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Isolated Systolic Hypertension in Geriatrics
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作者 Soumya Erri Terry Oroszi 《International Journal of Clinical Medicine》 2025年第1期29-53,共25页
Hypertension, often called the “silent killer”, is a major risk factor for heart attacks and strokes in the elderly. Its effective management is crucial to prevent damage to the heart, brain, and kidneys. Isolated s... Hypertension, often called the “silent killer”, is a major risk factor for heart attacks and strokes in the elderly. Its effective management is crucial to prevent damage to the heart, brain, and kidneys. Isolated systolic hypertension (ISH) is particularly critical in the elderly population. Cardiovascular risk factors, including pulse pressure and wave velocity, are closely associated with systolic blood pressure and influenced by arterial stiffness and wave reflections. Managing ISH is complex due to the potential negative effects of certain medications and individual variability in treatment response. This paper will address these issues, evaluating antihypertensive drugs, combination therapy, personalized treatment plans, and updated guidelines for managing ISH. 展开更多
关键词 HYPERTENSION Geriatric or Elderly or Adults Types of Hypertension Tests First-Line Treatment DRUGS isolated Systolic Hypertension Other Diseases
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Trends and emerging techniques in isolated power converters
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作者 Lin Cheng Dongfang Pan 《Journal of Semiconductors》 2025年第7期6-9,共4页
Isolated power converters have emerged as an active research topic in power integrated circuit(IC)design.Reflecting this growing interest,ISSCC 2025 has featured a dedicated session on"Isolated Power and Gate Dri... Isolated power converters have emerged as an active research topic in power integrated circuit(IC)design.Reflecting this growing interest,ISSCC 2025 has featured a dedicated session on"Isolated Power and Gate Drivers".These converters enable safe and reliable power delivery across voltage domains and are widely used in renewable energy,electric vehicles,and telecommunications.Galvanic isolation prevents surge currents and ground loop issues in harsh high-voltage environments.As demand grows for compact,efficient,and high–power-density solutions,fully integrated architectures featuring on-chip transformers are increasingly favored over traditional module-based designs,offering>5 kV isolation with a smaller footprint and lower system cost[1]. 展开更多
关键词 ISSCC ground loop issues isolated power converters power integrated circuit galvanic isolation emerging techniques surge currents renewable energyelectric
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Role of varicocelectomy in infertile patients with clinical varicocele and isolated sperm defects
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作者 Mohamed M.Arafa Ahmad A.Majzoub +6 位作者 Walid A.El Ansari Ahmad H.AlMalki Mohammed Y.Mahdi Kareim M.Khalafalla Khalid J.AlKubaisi Sami S.AlSaid Haitham T.ElBardisi 《Asian Journal of Urology》 2025年第2期267-274,共8页
Objective:This study investigated the outcomes of microsurgical subinguinal varicocelectomy(MSV)on semen and hormonal parameters in cases with isolated sperm defects(oligozoospermia,asthenozoospermia,or teratozoosperm... Objective:This study investigated the outcomes of microsurgical subinguinal varicocelectomy(MSV)on semen and hormonal parameters in cases with isolated sperm defects(oligozoospermia,asthenozoospermia,or teratozoospermia).Methods:A retrospective review of charts of patients who underwent MSV for clinically palpable varicocele between January 1,2011 and January 1,2019 at Hamad Medical Corporation was undertaken.All patients diagnosed with isolated oligozoospermia,asthenozoospermia,or teratozoospermia in the preoperative semen analysis were included.Men with multiple sperm defects,genetic abnormalities,azoospermia,history of genitourinary infection,exposure to chemotherapy or radiotherapy,or prior use of peri-operative fertility treatment were excluded.Data extracted from the electronic medical records included(collected before MSV and up to 6 months postoperatively):demographics(age),clinical data(fertility-related medical history and surgical interventions),family history(consanguinity and infertility),physical examination findings from general and local genital exam(varicocele side and grade),laboratory data such as semen