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71.
Xu  Lulu  Hao  Zhiqiang  Lin  Jinyan  Zhao  Qiong  Zhang  Baojun  Li  Guanglin  He  Jianping  Li  Jingang 《Molecular biology reports》2019,46(6):5671-5683
Molecular Biology Reports - With the increase in blood viscosity, the blood circulation resistance will increase when animals are in hypoxia. However, these phenomenons do not appear in...  相似文献   
72.
We recently demonstrated that treatment with the 5-HT(1A/7) receptor agonist [(R)-(+)-8-hydroxy-2-di-n-propylamino]tetralin (8-OH-DPAT) increases bladder capacity in chloralose-anesthetized female cats with chronic spinal cord injury. In the current study, we investigated the effects of 8-OH-DPAT on bladder capacity and external urethral sphincter (EUS) activity in urethane-anesthetized female rats (initial body mass 175-200 g) with chronic spinal cord injury (transsection at T10). Cystometric study took place 8-12 wk posttranssection. Intravesical pressure was monitored in urethane-anesthetized rats with a transvesical catheter, and EUS activity was assessed electromyographically. Spinal cord injury disrupts phasic activity of the EUS, resulting in decreased voiding efficiency and increased residual volume. 8-OH-DPAT induced a dose-dependent decrease in bladder capacity (the opposite of its effect in chronic spinal cord-injured cats) with an increase in micturition volume and decrease in residual volume resulting from improvement in voiding efficiency. The unexpected improvement in voiding efficiency can be explained by the 8-OH-DPAT-induced emergence of phasic EUS relaxation. Phasic EUS relaxation was also altered by 8-OH-DPAT in spinally intact rats, whereas the 5-HT(1A) receptor antagonist N-tert-butyl-3-[4-(2-methoxyphenyl)-piperazin-1-yl]-2-phenylpropanamide (WAY-100635), on its own, was without effect. It remains to be determined when phasic relaxation is restored after spinal cord injury, and indeed whether it is ever truly lost or is only temporarily separated from excitatory input.  相似文献   
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74.
对油桐尺蠖单粒包埋核型多角体病毒(Buzura suppressaria single-nucleocapsid nucleopolyhedrovirus, BusuNPV)基因组中BamHI-H片段的序列进行分析,该片段全长2 422 bp,包括三个开放阅读框:p47基因(AcMNPV ORF40的同源区)的5′端,完整的组织蛋白酶基因(cathepsin)(AcMNPV ORF127的同源区)和p74基因(AcMNPV ORF138的同源区)的3′端.序列比较分析表明,BusuNPV的这三个基因与其它杆状病毒的同源基因具有相同的结构保守区.BusuNPV基因组BamHI-H片段上这三个基因的排列顺序完全不同于AcMNPV相应基因的排列顺序.  相似文献   
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76.
Wheat scab (Fusarium Head Blight, FHB) is a destructive disease in the warm and humid wheat-growing areas of the world. Finding diverse sources of FHB resistance is critical for genetic diversity of resistance for wheat breeding programs. Leymus racemosus is a wild perennial relative of wheat and is highly resistant to FHB. Three wheat- L. racemosus disomic addition (DA) lines DA5Lr#1, DA7Lr#1 and DALr.7 resistant to FHB were used to develop wheat- L.racemosus translocation lines through irradiation and gametocidal gene-induced chromosome breakage. A total of nine wheat-alien translocation lines with wheat scab resistance were identified by chromosome C-banding, GISH, telosomic pairing and RFLP analyses. In line NAU614, the long arm of 5Lr#1 was translocated to wheat chromosome 6B. Four lines, NAU601, NAU615, NAU617, and NAU635, had a part of the short arm of 7Lr#1 transferred to different wheat chromosomes. Four other lines, NAU611, NAU634, NAU633, and NAU618, contained translocations involving Leymus chromosome Lr.7 and different wheat chromosomes. The resistance level of the translocation lines with a single alien chromosome segment was higher than the susceptible wheat parent Chinese Spring but lower than the alien resistant parent L. racemosus. At least three resistance genes in L. racemosus were identified. One was located on chromosome Lr.7, and two could be assigned to the long arm of 5Lr#1 and the short arm of 7Lr#1.  相似文献   
77.
