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Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity
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作者 Moawiah M.Naffaa 《Neural Regeneration Research》 SCIE CAS 2025年第6期1565-1581,共17页
Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inh... Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. Moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased complexity and restructuring of neural network structures, as well as the addition of new granule granule cells that aid in olfactory adaptation. Additionally, the manuscript underscores the importance of employing precise methodologies to elucidate the specific roles of adult neurogenesis amidst conflicting data and varying experimental paradigms. Understanding these processes is essential for gaining insights into the complexities of olfactory function and behavior. 展开更多
关键词 network adaptability NEUROGENESIS neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity
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现代集约化肉羊业主要关键技术研究与应用 被引量:1
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作者 赵有璋 李发弟 +11 位作者 姚军 张子军 王玉琴 蔡原 陈亚明 祝淑英 李永连 赵宗蕾 王敏芬 冯涛 郭健 杨富民 《中国草食动物》 2005年第2期3-9,共7页
专门化肉用种羊选定、引进后,通过适应性研究,在较大规模养羊业生产实践中,对现代集约化肉羊业的主要关键技术进行研究、完善和创新,组装集成并应用于生产。技术研究应用结果既为市场提供了大批专门化肉用种羊和优质安全的杂种肉羊,取... 专门化肉用种羊选定、引进后,通过适应性研究,在较大规模养羊业生产实践中,对现代集约化肉羊业的主要关键技术进行研究、完善和创新,组装集成并应用于生产。技术研究应用结果既为市场提供了大批专门化肉用种羊和优质安全的杂种肉羊,取得了高水平的研究成果及显著的经济效益和社会效益,又为我国目前正在迅速发展的集约化肉羊业提供了可靠的技术支持和理想的生产模式:从适宜的专门化肉羊品种到运用高效母羊快速扩繁技术,建立和完善有效的肉羊杂交利用体系,普遍应用种羊鲜、冻精生产大批肉用杂种羔羊,种植高产优质饲草及其科学加工调制和利用,建立严格兽医防疫制度,实行放牧+补饲或全舍饲的精细管理和集约化育肥,至生产优质、安全、标准肉羊,获得显著的经济效益和社会效益。 展开更多
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氧氟沙星对小鼠生殖毒性和致畸性的研究 被引量:1
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作者 沈红 吴国娟 +2 位作者 李焕荣 崔胜 程颖 《中国实验动物学报》 CAS CSCD 2005年第2期124-126,共3页
目的研究氧氟沙星对昆明系小鼠胚胎和胎鼠发育的影响,确定其是否存在生殖毒性和致畸性。方法①雄鼠分别灌服各剂量氧氟沙星,连续10d,末次给药24h后与母鼠合笼,在妊娠第三天取胚胎,记录各剂量组胚胎发育率。②孕鼠妊娠零天给药,分别经口... 目的研究氧氟沙星对昆明系小鼠胚胎和胎鼠发育的影响,确定其是否存在生殖毒性和致畸性。方法①雄鼠分别灌服各剂量氧氟沙星,连续10d,末次给药24h后与母鼠合笼,在妊娠第三天取胚胎,记录各剂量组胚胎发育率。②孕鼠妊娠零天给药,分别经口灌服高、中、低剂量[36、72和360mg(kg.bw)]氧氟沙星溶液,连续给药3d,在妊娠第三天收集胚胎,记录胚胎发育率。③孕鼠妊娠零天给药,分别经口灌服各剂量氧氟沙星溶液,连续给药10d,在妊娠第16天取出胎鼠,记录胎鼠体重、胎盘重、活胎数、胎鼠外观畸形和内脏畸形等指标。结果给药组与对照组相比,雄鼠服用高剂量组360mg(kg.bw)氧氟沙星对着床前胚胎发育影响显著(P<0.05),而中等剂量和低剂量组对着床前胚胎发育的影响不显著(P>0.05)。雌鼠服用不同剂量氧氟沙星对着床前胚胎发育影响不显著(P>0.05)。氧氟沙星对受孕鼠的活胎数和吸收胎数均无明显影响,给药组的活鼠体重、胎盘重均未见明显差异(P>0.05);药物组和对照组均未出现外观畸形和内脏畸形,也不存在剂量和效应关系。结论孕鼠服用不同剂氧氟沙星对昆明系小鼠胚胎和胎鼠发育无明显的影响,表明氧氟沙星对雌性鼠不具有明显的生殖毒性和致畸性;但雄鼠服用高剂量氧氟沙星对着床前胚胎发育影响显著。 展开更多
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高丹草新品种在河北平原农区的引进筛选 被引量:7
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作者 刘贵波 乔仁甫 《中国农学通报》 CSCD 2005年第6期383-386,394,共5页
在河北平原农区,通过对国内外11个高丹草新品种的产草量、粗蛋白产量、物候期、分蘖力、再生性、株高等性状的研究分析,结果表明:以青饲、青贮饲喂牛为目的,表现最好的品种为健宝,不仅产草量高、粗蛋白产量、分蘖能力、再生性、长势均... 在河北平原农区,通过对国内外11个高丹草新品种的产草量、粗蛋白产量、物候期、分蘖力、再生性、株高等性状的研究分析,结果表明:以青饲、青贮饲喂牛为目的,表现最好的品种为健宝,不仅产草量高、粗蛋白产量、分蘖能力、再生性、长势均较好。其次为晋草1号、瑞奥3号。高丹草在河北平原农区春播、夏播均可,春播可刈割三次,夏播可刈割二次。 展开更多
关键词 1
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波尔山羊批量胚胎移植莎能奶山羊 被引量:3
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作者 沈文正 马建涛 严飞 《西北农业学报》 CAS CSCD 北大核心 2005年第2期1-4,共4页
