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51.
Summary Chromosome samples were prepared on a plastic coverslip covered with a polyester membrane and were subjected to the C-banding treatment. The C-band pattern was obtained after Giemsa staining. The C-band positive regions of the Crepis chromosomes were identified, dissected out by irradiation with a micro-laser beam and recovered in Eppendorf tubes.  相似文献   
52.
目的:探讨不同手术方式对分化型甲状腺癌患者临床治疗的效果及其预后的影响。方法:回顾性分析了2005.02-2012.07入住我院的60例分化型甲状腺癌患者的临床资料,采用如下三种不同的治疗方式:甲状腺切除术联合双侧中央区颈淋巴结清扫手术;保留对侧喉返神经入喉处甲状腺组织的甲状腺次全切除术联合单侧改良颈淋巴结清扫手术;保留对侧喉返神经入喉之处甲状腺组织的甲状腺次全切除手术联合双侧改良颈淋巴结清扫手术。结果:(1)上述三组患者术后,患者的甲状旁腺的功能低下之间均存在显著的统计学差异(P〈0.01),三组喉返神经损伤的发生率之间也存在显著的统计学差异(P〈0.01);本组60例患者均获10-172个月(平均为93.5±10.2)的随访,上述三种手术方式下患者的癌症复发率分别为77.8%、4.5%及45.0%,三组具有显著的统计学差异(P〈0.01);生化治愈率分别为27.8%、95.5%及50.0%;平均生存时间分别为(92.3±12.5)个月、(105.8±14.5)个月及(112.3±20.9)个月。(2)三组患者术后生存质量总得分分别为(122±9)、(118±8)及(125±9)分。结论:与甲状腺切除术联合双侧中央区颈淋巴结清扫手术进行对比,保留对侧喉返神经入喉处甲状腺组织的甲状腺次全切除术联合单侧改良颈淋巴结清扫手术与保留对侧喉返神经入喉之处甲状腺组织的甲状腺次全切除手术联合双侧改良颈淋巴结清扫手术在生存时期、术后生存质量两个方面不具显著性差异。  相似文献   
53.
An aortic dissection (AD) is a serious condition defined by the splitting of the arterial wall, thus generating a secondary lumen [the false lumen (FL)]. Its management, treatment and follow-up are clinical challenges due to the progressive aortic dilatation and potentially severe complications during follow-up. It is well known that the direction and rate of dilatation of the artery wall depend on haemodynamic parameters such as the local velocity profiles, intra-luminal pressures and resultant wall stresses. These factors act on the FL and true lumen, triggering remodelling and clinical worsening. In this study, we aimed to validate a computational fluid dynamic (CFD) tool for the haemodynamic characterisation of chronic (type B) ADs. We validated the numerical results, for several dissection geometries, with experimental data obtained from a previous in vitro study performed on idealised dissected physical models. We found a good correlation between CFD simulations and experimental measurements as long as the tear size was large enough so that the effect of the wall compliance was negligible.  相似文献   
54.
摘要 目的:探讨内镜黏膜下剥离术(ESD)治疗胃间质瘤的临床疗效及术后出血的危险因素。方法:选取2018年2月至2020年3月我院诊治的135例胃间质瘤患者作为研究对象,统计其ESD治疗后的各项临床指标,比较治疗前后患者的细胞免疫功能和胃肠激素变化,根据患者ESD治疗后是否发生出血将其进一步分为术后出血组12例和术后未出血组123例,分析胃间质瘤患者ESD术后出血的危险因素。结果:135例患者平均手术时间为(45.89±8.79)min,平均术后进食时间为(3.05±0.98)d,平均住院时间为(6.11±0.95)d,完整切除率为96.30%,术后出血发生率为8.89%,术后穿孔发生率为5.19%,术后感染发生率为9.63%。经单因素分析发现,ESD治疗胃间质瘤术后出血与高血压、糖尿病、血小板(PLT)、血清降钙素原(PCT)和C反应蛋白(CRP)有关(P<0.05)。与治疗前相比,患者治疗后CD3+、CD4+、CD4+/CD8+、血清胃动素(MTL)、胃泌素(GAS)和生长激素释放肽(Ghrelin)水平明显下降,而CD8+明显升高(P<0.05)。进一步多因素Logistic回归分析表明,胃间质瘤患者ESD术后出血的危险因素包括高血压、糖尿病、PCT>2.73 ng/mL以及CRP>62.19 ng/mL(P<0.05),而保护因素则为PLT>151.38×109/L(P<0.05)。结论:ESD治疗胃间质瘤患者的疗效确切,安全性较好,但其会引起胃间质瘤患者的细胞免疫功能和胃肠激素分泌下降。同时,高血压、糖尿病、PCT>2.73 ng/mL和CRP>62.19 ng/mL是胃间质瘤患者ESD术后出血的危险因素。  相似文献   
55.
