造血功能低下亦有改善效果,并与起用时间和剂量有关。(3)rhIL-3对人骨髓细胞和CFU-GM集落形成有明显的增强作用。小鼠骨髓细胞对rhIL-3缺乏反应;对rmIL-3有增殖分化加强的反应。rmIL-3体外共育能提高正常及照射2Gy小鼠骨髓细胞体外培养后CFU-GM的产率和数量。文中讨论了IL-3的应用前景及合理方案问题。  相似文献   

20.
Growth and glycogen content of Chironomus anthracinus in Lake Esrom, Denmark was examined during summer stratification in 1992 and 1993. Simultaneously, effects of oxygen deficiency on glycogen utilization and survival were experimentally studied. The population consisted of almost fullgrown 4th instar larvae in 1992 and 2nd and 3rd instar larvae in 1993. Growth rate and glycogen content changed as hypolimnetic oxygen deficiency increased. During a 1st phase of stratification dry weight and glycogen content increased (2nd and 3rd instars) or was almost constant (4th instar) but decreased significantly during the following 2nd phase. This change from growth to degrowth and utilization of endogenous glycogen reserves correlated with a change in the thickness of the microxic layer (<0.2 mg O2 1–1) above the sediment surface. The layer increased from 2–3 m in phase 1 to 4–5 m in phase 2, and we suggest that this deteriorated the oxygen conditions and resulted in a change in larval energy metabolism from fully aerobic during the 1st phase to partly anaerobic in the 2nd phase. During the 2nd phase larval metabolism was estimated at less than 20% of normoxic rate. Experimental exposure of the larvae to anoxia indicated highly different survival of young larvae (2nd and 3rd instars) and older larvae (large 4th instars). The morality of young larvae was 50% after three days in anoxia at 10 °C, whereas only 25% of the older larvae had died after 3–4 weeks under similar conditions. Extending the treatment, however, resulted in increased death rate of the 4th instar larvae with only 10% surviving after seven weeks. The anaerobic metabolism of 4th instar larvae as estimated from glycogen degradation at 10 °C was 5% of normoxia in the interval from 0–5 days but 1.5% in the interval from 20–25 days. It is concluded that survival of C. anthracinus in anoxia is very limited, but traces of oxygen in the environment allowing for faint aerobic metabolism prolong the survival time of the larvae from a few days (2nd and 3rd instars) or a few weeks (4th instar) to probably 3–4 months.  相似文献   

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