中国塔叶苔属及其新分布

塔叶苔属为１８９４年由Ｆ;ｓｔｅｐｈａｎｉ建立的单种属,即塔叶苔。以前该属在我国的分布仅见于台湾,福建,云南和四川,现见于江西省,为该属植物的新记录。塔叶苔的配子体和孢子体表明,它宜被作为大萼苔科内的一个亚科处理,在亲缘关系上与叉苔目较近。     

重庆彭水发现务川臭蛙

2022年7月,在重庆市彭水苗族土家族自治县新田镇调查到2只臭蛙,经比较形态特征确认为臭蛙属（Odorrana）物种。基于线粒体16S rRNA基因片段构建的臭蛙属部分物种的贝叶斯和最大似然系统发育树显示,这2只臭蛙和模式产地贵州省务川仡佬族苗族自治县的务川臭蛙（O. wuchuanensis）聚为一支,具有较高的支持率,贝叶斯后验概率为0.99、最大似然超快速引导支持（2 000次重复）自展值为95%。综合形态特征和系统发育分析,确认此2只臭蛙为务川臭蛙,系重庆市首次记录。务川臭蛙分布范围较为狭窄,此前仅记录于贵州省务川县、沿河土家族自治县、荔波县以及湖北省建始县和广西壮族自治区环江毛南族自治县。务川臭蛙在重庆彭水的发现,确认了该物种在武陵山和大娄山脉重庆段的分布。彭水发现的务川臭蛙1雄1雌,雄性体长81.3 mm,大于模式标本的最大体长,大于湖北建始县种群雄蛙体长;雌性体长87.1 mm,在模式标本的体长范围内,小于建始县种群雌蛙体长。线粒体16S rRNA基因的遗传分化分析显示,重庆市彭水苗族土家族自治县的务川臭蛙样本和模式产地的样本没有遗传分化,遗传距离为0。务川臭蛙在重庆市的...     

撂荒年限对陕北黄土区山地枣林深层土壤有机碳的影响

以陕西省延安市延川县齐家山红枣试验示范基地不同撂荒年限山地枣林(Ziziphus jujuba Mill.)为研究对象,采用空间代替时间的方法,研究该地区0～340 cm土壤有机碳的分布特征以及撂荒年限对有机碳分布的影响.结果显示:研究区土壤有机碳含量及有机碳储量具有明显的表聚现象;不同撂荒年限土壤有机碳储量差异显著,...     

应用基因组原位杂交及RFLP标记鉴定小麦中的大麦染色体

用生物素（Biotin-6-dUTP)标记的大麦Betzes基因组DNA作探针,以普通小麦中国春总DNA作封阻进行基因组原位杂交（Genomeinsituhybridization,简称GISH）,从13株小麦-大麦杂交后代中鉴定出2个含有3条大麦Betzes2H染色体的材料（2n＝43）;2个2H单体异代换系（2n＝42）;7个2H二体异代换系（2n＝42）。用已定位在小麦第2部分同源群短臂上的探针psr131进行RFLP分析,结果表明大麦Betzes、代换系A5有1条区别于小麦中国春的特异带,A     

滇东南丫蕊花属(百合科)一新种及其生物地理学意义

报道了云南东南部金平县五台山丫蕊花属(百合科)一新种,并讨论了其生物地理学意义     

Genetic transformation of green-colored cotton

Summary This study reports an Agrobacterium-mediated transformation of green-colored cotton (Gossypium hirsutum L.). A tissue culture procedure was optimized to induce callus formation from hypocotyl explants and subsequent differentiation into the embryogenic type. Callus formation could be induced by growing explants on Murashige and Skoog medium containing 2,4-dichlorophenoxyacetic acid and kinetin. Among the four genotypes studied, embryogenic calli and plant regeneration were observed only in var. G9803. Agrobacterium-mediated transformation of G9803 with the fiber-specific expansin gene GhExpl was achieved based on the establishment of these tissue culture methods. A total of 32 individual regenerants resistant to kanamycin were generated within 7 mo., with a transformation frequency of 17.8%. Transformation was confirmed by Southern blot analysis and RT-PCR. These results represent the first step towards genetic manipulation of the colors and fiber quality of green-colored cottons by biotechnology. These authors contributed equally to this work     

秋茄次生木质部的生态解剖学研究

为了探讨秋茄(Kandelia obovata Sheue et al.)次生木质部的形态解剖和数量解剖特征变化对不同红树林生境的生态适应意义,采用光学显微镜(LM)、扫描电镜(SEM)、透射电镜(TEM)和激光共聚焦显微镜(LSCM)对深圳福田红树林自然保护区内7个秋茄种群的次生木质部解剖特征进行观测,并对种群样地的土壤盐分含量、pH值和土壤养分含量进行测定。结果显示,(1)7个秋茄种群的次生木质部具有一些共同形态解剖特征:具纤维状导管和环管管胞;许多导管壁的微观结构(如管壁附物、穿孔板附物和螺旋雕纹等)有利于提高水分输导的高效性和安全性,以适应潮间带生境;(2)应用逐步回归分析法对秋茄次生木质部数量解剖特征和土壤理化因子的关系进行分析发现,随着土壤Na+、土壤全盐量增高,秋茄次生木质部导管分子趋向于"大型化"。"大型化"导管有利于水分输导,但降低了安全性。在土壤盐离子含量越高、秋茄导管分子越大其水分输导安全性越低的情况下,推测可能有其它机制保证秋茄导管水分输导的安全性。     

Anterior Subcutaneous versus Submuscular Transposition of the Ulnar Nerve for Cubital Tunnel Syndrome: A Systematic Review and Meta-Analysis

Objective

To pool reliable evidences for the optimum anterior transposition technique in the treatment of cubital tunnel syndrome by comparing the clinical efficacy of subcutaneous and submuscular anterior ulnar nerve transposition.

Methods

A comprehensive search was conducted in PubMed MEDLINE, Cochrane Library, EMBASE, Web of Science, OVID AMED, EBSCO and potentially relevant surgical archives. Risk of bias of each included studies was evaluated according to Cochrane Handbook for Systematic Reviews of Interventions. The risk ratio (RR) and 95% confidence intervals (CI) were calculated for the clinical improvement in function compared to baseline. Heterogeneity was assessed across studies, and subgroup analysis was also performed based on the study type and follow-up duration.

Results

Three studies with a total of 352 participants were identified, and the clinically relevant improvement was used as the primary outcomes. Our meta-analysis revealed that no significant difference was observed between two comparison groups in terms of postoperative clinical improvement in those studies (RR 1.04, 95% CI 0.86 to 1.25, P = 0.72). Meanwhile, subgroup analyses by study type and follow-up duration revealed the consistent results with the overall estimate. Additionally, the pre- and postoperative motor nerve conduction velocities were reported in two studies with a total of 326 patients, but we could not perform a meta-analysis because of the lack of concrete numerical value in one study. The quality of evidence for clinical improvement was ‘low’ or ‘moderate’ on the basis of GRADE approach.

Conclusions

Based on small numbers of studies with relatively poor methodological quality, the limited evidence is insufficient to identify the optimum anterior transposition technique in the treatment of cubital tunnel syndrome. The results of the present study suggest that anterior subcutaneous and submuscular transposition might be equally effective in patients with ulnar neuropathy at the elbow. Therefore, more high-quality randomized controlled trials with standardized clinical improvement metrics are required to further clarify this topic and to provide reproducible pre- and postoperative objective outcomes.