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101.
荔枝品种亲缘关系的AFLP分析 总被引:21,自引:4,他引:21
应用AFLP技术,对39个荔枝品种进行了遗传多样性分析及分类研究。筛选出适于荔枝AFLP分析的最佳引物组合3对,分别为EcoRI AAC+MseI CTG,EcoPd AGC+MseI CAT,EcoRI ACC+Msel CAT。在分子水平上,荔枝品种的遗传多样性并非形态学性状所体现的那样丰富。AFLP分析将39个荔枝品种分成了6组,与传统的以果皮龟裂片隆起类型为分类标准的分类没有一致性。初步建立起荔枝主要栽培品种的分子标记标准图谱。应用AFLP技术对来自两个不同地方的两个荔枝品种(桂味、妃子笑)进行了鉴别。 相似文献
102.
琯溪蜜柚光合特性的研究 总被引:30,自引:2,他引:30
利用Li-6400 光合作用仪对田间条件下7 年生琯溪蜜柚的光合特性进行了系统研究。结果表明: (1) 琯溪蜜柚外围叶片晴天的净光合速率(Pn) 日变化为双峰曲线, 首峰出现在8~10 时, 次峰值小于首峰值, 出现在14 时以后; 阴天呈单峰曲线; 内膛叶片Pn 日变化有双峰、单峰和锯齿形3 种类型。(2)观测期内Pn季节变化近似双峰曲线。(3) 不同月份和不同枝条叶片Pn 对光和CO2 响应有较大差别, 光补偿点和饱和点分别为16~46 和1 026~1 656μmol·m-2·s-1 , 表观量子效率0.01725~0.05431 ; CO2 补偿点和饱和点分别为51~80 和822~926μmol·mol -1 , 羧化效率0.01769~0.05191 ;Pn对CO2 的响应进程近似双曲线。(4) Pn与气孔导度、蒸腾速率、光照强度正相关, 与胞间CO2 浓度负相关, 与温度、湿度和叶面水气压亏缺的相关性比较复杂。(5) Pn 与叶片的叶绿素含量和比叶重之间没有明显相关性。(6) 光合适温为24~34 ℃。 相似文献
103.
104.
为了探索微波处理作为木质包装替代处理方法的可能性,对不同规格和含水量的杨树木块进行微波处理试验,结果表明:频率为2450MHz的微波能够穿透厚度为10cm的杨树木材;当微波功率为900W时,规格为10cm×10cm×10cm和10cm×10cm×2.5cm的新木块中黄斑星天牛(Anoplophora nobolis)幼虫完全死亡所需时间分别为5min和2min;而干木块中则仅需3min和30s.对微波处理引起木材温度变化和水分损失以及天牛幼虫的水分损失进行了初步研究. 相似文献
105.
苹果矮化砧木‘辽砧2号’选育 总被引:2,自引:0,他引:2
从1135系的助列涅特与M9杂交实生苗中选出优良苹果矮化砧木—辽砧2号(原代号80-1-6),经过22年田间观查和区试鉴定,其矮化性、早果性、丰产性、生根性与M26相近,适应性强于M26,以其为中间砧的富士树栽后6年进入盛果期,平均株产为23.5kg,同龄M26为17.2kg;8年生树冠积为4.07m3,同龄M26为4.58m3,树体存活率较M26高55%,平均每666.7m2产量1000kg以上;与基砧山定子和生产上主栽的富士系、元帅系、国光系等品种亲和性良好,以自根砧和中间砧方式利用均可。 相似文献
106.
BsC3-41杀蚊幼制剂对蚊幼虫毒杀效果研究 总被引:2,自引:0,他引:2
通过以BsC3- 41杀蚊幼制剂对 3种蚊幼虫进行生物活性测定和野外灭蚊试验 ,结果表明 :该制剂对致乏库蚊CulexfatigansWiedemann的毒杀效果最好、对中华按蚊AnophelessinensisWiedemann次之、对白纹伊蚊AedesalbopictusSkuse的效果较差 ,2 4小时LC50值分别为 0 2 0 2 5 μg/ml、 2 5 363μg/ml和 5 9 730 2 μg/ml。野外水体灭蚊使用 3ml/m2 的浓度防治淡色库蚊效果可达 98 88%~ 1 0 0 0 0 % ,使用 1 0ml/m2 的浓度防治中华按蚊效果可达96 81 %~ 1 0 0 0 0 % ,使用 2 0 0ml/m2 的浓度防治白纹伊蚊效果达到 90 64%以上。 相似文献
107.