analysis,sperm DNA fragmentation tests,and hormone levels(follicle-stimulating hormone,luteinizing hormone,total testosterone,estradiol,and prolactin),and imaging(scrotal color Doppler ultrasound).Results:A total of 331 patients with isolated sperm defects were included.Postoperatively,83.3%of patients showed an improvement in sperm concentration with a median increase of 7 millions/mL.Postoperatively,76.7%of isolated asthenozoospermic patients showed an improvement in total motility and 66.0%had an improvement in progressive motility with median increases of 15.0%and 7.5%,respectively.Postoperatively,70.0%of the teratozoospermic patients showed an improvement in normal sperm morphology with a median increase of 6%.No changes were observed in other semen or hormone parameters that were examined.Conclusion:MSV is a valid and effective treatment modality for patients with isolated sperm defects that significantly corrects their respective semen abnormality and improves their chances of natural conception. 展开更多
关键词 VARICOCELECTOMY isolateD OLIGOZOOSPERMIA ASTHENOZOOSPERMIA TERATOZOOSPERMIA Fertility
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Influence of isolated footing embedment on the seismic performance of building considering the soil-foundation-structure interaction:An experimental approach
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作者 Vaibhav Mittal Manojit Samanta D.P.Kanungo 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期1194-1212,共19页
The present study investigates the influence of embedment depth of isolated footing supporting moment-resisting frame buildings through scaled-down tests.These experiments utilize scaled models representing different ... The present study investigates the influence of embedment depth of isolated footing supporting moment-resisting frame buildings through scaled-down tests.These experiments utilize scaled models representing different building aspect ratios and footing embedment depths.All the model tests are subjected to scaled-down input ground motions of different intensities and magnitudes.These model tests are performed in laminar shear containers through shake table testing.The results obtained for different cases of soil-foundation-structure systems and fixed-base conditions are expressed in terms of natural frequency,peak spectral acceleration,frequency response,lateral deformation,inter-storey drifts,and rocking of the foundation.The analysis reveals that the natural frequency of the coupled system on isolated footings diminishes by 27.52%–58.21%relative to fixed-base conditions,highlighting the significance of accounting for soil-foundation-structure interaction effects.Moreover,a notable increase of 52.97%in the natural frequency of the coupled system is observed as the embedment depth of the footing increases from 0.75 to 6.Additionally,the study demonstrates that the inter-storey drift of the 5-storey building remains well within acceptable limits under dense soil conditions.Consequently,within the parameter range explored in this research,the study concludes that soil-foundation-structure interaction effects are insignificant for low-rise buildings(H≤15 m)supported on isolated footings during seismic events. 展开更多
关键词 Shake table test isolated footing Soil-foundation-structure interaction Laminar shear box EARTHQUAKE
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Multi-objective optimal design of asymmetric base-isolated structures using NSGA-Ⅱ algorithm for improving torsional resistance
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作者 Zhang Jiayu Qi Ai Yang Mianyue 《Earthquake Engineering and Engineering Vibration》 2025年第3期811-825,共15页
Finding an optimal isolator arrangement for asymmetric structures using traditional conceptual design methods that can significantly minimize torsional response while ensuring efficient horizontal seismic isolation is... Finding an optimal isolator arrangement for asymmetric structures using traditional conceptual design methods that can significantly minimize torsional response while ensuring efficient horizontal seismic isolation is cumbersome and inefficient.Thus,this work develops a multi-objective optimization method to enhance the torsional resistance of asymmetric base-isolated structures.The primary objective is to simultaneously minimize the interstory rotation of the superstructure,the rotation of the isolation layer,and the interstory displacement of the superstructure without exceeding the isolator displacement limits.A