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P2X receptors in maintenance and differentiation of neural progenitor cells 被引量:1
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作者 Henning Ulrich Peter Illes 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第23期2040-2041,共2页
Purinergic receptors are among the first cell surface receptors expressed during embryonic development (Burnstock and Ulrich, 2011). These are characterized based on their pharmacological properties of being activat... Purinergic receptors are among the first cell surface receptors expressed during embryonic development (Burnstock and Ulrich, 2011). These are characterized based on their pharmacological properties of being activated by adenosine or purine/pyrimidine nucleotides as P1 and P2 receptors. P2 receptors are further classified by their structure as P2Y metabotropic and P2X ionotropic receptors. 展开更多
关键词 P2x receptors in maintenance and differentiation of neural progenitor cells
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Changes of the expression of CCNL2 gene during the differentiation of P19 cells to cardiac myocytes
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作者 Zhiwen Jiang Lili Zhuo Jie Gong Rong Yang Yanhui Sheng Xiangqing Kong Kejiang Cao 《Journal of Nanjing Medical University》 2009年第4期275-278,共4页
Objective: To investigate the changes of cyclin L2(CCNL2) gene mRNA and protein during the differentiation of P19 cells to cardiac myocytes, and to explore the relationship between CCNL2 gene and the differentiatio... Objective: To investigate the changes of cyclin L2(CCNL2) gene mRNA and protein during the differentiation of P19 cells to cardiac myocytes, and to explore the relationship between CCNL2 gene and the differentiation of cardiac myocytes. Methods: P19 cells were cultured with 0.9% DMSO for 18 days. Western blots of cardiac troponin I (cTnI) were used to identify cell differentiation. Total RNA was extracted from P19 cells during the process of differentiation at various time points:pre-differentiation(Day 0), and Day 1 to Day 18. The expression levels of CCNL2 gene mRNA and protein were evaluated by RT-PCR and Western blot, respectively. Results: After being induced to differentiate by DMSO for 4 days in suspension, spontaneously and rhythmically beating ceils were seen at 8 day, which were cTnI-positive. In P19 cells, both the expression level of CCNL2 gene mRNA and protein were gradually down-regulated. Conclusion: Both the expression of CCNL2 gene and protein were down-regulated during the process of the differentiation of P19 cells into cardiac myocytes, suggesting a possible role for this cyclin in their differentiation. 展开更多
关键词 cyclin l2 protein gene P19 cells cell differentiation
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Population genetic diversity and regional differentiation of Chinese forest frog s (Rana chensinensis) in Heilongjiang Province 被引量:6
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作者 肖向红 郑冬 +1 位作者 李枫 刘学东 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第1期40-42,共4页
The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields o... The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields of 8 regions in Heilongjiang Province. Totally 78 polymorphic DNA loci were amplified by 10 RAP D primers. By genetic distance analysis and phylogenetic tree reconstruction wit h the Neighbor-Joining (NJ) method the results showed that the populations of Ch inese forest frogs distributed in 8 regions existed great differentiation (Avera ge Fst=0.347, SD=0.235) while there was the paradox between geographic distances and genetic distances. Based on geographic and geological data, a hypothesis wa s posed that it is very possible that the hilly lands in the downstream of the S onghua River and the Heilong River were the center of the origin of the Chinese forest frogs in Heilongjiang Province. And mainly through the Songhua River syst em, the Chinese forest frogs dispersed into the Songneng Plain from the Sanjiang Plain whereas the Fangzheng region became a sub-center for the western dispersi on. 展开更多
关键词 Chinese forest frogs (Rana chensinensis) Population genetics Regiona l differentiation
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Identification of Differentially Expressed Genes in Sweetpotato Storage Roots Between Kokei No.14 and Its Mutant Nongdafu 14 Using PCR-Based cDNA Subtraction 被引量:1
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作者 CHEN Wei ZHAI Hong +3 位作者 YANG Yuan-jun HE Shao-zhen LIU De-gao LIU Qing-chang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第4期589-595,共7页
The contents of earotenoids in the storage root of sweetpotato, Ipomoea batatas (L.) Lam. vary dramatically among different cultivars. However, so far little is known about the regulation of carotenoids synthesis in... The contents of earotenoids in the storage root of sweetpotato, Ipomoea batatas (L.) Lam. vary dramatically among different cultivars. However, so far little is known about the regulation of carotenoids synthesis in sweetpotato. In our laboratory, we identified a novel sweetpotato mutant, Nongdafu 14, which is a homogenous mutant derived from the wild type Kokei No. 14. The contents of carotenoids in the storage root of Nongdafu 14 were analyzed using high performance liquid chromatography (HPLC), and it was found that the amount of carotenoids, [3-carotene, lutein and zeaxantion, three major types of earotenoids in sweetpotato storage roots, increased 2-26 folds in Nongdafu 14 compared to Kokei No. 14. Suppression subtractive hybridization (SSH) was used to identify genes that were differentially expressed in Nongdafu 14, and a differentially expressed eDNA library was constructed using the eDNA of Nongdafu 14 storage roots as tester and that of Kokei No. 14 storage roots as driver. Out of the 1 530 clones sequenced, we identified 292 nonredundant ESTs. GO and KEGG analyses of these differentially expressed ESTs indicated that diverse metabolism pathways were affected and candidate genes involved in regulation of carotenoids synthesis are suggested. 展开更多
