牛奶中氯唑西林残留量的高效液相色谱法测定

为建立高效液相色谱法测定牛奶中氯唑西林残留的方法,牛奶样品用乙腈沉淀蛋白,三氯甲烷反萃取,有机相旋干用流动相溶解,正己烷除脂。0.02mol/L磷酸二氢钾溶液(pH 5.0)-乙腈(68∶32)比例为流动相,C18反相色谱柱分离,紫外检测。结果氯唑西林在15μg/kg～1 000μg/kg范围内呈现良好的线性关系,相关系数大于0.999 0;在15、30、60μg/kg三个添加水平,氯唑西林在牛奶中的平均回收率为70.25%～94.38%,批内变异系数小于8.34%,批间变异系数小于3.52%。方法检出限为5μg/kg,定量限为15μg/kg。表明该检测方法简单、灵敏、可靠,适用于牛奶中氯唑西林残留的分析检测。     

Association of tumor budding with tumor-infiltrating lymphocytes and prognosis in breast cancer patients

AIM: To investigate the relationship of tumor budding with clinicopathologic parameters, tumor-infiltrating lymphocytes (TILs) of tumor microenvironment and the prognosis in breast cancer patients.METHODS: A total of 178 HE section samples were collected from the breast cancer patients treated with surgery in the First Affilated Hospital of Jinan University during Jan. 2012 to Dec. 2016. The tumor budding and stromal tumor-infiltrating lymphocytes were observed under light microscope. The correlation of tumor budding with the clinicopathologic status and TILs were analyzed by χ² test. Kaplan-Meier survival analysis and Log-rank test were used to estimate the disease-free survival (DFS) and overall survival (OS).RESULTS: High tumor budding level was associated with more positive lymph nodes, higher grade, and more lymphovascular invasion. In addition, the patients with higher tumor budding level showed fewer TILs, while the patients with lower tumor budding level had more TILs. Furthermore, the patients with higher tumor budding level had a worse disease-free survival and overall survival than those with lower tumor budding level.CONCLUSION: Tumor budding is significantly associated with adverse clinicopathological characteristics of breast cancer and negatively correlated with TILs. Therefore, tumor budding may serve as a potential biomarker to predict the prognosis of breast cancer.     

Effects of puerarin on apelin-12, angiotensin II,NO and blood pressure in renovascular hypertensive rat

AIM: To investigate the effects of puerarin on blood pressure in renovascular hypertensive rats, and to measure puerarin-induced changes of apelin-12, angiotensin II (Ang II) and nitric oxide(NO), the factors related to development of hypertension. METHODS: Sixty-five male Sprague-Dawley rats were used, of which 8 rats were randomly selected as sham operation group, and the remaining were used to make two-kidney, one-clip model. The rats that met the criterion for Goldblatt hypertensive rat model were randomly allocated into 5 groups: high-, middle- and low-dose puerarin groups, captopril group, and model group. The drugs were administered for 6 weeks. Blood pressure was measured every 2 weeks. Six weeks after treatment, all rats were sacrificed under deep anesthesia. Blood and kidney samples were collected. The level of apelin-12 in serum and kidneys was detected by ELISA. The level of Ang II in plasma and kidneys was measured by radioimmunoassay. NO level in serum was examined by nitrate reductase assay. RESULTS: Puerarin had an antihypertensive effect in a dose-dependent manner. Marked decreases in the level of serum apelin-12 in high- and middle-dose puerarin groups were observed(P<0.01). Puerarin at low dose did not cause obvious change in the content of apelin but still reached significant level (P<0.05). As the dose of puerarin went up, the level of apelin-12 in the kidneys was gradually decreased. Puerarin at high and middle doses obviously reduced the level of AngII in plasma, while purarin at low dose did not produce any significant effects. Puerarin at high and middle doses markedly increased the level of NO in serum, but puerarin at low dose did not induce any significant changes. CONCLUSION: Puerarin has an antihypertensive effect, and its mechanism may be related to inducing the changes of apelin, Ang II and NO, and regulating the balance among those factors.     

镉胁迫对油菜根系生理特性的影响

采用水培体系,对幼苗期油菜根系进行不同浓度(1,5,10,25,50 mg/L)的Cd2+胁迫,胁迫1,3,6,9 d后测定其若干相关生理特性指标,研究镉对油菜根系生理特性的影响。研究结果表明:Cd2+胁迫下油菜根系的电解质相对外渗率、MDA和游离脯氨酸的含量都随着Cd2+处理浓度的增加而增大,并且各处理浓度与对照差异性显著(P<0.05);可溶性蛋白、可溶性糖含量随着Cd2+处理浓度的增加先升高后降低,低浓度(小于5 mg/L)有明显的促进作用;且各指标随着处理时间的延长逐渐上升。SOD酶活性在胁迫3 d后,随处浓度和处理时间的延长先升高后降低,APX、CAT和POD酶活性随着Cd2+胁迫浓度的升高,先升高后降低,但各种抗氧化酶对浓度的敏感性不同,SOD>APX>CAT>POD。综上述,镉胁迫对油菜根系生长有一定的伤害,使得根系细胞膜透性增加,膜脂过氧化加重,根系利用自身渗透调节物质和抗氧化酶活性升高来调节并适应环境,但是高浓度的镉环境使得根系细胞中积累较多的活性氧等自由基而严重伤害细胞,可溶性蛋白含量以及抗氧化酶活性下降,影响根系生长。     

