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1.
目的:为制定中国中年男性红细胞压积正常参考值的统一标准提供科学依据.方法:收集了中国380个地区用温氏法(Wintrobe)测定的32475例健康中年男性红细胞压积正常参考值,运用偏相关分析和因子分析对其与海拔高度(x1),年日照时数(x2),年平均相对湿度(x3),年平均气温(x4),年降水量(x5)的关系进行了研究.结果: 5个地理影响因素值与中年男性红细胞压积正常参考值的偏相关系数分别为: r1,2345=0.651,r2,1345= -0.039,r3,1245=-0.040,r4,1235=-0.281,r5,1234=0.125.运用因子分析将5个地理影响因素综合成两个公共因子F1,F2,并用其得分值代替原始数据推导出一个回归方程: y=48 464 0.1738F1-0.4125F2±4 5%结论:海拔高度是影响中年男性红细胞压积正常参考值的最主要因素.随着海拔高度逐渐增大,中年男性红细胞压积正常参考值也逐渐增大,相关性很显著.如果知道中国某地的地理因素值,可以用公因子的回归方程来估算中国某地的中年男性红细胞压积正常参考值.依据中年男性红细胞压积正常参考值与地理因素的依赖关系把中国分为青藏区,西南区,西北区,东南区,华北区,东北区六个区.  相似文献   

2.
以160头荷斯坦和娟姗奶牛作为研究对象,分别测定了其在不同温度条件下,直肠温度、呼吸频率、产奶量及乳成分,并进行了统计分析。同时设计引物扩增HSP70基因3’-侧翼区,通过PCR—SSCP技术分析hSPTO基因3’-侧翼区的多态性,并发现一个多态位点。结果表明:扩增片段为292bp,扩增产物有基因多态性,共发现4种基因型,分别为荷斯坦牛的AA(H)型、AB(H)型和娟姗牛的AA(J)刭、AB(J)型。其中B基因可能为抗热应激耩囚,这4种基囚型奶牛个体的生产性能差异不显著(P〉0.05)。  相似文献   

3.
目的:研究1-磷酸鞘氨醇(S1P)对豚鼠心室肌细胞延迟整流钾电流(IK)、内向整流钾电流(IK1)的作用。方法:实验用胶原酶酶解法急性分离豚鼠心室肌细胞,利用全细胞膜片钳的方法记录心室肌细胞的延迟整流钾电流(IK)、内向整流钾电流(IK1)。结果:①应用S1P(1.1μmol/L)后IK从(1.24±0.26)nA降至(0.95±0.23)以(P〈0.01,n=6),而S1P(2.2μmol/L)组IK从(1.43±0.31)nA下降到(1.02±0.28)nA,统计学有显著性差异(P〈0.01,H=6).而S1P(1.1μmol/L)+苏拉明(Summin)(200μmol/L)组与对照相比,IK峰值从(1.29±0.26)nA下降(1.26±0.37)nA,统计学无显著性差异(P〉0.05,n=6).②应用S1P(1.1μmol/L,2.2μmol/L)后与对照组比较,S1P(1.1μmol/L,2.2μmol/L)分别使内向整流钾电流(IK1)峰值从(-8.94±2.01)nA和(-8.81±1.55)nA下降到(18.86±1.59)nA和(-8.55±1.39)nA,统计学无显著性差异(P〉0.05,n=6).结论:S1P可降低豚鼠心室肌细胞延迟整流钾电流(IK)的幅值,同时S1P对豚鼠心室肌细胞内向整流钾通道(IK1)没有作用。  相似文献   

