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81.
Termites from the genus Odontotermes are known to contain numerous species complexes that are difficult to tell apart morphologically or with mitochondrial DNA sequences. We developed markers for one such cryptic species complex, that is, Odontotermes srinakarinensis sp. nov. from Maxwell Hill Forest Reserve (Perak, Malaysia), and characterised them using a sample of 41 termite workers from three voucher samples from the same area. We then genotyped 150 termite individuals from 23 voucher samples/colonies of this species complex from several sites in Peninsular Malaysia. We analysed their population by constructing dendograms from the proportion of shared-alleles between individuals and genetic distances between colonies; additionally, we examined the Bayesian clustering pattern of their genotype data. All methods of analysis indicated that there were two distinct clusters within our data set. After the morphologies of specimens from each cluster were reexamined, we were able to separate the two species morphologically and found that a single diagnostic character found on the mandibles of its soldiers could be used to separate the two species quite accurately. The additional species in the clade was identified as Odontotermes denticulatus after it was matched to type specimens at the NHM London and Cambridge Museum of Zoology.  相似文献   
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83.
通讯作者:蛋白体是脑膜炎球菌外膜蛋白形成的疏水性的毫微粒囊泡状结构,可以安全有效的提高脂多糖,蛋白和多肽等多种抗原疫苗的免疫原性。迄今为止,很多研究显示蛋白体黏膜佐剂的优势潜能。作者检索了近年来国内外关于蛋白体作为免疫佐剂的相关文献,并进行分析、归纳。本文综述了蛋白体的结构、作用机理以及国内外作为黏膜佐剂的研究进展。  相似文献   
84.
目的:了解部队男性官兵前列腺炎的发病情况及影响因素调查。方法:采用整群分层,随机抽样,对某高原部队300名男性官兵进行问卷调查,并对官兵的生殖系统、前列腺液等进行相关检查。结果:发现前列腺炎12人,多数为已婚的干部及入伍前有女朋友的战士。约66%官兵了解生殖健康概念及内容,与被调查者的学历、职务、是否来自城市等有关;对性传播疾病的病种及传播途径了解不够的官兵达20%。结论:部队官兵的生殖健康良好,少数有前列腺炎,最好定期进行生殖系统疾病筛查;部队官兵对生殖健康概念及内容了解尚可,但还应加强宣传教育。  相似文献   
85.
目的:研究担载神经生长因子(NGF)的聚乳酸纤维乳液法静电纺丝的制备工艺,从电压、溶液浓度等工艺条件进行探索,通过扫描电镜对纤维的形态结构进行观察,旨在找到最佳纺丝制备条件,并观察该条件下纤维的体外释放行为和细胞活性。方法:将NGF水溶液分散于聚乳酸(PLLA)溶液中,通过W/O乳液法制备静电纺丝纤维。分别从电压8 k V、10 k V、12 k V,浓度梯度90mg/m L、100 mg/m L、110 mg/m L进行静电纺丝纤维的制备,对纤维的形态等进行表征。使用ELISA对NGF体外释放动力学进行检测,用Alamer Blue试剂考察纤维释放液对于PC12悬浮细胞增殖的影响。结果:浓度和电压对电纺纤维制备影响很大。当浓度过大时,易堵塞纺丝喷头且纤维弯曲,过小时纤维粗细差异较大。电压过大或过小时纤维弯曲情况严重,甚至出现缠绕现象。当浓度为100 mg/m L,电压为10 k V时制备的乳液法静电纺丝聚乳酸纤维直径粗细均匀,具有较好形态。在该条件下的制备的纤维NGF体外有效释放13天,释放液可以促进PC12细胞的增殖。结论:担载NGF的聚乳酸纤维乳液法最佳静电纺丝制备条件为:PLLA溶液浓度100 mg/m L、电压10 k V,该条件下制备的担载NGF的聚乳酸纤维体外释放可累计释放13天,其释放液可有效促进PC12细胞的增殖,为进一步研究担载NGF的聚乳酸纤维导管奠定了一定的工艺基础。  相似文献   
86.
全先奎  王传宽 《生态学报》2016,36(11):3381-3390
兴安落叶松(Larix gmelinii)作为北方森林的主要组成树种,具有广阔的分布范围和多样的生长环境,是研究树木对环境变化响应的理想树种。叶碳利用效率(CUE_L)不仅与树木的碳代谢及生长发育密切相关,而且能反映树木对环境变化的响应与适应。将来自不同地区(即环境条件)的6个兴安落叶松种源的种子播种培育在帽儿山森林生态系统研究站内,在其生长30a后采用研究站和种子来源地间干燥度(AI)的差值(ΔAI)来代表环境变化梯度,研究环境变化对CUE_L的影响。结果表明:CUE_L在不同环境变化梯度间存在显著差异(P0.05),且呈现随ΔAI的增大而减小的趋势。CUE_L与叶片氮含量、叶片磷含量、比叶重及叶绿素含量等均呈线性正相关关系,但较大ΔAI梯度下的CUE_L敏感性更高。CUE_L与种子来源地平均年降水量呈显著线性正相关关系(P=0.05),而与种子来源地AI则呈显著线性负相关关系(P0.01);随种子来源地年平均气温、平均年蒸发量的增加而下降,但其相关性不显著。以上结果表明,环境变化使兴安落叶松CUE_L产生了适应性变异,表现出树木对原生长环境的生态适应。  相似文献   
87.
