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71.
72.
王鑫  周宁新  段伟宏 《生物磁学》2014,(8):1576-1579
原发性肝癌严重威胁着人类的健康,全球每年新增的病例数约为50万,其中54%发生在我国,且患者在3年内复发率高于60%,可见诊治形势十分严峻。肝癌的临床分期系统对于患者的预后评估以及选择何种治疗方案有着极其重要的意义。国内外虽有此类研究的相关内容,但将各种分期的评价及适用范围、发展趋势相结合进行分析的较少。本文对国际上多种常用的分期方案(TNM分期、Child-Pu曲分期、Okuda分期、CLIP评分、JIS分期、CUPI指标、CIS记分)进行探讨,论述各种方案间的差异及相互关系,并对未来可能发展方向进行展望。经本文分析多项研究发现:TNM分期更适用于外科病人,Child—Pugh对肝功能受损的患者具有较好的预后价值,而Okuda、CLIP、JIs分期适用于不适合手术治疗的进展期病人,CUPI指数则对慢性乙肝患者有疗效,CIS适用于非手术治疗的患者。随着肿瘤分子生物学技术的进步,肝癌分期有可能上升到分子病理学的水平,肝癌切除的根治程度将划分得更为细致,以反映患者肝癌切除后所处状态的多种可能性,分子指标也将更加客观、敏感,有利于患者早期的诊断与治疗。  相似文献   
73.
目的:对高脂饮食诱发的大鼠NASH模型与蛋氨酸胆碱缺乏饮食诱发的小鼠NASH模型进行血清学及病理学比较,并初步探讨两种模型的发病过程及机制。方法:高脂饮食喂养SD大鼠8周,蛋氨酸胆碱缺乏饮食喂养C57BL/6小鼠2周,以制备NASH模型。取材后,血清用比色法对TG、CHO、FPG的含量进行检测,用放免法对FINS的含量进行检测,并对HOMA-IR指数进行计算;肝组织制成石蜡切片及冰冻切片进行HE及油红O染色,并根据"NAFLD活动度积分"对各组肝组织进行NASH分级评估。结果:高脂饮食大鼠血清中TG、CHO、FPG、FINS的含量显著升高,经计算HOMA-IR指数显著升高;MCD小鼠血清中TG、CHO的含量显著下降,FPG、FINS的含量未发生显著性改变,经计算HOMA-IR指数未发生显著性改变。HE染色、油红O染色及NAFLD活动度积分结果显示,高脂饮食大鼠及MCD小鼠的肝组织均已发展到NASH阶段。结论:两种造模方法均可稳定的模拟人类NASH疾病的血清学及病理学变化,其中高脂饮食诱发的大鼠NASH模型可模拟人类的发病过程及机制,能够复制胰岛素抵抗、氧化应激等人类全身代谢紊乱表现,在NASH研究领域更占优势。  相似文献   
74.
Analysis of natural host-parasite relationships reveals the evolutionary forces that shape the delicate and unique specificity characteristic of such interactions. The accessory long gland-reservoir complex of the wasp Leptopilina heterotoma (Figitidae) produces venom with virus-like particles. Upon delivery, venom components delay host larval development and completely block host immune responses. The host range of this Drosophila endoparasitoid notably includes the highly-studied model organism, Drosophila melanogaster. Categorization of 827 unigenes, using similarity as an indicator of putative homology, reveals that approximately 25% are novel or classified as hypothetical proteins. Most of the remaining unigenes are related to processes involved in signaling, cell cycle, and cell physiology including detoxification, protein biogenesis, and hormone production. Analysis of L. heterotoma's predicted venom gland proteins demonstrates conservation among endo- and ectoparasitoids within the Apocrita (e.g., this wasp and the jewel wasp Nasonia vitripennis) and stinging aculeates (e.g., the honey bee and ants). Enzyme and KEGG pathway profiling predicts that kinases, esterases, and hydrolases may contribute to venom activity in this unique wasp. To our knowledge, this investigation is among the first functional genomic studies for a natural parasitic wasp of Drosophila. Our findings will help explain how L. heterotoma shuts down its hosts' immunity and shed light on the molecular basis of a natural arms race between these insects.  相似文献   
75.
摘要 目的:对比弹性髓内钉与接骨板内固定治疗儿童股骨干骨折的临床疗效。方法:本研究为回顾性研究,选取我院于2018年3月~2019年8月期间收治的儿童股骨干骨折患者98例,根据固定方式的不同将患儿分为A组(n=50,接骨板内固定治疗)和B组(n=48,弹性髓内钉治疗),观察两组优良率、术前/术后相关指标及并发症发生情况。结果:B组的优良率高于A组(P<0.05)。B组手术时间、切口长度短于A组,术中出血量少于A组(P<0.05)。B组骨折愈合时间、住院时间、手术至内固定拆除时间、取出内固定手术时间短于A组(P<0.05)。两组患儿并发症发生率对比,差异无统计学意义(P>0.05)。结论:相对于接骨板内固定治疗,弹性髓内钉治疗儿童股骨干骨折,疗效更好,可有效改善术中、术后指标,且不增加并发症的发生率。  相似文献   
76.
