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991.
蟾酥为名贵中药,在成方制剂中用量少,疗效显著,有必要对其质量进行监测。本文总结了常用的蟾酥分析方法。  相似文献   
992.
为筛选海南夏秋季苦瓜生产上适宜的嫁接砧木,以琼3号苦瓜为接穗,以自根苗为对照,研究了不同砧木对海南夏秋季嫁接苦瓜生长、产量、品质以及抗性的影响。试验结果表明:海南丝瓜和海砧1号嫁接苗与自根苗相比,均表现为生长势强、抗病性好、品质优、采收期延长17 d,增产30%以上,可作为海南夏秋季苦瓜嫁接砧木在生产上大面积推广;青雪王子可作为备选砧木品种进行推广应用。  相似文献   
993.
通过试验对福建省主要几个姬松茸菌株在有机栽培过程中的菌丝生长状况、生育期、子实体产量和生物学性状等方面进行比较,结果表明本地品种和姬松茸11号是适合在莆田市进行有机栽培的优良菌株。  相似文献   
994.
Ocular pathogens cause many painful and vision‐threatening diseases such as infectious keratitis, uveitis, and endophthalmitis. While virulent pathogens and pathobionts play important roles in disease pathogenesis, the scientific community has long assumed disruption of the ocular surface occurs prior to microbial colonization and subsequent infection. While nonpathogenic bacteria are often detected in corneal and conjunctival cultures from healthy eyes, cultures also frequently fail to yield growth of common ocular pathogens or nonpathogenic bacteria. This prompts the following question: Is the ocular surface populated by a stable microbial population that cannot be detected using standard culture techniques? The study of the microbiome has recently become a widespread focus in physician and veterinary medicine. Research suggests a pivotal symbiotic relationship with these microbes to maintain healthy host tissues, and when altered is associated with various disease states (“dysbiosis”). The microbiota that lives within and on mammalian bodies have long been known to influence health and susceptibility to infection. However, limitations of traditional culture methods have resulted in an incomplete understanding of what many now call the “forgotten organ,” that is, the microbiome. With the introduction of high‐throughput sequencing, physician ophthalmology has recognized an ocular surface with much more diverse microbial communities than suspected based on traditional culture. This article reviews the salient features of the ocular surface microbiome and highlights important future applications following the advent of molecular techniques for microbial identification, including characterizing ocular surface microbiomes in our veterinary species and their potential role in management of infectious and inflammatory ocular diseases.  相似文献   
995.
996.
2014~2015年在镉污染土壤上进行镉低积累西瓜品种筛选试验,对参试西瓜品种的茎蔓、叶片、根和果实中镉含量进行检测分析。试验结果表明:茎蔓中镉平均含量为0.0570mg·kg~(-1),叶片中镉平均含量为0.0621mg·kg~(-1),根中镉平均含量为0.0548mg·kg~(-1),果实中镉平均含量为0.0092mg·kg-1。参试西瓜品种果实中镉的含量均低于GB18406.1—2001农产品安全质量无公害蔬菜安全标准〔镉(Cd)≤0.05mg·kg~(-1)〕;西瓜各部位镉积累量:叶茎蔓根果实;在土壤镉含量0.310~9.480mg·kg~(-1)范围内,随着土壤中镉含量增大,西瓜果实中镉含量有逐渐增多的趋势。湘西瓜11号(洞庭1号)、湘西瓜19号(洞庭3号)、金丽黄、绿虎、蜜童、东方娇子、泉鑫2号、黑迷人等8个西瓜品种,在土壤镉含量9.480mg·kg-1以下均可作为镉污染地区耕地修复及种植结构调整的优选品种。  相似文献   
997.
研究不同施肥方式下马铃薯生长发育特点以及产量表现。试验结果表明,基肥+水肥一体化施用、基肥+3次追肥处理效果比较好,马铃薯产量较高,特别是基肥+水肥一体化施用的效果更明显、产量更高、效益更好,值得在生产中推广。  相似文献   
998.
ESBL/AmpC‐producing Escherichia coli is increasingly isolated from humans and animals worldwide. The occurrence of ESBL/AmpC‐producing E. coli was studied in food‐producing animals in Finland, a country with a low and controlled use of antimicrobials in meat production chain. A total of 648 cattle, 531 pig, 495 broiler and 35 turkey faecal samples were collected from four Finnish slaughterhouses to determine the presence of extended‐spectrum β‐lactamase (ESBL/AmpC)‐producing E. coli. In addition, 260 broiler and 15 turkey samples were screened for carbapenemase‐producing E. coli. Susceptibility to different class of cephalosporins and meropenem was determined with disc diffusion tests according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Determination of ESBL/AmpC production was performed with a combination disc diffusion test according to the recommendations of the European Food Safety Authority (EFSA). Plasmidic blaESBL/AmpC genes were characterized by polymerase chain reaction and sequencing. A collection of isolates producing AmpC enzyme but not carrying plasmidic blaAmpC was analysed by PCR and sequencing for possible chromosomal ampC promoter area mutations. Altogether ESBL/AmpC‐producing E. coli was recovered from five cattle (0.8%), eight pig (1.5%) and 40 broiler samples (8.1%). No ESBL/AmpC‐producing E. coli was found in turkey samples. Carbapenem resistance was not detected. Altogether ESBL/AmpC‐producing E. coli was found on 4 (2.0%), 3 (4.5%) and 14 (25%) cattle, pig and broiler farms, respectively. From cattle samples 3 (27%) blaCTX‐M‐1 and from broiler samples 13 (33%) blaCTX‐M‐1 and 22 (55%) blaCMY‐2 gene‐carrying isolates were detected. In pigs, no plasmidic blaESBL/AmpC gene‐carrying isolates were found. In all analysed isolates, the same mutations in the promoter region of chromosomal ampC were detected. The results showed low occurrence of ESBL/AmpC‐producing E. coli in Finnish food‐producing animals. In pigs, plasmidic blaESBL/AmpC‐carrying E. coli was not detected at all.  相似文献   
999.
Regression analysis frequently is used to evaluate a new clinical laboratory method. Results from the new method are compared to results from an existing more established method. If measurement error exists in the established method, then least squares may not be an appropriate statistical method to use for the regression analysis. An errors variable regression analysis model was used to evaluate data from five method comparison studies. Results were compared to least squares analyses performed on the same data. When significant measurement error existed in the "reference" method, the errors variable analysis provided a less biased estimate of the regression statistics, which differed markedly from the least squares results. Inappropriate use of least squares in method comparison studies can lead to erroneous conclusions about the relationship of a new analytical method to an existing method.  相似文献   
1000.
肃南县草地退化与治理措施   总被引:1,自引:0,他引:1  
针对肃南县草地退化,草地生产能力下降,植被逆向演变的现实,分析造成草地退化的主要原因是超载过牧、滥垦乱挖、草地利用不合理、气候及虫鼠害等因素所致,提出了治理草地退化的措施。  相似文献   
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