2015年,世界卫生组织对肺癌的分类提出了气道播散(spread through air spaces,STAS)的概念,作为肺腺癌侵袭的新模式。STAS指的是肺癌细胞在肺实质内经气道播散到肿瘤主灶边缘以外。近年来,随着对STAS研究的深入,研究结果表明STAS作为一种侵袭方式与其他侵袭行为和转移有关。STAS与肺癌的预后存在密切联系,并且与复发的风险独立相关。而选择的手术方式不同,STAS阳性患者的预后大不相同。在影像学方面,STAS有着其特殊的影像学特征,这些影像学特征可以作为STAS可能性估计的工具。因此能否通过影像学等方法判断出是否有STAS存在对选择手术方式和改善患者预后有重要指导意义。这篇综述将重点阐述近年来STAS在与不同类型肺癌的联系、影像学、基因突变等方面的研究概况。  相似文献   
88.
Two associated incomplete thyreophoran dorsal vertebrae from the Callovian Marnes de Dives Formation of the Vaches Noires cliffs, on the Normandy coast, are referred to an indeterminate stegosaur that appears to be different from Lexovisaurus, previously reported from the Callovian of western France. These vertebrae are the first evidence of thyreophorans from the Vaches Noires and complement the dinosaur assemblage from this locality, which hitherto consisted of several theropod taxa and an indeterminate sauropod. The dinosaur record from the Vaches Noires is heavily dominated by theropods and this imbalance is difficult to explain. A possible explanation may be that the dinosaur sample from the Vaches Noires is too small to be statistically significant and representative of the original faunal assemblage from which it is derived.  相似文献   
89.
Helophytic plants contribute significantly in phytoremediation of a variety of pollutants due to their physiological or biochemical mechanisms. Phenol, which is reported to have negative/deleterious effects on plant metabolism at concentrations higher than 500 mg/L, remains hard to be removed from the environmental compartments using conventional phytoremediation procedures. The present study aims to investigate the feasibility of using P. australis (a helophytic grass) in combination with three bacterial strains namely Acinetobacter lwofii ACRH76, Bacillus cereus LORH97, and Pseudomonas sp. LCRH90, in a floating treatment wetland (FTW) for the removal of phenol from contaminated water. The strains were screened based on their phenol degrading and plant growth promoting activities. We found that inoculated bacteria were able to colonize in the roots and shoots of P. australis, suggesting their potential role in the successful removal of phenol from the contaminated water. Pseudomonas sp. LCRH90 dominated the bacterial community structure followed by A. lowfii ACRH76 and B. cereus LORH97. The removal rate was significantly high when compared with the individual partners, i.e., plants and bacteria separately. The plant biomass, which was drastically reduced in the presence of phenol, recovered significantly with the inoculation of bacterial consortia. Likewise, highest reduction in chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total organic carbon (TOC) is achieved when both plants and bacteria were employed. The study, therefore, suggests that P. australis in combination with efficient bacteria can be a suitable choice to FTWs for phenol-degradation in water.  相似文献   
90.
Obesity is a multifactorial metabolic disorder characterized by low grade chronic inflammation. Rare and novel mutations in genes which are vital in several key pathways have been reported to alter the energy expenditure which regulates body weight. The TP53 or p53 gene plays a prominent role in regulating various metabolic activities such as glycolysis, lipolysis, and glycogen synthesis. Recent genome-wide association studies reported that tumor suppressor gene p53 variants play a critical role in the predisposition of type 2 diabetes and obesity. Till date, no reports are available from the Arabian population; hence the present study was intended to assess the association between p53 variants with risk of obesity development in the Saudi population. We have selected three p53 polymorphisms, rs1642785 (C > G), and rs9894946 (A > G), and rs1042522 (Pro72Arg; C > G) and assessed their association with obesity risk in the Saudi population. Phenotypic and biochemical parameters were also evaluated to check their association with p53 genotypes and obesity. Genotyping was carried out on 136 obese and 122 normal samples. We observed that there is significantly increased prevalence p52 Pro72Arg (rs1042522) polymorphism in obese persons when compared to controls at GG genotype in overall comparison (OR: 2.169, 95% CI: 1.086-4.334, p = 0.02716). Male obese subjects showed three-fold higher risk at GG genotype (OR: 3.275, 95% CI: 1.230-8.716, p = 0.01560) and two-fold risk at G allele (OR: 1.827, 95% CI: 1.128-2.958, p = 0.01388) of p53 variant Pro72Arg respectively. This variant has also shown significant influence on cholesterol, LDL level, and random insulin levels in obese subjects (p ≤ 0.05). In conclusion, p53 Pro72Arg variant is highly prevalent among obese individuals and may act as a genetic modifier for obesity development among Saudis.  相似文献   
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