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91.
本文报导桑蚕在蛹期进行卵巢移植试验的成功,并调查了卵巢移入雄蛹后的生物学效应。明确了血液中卵黄原蛋白向卵巢移行的时期是在蛹期。试验表明:蛹龄2h的雌、雄蛹在低温抑制后进行移植为适宜;卵巢植入雄蛹后受体发育良好,羽化率达82.5%~100%;雄蛹内卵巢能形成成熟卵,但卵大小、重量和卵肉蛋白质、核酸含量以及卵超微结构发生了一些变化;用人工单性生殖方法处理雄蛹内的发育卵,得到14.2%~16.0%的成胚率,进一步研究可望获得后代。  相似文献   
92.
目的探讨损伤血管局部表达的基质细胞衍生因子1α是否能介导内皮祖细胞参与损伤血管的再内皮化,抑制新生内膜的增生。方法培养、获取小鼠骨髓源性内皮祖细胞,采用改良的Boyden小室测定基质细胞衍生因子1α诱导的内皮祖细胞迁移及AMD3100(CXCR4的拮抗剂)对其的影响。分别将内皮祖细胞培养基、内皮祖细胞及AMD3100孵育过的内皮祖细胞经心脏穿刺注射给颈动脉损伤小鼠,在14天后取损伤血管检测内皮祖细胞募集情况、再内皮化情况及新生内膜增生情况。结果基质细胞衍生因子1α能诱导内皮祖细胞迁移(与对照组比较P<0.01),AMD3100能有效阻断该作用(AMD3100组与对照组比较P>0.05)。较多注射的内皮祖细胞成功归巢到损伤血管处(14.2±3.6个/切片),AMD3100孵育过的内皮祖细胞仅少量可成功归巢(4.0±2.5个/切片);内皮祖细胞注射能加速损伤血管的再内皮化(内皮祖细胞移植组比对照组:83.45%±5.44%比66.46%±6.16%,P<0.01),AMD3100孵育过的内皮祖细胞注射则无效(68.02%±6.68%,与对照组比较P>0.05);内皮祖细胞移植组新生内膜增生厚度(19237±1875μm2)和内膜中膜比值(0.94±0.12)均小于对照组(34676±2412μm2和1.77±0.18)及AMD3100组(32451±2081μm2和1.60±0.17)(P<0.01)。结论基质细胞衍生因子1/CXCR-4在介导移植的内皮祖细胞修复损伤血管内膜中起重要作用。  相似文献   
93.
[目的]探讨4个德国鸢尾(Iris germanica L.)新品种组培苗移栽技术。[方法]以新筛选的4个德国鸢尾新品种"白与蓝"、"黄与白"、"白天鹅"和"惊险"的组培苗为试验材料,通过移栽试验研究了组培苗移栽成活率的影响因素。[结果]炼苗时间的长短对4个鸢尾新品种的组培苗移栽成活率没有明显影响;而不同的移栽基质对其影响较大,筛选出的最佳移栽基质为园土∶草炭(V∶V)=1∶1。[结论]该研究可为今后的鸢尾工厂化繁殖种苗提供理论依据。  相似文献   
94.
AIM: To evaluate the effect of vascular endothelial growth factor (VEGF) on the ovarian tissues during transplantation. METHODS: Twenty regularly cycling rats were randomly divided into 2 groups: the rats in group A received fresh autologous ovarian transplantation without VEGF administration (n=10); the rats in group B received fresh autologous ovarian transplantation with VEGF administration (n=10). Four weeks after transplantation, the ovarian tissues and sera of the rats were collected for histological examination and determination of the hormone levels. RESULTS: The serum concentration of estradiol in group B was significantly higher than that in group A (P<0.05). Four weeks after transplantation, we found that the ovarian tissues were significantly developed, and the average size of the ovaries in group B was significantly larger than that in group A (P<0.05). CONCLUSION: The ovarian tissues with VEGF administration develop better than those without VEGF administration. VEGF can increase the graft vascularity and the percentage of surviving tissues.  相似文献   
95.
AIM:To study the immunosuppressive and protective effects of human α1-antitrypsin (hAAT) on pancreatic β-cell transplantation. METHODS: An NIT-1 cell line (NIT-hAAT) was constructed, which can stably express the protein of hAAT. The BALB/c mice were intraperitoneally injected with NIT-1 and NIT-hAAT cell lines twice to induce cytotoxic T-lymphocytes (CTL). The apoptotic situation, the cytokine expression, and the mRNA expression of inflammatory factors were examined after mixed culture of CTL with NIT-1or NIT-hAAT cell line pretreated with mitomycin. Both cell lines were transferred into the left renal capsule of the diabetic mice to dynamically observe the changes of blood sugar and body weight, the serum levels of insulin and C-peptide, and the pathological changes of the transplanted sites. RESULTS: The results of extended CTL killing assay showed that the cytotoxic effect on NIT-hAAT cell acceptor mice was significantly reduced compared with NIT-1 cell acceptor mice. hAAT effectively reduced apoptosis, inhibited the mRNA expression of inflammatory factors IL-1β and IL-6, and adjusted the balance of Th1/Th2 cytokine expression. After NIT-hAAT was transplanted into the diabetic mice, blood glucose decreased obviously and maintained for 28 d. The serum levels of insulin and C-peptide increased obviously. The infiltration of the inflammatory cells in the transplanted sites significantly reduced. CONCLUSION:hAAT has the abilities of reducing cytotoxic effect of CTL on the β-cells, inhibiting inflammatory factor expression, and stopping short-term immunological rejection of the acceptor. hAAT has obvious immunosuppressive and protective effects on pancreatic β-cell transplantation for treatment of diabetes.  相似文献   
96.
