A reactive pattern of ischemia-induced nestin protein in the rat brain     

LEI Wan-long  YUAN Qun-fang  DONG Zhi-hong  YAO Zhi-bin 《园艺学报》2002,18(6):639-642

AIM:To explore the expressive profile of nestin protein in the focal ischemic brain and to study the recovery mechanism of brain focal infarct.METHODS:Cellular morphology,time-course and distribution pattern of nestin positive response were immunohistochemically examined in different brain regions of 36 adult male SD rats. RESULTS:Nestin positive response of different brain regions in sham operated rats was present in small- and micro-vasculartures and the third ventricle bottom and ependyma. A large number of nestin positive cells were detected in ischemic brain, and were more remarkable in the cortical areas of parietal lobe and preoptic area as well as ischemic caudoputamen. Stellate nestin positive cells were located in the deep layer of ischemic cortex, but fibrillary cells were located in the shallow layer. Nestin positive cells in the ischemic caudoputamen showed the same changes of morphology as those cells in the deep layer of ischemic cortex. Morphological and number alterations of nestin positive cells were the most remarkable at 1 weeks post-ischemia, which showed more hypertrophy and proliferation in morphology, and a marked increase in number was present in the ischemic cerebral cortex and the ischemic caudoputamen. These alterations of nestin positive cells persisted up to 6 weeks post-ischemia, and then, the nestin positive response in the ischemic brain decreased gradually.CONCLUSION:Focal cerebral ischemia induces nestin re-expression on reactive astrocytes, which may be very important to the self-recovery of cerebral infarct.  相似文献   

酶联免疫吸附法测定畜禽组织中恩诺沙星的残留量     

杨华生 《安徽农业科学》2015,(24):114-115

利用抗原抗体反应的高度特异性和酶的高效催化作用相结合,测定畜禽组织中恩诺沙星的残留量。结果表明,该检测方法简便、快速、灵敏。  相似文献   

Level and Timing of Nitrogen Fertilizer Application to Early and Semi-early Potatoes (Solanum tuberosum L.) Grown with Irrigation on Light Soils in Norway     

Hugh Riley 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):122-134

Trials were performed with early and semi-early potatoes to test the effects of nitrogen (N) fertilizer level (0-160 kg N ha^-1) and timing (all at planting versus half then and half either soon after emergence or 3 weeks later). All seven trials with earlies were irrigated as required, whilst different irrigation regimes (moderate versus intensive) were compared in two trials with semi-earlies. No benefit was derived from splitting the N application. Haulm growth and N uptake increased in all cases almost linearly up to the highest N level, but tuber yield did not respond in the same way. The optimum N level was 80 kg N ha^-1 for a yield of 15 Mg ha^-1, rising to 120 kg N ha^-1 for a yield of 40 Mg ha^-1. Tuber quality was lowered by the use of excess N fertilizer, particularly in the case of earlies. The quantity of mineralised N present in the soil after harvest rose sharply with above optimum fertilizer use, and the amount of N present in crop residues also increased. The likely leaching after early potatoes was estimated to be up to 80 kg N ha^-1. The proportion of fertilizer N which was not accounted for in either tuber yield, crop residues or mineral N in soil was 26% in earlies and 38% in semi-earlies.  相似文献   

土壤总砷测定前处理方法探讨   总被引：2，自引：0，他引：2  

邹强  刘芳  龚世龙  杨剑虹 《土壤通报》2011,(6):1341-1344

采用加标回收方法比较研究了5种土壤总砷测定的前处理方法(分别为浓HNO3-浓H2SO4-HC1O4法、王水法、浓HNO3-浓H2SO4-V2O5法、浓HNO3-浓H2SO4-V2O5Ⅰ法和浓HNO3-浓H2SO4-V2O5Ⅱ法),结果表明,5种前处理方法的加标回收率在89.9%～102%之间,变异系数在0.56%～5.27%之间。其中,浓HNO3-浓H2SO4-V2O5Ⅰ法处理,土壤所用消解时间40min左右,其回收率较高,在98.5%～99.1%之间,变异系数较小,在0.56%～0.85%之间;该前处理方法具有消解时间最短、加标回收率和精密度高及重现性最好的特点,优于其他4种前处理方法,可作为推荐方法应用。  相似文献   

Cd2+胁迫对紫花苜蓿叶绿素和可溶性糖含量的影响   总被引：2，自引：3，他引：2  

丁晓辉  任丽萍  张春荣  王金利  侯建宇 《华北农学报》2007,22(Z1):64-66

以紫花苜蓿为试材,采用盆栽试验,研究不同浓度Cd2 胁迫对不同茬期紫花苜蓿的叶绿素、可溶性糖的影响。结果表明:随重金属Cd2 胁迫剂量的加大,3茬紫花苜蓿叶绿素含量、可溶性糖含量呈倒"N"形规律变化,即降-升-降的变化,这与重金属诱导下紫花苜蓿的防御机制有关。3茬紫花苜蓿的可溶性糖含量不同,依次是第1茬>第2茬>第3茬,3茬紫花苜蓿的叶绿素含量不同:低浓度Cd2 下,第2茬>第1茬>第3茬;高浓度Cd2 下,第2茬>第3茬>第1茬。主要原因可能是由于苜蓿的收割,导致Cd流失,胁迫作用减弱或者是多种影响因素综合作用的结果。  相似文献   

苗期土壤水分亏缺后玉米光合生理的恢复   总被引：1，自引：1，他引：1  

梁哲军  陶洪斌  赵海祯  刘惠民  王璞  卫霞 《华北农学报》2009,24(2)

