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31.
This paper reports 24 newly discovered specimens of 21 species made by Charles Darwin in Argentina, Australia, Brazil, Chile, Ecuador and Uruguay while on the 1831–1836 voyage of HMS Beagle. They have been found in Cambridge University Herbarium and the herbaria of the Missouri Botanical Garden, Natural History Museum, London, New York Botanical Garden and the Royal Botanic Gardens, Kew, since the earlier publications of Porter. Included are type specimens of Calceolaria darwinii (isotype; = C. uniflora), Cuscuta gymnocarpa (holotype and isotypes), C. sandwichiana var. mimosae (isolectotypes = C. gymnocarpa), Ephedra frustillata (lectotype and isolectotypes), Ourisia breviflora (isolectotype), Polypodium paleaceum (syntype?; = Ctenitis sloanei) and Urera gaudichaudiana (holotype; = Laportea aestuans). © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 12–18.  相似文献   
32.
The number of genetic studies that use preserved specimens as sources of DNA has been steadily increasing during the last few years. Therefore, selecting the sources that are more likely to provide a suitable amount of DNA of enough quality to be amplified and at the minimum cost to the original specimen is an important step for future research. We have compared different types of tissue (hides vs. bones) from museum specimens of Iberian lynx and multiple alternative sources within each type (skin, footpad, footpad powder, claw, diaphysis, maxilloturbinal bone, mastoid process and canine) for DNA yield and probability of amplification of both mitochondrial and nuclear targets. Our results show that bone samples yield more and better DNA than hides, particularly from sources from skull, such as mastoid process and canines. However, claws offer an amplification success as high as bone sources, which makes them the preferred DNA source when no skeletal pieces have been preserved. Most importantly, these recommended sources can be sampled incurring minimal damage to the specimens while amplifying at a high success rate for both mitochondrial and microsatellite markers.  相似文献   
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向刚  容丽 《广西植物》2022,42(Z1):99-104
自2017年参加“国家标本资源共享平台”植物子平台以来,贵州师范大学地理与环境科学学院植物标本室除了数字化植物标本以外,还挖掘、整理了贵州师范大学植物分类学、植物地理学的建设和发展历程。经过3年的艰苦努力,最后向中国数字植物标本馆(CVH)提供了10 044份信息齐全的植物标本。通过此次植物标本数字化工作,彻底摸清了贵州师范大学地理与环境科学学院植物标本的家底,盘活了标本室的库存,使得老一辈植物地理学家黄威廉等老先生60余年的科研成果重新展现在世人面前。通过植物标本的数字化工作,挖掘整理出老一辈精彩的植物标本采集史和学术故事。在标本数字化的过程中,学生和老师都对植物标本以及植物标本背后的故事有了新的认识,对植物标本数字化的重要性和必要性也有了更深的体会。  相似文献   
35.
目的:探讨混合甲醛固定液固定大肠癌淋巴结标本的最佳免疫组化效果。方法:采用不同pH值(6.0、7.0、8.0)的混合甲醛固定液对39枚大肠癌淋巴结标本进行不同时间(6 h、6 h-12 h、1 d-7 d)的固定处理。以细胞角蛋白20(CK20)为目标抗原,运用OIympusdp 70图像采集分析仪抽选出混合甲醛固定液最佳免疫组化染色的pH值及固定时间。结果:经pH值为7.0混合甲醛固定液处理后,阳性率为92.31%,高于经pH值为6.0、8.0的混合甲醛固定液处理后的76.92%、74.36%,且经pH值为7.0、8.0处理后的阳性率比较有统计差异(P0.05)。混合甲醛固定液的固定时间在6 h-12 h时的阳性率为94.87%,高于固定时间为6 h、1 d-7 d处理的30.77%、76.92%(P0.05)。结论:对于大肠癌淋巴结标本,以CK20为目标抗原,选择pH值为7.0的混合甲醛固定液固定6 h-12 h能够得到质量较佳的免疫组化染色效果。  相似文献   
36.