4.
设施葡萄萌芽调控中需冷量和需热量及其相互关系   总被引:2,自引:0,他引:2  
采用3种需冷量估算模型(≤7.2℃模型、0~7.2℃模型和犹他模型)和2种需热量估算模型(生长度小时模型和有效积温模型)分别测定了14个设施葡萄品种的需冷量和需热量,并分析了两者的相互关系。结果表明,不同葡萄品种的需冷量和需热量存在一定差异,需冷量值介于754~1489h(≤7_2℃模型)、497-757h(0~7.2℃模型)或192~755.5CU(犹他模型),需热量值为18491~24070GDH℃(生长度小时模型)或120~377D℃(有效积温模型),且欧亚种品种需热量普遍高于欧美杂种品种。另外,本研究还表明,用生长度小时模型估算出来的需热量值与需冷量值之间呈负相关关系,而有效积温模型估算出来的需热量值与需冷量值之间则呈正相关关系。  相似文献   

5.
CSN1S2、CSN3和β-Ig基因对西农萨能奶山羊产奶性能的影响   总被引:2,自引:0,他引:2  
利用PCR-RFLP技术对69只西农萨能奶山羊群体的CSN1S2基因、CSN3基因和β-Ig基因多态性与产奶性状的相关性进行了研究。结果表明,CSMS2基因的不同基因型与产奶性能间存在相关性:FF基因型个体前4胎平均产奶量显著低于NN基因型个体(P〈0.05),FF基因型个体第2胎产奶量比NN基因型个体低90kg以上(P〈0.01),提示CSMS2基因座F等位基因可能与低产奶量有关。在CSN3-HindⅢ基因座中,DE和EE基因型个体在第1、2、3、4胎产奶量和平均产奶量上差异不显著(P〉0.05);在CSN3-TaqI基因座中,TT、TC和CC3种基因型个体在第1、2、3、4胎产奶量和平均产奶量上差异不显著(P〉0.05);CSN3基因经HaeⅢ酶切没有发现多态性。对β-Ig基因5’侧翼区的分析发现,AA基因型个体各胎次产奶量均比AB型高,其中在第2、3胎产奶量和平均产奶量3项指标上都达到显著水平(P〈0.05),提示β-Ig基因的A等位基因可能与高产奶性能有关。  相似文献   

6.
李邦发 《遗传》1986,8(2):13-14
近年来,育种研究中应用通径分析日趋增 多,方法是利用性状间的遗传相关系数矩阵求 出原因性状(x)与结果性状(Y)间的直接遗传 通径系数(py.二),它反映了原因性状基因型值 对结果性状基因型值的直接作用。但由于选择 是对表现型进行的,考虑到选择对于表型值的 影响,采用相关遗传力的分析方法,就能将性状 (M=gzrB -, gv些p,)联系起来考虑,使基因型值 和表现型值更好地联系起来。求出性状(x)对 性状(力的直接相关遗传力(h.,hypy.二),就能找 出在其它性状不变的情况下,p二变化对于p,的 直接影响。为此,本文试图用此方法对小麦部 分性状参数予以估算,为产量育种提供一些参 考信息。  相似文献   

7.
钙和聚乙二醇浸种对小麦幼苗水分胁迫的缓和效应   总被引:6,自引:0,他引:6  
小麦(Triticumaestivum)品种PH82-2-2种子,用0.25%CaCl2和20%聚乙二醇(PEG6000)溶液(对照用无离子水)分别浸种18h后盆栽。盆栽上为研镶上,pH6.6,有机质含量1.1%,速效氮0.47mmol/L,速效磷0.18mmol/L,速效钾0.23mmol/L。施肥量为1kg拌入0.15g脲素、0.15  相似文献   

8.
为研究大鼠红细胞对葡萄糖利用的异头物选择性及其作用机制,应用大鼠红细胞,对葡萄糖的两种异头物作了异构化速率、乳酸生成量、内流速度和大鼠红细胞已糖激酶作用下的磷酸化速度等进行了测定.结果指出,37℃时大鼠红细胞的D-葡萄糖β-异头物和α-异头物代谢成乳酸的速度分别是0.27μmol/gHb(3min)和0.21μmol/gHb(3min),即前者快于后者30%.同时β-D-葡萄糖向红细胞内转运速度也快于后者:分别是5.0和3.5μmol/gHb(3min).大鼠红细胞已糖激酶的葡萄糖磷酸化速率实验结果指出:β-异头物比α-异头物快30%;对于该两种异头物已糖激酶的Km值均为53μmol/L.红细胞与α-和β-D-葡萄糖保温1min后,其葡萄糖浓度均达到1mmol/L左右,说明至少在1min内对于已糖激酶的磷酸化此两种异头物的葡萄糖浓度均已饱和.这些结果提示,大鼠红细胞葡萄糖利用的β-异头物优选性主要与其磷酸化速度有关,而与其转运速度关系不大.  相似文献   

