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1.
本研究应用女母回归法、公畜内女母回归法、半同胞相关法和单元内半同胞相关法对内蒙古阿尔巴斯白绒山羊的产绒量、绒厚、毛长、体重、绒伸直长度和细度等六个性状的遗传参数进行了估测。结果表明:(1)绒量遗传力介于0.26~0.45之间;绒厚遗传力介于0.33~0.56之间;毛长遗传力介于0.23~0.32之间;体重的遗传力介于0.1 6~0.36之间;绒伸直长度遗传力为0.24;绒细度的遗传力为0.14。(2)产绒量与绒厚、绒厚与毛长、长度与绒厚、长度与毛长的遗传相关分别介于0.33~0.79、0.51~0.69 、0.38~0.60、0.74~0.90之间,存在较强的正向遗传相关;绒量与毛长、绒量与体重、绒厚与体重、细度与绒厚、细度与绒量、细度与体重的遗传相关分别为0.11~0.38、0 .06~0.17、0.15~0.36、0.02~0.11、0.24~0.35、0.13~0.32之间,存在较弱的正向遗传相关;毛长与体重、长度与绒量、长度与体重、长度与细度、细度与毛长之间的遗传相关介于-0.14~-0.28、-0.09~-0.20、-0.18~-0.23、-0.27~-0.31、-0 .17~-0.28之间,存在中等偏弱的负向遗传相关。(3)绒量、绒厚、毛长、体重的重复率分别为0.42、0.27、0.59、0.18。  相似文献   

2.
Selected trace metals were analyzed in human malignant and nonmalignant (benign) breast tissue samples by the flame atomic absorption spectrophotometric method. In malignant tissues, dominant mean concentrations were revealed by Na, K, Ca, Mg, Fe, Zn, and Al at 927, 552, 231, 61.7, 36.5, 18.3, and 8.94 microg/g, respectively, while the mean metal levels in benign tissues were 903, 435, 183, 63.3, 24.7, 14.5, and 10.1 microg/g, respectively. Average concentrations of Cd, Co, Cr, Cu, Fe, Mn, K, Ca, and Zn were noted to be significantly higher in the malignant tissues compared with the benign tissues. Significantly strong correlations (r > 0.50) in malignant tissues were observed between Mn and Co, Mn and Cd, Cd and Cr, Fe and Mn, Cd and Co, Fe and Co, Mg and Pb, Cd and Fe, Mg and Ni, Pb and Ni, Ni and Sr, and Fe and Pb, whereas, Cd and Co, Cd and Mn, Co and Mg, Co and Mn, Cu and Mn, Co and Ni, Mg and Ni, Cd and Cu, Cd and Ni, Ca and Mg, Mn and Pb, Cu and Ni, Fe and Ni, Cd and Mg, Co and Cu, Cr and Na, and Cd and Cr revealed strong and significant relationships in benign tissues at p < 0.001. Principal component analysis of the metals data yielded six principal components for malignant tissues and five principal components for benign tissues, with considerably different loadings, duly supported by cluster analysis. The study revealed a considerably different pattern of distribution and mutual correlations of trace metals in the breast tissues of benign and cancerous patients.  相似文献   

3.
头面部特征是人类学各人种进行分类的重要依据,在人类学的研究中被用作亲缘关系的证据.2006-2016年在四川、云南、西藏、贵州、海南、新疆、内蒙古共调查14个族群成人2989人(男性1434人,女性1555人)的16项头面部指标,比较这些族群头面部特征差异.研究结果如下:1)在男性族群中木雅人、尔苏人、临高人、白马人的...  相似文献   

4.
广西石灰岩山地常绿落叶阔叶混交林分类的研究   总被引:3,自引:0,他引:3  
石灰岩山地在广西占有相当大的面积,在亚热带范围形成一种独特的石灰岩常绿落叶阔叶混交林,常常与砂页岩山地的常绿阔叶林镶嵌分布。本文主要论述它的系统分类和地理分布规律。  相似文献   

