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马铃薯疮痂病菌(Streptomyces spp.)的鉴定 被引量:6
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作者 张建平 刘佳 +4 位作者 哈斯 尹玉和 林团荣 胡冰 张笑宇 《中国马铃薯》 2018年第5期308-314,共7页
由马铃薯疮痂链霉菌(Streptomyces spp.)引致的马铃薯疮痂病是土传兼种传病害,广泛分布世界许多国家,近些年中国发生越来越重。概述了马铃薯疮痂病病原菌有关情况,较详尽地介绍了国内外疮痂链霉菌种的鉴定研究,并提出样本采集要覆盖所... 由马铃薯疮痂链霉菌(Streptomyces spp.)引致的马铃薯疮痂病是土传兼种传病害,广泛分布世界许多国家,近些年中国发生越来越重。概述了马铃薯疮痂病病原菌有关情况,较详尽地介绍了国内外疮痂链霉菌种的鉴定研究,并提出样本采集要覆盖所有研究的马铃薯种植区域的建议,以期为今后的研究提供参考。 展开更多
关键词 马铃薯 疮痂链霉菌 鉴定
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基于改进YOLOv3-SPP算法的道路车辆检测 被引量:2
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作者 王涛 冯浩 +4 位作者 秘蓉新 李林 何振学 傅奕茗 吴姝 《通信学报》 EI CSCD 北大核心 2024年第2期68-78,共11页
针对在城市道路场景下视觉检测车辆时,车辆密集和远处车辆呈现小尺度,导致出现检测精度低或者漏检的问题,提出了一种基于改进的YOLOv3-SPP算法,对激活函数进行优化,以DIOU-NMS Loss作为边界框损失函数,增强网络的表达能力。为提高所提... 针对在城市道路场景下视觉检测车辆时,车辆密集和远处车辆呈现小尺度,导致出现检测精度低或者漏检的问题,提出了一种基于改进的YOLOv3-SPP算法,对激活函数进行优化,以DIOU-NMS Loss作为边界框损失函数,增强网络的表达能力。为提高所提算法对小目标和遮挡目标的特征提取能力,引入空洞卷积模块,增大目标的感受野。实验结果表明,所提算法在检测车辆目标时m AP提高了1.79%,也有效减少了在检测紧密车辆目标时出现的漏检现象。 展开更多
关键词 车辆检测 YOLOv3-spp算法 激活函数 空洞卷积 深度学习
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FOSB、SPP1基因表达对经肝动脉介入化疗栓塞术治疗的中晚期肝癌生存期预测价值
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作者 燕普 蔡瑜 曾建挺 《西部医学》 2024年第7期992-997,共6页
目的探讨骨肉瘤原癌基凶同源物B(FOSB)、分泌性磷蛋白1(SPP 1)基因表达对经肝动脉介入化疗栓塞术治疗的中晚期肝癌患者术后生存期的预测价值。方法回顾性分析2016年1月—2017年10月在西安医学院第一附属医院进行诊治的中晚期肝癌患者11... 目的探讨骨肉瘤原癌基凶同源物B(FOSB)、分泌性磷蛋白1(SPP 1)基因表达对经肝动脉介入化疗栓塞术治疗的中晚期肝癌患者术后生存期的预测价值。方法回顾性分析2016年1月—2017年10月在西安医学院第一附属医院进行诊治的中晚期肝癌患者115例作为研究对象,根据FOSB、SPP 1基因表达水平分为FOSB高表达组(n=52)、FOSB低表达组(n=63)及SPP 1高表达组(n=89)、SPP 1低表达组(n=26)。同时选取115例健康体检者为健康对照组。分析FOSB、SPP 1表达与中晚期肝癌患者临床病理特征的关系。对纳入研究的患者进行为期60个月的随访,Logistics风险回归模型分析影响患者生存期的危险因素。Kaplan-Meier生存曲线分析FOSB、SPP 1表达水平与患者生存预后的关系。结果肝癌患者外周血单个核细胞中FOSB mRNA表达水平明显低于健康对照组,SPP 1 mRNA表达水平明显高于健康对照组,差异具有统计学意义(P<0.05)。FOSB、SPP 1表达在中晚期肝癌患者肿瘤大小、Child-Pugh分级、淋巴转移、BCLC分期方面比较差异具有统计学意义(P<0.05)。单因素分析结果显示,存活组和死亡组在肿瘤大小、Child-Pugh分级、淋巴转移、BCLC分期、FOSB、SPP 1表达方面比较,差异均具有统计学意义(P<0.05)。肿瘤大小、Child-Pugh分级、淋巴转移、BCLC分期、FOSB低表达、SPP 1高表达均为中晚期肝癌患者生存期的独立危险因素(P<0.05)。随访时间60个月,患者生存率为17.39%(20/115),FOSB高表达组中位生存时间为39.7个月,明显高于FOSB低表达组的19.3个月(P<0.05);SPP 1低表达组中位生存时间为40个月,明显高于SPP 1高表达组的18个月(P<0.05)。结论FOSB在中晚期肝癌患者中表达明显下调,SPP 1表达上调,其对预测中晚期肝癌患者肝动脉介入化疗栓塞术治疗生存期具有一定的价值。FOSB、SPP 1有望成为评估介入术治疗患者预后的潜在指标,可协同肿瘤大小、Child-Pugh分级、淋巴转移、BCLC分期等临床指标预测或评估肝癌患者术后生存情况。 展开更多
关键词 FOSB spp 1 经肝动脉介入化疗栓塞术 中晚期肝癌 生存期 预测价值
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SPP1和PD-L1在子宫内膜癌组织中的表达及其预后价值
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作者 胡帅 武霞 +2 位作者 晋雨楠 范裕裕 索玉平 《现代肿瘤医学》 CAS 2024年第21期4121-4126,共6页
目的:分析分泌型磷蛋白1(secreted phosphoprotein 1,SPP1)和程序性死亡蛋白配体1(programmed cell death-ligand 1,PD-L1)在子宫内膜癌(endometrial carcinoma,EC)组织中的表达水平及与预后的关系。方法:通过免疫组织化学方法分析SPP1... 目的:分析分泌型磷蛋白1(secreted phosphoprotein 1,SPP1)和程序性死亡蛋白配体1(programmed cell death-ligand 1,PD-L1)在子宫内膜癌(endometrial carcinoma,EC)组织中的表达水平及与预后的关系。方法:通过免疫组织化学方法分析SPP1和PD-L1在84例EC组织和61例正常子宫内膜组织中的表达情况,分析SPP1和PD-L1表达与临床病理特征及预后的关系,利用UALCAN分析工具(https://ualcan.path.uab.edu/)分析癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库中EC组织SPP1和PD-L1 mRNA的表达及与预后的关系。结果:EC组织SPP1阳性表达率高于正常子宫内膜组织(71.43%vs 36.07%,P=0.001),PD-L1阳性表达率低于正常子宫内膜组织(25.00%vs 42.62%,P=0.025);EC组织中,SPP1阳性表达率与组织学分级相关(P<0.05),PD-L1阳性表达率与淋巴结转移相关(P<0.05),SPP1与PD-L1表达呈正相关(列联系数r=0.237,P=0.026);EC组织中,不同SPP1和PD-L1表达患者总生存期无差异(均P>0.05)。TCGA数据库中生物信息学分析显示EC中SPP1 mRNA表达水平显著高于正常子宫内膜组织(P<0.01),PD-L1 mRNA表达水平与正常子宫内膜组织比较,差异无统计学意义(P=0.057);EC组织SPP1 mRNA和PD-L1 mRNA表达水平呈正相关(r=0.350,P<0.05);不同SPP1和PD-L1表达水平患者总生存期无差异(均P>0.05)。结论:SPP1在EC组织中的表达与PD-L1呈正相关,可能共同参与EC免疫微环境调控,SPP1和PD-L1均不是EC独立预后因子。 展开更多
关键词 spp1 PD-L1 子宫内膜癌 预后
