座果剂及使用技术

大多数果树、瓜及茄科类作物，在开花时由于营养生长与生殖生长的矛盾及气温不适、光照不足等原因，往往开花不结果或结出的幼果很快脱落，生产上俗称生理落果。研究认为，营养生长过旺，花器得不到足够的养料，若外界温度过低或过高就易造成开花不受精或受精不良，导致不结果或种子、果实发育不良。正常情况下，雌雄花受精形成种子或果实，其内源促进型激素含量明显增加，从而将叶片中产生的光合产物调运到花或幼果中。在养料不足或不利条件下，不受精或受精不良可造成促进型内源激素含量偏低，花和幼果调运光合产物的能力降低，它们因得不…     

疫苗发展的将来趋势:应用可控释放系统的单剂疫苗

<正>得益于新技术的发展,高效力易释放疫苗的研制成为一个新的研究领域。特别是多剂疫苗到单剂疫苗的转化是一个很重要的进步,它可能导致疫苗接种率的改善并降低接种成本。 要完全免疫抵抗百日咳、白喉、破伤风、脊髓灰质炎、乙型肝炎等疾病,须连续注射三针疫苗。在许多发展中国家,接种第一针后没有继续接种的比例可高达70％。漏种原因很多:得不到有效的疫苗、家长不清楚有些疫苗需多次接种、对接种不信     

Protective effects of DIDS against ethanol-induced gastric mucosal injury in rats

The compound 4,4＇-diisothiocyanostilbene-2,2＇-disulfonic acid （DIDS） is an efficient anion exchanger inhibitor that can block the activities of anion exchanger 2 （AE2）, which plays an indispensable role in gastric acid secretion. DIDS also has potent anti-oxidative and antiapoptosis activities. This study aimed to investigate the effect of DIDS on ethanol-induced mucosal damage in rats and to evaluate the underlying mechanisms that mediate the action of the compound. The rats received 1 ml of absolute ethanol or saline orally. DIDS [50 mg/kg intravenous （i.v.）] was given 5 min before ethanol administration. Gastric lesions were evaluated macroscopically, microscopically, and electron microscopically at 60 min after ethanol challenge. Gastric myeloperoxidase （MPO） activity, malonyldialdehyde （MDA） level, prostaglandin E2 （PGE2） synthesis, and cyclooxygenase-2 （COX-2） expression were assessed. For the evaluation of the effect of DIDS on gastric acid secretion, histamine-stimulatory gastric acid secretion was examined with or without pretreatment of DIDS （50 mg/kg; i.v.）. Ethanol-induced gastric lesions were characterized by increasing gastric MDA level, MPO activity, and COX-2 expression, and decreasing PGE2 synthesis. It was found that DIDS significantly reduced the extent of gastric mucosal damage and reversed tissue MDA level and MPO activity. DIDS further enhanced the expression of COX-2 and reversed the decrease of PGE2. Our results suggested that DIDS is beneficial in rat model of gastric injury through mechanisms that involve inhibiting inflammatory cell infiltration and lipid peroxidation and up-regulating the COX-2/PGE2 pathway.     

血管扩张剂治疗重症妊高征21例

血管扩张剂治疗重症妊高征２１例刘红，王连云山东平原县人民医院２５３１００１９８７年１月至１９９１年１月我院住院治疗的重度妊高症患者共３０４例，其中２１例经足量硫酸镁治疗后临床症状不缓解、平均动脉压＞１８．７Ｋｐａ，同时使用血管扩张剂治疗，取得较好效果...     

构树果实对南亚实蝇雌虫的引诱效果及主要引诱成分分析

【目的】南亚实蝇被多个国家列为检疫性害虫,其雌虫在野外被发现取食构树果实。本研究拟初步明确构树果实对南亚实蝇雌虫的引诱效果及其主要引诱成分。【方法】通过室内诱捕试验,测试构树果实对南亚实蝇雌虫的引诱效果;采用气质联用仪(GC-MS)与Y型嗅觉仪,测定构树果实中引起南亚实蝇雌虫行为反应的成分。【结果】构树果实对南亚实蝇雌虫的诱捕率高达81.11%;从构树果实气味中测定出29种挥发性成分,其中,0.500 mg·mL^-1的2-正戊基呋喃、0.005 mg·mL^-1的反-2-己烯醛和0.050 mg·mL^-1的正庚醛能显著引起南亚实蝇雌虫的趋向行为。【结论】构树果实具有作为南亚实蝇雌虫食诱剂的潜力,构树果实中的2-正戊基呋喃、反-2-己烯醛和正庚醛可能是引诱南亚实蝇雌虫的主要成分。