谈冬季树木防寒

受气候因素的影响,丹东市近年来连续出现倒春寒现象,部分不耐寒树种及早期放叶,开花的树木,在早春经常遭受冻害或出现"生理干旱"现象。本文从生产实践出发,论述了受害树木的部位及受害原因,并提出具体的保护措施。     

白毛茶树早春受低温冻害的原因与防御补救措施

茶树原属亚热带植物,抗寒能力较弱,其能承受的最低温度在-7～-15℃,各品种间差异显著。白毛茶树是叶用作物,其1～2月份新梢萌发期极易受"倒春寒"的影响,轻则幼嫩芽叶卷曲、变褐、变焦,茶叶减产;重则茶树生长势衰落,枝枯叶落,甚至死亡。通过对白毛茶冻害研究,提出了相应的对策,供生产参考。     

大叶女贞耐寒性研究——基于2009年河北省邢台市大叶女贞冻害调查分析

[目的]研究2009年初冬暴雪对邢台市区栽植的大叶女贞的冻害情况。[方法]采用重点区域普查法对邢台市主城区的主要干道、公园、游园内种植的大叶女贞冻害情况逐一调查并分析。[结果]种植年限、栽植环境和温度骤降是造成冻害的主要原因。[结论]选用耐寒品种和大规格苗,选择适宜栽植环境,提高养护管理水平等可以提高大叶女贞的耐寒性。     

S100B protein and neuron-specific enolase as predictors of postoperative cognitive dysfunction in aged dogs: a case-control study

ObjectivePostoperative cognitive dysfunction (POCD) may be related to brain injury. S100B protein and neuron-specific enolase (NSE) have been investigated as potential biochemical markers of neural cell injury in animals and humans. This study aimed to investigate the association between POCD, brain injury and serum concentrations of S100B and NSE after periodontal surgery in aged dogs.Study designProspective observational animal study.AnimalsA total of 24 male and female dogs undergoing periodontal surgery.MethodsDogs were separated into two groups based on age: control group, 10 dogs ≤ 8 years and aged group, 14 dogs > 8 years. Cognitive function was measured preoperatively and on the seventh postoperative day using the Canine Cognitive Dysfunction Rating scale and the Age-Related Cognitive and Affective Disorders scale. S100B protein and NSE serum concentrations were measured before and immediately after the surgery.ResultsPOCD was not observed after surgery in the present study. Serum concentrations of S100B and NSE were increased postoperatively in the control group but not in the aged group (p = 0.04 and 0.03, respectively). Preoperative S100B serum concentrations were significantly higher in the aged group (p = 0.01).ConclusionsThere was no association between POCD and high concentrations of S100B and NSE in dogs. However, increased postoperative serum concentrations of S100B and NSE were found in the control group after surgery, an effect that may indicate neural damage.Clinical relevanceThe results suggest that anesthesia and oral surgery are associated with higher postoperative serum concentrations of S100B and NSE in dogs ≤ 8 years old, which may indicate neural damage. Serum concentrations of S100B were elevated in aged dogs before anesthesia, a finding that might be related to chronic preoperative brain damage.     

宁化县横坑切梢小蠹虫害大发生与气候因子分析

以福建省宁化县为例,调查研究了横坑切梢小蠹的生物学特性、危害规律,分析了其与气候因子的关系,并探讨了对横坑切梢小蠹的防治方法。     

Expression of neutrophil gelatinase-associated lipocalin in a mouse model of ventilator-induced lung injury

AIM：To elucidate the effects of mechanical ventilation on the expression of neutrophil gelatinase-associated lipocalin (NGAL) in mice for identifying NGAL as a novel and potential biomarker for ventilator-induced lung injury (VILI). METHODS：Mice were subject to different strategies of mechanical ventilation to establish the mouse model of VILI. The changes of NGAL mRNA level were detected by real-time RT-PCR. At the same time, the protein levels of NGAL in the mouse lung tissues, serum and bronchoalveolar lavage fluid(BALF) were observed by Western blotting analysis. To evaluate the spatial localization of NGAL expression, triple immunohistochemical staining was conduced in the lung tissue samples from the mouse VILI model. RESULTS：NGAL expression was increased in different ventilation groups, and the levels were significantly elevated in VILI groups. The higher level of NGAL expression was observed in the high-peak inflation pressure group and high-volume group. These data implied an important role of NGAL as a sensor in mechanical stimulus and involved in the pathogenesis of VILI. CONCLUSION：NGAL is a potential and novel biomarker for the early prediction of VILI. Monitoring the changes of NGAL in serum and BALF is helpful to diagnose the patients with high risk of VILI.     

