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111.
Oriental persimmon (Diospyros kaki) originated in Eastern Asia, and many indigenous cultivars have been developed in China, Japan, and Korea. These cultivars are classified into four groups based on their natural astringency loss on the tree and seed formation: pollination-constant non-astringent (PCNA), pollination-variant non-astringent (PVNA), pollination-constant astringent (PCA), and pollination-variant astringent (PVA). PCNA is the most desirable type because the fruit can be eaten without any postharvest treatment; therefore, one of the goals of our persimmon breeding programs is to release superior PCNA cultivars. The PCNA genotype is recessive to the other three non-PCNA genotypes, and PCNA-type F1 offspring are obtained exclusively from crosses among PCNA genotypes. Moreover, the number of superior PCNA cross-parents have been limited. In the late 1980s, inbreeding depression became obvious, especially in terms of fruit size, tree vigor, and productivity. To mitigate the inbreeding, a backcross program using PCNA [(non-PCNA × PCNA) × PCNA] was started in 1990. This process, however, was inefficient because only 15% of the offspring were PCNA, and all offspring had to be grown to the fruiting stage. Therefore, molecular markers linked to the PCNA locus were developed for discriminating PCNA offspring. A molecular marker linked to Chinese PCNA has also been developed.  相似文献   
112.
AIM: To observe the therapeutic effect of Jiedu-Qingfei mixture on Mycoplasma pneumoniae (MP)-infected rat lung tissues and to explore its mechanism. METHODS: SD rats (n=40) were randomly divided into 4 groups:blank control group, model group, Jiedu-Qingfei group and positive control group, with 10 rats in each group. The rats in experimental groups were slowly dripped with 1×109 CFU/L MP solution into their nostrils for 4 d. One rat in each group was sacrificed for MP nucleic acid detection at the second day after inoculation, and the other rats were given gavage therapy. The rats in blank control group and model group were intragastrically given the same volume of normal saline, the rats in Jiedu-Qingfei group were given 8 mL/kg Jiedu-Qingfei mixture daily for 4 weeks, and the rats in psoitive control group were given dexmethasone sodium phosphate (0.5 mg·kg-1·d-1). After the experiment, the rats were killed. The serum and bronchoalveolar lavage fluid (BALF) were collected for detecting the levels of interleukin-12 (IL-12), IL-13 and TNF-α by ELISA. The right lung tissues were used for pathological observation and HE staining, while the left lung tissues were used to detect the expression of NF-κB p50, I-κBα and p38 mitogen-activated protein kinase (p38 MAPK) at mRNA and protein levels. RESULTS: The results of MP nucleic acid detection showed that all the rats except blank control group were MP nucleic acid positive, indicating that the rat model of MP infection was successfully established. On the 1st day of the treatment, the pathological scores of the lung tissues in model group and Jiedu-Qingfei group were significantly higher than those in blank control group (P<0.05). After treatment, the pathological scores of the lung tissues in mo-del group were significantly higher than those in blank control group and Jiedu-Qingfei group. The levels of IL-12 in the serum and BALF in model group were significantly lower than those in blank control group after MP infection (P<0.05), while those after treatment with Jiedu-Qingfei mixture were significantly higher than those in model group (P<0.05). The levels of IL-13 and TNF-α in the serum and BALF of MP-infected rats were increased significantly, while those after treatment with Jiedu-Qingfei mixture were significantly lower than those in model group (P<0.05). The mRNA expression levels of NF-κB p50 and p38 MAPK in model group were increased significantly (P<0.01). After treatment, the mRNA expression levels of NF-κB p50 and p38 MAPK were decreased significantly compared with model group (P<0.01). The mRNA expression level of I-κBα in model group was significantly lower than that in control group. After treatment, the mRNA expression of I-κBα in Jiedu-Qingfei group was significantly higher than that in model group (P<0.05). The protein levels of NF-κB p50 and p38 MAPK in the lung tissues of model group were significantly higher than those of blank control group. After treatment, the protein expression of NF-κB p50 and p38 MAPK was decreased significantly. The protein level of I-κBα in model group was significantly lower than that in blank control group, and after treatment with Jiedu-Qingfei mixture, the protein expression level of I-κBα was increased significantly (P<0.05). CONCLUSION: Jiedu-Qingfei mixture may attenuate lung tissue inflammation caused by MP through NF-κB and p38 MAPK pathways.  相似文献   
113.
Diabetes is characterized by an absolute or relative deficiency in β-cell mass, which cannot be reversed with existing therapeutic strategies. The restoration of the endogenous islet β-cells can stabilize the level of blood glucose. The islet β-cells can be obtained from the directional differentiation of stem cells, but the process is complex and has the risk of teratomas generation. Cell direct reprogramming, one terminal differentiated cell can transdifferentiate into another kind of terminal differentiated cell, which is other than directional differentiation from stem cells. Direct reprogramming gives rise to the generation of islet β-cells from one terminal differentiated cell, may be preferable for diabetes therapy because of its unique advantage.  相似文献   
114.
为了解喀斯特山区2个不同鲫鱼群体在蛋白质水平的遗传多样性及其遗传差异,运用聚丙烯酰胺凝胶电泳方法对喀斯特山区2个群体鲫鱼的血清转铁蛋白电泳表型及多样性进行研究。结果表明:群体克隆多样性指数表现为草海鲫鱼(0.32)﹥红鲫(0.25,对照)﹥普安鲫鱼(0.13);3个鲫鱼群体的13个克隆由9个不同的等位基因产生,等位基因的频率分别为Tf~a0.144 9、Tf~b0.202 9、Tf~c0.036 2、Tf~d0.058 0、Tf~e0.007 2、Tf~f0.239 1、Tf~g0.014 5、Tf~h0.275 4、Tf~i0.029 0;普安鲫鱼与草海鲫鱼和红鲫无共享的基因型;普安鲫鱼与草海鲫鱼之间的遗传相似性指数较高(0.714 3),遗传距离较小(0.285 7)。总体来看,草海鲫鱼的克隆多样性水平较高,其转铁蛋白多样性程度较普安鲫鱼丰富;2个群体之间存在较近的亲缘关系,未达到遗传距离种的分化标准。  相似文献   
115.
