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801.
AIM: To investigate two single nucleotide polymorphisms (SNP) in the apolipoprotein(a) promoter at positions -418 and -384 and to compare distributing difference of genotype frequencies of single nucleotide among different races and to explore the influencies of them on serum lipid level and their association with coronary heart disease (CHD). METHODS: Using PCR-RFLP (BsgI,BfaI) method, we determined genotypes of these two SNPs in 156 unrelated healthy controls of HanZu Chinese and 56 unrelated CHD patients of HanZu Chinese and 56 unrelated African Blacks, then cloned polymerase chain reaction (PCR) products into T-vector and sequenced it by M13 currency primer, correspondingly. RESULTS: (1) There was no polymorphism at position -418A/A and -384C/C in control group. Only one CHD patient's genotype determined was -418G/G, other were -418A/A and -384C/C in CHD patients. (2) Only two African Blacks' genotype determined was -418G/G, other were -418A/A and -384C/C in African Blacks. (3) However, the Apo(a) promoter sequence was in coincident with the sequence publicized in GenBank and the base at positions -418 was adenine (A) and -384 was cytosine (C). CONCLUSION: The mutation frequencies at position -418 and -384 were low in the Chinese Han Population of Hubei and perhaps no single nucleotide polymorphisms was at two positions. No association with serum lipid levels and CHD was observed. There were great variabilities to the SNPs in the Apo(a) promoter among different races.  相似文献   
802.
从体成分的角度研究了光照对内蒙古白绒山羊营养分配的影响。结果表明,光照对体成分有较大影响,随着光照时间的减少,体内干物质的含量增加,体脂肪含量增加。长光照、自然光照和短光照条件下绒山羊的体脂肪含量占干物质的比例分别为41.43%±0.41%、44.43%±0.16%和53.90%±1.70%,而体蛋白、体水分和体灰分含量则随着光照时间的缩短而减少,绒山羊血液中与营养分配有关的激素也发生较大的变化。研究证明光照在绒山羊营养分配中的调节作用,为其在生产实践中的合理应用提供理论依据。  相似文献   
803.
Linkage mapping of four chicken calpain genes   总被引:2,自引:0,他引:2  
Calpains are intracellular Ca2+‐dependent proteases and enzymes that contribute to growth and meat quality. In the present study, we identified polymorphisms in four calpain genes (CAPN1, CAPN2, CAPN3, and CAPN1.5) expressed ubiquitously in chicken using polymerase chain reaction‐restriction fragment length polymorphism, and mapped them using two backcross families (East Lansing (EL) and Kobe University (KU)). CAPN2 and CAPN1.5 mapped to two locations on chromosome 3 about 30 cM apart, while CAPN3 mapped to chromosome 5. CAPN1 was linked to a previously unlinked microsatellite marker LEI0140 to form a new linkage group called E66. CAPN2 and CAPN3 extend the amount of conserved synteny between chicken chromosome 3 and human chromosome 1, and between chicken chromosome 5 and human chromosome 15, respectively. Although CAPN2, CAPN3, and CAPN1.5 were found in the University of California Santa Cruz chicken genome browser gateway, CAPN1 and LEI0140 were not in specific genomic positions.  相似文献   
804.
差压相关法确定水平管段塞流液塞速度及长度   总被引:1,自引:0,他引:1  
分析了差压信号和波高信号之间的对庆关系,给出了利用差压信号求液塞速度的方法,提出了“假渡越时间”的新概念,根据这一概念给出了求液塞长度的方法,试验结果表明,该方法是求解液塞长度比较有效的一种方法。  相似文献   
805.
木材阻燃耐久性研究   总被引:2,自引:1,他引:1  
研究了PNB阻燃体系的阻燃耐久性问题。研究结果,试件在流动水中浸泡一天失重率为未浸泡前的7倍,有焰燃烧时间和无焰燃烧时间由零增加到180s和650s,损毁长度率为100%,与未经阻燃处理的试件相同。利用脲醛预缩液与PNB混合浸注木材,干燥处理后,在流动水中浸泡7嵦欤е芈始负趺挥斜浠醒嫒忌帐奔浜臀扪嫒忌帐奔浔3治悖鸹俪ざ嚷事杂性黾印K得麟迦┰に跻憾蕴岣咦枞继逑档目沽魇杂幸欢ㄗ饔茫瑣从而提高了木材阻燃的耐久性。  相似文献   
806.