5.
【目的】对白背飞虱Sogatella furcifera唾液腺蛋白进行鉴定及功能注释分类,探究不同发育阶段和不同性别的白背飞虱唾液腺蛋白之间的区别与联系。【方法】麻醉白背飞虱若虫、雄成虫和雌成虫,解剖收集唾液腺组织,提取蛋白,还原烷基化和酶解,利用液相色谱串联质谱技术鉴定蛋白。与Unigene蛋白数据库进行比对,并通过KOG分析,对唾液腺蛋白进行功能注释分类。【结果】白背飞虱若虫、雄成虫和雌成虫特有的唾液腺蛋白分别为385, 168和82个,若虫与雄成虫、若虫与雌成虫及雄成虫与雌成虫共有的唾液腺蛋白分别为319, 60和60个。KOG功能注释显示与细胞过程和信号传导相关的蛋白数量最多,若虫、雄成虫和雌成虫特有以及若虫与雄成虫、若虫与雌成虫及雄成虫与雌成虫共有的这类蛋白数量分别为81, 22, 70, 19, 21和12个,这些蛋白主要发挥着翻译后修饰、蛋白质更新、伴侣蛋白,细胞内运输、分泌和囊泡运输及信号转导作用。【结论】白背飞虱唾液腺蛋白在参与信号转导机制方面表现较为活跃,这可能与其刺吸危害有一定的关系。  相似文献   

6.
沙尘暴的危害及农业防治措施   总被引:3,自引:0,他引:3  
沙尘暴是一种灾害性天气现象,它的发生与地表植被状况有密切关系,冬春季节农田裸露和退化草地植被覆盖度低是沙尘暴的主要沙尘来源,采用农业措施整治裸露农田和退化草地是沙尘源治理的关键。本文从沙尘暴的时空分布特征、沙尘暴成因、沙尘暴的危害和沙尘暴的农业防治措施等方面进行了论述,强调了以农业措施作为沙尘源治理技术核心的观点。农业措施主要包括:(1)调整农业种植结构,改变北方目前单一的种植方式,推广粮草混作技术、粮草间作套种、草田轮作,将牧草和越冬作物(冬小麦、冬牧70黑麦等)引入农田耕作系统,增加农田冬春季节的地表覆盖;(2)推广保护性耕作制度,通过免耕、提高留茬量和留茬高度,增加冬春季根茬固土能力和地表秸秆覆盖;(3)加强草原保护和建设,通过严禁新的草原开垦,严格限制超载放牧,禁止滥采滥挖,推广分区轮牧和舍饲圈养,加大围栏封育的力度等措施恢复和重建草原植被;(4)发展集约化农牧业,推广集约化种植和养殖技术,把人们的生产活动集中在条件较好的土地上,减少沙化农田和草地压力。  相似文献   

7.
Meristematic cells of Vicia faba L. were labeled with rabbit anti-actin antibody and FITC-conjugated goat anti-rabbit lgG antibody and observed with fluorescence microscopy. Both the nuclei and chromosomes sent forth distinctive fluorescence, indicating that actin is present in the nuclei and chromosomes. Sections were reacted with the anti-actin antibody and protein A-colloidal gold and observed with transmission electron microscopy. Gold particles were found over the whole nuclei, and a lot of particles were concentrated in condensed chromatin areas and nucleoli, confirming the observations with the fluorescence microscopy. V. faba nuclei and chromosomes were treated with DNase Ⅰ and 2 mol/L NaC1, and DNA and histone-depleted nuclei and chromosomes were obtained. Indirect immunofluorescence tests showed that the DNA and histone-depleted nuclei and chromosomes reacted positively with the anti-actin antibody. These results demonstrated that actin exists not only in intact nuclei and chromosomes but also in DNA and histone-depleted nuclei and chromosomes of V. faba. In addition, the authors' results indicate that tropomyosin is present in the nuclei and chromosomes of V. faba. Presence of actin in nuclei and chromosomes as well as in DNA and histone-depleted nuclei and chromosomes of higher plants is discussed.  相似文献   

