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91.
黑曲霉Aspergillus niger因能够产生大量的木质纤维素降解酶而在木质纤维素资源利用中发挥重要作用。目前,有关黑曲霉基因组中与木质纤维素降解相关的基因是否存在可变剪接的情况尚不清楚。本研究以黑曲霉CBS513.88菌株为研究对象,采用rMATS和ABLas两种方法对黑曲霉在葡萄糖为唯一碳源(G组)和小麦秸秆为唯一碳源(WS组)下的56个木质纤维素降解酶基因的可变剪接事件进行分析,并通过RT-PCR扩增和内含子特异性扩增对3个典型基因的可变剪接体进行了验证。结果表明,ABLas可变剪接分析算法相较于rMATS分析算法更为准确,ABLas分析算法显示G组和WS组共有21个木质纤维素降解酶基因出现了可变剪接,可变剪接类型以内含子保留(IR)为主,占所有可变剪接事件的82.85%。另外,G组和WS组发生可变剪接的木质纤维素降解酶基因也有所不同:G组发生可变剪接的基因为13个,WS组发生可变剪接的基因为14个,两组都发生可变剪接的基因为6个,这表明黑曲霉木质纤维素降解酶基因的可变剪接在不同生长条件下存在差异,另一方面,黑曲霉中众多可变剪接体的存在也为开发新型的木质纤维素降解酶资源提供基础。 相似文献
92.
彩色豆马勃Pisolithus tinctorius可广泛与林木建立外生菌根,其共生可促进植物生长,提高植物对重金属的耐受性。然而,关于彩色豆马勃对重金属锌(Zn)胁迫的生理响应还不完全清楚。本研究在纯培养条件下,测定了Zn胁迫对彩色豆马勃生物量、Zn的活性形态和亚细胞分布,超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性,谷胱甘肽(GSH)、抗坏血酸(AsA)和黑色素含量的影响。结果表明,Zn胁迫抑制了彩色豆马勃的生长,在浓度为563 μmol/L时,达到半数最大抑制浓度(IC50),在浓度为600 μmol/L时,生物量降低42.6%。Zn在彩色豆马勃中以活性较低的草酸盐、难溶于水的磷酸盐、果胶酸盐以及与蛋白质呈结合态或吸着态的形式为主。Zn胁迫显著提高了彩色豆马勃菌丝中CAT、POD和SOD活性,增加了GSH和黑色素含量,但对AsA的含量没有显著影响。本研究表明,彩色豆马勃主要通过调节Zn的分布及抗氧化系统,增加黑色素含量,增强对Zn的耐受性,为外生菌根真菌修复重金属污染土壤提供了理论支持。 相似文献
93.
目的:探讨女性盆底功能障碍性疾病的相关因素及盆底超声测定压力性尿失禁SUI的临床意义。方法:选取我院2019年-2020年共收治的63例盆底功能障碍性疾病患者作为研究对象,将其分为研究组,另取同期来我院进行体检的63例健康女性作为对照组,对所有女性应用盆底超声检测,对比两组女性静息状态下和Valsalva状态下的盆底超声检查指标,对通过问卷调查方式,调查两组女性的一般临床治疗,对于女性盆底功能障碍性疾病的相关因素进行单因素分析与多因素分析,最终得出盆底肌功能障碍性疾病的相关因素。结果:在静息状态下通过盆底超声发现,研究组与对照组膀胱尿道后角、肛提肌裂孔面积、尿道倾斜度对比差异显著(P<0.05),两组女性膀胱颈位置、膀胱位置对比无明显差异(P>0.05);在Valsalva状态下通过盆底超声发现,研究组与对照组膀胱尿道后角、肛提肌裂孔面积、尿道倾斜度、膀胱颈位置、膀胱位置对比差异显著(P<0.05);两组女性年龄、BMI、孕次、产次、绝经情况以及白带清洁度是否≥Ⅲ度情况对比差异显著(P<0.05),两组女性子宫肌瘤史情况对比无显著差异(P>0.05);logistic回归分析结果显示,年龄、绝经情况、子宫肌瘤史和白带清洁度≥Ⅲ度不是盆底功能障碍性疾病的独立危险因素(P>0.05),BMI、孕次、产次为盆底功能障碍性疾病的独立危险因素(P<0.05)。结论:盆底肌超声在对盆底功能障碍性疾病患者压力性尿失禁的诊断中具有重要价值,在静息状态下和Valsalva状态下发现患者的膀胱经移动情况与尿道倾斜情况。年龄、BMI、孕次、产次、绝经情况以及白带清洁度是否≥Ⅲ度可能与盆底功能障碍性疾病具有一定关系,BMI、孕次、产次为盆底功能障碍性疾病的独立危险因素。 相似文献
94.