芋种质资源开花结实状况调查   总被引:1,自引:1,他引:0  
对保存在国家种质武汉水生蔬菜资源圃中的芋属(Colocasia)种质资源的开花结实状况调查表明:(1)在自然条件下,所有滇南芋[Colocasia antiquorum (L.) Schott](2n=2x)中的野芋[即原C. esculenta (L.) var. antiquorum]和花用芋(即原C. tonoimo Nakai)资源全部开花;芋[Colocasia esculenta (L.) Schott]开花状况表现为:魁芋(2n=2x)、多头芋(2n=3x)、魁子兼用芋(2n=3x)都不开花,国内多子芋中,紫柄多子芋(2n=3x)都不开花,乌绿柄多子芋(2n=3x)和绿柄多子芋(2n=3x)有部分品种开花,但开花的品种具有不确定性;来源于东南亚国家的多子芋中,绿柄多子芋(2n=3x)开花率高,花期长,另有1份紫柄多子芋(2n=3x)开花,与国内多子芋(2n=3x)差异较大。开花率表现为东南亚多子芋(2n=3x)等于或高于国内芋;国内芋中,二倍体大于三倍体。花期最长的是东南亚的绿柄多子芋(2n=3x),国内芋中,二倍体的开花率大于三倍体,二倍体的花期长于三倍体。(2)乌绿柄多子芋和花用芋的芽色都为红色,属于短附属器,其余类型的芽色为白色,属于长附属器。(3)在自然条件下,仅有2份紫柄野芋种质结实,其它种质未见结实。(4)本文还对不同类型芋的始花期、末花期、花期、单株花序丛数、单个叶轴花序数、单株总花序数、佛焰苞管部长度、佛焰苞檐部长度、附属器长、雄花序长、中性花序长、雌花序长等进行了比较。  相似文献   
77.
Pediococcus damnosus (P. damnosus) bacteriophage (phage) clP1 is a novel virulent phage isolated from a municipal sewage sample collected in Southern Ireland. This phage infects the beer spoilage strain P. damnosus P82 which was isolated from German breweries. Sequencing of the phage has revealed a linear double stranded DNA genome of 38,013 base pairs (bp) with an overall GC content of 47.6%. Fifty seven open reading frames (ORFs) were identified of which 30 showed homology to previously sequenced proteins, and as a consequence 20 of these were assigned predicted functions. The majority of genes displayed homology with genes from the Lactobacillus plantarum phage phiJL-1. All genes were located on the same coding strand and in the same orientation. Morphological characterisation placed phage clP1 as a member of the Siphoviridae family with an isometric head (59 nm diameter) and non-contractile tail (length 175 nm; diameter 10nm. Interestingly, the phage clP1 genome was found to share very limited identity with other phage genome sequences in the database, and was hence considered unique. This was highlighted by the genome organisation which differed slightly to the consensus pattern of genomic organisation usually found in Siphoviridae phages. With the genetic machinery present for a lytic lifecycle and the absence of potential endotoxin factors, this phage may have applications in the biocontrol of beer spoilage bacteria. To our knowledge, this study represents the first reported P. damnosus phage genome sequence.  相似文献   
78.
Development of bioprocesses with mammalian cell culture deals with different bioreactor types and scales. The bioreactors might be intended for generation of cell inoculum and production, research, process development, validation, or transfer purposes. During these activities, not only the difficulty of up and downscaling might lead to failure of consistency in cell growth, but also the use of different bioreactor geometries and operation conditions. In such cases, criteria for bioreactor design and process transfer should be carefully evaluated in order to select appropriate cultivation parameters. In this work, power input, mixing time, impeller tip speed, and Reynolds number have been compared systematically for the cultivation of the human cell line AGE1.HN within three partner laboratories using five different bioreactor systems. Proper operation ranges for the bioreactors were identified using the maximal cell‐specific growth rate (μmax) as indicator. Common optimum values for process transfer criteria were found in these geometrically different bioreactors, in which deviations of μmax between cultivation systems can be importantly reduced. The data obtained in this work are used for process standardization and comparability of results obtained in different bioreactor systems, i.e. to guarantee lab‐to‐lab consistency for systems biology approaches using mammalian cells.  相似文献   
79.
ObjectiveClinical symptoms of diabetic nephropathy patients and non-diabetic nephropathy are compared and analyzed, hemodialysis effect and quality of life of two kinds of nephrotic patients are analyzed.MethodsRespectively extract 1300 cases of diabetic nephropathy and non-diabetic nephropathy patients admitted to different hospitals during December 2011-December 2014. Based on whether the patient suffers from diabetes, they were divided into diabetic group and control group. Hemodialysis of two groups of patients were followed up to observe effectiveness of blood treatment, and complications were observed after one year of follow-up.ResultsHematodialysis effectiveness of diabetic nephropathy patients is significantly lower than that of non-diabetic nephropathy group. After 1 year’s follow-up, it can be found that survival rate of diabetic nephropathy patients is much lower than that of control group. In statistical comparison of data involved in the two groups of patients, P < 0.05, the difference is statistically significant.ConclusionTreatment effect of diabetic nephropathy patients is relatively poor compared to that of non-diabetic patients. In clinics, management and prevention of diabetic patients should be strengthened to avoid complication of nephropathy which brings serious injury to patients.  相似文献   
80.
An approximate and practical solution is proposed for the Behrens-Fisher problem. This solution is compared to the solutions considered by Mehta and Srinivasan (1970) and Welch's (1937) approximate t-test in terms of the stability of the size and magnitude of the power. It is shown that the stability of the size of the new test is better than that of Welch's t when at least one of the sample sizes is small. When the sample sizes are moderately large or large the sizes and powers of all the recommended tests are almost the same.  相似文献   
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