8.
建立现代植被与表土花粉的精确关系,是基于孢粉记录定量重建古植被与古气候的基础与关键.截止目前,植物群落样方记录较少参与到现代植被与花粉的统计分析中,限制了其精确关系的定量表达.本文通过中国东北样带的森林、草甸草原、典型草原和荒漠草原33个表土样品分析及植被样方调查,基于Bray-Curtis相异系数,研究了东北样带现代...  相似文献   

9.
Neuropeptide B (NPB) and W (NPW) regulate food intake and energy homeostasis in humans via two G-protein-coupled receptor subtypes, termed as GPR7 and GPR8. Rodents express GPR7 only. In animals, NPW decreases insulin and leptin levels, whereas the deletion of either NPB or GPR7 leads to obesity and hyperphagia. Metabolic and endocrine in vitro activities of NPW/NPB in adipocytes are unknown. We therefore characterize the effects of NPB and NPW on the secretion and expression of leptin and resistin, and on lipolysis, using rat adipocytes. Isolated rat adipocytes express GPR7 mRNA. NPB and NPW are expressed in macrophages and preadipocytes but are absent in mature adipocytes. Both, NPB and NPW reduce the secretion and expression of leptin from isolated rat adipocytes. NPB stimulates the secretion and expression of resistin, whereas both, NPB and NPW increase lipolysis. Our study demonstrates for the first time that NPB and NPW regulate the expression and secretion of leptin and resistin, and increase lipolysis in isolated rat adipocytes. These effects are presumably mediated via GPR7. The increase of resistin secretion, stimulation of lipolysis and the decrease of leptin secretion may represent mechanisms, through which NPB and NPW can affect glucose and lipid homeostasis, and food intake in rodents.  相似文献   

10.
《Reproductive biology》2020,20(2):254-258
We examined the effects of metabolic hormones leptin and ghrelin, and the oil-related environmental contaminants toluene and xylene on the release of ovarian hormones by gravid and non-gravid cats, as well as the functional interrelationships between metabolic hormones and contaminants. Ovarian fragments of non-gravid cats were cultured with and without leptin and toluene. Next, ovarian fragments of either non-gravid or gravid animals were cultured with and without ghrelin and xylene. Oxytocin (OT) and prostaglandin F (PGF) release was measured using ELISA.We confirm ovarian OT and PGF production by feline ovary, demonstrate the involvement of leptin and ghrelin in controlling OT and PGF release, show the direct influence of toluene and xylene on feline ovarian secretory activity, indicate the ability of leptin and ghrelin to mimic and promote the main contaminant effects, demonstrate that oil-related contaminants can prevent and even invert the effects of leptin and ghrelin on the ovary, and suggest the gravidity-associated changes in ability of ghrelin to promote xylene action on PGF (but not to OT), but not in basic ovarian OT and PGF release and their response to ghrelin or xylene.  相似文献   

11.
于贵瑞  杨萌 《应用生态学报》2022,33(5):1153-1165
自然界的生态系统为人类繁衍发展提供各式各样的生活、生产和生计的环境条件与自然资源。基于自然规律的生态系统管理是人类社会不断认知自然生态价值、保护利用自然环境和资源、创造积累生态资产、维持社会经济系统永续发展的基本途径。以此为核心认知的区域生态经济学或经济生态学,正在成为探讨人类世地球系统演变及社会经济可持续发展问题的科学研究前沿。本文以大尺度区域宏观生态系统科学为学术视角,以生态系统的多功能性与多元价值观为基础,综合论述了自然生态价值、生态资产、生态产品等基本概念;从生态学、社会学和经济学融合角度,分析讨论了生态资产形成与变化、生态产品生产与消费、生态投资与生态资产损益等过程原理;提出了区域生态资产的系统经营与生态价值实现途径,期望为我国及区域生态系统价值及生态资产的评估,生态产业及生态价值实现体系的发展提供理论和方法学参考。  相似文献   

