植物蛋白激酶研究进展

近年来,在分子生物学技术不断完善和在酵母与动物蛋白激酶研究的基础上,植物蛋白激酶的研究已取得了很大的进展。就近十年来国内外学者对植物蛋白激酶的发现,家族分类,磷酸化过程及其生理功能等方面的研究进行综述。最后分析了存在的问题并对今后的研究提出了展望。     

鼠尾胶原蛋白提取、分离、纯化方法的建立及鉴定

目的建立一种高效提取、分离、纯化鼠尾胶原蛋白的方法。方法通过对鼠尾进行剥离获得鼠尾腱,用Tris-HCl缓冲液、胃蛋白酶处理获得鼠尾胶原蛋白原液、反复使用氯化钠溶液进行分级盐析、醋酸溶液复溶进行鼠尾胶原蛋白的纯化。超纯水透析除去无机盐类获得纯化的鼠尾胶原蛋白。通过SDS-PAGE蛋白质电泳、氨基酸含量分析等技术手段鉴定。结果本研究建立的方法可以获得高纯度的鼠尾胶原蛋白,纯度达到电泳纯。与国外进口的商业化鼠尾胶原蛋白产品相比无差异。研究了提取、分离、纯化参数对得率、纯度的影响,建立了最优的鼠尾胶原蛋白提取条件,胃蛋白酶用量：1∶500,酶解时间：72 h,盐析浓度：2 mol/L,提取所用酸溶液：0.05mol/L醋酸溶液。结论为鼠尾胶原蛋白的扩大化生产提供了合适的工艺参数,为大量获得鼠尾胶原蛋白并进行更深层次的功效方面研究提供了理论支持和实践基础。     

枣果实病害侵染与发病时期的研究

从河北沧州的不同枣树品种上,定期采集枣树组织分离,调查枣果病害病菌的侵入时期.结果表明,病原菌在枣树枝条萌芽期就开始侵染,金丝小枣的主要病原菌的侵染顺序为:链格孢(Alternaria alternata)最先侵染,细极链格孢(Alternaria tenuissima)其次,梭壳孢菌(Fusicoccum sp.)和橄榄色盾壳霉(Coniothyrium olivaceum)最后侵染:冬枣的主要病原菌的侵染顺序为:梭壳孢菌(Fusicoccum sp.)最先侵染,细极链格孢(Alternariatenuissima)其次,链格孢(Alternariaalternata)最后侵染;梨枣的主要病原菌的侵染顺序为:细极链格孢(Alternariatenuissima)最先侵染,链格孢(Alternariaalternata)其次,橄榄色盾壳霉(Coniothyrium olivaceum)最后侵染.金丝小枣、冬枣、梨枣的果实发病高峰期均为9月下旬.     

铅胁迫对黄瓜幼苗抗氧化酶活性及同工酶的影响

采用水培法和聚丙烯酰胺凝胶电泳法,研究铅胁迫对黄瓜幼苗过氧化物酶(POD)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性及同工酶的影响.结果表明,铅胁迫下黄瓜幼苗地上部POD活性除第5天外均随铅浓度的增加而逐渐降低,POD同工酶谱带和表达量减少.在0～500 mg·L^-1铅浓度范围内,SOD活性随铅浓度的增加而增加,第7天达到最大值后急剧下降,低于同期对照值,900 mg·L^-1铅处理SOD活性随时间的延长逐步降低,SOD酶谱带和表达量与铅浓度呈负相关.CAT酶谱带无明显变化,而表达量存在差异.     

Effects of Elevated CO2 and High Temperature on Single Leaf and Canopy Photosynthesis of Rice

The increase of atmospheric CO2 concentration is indisputable. In such condition, photosynthetic response of leaf is relatively well studied, while the comparison of that between single leaf and whole canopy is less emphasized. The stimulation of elevated CO2 on canopy photosynthesis may be different from that on single leaf level. In this study, leaf and canopy photosynthesis of rice ( Oryza sativa L. ) were studied throughout the growing season. High CO2 and temperature had a synergetic stimulation on single leaf photosynthetic rate until grain filling. Photosynthesis of leaf was stimulated by high CO2, although the stimulation was decreased by higher temperature at grain filling stage. On the other hand, the simulation of elevated CO2 on canopy photosynthesis leveled off with time. Stimulation at canopy level disappeared by grain filling stage in beth temperature treatments. Green leaf area index was not significantly affected by CO2 at maturity, but greater in plants grown at higher temperature. Leaf nitrogen content decreased with the increase of CO2 concentration although it was not statistically significant at maturity. Canopy respiration rate increased at flowering stage indicating higher carbon loss. Shading effect caused by leaf development reached maximum at flowering stage. The CO2 stimulation on photosynthesis was greater in single leaf than in canopy. Since enhanced CO2 significantly increased biomass of rice stems and panicles, increase in canopy respiration caused diminishment of CO2 stimulation in canopy net photosynthesis, keaf nitrogen in the canopy level decreased with CO2 concentration and may eventually hasten CO2 stimulation on canopy photosynthesis. Early senescence of canopy leaves in high CO2 is also a possible cause.     

