The distribution of topically applied heavy metals in the soil

Summary Long-term pot experiments were conducted to determine the leaching potential of topically applied lead, cadmium, and nickel through the soil. Four rates of each metal (0, 10, 100 and 200 mg/kg soil), in the nitrate form were used. Metals were extracted with acidic ammonium acetate after 30 weeks of intermittent leaching. The concentration of extractable element varied with the depth in the soil and the type of extractable metal. Lead was confined to the upper few centimeters of soil whereas cadmium moved down to a considerable depth. Nickel was more uniformly distributed over the total soil depth than the other two metals. The concentration gradients observed are discussed with respect to their effect on germination and yield of plants.     

Effects of Field Application of Tebuconazole on Yield, Yield Components and the Mycotoxin Content of Fusarium-infected Wheat Grain

Winter wheat cultivar Basalt was artificially inoculated with Fusarium culmorum at the end of anthesis and treated with the systemic fungicide tebuconazole (Folicur^®) a few days before and/or after inoculation. Check plots remained uninoculated and unsprayed. Head infections, yield, yield components and the percentage of Fusarium‐ infected kernels were determined. Artificial Fusarium inoculation lowered yield significantly by 24.2‐45.0%. Any fungicide treatment saved yield, thousand grain weight and kernel numbers per head. Pre‐infectional application of tebuconazole was superior to application carried out post‐infection. Moreover, the fungicide controlled deoxynivalenol (DON) synthesis in the field to a considerable extent, and enabled good control of Fusarium head blight, glume blotch and the percentage of Fusarium‐infected kernels. The levels of Fusarium kernel infection after harvest clearly reflected the DON content of w heat grain.     

猪诱导性多能干细胞技术的研究进展及应用前景

猪作为实验材料,具有由于来源方便、基因序列与人类的相近及其在畜牧业中的重要地位等优势,成为国内外研究的热点,但是猪的胚胎干细胞(Embryonic stem cells,ESC)建系方面的研究进展缓慢。诱导性多能干细胞(induced pluripotent stem cells,iPSC)技术的诞生,开创了体细胞重编程的全新方法。猪iPSC体系的建立将为家畜ESC体系的建立奠定基础,同时也对提高猪转基因克隆的效率,高效育种和保种,乃至生物医学领域均产生深远的影响。文章综述了iPSC技术的主要进展,重点阐述了猪iPSC技术的现状及其在生物医学和畜牧业中的应用前景,以期为从事该领域研究的科研人员提供参考。     

瑞芬太尼、芬太尼及瑞芬太尼- 芬太尼联合应用对肥胖患者麻醉 后苏醒质量的研究

目的:探讨芬太尼和瑞芬太尼分别应用于肥胖患者全身麻醉中苏醒质量的优缺点,对比研究两药联合应用对于提高肥胖患者苏醒质量的可行性和有效性。方法:60例体重指数>30的肥胖患者随机分为三组,分别应用芬太尼(F组)、瑞芬太尼(R组)和瑞芬太尼联合应用芬太尼(RF组)进行全身麻醉,麻醉时间2小时左右,从停止用药开始分别观察BIS值恢复时间,睁眼时间,5mi/kg潮气量恢复时间,每分通气量恢复时间,拔管时血压,定向力恢复时间,进行视觉模拟评分和镇静/警觉评分和拔管后动脉血气的测量。结果:RF组和R组的BIS值恢复时间和睁眼时间及每分通气量恢复时间无差异,均优于F组。而且RF组和R组中BIS值恢复时间和睁眼时间相关性良好,F组中两指标无相关性。停药后三组患者分别进行1小时、2小时4、4小时和24小时的VAS评分和OAA/S评分,VAS评分中R组在四个时相于其他两组比较均有统计学意义(P<0.05),均较两组高,F组和RF组在手术后1、2小时时相上比较无统计学意义(P>0.05)。OAA/S评分中,F组在1、2及4小时三个时相均低于其他组,R组和RF组在四个时相比较均无统计学意义(P>0.05)。定向力恢复时间三组比较,R组和RF组之间无统计学意义(P>0.05),F组均与其他两组有差别,且长于其他两组(P<0.05)。血气分析结果中RF组优于其他组(P<0.05)。全麻后的副反应中RF组的发生率较低。结论:瑞芬太尼联合应用芬太尼对于肥胖患者全身麻醉意识恢复快,通气恢复时间短,镇痛效果好,血流动力学平稳,苏醒质量高。     