DU Yi-mei TANG Ming LIU Chang-jin HONG Zhi-gang KE Qin-mei DI Jiu-fang LUO Hong-yan HU Mou-xian HU Xin-wu XI Jiao-ya TANG Bi Jurgen Hescheler 《园艺学报》2004,20(9):1537-1541
AIM: To determine the role of Kv1.2, Kv1.5, Kv2.1 in the hypoxia pulmonary vasoconstriction (HPV). METHODS: Male Wistar rats were divided into two groups: normoxic group and hypoxic group. The single smooth muscle cell was obtained from pulmonary artery of Wistar rats with acute enzymatic digestion method. The conventional whole-cell patch clamp technique was used to record the resting membrane potential (Em) and the potassium currents of voltage-gated potassium channel (IKv) in rat pulmonary arterial smooth muscle cells (PASMC). Intracellular application of Kv1.2/Kv1.5/Kv2.1 antibodies (1∶125) was conducted through the whole-cell patch clamp system. RESULTS: ① Em of PASMC was depolarized after 24 h hypoxia compared with that of control cells . IKv of PASMC was decreased after 24 h hypoxia, . ② The mixture of Kv1.2/Kv1.5/Kv2.1 antibodies depolarized Em and inhibited IKv in PASMC from normoxic rat, whereas the mixture of Kir2.1/Kir2.3/Kir4.1 antibodies had no effects on them. ③ The mixture of Kv1.2/Kv1.5/Kv2.1 antibodies and the mixture of Kir2.1/Kir2.3/Kir4.1 antibodies had no effects on IKv and Em from rats hypoxic for 24 h. CONCLUSION: Kv1.2, Kv1.5, Kv2.1 might be oxygen sensitive potassium channels which mediated HPV. 相似文献
108.
AIM: To observe effects of homocysteine and antagonized effects of taurine on electronic leakage and free radical production in myocardial mitochondria. METHODS: Myocardial mitochondria of rat heart was isolated, and was broken by supersonic wave to prepare submitochondria. Recombinant of succinic acid cytochrome c reductase was prepared with mitochondria of porcine heart. They were co-incubated with homocysteine and/or taurine with various concentration. The H2O2 and O2- were determined by chemiluminescence methods. The taurine transporter of heart mitochondria and its propert, and effects of homocysteine on its function were studied with glass filter. RESULTS: Homocysteine stimulated oxygen free radical production in heart mitochondria, submitochondria, and succinic acid cytochrome c in a concentration-dependent manner. Although taurine itself did not affect oxygen free radical production, taurine did inhibit oxygen free radical production in mitochondria, submitochondria and succinic acid cytochrome c in a concentration-dependent manner. Taurine transporters of Na+-dependent were existed in mitochondria membrane. Homocysteine inhibited taurine transtport in mitochondria in a concentration-dependent manner. CONCLUSIONS: Taurine inhibited electronic leakage and oxygen free radical production induced by homocysteine in electron transport chain. There were taurine transporters in mitochondria membrane, and transport functions of taurine transporter were inhibited by homocysteine. 相似文献
109.
AIM: To investigate the relationship between p21WAF1gene polymorphisms and protein expression in breast carcinoma. METHODS: Polymerase chain reaction single-strand conformation polymorphisms technique (PCR-SSCP) and immunohistochemical assay of S-P immunostaining technique were used to study polymorphisms of p21WAF1 and protein expression respectively on the specimen of paraffin-embedded tissues in 100 cases of breast carcinomas and 40 benign breast diseases as control. RESULTS: Two p21WAF1 gene polymorphisms were found in 18% (18/100) of breast carcinomas and 5% (2/40) of control samples. The difference between the two groups was statistically significant (χ2=3.94, P<0.05). The positive immunohistochemical reaction of p21WAF1 protein were found in 50% (50/100) of breast carcinomas and 12.5% (5/40) of control samples. The difference between the two groups was statistically significant (χ2=16.84, P<0.01). The positive immunohistochemical reaction of p21WAF1 protein were found in 100% (18/18) of breast carcinomas with p21WAF1 gene polymorphisms and 39% (32/82) of no p21WAF1 gene polymorphisms. The difference between two groups was statistically significant (χ2=21.95, P<0.01). The p21WAF1 gene polymorphisms were correlated with the protein expression in breast carcinomas (r=0.576, P<0.01). CONCLUSION: p21WAF1 gene polymorphisms may create the different copies of mRNA and may make relevant protein molecules. 相似文献
110.
ZHU Ying-yuan WANG Zi-neng ZENG Yi-ke ZHENG Pei-e XU Jian-ping GUO Zu-wen TANG Fu-xing 《园艺学报》2004,20(6):1038-1041
AIM: To obverse the expression and localization of urocortin on ultrathin cryosections of syncytiotrophoblast of human term placenta with immunocytochemistry technique under transmission electron microscope. METHODS: The human term placenta tissue from Cesarean delivery and normal labor were fixed in 4% paraformaldehyde, and then divided into two parts. One part was for regular immunocytochemistry under microscope, and the other part was used to prepare ultrathin cryosections for immunocytochemistry under transmission electron microscope. RESULTS: 1.Uroncortin mainly distributed in cytoplasm of syncytiotrophoblast of human term placenta under microscope. Urocortin also appeared in cytoplasm in some stromal cells. 2. Under transmission electron microscope, the anti-urocortin gold particles were observed in cytoplasm of syncytioptrophoblast ultrathin cryosections and sited on rough-surfaced endoplasmic reticulum. The anti-urocortin gold particles also appeared on nucleus and nuclear membrane of syncytiotrophoblast. CONCLUSION: Syncytiotrophoblast of human term placenta synthesized and secreted urocortin. The internalization of urocortin within syncytiotrophoblast nuclear indicates that urocortin may act as intracrine. 相似文献