Dengue viruses are classified into four serotypes. Here, we report a 1.7 Å crystal structure of a recombinant dengue‐3 envelope protein domain III (ED3), which contains most of the putative epitopes. Although the fold was well conserved, we found that a local backbone deformation in the first β‐strand, which contains the putative epitope‐1, occurred upon domain isolation. Furthermore, a comparison with dengue‐2 ED3 indicated a large structural change by as much as 4.0 Å at Asp662, located in epitope‐2. These minute structural and surface properties changes observed in the high resolution ED3 structure represent potential determinants for serospecificity and epitope recognition by antibodies. © 2012 Wiley Periodicals, Inc.  相似文献   
56.
Although much progress has been made in the diagnosis and treatment of thoracic aortic dissection (TAD), the overall morbidity and mortality rates of TAD are still high. Therefore, the molecular pathogenesis and etiology of TAD need to be elucidated. In this study, we found that histone deacetylase 1 (HDAC1) expression is dramatically higher in the aortic wall of patients with TAD (than that in a normal group) and negatively correlates with the levels of the vascular smooth muscle cell (SMC) contractile-phenotype markers. Knockdown of HDAC1 upregulated both smooth muscle 22 α (SM22α) and α-smooth muscle actin (α-SMA) in platelet-derived growth factor (PDGF)-BB-treated and -untreated SMCs. In addition, the knockdown of HDAC1 markedly decreased SMC viability and migration in contrast to the control group under the conditions of quiescence and PDGF-BB treatment. We also showed that the expression of polycystic kidney disease 1 (PKD1) is decreased in the aortic wall of patients with TAD and negatively correlates with HDAC1 expression. Overexpressed PKD1 obviously increased SM22α and α-SMA expression and reduced the viability and migration of SMCs, but these effects were attenuated by HDAC1. Furthermore, we demonstrated that HDAC1 serves as an important modulator of the migration and phenotypic switch of SMCs by suppressing the PKD1– mammalian target of the rapamycin signaling pathway. HDAC1 downregulation inhibited media degeneration and attenuated the loss of elastic–fiber integrity in a mouse model of TAD. Our results suggest that HDAC1 might be a new target for the treatment of a macrovascular disease such as TAD.  相似文献   
57.
58.
洗胃法与剖胃法在四种蛙食性分析中的对比   总被引:1,自引:0,他引:1  
在动物的食性研究中,剖胃法因要杀死动物,会产生一系列的生态学影响和伦理学问题,在国际上招致了越来越多的反对,而在我国仍广泛使用。尽管洗胃法已用于食性研究,它的效果却从来没有研究过。我们应用洗胃法研究了浙江宁波郭巨镇四种蛙(黑斑蛙、泽蛙、金线蛙和中华蟾蜍)的食性,并与剖胃法所获得的食性结果进行比较。结果显示:尽管洗胃法在四种蛙胃内食物量的总洗出率(在94.50%以上)和食物个体数的洗出率上(均大于93.46%)略低于剖胃法,但胃内未洗出的与洗出的平均食物个体大小间无差异(所有P>0.3061),两种方法获得的四种蛙的平均食物量和食物个体数也无差异(对食物量所有P>0.8680,对食物个体数所有P>0.7923)。结果表明,洗胃法是比较精确的,在动物的食性研究中,应广泛地推广洗胃法,摒弃剖胃法  相似文献   
59.