摘要 目的:探讨电针阴部神经刺激疗法联合Kegel盆底康复训练对产后压力性尿失禁(SUI)患者盆底肌力、尿流动力学和生活质量的影响。方法:选取2019年6月~2021年11月期间于我院就诊的产后SUI患者109例,按照入院就诊奇偶顺序分为两组,其中对照组54例,接受Kegel盆底康复训练,研究组55例,接受电针阴部神经刺激疗法联合Kegel盆底康复训练。对比两组疗效、漏尿量、尿失禁程度、盆底肌力、尿流动力学和生活质量。结果:研究组的临床总有效率高于对照组(P<0.05)。两组治疗后盆底肌肌力各指标(手测肌力和Ⅰ类肌纤维最大值、Ⅱ类肌纤维平均值)均升高,且研究组高于对照组(P<0.05)。两组治疗后漏尿量、尿失禁程度评分均下降,且研究组低于对照组(P<0.05)。两组治疗后尿流动力学相关指标[腹压漏尿点压(AL-PP)、最大尿流率(Qmax)和最大尿道闭合压力(MUCP)]均升高,且研究组高于对照组(P<0.05)。两组治疗后尿失禁生活质量量表(I-QOL)各维度(限制性行为、心理影响、社交活动受限)评分及总分均升高,且研究组高于对照组(P<0.05)。结论:电针阴部神经刺激疗法联合Kegel盆底康复训练可有效改善产后SUI患者的盆底肌肌力和尿失禁情况,减少漏尿量,同时可促进尿流动力学恢复,进而提高患者的生活质量。 相似文献
95.
The efficient seeding of juvenile mussels is critical to the sustainability and profitability of mussel aquaculture. However, seeding mussels is highly inefficient, with many juveniles being lost in the following few months. One possible cause of these losses could be the development of biofouling assemblages. Therefore, the relationships between biofouling accumulation and losses of juveniles were assessed. Losses of juvenile mussels were initially high (42.9–49.1% over approximately one to two weeks), with lower rates of loss over the following four to five months. Biofouling development followed a successional pattern beginning with colonisation by amphipods, subsequent establishment of macroalgae, and the formation of an assemblage dominated by mussels and sessile invertebrates. However, biofouling development did not play a major role in the loss of juveniles. Rather, large-scale losses of mussels occurred shortly after seeding when biofouling was scant, suggesting alternative causes of loss were in operation. 相似文献
96.
Jing Wu Fei Guan Wei Luo Zhi-Wei Yuan Rong-Qiong Chen Xin Gou Xin Shi Hai-Xiang Guo Ke-Wei Fang 《Journal of cellular physiology》2019,234(10):17800-17811
Urinary incontinence (UI) is known as a distressing condition particularly among older adults, and negatively associated with health-related quality of life in both males and females. Prelamin A accumulation has been found in all progeroid laminopathies and is obviously linked to cell and organism aging. Therefore, this study was expected to investigate the effect of prelamin A on detrusor on UI. Prelamin A expression in clinical and animal samples was detected. To investigate the degree of prelamin A accumulation and detrusor calcification/aging, the detrusor cells were subcultured separately into low and high passage. The low-passage subculture cells were treated with transfection of overexpressed prelamin A plasmid, and transfection of overexpressed prelamin A plasmid and application of farnesyl transferase inhibitor (FTIs) H-9279, respectively. Zmpste24, Icmt and lamin A/C expression were detected to explore how prelamin A affected detrusor calcification/aging. Prelamin A was overexpressed in aged detrusor cells, indicating prelamin A expression was positively related to the age of subjects. The degree of prelamin A accumulation and detrusor calcification/aging was higher in aged rats and high passage subculture cells. Zmpste24, Icmt and lamin A/C were poorly expressed in cells transfected with overexpressed prelamin A, as well as cell proliferation activity decreased and calcium deposition and apoptotic rate increased. Furthermore, we also found that the effect of overexpressed prelamin A was lost when cells were treated with H-9279. These findings provide evidence that prelamin A overexpression impairs degradation of its farnesylated form, thus causing prelamin A accumulation which induces detrusor calcification/aging in UI. 相似文献
97.
