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1.
A primary driver of the wheat yield gap in Australia and globally is the supply of nitrogen (N) and options to increase N use efficiency (NUE) are fundamental to closure of the yield gap. Co‐application of N with phosphorus (P) is suggested as an avenue to increase fertiliser NUE, and inputs of N and P fertiliser are key variable costs in low rainfall cereal crops. Within field variability in the response to nutrients due to soil and season offers a further opportunity to refine inputs for increased efficiency. The response of wheat to N fertiliser input (0, 10, 20, 40 and 80 kg N ha‐1) under four levels of P fertiliser (0, 5, 10 and 20 kg P ha?1) was measured on three key low rainfall cropping soils (dune, mid‐slope and swale) across a dune‐swale system in a low rainfall semi‐arid environment in South Australia, for three successive cropping seasons. Wheat on sandy soils produced significant and linear yield and protein responses across all three seasons, while wheat on a clay loam only produced a yield response in a high rainfall season. Responses to P fertiliser were measured on the sandy soils but more variable in nature and a consistent effect of increased P nutrition leading to increased NUE was not measured.  相似文献   
2.
对人和哺乳动物支气管动脉与肺动脉吻合问题的研究进行了概述.肺动脉与支气管动脉吻合的意义在于支气管动脉的高氧血液可以进入肺动脉代偿供应肺泡组织,肺动脉的营养血液也可以进入支气管动脉代偿供应肺间质.肺动脉与支气管动脉之间血管吻合常可以发生在胸膜面、支气管壁、终末细支气管或呼吸性细支气管等部位,也可以在毛细血管上发生支气管动脉与肺动脉的吻合.根据血管吻合的长度和口径,将其分为长吻合型和短吻合型,按照血管吻合的方式分为端-端吻合和端-侧吻合.在某些病理情况下,肺动脉与支气管动脉之间的吻合支还会通过管径扩张,增加血流量来供应局部的病变组织,因此有利于防御不利因素对机体造成的损伤,为机体实施正常的呼吸功能提供保障.  相似文献   
3.
The comparison of the histologic healing and bronchopleural fistula (BPF) complications encountered with three different BS closure techniques (manual suture, stapler and manual suture plus tissue flab) after pneumonectomy in dogs was investigated for a one-month period. The dogs were separated into two groups: group I (GI) (n = 9) and group II (GII) (n = 9). Right and left pneumonectomies were performed on the animals in GI and GII, respectively. Each group was further divided into three subgroups according to BS closure technique: subgroup I (SGI) (n = 3), manual suture; subgroup II (SGII) (n = 3), stapler; and subgroup III (SGIII) (n = 3), manual suture plus tissue flab. The dogs were sacrificed after one month of observation, and the bronchial stumps were removed for histological examination. The complications observed during a one-month period following pneumonectomy in nine dogs (n = 9) were: BPF (n = 5), peri-operative cardiac arrest (n = 1), post-operative respiratory arrest (n = 1), post-operative cardiac failure (n = 1) and cardio-pulmonary failure (n = 1). Histological healing was classified as complete or incomplete healing. Histological healing and BPF complications in the subgroups were analyzed statistically. There was no significant difference in histological healing between SGI and SGIII (p = 1.00; p > 0.05), nor between SGII and SGIII (p = 1.00; p > 0.05). Similarly, no significant difference was observed between the subgroups in terms of BPF (p = 0.945; p > 0.05). The results of the statistical analysis indicated that manual suture, stapler or manual suture plus tissue flab could be alternative methods for BS closure following pneumonectomy in dogs.  相似文献   
4.
夏文睿  刘姣  胡艳平等 《安徽农业科学》2014,(11):3179-3181,3215
[目的]了解MeCWINCV5在植物生长发育、激素调节和逆境胁迫应答中的功能.[方法]采用PCR方法从木薯基因组中分离MeCWINCV5基因启动子序列,考察MeCWINCV5对植物生长发育、激素调节和逆境胁迫应答的影响.[结果]分析显示启动子的长度为1170bp,合有TATA box和CAAT box等多个典型的真核生物启动子基本元件元件,还存在大量逆境胁迫诱导相关的顺式调控元件,如HSE、MBS、SARE、GARE-motif和TATC-box等多个与植物逆境胁迫相关的元件.[结论]MeCWINCV5基因启动子与逆境胁迫有关,在木薯抵御逆境胁迫的生理过程中具有重要作用.  相似文献   
5.
