北京地区小麦赤霉病和茎基腐病的病原群体组成

随着北京市小麦种植面积的逐步恢复,小麦赤霉病和茎基腐病的发生范围也逐渐扩大。为明确北京地区小麦赤霉病及茎基腐病的病原群体组成,于2023年从北京市6个区14个采样点采集小麦赤霉病和茎基腐病样品,采用组织分离法得到290株小麦赤霉病菌株及163株小麦茎基腐病菌株。采用翻译延伸因子TEF1-α基因进行分子鉴定,明确了北京地区不同区县小麦赤霉病菌和茎基腐病菌的群体组成。北京地区小麦赤霉病的病原主要是禾谷镰孢Fusarium graminearum和假禾谷镰孢F.pseudograminearum,其中禾谷镰孢占群体总数的92.41%,是整个北京地区的优势致病菌,也是海淀、平谷、顺义、密云和延庆地区的优势致病菌,假禾谷镰孢是怀柔地区的优势致病菌。北京地区小麦茎基腐病的病原主要是假禾谷镰孢(45.40%)和禾谷镰孢(37.42%),还分离出层出镰孢F.proliferatum(1.23%)、中华镰孢F.sinense(7.36%)、锐顶镰孢F.acuminatum(4.29%)、三线镰孢F.tricinctum(3.07%)和木贼镰孢F.equiseti(1.23%)。海淀和密云地区的小麦茎基腐病优势致病菌是假禾谷镰孢,平谷、顺义和延庆地区的优势致病菌是禾谷镰孢。该研究结果为小麦赤霉病和茎基腐病的预测预报和精准防治提供依据。

临床不同病原群体血钾测定结果讨论

目的:调查临床科室不同病原群体血钾水平,探讨不同疾病对血钾的影响,以及重度低钾血症和重度高钾血症的发生机率。方法:将临床住院病人分成11个病原群体,采用离子选择电极法测定血浆钾,并对2003年10月到2005年6月间血浆钾测定结果进行分析统计。结果:宫外孕、产妇群体、消化内科群体、呼吸系统疾病、心血管疾病、泌尿内科、脑外伤、普外手术组明显低于对照组(P<0.001);骨外伤、泌尿外科、肝胆外科组低于对照组(P<0.05)。宫外孕群体组、产妇群体组、呼吸系统疾病组、消化内科疾病、脑外伤组与泌尿外科群体组、消化外科疾病组比较结果有极显著性差异(P<0.001),与骨外伤群体组和普外手术群体组比较有差异(P<0.05);宫外孕群体组和呼吸系统疾病组与心血管疾病组和骨外伤群体组比较有显著性差异(P<0.01);呼吸疾病组、消化内科组与心血管组比较有极显著性差异(P<0.001);普外手术组与泌尿外科组比较有差异(P<0.05);骨外伤组与泌尿外科组比较有差异(P<0.05)。出现极低血钾机率最高的群体依次是消化内科群体2.83%、呼吸系统疾病群体2.25%、脑外伤群体2.23%、泌尿内科群体2.11%。出现极高血钾机率最高的群体是泌尿内科群体0.71%、心血管疾病群体0.61%、呼吸系统疾病群体0.46%和消化内科群体0.45%。结论:住院病人血钾水平偏低,宫外孕、产妇、内科病原群体和脑外伤群体偏低尤为明显。各病原群体间由于病理生理的不同也互有差异。呼吸障碍、肾功能衰竭、重症颅脑外伤、重症消化系统疾患最易出现重度低钾血症;重度高钾血症的发生机率远低于重度低钾血症的机率,且主要出现在肾功能障碍和心功能衰竭。

临床不同病原群体血尿酸降低的机率分析

目的探讨不同疾病对血尿酸的影响,及低尿酸血症的发生机率及临床意义。方法将检查血尿酸的病人分成门诊和和住院两大组,住院病原群体又分13组,分别对各组血尿酸低于120μmol/L进行监测统计。结果低尿酸血症,住院组高于门诊、对照组,在住院组中、心血管、骨伤、消化内科、泌尿内、外科,产妇组发生少,其余科、组均发生多。结论住院病人出现低尿酸血症的机率高于门诊病人。在住院治疗中,重症监护室的危重病人和中重度烧伤病人出现低尿酸血症的机率高于其他病原群体。其次是呼吸系统疾病群体、肝胆外科疾病群体、宫外孕手术群体、颅脑损伤群体、普外手术群体。其他病原群体出现低尿酸血症的机率低于住院病人平均水平。血尿酸降低的幅度与病情严重程度相关。

Replication of clinical hepatitis B virus isolate and its application for selecting antiviral agents for chronic hepatitis B patients

AIM: To establish a cell model harboring replicative clinical hepatitis B virus (HBV) isolates and evaluate its application in individualized selection of anti-HBV agents for chronic hepatitis B (CHB) patients. METHODS: The full-length HBV genomic DNA from 8 CHB patients was amplified by polymerase chain reaction (PCR). All the patients were treated with lamivudine for at least seven months and finally became resistant to lamivudine. The amplified HBV DNA fragments were inserted into pHY106 vectors by Sap Ⅰ?digestion. The recombinant plasmids containing 1.1 copies of HBV genome were transiently transfected into Huh7 cell line, and the levels of HBsAg, HBeAg and intercellular HBV replicative intermediates were determined by ELISA and Southern blot analysis, respectively, with or without lamivudine and adefovir treatment. The antiviral treatment with adefovir was administered to the patients and analyzed in parallel. RESULTS: A total of 25 independent HBV isolateswere obtained from the sera of 8 patients, each patient had at least two isolates. One isolate from each individual was selected and subcloned into pHY106 vector, including 5 isolates with YVDD mutation and 3 isolates with YIDD mutation. All recombinant plasmids harboring HBV isolates were transfected into Huh7 cells. The results indicated that HBV genome carried in HBV replicons of clinical HBV isolates could effectively replicate and express in Huh7 cells. Adefovir, but not lamivudine, inhibited HBV replication both in vitro and in vivo, and in vitro inhibition was dose-dependent. CONCLUSION: The novel method described herein enables individualized selection of anti-HBV agents in clinic and is useful in future studies of antiviral therapy for CHB.

Gibbago trianthemae Simmons, a Biocontrol Agent of Horse Purslane Weed： Research and Prospect

Trianthema portulacastrum L. （commonly known as horse purslane） is a noxious weed of several economically important field crops in tropical regions of the world. An intensive work on the screening of the biocontrol agents was accomplished through in vitro epidemic study to control weed populations. The foliar disease symptoms on infected weed plants caused by fungal pathogens represented as round to irregular maroon spots with dark borders and the epidemic was identified as leaf spot disease. The pathogen allied with the infection of horse purslane was isolated from infectious propagules by inoculation of leaf bites on a nutrient medium, potato dextrose agar （PDA）. The causal agent of leaf spot was confirmed as Gibbago trianthemae Simmons by Koch＇s postulates. The mycoherbicide ability of G. trianthemae has been examined through visual （standard area diagram） and statistical methods （analysis of variance using the Microsoft Office Excel-Data Analysis Tool Pack 2007）. The results revealed that the pathogen causes significantly （P 〈 0.05） severe infection on host weed and destructs the weed population by leaf spot diseases. The findings of the research suggested that the isolate G. trianthemae is highly virulent and host-specific, and recommended for further studies as a promising biocontrol agent against horse purslane weed.