9.
利用主成分分析、系统聚类分析和非参数检验,对采自北京地区的88只姬鼠标本(黑线姬鼠Apodemus agrarius除外)的10个形态分类指标进行了分析,以便确定出最具种问特异性的形态分类特征并给出定量判别标准.结果表明:除黑线姬鼠外,北京地区另有中华姬鼠(A.draco)和大林姬鼠(A.peninsulae)两种姬鼠;门齿孔后缘距上臼齿列前缘水平线的距离(x9)、上领M^1后内侧齿突向舌侧突出的程度(x1)及其与第2横嵴内侧齿突的相对大小(x2)是区分后两种姬鼠的最有效的形态分类指标;3个指标的种间界限大致为:中华姬鼠x9〈0.4mm,01≥0.2mm,x2≥0.6;大林姬鼠x9≥0.4mm,x1〈0.2mm,x2〈0.6.  相似文献   

10.
目的比较原代宁乡花猪与其第一代仔猪血液生理生化指标的变化。方法常规方法测定宁乡花猪F0代16头,F1代16头血液18项生理指标和13项生化指标。结果F0代与F1代部分血液生理指标如白细胞(WBC)、红细胞(RBC)、血红蛋白(HGB)、红细胞积压(HCT)等13项有显著性差异(P〈0.05);部分血液生化指标如总胆红素(TBIL),尿素氮(BUN),总蛋白(TP),白/球蛋白(ALB/GLB),葡萄糖(GLU),有显著性差异(P〈0.05);其他指标均无统计学差异。结论2代宁乡花猪之间部分血液生理生化指标有显著性差异。得到的数据可以为实验动物化研究提供相应的基础生理参考数据。  相似文献   

11.
Smaragdov MG 《Genetika》2011,47(1):126-132
The substitution of lysine for alanine (K232A) in the acyl-CoA-diacylglycerol acyltransferase, which is encoded by the DGAT1 gene, was tested for the significance for breeding evaluation of stud bulls of the holsteinized Black-and-White breed. The breeding value (deviation of milk productivity in daughters compared with cows of the same age) was estimated by the DYDC (daughter yield deviation to contemporary) method with modification. The frequency of allele 232K in the bulls examined was 0.28, lower than in Holstein bulls (0.4-0.6). The greatest effect of the A232K substitution was observed for the percent fat content in milk (1.4 sigma) and milk yield (0.76 sigma), and a lower effect was established for the milk protein yield (0.47 sigma) and percent protein content in milk (0.44 sigma). In the case of milk fat yield, the effect was nonsignificant. A method was proposed for converting the data on fat yield in order to obtain significant results in this case as well. The effect of the A232K substitution was estimated at 154 kg for milk yield, 2.8 kg for protein yield, 0.079% for percent fat content, and 0.015% for percent protein content. The results are discussed in the context of multiple pleiotropic effects of the K232A substitution in the DGAT1 gene. It is proposed that the K232A substitution of the DGAT1 gene be used as a golden standard in comparisons of the effect on milk productivity for the total gene set. This approach will allow a meta-analysis of the gene effects in spite of the differences in dairy cattle breeds and methods used to analyze their breeding value. In view of more than 30-year experience of using sperm of Holstein stud bulls, including those bred in North America, it was noted that the effect of the A232K substitution on milk productivity traits agreed well with the data reported for the North American commercial population of Holstein cattle.  相似文献   

