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991.
Yumei He Kaizhi Xie Peizhi Xu Xu Huang Wenjie Gu Fabao Zhang Shuanhu Tang 《Research in microbiology》2013,164(2):189-198
The composting of organic material is dependent on microbial activity. However, the dynamics of the microbial community during the composting process remain obscure. Here, denaturing gradient gel electrophoresis of 16S rDNA amplicons in a chicken manure-based compost was applied to characterize the components of the microbial community during the composting process. In addition, the activity of key microbial enzymes was monitored. Arcobacter spp. and Marinospirillum spp. were the dominant species prior to composting, whereas Thermotogae spp. became more strongly represented as the composting process proceeded. Bacillus and Cohnella spp. were featured at various phases. Correlation analysis showed that the diversity of the microbial community was positively correlated with the compost pH, its total nitrogen level, its carbon-to-nitrogen ratio and the activity of protease, and negatively correlated with its organic carbon content and seed germination indices. 相似文献
992.
角膜基质环植入术(ICRS)是一种用于治疗轻中度圆锥角膜的手术方法。ICRS是通过植入基质环,使中央角膜扁平化,弧长缩短,角膜曲率半径增大,屈光力降低,从而改善角膜前突导致的轴性近视眼与不规则散光。ICRS具有微创性、安全性、有效性、可逆性且并发症少等优点,其中长期疗效较佳。本文中笔者就ICRS的发展史、适应症、手术方法、手术疗效的影响因素、术后处理及疗效的评估等方面进行阐述。 相似文献
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995.
L. Guo W. Xie Y. Liu Z. Yang X. Yang J. Xia S. Wang Q. Wu Y. Zhang 《Insect molecular biology》2018,27(5):620-632
Bemisia tabaci (Gennadius) is an important agricultural pest with a worldwide distribution. Although B. tabaci is known to have a unique haplodiploid reproductive strategy, its sex determination mechanism is largely unknown. In this study, we cloned the full‐length sequence of B. tabaci doublesex (Btdsx) and found that Btdsx has 28 splicing isoforms. We found two new splicing isoforms of transformer 2 (Bttra2), which encode two proteins. We also confirmed that both genes lack sex‐specific splicing isoforms. Real‐time quantitative PCR analysis showed that the expression of Btdsx and Bttra2 is higher in males than in females. RNA interference of Bttra2 affected the expression of Btdsx and vice versa. Furthermore, silencing of Bttra2 or Btdsx caused malformation of the male genitalia (anal style). It did not affect the female phenotype, but reduced the expression of vitellogenin gene in females. These results indicate that Btdsx is associated with sex determination in B. tabaci and that Btdsx and Bttra2 affect each other and are important for male genitalia formation. In addition to increasing our understanding of the roles of dsx and tra2 in the sex determination of B. tabaci, the results will be useful for studies of sex determination in other haplodiploid species. 相似文献
996.
Xiang Cong Tham Huiting Xie Cecilia Mui Lee Chng Xin Yi Seah Violeta Lopez Piyanee Klainin-Yobas 《Archives of Psychiatric Nursing》2018,32(4):536-548
Schizophrenia is a mental disorder, which is marked by frequent relapses. The main reason for relapse is nonadherence to antipsychotics. A cross-sectional, correlational research study was conducted with a convenience sample of 92 participants. The primary aim of this study was to explore the predictors of medication adherence among inpatients with schizophrenia hospitalised at tertiary hospitals in Singapore. Post-hoc analysis revealed that insight, religion, side effects, types of antipsychotics, social support from significant others, nurse-client relationship, were significant predictive factors. Results from this study added knowledge to the nursing literature about medication adherence of schizophrenia patients and in Singapore setting. 相似文献
997.