采用阴道栓+FSH超数排卵,经产供体波尔山羊22只,在放栓后第9~11天,连续4d递减量肌肉注射FSH。22只供体羊发情与纯种波尔山羊种公羊配种后第7天,手术回收输卵管中早期发育胚胎再经手术移入同期发情的受体奶山羊输卵管内妊娠产仔。结果表... 采用阴道栓+FSH超数排卵,经产供体波尔山羊22只,在放栓后第9~11天,连续4d递减量肌肉注射FSH。22只供体羊发情与纯种波尔山羊种公羊配种后第7天,手术回收输卵管中早期发育胚胎再经手术移入同期发情的受体奶山羊输卵管内妊娠产仔。结果表明:1获得373枚早期胚胎,其中A级胚胎占31.1%(85/273),B级胚胎占49.5%(135/273),异常胚胎占19.4%(53/273)。2将167枚7日龄可用胚胎(A级和B级)移植147只受体羊输卵管内,移植后35d,妊娠98只,妊娠率为67%(98/147),83只羊足月产羔为89只,产羔率为85%(89/98),20只受体移植了两枚胚胎,只有6只产双羔。3羔羊出生重平均为3.7±0.54kg。每只供体羊平均产羔4.05只。胚胎移植所得羔羊的初生重与自然繁殖波尔羔羊无显著差异(P>0.05)。试验证明,山羊胚胎移植计划可使良种群体繁殖率提高3~5倍,优秀个体繁殖力提高6~8倍,从而加快纯种山羊的繁殖。 展开更多
关键词 FSH
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寄主植物对甜菜夜蛾的发育和繁殖及体内酯酶活性的影响 被引量:17
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作者 李子玲 韦绥概 +3 位作者 韦飚 梁忠毅 杨海菊 王仕红 《昆虫知识》 CAS CSCD 北大核心 2005年第3期284-289,共6页
在恒温(2 8±1 )℃条件下考察了葱、苋菜、豇豆、蕹菜、菜心5种寄主植物对甜菜夜蛾SpodopteraexiguaH櫣bner的营养效应及体内羧酸酯酶、乙?铛ッ富钚缘挠跋?,结果表明,不同寄主植物对甜菜夜蛾幼虫和蛹的发育历期、存活率、蛹... 在恒温(2 8±1 )℃条件下考察了葱、苋菜、豇豆、蕹菜、菜心5种寄主植物对甜菜夜蛾SpodopteraexiguaH櫣bner的营养效应及体内羧酸酯酶、乙?铛ッ富钚缘挠跋?,结果表明,不同寄主植物对甜菜夜蛾幼虫和蛹的发育历期、存活率、蛹重、雌成虫产卵量等有显著影响,其中对雌成虫产卵量的影响最大。雌成虫产卵量最高为取食菜心的处理,其次是取食葱的处理。寄主植物对甜菜夜蛾体内羧酸酯酶、乙酰胆碱酯酶活性也有显著影响,但这些酶的活性与发育历期、存活率、产卵量无明显相关性。在进行预测预报、田间防治时应充分考虑寄主植物对甜菜夜蛾发育历期、产卵量、解毒酶活性的影响。 展开更多
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Expression of estrogen receptor (ER) -α and -βtranscripts in the neonatal and adult rat cerebral cortex, cerebellum, and olfactory bulb 被引量:1
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作者 GuoXZ SuJD 《Cell Research》 SCIE CAS CSCD 2001年第4期321-324,共4页
In the present study expression of estrogen receptor subtype -alpha (ERalpha) and -beta (ERbeta) in the cerebral cortex, cerebellum, and olfactory bulb was investigated and compared between neonatal (1 to approximatel... In the present study expression of estrogen receptor subtype -alpha (ERalpha) and -beta (ERbeta) in the cerebral cortex, cerebellum, and olfactory bulb was investigated and compared between neonatal (1 to approximately 3-days-old) and adult (250 to approximately 350 g) rats, using reverse transcription-polymerase chain reaction (RT-PCR). No ERalpha transcripts were detectable in the adult cerebellum and olfactory bulb, whereas very weak expression of ERalpha was present in the adult cerebral cortex. No significant difference in ERbeta transcripts was detectable between the neonatal and adult rats. While transcripts for both ER subtypes were co-expressed in these brain areas of neonatal rats, although ERalpha expression was significantly weaker than ERbeta. Even in the cerebral cortex known to contain both ER subtypes in adult rats, ERalpha transcripts in neonatal rats were much higher than in adult. These observations provide evidence for the existence of different expression patterns of ERalpha/ERbeta transcripts in these three brain areas between the neonatal and adult rats, suggesting that each ER subtype may play a distinct role in the regulation of differentiation, development, and functions of the brain by estrogen. 展开更多
关键词 ANIMALS Animals Newborn Brain CEREBELLUM Cerebral Cortex Estrogen Receptor alpha Estrogen Receptor beta Female Male Olfactory bulb RNA Messenger RATS Rats Sprague-Dawley Receptors Estrogen Research Support Non-U.S. Gov't Transcription Genetic