fast non-dominated sorting genetic algorithm(NSGA-Ⅱ)is employed to satisfy this optimization objective.Subsequently,the isolator arrangement,encompassing both positions and categories,is optimized according to this multi-objective optimization method.Additionally,an optimization design platform is developed to streamline the design operation.This platform integrates the input of optimization parameters,the output of optimization results,the finite element analysis,and the multi-objective optimization method proposed herein.Finally,the application of this multi-objective optimization method and its associated platform are demonstrated on two asymmetric base-isolated structures of varying heights and plan configurations.The results indicate that the optimal isolator arrangement derived from the optimization method can further improve the control over the lateral and torsional responses of asymmetric base-isolated structures compared to conventional conceptual design methods.Notably,the interstory rotation of the optimal base-isolated structure is significantly reduced,constituting only approximately 33.7%of that observed in the original base-isolated structure.The proposed platform facilitates the automatic generation of the optimal design scheme for the isolators of asymmetric base-isolated structures,offering valuable insights and guidance for the burgeoning field of intelligent civil engineering design. 展开更多
关键词 asymmetric base-isolated structures isolator arrangement multi-objective optimization NSGA-Ⅱalgorithm optimization design platform
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Establishment of goat infection model of the peste des petits ruminants virus isolated in China for vaccine efficacy evaluation
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作者 Xue Wang Hefeng Chen +14 位作者 Xianfeng Zhang Zhengshuang Wu Shuai Zhang Lei Shuai Lulu Wang Weijie Li Jinliang Wang Wenxing Liu Xijun Wang Zhiyuan Wen Jinying Ge Yuntao Guan Xijun He Weiye Chen Zhigao Bu 《Journal of Integrative Agriculture》 2025年第8期3199-3211,共13页
In 2013,peste des petits ruminants(PPR)re-emerged in China and spread to the majority of provinces across the country.The disease was effectively controlled through a vaccination campaign employing live attenuated vac... In 2013,peste des petits ruminants(PPR)re-emerged in China and spread to the majority of provinces across the country.The disease was effectively controlled through a vaccination campaign employing live attenuated vaccines,although sporadic cases still occurred.However,limited information is currently available regarding the peste des petits ruminants virus(PPRV)endemic in China.Here,a PPRV strain(HLJ/13)was isolated from a field sample in China using Vero cells expressing goat signalling lymphocyte activation molecule.Phylogenetic analysis indicated that HLJ/13 belonged to lineage IV.Subsequent intranasal and subcutaneous inoculation of goats with a dose of 2×10~6 TCID50of HLJ/13 resulted in the development of typical clinical symptoms of PPR,including pyrexia,ocular and nasal discharges,stomatitis,and diarrhea.All infected goats succumbed to the disease by day 8.To gain further insight,viral loading,pathological examination and immunohistochemical analyses were conducted,elucidating the main targets of HLJ/13 as the respiratory system,digestive tract and lymphoid organs.Employing the goat infection model established above,the goat poxvirus-vectored PPR vaccine,which was previously developed and could be used as DIVA(differentiating infected from vaccinated animals)vaccine,provided complete protection against the challenge of HLJ/13.It is important to note that this study represents the first comprehensive report delineating the biology and pathogenicity characterization,and infection model of PPRV isolated in China. 展开更多
关键词 peste des petits ruminants virus Chinese isolate goat infection model vaccine efficacy evaluation
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Effectiveness of biologics for endoscopic healing in patients with isolated proximal small bowel Crohn’s disease
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作者 Zi-Cheng Huang Bi-Yao Wang +8 位作者 Bo Peng Zhong-Cheng Liu Hui-Xian Lin Qing-Fan Yang Jian Tang Kang Chao Miao Li Xiang Gao Qin Guo 《World Journal of Gastroenterology》 2025年第7期39-50,共12页