浅部真菌病1948份临床标本的真菌学分析   总被引:8,自引:2,他引:8  
目的 通过对浅部真菌病患者临床送检标本的病原真菌菌种进行系统分析,了解感染及病原真菌的分布情况。方法 采用直接镜检、培养及真菌鉴定等方法对临床送验标本进行检验和鉴定,大部分标本鉴定到种。结果 1948份临床送验标本中,直接涂片镜检阳性率53.41%,培养阳性率40.28%,而镜检+培养的阳性率为66.98%。对上述3种方法的真菌检出率进行比较,均存在显著差异(χ^2检验P均〈0.005)。在培养的1944份标本中,共分离出18个属,36种真菌,其中,红色毛癣菌24.52%、须癣毛癣菌16.48%、白念珠菌12.64%。结论 ①镜检结合培养的阳性率显著高于单一的镜检或培养的阳性率。②在患者即时的真菌镜检阴性时,应选择培养方法进一步检测,不轻易排除浅部真菌病感染可能。③皮肤癣菌居患者浅部真菌病致病菌首位,而白念珠菌及酵母类菌也是重要病原菌。  相似文献   
37.
Specimens of fishes preserved in the Zoological Museum, University of Uppsala, which are believed to have been examined by Linnaeus, are listed. Most of these were originally given to the University in several donations by benefactors of the Academy and were described by Linnaeus in dissertations defended by students. Some specimens, however, are believed to have originated from Linnaeus's own collection. Many of the specimens have type status and this is discussed together with notes on other surviving Linnaean fish specimens.  相似文献   
38.
Biorepository-supported translational research depends on high-quality, well-annotated specimens. Histopathology assessment contributes insight into how representative lesions are for research objectives. Feasibility of documenting histological proportions of tumor and stroma was studied in an effort to enhance information regarding biorepository tissue heterogeneity. Using commercially available software, unique spatial-spectral algorithms were developed for applying automated pattern recognition morphometric image analysis to quantify histologic tumor and nontumor tissue areas in biospecimen tissue sections. Measurements were acquired successfully for 75/75 (100%) lymphomas, 76/77 (98.7%) osteosarcomas, and 60/70 (85.7%) melanomas. The percentage of tissue area occupied by tumor varied among patients and tumor types and was distributed around medians of 94% [interquartile range (IQR)=14%] for lymphomas, 84% for melanomas (IQR=24%), and 39% for osteosarcomas (IQR=44%). Within-patient comparisons from a subset, including multiple individual patient specimens, revealed ≤12% median coefficient of variation (CV) for lymphomas and melanomas. Phenotypic heterogeneity of osteosarcomas resulted in 33% median CV. Uniformly applied, tumor-specific pattern recognition software permits automated tissue-feature quantification. Furthermore, dispersion analyses of area measurements across collections, as well as of multiple specimens from individual patients, support using limited tissue slices to gauge features for some tumor types. Quantitative image analysis automation is anticipated to minimize variability associated with routine biorepository pathologic evaluations and enhance biomarker discovery by helping to guide the selection of study-appropriate specimens.  相似文献   
39.
In Japan during 1996-2004, 21 actinomycete strains that have madurose as the diagnostic cell-wall sugar and show true branching in their substrate and aerial mycelia were isolated from sputa or bronchoalveolar lavage (BAL) fluid of patients with pulmonary infections or who were suspected of having related infections. Chemotaxonomic studies showed that all the isolates belong to the genus Actinomadura. Among them, six and seven strains were classified respectively into clusters of Actinomadura nitritigenes and Actinomadura cremea based on 16S rDNA analyses because their 16S rDNA similarities to those respective species were greater than 99.5%. To our knowledge, this is first report that strains of above two species were isolated from clinical specimens. Neither Actinomadura madurae nor Actinomadura pelletieri strain was isolated, and one new species, Actinomadura chibensis, was proposed; the remaining seven strains were not assigned into any known species, suggesting the presence of another new Actinomadura species.  相似文献   
40.
Blackfoot disease (BFD) is an endemic peripheral vascular disorder resulting in gangrene of the lower extremities, especially the feet, among residents in a limited area on the southwest coast of Taiwan. In the present study, the concentrations of zinc, cadmium, lead, and copper in urine of BFD patients with matched normal controls are investigated by differential pulse anodic stripping voltammetry (DPASV) on a hanging mercury drop electrode (HMDE). The analytical results indicate that urinary copper, cadmium, and lead of the BFD patients are significantly higher than those of the controls. In addition, the patients showed a significantly lower concentration of zinc in the urine than the normal controls. The possible connection of these elements with the etiology of the disease is discussed.  相似文献   
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