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281.
A genetic linkage map of common carp (Cyprinus carpio L.) was constructed using Type I and Type II microsatellite markers and a pseudo-testcross mapping strategy. The microsatellite markers were isolated from microsatellite-enriched genomic libraries and tested for their segregation in a full-sib mapping panel containing 92 individuals. A total of 161 microsatellite loci were mapped into 54 linkage groups. The total lengths of the female, male and consensus maps were 2,000, 946, and 1,852?cM, with an average marker spacing of approximately 13, 7, and 11?cM, respectively. Muscle fiber-related traits, including muscle fiber cross-section area and muscle fiber density, were mapped to the genetic map. Three QTLs for muscle fiber cross-section area and two QTLs for muscle fiber density were identified when considering both significant and suggestive QTL effects. The QTLs with largest effects for muscle fiber cross-section area and muscle fiber density were 21.9% and 18.9%, and they were located in LG3, respectively.  相似文献   
282.
Ning  Baile  Zhang  Qinxin  Wang  Nanbu  Deng  Minzhen  Fang  Yongqi 《Neurochemical research》2019,44(5):1159-1166
Neurochemical Research - β-Asarone (1,2,4-trimethoxy-5-[(Z)-prop-1-enyl]benzene) is an essential component of Acorus tatarinowii Schott volatile oil. Previous research has observed that...  相似文献   
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284.
目的:观察红芪、黄芪及配伍当归对环磷酰胺(CTX)所致血虚模型小鼠的干预作用。方法:昆明种小鼠随机分为7组,每组10只。采用CTX复制小鼠血虚模型,正常组与模型组小鼠用生理盐水灌胃,阳性对照组小鼠给予驴胶补血颗粒,四个给药组分别灌胃红芪、黄芪、红芪-当归组(5:1)及黄芪-当归组(5:1),连续灌胃7 d后,采用血细胞分析仪测定各组小鼠外周红细胞(RBC)、淋巴细胞(LYM)、红细胞压积(HCT)、白细胞(WBC)、血小板(PLT),取脾脏、胸腺、股骨,计算脾脏指数(SI)、胸腺指数(TI)的变化,进行网织红细胞计数(RC)、骨髓有核细胞计数,并对股骨进行病理切片观察。结果:与正常组比较,模型组小鼠RBC、WBC、HCT、PLT、LYM等含量均降低(P<0.05),与模型组比较,红芪及不同配伍各组小鼠中SI、TI均显著升高(P<0.05),红芪-当归组及黄芪-当归组可显著提高外周RBC、HCT、WBC、PLT、LYM的含量(P<0.05),可升高RC及骨髓有核细胞数量(P<0.05),股骨病理切片显示有所改善。结论:红芪-当归(5:1)与黄芪-当归(5:1)配伍对血虚模型小鼠的改善作用及补血作用优于红芪、黄芪的单独作用,黄芪-当归(5:1)效果更佳。  相似文献   
285.
The study described the uncertainties of NPP estimation due to larch defoliation by caterpillars during 2001–2004 in Northeastern China, which is an order of magnitude larger in area and severe than all previous recorded outbreaks. Using “representative needles” collected in the field, we related spectral responses and photosynthetic contents of needles to ecophysiological parameters in NPP estimation for different degrees of caterpillar damage. It is concluded that locations of reflection peaks at or near green red near-infrared wavelength moving toward long-wave direction with aggravated damage degree, which is useful to earlier prediction of caterpillar damage. Contents of chlorophyll-a reduced by 40.26, 66.29 and 86.88% for light, moderate and severe damage samples respectively compared with healthy, chlorophyll-b reduced by 20.79, 52.67 and 82.39%, and carotenoid reduced by 9.80, 45.06 and 73.15%. Estimated NDVI values decreased by 9.89–31.08, 38.16–47.47 and 61.90–66.71%, respectively. It results to the decrease of LAI by 39.76–74.34, 85.85–93.64 and 94.61–98.51%, and reduction of FPAR and APAR by 10.16–37.47, 39.21–57.24 and 63.60–80.44%. In addition, the increased minimum visible reflectance during 580–680 nm leads to the decrease of estimated aboveground biomass by 14.62, 48.86 and 56.84%, and reduction of estimated autotrophic respiration by 10.32, 39.11 and 46.95%. Ultimately, the caterpillar outbreak results to the directly underestimation of NPP by 10.01–64.63, 39.32–75.37 and 80.26–100% for light, moderate and severe samples compared with healthy. Furthermore, such impacts of forest insect disturbances should be accounted for in NPP modeling to reduce the uncertainties of estimation.  相似文献   
286.