BACKGROUND Endoscopic healing(EH)is a key therapeutic target in Crohn’s disease(CD).Proximal small bowel(SB)lesions in patients with CD are associated with a significant risk of strictures and bowel resection.Assessi... BACKGROUND Endoscopic healing(EH)is a key therapeutic target in Crohn’s disease(CD).Proximal small bowel(SB)lesions in patients with CD are associated with a significant risk of strictures and bowel resection.Assessing SB in patients with CD is necessary because of its significant therapeutic implications.The advent of biologic therapies,including infliximab,ustekinumab,and vedolizumab,has significantly altered CD treatment.However,data on the efficacy of biologics in achieving EH,specifically in the proximal SB of patients with CD,remain limited.AIM To assess the effectiveness of biologics for EH in patients with jejunal and/or proximal ileal CD.METHODS Between 2017 and 2023,we retrospectively included 110 consecutive patients with isolated proximal SB CD,identified through baseline balloon-assisted enteroscopy.These patients completed 1-year of treatment with infliximab,ustekinumab,or vedolizumab,and underwent a second balloon-assisted enteroscopy at 1 year.Complete EH was defined as a modified Simple Endoscopic Score for CD(SES-CD)of<3,while EH of the jejunum and proximal ileum was defined as a segmental modified SES-CD of 0.RESULTS In total,64 patients were treated with infliximab,28 with ustekinumab,and 18 with vedolizumab.The complete EH rate at 1 year was 20.9%(23/110),with 29.6%(19/64)for infliximab,10.7%(3/28)for ustekinumab,and 5.5%(1/18)for vedolizumab.The median modified SES-CD significantly decreased compared to baseline[5(2-8)vs 8(6-9),P<0.001].The jejunal and proximal ileal EH rates at 1 year were 30.8%(12/39)and 15.5%(16/103),respectively.Multiple logistic regression analysis showed that stricturing or penetrating disease[odds ratio(OR)=0.261,95%CI:0.087-0.778,P=0.016],prior exposure to biologics(OR=0.080,95%CI:0.010-0.674,P=0.020),and moderate-tosevere endoscopic disease(OR=0.277,95%CI:0.093-0.829,P=0.022)were associated with a lower likelihood of achieving EH at 1 year.CONCLUSION Only 20.9%of patients with isolated proximal SB CD achieved complete EH after 1 year of biologic therapy. 展开更多
关键词 Crohn’s disease isolated proximal small bowel disease Endoscopic healing BIOLOGICS Balloon-assisted enteroscopy
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Sequence stratigraphy analysis and lithofacies paleogeography reconstruction of isolated platform in a rift lake basin:Implications for deepwater hydrocarbon exploration in the subsalt of Santos Basin,Brazil
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作者 HUANG Jixin WANG Hongjun +7 位作者 XU Fang YANG Mengying ZHAO Junfeng LI Peijia LI Chenqing LIU Zeqiang XIONG Ying TAN Xiucheng 《Petroleum Exploration and Development》 2025年第4期982-1000,共19页
By integrating core observations,logging data and seismic interpretation,this study takes the massive Cretaceous carbonates in the M block of the Santos Basin,Brazil,as an example to establish the sequence filling pat... By integrating core observations,logging data and seismic interpretation,this study takes the massive Cretaceous carbonates in the M block of the Santos Basin,Brazil,as an example to establish the sequence filling pattern of fault-bounded isolated platforms in rift lake basins,reveal the control mechanisms of shoal-body development and reservoir formation,and reconstruct the evolutionary history of lithofacies paleogeography.The following results are obtained.(1)Three tertiary sequences(SQ1-SQ3)are identified in the Lower Cretaceous Itapema-Barra Velha of the M block.During the depositional period of SQ1,the rift basement faults controlled the stratigraphic distribution pattern of thick on both sides and thin in the middle.The strata overlapped to uplift in the early stage.During the depositional period of SQ2-SQ3,the synsedimentary faults controlled the paleogeomorphic reworking process with subsidence in the northwest and uplifting in the northeast,accompanied with the relative fall of lake level.(2)The Lower Cretaceous in the M block was deposited in a littoral-shallow lake,with the lithofacies paleogeographic pattern transiting from the inner clastic shoals and outer shelly shoals in SQ1 to the alternation of mounds and shoals in SQ2-SQ3.(3)Under the joint control of relative lake-level fluctuation,synsedimentary faults and volcanic activity,the shelly shoals in SQ1 tend to accumulated vertically in the raised area,and the mound-shoal complex in SQ2-SQ3 tends to migrate laterally towards the slope-break belt due to the reduction of accommodation space.(4)The evolution pattern of high-energy mounds and shoals,which were vertically accumulated in the early stage and laterally migrated in the later stage,controlled the transformation of high-quality reservoirs from“centralized”to“ring shaped”distribution.The research findings clarify the sedimentary patterns of mounds and shoals and the distribution of favorable reservoirs in the fault-controlled lacustrine isolated platform,providing support for the deepwater hydrocarbon exploration in the subsalt carbonate rocks in the Santos Basin. 展开更多