目的:探讨慢性阻塞性肺疾病(COPD)的气道反应性IL-8因子在COPD发病中的作用,方法:用组胺气道吸入激发试验观察缓解期COPD,哮喘和健康人的气道反应性,同时测定气道激发前后血清IL-8水平变化。结果:COPD和哮喘患者均呈气道高反应性,且COPD组PD50FEV1与FEV1/Pre%(P〈0.02,P〈0.05),IL-8水平与PD20FEV1无显著相关性,气道激发后,COPD和哮喘血清I  相似文献   
6.
【目的】改进和优化ABS血管铸型技术。创建猪支气管动脉立体标本的铸型方法,并构建猪支气管动脉立体标本。为探明猪支气管动脉在肺内的分支与分布状态提供实验方法。【方法】用改进和优化ABS铸型技术,采用支气管动脉单纯铸型和支气管动脉与支气管树或肺动脉联合铸型的方法构建猪支气管动脉的立体标本。【结果】(1)创建了猪支气管动脉立体标本的铸型方法。①猪肺支气管动脉单纯标本制作的方法要点:先分别在胸主动脉近心端和远心端插管并结扎胸主动脉。同时,为了防止在灌入铸型剂时经食管和气管周围的血管网发生渗漏,分别在胸主动脉插管处相应的位置结扎食管前端和后端,并在气管开口处插入盲端套管并结扎。然后调整肺的位置,使其背上腹下地置于解剖盘中。经胸主动脉间接向支气管动脉中注入铸型剂。灌注时强压梯度灌入60 mL 10%和100-160 mL 15%的ABS铸型剂,当橡胶管中间部位膨大后停止灌注。在连续灌注结束后5 h内随时观察橡胶管膨大部位的大小,当压力减小时,立即灌入20%的ABS铸型剂,保证主动脉内的正压力。将灌注好的标本置于冷水中静态硬化3-4 d,再用盐酸密闭腐蚀10 d左右。然后用流水漂浮和加压冲洗,再通过摘除凝块、打枝疏密和断枝再植修整后就可以获得完整的铸型标本。②猪肺支气管动脉与支气管树联合铸型标本制作的方法要点:首先,同时插管并结扎胸主动脉、食管和气管。然后经胸主动脉间接灌注铸型剂。间隔1-2 h后再对气管树进行灌注。最后同步硬化、腐蚀、冲洗和修复支气管动脉与支气管树联合标本。③猪肺支气管动脉与肺动脉联合铸型标本制作的方法要点:支气管动脉与支气管树联合铸型的方法和支气管动脉与肺动脉联合铸型的方法相似,不同之处在于在将铸型剂注入支气管动脉的同时,前者是将铸型剂注入支气管树内,后者则是将铸型剂注入肺动脉内。在联合铸型时,根据肺的大小确定注入铸型剂的量,而经支气管动脉单纯铸型时,则根据压力大小确定灌注量。(2)构建了猪支气管动脉立体标本、猪支气管动脉与猪支气管树的联合立体标本和猪支气管动脉与肺动脉的联合标本。【结论】采用该方法获得的支气管动脉立体标本血管层次清楚、管道充盈光滑、对比度清晰,能够完整显示猪支气管动脉的起源、分支、走向、分布以及与支气管树和肺动脉的毗邻关系。该工作为猪及其它动物支气管动脉的研究奠定了基础。  相似文献   
7.
A 24-year-old, Thoroughbred gelding presented with difficulty breathing for a few days and intermittent nose bleeding before dying. At necropsy, the bronchoesophageal artery and the bronchial artery that flowed into the left anterior lobe were tortuous and dilated, and it was found that dilated tortuous branches of the bronchial artery ran over the dorsal and ventral surfaces of the left anterior lobe. Histopathologically, an anastomosis between a muscular artery and an elastic artery were demonstrated, which were identified as bronchial and pulmonary arteries, respectively. Based on the gross and histopathological findings, a bronchopulmonary artery fistula was diagnosed. To the best of our knowledge, this is the first case report of a pulmonary vascular anastomosis in a horse.  相似文献   
8.