12.
Song B  Niu S  Zhang Z  Yang H  Li L  Wan S 《PloS one》2012,7(3):e33217
Soil is one of the most important carbon (C) and nitrogen (N) pools and plays a crucial role in ecosystem C and N cycling. Climate change profoundly affects soil C and N storage via changing C and N inputs and outputs. However, the influences of climate warming and changing precipitation regime on labile and recalcitrant fractions of soil organic C and N remain unclear. Here, we investigated soil labile and recalcitrant C and N under 6 years' treatments of experimental warming and increased precipitation in a temperate steppe in Northern China. We measured soil light fraction C (LFC) and N (LFN), microbial biomass C (MBC) and N (MBN), dissolved organic C (DOC) and heavy fraction C (HFC) and N (HFN). The results showed that increased precipitation significantly stimulated soil LFC and LFN by 16.1% and 18.5%, respectively, and increased LFC:HFC ratio and LFN:HFN ratio, suggesting that increased precipitation transferred more soil organic carbon into the quick-decayed carbon pool. Experimental warming reduced soil labile C (LFC, MBC, and DOC). In contrast, soil heavy fraction C and N, and total C and N were not significantly impacted by increased precipitation or warming. Soil labile C significantly correlated with gross ecosystem productivity, ecosystem respiration and soil respiration, but not with soil moisture and temperature, suggesting that biotic processes rather than abiotic factors determine variations in soil labile C. Our results indicate that certain soil carbon fraction is sensitive to climate change in the temperate steppe, which may in turn impact ecosystem carbon fluxes in response and feedback to climate change.  相似文献   

13.
通过田间调查,研究了棉铃虫卵和龟纹瓢虫、中华草蛉空间分布的关系。研究表明,棉铃虫卵和龟纹瓢虫、中华草蛉在棉株垂直各层上的数量间相关系数6月分别为0.5696、0.8620,7月为0.8300、0.9282,8月为0.9083、0.8201,除6月龟纹瓢虫外,其余皆达显着或极显着水平;垂直格局上棉铃虫卵和龟纹瓢虫扩散系数和久野指数间相关系数分别为0.8211、0.7791,皆达极显着水平;水平格局上棉铃虫卵和中华草蛉扩散系数和久野指数间相关系数分别为0.7925、0.5228,分别达极显着和显着水平。  相似文献   

14.
夏枯草药材和种植土壤中农药及重金属残留分析   总被引:1,自引:0,他引:1  
采用气相色谱及ICP-AES法测定了安徽庐江和江苏洪泽2个种植基地的土壤和夏枯草(Prunella vulgaris L.)果穗及全草中有机氯农药及重金属含量,并根据污染指数和相关标准对土壤及药材的安全性进行了评价.测定结果表明:来源于2个基地的土壤及药材中有机氯农药及重金属含量有明显差异.庐江产果穗和全草中Pb、Cd、Cu、Cr、As及BHC含量分别为3.361和3.953、0.172和0.190、8.258和7.722、3.423和2.658、0.284和0.355、0.003和0.004 mg·kg-1,Hg和DDT未检出;洪泽产果穗和全草中Pb、Cd、Cu、Cr、Hg及BHC含量分别为2.399和1.558、0.155和0.111、7.682和6.756、4.259和3.801、0.077和0.102、0.003和0.006 mg·kg-1,As未检出,果穗中也未检出DDT.庐江基地土壤中Cd、Cu、Cr、As、Hg、BHC和DDT含量分别为0.001、12.943、47.417、1.008、0.003、0.003和0.002 mg·kg-1,Pb未检出;洪泽基地土壤中Pb、Cd、Cu、Cr、As、Hg和BHC含量分别为3.443、0.002、18.655、63.385、3.701、0.141和0.004 mg·kg-1,DDT未检出.比较结果表明:夏枯草果穗中重金属残留量均高于全草,但均低于国家限量标准;土壤中有机氯农药及重金属单项污染指数均小于1,且庐江和洪泽基地土壤的综合污染指数分别为0.286和0.399,因此,土壤污染等级属安全级且污染水平为清洁级.  相似文献   