特发性腹膜后纤维化一例并文献复习

目的:分析腹膜后纤维化(RPF)的诊断以及治疗情况,以提高对RPF的认识。方法:回顾性分析我科18F-FDGPET/CT诊断的1例RPF患者的临床资料,并对相关文献进行复习。结果:本例患者以腹胀及右下腹部隐痛不适就诊,腹部CT表现为腹主动脉周围肿块,18F-FDGPET/CT显示腹膜后间隙中线大血管周围糖代谢增高肿块,经CT引导下穿刺及手术病理确诊为特发性腹膜后纤维化。结论:腹膜后纤维化属罕见病,CT、MRI在诊断中有较重要作用,PET/CT在IRPF的诊断及治疗随访中有比较重要的价值,在治疗方面,糖皮质激素治疗效果较好,晚期常需要手术治疗。     

植物磷胁迫蛋白和铁胁迫蛋白研究进展

综述了近十年来国内外有关研究植物磷胁迫蛋白和铁胁迫蛋白的文献,着重阐述了磷胁迫和铁胁迫条件下的植物蛋白质变化,如新的蛋白和新的多肽的特异产生,以及相关的分子生物学进展。     

哲罗鱼消化系统器官发生发育的组织学观察

采用形态观察与连续组织切片技术,对哲罗鱼(Hucho taimen)胚胎期(水温7~8℃)和胚后期(水温3~14℃)消化系统的发生发育进行观察和研究。结果表明,哲罗鱼受精11d形成原始的消化管。受精18d肝原基出现,U型胃雏型形成。受精30d鱼体破膜,口能自由闭合。破膜8d后,齿形成,肛门与外界相通,消化道初步形成口咽腔、食道、U型胃、肠和肛门。破膜16d,胰及瓣囊出现,仔鱼消化系统初步具备了摄食和消化外源性食物的能力。破膜24d后,鱼体开始上浮,主动摄食,由内源性营养转向混合性营养。破膜30d后,卵黄囊完全被吸收,各消化器官功能和结构逐步发育完善,鱼体由混合性营养进入外源性营养阶段。此后随着鱼体的生长消化器官逐步发育成熟,舌齿和下颌齿分别为双排,胃腺发达,形成网状结构,幽门盲囊较多,肠为直行,肝和胰为相互分开的独立器官。     

Cytochemical Localization of Reserves during Seed Development in Arabidopsis thaliana under Spaceflight Conditions

Successful development of seeds under spaceflight conditionshas been an elusive goal of numerous long-duration experimentswith plants on orbital spacecraft. Because carbohydrate metabolismundergoes changes when plants are grown in microgravity, developingseed storage reserves might be detrimentally affected duringspaceflight. Seed development in Arabidopsis thaliana plantsthat flowered during 11 d in space on shuttle mission STS-68has been investigated in this study. Plants were grown to therosette stage (13 d) on a nutrient agar medium on the groundand loaded into the Plant Growth Unit flight hardware 18 h priorto lift-off. Plants were retrieved 3 h after landing and siliqueswere immediately removed from plants. Young seeds were fixedand processed for microscopic observation. Seeds in both theground control and flight plants are similar in their morphologyand size. The oldest seeds from these plants contain completelydeveloped embryos and seed coats. These embryos developed radicle,hypocotyl, meristematic apical tissue, and differentiated cotyledons.Protoderm, procambium, and primary ground tissue had differentiated.Reserves such as starch and protein were deposited in the embryosduring tissue differentiation. The aleurone layer contains alarge quantity of storage protein and starch grains. A seedcoat developed from integuments of the ovule with gradual changein cell composition and cell material deposition. Carbohydrateswere deposited in outer integument cells especially in the outsidecell walls. Starch grains decreased in number per cell in theintegument during seed coat development. All these characteristicsduring seed development represent normal features in the groundcontrol plants and show that the spaceflight environment doesnot prevent normal development of seeds in Arabidopsis. Arabidopsis ; spaceflight; embryo; endosperm; seed coat; storage reserves     

shRNA靶向干扰COX-2抑制人肝癌裸鼠皮下移植瘤及其血管生成

目的:探讨重组干扰质粒pshRNA-COX-2对人肝癌细胞Hep3B裸鼠皮下移植瘤生长和肿瘤血管生成的抑制作用。方法:重组干扰质粒pshRNA-COX-2转染Hep3B细胞并筛选后,RT-PCR和Western blot检测COX-2mRNA和蛋白表达,RT-PCR检测VEGFmRNA表达。将被成功转染的Hep3B细胞种植于裸鼠皮下,测量肿瘤大小,4周后处死裸鼠,免疫组织化学法检测肿瘤组织中COX-2蛋白表达和肿瘤微血管密度(MVD)。结果:与未转染细胞相比,干扰组COX-2mRNA和蛋白表达抑制率分别为65.3%和52.8%(P<0.05),干扰组VEGFmRNA表达抑制率为56.5%(P<0.05)。干扰组瘤体大小明显小于阴性组和空白组(P<0.01)。干扰组COX-2得分和MVD均明显低于阴性组和空白组(P<0.01)。结论:pshRNA-COX-2通过抑制COX-2表达明显抑制人肝癌细胞Hep3B裸鼠皮下移植瘤生长和肿瘤血管生成。