AIM:To investigate the effect of oxidized α1-antitrypsin (Ox-AT) on interleukin 8 (IL-8) and monocyte chemotactic protein 1(MCP-1) production in cultured human bronchial epithelial (HBE) cells. METHODS:Plasma native α1-antitrypsin (N-AT) was purified from human plasma by 50% and 75% ammonium sulfate fractionation followed by glutathione and anion exchange chromatography. Ox-AT was prepared by incubating N-AT (0.5 g/L) with N-chlorosuccinimide in a 25-fold molar excess to N-AT in PBS at room temperature for 30 min. HBE cells were cultured in the presence of Ox-AT (0.5 g/L) for 4 h, 10 h and 24 h, and the levels of IL-8 and MCP-1 in the supernatant were assayed using respective DuoSet kits. The effect of NF-κB inhibitor Bay11-7082 on the inflammatory cytokine release induced by Ox-AT was also evaluated. RESULTS:Ox-AT concentration-dependently and time-dependently increased the production of IL-8 and MCP-1 in HBE cells. The concentrations of IL-8 and MCP-1 in HBE cells induced by 0.5 g/L Ox-AT at 4 h, 10 h and 24 h were significantly higher than those in blank control and N-AT groups. Ox-AT increased the activity of NF-κB in a dose-dependent manner. The proinflammatory effect of by Ox-AT was inhibited by NF-κB inhibitor Bay11-7082. CONCLUSION: Ox-AT is a strong proinflammatory factor for HBE cells. The mechanism is related to NF-κB signaling pathway activation.  相似文献   
9.
NAC转录因子是植物特有的一类转录调控因子,在植物的生长发育、激素调节和境胁迫应答中具有重要的功能。为研究NAC转录因子在巴西橡胶树(Hevea brasiliensis)抗逆胁迫中的功能,本项目组根据巴西橡胶树NAC转录因子-HbNAC1基因序列,通过Genome Walking方法从巴西橡胶基因组DNA中获得了长度为1861bp的HbNAC1基因的5'调控区片段,序列分析表明该段序列含有一个典型的真核生物核心启动子区域,转录起始位点T位于起始密码子上游52bp处。该启动子序列除了含有TATA-box、CAAT-box等基本顺式作用元件外,还具有茉莉酸响应元件以及大量光顺式作用元件和逆境胁迫诱导相关的顺式调控元件,这表明HbNAC1基因在橡胶树逆境胁迫应答过程具有重要功能,其启动子可能是一个光诱导型和组织特异性启动子。  相似文献   
10.
Endothelin-1 (ET-1), a physiological as well as an inflammatory mediator, causes contraction of airway smooth muscles by binding to endothelin-A (ETA) and endothelin-B (ETB) receptors. We investigated the interaction between endothelin receptors on contractions and oxidative stress of bronchial rings of clinically healthy horses. Rings for response studies were set in tissue chambers containing oxygenated Tyrode’s solution. Concentration-response relationships were determined for ET-1 on control rings, rings incubated with ETA antagonist (BQ123), rings incubated with ETB antagonists (IRL 1038 and BQ788), and rings incubated with all antagonists combined. For oxidative stress studies, rings were incubated for 30 minutes separately with ET-1, ETA antagonist + ET-1, ETB antagonists + ET-1, and all three antagonists + ET-1. The control rings were not treated with any agents. Electron paramagnetic resonance (EPR) method was used to measure total reactive oxygen species (ROS), superoxide, and peroxynitrite. Results showed that ET-1 caused dose-dependent contractions which were increased by ETA blockade and decreased by ETB blockade. Combined blockade significantly inhibited the response to ET-1. Regarding the oxidative stress, ET-1 and its antagonists significantly reduced the total ROS. Superoxide production was significantly decreased by ETA antagonist and completely abolished when ETA and ETB antagonists were combined. Peroxynitrite production was not changed significantly. The study suggested that an interaction between ET receptors exists in the expression of contractile responses and oxidative stress. ET-1 attenuated oxidative stress by decreasing total ROS. ETA receptors may be primarily responsible for superoxide production. It appears that ET-1 does not affect peroxynitrite production in normal equine tissues.  相似文献   
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