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101.
Eight species of aquatic oligochaetes, belonging to the families Naididae and Tubificidae, are reported, of which six species are new to the Nigiris. Tubifex tubifex known from Coonoor is reported again from this area.  相似文献   
102.
Treatment of the lysosomal enzyme, α-L-iduronidase, with 2,3 butanedione, an arginine modifying reagent, under conditions where enzyme activity was unaffected, reduced by 50% the internalization of the enzyme into cultured human fibroblasts. The lowered rate of internalization was a result of a reduced binding of the enzyme to cell surface receptors. The butanedione treatment of α-L-iduronidase caused a 90% reduction of binding when isolated fibroblast membranes were used as the source of receptor. This marked reduction of binding was also seen when membranes from a rat chondrosarcoma were examined. Although there is ample evidence that the receptor recognizes mannose 6-phosphate residues on the enzyme, the results suggest that other structural features, such as arginine moieties, may also be important in iduronidase binding.  相似文献   
103.
The hybrid bacterial foraging algorithm based on many-objective optimizer   总被引:1,自引:0,他引:1  
A new multi-objective optimized bacterial foraging algorithm - Hybrid Multi-Objective Optimized Bacterial Foraging Algorithm (HMOBFA) is presented in this article. The proposed algorithm combines the crossover-archives strategy and the life-cycle optimization strategy, look for the best method through research area. The crossover-archive strategy with an external archive and internal archive is assigned to different selection principles to focus on diversity and convergence separately. Additionally, according to the local landscape to satisfy population diversity and variability as well as avoiding redundant local searches, individuals can switch their states periodically throughout the colony lifecycle with the life-cycle optimization strategy. all of which may perform significantly well. The performance of the algorithm was examined with several standard criterion functions and compared with other classical multi-objective majorization methods. The examiner results show that the HMOBFA algorithm can achieve a significant enhancement in performance compare with other method and handles many-objective issues with solid complexity, convergence as well as diversity. The HMOBFA algorithm has been proven to be an excellent alternative to past methods for solving the improvement of many-objective problems.  相似文献   
104.
生物医药产业是中国医药制造业的第三大产业,也是粤港澳大湾区重点扶持的新兴高技术产业之一。透视产业主营业务收入与各类指标的关联情况是进一步指导粤港澳大湾区生物医药产业建设规划的必要之举。而灰色综合关联分析法是探索指标间关联程度的重要工具。通过多种权威途径获得粤港澳大湾区生物医药产业规模以上企业数量、企业孵化器数量、新增专利数、自然科学基金立项投入总额、非自然科学基金立项数量、产学研合作项数量六大指标数据。采用灰色关联分析法,将所得数据进行建模并求解,得出这六大指标与粤港澳大湾区生物医药产业主营业务收入的关联度。结果显示,规模以上企业数量与粤港澳大湾区生物医药产业主营业务收入的关联度最高,其次为自然科学基金立项投入总额,再次为产学研合作项数量,非自然科学基金立项数量位列第四,企业孵化器数量、新增专利数分别位列第五、第六。因此,谋求粤港澳大湾区生物医药产业的进一步发展应着重从提高规模以上企业数量、重视自然科学基金投入、加强政产学研合作3个层面入手。  相似文献   
105.
竹类植物是美国采集者在我国采集和引种的一类主要植物。在众多的竹类植物采集者中, 莫古礼(Floyd Alonzo McClure)是最具代表性的一位, 他于1919-1940年在岭南大学开展竹类植物研究, 在此期间多次采集竹类植物标本并引种竹类植物到美国。本研究通过大量文献研究、档案查阅以及实地调研, 整理了莫古礼采集竹类植物的路线和采集地, 并对竹类植物学名进行校对, 分析了莫古礼在华研究、采集和引种竹类植物的历史及其影响。经统计, 莫古礼在华期间竹类植物标本采集地涉及12个省级行政区39个地级市, 主要集中在广东、海南、香港等地; 引种地涉及9个省级行政区的25个地级市; 共采集竹类植物标本727号1,840份, 隶属20属93种(含种下单位, 下同), 分别占我国竹类植物属和种的58.8%和17.4%; 共引种竹类植物255份, 隶属于17属77种, 分别占我国竹类植物属和种的50.0%和14.4%。莫古礼在华采集和引种竹类植物极大地发展了竹类植物分类学, 所采集的竹类植物标本为后人竹类植物研究提供了极大的帮助, 所引种的竹类植物极大丰富了美国竹类植物种类, 也促进了竹类植物在美国的应用。  相似文献   
106.