红宝玉是以10R15 为母本、10R8 为父本选育而成的中熟厚皮甜瓜一代杂种。植株长势稳健,抗病抗逆性强。全生育期95~110 d(天),果实发育期30~35 d(天)。果实短椭圆形,成熟后果面乳白色,单果质量约1.5 kg,果肉橘红色,肉厚3.5~4.0 cm,腔小不发酵,中心可溶性固形物含量17.5%,肉质紧脆,不脱蒂,耐贮耐运。平均每667 m2产量3 600 kg 左右。适宜在山东、河北、陕西、安徽等地春季保护地设施栽培。  相似文献   
116.
湘紫薯174 是以浙紫薯1 号为母本、浙紫薯3 号为父本杂交选育而成的食用型紫心甘薯新品种,薯块纺锤形,薯皮 紫红色,薯肉紫色,结薯较集中整齐,单株结薯4~5 个,大中薯率82.7% 以上,熟食味好,抗黑斑病,中抗根腐病、茎线 虫病和薯瘟病;每667 m2 鲜薯产量1 913~2 359 kg,薯干产量549~736 kg;花青素含量为714.5 mg · kg-1(FW)。适宜在湖 南、湖北、江西、江苏、浙江等地春夏薯区种植。  相似文献   
117.
Eleven grape cultivars were analysed to explore the variety differences of fresh grape phenolic profiles. The results showed that free phenolics were predominant in grape skins and pulps, and showed the higher antioxidant activities than bound. In 11 cultivars, Muscat Kyoho extracts had the highest total phenolic content in skins(10.525 mg GAE g~(–1) FW) and pulps(1.134 mg GAE g~(–1) FW), and exhibited the highest DPPH radical scavening capacity(EC_(50)=11.7 μg mL~(–1)) and oxygen radical absorbance capacity(ORAC) value(190.57 μmol TE g~(–1) FW) of free phenolic in skin. In addition, the most abundant phenolics in grape skins were found to be flavonoids such as kaempferol in Kyoho skin(541.2 μg g~(–1) FW), rutin, catechin and epicatechin in Muscat Kyoho skin(262.3, 86.3 and 70.0 μg g~(–1) FW, respectively). Furthermore, the principal component analysis showed a strong difference of phenolic profiles with the cultivars, existing forms and distributions. Pearson correlation coefficient analysis showed a significant linear correlation between total phenolic content and antioxidant activity(P0.05). Therefore, both skins and pulps were rich sources of bioactive phenolic compounds, and Muscat Kyoho was the ideal source among all samples.  相似文献   
118.
内蒙古桦木沟林场不同地貌野生花卉资源分布   总被引:1,自引:1,他引:0  
内蒙古桦木沟林场地形地貌类型广泛,野花资源丰富,尚未得到有效开发。为了解野生花卉资源习性和生物学特征,开发利用野花资源,在路径调查的基础上,采用典型样地调查法,调查分析了其野花资源分布。共调查野花资源177种,隶属于40科129属,菊科、豆科、毛茛科等种类和种群数量较丰富。不同地貌Margalef丰富度指数1.35~8.28,Shannon-Wiener指数变异范围1.42~2.59,Simpson指数为0.59~0.96,湿地草甸、疏林草地物种多样性丰富,沙地多样性最低。湿度、光照等是影响野花多样性分布的重要因素。林场分布着丰富而有较大开发价值的喜光、耐荫、耐涝、喜湿、耐旱等不同生态型野生花卉。部分野生花卉资源濒危,亟需保护。  相似文献   
119.
120.
AIM: To observe the treatment effect and its immune regulation of human amnion epithelial cells (hAECs) on Alzheimer's disease (AD)-like pathology rat model. METHODS: The hAECs were isolated from amnion with trypsin digestion, and the phenotype of hAECs was analyzed by flow cytometry. SD rats (n=48) were randomly divided into sham control group, model group, medium group and hAECs group. AD-like pathology rat model was induced by bilateral intraventricular injection of lipopolysaccharide (LPS). hAECs (5×105) were injected into the hippocampus of the AD-like pathology rats. At 2 weeks after transplantation, the animals were tested by Morris water maze to observe the function of learning and memory. The pathological change of the brain was observed by HE staining. The expression of amyloid β-protein 42(Aβ42) and Tau protein and the level of acetylcholine (ACh) in the injury brain were determined by immunohistochemistry. The survival and differentiation of hAECs in the hippocampus were measured by immunofluorescent technique. The percentages of lymphocyte subsets in the peripheral blood mononuclear cells were analyzed by flow cytometry. The contents of serum cytokines were detected by cytometric bead array. RESULTS: Compared with model group and medium group, hAECs group showed shortened escape latency (P<0.01), increased frequency of going through the platform (P<0.05), reduced loss of hippocampal neurons, decreased expression of Tau protein and Aβ42 in the hippocampus (P<0.05), increased ACh level in the hippocampus (P<0.05), decreased percentages of Th1 and Th17 subsets, increased percentages of Th2 and Treg cells (P<0.05), decreased concentrations of IFN-γ and IL-2 in the serum, and increased concentration of IL-4(P<0.05). CONCLUSION: hAECs improve the cognitive learning and memory function and alleviate pathologic damage of hippocampus through immune regulation in AD-like pathology rats.  相似文献   
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