牛磺酸对脂多糖诱导的小鼠肝脏损伤的缓解作用

本试验旨在研究牛磺酸对脂多糖(LPS)诱导的小鼠肝脏损伤的缓解作用。选用30只体重(22±3)g的ICR雄性小鼠,随机分为3组(每组10只小鼠,n=10):对照组和LPS组饲喂基础饲粮,牛磺酸组在基础饲粮中添加2.5%的牛磺酸。饲喂1周后LPS组和牛磺酸组小鼠腹腔注射10 mg/kg的LPS(LPS溶解于生理盐水,注射剂量为0.2 mL/只),对照组小鼠腹腔注射等体积的生理盐水。LPS注射24 h后,各组小鼠眼眶采血并处死,采集肝脏。血液用于血清谷丙转氨酶(ALT)和谷草转氨酶(AST)活性的测定,肝脏称重后检测氧化应激参数,抗氧化基因及转录因子E2相关因子2(Nrf2)、Kelch样ECH相关蛋白(Keap1)的相对表达量。结果表明:1)LPS处理显著升高了小鼠的肝脏指数(P0.05),而添加牛磺酸显著抑制了由LPS引起的肝脏指数升高(P0.05)。2)LPS处理显著增加了血清ALT和AST活性(P0.05),添加牛磺酸后抑制了血清ALT和AST活性的增加,且其AST活性达到对照组水平(P0.05)。3)LPS组小鼠肝脏出现明显的损伤,而牛磺酸组小鼠肝脏组织损伤较轻。4)与对照组相比,LPS组小鼠肝脏丙二醛(MDA)含量显著上升(P0.05),谷胱甘肽过氧化物酶(GPx)活性显著降低(P0.05),而牛磺酸组上述指标未发生显著变化(P0.05)。5)牛磺酸显著缓解了LPS对肝脏GPx1和Nrf2表达的抑制作用(P0.05)。综上所述,饲粮中添加2.5%的牛磺酸对LPS诱导的小鼠肝脏损伤起到了一定的缓解作用。     

Chilling stress tolerance of two soya bean cultivars: Phenotypic and molecular responses

Chilling stress is a major factor limiting the yield of soya bean [Glycine max (L.) Merr.] on a global scale. However, the regulatory network that controls the chilling response of soya bean remains unclear. In the present study, phenotyping and quantitative analyses of miRNAs in soya bean under chilling stress were carried out to determine the impact of environmental constraints on soya bean productivity. Measurements done during soya bean growth in chilling along with the results of field trials indicated that the cultivars Augusta and Fiskeby V responded differently to low temperatures. Although chilling affected the reproductive development of both cultivars, the final seed output remained unchanged. The differential expression of miR169, miR319, miR397 and miR398 under cold stress was detected using ddPCR. Upon chilling in the reproductive stage, we found that these miRNAs had contrasting expression profiles in Augusta and Fiskeby V. A set of candidate target genes was predicted based on degradome sequencing data. A negative correlation was found between the expression of miR169, miR319 and miR398 and their targets in the roots of both cultivars. Our work elucidates the impact of chilling stress on the productivity of two soya bean cultivars and reveals the importance of miRNA involvement in the low temperature response.     

尾叶桉受寒害不同处理措施试验初探

对受严重寒害的尾叶桉,采取不同的处理措施,试验发现将栽植当年受寒严重的尾叶桉基部伐除,待重新萌芽留选壮芽培育（第二代）与顶梢自然更新和截干更新处理的在胸径、树高上差异显著,不同处理间风害率也存在显著差异;对受严重寒害的可适当增加施肥用量和追肥次数,以促萌芽更新,有明显的经济效益。