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1.
<正>当窗外猫头鹰的"咕咕"声和外公的呼噜声配成一首滑稽的奏鸣曲,我知道,夜已经很深了。穿好衣服,提上鞋子,我蹑手蹑脚地溜出家门。今晚,对,趁着夜深人静,我要独自走入森林,找到外公提到过的那棵老橡树。哪怕田鼠啃咬我的脚趾,虫虫钻进我的衣领,我都会在树下屏住呼吸,耐心守候,因为……  相似文献   

2.
赵福瑜 《化石》2007,(3):19-21
地球上十二属种动物与人类的关系存在决定意识,人们的社会存在决定人们的社会(思想)意识。人类产生“十二兽”观念并制订,实行十二兽历法,正是人类自身起源于“十二兽”的先祖这一客观事实在人们头脑中的反映。十二兽:我国又称十二禽,十二属,十二物,十二生肖等。所谓十二兽,我国汉族是指鼠,牛,虎,兔,龙,蛇,马,羊,猴,鸡,狗,猪。让我们从十二兽历法的产生和起源来探讨地球上十二属种动物(十二兽)的先祖与人类进化的关系。世界上四大文明古国———中国、印度、埃及和巴比伦各有其“十二兽历法”,内容上大同小异。中国汉族:鼠,牛,虎,兔,龙,蛇,…  相似文献   

3.
烟草趣话     
笔者不会抽烟,不喜欢烟,记得小时候看大人吸烟,那是一小烟袋,铜制的,有个咀子放烟丝,另一头用嘴吸,烟袋里装有水,当用火柴点燃烟丝时,嘴就随时缓缓吸烟,几下子就吞云吐雾了。由于好奇,大人走后,我就仿效试试,由于吸气太大,一下子把烟袋中的水都吸到口里了,满嘴烟味极不好受,以后再不玩这东西了。后来时兴纸烟,当闻到烟气时头就不舒服,从此与烟绝了缘至今。  相似文献   

4.
《生命世界》2012,(10):94-95
野生红豆杉,冰川世纪遗留下来的古老树种,以它顽强的生命力屹立在地球上已几百万年。在人类出现在这个星球以前,它就以红彤彤的红豆果,扮靓了地球的山间和密林。它树姿优美,枝繁叶茂,苍劲挺拔,一派生机盎然,令人敬畏。它果实鲜红,艳丽无比,圆如珍珠,寄托相思之情,令人爱怜。它全身是宝,强身健体,防癌抗癌,历史悠久,令人感动。  相似文献   

5.
本文记了分别采自云南高黎贡山的栅蛛科栅蛛属Hahnia 2新种:垭口栅蛛,新种S.yakouensis sp.nov.和肾形栅蛛,新种S.reniformis sp.nov..垭口栅蛛后眼列前曲,交媾腔大,扁圆形,交媾孔1个,位于交媾腔下缘,交媾管粗,呈"人"字形下行分成2支再向两侧扭曲.纳精囊有一肓管斜向上伸出,鉴于上述特征而与Hahnia mridulae Tikader,1970不同.肾形栅蛛交媾孔2个,位于生殖厣腹面中央,纳精囊1对,大,肾形,插入器始于生殖球左下方,鉴于上述特征而与Hahnia xinjiangensis Wang et Liang,1989不同. Abstract: The present paper deals with two new species of the genus Hahnia collected from the Gaoligong Mountains Region of Yunnan Province, China: Hahnia yakouensis sp. nov., Hahnia reniformis sp. nov..  相似文献   

6.
李秉滔   《广西植物》1983,(3):167-170
<正> 灌木,通常高3米,枝条细,粗3—5毫米,树皮近灰色,具细条纹,小枝具翅,无毛。叶薄纸质,椭圆形至卵状长圆形,无毛;中脉细,两面凸起,侧脉纤细,5—7对,两面稍凸起,未达叶缘而网结,叶柄长不及2毫米,无毛;托叶挟三角形,长3—4毫米,基部扩大,近耳形,顶端急尖。花腋生,单朵或稀2朵簇生,萼片和花盘互生,无花辦。雄花:花梗丝状,长3—3.5厘米,基部被微柔毛;萼片4枚,覆瓦状排列,披针形,长4.5毫米,  相似文献   

7.
青海蚕豆种质资源形态多样性分析   总被引:10,自引:3,他引:10  
对153份青海蚕豆种质资源的形态多样性进行鉴定, 结果表明, 青海蚕豆种质资源具有丰富的形态多样性,平均多样性指数为0.8033,其中青海地方蚕豆品种多样性最丰富,平均多样性指数为0.8288.通过多变量的主成分分析,前6个主成分代表了蚕豆形态多样性的87.89%.基于形态性状,把153份蚕豆种质聚类并划分为3大组群.第Ⅰ组群,初花天数较长,植株中等,子粒中等,单株荚数和粒数多,单株产量较高;第Ⅱ组群,初花天数较短,株高较矮,子粒小,单株荚数和粒数较多,单株产量低;第Ⅲ组群,初花天数较短,株体较高,单株荚数和粒数少,但子粒较大,单株产量较高.  相似文献   