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SEIHCRD Model for COVID-19 Spread Scenarios,Disease Predictions and Estimates the Basic Reproduction Number,Case Fatality Rate,Hospital,and ICU Beds Requirement 被引量:1
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作者 Avaneesh Singh Manish Kumar Bajpai 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第12期991-1031,共41页
We have proposed a new mathematical method,the SEIHCRD model,which has an excellent potential to predict the incidence of COVID-19 diseases.Our proposed SEIHCRD model is an extension of the SEIR model.Three-compartmen... We have proposed a new mathematical method,the SEIHCRD model,which has an excellent potential to predict the incidence of COVID-19 diseases.Our proposed SEIHCRD model is an extension of the SEIR model.Three-compartments have added death,hospitalized,and critical,which improves the basic understanding of disease spread and results.We have studiedCOVID-19 cases of six countries,where the impact of this disease in the highest are Brazil,India,Italy,Spain,the United Kingdom,and the United States.After estimating model parameters based on available clinical data,the modelwill propagate and forecast dynamic evolution.Themodel calculates the Basic reproduction number over time using logistic regression and the Case fatality rate based on the selected countries’age-category scenario.Themodel calculates two types of Case fatality rate one is CFR daily,and the other is total CFR.The proposed model estimates the approximate time when the disease is at its peak and the approximate time when death cases rarely occur and calculate how much hospital beds and ICU beds will be needed in the peak days of infection.The SEIHCRD model outperforms the classic ARXmodel and the ARIMA model.RMSE,MAPE,andRsquaredmatrices are used to evaluate results and are graphically represented using Taylor and Target diagrams.The result shows RMSE has improved by 56%–74%,and MAPE has a 53%–89%improvement in prediction accuracy. 展开更多
关键词 COVID-19 CORONAVIRUS SIER model SEIHCRD model parameter estimation mathematical model India Brazil United Kingdom United States Spain Italy hospital beds ICU beds basic reproduction number case fatality rate
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A Simplified Method to Calculate the Wet Bulb Globe Temperature(WBGT)
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作者 ZHANG Lei,MENG Qing-lin,ZHAO Li-hua,ZHANG Yu-feng(State Key Laboratory of Subtropical Building Science,South China University of Technology,Guangzhou,Guangdong 510640,China) 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期40-44,共5页