香花崖豆藤的园林应用初探

介绍了香花崖豆藤的园林美化、生态及经济等园林应用价值,并讨论了其在园林绿化中的应用前景。     

DA－6对干旱胁迫下花生生理及生长指标的影响

通过盆栽试验研究花生干旱胁迫条件下盛花期使用DA-6对生理指标和生长指标的影响.结果表明,使用DA-6能减缓干旱胁迫对花生造成的伤害,增强花生光合产物的积累和水分利用能力,提高花生的养分吸收量和荚果产量.与干旱胁迫对照比较,喷施DA-6叶片的光合速率和蒸腾速率增加48.9%和26.6%,土施DA-6叶片的光合效率和蒸腾速率增加47.8%和68.0%,喷施后水分利用效率有明显提高;另外,喷施和土施DA-6,脯氨酸含量显著降低35.1%和62.0%,MDA含量下降44.9%和34.2%,花生荚果的产量增加7.9%和18.3%,籽粒粗脂肪含量也有显著提高.综合来看,喷施DA-6提高水分利用效率和花生籽粒粗脂肪含量的效果最好.因此,DA-6可作为节水农业上具有应用潜力的可提高作物抗旱性的新型化学调节物质.     

基于LAMP方法的苜蓿疫霉根腐病菌分子检测研究

苜蓿疫霉根腐病菌是我国检疫性有害生物之一.但是,目前国内尚无检测标准.笔者针对该病菌特异分子标记,设计了LAMP引物,建立了苜蓿疫霉根腐病菌恒温快速检测方法(巳申请发明专利).该方法快速、准确、无需PCR仪,很好地满足了口岸检疫部门的检测要求.     

半湿润雨养农业区油菜冠层反射光谱与覆盖度的相关分析

以黄土高原甘肃庆阳西峰为半湿润雨养农区典型代表,分析研究油菜营养生长阶段苗期、蕾苔期和生殖生长阶段初期开花始期的冠层反射光谱特征与其覆盖度的相关性.结果表明,这几个时期油菜覆盖度与450、550、650、850、1650nm波段反射率存在明显的相关关系,尤其是蕾苔期,相关关系达到极显著水平.另外,研究了10个常用的植被指数同油菜覆盖度间的相关关系,这10个植被指数同油菜覆盖度存在着极显著的相关关系,相关性高于同单波段反射率间的关系.并且,利用各时期最优的2个植被指数建立了油菜覆盖度线性及非线性回归监测模型,方程的拟合度都较好.苗期,线形和非线性回归模型拟合程度差异不大,蕾苔期,以线性方程拟合精度较其它方程高;开花始期则以指数模型拟合精度高.     

柑桔木虱的生物防治研究进展

本文阐述了国内外对柑桔木虱起主要控制作用的主要天敌种类,包括寄生性天敌、捕食性天敌以及一些病原微生物等,讨论了今后持续控制柑桔木虱的控制措施的发展趋势。     

种子活力和作物产量

\t\t\t\t\t目的\t\t\t\t\t种茎质量是木薯增产的主要限制因素之一,研究筛选木薯种茎活力评价指标,可为木薯种茎处理技术提供理论依据。\t\t\t\t\t\t\t\t\t\t\t\t\t方法\t\t\t\t\t选用华南8号和南植199木薯为材料,从植后150 d开始,每隔30 d采样1次种茎,共采集6次,分别在正常供水和干旱胁迫条件下,开展种茎发芽试验;同时测定发芽前的种茎生理生化指标。通过主成分分析得到不同采样期的种茎活力综合得分,并进行种茎生理生化指标与综合活力得分的相关性分析。\t\t\t\t\t\t\t\t\t\t\t\t\t结果\t\t\t\t\t6次采样的种茎活力综合得分差异较大;华南8号种茎活力综合得分与丙二醛含量和含水量呈显著负相关(P<0.05),与淀粉含量呈极显著正相关(P<0.01),与可溶性蛋白和游离脯氨酸含量呈显著正相关(P<0.05);南植199种茎活力综合得分与丙二醛含量呈极显著负相关(P<0.01),与过氧化氢酶活性、淀粉含量、游离脯氨酸含量、含水量相关系数较高,但未达显著水平(P>0.05)。\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t结论\t\t\t\t\t推荐种茎的丙二醛含量作为木薯种茎活力的评价指标。\t\t\t\t