8.
韦裕宗   《广西植物》1984,(3):195-198
<正> 短叶琼楠 新种 图10 Beilschmiedia brevifolia Y. T. Wei, sp. nov. 乔木,高约8米,小枝略粗壮,无毛;树皮平滑或微裂;顶芽卵圆形,无毛,直径约5毫米,先端尖。叶薄革质,对生,常聚生于枝顶,椭圆形至狭椭圆状披针形,2.5—4(6)厘米,宽1.5—2.5(3)厘米,先端钝,基部近圆形,稀近楔形,两面无毛,干时腹面深灰色,背面黑褐色,中脉在叶面微下陷,在下面凸起;侧脉每边约7条,与网脉在两面凸起;叶柄短,长2—5毫米,无毛。花未见。果序顶生或腋生。果近球形,直经约1.5厘米,干后黑色,果  相似文献   

9.
在非洲的坦桑尼亚北部,有一片茂密的森林,名叫丹堵鲁。为了追踪一种名叫岩象鼩的小动物,生物学家格蕾丝已经在这片森林里待了几个星期。此刻的她,双膝跪地、鼻尖儿蹭着泥,正聚精会神地调试着微型摄影机。哈,调试完毕,我简直是天才!格蕾丝咧开嘴巴,得意地咯咯笑着,这下我一定能……哎呦,什么什么东西钻进了我的鼻子,痒、痒,啊——阿嚏!  相似文献   

10.
马志朝  何烈琪  林伟南  刘玮 《蛇志》2008,20(1):17-19
目的 通过对容县2000~2007年84例狂犬病流行病学特点进行分析,探讨流行回升的因素,分析目前防治过程中存在的问题,提出狂犬病的预防对策和措施.方法 收集2000~2007年容县狂犬病疫情报告资料及对狂犬病病例的个案调查资料进行分析.结果 近年来,容县狂犬病疫情明显上升,成为有史以来流行高峰,最高年发病率3.04/10万.发病以农民,学生为主,男性多于女性,全年均有病例发生,无明显季节性,狂犬病暴露动物以犬伤为主,暴露部位以头颈部为最危险,潜伏期最短.结论 为有效预防狂犬病流行,应进一步建立完善犬类的管理的法律、法规,使预防狂犬病进入法制轨道,以有效控制狂犬病流行.伤后未能及时正确处理,暴露后免疫率低,是狂犬病发生的重要原因.加强宣传,提高狂犬病的防控知识,政府部门齐抓共管,采取综合性防控措施,才能有效控制狂犬病的流行.  相似文献   

11.
新收集大豆种质资源主要品质鉴定与评价   总被引:5,自引:0,他引:5  
对"十五"期间新收集、保存入国家种质资源库的841份大豆种质资源的蛋白质、脂肪两个主要品质性状进行了鉴定评价.结果表明,蛋白质、脂肪含量均近似正态分布,最大频度分别出现在41.01%~ 42.00%含量范围和20.01%~21.00%含量范围.与以前收集、保存的种质资源相比,新收集种质资源的蛋白质含量呈下降趋势,而脂肪含量和蛋脂总量呈上升趋势.不同类型种质资源的品质性状比较结果表明,地方品种的蛋白质总体水平明显高于育种材料、引进种质和选育品种3种类型,引进种质的脂肪、蛋脂总量的总体水平明显高于其他3种类型.国内种质资源高蛋白质大豆占有率高于引进种质资源;引进种质资源高脂肪、高蛋白兼高油的大豆占有率高于国内种质资源.  相似文献   

12.
作为重要的粮油饲兼用作物,大豆为世界膳食提供高达约71%的蛋白质和29%的油脂。随着人口不断增长和大豆消费需求的不断提高,在有限的耕地面积和单产条件下,大豆品质的遗传改良则更具重要意义。该文综述了大豆种子蛋白和油脂含量两个重要品质性状调控的研究进展,总结了调控大豆蛋白和油脂合成的关键酶和转录因子及因子间的相互作用,并根据蛋白和油脂合成代谢调控途径中关键酶和转录因子作用机制,绘制了大豆蛋白和油脂合成代谢的分子调控网络。此外,该文还讨论了当前大豆种子蛋白油脂含量调控研究存在的瓶颈及对策,以期为大豆种子品质的遗传改良和高产品种培育提供参考。  相似文献   