Wet bulb globe temperature(WBGT)is a comprehensive index obtained mainly from three parameters:black globe temperature(Tg),wet bulb temperature(Tw),and dry bulb temperature(Ta).While in field observation and numerical... Wet bulb globe temperature(WBGT)is a comprehensive index obtained mainly from three parameters:black globe temperature(Tg),wet bulb temperature(Tw),and dry bulb temperature(Ta).While in field observation and numerical simulation,black globe temperature and wet bulb temperature were not easy to obtain,so WBGT was difficult to measure and calculate directly.In order to solve this problem,air dry bulb temperature,wet bulb temperature,globe temperature,relative humidity,mean air velocity,solar radiation and wet bulb globe temperature were collected during the summer(July)in Guangzhou.Correlation analysis and regression analysis were used to get a simplified method to calculate WBGT.The results showed that dry bulb temperature,relative humidity,solar radiation and WBGT were interrelated to some extent.These three parameters could be used in the simplified method to predict WBGT,and the linear correlation and precision of this model were high.In addition,we used the measured data to verify the simplified method,and the results showed that the error of the calculated value and the measured value was all below 5%,which means the simplified calculating method is feasible and can be used in field observation and simulation research of urban thermal environment. 展开更多
关键词 hot and humid REGIONS urban thermal environment WET bulb globe TEMPERATURE MULTIVARIATE linear regression
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Co-localization of two-color rAAV2-retro confirms the dispersion characteristics of efferent projections of mitral cells in mouse accessory olfactory bulb
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作者 Ning Zheng Zhi-Zhong Wang +6 位作者 Song-Wei Wang Fang-Jia Yang Xu-Tao Zhu Chen Lu Anne Manyande Xiao-Ping Rao Fu-Qiang Xu 《Zoological Research》 SCIE CAS CSCD 2020年第2期148-156,共9页
The accessory olfactory bulb(AOB), located at the posterior dorsal aspect of the main olfactory bulb(MOB), is the first brain relay of the accessory olfactory system(AOS), which can parallelly detect and process volat... The accessory olfactory bulb(AOB), located at the posterior dorsal aspect of the main olfactory bulb(MOB), is the first brain relay of the accessory olfactory system(AOS), which can parallelly detect and process volatile and nonvolatile social chemosignals and mediate different sexual and social behaviors with the main olfactory system(MOS). However, due to its anatomical location and absence of specific markers, there is a lack of research on the internal and external neural circuits of the AOB. This issue was addressed by singlecolor labeling and fluorescent double labeling using retrograde rAAVs injected into the bed nucleus of the stria terminalis(BST), anterior cortical amygdalar area(ACo), medial amygdaloid nucleus(MeA), and posteromedial cortical amygdaloid area(PMCo) in mice. We demonstrated the effectiveness of this AOB projection neuron labeling method and showed that the mitral cells of the AOB exhibited efferent projection dispersion characteristics similar to those of the MOB. Moreover, there were significant differences in the number of neurons projected to different brain regions, which indicated that each mitral cell in the AOB could project to a different number of neurons in different cortices. These results provide a circuitry basis to help understand the mechanism by which pheromone information is encoded and decoded in the AOS. 展开更多