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Genetic Diversity of Jute Mallow (Corchorus spp.) Accessions Based on ISSR Markers
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作者 Munguatosha Ngomuo Tsvetelina Stoilova +1 位作者 Tileye Feyissa Patrick A. Ndakidemi 《American Journal of Plant Sciences》 CAS 2024年第5期316-328,共13页
Jute mallow is a nutritious leafy vegetable. The leaves are rich in proteins, vitamins and essential amino acids. Molecular characterization of Jute mallow with focus on improvement of leaf yield is scarcely reported.... Jute mallow is a nutritious leafy vegetable. The leaves are rich in proteins, vitamins and essential amino acids. Molecular characterization of Jute mallow with focus on improvement of leaf yield is scarcely reported. In the present study, inter sequence simple repeats (ISSR) molecular markers were employed to assess genetic diversity and relationships of 83 accessions of Jute mallow from different parts of Africa and Asia conserved at the World Vegetable Center East and Southern Africa. A total of 89 bands were amplified by 8 ISSR primers. Number of polymorphic bands per primer ranged from 2 to 6 with an average of 2.75 bands per primer. Polymorphic information content (PIC) values ranged from 0.390 to 0.760 with average of 0.53. Average Nei’s gene diversity (h) and Shannon’s information index (I) were 0.335 and 0.494 respectively. The highest pairwise genetic distance was 0.431 observed in a population from East Africa accessions. PC1 and PC2 axis explained 21.69% and 11.66% of the total variation respectively. UPGMA cluster analysis grouped the accessions into six main clusters at genetic similarity coefficient of 0.53 as standard value for classification. These results have important implications for jute mallow breeding and conservation. 展开更多
关键词 Corchorus spp. Genetic Diversity ISSRS Jute Mallow Leafy Vegetable
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Prevalence and Antibiotic Resistance of Urinary Tract Pathogens, with Molecular Identification of Klebsiella pneumoniae, Klebsiella oxytoca, and Acinetobacter spp., Using Multiplex Real-Time PCR
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作者 Hawa Tarnagda Djénéba Ouermi +12 位作者 Tani Sagna Wendyam Marie Christelle Nadembega Abdoul Karim Ouattara Lassina Traoré Rogomenoma Alice Ouedraogo Prosper Bado Bapio Valérie Elvira Jean Télesphore Bazie Nicole Bouda/Zongo Luc Zongo Albert Théophane Yonli Théodora Mahoukèdè Zohoncon Florencia Wendkuuni Djigma Jacques Simpore 《American Journal of Molecular Biology》 CAS 2024年第4期245-260,共16页
Urinary tract infections (UTIs) caused by uropathogens are a significant public health problem, and their treatment primarily relies on antibiotic therapy. However, the increasing global development of antibiotic resi... Urinary tract infections (UTIs) caused by uropathogens are a significant public health problem, and their treatment primarily relies on antibiotic therapy. However, the increasing global development of antibiotic resistance necessitates updating diagnostic techniques to ensure higher sensitivity and specificity, especially with advancements in science and medicine. This study aimed to evaluate the prevalence of UTIs and antibiotic resistance profiles through urine culture, as well as to identify Klebsiella pneumoniae, Klebsiella oxytoca, and Acinetobacter spp. in urine samples using a molecular approach with multiplex real-time PCR. From May 3 to July 25, 2023, at the Pietro Annigoni Biomolecular Research Center (CERBA) and Saint Camille Hospital of Ouagadougou (HOSCO), 209 urine samples collected from patients with suspected UTIs were analyzed