关键词 lacustrine carbonate fault-bounded isolated platform sedimentary pattern sequence lithofacies paleogeography Cretaceous Itapema-Barra Velha Santos Basin
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Environmentally Friendly Tannic Acid-Furfuryl Alcohol-Soybean Isolate/Casein Composite Foams Reinforced with Wood Fibers
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作者 Jinxing Li Mustafa Zor +3 位作者 Xiaojian Zhou Guanben Du Denis Rodrigue Xiaodong(Alice)Wang 《Journal of Renewable Materials》 2025年第2期329-347,共19页
In this study,two series of foams based on tannic acid(TA),furfuryl alcohol(FA),soybean protein isolate(SPI),and casein(CA),namely TA–FA–SPI(TS series)and TA–FA–CA(TC series)were developed,and their properties wer... In this study,two series of foams based on tannic acid(TA),furfuryl alcohol(FA),soybean protein isolate(SPI),and casein(CA),namely TA–FA–SPI(TS series)and TA–FA–CA(TC series)were developed,and their properties were enhanced by adding poplar fibers(WF).From the samples produced,a complete set of characterization was performed including possible crosslinking reactions,morphology,mechanical properties,flame retardancy,thermal insulation and thermal stability.Fourier-transform infrared spectroscopy(FTIR)revealed possible covalent crosslinking among the components and hydrogen bonding between WF and the matrix.Viscosity results indicated that lower prepolymer viscosity led to lower apparent density,while WF addition reduced even more the density.Mechanical tests showed that the maximum compressive strengths were good,while WF improved the compressive strength by up to 56%.Scanning electron microscopy(SEM)showed uniform cell structures,but small open pores were observed.Two-dimensional(2D)CT scan images confirmed the good compatibility between WF and the matrix,with low anisotropy in the material.Friability tests indicated that WF decreased the pulverization ratio of the materials by up to 42%.Thermogravimetric analysis(TGA)showed good thermal stability of the materials up to 328°C.Vertical burning tests showed that the materials were self-extinguishing without residue(dripping).The lowest thermal conductivity was 0.04 W/m·K.These results suggest that these novel formaldehyde-free,high biomass content(95%–96%)foams and composite foams have high potential to replace traditional phenolic foams(PF)in applications such as construction,transportation,packaging,and thermal insulation. 展开更多
关键词 Foam composite tannic acid soybean isolate protein CASEIN poplar fiber compressive strength flame retardancy thermal insulation
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Comparative analysis between genotypes of adenovirus isolates from hospitalized children with acute respiratory tract infections and clinical manifestations in Wuhan,China,from June 2022 to September 2023
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作者 Chunchen Wu Yanfang Zhang +9 位作者 Ao Liang Xiaoxue Wu Yaqi Zhu Zhaoxuan Huang Jun Wang Yali Deng Lixian Pan Anbang Wang Fei Deng Jianbo Xia 《Virologica Sinica》 2025年第1期50-60,共11页
Acute respiratory tract infections(ARTIs)are among the leading causes of morbidity and mortality in children worldwide.Human adenovirus(HAdV)infections are estimated to account for at least 5%of pediatric ARTIs.The ci... Acute respiratory tract infections(ARTIs)are among the leading causes of morbidity and mortality in children worldwide.Human adenovirus(HAdV)infections are estimated to account for at least 5%of pediatric ARTIs.The circulated genotypes of HAdV and the correlation between genotype and clinical manifestations in Wuhan,China,before and after the complete relaxation of nonpharmaceutical interventions against severe acute respiratory syndrome coronavirus 2,remain unknown.Here,101 HAdV strains were isolated from throat swab samples collected from hospitalized children with ARTIs who tested positive for HAdV nucleic acid.Of these,sixty-six strains from 2022 to twenty-three strains from 2023 were successfully genotyped and