目的:研究急性Stanford A型主动脉夹层(AAAD)患者的临床特征,并分析影响其术后院内死亡的危险因素。方法:选取2015年6月~2018年4月河北医科大学第四医院心脏血管外科收治的279例AAAD患者为研究对象,收集患者的基本信息、临床资料,分析AAAD患者的临床特征。所有患者均行手术治疗,按照术后院内的死亡情况将患者分为死亡组和存活组,收集两组患者手术相关信息,采用多因素logistic回归分析对患者术后死亡的危险因素进行分析。结果:279例AAAD患者中,男女比例为2.88:1;患者平均年龄为(52.11±8.91)岁;合并高血压者占66.67%,合并冠心病者占11.47%;患者以胸痛或胸背痛为主要症状(占69.89%);并发症中以心包积液(占43.37%)和主动脉瓣反流(占18.64%)的发生率最高;其平均收缩压、白细胞计数、D-二聚体(DDi)水平均高于正常值上限;心、肾功能不全的发生率分别为23.30%和15.77%;院内死亡率为17.92%。单因素分析结果显示,死亡组和存活组AAAD患者在年龄、是否伴有肾功能不全、是否伴有心功能不全、DDi水平、体外循环时间、手术时间、输血量和术后是否开胸止血方面比较,均有统计学差异(P0.05)。多因素logistic回归分析结果显示,年龄65岁、伴有肾功能不全、体外循环时间≥270 min和术后开胸止血是AAAD患者术后死亡的独立危险因素(P0.05)。结论:AAAD患者发病年龄呈年轻化,多数合并有基础疾病,疼痛为其主要症状,且该病患者并发症多、术后死亡率较高。年龄65岁、伴有肾功能不全、体外循环时间≥270min和术后开胸止血均可显著增加AAAD患者术后死亡风险。  相似文献   
60.
Here we demonstrate the dissection of the crayfish abdominal nerve cord. The preparation comprises the last two thoracic ganglia (T4, T5) and the chain of abdominal ganglia (A1 to A6). This chain of ganglia includes the part of the central nervous system (CNS) that drives coordinated locomotion of the pleopods (swimmerets): the swimmeret system. It is known for over five decades that in crayfish each swimmeret is driven by its own independent pattern generating kernel that generates rhythmic alternating activity 1-3. The motor neurons innervating the musculature of each swimmeret comprise two anatomically and functionally distinct populations 4. One is responsible for the retraction (power stroke, PS) of the swimmeret. The other drives the protraction (return stroke, RS) of the swimmeret. Motor neurons of the swimmeret system are able to produce spontaneously a fictive motor pattern, which is identical to the pattern recorded in vivo 1.The aim of this report is to introduce an interesting and convenient model system for studying rhythm generating networks and coordination of independent microcircuits for students’ practical laboratory courses. The protocol provided includes step-by-step instructions for the dissection of the crayfish’s abdominal nerve cord, pinning of the isolated chain of ganglia, desheathing the ganglia and recording the swimmerets fictive motor pattern extracellularly from the isolated nervous system.Additionally, we can monitor the activity of swimmeret neurons recorded intracellularly from dendrites. Here we also describe briefly these techniques and provide some examples. Furthermore, the morphology of swimmeret neurons can be assessed using various staining techniques. Here we provide examples of intracellular (by iontophoresis) dye filled neurons and backfills of pools of swimmeret motor neurons. In our lab we use this preparation to study basic functions of fictive locomotion, the effect of sensory feedback on the activity of the CNS, and coordination between microcircuits on a cellular level.  相似文献   
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