using both urine culture and multiplex real-time PCR. Among the 209 patients, 52.15% were male and 47.85% female, with an average age of 46.87 ± 21.33 years. Urine cultures revealed an overall UTI prevalence of 23.44%, with a prevalence of 8.13% in men versus 15.31% in women (P = 0.023). The bacterial prevalence rates were as follows: Escherichia coli (12.92%), Klebsiella spp. (7.18%), Enterobacter cloacae (1.44%), Staphylococcus aureus (0.96%), and other bacteria. Klebsiella spp. demonstrated 100% resistance to Amoxicillin and Amoxicillin/Clavulanic Acid, while Escherichia coli showed 96.2% and 65.4% resistance to Amoxicillin and Amoxicillin/Clavulanic Acid, respectively. PCR analysis of the target bacteria revealed mono-infection prevalence rates of Klebsiella pneumoniae (10.39%), Klebsiella oxytoca (7.79%), and Acinetobacter spp. (7.79%), along with a co-infection prevalence rate of Klebsiella pneumoniae/Acinetobacter spp. (1.30%). This study demonstrated that PCR, with its high sensitivity and specificity, could effectively distinguish Klebsiella pneumoniae from Klebsiella oxytoca and detect Acinetobacter spp. in less than 24 hours—something urine culture alone could not achieve. The relative ease of automating urine PCR testing, combined with its diagnostic accuracy and rapid turnaround time, makes it a valuable addition to modern medical practice for the laboratory diagnosis of UTIs. 展开更多
关键词 Urinary Tract Infections Klebsiella pneumoniae Klebsiella oxytoca Acinetobacter spp. Urine Culture Real-Time PCR
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Effect of dissolved organic nitrogen on the bloom of Prorocentrum donghaiense and Karenia spp. in the East China Sea coastal waters
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作者 Xiaoru Cui Guangming Zhen +2 位作者 Jing Zhao Keqiang Li Xiulin Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期71-85,共15页
Understan ding the mechanism of harmful algal bloom formation is vital for effectively preventing algal bloom outbreaks in coastal environments.Karenia spp.blooms in the East China Sea show a significant correlation w... Understan ding the mechanism of harmful algal bloom formation is vital for effectively preventing algal bloom outbreaks in coastal environments.Karenia spp.blooms in the East China Sea show a significant correlation with nutrient regimes.However,the impact of key components of nutrients,especially dissolved organic nitrogen(DON),on the blooms of Karenia spp.is not clear.Quantitative research is still lacking.In this study,the cruise observations,field mesocosm-flask culture experiments,and a multinitrogen-tri-phytoplankton-detritus model(NTPD) are combined to reveal the quantitative influence of nutrient regimes on the shift of Prorocentrum donghaiense and Karenia spp.in the East China Sea.It has a synchronism rhythm of diatom-P.donghaienseKarenia spp.-diatom loop in the field culture experiment,which is consistent with the results of the cruise observation.The results showed that the processes of terrigenous DON(TeDON) and dissolved inorganic nitrogen(DIN:NO_(3)^(-)-N,NH_(4)^(+)-N) absorption promoted P.donghaiense to become the dominant algae in the community;whereas the processes of DON from P.donghaiense absorption promoted Karenia spp.to become the dominant algae in ambient DIN exhaustion.In addition,the three-dimensional fluorescence components of humus C,tyrosine and fulvic acid can indicate the processes of growth and extinction of P.donghaiense and Karenia spp.,respectively.This study infers that P.donghaiense and Karenia spp.regime shift mechanism associated with the nutrient regime in coastal waters,which provides a scientific basis for the environmental management of coastal eco system health. 展开更多