Anamika Sharma Ramandeep K. Sandhi Shabeg S. Briar John H. Miller Gadi V. P. Reddy 《Journal of Applied Entomology》2019,143(4):460-469
Wireworms, the larvae of click beetles (Elateridae), are difficult to manage due to their habitats and behaviour. Wireworms pose a major threat to the wheat crop in the north‐western USA. Seed treatment with neonicotinoids, biological control management and some cultural controls are recommended to manage these pests. Trap cropping is an emerging way to manage wireworms. In strawberry and potato crops, trap cropping has been found effective at attracting wireworms away from the principal crop. An earlier study in the Golden Triangle area of Montana found that pea and lentil could be effective trap crops for managing wireworms in spring wheat. In the present study, experiments were conducted at two locations. The effectiveness of peas and lentils as trap crops with wheat at different seeding densities was assessed [pea at 0, 4, 8, 16 seeds/sq.ft. or 0, 43, 86, 172 seeds/sq.m.; lentil at 0, 6, 12, 18 OR 0, 65, 130, 194 seeds/sq.m.; both with wheat at 0, 11, 22, or 28 seeds/sq.ft. or 0, 120, 230, 300 seeds/sq.m.] in a randomized design where all three crops were intercropped. Both trap crops were found to be effective in protecting wheat at standard seeding rates of 8 seeds/sq.ft. for pea and 12 seeds/sq.ft. for lentils. At these seeding rates, higher numbers of wireworms were found to be attracted to the trap crop, resulting in higher yield (7%–10%) of the associated spring wheat plant stands at 22 seeds/sq.ft. To develop an effective trap crop strategy, the pea–wheat and lentil–wheat spatial patterns that are possible need to be assessed in further field trials. Proper design and evaluation of the cost–benefit ratio of pea and lentil as trap crops are likely to produce good results for wheat crops in Montana. 相似文献
98.
Forecasting Environmental Responses to Restoration of Rivers Used as Log Floatways: An Interdisciplinary Challenge 总被引:1,自引:0,他引:1
Christer Nilsson Fabio Lepori Björn Malmqvist Erik Törnlund Niclas Hjerdt James M. Helfield Daniel Palm Johan Östergren Roland Jansson Eva Brännäs Hans Lundqvist 《Ecosystems》2005,8(7):779-800
Log floating in the 19th to mid 20th centuries has profoundly changed the environmental conditions in many northern river
systems of the world. Regulation of flow by dams, straightening and narrowing of channels by various piers and wing dams,
and homogenization of bed structure are some of the major impacts. As a result, the conditions for many riverine organisms
have been altered. Removing physical constructions and returning boulders to the channels can potentially restore conditions
for these organisms. Here we describe the history of log driving, review its impact on physical and biological conditions
and processes, and predict the responses to restoration. Reviewing the literature on comparable restoration efforts and building
upon this knowledge, using boreal Swedish rivers as an example, we address the last point. We hypothesize that restoration
measures will make rivers wider and more sinuous, and provide rougher bottoms, thus improving land-water interactions and
increasing the retention capacity of water, sediment, organic matter and nutrients. The geomorphic and hydraulic/hydrologic
alterations are supposed to favor production, diversity, migration and reproduction of riparian and aquatic organisms. The
response rates are likely to vary according to the types of processes and organisms. Some habitat components, such as beds
of very large boulders and bedrock outcrops, and availability of sediment and large woody debris are believed to be extremely
difficult to restore. Monitoring and evaluation at several scales are needed to test our predictions. 相似文献
99.
目的:探讨针刺按摩水道穴法治疗产后尿潴留的方法。方法:对我科自1993年3月-2001年3月的67例产后尿潴留患者进行观察记录,并将67例患者随机分为两组,采用两种方法治疗。一组是针刺按摩水道穴法;另一组是足三里穴位注射新斯的明法,对两种方法的疗效进行对照研究,观察治疗效果及治疗后王排尿所需时间。结果:用针刺按摩水道穴法治疗35例,显效率62.8%,有效率3.4.3%,无效率2.9%。对照组足三里穴位注射新斯的明法,治疗32例,显效率28.1%,有效率50%,无效率21.9%。另外,用针刺按摩水道穴法治疗,起效快,治疗后15分钟内显效率61.8%,30分钟内显效率29.4%,而用新斯的明穴位注射法治疗,15分钟内显效率为0,30分钟内显效率为64%。结论:针刺按摩法治疗产后尿潴留,操作简单,起效快,疗效显著,无任何副作用。 相似文献
100.