12.
The aim of this study was to identify the presence of SNPs in the chemokine genes CCL2 and IL8 and the chemokine receptor genes IL8RA and CCR2, and assess their potential contribution to variation in estimated breeding values (EBVs) for somatic cell score (SCS) and four other traits in Canadian Holstein bulls. Pools of DNA for bulls with high (H) and low (L) EBVs for SCS were used for identification of 11 SNPs. Two unreported SNPs were found in the CCL2 gene and one SNP was found in the CCR2 gene. Previously reported SNPs (three in the IL8 gene and five in the IL8RA chemokine receptor) were also identified. Two SNPs in CCL2, three in IL8, one in IL8RA and one in CCR2 were genotyped in Canadian Holstein bulls (n = 338) using tetra primer ARMS-PCR. We investigated associations of these seven polymorphisms with three production traits (milk yield, fat yield and protein yield) and one conformation trait related to mastitis (udder depth). The allele substitution effect for the CCL2 rs41255713:T>C SNP was significant at an experimental-wise level for milk yield (247.5 +/- 79.9 kg) and protein yield (7.4 +/- 2.3 kg) EBVs (P T SNP on SCS was significant at the comparison-wise level (-0.04 +/- 0.02, P = 0.05), which might indicate a possible association in support of other published studies. Lastly, we assigned CCR2 to BTA22q24, where a previously QTL for SCS was identified.  相似文献   

13.
New molecular techniques focused on genome analysis, open new possibilities for more accurate evaluation of economiclly important traits in farm animals. Milk production traits are typical quantitative characteristics controlled by a number of genes. Mutations in their sequences may alter animal performance as well as their breeding values. In this study, we investigated the effect of Kpn2I restriction fragment length polymorphisms in the leptin gene, on bull breeding values for milk yield, fat, and protein yield, and their percentage. In order to test for an association between the leptin single-nucleotide polymorphism in exon 2 and milk productivity, we genotyped 134 Iranian Holstein bulls. Breeding values for milk-related traits (milk yield, fat, and protein yield and percentage) were estimated using the BLUP based on an animal model. The effect of the genotypes of Kpn2I polymorphism on the breeding values for milk-related traits was examined using least square methods. The T allele frequency was 0.425. Genotypes were distributed according to the Hardy-Weinberg equilibrium. Bulls with TT genotype had higher milk, fat and protein yield compared with TC and CC bulls (P < 0.05). Bulls with CC genotype had higher protein percentage compared with TT and TC bulls (P < 0.05). The association between leptin polymorphism with milk production traits suggests that this marker may be useful for selection based on molecular information.  相似文献   

14.
升马唐种群生态及其田间密度调控指标的研究   总被引:11,自引:3,他引:8       下载免费PDF全文
 研究表明,马唐的生育期为62—111天,需>0℃积温1380—2716。其生殖生长阶段对季节的温度要求严,营养生长阶段宽,生育期长短主要靠营养生长期的长短来调节。马唐种子休眠期一般为150天,休眠期长短和解除休眠速率与种子贮藏条件关系密切,以恒温贮藏最快。种子发芽起点温度为15℃,60%种子发芽的有效积温平均为555.13℃。马唐种子发芽对光照要求不敏感。在农田7cm土层内的种子均能出苗,但以1—4cm层最佳。马唐的再生能力强,试验表明,凡是带有须根和幼芽的任何断节都能发生新的植株。通径分析结果表明,马唐是我国北方夏播粮田的主要杂草。马唐群体水平(x,株/m2)与夏玉米籽粒减产率(y,%)间呈以下关系模式:(1)y=0.1532x1-5574(x≤20株/m2) (2)y=-18.400+11.315lnx(x>20株/m2)与夏玉米共同生长日数对作物籽粒减产率呈以下关系模式:y=54.5956/1+89.7962e-0.1184x根据推算,在石家庄地区夏播玉米田,马唐的允许存在密度即生态经济阈值为5.8株/m2。  相似文献   