关键词 Accessory OLFACTORY bulb Efferent projections RETROGRADE rAAVs Projection neuron labeling Dispersion characteristics CIRCUITRY basis
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HIV prevalence in suspects attending Sir Sunder Lal Hospital 被引量:3
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作者 Ajay Singh 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第1期69-73,共5页
Objective:To assess the sero-positivity rate of HIV infection among clinically suspected subjects of reproductive age group(15-49 years),biological and behavioral characteristics of the subjects gender specific variat... Objective:To assess the sero-positivity rate of HIV infection among clinically suspected subjects of reproductive age group(15-49 years),biological and behavioral characteristics of the subjects gender specific variation of sero-positivity rale,and the differentials of the sero-positivity rate for the history of blood transfusion or blood products or other organs,history of needle exposure and symptoms of morbidity.Methods:Study is based on the retrospective data of the calendar year 2005 obtained from Voluntary Counseling and Testing Centre(VCTC)(now renamed as ICTC),Department of Microbiology,I.M.S.,B.H.U..Varanasi.These cases were either referred by the consultants of different OPD'S of Sir Sunderlal Hospital or came voluntarily for knowing their HIV status.About 2-3 mL of blood samples were collected in a plain vial and tested for HIV status by strategy Ⅱ/Ⅲ as per WHO/NACO guidelines.Results:Overall sero-positivity of HIV was 15.3%(18.1%in males and 12.2%in females) which increased 6-7 folds in the age group 35-49 years as compared to 15-24 years in both the sexes.Sero-positivity rate in male migrants was 43.1%,while in female migrants it was 18.7%.The history of multiple sexual contacts was about 3 times higher in males as compared to females;predominantly it was very high in male migrants(67.7%) as compared to male non-migrants(15.8%).History of multiple sexual contacts was not uncommon in females and it was 25.0%in female migrants and 9.7%in non-migrant females.The sero-positivity rate with the history of multiple sexual contacts was 45.4%in males and 60.3%in females,while without history of multiple sexual contacts these were only 2.8%and 5.3%respectively.Sero-positive cases had on an average 3.6±1.7 various morbidity symptoms as compared to 0.7±1.1 in sero-negatives.It is to be noted that sero-positivity rate was more in those females who seemed apparently healthy compared to those presenting with some of the symptoms;vice versa,in males presenting with some symptoms HIV infection was 7 times higher than those without symptoms.Conclusions:The findings indicate a high sero-positivity among both the genders.Multiple heterosexual contacts,especially,in migrants are the main root of transmission of HIV.These are causing spread of HIV to their spouses.The multiple sexual contacts in the society,especially,among non migrant females of this region are indicating the distortion of traditions and cultures which are a serious concern and may lead to HTV infection on the rise.Awareness program to the susceptible group is the need to reduce further spread of HIV. 展开更多