通过模拟土壤水分亏缺试验,研究了玉米在土壤水分亏缺后光合生理的恢复机制.结果表明:不同处理玉米光合生理在复水后30 d内均可以恢复正常生长.轻度亏缺处理玉米叶片气孔导度和蒸腾强度在复水后0～10 d可恢复正常,光合速率和胞间CO2浓度在复水后10～20 d恢复正常,但叶绿素荧光参数(Fv/Fm、Fv/Fo、qP、qN)和叶片光合色素含量的恢复相对较为缓慢.重度水分亏缺处理玉米光合生理指标恢复滞后于轻度亏缺处理.轻度亏缺处理复水后玉米净光合速率的恢复主要受气孔因素影响,重度水分亏缺处理玉米净光合速率的恢复在复水0～10 d主要受非气孔因素影响,复水10 d后主要受气孔因素影响.  相似文献   

小叶白掌变异苗的恢复     

罗为伟  胡庆  段学涛 《江西林业科技》2003,(5):13-15

小叶白掌变异苗的恢复应在25℃一28℃条件下。对4类变异苗，以MS IAA0．1mg／L培养基的效果为好；对5类变异苗则以MS IBA0.3mg/L培养基较好。  相似文献   

牛卵巢的保存与卵巢内卵母细胞采集的研究   总被引：10，自引：0，他引：10  

王锋  钱菊汾 《西北农业学报》2003,12(4):12-16

利用屠宰牛的卵巢,研究了卵巢内(Interior Ovary,IO)卵母细胞的回收方法与影响IO卵母细胞回收数量的因素,以及卵巢保存方法对卵母细胞体外受精后卵裂率与体外发育能力的影响.结果表明抽吸采取表面卵泡卵母细胞以后,用间隔1.6 mm的4个刀片平行排列构成的切割刀,纵横切割秦川牛卵泡期卵巢,其卵母细胞回收数量最高.两次回收平均每个卵巢可获得26.45个A、B级可用卵,较单纯抽吸采卵(5.15个)提高了约4倍.刀距增宽或缩小都会降低卵母细胞的回收数量.牛品种不同对IO卵母细胞的回收数量有显著影响,以中国荷斯坦牛最多(34.25个/卵巢),秦川牛次之(21.75个/卵巢),山丹牛最少(8.25个/卵巢).牛繁殖状态不同对IO卵母细胞的回收数量有显著影响,以卵泡期最多(21.75个/卵巢),黄体期和妊娠期次之(分别为11.75、10.75个/卵巢),老龄退化期最少(4.25个/卵巢).回收的IO卵母细胞直径和透明带外径分别达(126.9±9.98) μm和(151.85±10.39) μm,均较表面卵母细胞(分别为136.05±6.09 μm和160.80 μm±4.23 μm)要小的多(P＜0.01).卵巢保存温度25～29℃与30～37℃对IO卵母细胞体外受精后卵裂率与6～8细胞胚发育率无显著影响(P＞0.05),但保存时间则有显著影响,超过6 h会显著降低卵裂率和6～8细胞胚发育率(P＜0.05).  相似文献   

高压静电回收氯化锌废气设备的研究     

赵道彬  谢仁智  李英华  吴波 《林产化学与工业》1984,(1)

本文用生产规模的单管高压静电设备。对回收氯化锌法活性炭生产过程中产生的氯化锌废气进行了研究;对影响锌回收率的各因子进行了讨论。研究结果表明,工业生产中产生的氯化锌废气可以用高压静电法回收,当二次交流电压为3·5万伏,管内废气流速保持一定值,锌回收率可达98％以上,回收液的浓度29°Be′/36℃。设备性能稳定,运行可靠,不需要冷却水,工艺流程短,运行费用低,经济效果显著,是目前国内同行业中光进的回收设备。  相似文献   

Mortality and recovery of runt white sturgeon (Acipenser transmontanus) in a commercial farm in California, USA     

Georgiadis MP  Hedrick RP  Johnson WO  Gardner IA 《Preventive veterinary medicine》2000,43(4):269-281

We investigated the effect of raising runt white sturgeon (Acipenser transmontanus) separately from dominant fish during the initial stages of grow-out in a commercial farm. Runt fish are poor-growers, have underdeveloped muscle mass, swim slowly and are more-frequently found at the top of the water column. The objective of the study was to describe the mortality and recovery rates (and their determinants) of white-sturgeon runts after separating them from dominant fish. Runt white sturgeon were stocked into twelve 2 m × 2 m rectangular tanks and graded periodically during a follow-up of 46–102 days. Overall mortality rates ranged from 0.3 to 7 dead fish per 1000 sturgeon-days at risk and overall recovery rates from 3.9 to 13.5 recovered fish per 1000 sturgeon-days at risk. Period-specific mortality and recovery rates increased over time. The period-specific mortality rates for all three periods were significantly higher for tanks of runts originating from grow-out tanks with high mortality (p-values: first period = 0.06; second period = 0.09; third period = 0.03), but were similar for tanks of runts of high- and low-mean initial weight. The period-specific recovery rates were significantly higher in runts originating from high-mortality grow-out tanks only for the third period (p = 0.05) but not the first and second periods (p-values = 0.33 and 0.25, respectively). Recovery rates were significantly higher in the higher-mean-weight runts tanks for the first and third period but not for the second (p-values: first period = 0.02; second period = 0.65; third period = 0.06). We concluded that the proportion of runts that recover during a 46–89 day period is substantial (16–58%); therefore, it might be worthwhile growing such fish separately in a fish farm for about three months. Financial analysis showed that this practice was profitable, if the value of white sturgeon fish for the farm exceeded $2.05 per kg.  相似文献