关键词 Karenia spp. Prorocentrum donghaiense NUTRIENTS multinitrogen-tri-phytoplankton-detritus model three-dimensional fluorescence
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Strawberry (Fragaria spp.): Cultivation, Production, Consumption, and Marketing in Cameroon
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作者 Djeuani Astride Carole Moutamal Djem Rose Theophine Derricka +21 位作者 Mbouobda Hermann Désiré Abdoulaye Souaibou Meliga Essimi Célestine Bouopda Nono Joël Anafack Donasson Dioril Messouang Bernard Didier Ndongo III Boris Charlen Kaffo Emmanuel Kamga Fossouo Anselme Xavier Tiki Antoine Marie Kevin Nyimiebolo Bengono Audrey Maguy Manuela Diobe Motassy Adounga Samuel Brice Amama Amama Benjamin Nshanji Jones Panguepko Fendju Christophe Nzie Oussena Nguetrapouna Issofa Mpon Ikoyin Linda NKouéya Christelle Ladone Amang Amang A. Ziem Niemenak Nicolas 《Agricultural Sciences》 2024年第4期449-471,共23页
Strawberry (Fragaria spp.) is one of the most important fruits classified as exotic fruits imported into Cameroon. To have an inventory of its cultivation in Cameroon, a survey study was carried out among eight farms ... Strawberry (Fragaria spp.) is one of the most important fruits classified as exotic fruits imported into Cameroon. To have an inventory of its cultivation in Cameroon, a survey study was carried out among eight farms of Fragaria spp. from January 2021 to February 2022. The plant was introduced in Cameroon in 2018. There are 13 varieties of Fragaria spp. currently cultivated. Among these 13 varieties, eleven are hybrids of Fragaria x ananassa (“Amiga”, “Amine”, “Camarosa”, “Chandler”, “Charlotte”, “Elsanta”, “Gariguette”, “Madame Moutot”, “Ostara”, “Ruby gem” and “San Andreas”), and two of the hybrids of Fragaria vesca (“Maestro” and “Mara des bois”). The cropping system, irrigation system, and type of fertilizers applied differ from one strawberry farm to another. Biofertilizers (such as mycorrhizal), inorganic and organic fertilizers are actually used to improve production. The potential annual production of strawberries from January 2021 to February 2022, estimated based on the survey data, was 21.216 tons for all growers. Among these eight production farms, the Lolodorf BIO Farm presents 6000 kg (six tons) of strawberries and 100,000 stolons (seedlings) produced, from seven varieties of Fragaria spp. cultivated, with 6 varieties which are hybrids variety Fragaria x ananassa (“Amiga”, “Amine”, “Chandler”, “Gariguette”, “Madame Moutot”, and “Ruby gem”), and one which is a hybrid of Fragaria vesca (“Mara des bois”). Certain diseases were also observed and recorded depending on the growing areas. 展开更多
关键词 Fragaria spp. Cultivation Technique Attack of Pathogens Annual Production Cameroon
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Botulinum toxin type A-targeted SPP1 contributes to neuropathic pain by the activation of microglia pyroptosis
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作者 Li-Ping Chen Xiao-Die Gui +3 位作者 Wen-Di Tian Hou-Ming Kan Jin-Zhao Huang Fu-Hai Ji 《World Journal of Psychiatry》 SCIE 2024年第8期1254-1266,共13页