关键词 Migration Multiple sexual contacts HETEROSEXUAL HIV AIDS Reproductive Antibiotic therapy HIV prevalence SEROPOSITIVITY Transimission HIV infection Sexual contact MIGRANT BLOOD sample Biological characteristic BLOOD TRANSFUSION Needle exposure Awareness
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Controlling of crustacean zooplankton reproduction in biological activated carbon (BAC) filters by strengthen operation and management of conventional process
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作者 刘丽君 张金松 +1 位作者 李小伟 赫俊国 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第5期661-666,共6页
To counter the mass reproduction and penetration of crustacean zooplankton in Biological Activated Carbon(BAC)filters which may result in the presence of organisms in potable water and water pollution,this paper analy... To counter the mass reproduction and penetration of crustacean zooplankton in Biological Activated Carbon(BAC)filters which may result in the presence of organisms in potable water and water pollution,this paper analyzed the factors affecting organisms' reproduction in BAC filters.A comparative study was performed on the density and composition of crustacean zooplankton of the concerned water treatment units of two advanced water plants(Plant A and B)which with the same raw water and the same treatment technique in southern China.The results obtained show that the crustaceans' density and composition was very different between the sand filtered water of Plant A and Plant B.which Harpacticoida bred sharply in the sediment tanks and penetrated sand filter into BAC filters was the primary reason of crustaceans reproduce in BAC filters of Plant A.For prevention of the organisms reproduction in BAC,some strengthen measures was taken including pre-chlorination,cleaning coagulation tanks and sediment tanks completely,increasing sludge disposal frequency to stop organisms enter BAC filters,and the finished water quality was improved and enhanced. 展开更多
关键词 CRUSTACEAN zooplankton reproduction BAC filter CONVENTIONAL treatment PROCESS STRENGTHEN operation and management tap water quality
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贯郁胶囊对嗅球损毁大鼠行为及中枢单胺类神经递质的影响 被引量:7
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作者 王景霞 张建军 +5 位作者 钟赣生 张德芹 胡素敏 李伟 欧丽娜 高学敏 《中国中药杂志》 CAS CSCD 北大核心 2005年第10期782-785,共4页
目的:研究贯郁胶囊对嗅球损毁大鼠行为及大脑皮层单胺类神经递质的影响。方法:采用敞箱法、跳台法观察嗅球损毁模型大鼠的行为变化;采用高效液相电化学方法分析贯郁胶囊对嗅球损毁模型大鼠神经递质含量的影响。结果:嗅球损毁模型大鼠敞... 目的:研究贯郁胶囊对嗅球损毁大鼠行为及大脑皮层单胺类神经递质的影响。方法:采用敞箱法、跳台法观察嗅球损毁模型大鼠的行为变化;采用高效液相电化学方法分析贯郁胶囊对嗅球损毁模型大鼠神经递质含量的影响。结果:嗅球损毁模型大鼠敞箱实验的爬格数和站立数显著增加,跳台实验的错误次数明显增多(P<0.01);大脑皮层5羟色胺(5HT)的含量明显降低,3,4二羟基苯乙酸(DOPAC)/多巴胺(DA)均明显升高(P<0.01)。贯郁胶囊1.2,0.6g·kg-1均可降低嗅球损毁大鼠敞箱实验的爬格数和站立数,减少跳台实验的错误次数(P<0.01,P<0.05),提高大脑皮层中5HT的含量,并使DOPAC/DA恢复正常(P<0.01)。结论:贯郁胶囊能改善嗅球损毁模型大鼠的行为异常,作用机制与调节5HT的含量、DA的代谢有关。 展开更多
关键词 (DA) 5-HT 5-
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Genetic Variability and Reproduction Structure of <i>Corbicula japonica</i>in Major Fishing Brackish Lakes in Japan
