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191.
以‘金艳’猕猴桃为材料,研究其果实生长动态规律及不同采收期(谢花后153 d、168 d、183 d和198 d)(Ⅰ、Ⅱ、Ⅲ、Ⅳ)的软果品质。结果表明:金艳猕猴桃在凉山州西昌市一般4月中旬进入盛花期;在生育期内,果实尺寸(纵、横径)呈前期逐渐增大,后期趋于平稳的变化,谢花后59 d内为果实快速膨大期,谢花后101 d进入生长缓滞期;随采收期延迟,果实软熟时可溶性固形物、干物质和糖酸比呈逐渐升高的趋势;早期采收(Ⅰ、Ⅱ)果实软熟时可溶性固形物、干物质、糖酸比和总氨基酸偏低,淀粉和粗纤维较高;晚期采收(Ⅲ、Ⅳ期)果实软熟时可溶性固形物、干物质、糖酸比较高,淀粉和粗纤维较低,风味更浓,口感更佳;Ⅳ期维生素C和总氨基酸含量最高,但采收较晚不利于当年鲜果销售;若作为鲜果,其最佳采收期为Ⅲ期,Ⅱ期和Ⅳ期可作为备选采收期;作为保健品加工原料,最佳采收期为Ⅳ期。  相似文献   
192.
为探讨有色茧色素物质在蚕体内的代谢机制,检测了有色茧主要色素物质的含量及其在家蚕5龄幼虫不同时期中肠、血液、丝腺组织中的消长变化,分析色素物质从中肠进入血液再转运到丝腺的时序差异。有色茧中,黄茧的色素以类胡萝卜素化合物为主,绿茧的色素以黄酮类化合物为主。黄酮类化合物、类胡萝卜素化合物在家蚕5龄幼虫中肠、血液、中部丝腺、后部丝腺中的含量均呈现龄初低、龄末高的趋势,其中,黄酮类化合物在熟蚕组织中的含量是中肠>血液>中部丝腺>后部丝腺;类胡萝卜素化合物在熟蚕组织中的含量是中部丝腺>后部丝腺>中肠>血液。2种色素物质含量变幅最大的是后部丝腺组织,结黄茧蚕和结绿茧蚕的黄酮类化合物分别增加406.55%、202.50%,类胡萝卜素化合物分别增加211.80%、250.84%。黄酮类化合物在5龄幼虫丝腺组织的绝对含量是结绿茧蚕大于结黄茧蚕,类胡萝卜素化合物在5龄幼虫丝腺组织的绝对含量是结黄茧蚕显著大于结绿茧蚕,与在不同颜色蚕茧中检测到的2种色素物质含量一致。研究结果提示:黄酮类化合物在5龄幼虫中肠组织中积累较多,类胡萝卜素化合物在丝腺组织中积累较多;丝腺组织中2种色素物质的含量与茧色密切相关;来自桑叶中的2种色素物质经中肠消化吸收后,再通过血液进入丝腺组织并产生累积效应。  相似文献   
193.
长江源头草地类型及利用意见   总被引:1,自引:0,他引:1  
长江发源于被称为生命“禁区”的唐古拉山地区,海拔高,气候恶劣。本文是作者在1986年实地考察唐古拉山地区草地资源的基础上,较全面的介绍了长江源头地区的草地类型、面积、分布规律等资料,并根据该地实际提出了进一步开发利用的意见。  相似文献   
194.