BACKGROUND Neuropathic pain(NP)is the primary symptom of various neurological condi-tions.Patients with NP often experience mood disorders,particularly depression and anxiety,that can severely affect their normal live... BACKGROUND Neuropathic pain(NP)is the primary symptom of various neurological condi-tions.Patients with NP often experience mood disorders,particularly depression and anxiety,that can severely affect their normal lives.Microglial cells are as-sociated with NP.Excessive inflammatory responses,especially the secretion of large amounts of pro-inflammatory cytokines,ultimately lead to neuroinflam-mation.Microglial pyroptosis is a newly discovered form of inflammatory cell death associated with immune responses and inflammation-related diseases of the central nervous system.METHODS Two models,an in vitro lipopolysaccharide(LPS)-stimulated microglial cell model and a selective nerve injury model using BTX-A and SPP1 knockdown treatments,were used.Key proteins in the pyroptosis signaling pathway,NLRP3-GSDMD,were assessed using western blotting,real-time quantitative polymerase chain reaction,and immunofluorescence.Inflammatory factors[interleukin(IL)-6,IL-1β,and tumor necrosis factor(TNF)-α]were assessed using enzyme-linked immuno-sorbent assay.We also evaluated microglial cell proliferation and apoptosis.Furthermore,we measured pain sensation by assessing the delayed hind paw withdrawal latency using thermal stimulation.RESULTS The expression levels of ACS and GSDMD-N and the mRNA expression of TNF-α,IL-6,and IL-1βwere enhanced in LPS-treated microglia.Furthermore,SPP1 expression was also induced in LPS-treated microglia.Notably,BTX-A inhibited SPP1 mRNA and protein expression in the LPS-treated microglia.Additionally,depletion of SPP1 or BTX-A inhibited cell viability and induced apoptosis in LPS-treated microglia,whereas co-treatment with BTX-A enhanced the effect of SPP1 short hairpin(sh)RNA in LPS-treated microglia.Finally,SPP1 depletion or BTX-A treatment reduced the levels of GSDMD-N,NLPRP3,and ASC and suppressed the production of inflammatory factors.CONCLUSION Notably,BTX-A therapy and SPP1 shRNA enhance microglial proliferation and apoptosis and inhibit microglial death.It improves pain perception and inhibits microglial activation in rats with selective nerve pain. 展开更多
关键词 Botulinum toxin A spp1 MICROGLIA PYROPTOSIS Neuropathic pain
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Multidrug-Resistant of Escherichia coli and Salmonella spp. Strains in Chicken Feces Intended for Consumption in Open Spaces of Ouagadougou, Burkina Faso
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作者 Stéphanie Lynseh Carine Sita Bénao Dabiré Amana Métuor +7 位作者 Abdoul Karim Ouattara Rahimatou Yasmine Wendkouni Tiemtoré Nicolas Ouédraogo Blandine Ouédraogo Rhaina Olivia Badini Lionel Eliada Benoit Bambara Serge Sougué Jacques Simporé 《Open Journal of Applied Sciences》 2024年第4期881-892,共12页
Resistant bacteria can be transmitted to humans through feces or contaminated meat from local chickens. Bacterial strains were isolated from the intestinal contents of 400 local chicken samples from various sales site... Resistant bacteria can be transmitted to humans through feces or contaminated meat from local chickens. Bacterial strains were isolated from the intestinal contents of 400 local chicken samples from various sales sites. These strains were then characterized using bacteriological and biochemical methods to identify resistant strains. In a study conducted in Ouagadougou, we systematically collected chicken fecal samples from 20 locations across the city, followed by isolation and identification of Salmonella spp. using specific enrichment and culture methods, as well as Escherichia coli. Bacterial strains were characterized using antibiotic resistance profiles were determined through agar diffusion tests, revealing sensitivity or resistance to a range of antibiotics based on established scientific criteria. The results showed that out of the 400 samples collected, 