15.
Swamp buffalo exhibited seasonal variations in daily sperm production and in daily sperm production per gram of testis parenchyma. Maximum rates occurred in the late wet season and early dry season. There was no spermatogenesis detected in 1-yr-old bulls. Daily sperm production per gram of testis parenchyma increased thereafter up to 3.5 yr of age, and was similar in all older age groups. Scrotal circumference in bulls of this age ranged from 20 to 21 cm. Scrotal circumference and daily sperm production increased rapidly up to maturity, and increased less rapidly thereafter. Mean+/-SEM daily sperm production per gram in 146 mature buffalo bulls was 14.04 x 10(6)+/-0.39 x 10(6) and mean+/-SEM daily sperm production was 1.86 x 10(9)+/- 0.07 x 10(9). Mean+/-SEM epididymal sperm reserves in adult bulls numbered 9.7 x 10(9) +/- 0.07 x 10(9). These were distributed between the caput, corpus and cauda epididymis in the proportions of 28.82, 14.63 and 60.55, respectively. Mean+/-SEM epididymal transit time was 5.65+/-0.24 d.  相似文献   

16.
4种生态因子对虎斑乌贼幼体生长与存活的影响   总被引:1,自引:0,他引:1  
旨在研究温度、盐度、饵料种类、投饵量对虎斑乌贼(Sepia pharaonis)幼体生长与存活率的影响,以确定其生长发育的最佳生态条件,为人工育苗提供理论依据。在室内控制条件下,采用单因子试验研究了不同温度(18、21、24、27、30和33℃)、不同盐度(18、21、24、27、30和33)、不同饵料种类(虾糜、活糠虾、卤虫无节幼体、桡足类、死糠虾、虾糜+强化卤虫后无节幼体、强化卤虫后无节幼体)、活糠虾不同投饵量(0、2、4、6、8和10 g/d)对虎斑乌贼幼体生长发育的影响。结果显示:不同温度对虎斑乌贼幼体生长影响显著(P〈0.05),最适温度为24-27℃,在最适温度下,存活率为84.4%-91.1%,特定生长率为4.82%-6.13%,存活率(y)与温度(x)的函数关系为y=-0.15x3+30.637x-447.002(r2=0.923)。幼体适宜盐度为24-33,最适盐度为27,在最适盐度条件下,其存活率为(90.0±5.29)%,特定生长率为(3.71±0.34)%。投喂7种开口饵料,以活糠虾效果最佳,存活率为(96.7±2.94)%,特定生长率为(3.77±0.23)%;强化卤虫后无节幼体效果次之,存活率为(95.6±2.31)%,特定生长率为(2.54±0.15)%,其余各组培养效果均不理想。投喂活糠虾,随着投饵量的增加,其存活率随之提高,摄食量(y)与个体重(x)的回归方程为y=0.227x-0.063(r2=0.921)。  相似文献   

17.
The substitution of lysine for alanine (K232A) in the acyl-CoA:diacylglycerol acyltransferase, which is encoded by the DGAT1 gene, was tested for the significance for breeding evaluation of bulls of the holsteinized Black-and-White breed. The breeding value was estimated by the DYDC (daughter yield deviation to contemporaries) method with modification. The frequency of allele 232K in the bulls examined was 0.28, lower than in Holstein bulls (0.4–0.6). The greatest effect of the A232K substitution was observed for the percent fat milk yield (1.4σ) and milk yield (0.76σ), and a lower effect was established for the milk protein yield (0.47σ) and percent protein milk yield (0.44σ). In the case of milk fat yield, the effect was nonsignificant. A method was proposed for converting the data on fat yield in order to obtain significant results in this case as well. The effect of the A232K substitution was estimated at 154 kg for milk yield, 2.8 kg for milk protein yield, 0.079% for percent milk fat, and 0.015% for percent milk protein yield. The results are discussed in the context of multiple pleiotropic effects of the K232A substitution in the DGAT1 gene. It is proposed that the K232A substitution of the DGAT1 gene may be used as a golden standard in comparisons of the effect on milk production traits for the total gene set. This approach will allow a meta-analysis of the gene effects in spite of the different dairy cattle breeds and methods used to analyze their breeding value. In view of more than 30-year experience of using sperm of Holstein bulls, including those breeds in North America, it was noted that the effect of the A232K substitution on milk production traits agreed well with the data reported for the North American commercial population of Holstein cattle.  相似文献   