Mechanisms and role of microRNA deregulation in cancer onset and progression

MicroRNAs are key regulators of various fundamental biological processes and, although representing only a small portion of the genome, they regulate a much larger population of target genes. Mature microRNAs (miRNAs) are single-stranded RNA molecules of 20-23 nucleotide (nt) length that control gene expression in many cellular processes. These molecules typically reduce the stability of mRNAs, including those of genes that mediate processes in tumorigenesis, such as inflammation, cell cycle regulation, stress response, differentiation, apoptosis and invasion. MicroRNA targeting is mostly achieved through specific base-pairing interactions between the 5' end ('seed' region) of the miRNA and sites within coding and untranslated regions (UTRs) of mRNAs; target sites in the 3' UTR diminish mRNA stability. Since miRNAs frequently target hundreds of mRNAs, miRNA regulatory pathways are complex. Calin and Croce were the first to demonstrate a connection between microRNAs and increased risk of developing cancer, and meanwhile the role of microRNAs in carcinogenesis has definitively been evidenced. It needs to be considered that the complex mechanism of gene regulation by microRNAs is profoundly influenced by variation in gene sequence (polymorphisms) of the target sites. Thus, individual variability could cause patients to present differential risks regarding several diseases. Aiming to provide a critical overview of miRNA dysregulation in cancer, this article reviews the growing number of studies that have shown the importance of these small molecules and how these microRNAs can affect or be affected by genetic and epigenetic mechanisms.     

XXIst century magnetotherapy

Abstract

This paper discusses the state of the art therapeutic application of magnetic and electromagnetic fields (EMF) in treatment of various medical problems – from pain relief to musculoskeletal trauma, to vascular and endocrine disorders. The paper describes problems related to physical parameters of used fields, biophysical dosimetry, clinical protocols, and safety of the device operators. Clinical benefits and mechanisms of action are also discussed.     

探讨CT技术在肺结节疾病诊断中的应用

目的：探讨CT技术在肺结节疾病诊断中的应用。利用CT技术提供的影像学特征,及时准确的诊断肺结节疾病,从而更具体更全面的提高对该疾病的认识,减少误诊的发生。方法：回顾性分析我院2010年-2012年确诊的符合相应临床诊治标准的肺结节患者48例的临床资料,通过CT扫描分析其具体的特征表现。结果：在所选的48例中,纵隔淋巴结增大45例,双侧肺门淋巴结增大44例,胸部淋巴结增大患者48例。肺部病变者33例,其中单发结节患者2例,多发结节患者25例,支气管血管束增粗者14例,磨玻璃样影案例者9例,实变案例5例。胸膜病发患者13例。结论：我们通过分析发现,胸部有典型影像学表现形式的肺结节病例诊断较容易,无典型影像学表现的患者诊断较为困难。因此我们认为利用CT技术诊断肺结节疾病具有特异性意义,值得临床医生重视。     

两种实验技术在蛋白质-蛋白质相互作用检测中的应用

蛋白质是生命活动的主要承担者。蛋白质种类繁多,结构多样,具有十分广泛的生物学功能,可作为载体蛋白、酶蛋白和信号肽等参与调控细胞内的各种代谢活动。生物体内蛋白质与其他分子的相互作用,尤其是蛋白质-蛋白质之间的相互作用,是蛋白质行使这些重要生物学功能的基础。通过研究可以相互作用的蛋白质形成的各种复合体,对揭示蛋白质的功能,更清楚地阐明细胞生长、发育、分化和凋亡的生命活动规律,为重大疾病的预防、治疗和新药开发提供了理论基础。目前科研工作者在基于分子生物学、生物化学、微生物学和生物物理学的基础上已经发展出了许多蛋白质相互作用的研究技术,本文着重对现有研究方法中的生物膜干涉技术和微量热泳动技术进行介绍和综述。     

微生物角蛋白酶的特性及其应用研究进展

角蛋白作为家禽加工和农业废弃物的主要成分,因其结构中富含能抵抗普通蛋白酶和化学催化剂降解的稳定交联二硫键而难以被利用,因此每年都在环境中大量积累,造成了严重的环境污染。微生物角蛋白酶可将角蛋白废弃物转化为可再次利用的产物,带来了经济的可行性及环境的可持续发展。本文主要综述了角蛋白酶的生物化学特性、角蛋白酶的基本结构及其表达特性,总结了其应用价值及角蛋白降解机制,最后展望了微生物角蛋白酶的进一步研究方向。