为探究酸性矿山排水生态系统不同环境中的微生物群落和功能,全面了解酸性矿山排水的形成和发展规律,采用高通量测序技术研究云南省蒙自某矿区酸矿水坑和周边溪水中的原核微生物群落组成,并结合样本理化特征分析影响群落结构的主要因素,进而解析菌群的环境功能。研究发现酸矿水坑中主要有广古菌门、变形菌门(包括α、γ和δ变形菌纲)、硝化螺菌门、厚壁菌门、放线菌门和酸杆菌门等类群,与周边溪水的群落结构具有明显差异。群落多样性与pH呈显著正相关,而热原体纲(Thermoplasmata)与pH呈负相关,可对群落结构起主导作用。酸矿水坑不同样本中均具有高丰度的亚铁原体属Ferroplasma (6.60%–86.34%),酸硫杆菌属Acidithiobacillus是酸矿水和沉积泥中主要的铁、硫氧化细菌,而专性铁氧化的钩端螺旋菌属Leptospirillum的丰度较低,铁卵形菌属Ferrovum几乎只存在于酸矿水中;此外,嗜酸或耐酸的异养菌广泛分布于酸矿水和沉积泥中,它们可促进铁、硫氧化菌的生长及催化矿石溶解。结果表明,pH通过影响微生物多样性和菌群分布而对酸性矿山排水环境微生物群落结构造成重大影响。  相似文献   
78.
干热河谷冲沟沟岸葛藤不同覆被状况及土壤性质差异分析   总被引:3,自引:0,他引:3  
校亮  熊东红  张宝军  张素  吴汉  杨丹 《生态学报》2018,38(14):5047-5055
沟岸是干热河谷冲沟系统中土壤生态环境最为恶劣的地带,其水热矛盾突出、土层浅薄、土壤贫瘠。探讨葛藤覆被对沟岸土壤性质的影响,可为沟岸土壤改良与植被恢复奠定基础。以元谋干热河谷区葛藤覆被的冲沟沟岸为研究对象,选取裸露地块作为对照(CK),根据藤本生物量设置4个处理(T1:309.70 g/m~2鲜被物,T2、T3、T4:594.34、1103.43、1693.27 g/m~2枯落物),对比研究了葛藤不同覆被状况对沟岸土壤性质的影响。结果表明:沟岸土壤性质受葛藤覆被类型(鲜/枯)及生物量共同影响。(1)较裸露沟岸(11.05%),枯藤覆被有益于保持其下土壤水分(13.30%—18.90%),鲜藤覆被下土壤水分则明显降低(7.36%);较裸露沟岸,鲜、枯藤覆被均有助于增加其下土壤毛管孔隙度。(2)较裸露沟岸,鲜藤覆被下沟岸土壤有机质、铵态氮、硝态氮、有效磷、速效钾含量大都呈现出不同程度的降低,枯藤覆被沟岸上述土壤养分含量则整体增加,且大都呈现出随枯藤覆被量增加而增加的规律。(3)较裸露沟岸(3.24 nmol/g),鲜、枯藤覆被沟岸土壤总PLFA(总磷脂脂肪酸量Phospholipids fatty acid)量明显提升,T1—T4处理土壤的总PLFA量分别为裸露沟岸的10.5、2.6、2.6倍和6.5倍。研究成果对于干热河谷冲沟系统退化土壤的改良及植被恢复具有重要的指导意义。  相似文献   
79.
Rhamnolipid as a potent natural biosurfactant has a wide range of potential applications, including enhanced oil recovery (EOR), biodegradation, and bioremediation. Rhamnolipid is composed of rhamnose sugar molecule and beta-hydroxyalkanoic acid. The rhamnosyltransferase 1 complex (RhlAB) is the key enzyme responsible for transferring the rhamnose moiety to the beta-hydroxyalkanoic acid moiety to biosynthesize rhamnolipid. Through transposome-mediated chromosome integration, the RhlAB gene was inserted into the chromosome of the Pseudomonas aeruginosa PAO1-rhlA(-) and Escherichia coli BL21 (DE3), neither of which could produce rhamnolipid. After chromosome integration of the RhlAB gene, the constitute strains P. aeruginosa PEER02 and E. coli TnERAB did produce rhamnolipid. The HPLC/MS spectrum showed that the structure of purified rhamnolipid from P. aeruginosa PEER02 was similar to that from other P. aeruginosa strains, but with different percentage for each of the several congeners. The main congener (near 60%) of purified rhamnolipid from E. coli TnERAB was 3-(3-hydroxydecanoyloxy) decanoate (C(10)-C(10)) with mono-rhamnose. The surfactant performance of rhamnolipid was evaluated by measurement of interfacial tension (IFT) and oil recovery via sand-pack flooding tests. As expected, pH and salt concentration of the rhamnolipid solution significantly affected the IFT properties. With just 250 mg/L rhamnolipid (from P. aeruginosa PEER02 with soybean oil as substrate) in citrate-Na(2)HPO(4), pH 5, 2% NaCl, 42% of oil otherwise trapped was recovered from a sand pack. This result suggests rhamnolipid might be considered for EOR applications.  相似文献   
80.
测定了皱肋文蛤(Meretrix lyrata)软体部分的氨基酸含量与脂肪酸组成.共检出17种氨基酸,总含量为软体部干重的52.26%;4种呈味氨基酸(天门冬氨酸、谷氨酸、甘氨酸和丙氨酸)的含量为22.07%,占氨基酸总量的42.23%;必需氨基酸(EAA)总含量为20.72%,其必需氨基酸的构成比例基本符合FAO/W...  相似文献   
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