subjected to phylogenetic analysis based on the hexon,penton base,and fiber genes.Six genotypes,B3,C1,C2,C5,C104,and C108 were identified.HAdV-B3(84.85%)was the most prevalent type in 2022,while HAdV-C(86.96%),including C1,C2,C108,and C104,was the most prevalent in 2023.These strains were phylogenetically related to strains from Japan,China,and the United States in recent years.When comparing clinical characteristics,pediatric patients infected with B3,C1,C2,C5,C104,or C108 exhibited similar clinical manifestations,primarily fever and cough,but varying interleukin(IL)-10 levels.In conclusion,from June 2022 to September 2023,the circulated genotypes of HAdV in Wuhan included B3,C1,C2,C108,C5,and C104.The endemic pattern of HAdV in Wuhan,China,shifted from species B as the dominant type in 2022 to species C in 2023. 展开更多
关键词 Acute respiratory tract infection (ARTIs) Human adenovirus(HAdV) Viral isolates GENOTYPES Clinical characteristics PNEUMONIA
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Transcatheter aortic valve replacement for older patients with isolated aortic regurgitation
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作者 JoséC González Ignacio J.Amat 《Journal of Geriatric Cardiology》 2025年第7期611-614,共4页
Aortic regurgitation(AR)poses distinct challenges in interventional cardiology,necessitating novel approaches for treatment.This editorial examined the evolving landscape of transcatheter aortic valve replacement(TAVR... Aortic regurgitation(AR)poses distinct challenges in interventional cardiology,necessitating novel approaches for treatment.This editorial examined the evolving landscape of transcatheter aortic valve replacement(TAVR)as an alternative therapeutic strategy for AR,particularly in patients deemed high risk for surgery.We explored the anatomical and patho-physiological disparities between AR and aortic stenosis(AS)and elucidates the technical nuances of TAVR procedures in AR pa-tients,emphasizing the need for precise prosthesis positioning and considerations for excessive stroke volume.Additionally,we discussed the safety and efficacy of TAVR compared to SAVR in AR management,drawing insights from recent case series and registry data.Notably,dedicated TAVR devices tailored for AR,such as the J-Valve and JenaValve,demonstrate promising out-comes in reducing residual AR and ensuring procedural success.Conversely,“off-label”TAVR devices,including balloon-ex-pandable and self-expandable platforms,offer feasible alternatives-particularly for large aortic annuli-with favorable device suc-cess rates and low residual AR rates.We highlighted the need for further research,including randomized trials,to delineate the definitive role of TAVR in AR treatment and to address remaining questions regarding device selection and long-term outcomes.In conclusion,TAVR emerges as a viable option for patients with AR,particularly those facing high surgical risks or frailty,with ongoing investigations poised to refine its position in the therapeutic armamentarium. 展开更多
关键词 aortic regurgitation ar poses prosthesis positioning therapeutic strategy isolated aortic regurgitation transcatheter aortic valve replacement transcatheter aortic valve replacement tavr technical nuances residual aortic regurgitation
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云南地区血清7型猪胸膜肺炎放线杆菌的分离鉴定及生物学特性分析
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作者 李富祥 宋建领 李占鸿 《中国畜牧兽医》 北大核心 2026年第1期499-508,共10页
【目的】研究云南地区猪源胸膜肺炎放线杆菌的生物学特性。【方法】从云南红河州某猪场患呼吸道疾病猪肺脏中分离细菌,采用生化试验、16S rDNA序列分析和PCR扩增鉴定分离菌,并分析分离菌的血清型、致病性、药物敏感性和耐药基因等生物... 【目的】研究云南地区猪源胸膜肺炎放线杆菌的生物学特性。【方法】从云南红河州某猪场患呼吸道疾病猪肺脏中分离细菌,采用生化试验、16S rDNA序列分析和PCR扩增鉴定分离菌,并分析分离菌的血清型、致病性、药物敏感性和耐药基因等生物学特性。【结果】从病猪肺脏样品中分离到1株革兰阴性小球杆菌,将其编号为YN240724。生化鉴定结果显示,分离菌分解葡萄糖、果糖、蔗糖、木糖和甘露醇产酸,氧化酶、尿素酶及硝酸盐还原试验呈阳性,其生化特性与胸膜肺炎放线杆菌(Actinobacillus pleuropneumoniae)参考株相同。16S rDNA基因序列分析结果显示,分离菌与胸膜肺炎放线杆菌模式菌株ATCC 27088T和其他胸膜肺炎放线杆菌参考株间的16S rDNA序列相似性分别为100%和99.6%~100%;分离菌株与全部胸膜肺炎放线杆菌参考株形成同一个进化分支;基于上述特征分离菌YN24074被鉴定为胸膜肺炎放线杆菌。血清型鉴定结果显示,该分离菌为胸膜肺炎放线杆菌血清7型。耐药基因检测结果显示,分离菌携带β-内酰胺内耐药基因blaCIT和blaTEM以及四环素类耐药基因tetM。药敏试验结果显示,分离菌对氨基糖苷类(庆大霉素和阿米卡星)、喹诺酮类(氧氟沙星)、酰胺醇类(氟苯尼考)、四环素类(四环素)、磺胺类(磺胺甲噁唑)以及头孢类(头孢噻肟和头孢呋辛)敏感,对青霉素类(青霉素、氨苄西林和哌拉西林)以及糖肽类(万古霉素)耐药。致病性试验结果显示,分离菌对小鼠的半数致死量(LD_(50))为7.5×10^(4)CFU,致病性较强。【结论】本研究从云南地区分离获得1株猪源血清7型胸膜肺炎放线杆菌,其携带耐药基因blaCIT、blaTEM及tetM,对多种抗菌药物表现耐药,致病性较强。试验结果可为云南地区猪场猪传染性胸膜肺炎的治疗和免疫防控提供重要参考。 展开更多
关键词 胸膜肺炎放线杆菌 分离鉴定 血清型 致病性
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广深地区3种常见猫病毒的分离鉴定及遗传进化分析
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作者 孙媛 梁爽爽 +2 位作者 罗志莹 王婷 马静云 《华南农业大学学报》 北大核心 2026年第1期11-20,共10页