15.
The natural world demonstrates signs of spatial–temporal order, an order that appears to us through a series of recognizable, recurring and consecutive patterns, i.e. regularities in forms, functions, behaviors, events and processes. These patterns lend insight into the modes and tempos of evolution and thus into the units, levels, and mechanisms that underlie the evolutionary hierarchy. Contributors to this special issue analyze converging patterns in the biological and sociocultural realm across and beyond classic divisions between micro- and macro-evolution; horizontal/reticulate and vertical evolution; phylogeny, ontogeny and ecology; synchronic and diachronic sociocultural and linguistic research; and tree and network diagrams. Explanations are sought in complexity theory, major transitions of evolution, and process and mechanism approaches to change; and consequences for notions such as “life”, “species”, “biological individuality”, “units” and “levels” of evolution are given.  相似文献   

16.
The postthaw motility and fertility of buffalo and cattle semen is reduced when they are cryopreserved for artificial insemination. In the present study, an attempt was made to characterize the cryogenic changes in proteases and antiprotease activities (APA) of buffalo and cattle semen because these proteolysis regulators have been reported to be associated with sperm motility and fertility. Buffalo sperm demonstrated at least two major proteases of 45 and 42 kDa and three minor proteases of 95, 52, and 33 kDa. Similarly, cattle sperm demonstrated three major proteases of 62, 45, and 42 kDa and two minor proteases of 85 and 78 kDa. Buffalo seminal plasma demonstrated at least three major proteases of 78, 68, and 62 kDa and one minor protease of 98 kDa and cattle seminal plasma demonstrated one major protease of 68 kDa and two minor proteases of 78 and 75 kDa. Except for the 45 kDa protease, most of the previously mentioned proteases were found to be metalloproteinases. Compared with fresh sperm, cryopreserved buffalo and cattle sperm demonstrated a major protease band of 52/49 kDa and the activity of this protease reduced progressively with the duration of cryopreservation. On the contrary, compared with the fresh seminal plasma, cryopreserved buffalo and cattle semen extenders displayed the presence of a new protease band of 45 kDa and demonstrated that this protease activity was leaked from buffalo and cattle cryopreserved spermatozoa. Buffalo and cattle seminal plasmas displayed at least two major APA of 86 and 26 kDa. Compared with buffalo, cattle seminal plasma demonstrated significantly greater APA. Thus, the present study demonstrated the presence of an array of proteases and APA in buffalo and cattle semen and the activities of which changed during cryopreservation. The leakage of the specific protease activity and changes in the proteases and APA might be attributed to reduced motility and fertility of cryopreserved semen in these species.  相似文献   

17.
Melatonin has the ability to improve plant growth and strengthened plant tolerance to environmental stresses; however, the effects of melatonin on mitochondrial respiration in plants and the underlying biochemical and molecular mechanisms are still unclear. The objective of the study is to determine possible effects of melatonin on mitochondrial respiration and energy efficiency in maize leaves grown under optimum temperature and cold stress and to reveal the relationship between melatonin-induced possible alterations in mitochondrial respiration and cold tolerance. Melatonin and cold stress, alone and in combination, caused significant increases in activities and gene expressions of pyruvate dehydrogenase, citrate synthase, and malate dehydrogenase, indicating an acceleration in the rate of tricarboxylic acid cycle. Total mitochondrial respiration rate, cytochrome pathway rate, and alternative respiration rate were increased by the application of melatonin and/or cold stress. Similarly, gene expression and protein levels of cytochrome oxidase and alternative oxidase were also enhanced by melatonin and/or cold stress. The highest values for all these parameters were obtained from the seedlings treated with the combined application of melatonin and cold stress. The activity and gene expression of ATP synthase and ATP concentration were augmented by melatonin under control and cold stress. On the other hand, cold stress reduced markedly plant growth parameters, including root length, plant height, leaf surface area, and chlorophyll content and increased the content of reactive oxygen species (ROS), including superoxide anion and hydrogen peroxide and oxidative damage, including malondialdehyde content and electrolyte leakage level; however, melatonin significantly promoted the plant growth parameters and reduced ROS content and oxidative damage under control and cold stress. These data revealed that melatonin-induced growth promotion and cold tolerance in maize is associated with its modulating effect on mitochondrial respiration.  相似文献   