81.25% and 63.5% were contaminated by Escherichia coli and Salmonella spp., respectively. Among these, 86.15% of identified Escherichia coli and 50.78% of Salmonella spp. displayed resistance to at least one tested antibiotic. Among 280 Escherichia coli isolates identified resistant to at least one antibiotic, 31.07% were resistant to cefotaxime (CTX), 20.35% to ceftazidime (CAZ), 21.07% to ceftriaxone (CTR), 75% to amoxicillin clavulanic acid (AMC), 23.57% aztreoname (ATM) and 27.14% were resistant to imipenem (IMP). In the case of the 129 Salmonella spp. isolates resistant to at least one tested antibiotic, 34.88% were resistant to CTX;41.08% to CAZ;35.65% to CTR, 92% to AMC, 39.53% to ATM and finally 47.28% were resistant to IMP. Our study revealed high prevalence of resistance in bacterial strains isolated from local chickens sold outdoors in Ouagadougou. These findings raise significant public health concerns, due to the possible transmission of these resistant strains to humans through the consumption of contaminated meat, thus complicating the treatment of bacterial infections. 展开更多
关键词 MULTIDRUG-RESISTANT CHICKEN OUAGADOUGOU Escherichia coli Salmonella spp. Antibiotic
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基于SPPs的二维多凹槽结构MIM波导透射特性的研究
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作者 胡月 陈春梅 孙文汇 《科技与创新》 2024年第9期40-42,共3页
不规则结构对波导的传播特性有着很大的影响,但对于MIM(Metal-Insulator-Metal,金属-介质-金属型)波导双边矩形槽并添加多凹槽结构对传播特性的影响方面的研究尚少。在研究内嵌凹槽位置对MIM波导透射特性影响的基础上,提出了在双矩形波... 不规则结构对波导的传播特性有着很大的影响,但对于MIM(Metal-Insulator-Metal,金属-介质-金属型)波导双边矩形槽并添加多凹槽结构对传播特性的影响方面的研究尚少。在研究内嵌凹槽位置对MIM波导透射特性影响的基础上,提出了在双矩形波导模型基础的内部添加多凹槽结构来影响波导的透射特性,并对波长与透射的关系及不同凹槽位置、不同凹槽数目的电场模图进行了对比分析。在凹槽位置改变时,Fano共振峰位置发生了移动,在小波长区域共振峰的数目也有所改变。随着上凹槽位置的增大,最大透射峰位置发生了蓝移,透射强度也有一定的增强;增加凹槽对数,得到波长与透射特性的关系曲线发生了改变,随着凹槽对数的增加,Fano共振峰的位置发生了一定的红移,且在小波长600~1 000 nm区域,Fano共振峰数目及透射峰值均发生了变化。这些研究结果可为预测金属缝隙波导制备过程中小尺度、多凹槽局部缺陷结构对其传播特性的影响提供理论依据。 展开更多
关键词 sppS 异常透射 MIM波导 透射特性
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差分码偏差产品对BDS-3多频SPP影响分析
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作者 肖明学 《经纬天地》 2024年第5期6-10,15,共6页
为分析不同差分码偏差(differential code bias,DCB)产品对BDS-3多频伪距单点定位(single point positioning,SPP)的影响,基于IGS跟踪站实测数据,对比分析CAS产品、DLR产品、GBM产品解算B1C/B2a、B1I/B3I、B1C/B2a/B3I、B1I/B2a/B3I伪... 为分析不同差分码偏差(differential code bias,DCB)产品对BDS-3多频伪距单点定位(single point positioning,SPP)的影响,基于IGS跟踪站实测数据,对比分析CAS产品、DLR产品、GBM产品解算B1C/B2a、B1I/B3I、B1C/B2a/B3I、B1I/B2a/B3I伪距单点定位精度的影响。试验结果表明:采用CAS产品解算BDS-3双频和三频伪距单点定位精度较优;采用DLR产品解算B1I/B3I和B1I/B2a/B3I伪距单点定位精度较优,但低于CAS产品;采用DLR产品和GBM产品解算B1C/B2a和B1C/B2a/B3I伪距单点定位精度较差,E、N、U 3个方向精度均低于7 m;无论采用哪种产品,三频伪距单点定位精度均优于双频伪距单点定位精度,且提升量较优。 展开更多
关键词 BDS-3 差分码偏差产品 spp
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金枪鱼共附生菌Streptomyces sp.TUN21的次级代谢产物研究
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作者 余磊 《现代畜牧科技》 2024年第7期34-36,共3页
海洋动物共附生微生物次级代谢产物是海洋药物的重要来源。该文从金枪鱼共附生菌Streptomyces sp.TUN21的次级代谢产物中分离得到3个化合物,分别为campechic acid B(1),5-(3’-aminophenyl)-2,4-pentadienoic acid(2)和benzenemethanol... 海洋动物共附生微生物次级代谢产物是海洋药物的重要来源。该文从金枪鱼共附生菌Streptomyces sp.TUN21的次级代谢产物中分离得到3个化合物,分别为campechic acid B(1),5-(3’-aminophenyl)-2,4-pentadienoic acid(2)和benzenemethanol(3)。其中化合物1对PC-3和HCT-116的抑制活性的IC_(50)值分别为(1.3±0.2)μmol和(0.64±0.1)μmol,而化合物2是首次从该属中分离得到的天然产物。化合物1~3在50μg/mL的浓度下对耐甲氧金黄色葡萄球菌、大肠杆菌和白色念珠菌无抑制活性。 展开更多
关键词 金枪鱼共附生菌 streptomyces sp. 抗肿瘤活性 抗微生物活性
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海洋链霉菌Streptomyces sporoverrucosus 33510次级代谢产物研究
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作者 刘颖 肖阳 +10 位作者 朱震鑫 刘洪存 姜明国 朱玉章 林坤 吴金城 卢晓梅 黄小宁 梁海娜 卢文森 杨立芳 《热带海洋学报》 CAS CSCD 北大核心 2024年第2期128-134,共7页
