枣铁皮病病原鉴定

 枣铁皮病主要为害大枣果实,可导致果实腐烂和提早落果,据症状特点可分为铁皮型和缩果型2种类型。1993~1995年对河北和河南2省6个不同枣区大枣铁皮病病果进行分离、接种和再分离,证实枣铁皮病病原为:链格孢Alternaria alternata(Fr.) Keissler;实腐茎点霉Phoma destructiva Plowr,壳梭孢属一种真菌Fusicoccum sp.3种病原真菌可以单独或混合侵染。     

Effects of serial ultrasound-guided renal biopsies on kidneys of healthy adolescent dogs

Ten healthy mixed-breed dogs were used to evaluate the functional and structural effects of serial ultrasound-guided renal biopsies obtained with an automated biopsy needle. In each dog, one lateral renal cortex was biopsied at 2, 4, and 6 months of age; the other kidney was the control. Five dogs had two tissue cores and five dogs had four tissue cores taken on each biopsy occasion, and one core was examined microscopically. One week before each biopsy and a month after the final biopsy, the glomerular filtration rate (GFR) was determined by renal scintigraphy. Dogs were then euthanized for evaluation of gross and microscopic lesions attributable to the biopsies. There was no difference between GFR values for biopsied kidneys and those of control kidneys ( P >0.05). Microscopic lesions were not identified in biopsies taken at 2 and 4 months, but focal lesions were found in three of 10 specimens taken at 6 months of age. At necropsy, six of 10 biopsied kidneys had small visible capsular scars, and linear tracts <2 mm wide were observed on cut surfaces in six of 10 biopsied kidneys cut transversely into slices 5 mm thick. Discrete light microscopic lesions were observed in 25 of 452 (5.5%) of randomly selected 6-mm-diameter sections of renal cortex from biopsied kidneys. We conclude that serial renal cortical biopsies can be obtained by our method from healthy adolescent dogs with minimal risk of inducing changes that might be confused with those of a progressive renal disease.     

Influence of estrogen on acetylcholinesterase activity in primary cultures of cerebral cells from neonatal rats

To estimate the influence of estrogen on the functional development of the central nervous system during the neonatal period, several doses of estradiol‐17β (E₂) were treated to cultured cells from the cerebral cortex of neonatal rats and the acetylcholinesterase (AChE) activity was examined. E₂ was added to give the following final concentrations: 0, 10^?10, 10^?9, and 10^?8 M. After 72 h of incubation, all cells were obtained from dishes to determine the AChE activity. Although apparent morphological changes were not observed among treatments cultured for 72 h, E₂ suppressed dose‐dependently the spontaneous increase of AChE activity in cerebral cells. Furthermore, a single dose of tamoxifen, an E₂ receptor binding molecule with agonist and antagonist properties, also acted in a similar manner as E₂. These findings suggest that the functional development of the cerebral cortex, at least the cholinergic system, during the neonatal period is regulated by E₂.     

Effect of tillage, cover crop and crop rotation on the composition of weed flora in a sandy soil

The development of integrated weed management strategies requires knowledge of mechanisms that influence compositional changes in weed flora. A 9-year study was initiated in 1988 at Delhi, Canada, on a loamy sand soil to evaluate the effect of tillage systems [conventional (CT) and no-till (NT)] and cover crops (only in NT) on weed density, species composition and associations, and crop yield in a winter wheat ( Triticum aestivum L.)/bean/winter wheat rotation. Three bean types: soyabean ( Glycine max L. Merr.), white bean ( Phaseolus vulgaris L.) and kidney bean ( P . vulgaris L.) were included. The NT system included variations: rye ( Secale cereale L.) or maize ( Zea mays L.) cover crop, volunteer wheat disked after harvest and wheat stubble. Data were collected in 1994, 1995 and 1996. Tillage systems, cover crops and crop type had differential effects on weed densities, species composition and associations. Weed densities were not affected by tillage or cover crops in wheat but, in the beans, densities were greater in the CT than in the NT systems. Various associations of weed species with tillage system, cover crop and crop type were observed. Crop yields were not affected by tillage type or cover crop, except that soyabean yields were highest in plots with cover crops.     

氧化应激在硝基苯致小鼠肾损伤中的作用

为探讨硝基苯对小鼠肾的毒性作用，采用灌胃法对试验小鼠用硝基苯进行染毒，染毒剂量分别为26、52、105mg／kg，每天染毒1次，共30d。于末次染毒后第2d将小鼠脱颈处死，立即取出肾通过相应处理用于抗氧化指标检测及显微和超微结构的观察。结果，染毒小鼠主要表现为近曲小管上皮细胞不同程度水样变性，线粒体肿胀，脊断裂；内质网脱核糖颗粒；细胞核发生形变；肾小球血管内皮细胞肿胀，血管扩张；随着染毒剂量的加大，肾和血清中MDA含量逐渐升高，SOD和GSH—Px酶活性不断降低，与对照组比较，均差异显著（P〈0．05）或极显著（P〈0．01）。结果表明，硝基苯能够诱发小鼠肾细胞发生氧化胁迫，并诱导细胞凋亡的发生。     

四种脊椎动物小脑皮层的显微结构对比

分别就鲫鱼、黑斑蛙、石龙子、小自鼠四种脊椎动物小脑皮质的显微结构做了初步的观察和对比，发现在这四种动物的小脑皮质中，主要含有同样的三种神经细胞：分子层细胞、蒲肯野细胞、颗粒细胞。     

菜豆新品种‘晋菜豆3号’

‘晋菜豆3号’是通过系统选育而成的菜豆新品种。蔓生,平均株高315 cm,花白色,第3 ~ 4节着生第一花序,主蔓可分5 ~ 6条侧枝,幼茎绿色。商品荚绿白色,豆荚长圆条形,荚长28 ~ 33 cm,荚粗1.6 ~ 1.8 cm,荚肉厚,无革质膜,纤维少。豆种金黄色,百粒质量31 g。单株结荚70 ~ 80个,生育期120 ~ 180 d。适于山西春季露地种植。     

Astaxanthin Attenuates Early Acute Kidney Injury Following Severe Burns in Rats by Ameliorating Oxidative Stress and Mitochondrial-Related Apoptosis

Early acute kidney injury (AKI) is a devastating complication in critical burn patients, and it is associated with severe morbidity and mortality. The mechanism of AKI is multifactorial. Astaxanthin (ATX) is a natural compound that is widely distributed in marine organisms; it is a strong antioxidant and exhibits other biological effects that have been well studied in various traumatic injuries and diseases. Hence, we attempted to explore the potential protection of ATX against early post burn AKI and its possible mechanisms of action. The classic severe burn rat model was utilized for the histological and biochemical assessments of the therapeutic value and mechanisms of action of ATX. Upon ATX treatment, renal tubular injury and the levels of serum creatinine and neutrophil gelatinase-associated lipocalin were improved. Furthermore, relief of oxidative stress and tubular apoptosis in rat kidneys post burn was also observed. Additionally, ATX administration increased Akt and Bad phosphorylation and further down-regulated the expression of other downstream pro-apoptotic proteins (cytochrome c and caspase-3/9); these effects were reversed by the PI3K inhibitor {"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002. Moreover, the protective effect of ATX presents a dose-dependent enhancement. The data above suggested that ATX protects against early AKI following severe burns in rats, which was attributed to its ability to ameliorate oxidative stress and inhibit apoptosis by modulating the mitochondrial-apoptotic pathway, regarded as the Akt/Bad/Caspases signalling cascade.