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作者 Tsudzumi Mito Tomomi Tanaka Futoshi Aranishi 《Open Journal of Marine Science》 2014年第3期174-184,共11页
Corbicula japonica is the best-known bivalve inhabiting widely in brackish estuaries and lakes in Japan. Although this species has been most commercially important species of inland fisheries in Japan, the gradual dec... Corbicula japonica is the best-known bivalve inhabiting widely in brackish estuaries and lakes in Japan. Although this species has been most commercially important species of inland fisheries in Japan, the gradual decline in its production over 40 years caused not only economic problems in fishery industry but also ecological disturbances in biodiversity conservation. The aim of this study was to evaluate the reproduction structure of C. japonica populations in major fishing brackish lakes based on the genetic diversity inferred by mitochondrial DNA sequence analysis of the cytochrome oxidase c subunit I gene. Of a total of 188 C. japonica individuals collected in Lakes Shinji, Jusan, Ogawara and Abashiri, 25 haplotypes were obtained, and only the haplotype HT01 was apparent with relatively high abundance in all lakes. Minimum spanning network analysis of haplotypes showed different population structures between Lake Shinji and Lakes Jusan, Ogawara and Abashiri. In addition, pairwise population genetic distance FST and ΦST values were significantly higher in Lake Shinji than Lakes Jusan, Ogawara and Abashiri. The mismatch distribution analysis showed unimodal profile for Lakes Jusan and Ogawara and bimodal profile for Lakes Shinji and Abashiri. Those results indicate a recent population expansion in all lakes, and Lakes Shinji and Abashiri and Lakes Jusan and Ogawara maintained continuous reproduction structure and suffered to rapid population growth, respectively. 展开更多
关键词 CORBICULA JAPONICA BRACKISH LAKES Genetic Diversity reproduction Structure Cytochrome Oxidase c Subunit I Gene
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猪繁殖与呼吸综合征疫苗研究进展 被引量:18
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作者 杨金雨 仇华吉 童光志 《动物医学进展》 CSCD 2005年第5期28-31,共4页
猪繁殖与呼吸综合征是一种引起母猪繁殖障碍和新生仔猪呼吸道症状及高死亡率的传染病。已几乎遍极世界所有养猪国家,在中国的流行和分布也日益广泛,危害日益严重。此病的传播给世界养猪业造成严重经济损失,受到国内外学者的高度重视,对... 猪繁殖与呼吸综合征是一种引起母猪繁殖障碍和新生仔猪呼吸道症状及高死亡率的传染病。已几乎遍极世界所有养猪国家,在中国的流行和分布也日益广泛,危害日益严重。此病的传播给世界养猪业造成严重经济损失,受到国内外学者的高度重视,对此病的研究也正在逐渐深入,特别是免疫学及其疫苗的研究正日益受到关注。文章就猪繁殖与呼吸综合征病毒的灭活疫苗、弱毒疫苗和基因工程疫苗的研究进展和使用现状做了系统地阐述,特别是通过合理地选择和使用免疫佐剂,如γ干扰素、霍乱毒素及可溶性β葡聚糖等来改进疫苗作用方面进行了阐述。 展开更多
关键词 使 Γ
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小型太阳能气泡泵吸收式制冷机研究 被引量:3
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作者 周永红 《制冷与空调(四川)》 2005年第2期42-45,26,共5页
本文确定了设计计算参数下小型太阳能气泡泵吸收式制冷机制冷循环中各状态点参数,进行了发生器、冷凝器、蒸发器、吸收器、溶液热交换器的热负荷计算和加热热水、冷水、冷却水、稀溶液等循环介质的流量计算。进行了发生器、冷凝器、蒸... 本文确定了设计计算参数下小型太阳能气泡泵吸收式制冷机制冷循环中各状态点参数,进行了发生器、冷凝器、蒸发器、吸收器、溶液热交换器的热负荷计算和加热热水、冷水、冷却水、稀溶液等循环介质的流量计算。进行了发生器、冷凝器、蒸发器、吸收器、溶液热交换器等换热设备所需的传热面积计算。根据求得的传热面积确定了各换热设备的传热管数,计算了热水进出口配管、冷却水进口配管、冷媒水进口配管的内径尺寸,为开发小型吸收式制冷机提供了一定的理论和实践基础。 展开更多
关键词
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PRRSV间接免疫荧光检测法的建立和应用 被引量:17