RNA interference unveils the importance of Pseudotrichonympha grassii cellobiohydrolase,a protozoan exoglucanase,in termite cellulose degradation
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Based on prior work, a cellulase from glycosyl hydrolase family 7 (GHF7) was identified and found to be expressed at a high level in Coptotermes formosanus. To determine the function of GHF7 family members in vivo, we used RNA interference (RNAi) to functionally analyse the exoglucanase gene Pseudotrichonympha grassii cellobiohydrolase gene (PgCBH), which was highly expressed in Pseudotrichonympha grassii, a flagellate found in the hindgut of C. formosanus. In this study, the expression level of PgCBH was down‐regulated by RNAi, causing the death of P. grassii, but no effect was observed for other flagellates found in C. formosanus. RNAi also resulted in significantly reduced exoglucanase activity, and no effect was observed for endoglucanase and β‐glucosidase activities. This result demonstrated that the PgCBH gene plays a role in the protist lignocellulolytic process and is also important for host survival. PgCBH can be used as a target gene and has potential as a bioinsecticide for use against termites. 相似文献
998.
Bin-Shan Zha Hua-Gang Zhu Yu-Sheng Ye Yong-Sheng Li Zhi-Gong Zhang Wen-Tao Xie 《Cardiovascular and interventional radiology》2017,40(3):455-459
Thoracic aortic aneurysms are now routinely repaired with endovascular repair if anatomically feasible because of advantages in safety and recovery. However, intraoperative aneurysm rupture is a severe complication which may have an adverse effect on the outcome of treatment. Comprehensive preoperative assessment and considerate treatment are keys to success of endovascular aneurysm repair, especially during unexpected circumstances. Few cases have reported on intraoperative aortic rupture, which were successfully managed by endovascular treatment. Here, we present a rare case of an intraoperative aneurysm rupture during endovascular repair of thoracic aortic aneurysm with narrow neck and angulated aorta arch (coarctation-associated aneurysm), which was successfully treated using double access route approach and iliac limbs of infrarenal devices. Level 5. 相似文献
999.
目的探讨75岁以上高龄老年房颤患者的栓塞及出血风险及目前本院的抗栓治疗现状。方法根据2010年欧洲心脏病学会《房颤治疗指南》中的CHA2DS2.VASe评分标准和HAS.BLED评分标准,对2011年3月-2011年9月在我院老年医疗科病房明确诊断存在心房纤颤、且年龄I〉60岁的老年患者分成〈75岁(老年组)和〉175岁(高龄老年组)两组,对两组患者的相关资料进行对照分析。结果高龄老年组的CHA2DS2-VASe评分(5.65±1.12)和HAS-BLED评分(3.60±0.84)均显著高于老年组(分别为3.55±1.15和2.85±0.81);两组的抗栓治疗的比例均较低,且有显著差异(51.28%vs62.34%)。结论年龄〉75岁的高龄老年房颤患者存在极高的栓塞及出血双重风险,抗栓治疗的实施率也显著降低。对该类人群的治疗必须依托安全有效的抗栓策略,以改善目前的治疗现状。 相似文献
1000.
Design,synthesis and biological evaluation of novel quinoline [4,3-b]chromene derivatives as AChE inhibitors through an efficient one-pot,four-component microwave-mediated reaction
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An efficient synthesis of chromeno[4,3-b]quinoline derivatives via one-pot, four-component reaction of 4-hydroxycoumarin, formaldehyde, cyclohexanedione, ammonium ceric nitrate under microwave irradiation was accomplished. The structures of these compounds were unambiguously confirmed by single crystal X-ray diffraction. Furthermore, the anti-AChE activities of these compounds in vitro were investigated at concentrations of 20 μM and 50 μM by using a standard Ellman’s method. The relationship of inhibitory activities and structures of these chromeno [4,3-b]quinolines was also systematically studied. Of all the compounds investigated, 4ag emerged as the most potent AChE inhibitor with IC50 values of 5.63 µM, and it might be used as potent lead for the development anti-AChE agents. Moreover, molecular modelling was conducted to understand the optimal interaction of AChE with these types of compounds. 相似文献