13.
Subvisible particles in formulations intended for parenteral administration are of concern in the biopharmaceutical industry. However, monitoring and control of subvisible particulates can be complicated by formulation components, such as the silicone oil used for the lubrication of prefilled syringes, and it is difficult to differentiate microdroplets of silicone oil from particles formed by aggregated protein. In this study, we demonstrate the ability of flow cytometry to resolve mixtures comprising subvisible bovine serum albumin (BSA) aggregate particles and silicone oil emulsion droplets with adsorbed BSA. Flow cytometry was also used to investigate the effects of silicone oil emulsions on the stability of BSA, lysozyme, abatacept, and trastuzumab formulations containing surfactant, sodium chloride, or sucrose. To aid in particle characterization, the fluorescence detection capabilities of flow cytometry were exploited by staining silicone oil with BODIPY 493/503 and model proteins with Alexa Fluor 647. Flow cytometric analyses revealed that silicone oil emulsions induced the loss of soluble protein via protein adsorption onto the silicone oil droplet surface. The addition of surfactant prevented protein from adsorbing onto the surface of silicone oil droplets. There was minimal formation of homogeneous protein aggregates due to exposure to silicone oil droplets, although oil droplets with surface-adsorbed trastuzumab exhibited flocculation. The results of this study demonstrate the utility of flow cytometry as an analytical tool for monitoring the effects of subvisible silicone oil droplets on the stability of protein formulations.  相似文献   

14.
15.
对大豆的蛋白质含量和脂肪含量进行QTL定位,可为其分子标记辅助育种提供依据。以回交导入系群体中黄13×中黄20的BC2F5的100个家系为材料,分析群体的SSR标记多态性,采用近红外光谱分析技术测定群体蛋白质含量和脂肪含量。构建了一张涵盖大豆20个连锁群、总长为948.01 c M、平均遗传距离为8.78 c M、包含108个SSR标记的大豆遗传连锁图谱。共检测到与蛋白质含量相关的QTL 5个,与脂肪含量相关的QTL 9个,其中Satt445~Sat_303连续2年被检测到与脂肪含量相关,Satt445~Sat_303与Satt543~Satt574均被检测到与蛋白质含量和脂肪含量相关,Sat_389~Satt590、Satt238~Satt388及Satt685~Sat_381均与脂肪含量相关。  相似文献   

16.
利用野生大豆资源创新优质抗病大豆新种质   总被引:14,自引:1,他引:13  
利用野生大豆与栽培大豆种间杂交中间材料与高产栽培大豆回交转育,创新选育出蛋白质含量45%以上,蛋脂总含量63%以上,分别抗大豆疫霉根腐病,抗大豆灰斑病,农艺性状优良的大豆创新种质资源3份。其中,龙品8802-1抗大豆疫霉根腐病兼抗大豆灰斑病,蛋白质含量45.64%,脂肪含量18.42%,蛋脂总含量64.06%;龙品01-757抗大豆灰斑病,蛋白质含量45.99%,脂肪含量19.4%,蛋脂总含量65.39%;龙品9501,中抗大豆灰斑病,蛋白质含量45.11%,脂肪含量18.32%,蛋脂总含量63.43%。研究结果表明,利用含有野生大豆血缘的种间杂交材料与高产栽培大豆回交,是拓宽大豆遗传基础,创新选育优质、抗病、农艺性状优良大豆新种质资源的有效途径。  相似文献   

17.
Sesame is an important oil crop for the high oil content and quality. The seed oil and protein contents are two important traits in sesame. To identify the molecular markers associated with the seed oil and protein contents in sesame, we systematically performed the association mapping among 369 worldwide germplasm accessions under 5 environments using 112 polymorphic SSR markers. The general linear model (GLM) was applied with the criteria of logP≥3.0 and high stability under all 5 environments. Among the 369 sesame accessions, the oil content ranged from 27.89%–58.73% and the protein content ranged from 16.72%–27.79%. A significant negative correlation of the oil content with the protein content was found in the population. A total of 19 markers for oil content were detected with a R2 value range from 4% to 29%; 24 markers for protein content were detected with a R2 value range from 3% to 29%, of which 19 markers were associated with both traits. Moreover, partial markers were confirmed using mixed linear model (MLM) method, which suggested that the oil and protein contents are controlled mostly by major genes. Allele effect analysis showed that the allele associated with high oil content was always associated with low protein content, and vice versa. Of the 19 markers associated with oil content, 17 presented near the locations of the plant lipid pathway genes and 2 were located just next to a fatty acid elongation gene and a gene encoding Stearoyl-ACP Desaturase, respectively. The findings provided a valuable foundation for oil synthesis gene identification and molecular marker assistant selection (MAS) breeding in sesame.  相似文献   