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作者 彭长凌 高崧 刘秀梵 《中国兽医科技》 CSCD 北大核心 2005年第4期256-260,共5页
以猪生殖与呼吸综合征病毒(PRRSV) ATCC VR 2332 株人工单独感染3 头3 周龄仔猪,并用PRRSV ATCC VR 2332株和猪圆环病毒2型(PCV2)联合感染2 头3 周龄仔猪,每日检查试验猪体温、采食情况及临床表现,并用HerdChek IDEXX 试剂盒测其血清抗... 以猪生殖与呼吸综合征病毒(PRRSV) ATCC VR 2332 株人工单独感染3 头3 周龄仔猪,并用PRRSV ATCC VR 2332株和猪圆环病毒2型(PCV2)联合感染2 头3 周龄仔猪,每日检查试验猪体温、采食情况及临床表现,并用HerdChek IDEXX 试剂盒测其血清抗体。PRRSV+PCV2联合感染猪分别在感染后1、3周剖杀,PRRSV单独感染猪和健康对照猪分别在感染后1、2和3周剖杀,对全部试验猪的肺组织进行灌洗处理以获得肺泡巨噬细胞(PAM),用PAM进行抹片,同时用肺组织直接进行触片做间接免疫荧光(IIF)检测。结果表明,用所获得的3 株单克隆抗体均检测到人工感染猪肺组织中的PRRSV抗原。另外,用IIF检测7 头临床疑似PRRS病猪的PAM抹片,其中沭阳县的2头猪呈现阳性反应;对这2头猪的肺组织进行病毒分离,在盲传到第4代时Marc 145细胞上产生明显的细胞病变,进一步证实用所获得的3株单克隆抗体检测临床样品的结果准确而可靠,且获得的3株单克隆抗体均可通过IIF用于检测猪肺组织中的PRRSV抗原。 展开更多
关键词 PRRSV 2 ATCC
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The Growth of Roots and Green Leaves of <i>Allium cepa</i>L. after the Removal of Different Parts of the Bulb
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作者 A. Yu. Budantsev 《American Journal of Plant Sciences》 2013年第5期972-975,共4页
The dynamics of the growth of roots and leaves of the Allium cepa L. after the mechanical removal of a part of the root system or the bulb was studied. It was shown that, after surgical interference, the potency for o... The dynamics of the growth of roots and leaves of the Allium cepa L. after the mechanical removal of a part of the root system or the bulb was studied. It was shown that, after surgical interference, the potency for organogenesis is retained, although it is weakened. 展开更多
关键词 Organogenesis bulbs of Allium Cepa REMOVAL of bulb and Root Parts GROWTH of ROOTS and LEAVES
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Stress Analysis of the Glass Bulb of 35-inch(V)120°Color Picture Tube
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作者 童林夙 TorongeyPeterKimanus 《Journal of Southeast University(English Edition)》 EI CAS 1996年第2期53-56,共4页
A simulation of the stress analysis for a vacuum glass bulb of 35 inch (V) 120° Color Picture Tube(CPT) has been developed. It is shown that extra large deflection angle Color Picture Tube is viable. Increase ... A simulation of the stress analysis for a vacuum glass bulb of 35 inch (V) 120° Color Picture Tube(CPT) has been developed. It is shown that extra large deflection angle Color Picture Tube is viable. Increase in the deflection angle will shorten the de 展开更多
关键词 FEM VACUUM stress analysis color PICTURE tube EXTRA large DEFLECTION angle GLASS bulb
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高致病性猪蓝耳病病毒湖北分离株细胞培养特性研究 被引量:2
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作者 杨克礼 曹宏云 +8 位作者 田永祥 梁望旺 伍锐 段正赢 刘泽文 邓均华 郭锐 周丹娜 徐涤平 《江西农业学报》 CAS 2010年第9期103-106,共4页
高致病性猪蓝耳病是近年来严重危害我国养猪业的一种传染病.为了探明高致病性猪蓝耳病病毒在Marc145细胞上的增殖特性,本研究在分离获得高致病性猪蓝耳病病毒湖北株的基础上进行了细胞培养特性研究.结果表明:高致病性猪蓝耳病病毒湖北株... 高致病性猪蓝耳病是近年来严重危害我国养猪业的一种传染病.为了探明高致病性猪蓝耳病病毒在Marc145细胞上的增殖特性,本研究在分离获得高致病性猪蓝耳病病毒湖北株的基础上进行了细胞培养特性研究.结果表明:高致病性猪蓝耳病病毒湖北株在Marc145细胞上增殖所需的最佳条件分别为:营养液最佳血清含量为10%;最佳pH值为7.2~7.4;细胞最佳培养密度为105~ 2×105/mL;病毒增殖的最佳接毒量为8×103 TCID50/mL;病毒增殖的最佳吸附时间为37 ℃,60 min;最佳收毒时间为接毒后60~84 h;病毒最佳冻融次数为反复冻融3次. 展开更多
关键词 Culture Characteristics Cell Marc145
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