18.
Subunit interactions among the chloroplast ATP synthase subunits were studied using the yeast two-hybrid system. Various pairwise combinations of genes encoding a, p, y, 8 and e subunits of Spinach ATP synthase fused to the binding domain or activation domain of GAL4 DNA were introduced into yeast and then expression of a reporter gene encoding p-galactosidase was detected. Of all the combinations, that of y and e subunit genes showed the highest level of reporter gene expression, while those of a and p, a and e, p and e and p and 8 induced stable and significant reporter gene expression. The combination of 8 and e as well as that of 8 and y induced weak and unstable reporter gene expression. However, combinations of a and y, p and y and a and 8 did not induce reporter gene expression. These results suggested that specific and strong interactions between y and e, a and p, a and e, p and e and p and 8 subunits, and weak and transient interactions between 8 and e and 8 and y subunits occurred in the yeast  相似文献   

19.
Wei XL  Lei P  Shi WY 《应用生态学报》2010,21(8):2086-2091
采用恒温土壤培养方法,研究了4种不同鱼蛋白有机液肥施用量[0(对照)、0.5、1.5、2.5 ml·kg-1]条件下小粉土酶活性和微生物生物量碳、氮的变化,及其与土壤养分的相关关系.结果表明:在整个培养过程中,不同鱼蛋白有机液肥施用量处理下土壤pH值变化范围为7.07~7.31,与对照无显著差异;土壤磷酸酶活性显著增强,分别为对照的1.27、1.90、1.96倍;土壤脲酶活性分别比对照提高39.81%、78.06%、173.24%;蛋白酶活性比对照提高56.37%、108.29%、199.98%;土壤微生物生物量碳、氮均随肥料添加量的增加而逐渐增大,分别为对照的1.67、3.95、4.74倍和1.21、2.43、4.06倍.土壤脲酶和蛋白酶活性以及土壤微生物生物量碳、氮在不同施用量处理下达到峰值点的时间不同.土壤磷酸酶、脲酶和蛋白酶活性、土壤微生物生物量碳、氮与土壤养分均呈显著正相关.施用鱼蛋白有机液肥可以显著促进小粉土微生物的生长及酶活性的提高,从而促进土壤有机质的分解转化和速效养分的释放.  相似文献   

20.
Variance and covariance components for piglet survival in different periods were estimated from individual records of 133 004 Danish Landrace piglets and 89 928 Danish Yorkshire piglets, using a liability threshold model including both direct and maternal additive genetic effects. At the individual piglet level, the estimates of direct heritability in Landrace were 0.035, 0.057 and 0.027, and in Yorkshire the estimates were 0.012, 0.030 and 0.025 for liability of survival at farrowing (SVB), from birth to day 5 (SV5) and from day 6 to weaning (SVW), respectively. The estimates of maternal heritability for SVB, SV5 and SVW were, respectively, 0.057, 0.040 and 0.030 in Landrace, and 0.050, 0.038 and 0.019 in Yorkshire. Both direct and maternal genetic correlations between the three survival traits were low and not significantly different from zero, except for a moderate direct genetic correlation between SVB and SV5 and between SV5 and SVW in Landrace. Direct and maternal genetic correlations between piglet birth weight (BW) and SV5 were moderately high, but the correlations between BW and SVB and between BW and SVW were low and most of them were not significantly different from zero. These results suggest that effective genetic improvement in piglet survival before weaning by selection should be based on both direct and maternal additive genetic effects and treat survival in different periods as different traits.  相似文献   

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