18.
A detailed RFLP-genomic map was used to study the genetics of oil, seed and meal protein and sum of oil and seed/meal protein contents in a recombinant doubled-haploid population developed by crossing black- and yellow-seeded Brassica juncea lines. Two yellow seed color genes (SC-B4, SC-A6) and one QTL for erucic acid content (E1b) showed pleiotropic effect for oil, protein and sum of oil and seed/meal protein contents. Six (O-A1, O-A6, O-A9, O-B3, O-B4, O-B5) and five (SP-A1, SP-A9, SP-B4, SP-B6, SP-C) QTLs were significant for oil and seed protein contents, respectively. Tight linkage of three of these QTLs (SP-A1, SP-A9, SP-B4, O-A1, O-A9, O-B4), with opposite effects, poses challenge to the plant breeders for simultaneous improvement of negatively correlated (r = −0.7**) oil and seed protein contents. However, one QTL for oil content (O-B3) and two for seed protein content (SP-B6, SP-C) were found to be unlinked, which offer the possibility for simultaneous improvement of these two traits. QTLs significant for meal protein (MP-A1, MP-A6, MP-A9, MP-B5, MP-B6) were significant at least for oil, seed protein or sum of oil and seed/meal protein contents (T-A6, T-A7, T-B4, T-B5). Sum of oil and seed protein contents and sum of oil and meal protein contents had a perfect correlation, as well as same epistatic interactions and QTLs with similar additive effect. This indicates that protein in seed or meal has practically the same meaning for breeding purposes. Epistatic interactions were significant for the quality traits, and their linkage reflected association among the traits.  相似文献   

19.
Soybean is globally cultivated primarily for its protein and oil. The protein and oil contents of the seeds are quantitatively inherited traits determined by the interaction of numerous genes. In order to gain a better understanding of the molecular foundation of soybean protein and oil content for the marker-assisted selection (MAS) of high quality traits, a population of 185 soybean germplasms was evaluated to identify the quantitative trait loci (QTLs) associated with the seed protein and oil contents. Using specific length amplified fragment sequencing (SLAF-seq) technology, a total of 12,072 single nucleotide polymorphisms (SNPs) with a minor allele frequency (MAF)?≥?0.05 were detected across the 20 chromosomes (Chr), with a marker density of 78.7 kbp. A total of 31 SNPs located on 12 of the 20 soybean chromosomes were correlated with seed protein and oil content. Of the 31 SNPs that were associated with the two target traits, 31 beneficial alleles were identified. Two SNP markers, namely rs15774585 and rs15783346 on Chr 07, were determined to be related to seed oil content both in 2015 and 2016. Three SNP markers, rs53140888 on Chr 01, rs19485676 on Chr 13, and rs24787338 on Chr 20 were correlated with seed protein content both in 2015 and 2016. These beneficial alleles may potentially contribute towards the MAS of favorable soybean protein and oil characteristics.  相似文献   

20.
Oil bodies obtained from oilseeds have been exploited for a variety of applications in biotechnology in the recent past. These applications are based on their non-coalescing nature, ease of extraction and presence of unique membrane proteins—oleosins. In suspension, oil bodies exist as separate entities and, hence, they can serve as emulsifying agent for a wide variety of products, ranging from vaccines, food, cosmetics and personal care products. Oil bodies have found significant uses in the production and purification of recombinant proteins with specific applications. The desired protein can be targeted to oil bodies in oilseeds by affinity tag or by fusing it directly to the N or C terminal of oleosins. Upon targeting, the hydrophobic domain of oleosin embeds into the TAG matrix of oil body, whereas the protein fused with N and/or C termini is exposed on the oil body surface, where it acquires correct confirmation spontaneously. Oil bodies with the attached foreign protein can be separated easily from other cellular components. They can be used directly or the protein can be cleaved from the fusion. The desired protein can be a pharmaceutically important polypeptide (e.g. hirudin, insulin and epidermal growth factor), a neutraceutical polypeptide (somatotropin), a commercially important enzyme (e.g. xylanase), a protein important for improvement of crops (e.g. chitinase) or a multimeric protein. These applications can further be widened as oil bodies can also be made artificially and oleosin gene can be expressed in bacterial systems. Thus, a protein fused to oleosin can be expressed in Escherichia coli and after cell lysis it can be incorporated into artificial oil bodies, thereby facilitating the extraction and purification of the desired protein. Artificial oil bodies can also be used for encapsulation of probiotics. The manipulation of oleosin gene for the expression of polyoleosins has further expanded the arena of the applications of oil bodies in biotechnology.  相似文献   

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