【目的】猫杯状病毒(Feline calicivirus,FCV)、猫细小病毒(Feline parvovirus,FPV)和猫疱疹病毒1型(Feline herpesvirus-1,FHV-1)是常见的高传染性、高致病性病原体,本文针对广深地区的这3种病毒开展研究,以期明确本地FCV、FPV和FHV-1... 【目的】猫杯状病毒(Feline calicivirus,FCV)、猫细小病毒(Feline parvovirus,FPV)和猫疱疹病毒1型(Feline herpesvirus-1,FHV-1)是常见的高传染性、高致病性病原体,本文针对广深地区的这3种病毒开展研究,以期明确本地FCV、FPV和FHV-1的流行情况、遗传变异和演化方向。【方法】本研究于2021年10月至2022年6月收集了广州、深圳地区的动物医院、动物收容所和华南农业大学病猫的眼鼻口拭子、肛拭子样本,通过提取临床样本核酸、one step RT-PCR、常规PCR技术检测FCV、FPV及FHV-1;对阳性样品进行基因扩增及测序,利用DNAStar分析核苷酸序列相似性,使用MEGA 7.0构建系统发育树;使用克兰德尔−里斯猫肾(Crandell-Reese feline kidney,CRFK)细胞接种FCV、FHV-1阳性样品进行病毒分离,连续盲传至出现细胞病变,利用PCR、电子显微镜等技术鉴定分离毒株。【结果】379例具有临床症状的病猫中,FPV、FCV、FHV-1感染率分别为22.16%、19.00%和3.17%;病毒阳性率与猫只性别无关,6月龄及以下患猫中FCV、FPV检出率最高,分别为63.89%、58.33%,FHV-1在12月龄及以上患猫中阳性占比最高,为66.67%。已免疫“妙三多”疫苗的患猫中FCV、FHV-1、FPV均有检出,阳性率分别为75.00%、75.00%、20.24%。成功分离到7株FCV、1株FHV-1和2株FPV。7株FCV分离株全基因组与参考株的核苷酸相似性为75.0%~87.5%,7株FCV分离株形成了两大分支,GZ-1-249和GZ-1-184属于GI分支,而其他5株分离株均属于GII分支。14条FPV VP2基因序列与参考株的核苷酸相似性为97.4%~100.0%,14条序列与“妙三多”疫苗株M38246.1(FPV USA Cu4)等序列共同归属于一大分支。【结论】研究结果丰富了FCV、FPV和FHV-1相关流行病学数据,增强了对本地流行毒株的认识,为未来本土疫苗的研发和优化提供了重要支持。 展开更多
关键词 猫杯状病毒 猫细小病毒 猫疱疹病毒1型 分离 鉴定 遗传进化
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四川肉牛源疣状毛癣菌的分离鉴定、系统发育分析与药敏试验
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作者 王娅 李志国 +3 位作者 罗荣艳 刘瑞国 左之才 马晓平 《中国畜牧兽医》 北大核心 2026年第1期459-468,共10页
【目的】探究四川肉牛真菌性皮肤病的病原,为该病的防治提供参考。【方法】采集四川各地疑似皮肤癣病的患畜皮屑,用三点接种法将采集的样本接种于皮肤癣菌鉴别培养基,将分离得到的菌株经内部转录间隔区(ITS)序列扩增后通过NCBI数据库BL... 【目的】探究四川肉牛真菌性皮肤病的病原,为该病的防治提供参考。【方法】采集四川各地疑似皮肤癣病的患畜皮屑,用三点接种法将采集的样本接种于皮肤癣菌鉴别培养基,将分离得到的菌株经内部转录间隔区(ITS)序列扩增后通过NCBI数据库BLAST分析基因相似性并构建系统发育树,以10^(7) CFU/mL分离菌孢子悬液感染免疫抑制小鼠,观察临床症状和病理学特征,微量二倍稀释法探究分离菌耐药表型。【结果】从24个样本中分离到10株真菌(rntv01~rntv10)。PCR扩增结果显示,分离株均得到大小为681 bp的扩增片段;BLAST比对结果显示,分离株与疣状毛癣菌相似性为97%~100%;动物试验结果显示,免疫抑制小鼠感染该菌后皮肤出现被毛脱落、结痂、皮屑增多等症状,HE染色后观察到表皮角质层角化不全、炎性细胞增生,PAS染色后观察到大量菌丝侵染;药敏试验结果显示,除rntv10外,其余菌株对两性霉素B中介;分离菌对伊曲康唑敏感性不同,rntv09、rntv10敏感,rntv01、rntv04~rntv08中介,rntv02、rntv03耐药;rntv10对酮康唑敏感、对5-氟胞嘧啶中介,其余菌株均为耐药株;所有菌株对环吡酮胺中介,对氟康唑和特比萘芬耐药。【结论】四川肉牛真菌性皮肤病主要病原是疣状毛癣菌,该菌可引起小鼠皮肤的侵袭性感染,患病牛可用两性霉素B、伊曲康唑或环吡酮胺进行治疗。 展开更多
关键词 肉牛 疣状毛癣菌 分离鉴定 ITS序列 系统发育分析 药敏试验
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装配式框架结构隔震体系抗倒塌能力研究
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作者 吴忠铁 范萍萍 +2 位作者 李阳 吴为 黄亚龙 《地震工程学报》 北大核心 2026年第1期25-35,共11页
为研究装配式框架结构隔震体系的抗倒塌能力,利用PKPM软件设计了一个典型装配式框架结构隔震体系(ISPFS)模型。采用ETABS有限元软件建立相应的有限元模型,并对其进行增量动力分析(IDA)。以层间位移为损伤指标,获得模型在四个性能水准下... 为研究装配式框架结构隔震体系的抗倒塌能力,利用PKPM软件设计了一个典型装配式框架结构隔震体系(ISPFS)模型。采用ETABS有限元软件建立相应的有限元模型,并对其进行增量动力分析(IDA)。以层间位移为损伤指标,获得模型在四个性能水准下的易损性曲线,研究其易损性特点,利用安全储备系数(CMR)评价其抗倒塌能力。结果表明:装配式框架结构隔震体系主要存在上部结构失效、橡胶支座失效、隔震支墩(柱)失效三种失效模式,而橡胶支座失效是主要倒塌模式。控制橡胶支座的损伤是提升模型整体抗倒塌性能的关键,在罕遇地震下其安全储备系数为3.7,满足结构抗倒塌安全储备系数2.7的建议需求。同时,在极罕遇地震下模型仍然具有很好的抗倒塌能力。 展开更多
关键词 装配式框架结构 隔震体系 易损性 安全储备系数 抗倒塌能力
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Effect of Rhubarb Decoction on the Isolated Intestinal Movement of Ophicephalus argus 被引量:3
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作者 齐红莉 王睿睿 +5 位作者 郑宝楠 毛海涛 刘金兰 宋学军 宫雪燕 乔秀亭 《Agricultural Science & Technology》 CAS 2010年第3期101-103,共3页
[Objective] The aim of this study was to investigate effects of rhubarb decoction with different concentrations on the isolated intestinal movement performance of Ophicephalus argus,and to discuss its pharmacological ... [Objective] The aim of this study was to investigate effects of rhubarb decoction with different concentrations on the isolated intestinal movement performance of Ophicephalus argus,and to discuss its pharmacological mechanism.[Method] With RM6240C biological signal collection and processing system,tension values of the isolated intestine before and after the treatment by rhubarb decoction with different concentrations were recorded by the isolated organ method.[Result] Rhubarb decoction with concentration of 0.062 and 0.125 g/ml showed obvious enhancement on the isolated intestinal contraction of Ophicephalus argus,while rhubarb decoction with concentration of 0.250 and 0.500 g/ml showed inhibition on the isolated intestinal contraction of Ophicephalus argus.There was an extremely significant difference in rhubarb decoction with concentration of lower than 0.500 g/ml and more than 0.500 g/ml.With the increase of rhubarb concentration,the intestinal movement of Ophicephalus argus enhanced,but the contraction frequency did not change obviously.[Conclusion] Rhubarb decoction has remarkable effects on the contraction of smooth muscle in the isolated intestines of Ophicephalus argus. 展开更多
