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1.
目的:回顾分析Peutz-Jegher综合征(PJS)的诊治经验,提高其手术治疗水平。方法:收集广东医学院附属医院、第二附属医院10a PJS的临床资料,分析诊疗情况。结果:10a两院收治PJS9例均有皮肤粘膜色素沉着和胃肠道多发性息肉,其中保守治疗1例,纤维内镜电切2例,外科手术5例,改良武术中内镜(从胃肠壁切口进镜)配合手术治疗1例,疗效满意。结论:PJS息肉症状轻,小于2cm可内科治疗;于胃、十二指肠及结肠的可内镜电切;多段肠道(特别是空、回肠)的多发性息肉宜行改良武术中纤镜配合手术切除,应避免胃肠部分切除。  相似文献   
2.
中国传统医学是世界文化遗产,我们中华儿女,有义务传承、弘扬中兽医学,先祖留下的魁宝不能丢,为此,我们中兽医专业研究生和本科生带着这种使命感,参与到实施国家科技基础性工作专项--西南区传统中兽医抢救与整理(项目编号:2013FY110600)工作,对西南区中兽医专家教授和基层老中兽医进行了采访,其中,2014年3月28日,采访了西南大学荣昌校区动物医学系主任、中兽医药专家刘娟教授。  相似文献   
3.
海洋渔业转型系统的构建是一个复杂的工程,主要由原因子系统、动力子系统、支持子系统和目标子系统四部分构成,各子系统之间相互作用,相互制约,维护着系统的稳定性。当然,要保证整个系统的顺利运行还需要一系列的保障条件,主要包括物质资本、人力资本、风险、技术、环境、社会服务及政府政策等各方面的保障因素,各个方面都影响着转型的每一个环节和每一个过程。  相似文献   
4.
This experiment aimed to study the effects of supplemental methionine sources, 2-hydroxy-4 methyl(thio)butanoic acid(HMTBa) and DL-Methionine(DL-Met), on productive performance, egg quality, and redox status of laying ducks. A total of 792 healthy 25-wk-old Longyan laying ducks with similar body weights were randomly allotted to 11 treatment groups. Each treatment group had 6 replicates of 12 ducks. The trial lasted for 16 wk. Ducks were fed a basal deficient diet(Met: 0.24%; Met + Cys: 0.51%) o...  相似文献   
5.
田间抗性监测发现了大麦云纹斑病菌新型的抗性菌株,这类菌株对苯并咪唑类(多菌灵)、Phenylcarbamate(乙霉威)及三唑类(三唑醇)表现多重抗性,先前发现的多菌灵抗药性菌株均是在β-维管蛋白基因的198位点出现等位基因的突变,而新发现的菌株则仅在200位点(TTC)由苯并氨酸转变成赖氨酸(TAC)而导致对3种药剂的抗性。温室试验证明,这类菌株的致病性和野生敏感菌的致病性几乎一致,说明大麦云纹斑病菌对杀菌剂抗药性的发展与致病性之间没有相关性。  相似文献   
6.
Cells crawl by coupling protrusion of their leading edge with retraction of their cell body. Protrusion is generated by the polymerization and bundling of filaments, but the mechanism of retraction is less clear. We have reconstituted retraction in vitro by adding Yersinia tyrosine phosphatase to the major sperm protein-based motility apparatus assembled from Ascaris sperm extracts. Retraction in vitro parallels that observed in vivo and is generated primarily by disassembly and rearrangement of the cytoskeleton. Therefore, cytoskeletal dynamics alone, unassisted by conventional motors, are able to generate both of these central components of amoeboid locomotion.  相似文献   
7.
As an emergent electronic material and model system for condensed-matter physics, graphene and its electrical transport properties have become a subject of intense focus. By performing low-temperature transport spectroscopy on single-layer and bilayer graphene, we observe ballistic propagation and quantum interference of multiply reflected waves of charges from normal electrodes and multiple Andreev reflections from superconducting electrodes, thereby realizing quantum billiards in which scattering only occurs at the boundaries. In contrast to the conductivity of conventional two-dimensional materials, graphene's conductivity at the Dirac point is geometry-dependent because of conduction via evanescent modes, approaching the theoretical value 4e(2)/pih (where e is the electron charge and h is Planck's constant) only for short and wide devices. These distinctive transport properties have important implications for understanding chaotic quantum systems and implementing nanoelectronic devices, such as ballistic transistors.  相似文献   
8.
以宁夏葡萄产业中大量种植的3个葡萄品种为试材建立再生体系.采用花药、茎尖进行愈伤组织诱导,比较了3种葡萄用花药、茎尖培养诱导愈伤组织形成、分化、生根的必须培养条件,获得不定芽分化再生植株.结果表明:葡萄花药愈伤组织形成胚性愈伤组织的能力很低,几乎不能分化成苗;而茎尖愈伤组织形成胚性愈伤组织的能力很高,分化成苗率极高,达100%.B5培养基诱导宁夏葡萄茎尖愈伤组织和分化丛生效果最好;KT有利于愈伤组织分化;茎尖浓度以0.8~1.0 cm最好.  相似文献   
9.
The study of gene function in vivo is considered one of the top achievements of modern biology, inasmuch as it provides tools to study gene function in the context of the whole animal. In chickens, techniques of DNA-mediated gene transfer are less advanced than in other animal or livestock models, and remain a significant challenge. The study presented here is the first to show that a hydrodynamics-based gene-transfer technique, originally developed for naked DNA transfer in mice, can be applied to chickens. Rapid injection of naked plasmids containing expression cassettes into the jugular vein of 6- to 10-day-old chicks resulted in specific expression of the transgenes. A CMV promoter-driven luciferase reporter gene was expressed at significant levels in the liver during the first 3 days post-injection with lower levels also detected in the kidney. Significantly, all injected birds showed detectable levels of luciferase expression. Similarly, injection of a plasmid containing the secreted human coagulation factor IX (hFIX) gene under the control of human alpha-1-anti-trypsin promoter resulted in detectable levels of the hFIX in the plasma during the first 2 days post-injection. The method described herein has the potential for a quick and simple route for gain and loss-of function experiments in chicken liver and kidney, as well as for studying systemic effects of secreted proteins and hormones.  相似文献   
10.
The challenges of reusing mining and mineral-processing wastes   总被引:2,自引:0,他引:2  
Mining and mineral-processing wastes are one of the world's largest chronic waste concerns. Their reuse should be included in future sustainable development plans, but the potential impacts on a number of environmental processes are highly variable and must be thoroughly assessed. The chemical composition and geotechnical properties of the source rock determine which uses are most appropriate and whether reuse is economically feasible. If properly evaluated, mining waste can be reused to reextract minerals, provide additional fuel for power plants, supply construction materials, and repair surface and subsurface land structures altered by mining activities themselves.  相似文献   
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