为获得具有较好抑制植物病原菌活性的化合物,对一株海洋链霉菌Streptomyces sporoverrucosus 33510的化学成分及活性进行了研究。使用高效液相色谱(high performance liquid chromatography, HPLC)、半制备液相色谱(semi-pre HPLC)、柱... 为获得具有较好抑制植物病原菌活性的化合物,对一株海洋链霉菌Streptomyces sporoverrucosus 33510的化学成分及活性进行了研究。使用高效液相色谱(high performance liquid chromatography, HPLC)、半制备液相色谱(semi-pre HPLC)、柱色谱(colume chromatography, CC)、薄层色谱(thin layer chromatography, TLC)和重结晶等分析及分离技术对该菌株的发酵产物进行了分离纯化。采用核磁共振(nuclear megnetic resonance,NMR)、质谱(mass spectra,MS)、旋光(optical rotatory dispersion,ORD)等波谱学方法对得到的化合物进行结构鉴定。通过滤纸片法对化合物进行抑菌活性检测。从33510菌株的发酵产物中共分离得到10个化合物,分别为:cyclo(D-Pro-D-Leu)(1)、bisphenol A (2)、methylp-hydroxyphenylacetate (3)、N-phenethylacetamide(4)、3-indole-methylethanoate(5)、dibutyl phthalate(6)、cyclo(D-Pro-L-Leu)(7)、cyclo(D-Pro-L-Ile)(8)、cyclo(L-Pro-L-Phe)(9)和cyclo(L-Leu-L-Val)(10)。除化合物5和9外,其他8个化合物均为首次从该菌种中分离得到。抑菌结果表明,抑菌摩尔浓度为0.19mmol·L-1时,化合物2对板栗疫病菌(Cryphonectria parasitica)的抑制效果为高敏(抑菌直径为20mm)。 展开更多
关键词 海洋链霉菌 次级代谢产物 抑菌活性
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链霉菌Streptomyces sp.P325的化学成分研究
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作者 唐相琴 姜瑞金 +3 位作者 毕晓旭 陈秀 何江波 王莹 《天然产物研究与开发》 CAS CSCD 北大核心 2024年第11期1868-1873,共6页
对Streptomyces sp.P325的化学成分进行研究。采用正相硅胶柱色谱、ODS反相柱色谱、凝胶柱色谱及半制备高效液相色谱等分离技术对Streptomyces sp.P325发酵产物的乙酸乙酯萃取部分进行分离纯化。从中共分离得到6个化合物,通过波谱数据... 对Streptomyces sp.P325的化学成分进行研究。采用正相硅胶柱色谱、ODS反相柱色谱、凝胶柱色谱及半制备高效液相色谱等分离技术对Streptomyces sp.P325发酵产物的乙酸乙酯萃取部分进行分离纯化。从中共分离得到6个化合物,通过波谱数据分析和文献比对鉴定其结构,其中包括2个新化合物:四羟基十八碳二酸I(1)和四羟基十六碳二酸I(2),以及4个已知化合物:iso-frenolicin B(3)、(R)-7-acetyl-3,6-dihydroxy-8-propyl-3,4-dihydronaphthalen-1(2H)-one(4)、对羟基苯甲酸甲酯(5)和isonicotinaldehyde(6)。对分离得到的化合物1~6进行细胞毒活性评价。结果显示,化合物3对HepG2细胞系表现出显著的抑制活性(IC50为13.11μmol/L),对HeLa细胞的抑制活性为中等(IC50为25.04μmol/L)。 展开更多
关键词 链霉菌 化学成分 分离纯化 结构鉴定 细胞毒活性
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SPP1、OLR1在宫颈癌的表达及临床意义
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作者 赵一昕 徐耀辉 《中文科技期刊数据库(引文版)医药卫生》 2024年第7期0194-0198,共5页
观察SPP1(分泌型磷酸蛋白1)、OLR1(氧化低密度脂蛋白受体1)在正常宫颈及宫颈癌中的表达情况,探讨二者与宫颈癌相关临床病理资料及预后的关系。方法 选取2021年01月至2023年01月就诊于包头市肿瘤医院的48例宫颈癌患者为病例组,获取同一... 观察SPP1(分泌型磷酸蛋白1)、OLR1(氧化低密度脂蛋白受体1)在正常宫颈及宫颈癌中的表达情况,探讨二者与宫颈癌相关临床病理资料及预后的关系。方法 选取2021年01月至2023年01月就诊于包头市肿瘤医院的48例宫颈癌患者为病例组,获取同一时间就诊于该院的48例正常宫颈组织为对照组。应用免疫组化法检测SPP1、OLR1在上述两组的表达情况,初步探讨SPP1和OLR1与宫颈癌患者的关系及二者之间的相关性;采用生物信息学分析对比宫颈癌及正常宫颈中SPP1、OLR1的表达,并分析其与宫颈癌患者生存预后的关系。结果 癌组织中SPP1、OLR1阳性表达率高于正常组织(P<0.05);SPP1的表达与癌组织淋巴结转移、分化程度及FIGO具有相关性(P<0.05);OLR1的表达与癌组织淋巴结转移和分化程度具有相关性(P<0.05);在癌组织中,SPP1和OLR1的表达呈正相关(r=0.423,P=0.007)。与SPP1低表达相比,高表达患者的生存率更低(P<0.05);宫颈癌患者的预后不良与SPP1、OLR1的T分期、N分期相关(P<0.05)。结论 宫颈癌组织的发生发展可能与SPP1、OLR1密不可分,检测这两种蛋白对宫颈癌的发生、发展及预后有一定的帮助。 展开更多
关键词 spp1 OLR1 宫颈癌 免疫组化 生物信息学分析
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Biosorption of Cd (Ⅱ) and Pb (Ⅱ) Ions by Aqueous Solutions of Novel Alkalophillic Streptomyces VITSVK5 spp. Biomass 被引量:6
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作者 Kumar Saurav Krishnan Kannabiran 《Journal of Ocean University of China》 SCIE CAS 2011年第1期61-66,共6页
Discharge of heavy metals from metal processing industries is known to have adverse effects on the environment.Bio-sorption of heavy metals by metabolically inactive biomass of microbial organisms is an innovative and... Discharge of heavy metals from metal processing industries is known to have adverse effects on the environment.Bio-sorption of heavy metals by metabolically inactive biomass of microbial organisms is an innovative and alternative technology for removal of these pollutants from aqueous solution.The search of marine actinobacteria with potential heavy metal biosorption ability resulted in the identification of a novel alkalophilic Streptomyces VITSVK5 species.The biosorption property of Streptomyces