18.
Twelve lactating Holstein cows in 2nd lactation were allocated randomly, six each, to two feeding treatments: high concentrate (1 kg dairy concentrate to 2 kg milk produced) and low concentrate (1 kg dairy concentrate to 4 kg milk produced) from 7 to 106 days postcalving. Forage and water were provided adalibitum. Milk and butter fat yields and rectal temperatures were examined in relation to 9 weather variables (minimum, maximum and mean temperatures, relative humidity, temperature-humidity index (THI), radiation, wind velocity and mean temperature of the previous day). Averages for milk yield, fat yield and rectal temperature were respectively 20.4 kg, 0.7 kg and 38.9°C for the high concentrate treatment and 18.4 kg, 0.6 kg and 38.6°C for the low concentrate treatment. Weather conditions accounted for 5.6%, 0.8% and 10.8% of the day to day variation in milk yield, fat yield and rectal remperature, respectively, for the high concentrate group and 29.4%, 9.7% and 0.6%, respectively, for the low concentrate group. Only measures of ambient temperature, especially mean temperature, were closely associated with these traits.  相似文献   

19.
Quantitative histological techniques were used to characterize the pattern of testicular and epididymal development in 42 Boran and 49 Boran x Friesian bulls aged between 6 and 23 mo. Bulls were divided into five age groups having four-month intervals. Between 6 and 23 mo of age, body weight increased from 124 to 293 kg and 179 to 267 kg (P<0.01) in Boran and Boran x Friesian bulls, respectively. Scrotal circumference measurements increased from 6 to 23 mo by 10.2 and 8.9 cm in Boran and Boran x Friesian bulls. Paired testes weight increased significantly (P<0.001) over the same period from 29 to 304 g and 59 to 291 g in Boran and Boran x Friesian bulls, respectively. Both caput and cauda epididymal segment weights also increased significantly (P<0.001) with age. There were significant (P<0.05) genotype differences in seminiferous tubule diameter, which increased by 137 and 90 mum with increasing age in Boran and Boran x Friesian bulls, respectively. Patent seminiferous tubules were first observed at 206 and 188 d of age in Boran and Boran x Friesian bulls, respectively. The appearance of elongated spermatids and spermatozoa in the seminiferous tubules and epididymal tubules occurred at later ages in Boran than in Boran x Friesian bulls.  相似文献   

20.
Daughter yield deviations (DYDs) of bulls and yield deviations (YDs) of cows, besides estimated breeding values (EBVs), are standard measures of animals' genetic merits in routine genetic evaluations worldwide. In this contribution, we first point out differences and similarities between DYDs and EBVs calculated for milk, fat and protein yields. While the latter measure represents the additive polygenic value of an animal, the former consists of both the additive polygenic and residual components. Then, a summary of DYDs and YDs calculated for the Polish population of dairy cattle is presented. The estimated correlations between DYDs and EBVs are generally high, but vary considerably depending on the minimum number of daughters used for calculation of DYDs and on the accuracy of calculated DYDs. Using DYDs estimated for each production year for 16 452 bulls, we demonstrate how to use DYDs for the validation of genetic trend estimated in the model used for genetic evaluation. Based on genotypic data of 252 bulls, we show that DYDs can be used for the estimation of candidate gene effects. For each of the yield traits, the within-bull genetic trend was relatively high, ranging between 1.39% of genetic standard deviation per production year for milk and 7.67% of genetic standard deviation per production year for fat, both in the 2nd lactation. Out of 8 polymorphisms tested, 5 showed a significant correlation with DYD, with the highest effect attributed to the polymorphism within the leptin receptor gene, whose additive effect was estimated as 247.33 kg of milk at 2nd parity.  相似文献   

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