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NEBNext Ultra II RNA NEBNext Ultra II RNA Library Prep Directional and Non-directional NEBNext Ultra II RNA Library Prep non-directional Increasing Library Yields

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Library yield is one important measure of library preparation success, and the revision of each step in the RNA library prep workflow enables substantially higher yields with the NEBNext Ultra II RNA Library Prep Kit compared to earlier NEBNext kits, as well as another commercially available kit. Achieving sufficient yields from low input amounts can be especially challenging. However, the high efficiencies of the NEBNext Ultra II workflow overcomes these challenges, and users can now obtain higher library yields with lower input amounts for RNA prepared by poly(A) mRNA enrichment or rRNA depletion workflows. Further, samples of low quality, such as FFPE RNA, can also be used successfully, especially in conjunction with the NEBNext rRNA Depletion Kit (Human/Mouse/Rat).

Generate the highest yields, from a wide range of input amounts

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NEBNext Ultra II RNA Library Prep Kit for Illumina
Includes optimized mixes for non-directional RNA library preparation (fragmentation, cDNA synthesis, end repair/dA-tailing, adaptor ligation and PCR enrichment steps) for sequencing on the Illumina platform.


NEBNext Ultra II RNA Library Prep with Sample Purification Beads
Includes optimized mixes for non-directional RNA library preparation (fragmentation, cDNA synthesis, end repair/dA-tailing, adaptor ligation and PCR enrichment steps) plus SPRIselect beads for size selection and cleanup.


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从20世纪80年代开始, 血管紧张素转换酶抑制剂(ACEI)被推荐为治疗慢性心衰的基础药物。1995年已将ACEI定为治疗慢性心衰的首选药物。但是, 在我国目前临床使用的ACEI剂量明显低于心衰治疗指南及临床试验所推荐的有效剂量。据调查通常治疗慢性心衰的依那普利(enalapril)平均剂量为9mg/天, 卡托普利(captopril)为37.5mg/天, 而临床试验推荐的依那普利剂量为40mg/天, 卡托普利剂量为150mg/天。据调查仅22%的慢性心衰患者接受了上述临床试验推荐剂量。目前认为20%的心衰患者治疗无效是因为ACEI剂量不足所致。近年来许多学者研究了不同剂量ACEI在治疗慢性心衰中的作用, 本文简介 ACEI不同剂量与慢性心衰血流动力学、临床症状、预后以及不良反应之间的关系。 
 
1     不同剂量ACEI的血流动力学作用 

    ACEI用于慢性心衰可以产生有益的血流动力学作用。Barry等研究证明赖诺普利(lisinopril)的急性血流动力学作用具有剂量依赖性, 应用10mg组较2.5mg、5mg组明显降低肺动脉楔压(PCWP)、肺动脉压(PAP)和体循环阻力(SVR), 明显增高心指数(CI)。Nussberger等对55例慢性心衰患者在应用喹那普利84天后进行右心导管测量, 发现长期喹那普利治疗仅肺动脉楔压、肺动脉收缩压的下降,在10mg, 5mg组较2.5mg组明显。从上述研究可知, ACEI的急性血流动力学效应与剂量有关而慢性血流动力学效应与剂量关系不明显。 

2     不同剂量ACEI对临床症状的影响 

    Rocca等的研究通过自身对照显示服依那普利患者在口服10mg/天时运动耐力显著低于口服40mg/天时。Pacher等的研究显示卡托普利大于75mg/天时, 82%的慢性心衰患者临床症状明显改善, 5%出现恶化, 而小于75mg/天时, 仅34%症状改善, 33%恶化, NYHA分级仅在大于75mg/天时有明显改善。喹那普利研究组在一项多中心双盲随机安慰对照试验中对225例慢性心衰患者进行研究, 发现喹那普利40mg, 20mg ,10mg/天与安慰剂相比, 分别延长运动时间55%, 51%, 41%,运动耐力改善与剂量具有明显关系。 

3     不同剂量ACEI对慢性心衰预后的影响 
  
    Aileen的一项评价不同剂量依那普利对再住院率影响的回顾性研究中, 314例患者随访3年, 发现在小于5mg/天组, 90天再住院率无降低, 在大于10mg/天组, 降低28%。Denis证实卡托普利100mg/天比50mg/天更明显降低心衰恶化率、再住院率和心血管事件发生率。Pacher等观察了不同剂量赖诺普利对临床长期预后的影响, 大剂量为30~40mg/天, 小剂量为2.5~5mg/天, 3164例慢性心衰患者进入研究, 随访3~4年的结果显示, 大剂量组平均住院日18.5天, 小剂量组22.5天。大剂量心衰住院率明显降低。联合评价死亡率和住院率,大剂量组较小剂量组显著降低。大剂量组延迟各种原因的死亡和住院7.1月。 

4     不同剂量ACEI的不良反应和耐受性 

    ACEI的主要不良反应有低血压、血肌酐可逆性增高、高钾血症和干咳、眩晕等。Denis的研究显示卡托普利大剂量组的眩晕和低血压发生率略高, 但两组间血肌酐(Cr)水平无差别。Davidson等则观察到赖诺普利大剂量组较小剂量组血肌酐清除率明显降低。在ATLAS试验中大剂量ACEI血肌酐增加程度比小剂量组高, 但两组内血肌酐增加大于10mg/L者无差别。眩晕、低血压在大剂量组发生率较高, 但通过减少或停用利尿病或加用其他辅助治疗后均可得到控制, 因不良反应退出研究者两组间无差别。大剂量组咳嗽和心衰恶化的发生率反而较小剂量组低, Pacher认为这与改善肺淤血和心衰症状有关。Massie在3793例慢性心衰患者的多中心随机双盲试验中评价了大剂量赖诺普利的耐受性。发现退出研究发生率,大剂量组(32.5~35mg/天)为27.1%,小剂量组(2.5~5mg/天)为30.7%。不良反应发生率在大剂量组为79%, 小剂量组为83.3%。在收缩压<120mmHg、血肌酐>132.6μmol/L、年龄>70岁及糖尿病等高危人群中, 也能良好耐受大剂量的赖诺普利, 仅严重不良反应的发生率相对增加。由此可见, 不良反应发生率在大剂量组虽然较高,但并未发生难以控制的严重不良反应, 患者大多可良好耐受高剂量ACEI。 

5    应走出慢性心衰治疗的误区 

    大量临床试验有力地证明了大剂量比目前临床普遍使用的小剂量效果更好, 患者大多能良好耐受。我国“慢性收缩性心力衰竭治疗建议”中指出“治疗慢性心衰应尽量将ACEI剂量逐渐增加到目标剂量或最大耐受剂量。维持治疗也要用目标剂量或最大耐受剂量,应终生使用。”正确使用ACEI治疗慢性心衰,推广、应用我国慢性心衰治疗建议的原则,让我国广大心衰患者得到最佳治疗,任重而道远。 

However, the high efficiencies of the NEBNext Ultra II workflow ...and users can now obtain higher library yields with lower input amounts...adaptor ligation and ...