张俊会  王谦 《中国食用菌》2005,24(5):49-50,61
以白灵侧耳为出发菌株,以葛根作为发酵基质中的中草药添加物,观察了葛根对白灵侧耳液体发酵的影响。果蝇寿命实验及体外抗氧化实验表明,葛根发酵产物较纯药及普通发酵物有更强的果蝇寿命延缓能力及抗氧化活性。  相似文献   
807.
Polymerase chain reaction (PCR) and polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) techniques were applied for establishing the reliable practice in identification of Echinochloa oryzicola Vasing. and E. crus-galli (L.) Beauv. (barnyardgrass). Total DNA was extracted from 18 accessions and 86 individuals of E. oryzicola , 33 accessions and 140 individuals of E. crus-galli var. crus-galli , 23 individuals of E. crus-galli var. praticola , and six individuals of E. crus-galli var. formosensis that were collected from Japan. A partial region of intergenetic spacer between trn T and trn L, and an intron of trn L were amplified separately using a trn-a and trn-b1 primer set, and a trn-c and trn-d primer set, respectively. All individuals of E. oryzicola showed the same fragment amplified by the trn-a and trn-b1 primer set. The fragment was 481 bp in length, and was undigested by Eco R I, whereas all individuals of E. crus-galli , including three botanical varieties, showed the same fragment with a 449-bp length. The fragment was digested by Eco R I into two fragments (178 and 271 bp). The fragment amplified by the trn-c and trn-d primer set in all individuals of E. oryzicola was digested by Alu I into two fragments (174 and 452 bp), but undigested by Dra I. In contrast, the fragment amplified by the trn-c and trn-d primer set in all individuals of E. crus-galli was digested by Dra I into two fragments (134 and 487 bp), but undigested by Alu I. There was no intraspecific variation in these regions; thus, these two species are easily identifiable by using our method.  相似文献   
808.
獭兔小肠组织形态发育规律研究   总被引:2,自引:0,他引:2  
对相同条件下饲养的不同生长阶段(出生、1周龄、2周龄、3周龄4、周龄、5周龄、6周龄、8周龄、12周龄、成年)獭兔进行屠宰,观察测定肠道绒毛和腺窝变化,以研究獭兔消化组织形态的发育规律。结果表明:獭兔小肠绒毛长度随周龄的增加而增加。断奶刺激降低绒毛长度,但断奶1周后基本恢复。石蜡切片观察发现獭兔小肠绒毛形态为指状。  相似文献   
809.
The objective of the study was to describe the effects of carbon dioxide pneumoperitoneum and Trendelenburg position on arterial blood gas values in horses anesthetized for laparoscopy. The study design was a prospective case series using 14 healthy adult horses anesthetized for elective laparoscopic surgery. All horses in the study were maintained under anesthesia with halothane in oxygen with intermittent positive-pressure ventilation. A pneumoperitoneum of 15 mmHg or less was achieved with carbon dioxide, and horses were tilted to a 35-degree Trendelenburg position to allow the completion of laparoscopic cryptorchidectomy (n = 13) or ovariectomy (n = 1). Heart rate, mean arterial pressure, and arterial blood gases were recorded at six time intervals throughout the procedure. Results of the study indicated a pH that decreased and partial pressure of carbon dioxide (PaCO2) and mean arterial pressure that increased over time and differed significantly from baseline during Trendelenburg position. Partial pressure of oxygen (PaO2) was significantly lower than baseline after assumption of Trendelenburg position and did not improve on return to normal recumbency and abdominal pressure. As body weight increased, pH and PaO2 decreased and PaCO2 increased. We concluded that horses placed in Trendelenburg position have changes that are transient, with the exception of PaO2. Heavier horses have a greater change in pH, PaCO2, and PaO2 than lighter horses during abdominal insufflation and Trendelenburg position. The changes incurred during CO2 abdominal insufflation and Trendelenburg position are transient, with the exception of a decreased PaO2. Heavy horses undergoing abdominal insufflation and Trendelenburg position should be closely monitored for critical cardiopulmonary values.  相似文献   
810.
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