Through dairy herd improvement (DHI) data analysis to predict somatic cell count (SCC) of Ningxia area in time, which providing a reference for the prevention and treatment of mastitis in dairy cows, making the DHI data more effective and timely in guiding the dairy industry production. Using the difference method to make the average cow somatic cell data form September 2011 to February 2016 stabled, then used the seasonal ARIMA model to analysis, fitting and forecasting data. The auto.arima function of R software had been used to calculate the optimal time series that finally confirmed the model was ARIMA (1,1,0)(1,1,0)[12], AIC was -3.67. The Acf test showed that the residual had no significant autocorrelation; Ljung-Box test showed that all P-value>0.5, indicating that the residual was white noise, and this model could be used to make predication for the next 24 months. The forecast function of the R software was used to predict the dairy cows SCC from March 2016 to February 2017, and the forecast map was drawn. The predicted results showed that the SCC of the entire Ningxia area were showing a downward trend. The SCC would be the least in January 2017,and the predictive value was about 253 100 per mL. It would be the largest in March 2016, was about 439 600 per mL. The results also showed that the dairy cows SCC in Ningxia was higher than the critical value of 20 million of subclinical mastitis. It suggested that the prevention and treatment of dairy cow mastitis need to be strengthened in Ningxia area. At the same time, if the data of the dairy cows SCC was added in timely, the data model should be updated to make it more close to the true value, which would be more meaningful to the actual instruction.  相似文献   
195.
196.
The aim of this study is to evaluate the efficacy of frozen Azawak colostrum supplementation on body weight (BW), average daily gain (ADG), reproductive parameters (mean age at first parturition, fertility, fecundity, prolificacy) and mortality rate among red kids. The study was conducted at the goat farm secondary centre of Maradi in Niger from September 2010 to September 2011. The control animals (n = 20) were left with their mother, while the treatment animals (n = 20) received in addition 50 ml/animal/day of bovine colostrum at birth and 15 ml/animal/day from d2 to d15. Weight was measured weekly from birth to d365. Mortalities were also recorded over the same period. For reproductive parameters, observations began at weaning (d197). Growth rate was higher (p < 0.001) in supplemented animal, and the treatment effects on ADG were observed up to 150 day after the end of supplementation. A similar long‐lasting trend was also observed in relation to the mortality rate (25% for ColG vs. 55% for ConG; p = 0.05). The age at first kidding tended to be lower in the treated group (13.8 ± 0.7 vs. 14.1 ± 0.8 month; p < 0.1). In conclusion, mild bovine colostrum supplementation induces a long‐lasting positive impact on growth rate and to a lower extent on reproduction parameters and survival rate.  相似文献   
197.
Several methods have been proposed to advance the onset of the breeding season in horses. Most of them are based on the exposure to an artificial lighting period combined with hormonal treatments. Mares exposed to an artificial photoperiod are most often housed indoors where the ambient temperature is often higher than the outside temperature. Mares held in barns are also exposed to different daylight intensities than horses kept outside, depending on the architecture. In the current study, we evaluated the impact of ambient temperature, daylight intensity and changes in body condition score (BCS) on the timing of first ovulation after winter anestrus in mares exposed to an artificial photoperiod. Mares (n = 211) were housed in barns with different ambient temperature and daylight exposure but with the same artificial photoperiod exposure (except for a natural photoperiod control group). Artificial photoperiod as well as an increase in BCS over the winter significantly advanced the first spring ovulation. The BCS at the start and end of the anestrus period did not have an effect on the interval to first ovulation and neither did the modest increase in ambient temperature in the barn. However, a higher light intensity during the daytime significantly advanced the first spring ovulation. The results of this study suggest that exposure to more sunlight advances the onset of the breeding season. This effect is likely mediated through the biological effect of short wavelength blue light and its impact on melatonin suppression and biological rhythms. We suggest that greater/direct exposure to the blue light component of daylight improves the response to the artificial photoperiod. The results of the present study can further assist to optimize the conditions that lead to an efficient spring transition of breeding mares.  相似文献   
198.
通过DNA测序不仅可以更好地认识生命的本质,了解生物的差异性、进化及发展史,而且为重组DNA的研究提供了方向,在疾病诊断及基因分型方面具有非常重要的实用价值。首先从发现DNA是遗传物质开始,简要回顾了第一、二和三代测序技术的整个发展历程,以及各自的优缺点和主要测序技术或平台;其次,重点介绍了由PacBio公司开发的第三代测序典型技术--单分子实时测序技术(SMRT)和ONT纳米孔测序技术的原理、方法和技术流程,并总结了第三代测序技术的应用领域,包括基因组重测序、do novo测序、转录组研究、甲基化检测、与疾病相关的结构变异检测,以及流行病学中病毒准种分析等应用;再次,比较了三代测序技术在转录组测序和表观遗传学研究中的技术优势,第三代测序技术在基因组重复区域或结构变异等研究领域具有非常明显的优势,对多种疾病的研究意义重大,已成为未来重要的精准诊断工具,此外,凭借对重要经济物种遗传信息的解析,育种工作者通过建立基因与性状的关联,对持有优良性状基因的个体进行人工选育,大大缩短了育种年限;最后,对第三代测序技术在医疗、农业、环境等领域的应用前景进行了展望。  相似文献   
199.
