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排序方式: 共有256条查询结果,搜索用时 140 毫秒
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目的:探讨分析柱状经腹会阴直肠癌切除术术后并发症发生的可能原因,并提出解决对策。方法:回顾分析我院自2010年1月至2014年5月采用柱状经腹会阴直肠癌切除术的68例直肠癌患者的临床资料。记录并分析患者发生术后并发症的情况,探讨发生的可能原因及可行对策。结果:68例患者术后出现并发症共9例,占13.2%。切口并发症4例,术后排尿困难2例,术后骶尾部疼痛3例。结论:柱状经腹会阴直肠癌切除术因为手术切除范围大,术后并发症亦随之凸显。但通过精细的术中解剖、重叠缝合腹膜关闭盆底、骶前通畅引流、合理掌握尿管拔管时机等手段,可有效降低术后并发症的发生。  相似文献   
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Homologous recombination requires nucleolytic degradation (resection) of DNA double‐strand break (DSB) ends. In Saccharomyces cerevisiae, the MRX complex and Sae2 are involved in the onset of DSB resection, whereas extensive resection requires Exo1 and the concerted action of Dna2 and Sgs1. Here, we show that the checkpoint protein Rad9 limits the action of Sgs1/Dna2 in DSB resection by inhibiting Sgs1 binding/persistence at the DSB ends. When inhibition by Rad9 is abolished by the Sgs1‐ss mutant variant or by deletion of RAD9, the requirement for Sae2 and functional MRX in DSB resection is reduced. These results provide new insights into how early and long‐range resection is coordinated.  相似文献   
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Nucleotide modifications to microRNAs or their precursors can influence their processing and/or activity. A challenge to their analysis is the lack of independent references for the termini generated by primary processing; typically, these are empirically assigned as the most abundant mapped reads. Mirtrons offer such an independent measure since these microRNA hairpins are defined by splicing. Consequently, mirtron-derived reads that deviate from splice sites reflect modification following primary processing. Analysis in Drosophila revealed multiple modification patterns, including select alterations of 5' termini, many 3' resection events, and unexpectedly abundant 3' untemplated monouridylation. Resections occur on mature AGO1-loaded species, whereas uridylation occurs on pre-miRNAs but is compatible with dicing and AGO1 loading. Strikingly, we found many mirtrons whose modified reads are more abundant than those produced by primary processing. In some cases, these abundant modified reads matched the genome owing to fortuitous uridines in downstream flanking exons, thus highlighting the value of an independent reference for the primary-processed sequence. We could further extend the principle of abundant and preferred uridylation of mirtrons, relative to canonical pre-miRNAs, to Caenorhabditis elegans, mouse, and human. Finally, we found that 3' resection occurs broadly across AGO1-loaded canonical miRNA and star species. Altogether, these findings substantially broaden the complexity of terminal modification pathways acting upon small regulatory RNAs.  相似文献   
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庞建  詹宇  吴建军  胡峰  缪勋忠 《激光生物学报》2012,21(5):479-480,F0003,469
目的:观察分析经尿道前列腺电切(TURP)联合输尿管镜钬激光碎石术治疗前列腺增生症(BPH)合并膀胱结石的效果。方法:本组61例患者先行膀胱结石钬激光碎石,然后采用经尿道前列腺电切术(TURP)治疗前列腺增生症。结果:61例一次性治疗成功,术后结石无残留,排尿情况较前明显改善,IPSS评分均分由24.4分降到9.4分,最大尿流率由7.2 mL/s上升到19.5 mL/s。结论:钬激光碎石及TURP同期治疗前列腺增生合并膀胱结石是安全有效的方法。  相似文献   
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巨大痛风石手术切除一例及文献复习   总被引:1,自引:0,他引:1  
目的:探讨晚期巨大痛风石结节的临床表现及手术治疗效果.方法:回顾性分析一例典型病例患者的临床资料、手术方法的选择以及病理学表现.结果:该患者为晚期通风症患者,发展为痛风石.表现为痛风石结节增生,破坏肌腱以及骨组织.各项辅助检查以及手术后病理结果均支持痛风病的诊断.通过手术切除第一跖趾关节旁巨大痛风石,疗效满意.结论:痛风是一种因嘌呤代谢紊乱所致的疾病,本例患者经过各种保守对症治疗均无效.接收此患者后,通过文献复习分析以及临床检查确诊,本病例痛风病变已发展至晚期巨大痛风石结节.只有通过手术治疗才能彻底治愈.手术后证明对晚期巨大痛风石结节同时伴有骨关节破损的痛风石患者行手术治疗是完全可行,且疗效显著.  相似文献   
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Studies were undertaken to examine the possibility that changes occur in the responsiveness of thermoregulatory neurons in the anterior hypothalamus to endogenously released neurotransmitters upon the development of tolerance to morphine. In experiments conducted at an environmental temperature of 20–21°C, tolerance produced by the subcutaneous implantation of morphine alkaloid pellets failed to alter the temperature response of rats to intraventricular injections of 5-HT (10 μg), NE (20 μg) or pilocarpine (100 μg). It is concluded that tolerance development to morphine-induced hypothermia is not a result of changes in the postsynaptic sensitivity to the putative neurotransmitters in the thermoregulatory center.  相似文献   
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《Molecular cell》2020,77(1):26-38.e7
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