中医体质学以人为研究对象,为了研究不同体质构成特点、演变规律、影响因素、分类标准,从而指导疾病的预防、诊治、康复与养生。目前关于生理和病理状态下的中医体质研究日益受到关注,因为对其研究符合中医”治未病”的理念,而关于少数民族的中医体质类型研究开展较少,但对少数民族之间和汉族之间中医体质的比较研究及与生活习惯,生活环境的联系将能更好地说明先天因素和后天环境对中医体质形成的影响。本文就这一领域的研究现状进行总结,对少数民族中医体质的研究一方面可为少数民族人群的疾病防治提供依据,另一方面有助于中医体质形成机理的阐明。  相似文献   
107.
ftsZ基因是控制细胞分裂的关键基因,其蛋白能够在分裂位点形成一个环状结构而影响细胞分裂.为了研究木薯质体分裂与木薯淀粉品质形成的关系,根据木薯基因组数据库上的预测序列,设计引物,从木薯基因组中分离了与质体分裂相关的ftsZ家族3个新基因(ftsZ1,ftsZ2,ftsZ3).分别将它们与荧光蛋白基因(GFP)融合,构建了3个原核表达载体pET-fisZ1-GFP、pET-fisZ2-GFP、pET-fisZ3-GFP,并转化大肠杆菌BL21(DE3).通过荧光显微镜观察菌体的表型和分裂,初步鉴定了木薯质体分裂相关基因ftsZ家族对细胞分裂的作用.结果显示:尽管木薯与大肠杆菌的亲缘关系较远,ftsZ基因的同源性较低,但是两者表现出相似的功能,木薯ftsZ基因的表达能严重影响大肠杆菌细胞分裂.这一结果为进一步研究木薯ftsZ家族基因的功能奠定了基础.  相似文献   
108.
Head and neck squamous cell carcinoma (HNSCC) remains a major health problem worldwide. We aimed to identify a robust microRNA (miRNA)-based signature for predicting HNSCC prognosis. The miRNA expression profiles of HNSCC were obtained from The Cancer Genome Atlas (TCGA) database. The TCGA HNSCC cohort was randomly divided into the discovery and validation cohort. A miRNA-based prognostic signature was built up based on TGCA discovery cohort, and then further validated. The downstream targets of prognostic miRNAs were subjected to functional enrichment analyses. The role of miR-1229-3p, a prognosis-related miRNA, in tumorigenesis of HNSCC was further evaluated. A total of 305 significantly differentially expressed miRNAs were found between HNSCC samples and normal tissues. A six-miRNA prognostic signature was constructed, which exhibited a strong association with overall survival (OS) in the TCGA discovery cohort. In addition, these findings were successfully confirmed in TCGA validation cohort and our own independent cohort. The miRNA-based signature was demonstrated as an independent prognostic indicator for HNSCC. A risk signature-based nomogram model was constructed and showed good performance for predicting the OS for HNSCC. The functional analyses revealed that the downstream targets of these prognostic miRNAs were closely linked to cancer progression. Mechanistically, in vitro analysis revealed that miR-1229-3p played a tumor promoting role in HNSCC. In conclusion, our study has developed a robust miRNA-based signature for predicting the prognosis of HNSCC with high accuracy, which will contribute to improve the therapeutic outcome.  相似文献   
109.
110.
《Anthrozo?s》2013,26(4):351-361
ABSTRACT

This paper reports the attitudes and actions of 614 Bahamian pet caregivers towards their pets, irrespective of the type of pet kept. The results are discussed in the context of an American study by Pamela Carlisle-Frank and Joshua Frank, published in 2006, which posed similar questions. While Bahamians appeared to interact less with their pets than Americans (e.g., 56.9% of Bahamians took pets on walks compared with 71.5% of Americans), they had some important attitudes towards animals in common with Americans, such as disapproving of declawing of cats (67.9% of Bahamians and 71.1% of Americans) and long-term chaining of dogs (83.0% of Bahamians and 84.9% of Americans), and the recognition of the need to help animals (85.0% of Bahamians and 90.5% of Americans). Some Bahamian respondents voluntarily suggested that white people and black people cared for animals differently. The results suggest that the differences between the two communities, in terms of actions and attitudes towards pets, may explain why some American visitors to The Bahamas think that Bahamians do not care for their pets. These differences are of potentially great economic importance, as most tourists visiting The Bahamas come from the US.  相似文献   
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