中国樱桃‘对樱桃’(Prunuspseudocerasus)生根试管苗移栽,直接下地成活率为0%,通过温室过渡驯化后移栽下地成活率达95%以上,这个过程中驯化移栽的空气相对湿度、温度和营养土移栽的排水因素是其成败的关键。特此做了如下试验,证明在根系发达、无污染的健壮试管苗、蛭石或蛭石 珍珠岩(体积比1:1)是最理想的过渡驯化基质、有效叶片数5片以上的条件下成活率最高达95.5%。相对空气湿度在90%到100%成活率可以稳定保持在95%以上、棚内气温为22 ̄26℃,地温15 ̄18℃,对试管苗过渡驯化效果生长最好。40d后移栽到营养土(将壤土、沙子、草炭按照体积比例为4:2:1混合)容器里,将刚栽完的营养土钵苗摆在地面上,可以快速排去积水,一般在3 ̄5d内水排去50%,苗成活率高达95%。  相似文献   
97.
通过对武乡海棠(Malus honanensis Rehd.)优良矮砧S_(18)、S_(20)两个单系的0.2mm微茎尖脱毒组织培养技术研究,解决了微茎尖切割、接种、分化及生根移栽等一系列技术难题,获得了S_(20)、S_(18)一批脱毒试管苗及移栽壮苗.分化数分别达2.0和3.6,生根率达76.1%和90.0%,平均根长2cm以上,平均根数5条,移栽成活率达78%.  相似文献   
98.
山楂芽外植体培养及试管苗栽培的研究   总被引:1,自引:0,他引:1  
山楂芽外植体在改良MS+BA2 mg/1(下同)+IAA0.05+LH500或改良MS+BAImg/+NAA0.01+LH500的培养基上,冬、春乃至盛夏和秋季采取的顶芽、腋芽或混合芽,经0—5℃处理2—7天,均可成功地诱导分化丛生芽.在适宜的温、湿度等条件配合下,充足的光照是山楂试管苗移栽成活的主要因素.(?)用粪肥能提高移栽成活率,且幼苗生长茁壮.盛夏季节,因高温的影响移栽成活率低.根系发达的试管苗露天栽植也能成活.试管苗移栽入圃的适期为茎顶开放、主茎伸长的生长旺盛期.此时的成活率高.  相似文献   
99.
AIM: To establish a method of isolating,culturing the adipose tissue-derived mesenchymal stem cells in vitro and to investigate the possibility of exogenous transplanting the adipose tissue derived mesenchymal stem cells for treatment of rat acute myocardial infarction.METHODS: 18 male rats were separated randomly into 3 groups: sham surgery group (control,n=6),acute myocardial infarction control group (AMI,n=6) and myocardial infarction plus cell transplantation group (AMI+cell,n=6).The infarcted hearts were made by occlusion of left coronary artery.The mesenchymal stem cells were isolated from the rats’ peritoneum by using digestion methods and reproduced in vitro,then the cells were labeled with BrdU and implanted into the infarcted heart of the rats.Heart functions were measured 4 weeks after implantation.The hearts were also harvested for pathological and histoimmunochemical observations to determine the survival and location of the implanted cells.RESULTS: Plenty of mesenchymal stem cells were obtained from the adipose tissue of rats’ peritoneum.Compared with the AMI group,the left ventricular systolic pressure in the cell therapy group was increased significantly (P<0.01),the left ventricular end-diastolic pressure was decreased (P<0.01),and the ratio of the left ventricular pressure rise and decay (±dp/dt) was decreased (P<0.05).The number of blood vessels was increased at the boundary of infarction site by pathological observation.The labeled cells were founded in the infarcted myocardium and the blood vessel wall.CONCLUSION: The adipose tissue is a new optional stem cell source.The methods of exogenous transplantation of adipose tissue derived mesenchymal stem cells for treatment of AMI is effective and feasible.  相似文献   
100.
AIM: To investigate the depressant effect and mechanism of atorvastatin on the chronic rejection of aortic allograft in rats.METHODS: The models of abdominal aorta transplantation were made with micro-surgery in rats.The recipients were divided into three groups: allograft control group,atorvastatin-treated group and isograft control group.Vascular intimal thickness in all of the groups was observed by histological examination.The expression of proliferation cell nuclear antigenl(PCNA) and α-smooth muscle actin(α-SMA) were determined by immunohistochemistry.The content of nitric oxide was measured by nitrate reductase chromatometry.RESULTS: The vascular intimal thickness in atorvastatin-treated group (11.60%±2.40%) was lower than that in allograft control group (34.60%±6.40%,P<0.05) and higher than that in isograft control group (1.15%±0.65%,P<0.05).The expression level of PCNA was decreased in atorvastatin-treated group (4.80%±0.80%) than that in allograft control group (18.40%±1.80%,P<0.05) and higher than that in isograft group (1.20%±0.40%,P<0.05).CONCLUSION: The expression of PCNA in the transplanted aorta is suppressed by atorvastatin,which results in relief of chronic rejection of aortic allograft.  相似文献   
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