旨在通过对FGF21、受体FGFR1和FGFR2在小鼠毛囊第1生长周期中的定位和表达情况的研究,以探索FGF21、受体FGFR1和FGFR2在毛囊发育过程中的作用。选取1、3、5、8、12、17、21和23日龄小鼠背部皮肤,采用免疫组织化学技术,实时荧光定量PCR和蛋白免疫印迹技术检测FGF21、FGFR1和FGFR2 mRNA及蛋白表达。结果显示:在小鼠毛囊第1生长周期中,FGF21主要表达于毛囊毛乳头、毛基质、内外根鞘以及毛囊周围的结缔组织中;FGFR1在毛囊各部均有表达,且在退化期(12~17日龄)和静止期(18~21日龄)主要表达于内外根鞘中;FGFR2广泛表达于毛囊各部。1、3、5、8、12、17日龄FGF 21 mRNA表达量极显著低于23日龄(P<0.01),21日龄的表达量低于23日龄,差异不显著(P>0.05);1~5日龄和23日龄FGF21蛋白表达量较高。1、3、5、8、12、21、23日龄FGFR1 mRNA表达量极显著低于17日龄(P<0.01);FGFR1蛋白表达量从12日龄开始上升,在17日龄时达到最高,之后又呈下降趋势。1、5、8、12、21和23日龄FGFR2 mRNA表达量极显著低于17日龄(P<0.01),在3日龄的表达量低于17日龄,差异不显著(P>0.05);FGFR2蛋白在1~17日龄都有较高表达。综上表明,在第1个毛囊生长周期中,FGF21对参与毛囊形成的成纤维细胞的增殖和分化具有重要作用,诱导毛囊由生长期进入退化期。FGFR1对内外根鞘细胞的增殖、分化有着明显作用,诱导毛囊由退化期进入静止期。FGFR2对毛囊内细胞增殖、分化具有重要作用,诱导毛囊由生长期和退化期进入静止期。  相似文献   
200.
• Developed a two-step synthetic route to anti-plant-virus candidate NK0238. • NK0238 exhibited a broad antivirus spectrum in greenhouse. • NK0238 showed comparable antivirus activities as controls in field trials. • NK0238 was safe to birds, fish, bees and silkworms. • NK0238 has a very good prospect in commercial development. It has previously been shown that tryptophan, the biosynthesis precursor of Peganum harmala alkaloids, and its derivatives have anti-TMV activity both in vitro and in vivo. Further exploration of this led to the identification of NK0238 as a highly effective agent for the prevention and control of diseases caused by plant viruses, but the existing routes are unsuitable for its large-scale synthesis. This study optimized a route for two-step synthesis of this virucide candidate via reaction of l-tryptophan with triphosgene to produce l-tryptophan-N-carboxylic anhydride, which then reacts with n-octylamine to give NK0238 at up to 94% yield and nearly 97% HPLC purity. In addition, the route was used for the preparation of NK0238 on a>40 g scale permitting further assessment of its antivirus activity in the greenhouse and field experiments, and toxicity tests. NK0238 exhibited useful antiviral activities against a variety of viruses both in greenhouse and field experiments. The toxicity tests showed that NK0238 was not acutely toxic to birds, fish, honey bees and silkworms. The optimized route provides a solid foundation for its large-scale synthesis and subsequent efficacy and toxicity studies, its excellent activity and safety make NK0238 a promising drug candidate for further development.  相似文献   
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