VITSVK5 spp.was investigated by absorbing heavy metals Cadmium (Cd) and Lead (Pb).Physiochemical characteristics and trace metal concentration analysis of the backwater showed the concentrations of different metals were lead 13±2.1 μg L-1,cadmium 3.1±0.3μg L-1,zinc 8.4±2.6μg L-1 and copper 0.3±0.1μg L-1,whereas mercury was well below the detection limit.The effect of pH and biomass dosage on removal efficiency of heavy metal ions was also investigated.The optimum pH for maximal biosorption was 4.0 for Cd (II) and 5.0 for Pb (II) with 41% and 84% biosorption respectively.The biosorbent dosage was optimized as 3 g L-1 for both the trace metals.Fourier transform infrared absorption spectrum results indicated the chemical interactions of hydrogen atoms in carboxyl (–COOH),hydroxyl (–CHOH) and amine (–NH2) groups of biomass with the metal ions.This could be mainly involved in the biosorption of Cd (II) and Pb (II) onto Streptomyces VITSVK5 spp.The results of our study revealed Streptomyces metabolites could be used to develop a biosorbent for adsorbing metal ions from aqueous environments. 展开更多
关键词 heavy metals BIOSORPTION streptomyces VITSVK5 spp pH biomass dosage
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智能手机BDS-3/GPS数据质量及SPP性能分析 被引量:2
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作者 王瑞光 王中元 +2 位作者 胡超 王阳阳 刘冰雨 《大地测量与地球动力学》 CSCD 北大核心 2023年第2期168-172,共5页
使用可观测到BDS-3 B1I/B1C/B2a频率和GPS L1/L5频率的智能手机Xiaomi 11(青春版)作为研究对象,分别进行静态实验和不同场地的动态实验,分析手机输出的三频BDS和双频GPS原始观测数据质量及单频SPP性能。实验结果表明,智能手机的GNSS天... 使用可观测到BDS-3 B1I/B1C/B2a频率和GPS L1/L5频率的智能手机Xiaomi 11(青春版)作为研究对象,分别进行静态实验和不同场地的动态实验,分析手机输出的三频BDS和双频GPS原始观测数据质量及单频SPP性能。实验结果表明,智能手机的GNSS天线成本低致使其信号质量不佳,其中GPS L1频率和BDS B1C频率抗干扰性较强:BDS B1C频率定位结果在静态和动态实验中均较为稳定;GPS L1频率定位结果在动态实验中优于GPS L5频率,在静态实验中略差于GPS L5频率。 展开更多
关键词 Android智能手机 单频spp BDS-3 GPS 数据质量分析
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鸭SPP1基因的生物信息学分析、原核表达及其在鸭胚胎期骨骼肌中表达规律研究 被引量:1
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作者 曹敞 职卓 +6 位作者 蔡瑛婕 李雨笑 张纪桥 张淑雅 刘小林 胡志刚 张建勤 《中国畜牧杂志》 CAS CSCD 北大核心 2023年第7期147-154,共8页
分泌型焦磷酸蛋白1(SPP1)是一种具有多种功能的分泌型酸性糖蛋白,在肌肉发育过程中具有重要的调控作用,但SPP1基因在鸭骨骼肌中的结构和功能尚不明确。本研究选择胚胎期第17天(E17 d)、第21天(E21 d)、第24(E24 d)和第27天(E27 d)北京... 分泌型焦磷酸蛋白1(SPP1)是一种具有多种功能的分泌型酸性糖蛋白,在肌肉发育过程中具有重要的调控作用,但SPP1基因在鸭骨骼肌中的结构和功能尚不明确。本研究选择胚胎期第17天(E17 d)、第21天(E21 d)、第24(E24 d)和第27天(E27 d)北京鸭和汉中麻鸭胸肌及腿肌组织作为实验材料,克隆了SPP1基因的CDS区序列并对该序列进行分析,进一步诱导基因表达,采用SDS-PAGE检测表达蛋白。同时采用qPCR方法分析SPP1基因在胚胎期北京鸭与汉中麻鸭胸肌和腿肌组织中的相对表达。结果表明:SPP1基因开放阅读框大小为915 bp,编码304个氨基酸,是有SP型信号肽的亲水性不稳定蛋白,无跨膜结构,有磷酸化和糖基化位点。qPCR结果表明,北京鸭骨骼肌SPP1的表达量在E27 d达到最高;而汉中麻鸭胸肌SPP1在E17 d的表达量最高,在E21 d的腿肌中表达量最高。在胚胎期北京鸭与汉中麻鸭骨骼肌的比较中,汉中麻鸭胸肌SPP1基因在E17 d时的表达量显著高于北京鸭,而在E27 d则低于北京鸭。北京鸭腿肌SPP1在E17 d和E27 d的表达量均高于汉中麻鸭,而在E21 d和E24 d则均低于汉中麻鸭。本研究揭示了鸭SPP1基因的结构及该基因在北京鸭和汉中麻鸭骨骼肌中的表达规律,为鸭生长发育的调控机制研究提供一定的参考。 展开更多
关键词 spp1 骨骼肌 原核表达 生物信息学分析 表达规律
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基于YOLOv3-SPP的遥感图像目标检测压缩模型 被引量:2
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作者 齐保贵 赵鹏赫 +2 位作者 陈禾 陈亮 龙腾 《信号处理》 CSCD 北大核心 2023年第9期1621-1632,共12页
近年来,卷积神经网络模型已被广泛应用于遥感图像目标检测任务中,但自然场景图像与遥感图像的目标特性存在差异,针对自然场景设计的模型往往难以在遥感图像任务中取得良好的效果。同时,很多遥感图像处理任务需要在星载、机载等资源有限... 近年来,卷积神经网络模型已被广泛应用于遥感图像目标检测任务中,但自然场景图像与遥感图像的目标特性存在差异,针对自然场景设计的模型往往难以在遥感图像任务中取得良好的效果。同时,很多遥感图像处理任务需要在星载、机载等资源有限的平台中进行,难以部署参数量、计算量大的复杂模型。针对以上问题,本文对在自然场景中性能优异的YOLOv3-SPP模型进行适应性改进及参数压缩。首先,对原始的L1范数剪枝算法进行改进,提出基于L1范数和均值差的加权剪枝算法,能够更好地保留重要的通道。其次,对剪枝后的子网集合进行快速评估,选取评估结果最好的子网进行微调。在预训练和微调阶段,本文将SPP模块中的最大池化层替换为softmax加权池化层,着重突出深层网络中权重较大的特征,提高了模型的检测精度。本文在多个公开遥感数据集上进行实验,结果表明改进的YOLOv3-SPP模型在遥感目标检测任务上具有更好的性能,同时本文的剪枝算法可以在相同的参数压缩比例条件下,降低模型的性能损失。 展开更多
关键词 目标检测 YOLOv3-spp 遥感 模型压缩
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