条斑紫菜抗高温和快速生长细胞株系HB的建立及栽培   总被引:1,自引:0,他引:1  
本文主要应用单细胞培养技术培育紫菜新品系,以建立紫菜细胞工程快速育苗系统。通过酶解技术分离出紫菜叶状体细胞,并进行多克隆,从中获得4个细胞纯系植株(HA,HB,HC,HD)。对该4个细胞株系进行了纯系培养,并对其细胞苗和丝状体的生长速度和抗高温(19℃,21℃,23℃,25℃)性进行了测定。结果显示,HB株系具有较高的抗高温性和最快生长速度。在1998年到2000年间,在江苏省启东县海丰海区对HB株系进行了海上栽培实验,结果显示,实验组的产量高于当地对照组产量,证明了条斑紫菜HB株系不仅具有较高的抗高温性,而且也有较快生长速度。本实验说明应用细胞工程进行条斑紫菜育种是一条很好的快速育种途径。  相似文献   
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288.
Although 4-tert-butylphenol (4-t-BP) is a serious aquatic pollutant, its biodegradation in aquatic environments has not been well documented. In this study, 4-t-BP was obviously and repeatedly removed from water from four different environments in the presence of Spirodela polyrrhiza, giant duckweed, but 4-t-BP persisted in the environmental waters in the absence of S. polyrrhiza. Also, 4-t-BP was not removed from autoclaved pond water with sterilized S. polyrrhiza. These results suggest that the 4-t-BP removal from the environmental waters was caused by biodegradation stimulated by the presence of S. polyrrhiza rather than by uptake by the plant. Moreover, Sphingobium fuliginis OMI capable of utilizing 4-t-BP as a sole carbon and energy source was isolated from the S. polyrrhiza rhizosphere. Strain OMI degraded 4-t-BP via a meta-cleavage pathway, and also degraded a broad range of alkylphenols with linear or branched alkyl side chains containing two to nine carbon atoms. Root exudates of S. polyrrhiza stimulated 4-t-BP degradation and cell growth of strain OMI. Thus, the stimulating effects of S. polyrrhiza root exudates on 4-t-BP-degrading bacteria might have contributed to 4-t-BP removal in the environmental waters with S. polyrrhiza. These results demonstrate that the S. polyrrhiza–bacteria association may be applicable to the removal of highly persistent 4-t-BP from wastewaters or polluted aquatic environments.  相似文献   
289.
目的:观察右美托咪定在气管异物取出术中对患儿呼吸、循环及术后恢复情况的影响。方法:40例行气管异物取出术患,随机分为右美托咪定组(D组)(n=20)和生理盐水组(S组)(n=20),分别在麻醉诱导前10min静脉输注右美托咪定0.8μg/kg和等容量的生理盐水,输注时间为10min。术中高频射流呼吸机给氧,保持患儿自主呼吸,泵注丙泊酚和瑞芬太尼维持麻醉。结果:D组患儿术中屏气、咳嗽、喉痉挛、术中SP02〈90%显著低于S组(P〈0.05);D组丙泊酚及瑞芬太尼用量减少(P〈0.05)。结论:在气管异物取出术中应用右美托咪定有很大的优势,对呼吸系统影响小,血流动力学平稳,术后并发症少。  相似文献   
290.
Although important factors governing the meiosis have been reported in the embryonic ovary, meiosis in postnatal testis remains poorly understood. Herein, we first report that SRY‐box 30 (Sox30) is an age‐related and essential regulator of meiosis in the postnatal testis. Sox30‐null mice exhibited uniquely impaired testis, presenting the abnormal arrest of germ‐cell differentiation and irregular Leydig cell proliferation. In aged Sox30‐null mice, the observed testicular impairments were more severe. Furthermore, the germ‐cell arrest occurred at the stage of meiotic zygotene spermatocytes, which is strongly associated with critical regulators of meiosis (such as Cyp26b1, Stra8 and Rec8) and sex differentiation (such as Rspo1, Foxl2, Sox9, Wnt4 and Ctnnb1). Mechanistically, Sox30 can activate Stra8 and Rec8, and inhibit Cyp26b1 and Ctnnb1 by direct binding to their promoters. A different Sox30 domain required for regulating the activity of these gene promoters, providing a “fail‐safe” mechanism for Sox30 to facilitate germ‐cell differentiation. Indeed, retinoic acid levels were reduced owing to increased degradation following the elevation of Cyp26b1 in Sox30‐null testes. Re‐expression of Sox30 in Sox30‐null mice successfully restored germ‐cell meiosis, differentiation and Leydig cell proliferation. Moreover, the restoration of actual fertility appeared to improve over time. Consistently, Rec8 and Stra8 were reactivated, and Cyp26b1 and Ctnnb1 were reinhibited in the restored testes. In summary, Sox30 is necessary, sufficient and age‐associated for germ‐cell meiosis and differentiation in testes by direct regulating critical regulators. This study advances our understanding of the regulation of germ‐cell meiosis and differentiation in the postnatal testis.  相似文献   
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