关键词 Rhubarb decoction Ophicephalus argus isolated intestine Physiological activity
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Isolate液优化精子在宫腔内人工授精的应用 被引量:7
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作者 苏迎春 孙莹璞 +2 位作者 刘新贵 陈爱军 陈秋菊 《中国卫生检验杂志》 CAS 1999年第6期F002-F002,共1页
关键词 人工授精 isolate 优化精子
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用CAPPI和PPI资料测定区域降水量精度比较 被引量:5
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作者 戴铁丕 詹煌 刘婉莉 《气象》 CSCD 北大核心 1995年第7期9-14,共6页
应用上海中心气象台714数字化天气雷达的体积扫描资料所得到的不同高度上的CAPPI资料和低仰角时PPI资料,估算区域降水量并得到降水量分布形势。然后采用平均校准法进行了校准,最后又与用雨量计网测得的区域降水量及其分布... 应用上海中心气象台714数字化天气雷达的体积扫描资料所得到的不同高度上的CAPPI资料和低仰角时PPI资料,估算区域降水量并得到降水量分布形势。然后采用平均校准法进行了校准,最后又与用雨量计网测得的区域降水量及其分布形势作了比较,得到一些有意义的结果。 展开更多
关键词 Cappi PPI 区域 降水量 校准 分布形势
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Fluctuations of Endogenous Hormones in Isolated Rice Embryos During Embryogenesis and Early Stages of Germination 被引量:2
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作者 杨军 赵洁 +1 位作者 周燮 杨弘远 《Acta Botanica Sinica》 CSCD 2003年第6期705-711,共7页
Fluctuations of levels of several endogenous plant hormones in isolated rice ( Oryza sativa ssp. japonica) embryos during early and mid-embryogenesis and early stages of germination were studied by enzyme-linked immun... Fluctuations of levels of several endogenous plant hormones in isolated rice ( Oryza sativa ssp. japonica) embryos during early and mid-embryogenesis and early stages of germination were studied by enzyme-linked immunosorbent assay (ELISA). Embryos were collected at different days after pollination (DAP) and different days after imbibition (DAI) of mature seeds. The contents of gibberellin(1) (GA(1)), abscisic acid (ABA), isopentenyladenine and isopentenyladenosine ( iPAs), zeatin and zeatin riboside ( ZRs) were immunochemically assayed. The GA(1) level was the highest among all hormones tested. The variations of GA(1) levels were opposite with the ABA levels, with some exceptions. During early and mid-embryogenesis, the levels of GA(1) and ABA were the highest at 4 DAP. From 8 to 18 DAP, GA(1) level declined, whereas the ABA level increased. During germination, GA(1) level increased at 2 DAI whereas simultaneously the ABA content decreased. The highest ratio of GA(1)/ABA was observed at 2 DAI The levels of iPAs and ZRs were maxima in the embryos at 4 DAP, decreased to a very low level and maintained constant thereafter. Our results provide further evidence that GA(1) plays an important role in the early stages of embryo development and germination. The balance between GA(1) and ABA, rather than their absolute contents, controls these processes throughout the development, whereas iPAs and ZRs may play important roles in early embryogenesis. The use of isolated embryos as starting material avoids the usual interferences with other tissues such as the endosperm. In addition, this is the first report dealing with the hormonal balance of early-embryos in rice. 展开更多
关键词 plant hormones EMBRYOGENESIS GERMINATION isolated embryo NICE
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Modeling on Prescribed Burning Width of Fire Isolated Belt in Pinus kesiya Forest 被引量:1
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作者 高仲亮 施绍军 +5 位作者 龙腾腾 李智 朱家进 张盛 宗发平 周劲峰 《Agricultural Science & Technology》 CAS 2012年第5期1123-1126,共4页
Based on field survey and measurement, and the simulated field burning test by indoor burning bed, a multiple linear regression model was established with factors of fuel load(x1), temperature(x2), fuel moisture c... Based on field survey and measurement, and the simulated field burning test by indoor burning bed, a multiple linear regression model was established with factors of fuel load(x1), temperature(x2), fuel moisture content(x3), wind velocity(x4), aspect(xs), slope(x6), forest height(x7), propagation velocity(x8), fire line intensity(xg) and prescribed burning width of fire isolated belt(y). The results showed that the multivari- ate linear model was y=-12.371 +4.182x1 +0.435x2 +0.013x3+0.083x4+0.017x5+0.916x6+ 0.540x7, and the influences of the factors on the prescribed burning width of fire isolated belt were in the order of x6, x7, x1, x4, x3, x2, x5. This model make it easier to establish fire isolated belt by using fuel characteristics, topographic factors, meteorological factors, and forest stand factors, providing basis for the development of prescribed burning and forest management fire. 展开更多
关键词 Prescribed burning Fire isolated belt Model
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