关键词 lpomoea batatas (l.) lam. carotenoids suppression subtractive hybridization differentially expressed ESTs
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CD40L基因c.509A>G突变的X连锁高IgM综合征1例
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作者 王旭 李帅全 +6 位作者 赵雪莲 王西阁 周玉洁 姚小静 宋丽丽 臧文涛 樊淑丹 《中国小儿血液与肿瘤杂志》 CAS 2024年第1期57-60,65,共5页
1病例资料患儿,男,4岁5月龄,以“口唇苍白10余天、腹泻1周余”为主诉于2020年8月26日就诊于我院。患儿于10余天前无明显诱因出现口唇苍白,伴活动后乏力,无发热、咳嗽、流涕,无头痛、晕厥,无鼻衄、血尿、黑便。1周前患儿出现腹泻,稀水至... 1病例资料患儿,男,4岁5月龄,以“口唇苍白10余天、腹泻1周余”为主诉于2020年8月26日就诊于我院。患儿于10余天前无明显诱因出现口唇苍白,伴活动后乏力,无发热、咳嗽、流涕,无头痛、晕厥,无鼻衄、血尿、黑便。1周前患儿出现腹泻,稀水至稀糊状,5?6次/天,无粘液脓血便,伴低热,体温最高37.5℃,半天前至我院门诊就诊,查血常规:白细胞2.82×10^(9)/L,中性粒细胞百分比28.0%,淋巴细胞百分比47.9%,血红蛋白50g/L,血小板522×10^(9)/L. 展开更多
关键词 口唇苍白 粘液脓血便 周前 中性粒细胞百分比 x连锁 病例资料 晕厥 CD40l
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Differential Expression Analysis of Genie Male Sterility A/B Lines in Chinese Cabbage-Pak-Choi (Brassica campestris ssp. chinensis Makino) 被引量:3
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作者 WANGYong-qin CAOJia-shu 《Agricultural Sciences in China》 CAS CSCD 2003年第2期195-199,共5页
To determine differential expression of genie male sterility A/B lines in Chinese cabbage-pak-choi (Brassica campestris ssp. chinensis Makino var. communis Tsen et Lee), we used the RNA fingerprinting technique, cDNA-... To determine differential expression of genie male sterility A/B lines in Chinese cabbage-pak-choi (Brassica campestris ssp. chinensis Makino var. communis Tsen et Lee), we used the RNA fingerprinting technique, cDNA-AFLP analysis, in different developmental stages and different tissues. While no obvious differential expressions were observed in rosette leaves, florescence leaves, and scapes, some differential expressions were found in alabstrums of A/B lines and among leaves, scapes and alabstrums. We analyzed the al-abstrums collected in different developmental stages with 10 primer combinations. We got a unique band between middle size alabstrums and large alabstrums in B line in one of the ten pair primers, and in another one pair, one band reflecting a higher gene-expression level in A line than that in B line was obtained. No unique bands were found with the other primer combinations. The bands reflecting different gene-expression level were confirmed by Northern hybridization. The results indicated that cDNA-AFLP was a suitable tool for studying differential expression of genie male sterility in plants. SDS-polyacrylamide gel electrophoresis patterns of soluble proteins further verified the difference in A/B lines. 展开更多
关键词 Chinese cabbage Brassica campestris l. (syn. B. rapa l.) Genie male sterility differential expression CDNA-AFlP SDS-PAGE
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DIFFERENTIAL SCANNING CALORIMETRY AND X-RAY DIFFRACTION STUDIES ON AGING BEHAVIOR OF Zn-Al ALLOYS 被引量:2
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作者 X.L. Xu, Z. W. Yu, S.J. Ji, J.C. Sun and Z.K. Hei (Dalian Maritime University, Dalian 116024, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2001年第2期109-114,共6页
Decomposition processes of the quenched Zn-Al alloys were studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the stabilities o... Decomposition processes of the quenched Zn-Al alloys were studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the stabilities of supersaturated solid solution (SSS) of Zn-Al alloy and α' phase formed by quenching would reduce with the increase of Zn content and the precipitation of η-Zn phases even when aging at ambient temperature, so that the exothermic precipitation peak in DSC curve would disappear. The activation energy of the η-Zn precipitation and the reaction enthalpy were calculated and measured. The kinetics of α' decomposition or η-Zn formation was determined by XRD. The microstructure change during aging was observed by TEM. 展开更多
关键词 Aging of materials Aluminum alloys differential scanning calorimetry x ray diffraction
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A new method of detecting interferogram in differential phase-contrast imaging system based on special structured x-ray scintillator screen 被引量:6
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作者 刘鑫 郭金川 牛憨笨 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期193-197,共5页
An x-ray scintillator screen with a special structure, functioning as detector and analyser grating, was proposed for collecting the interferogram of differential phase contrast imaging without absorption grating and ... An x-ray scintillator screen with a special structure, functioning as detector and analyser grating, was proposed for collecting the interferogram of differential phase contrast imaging without absorption grating and difficulty of fabrication by a state of the art technique. On the basis of phase grating diffraction, a detecting model of the scintillator screen was built for analysing the phase and absorption information of objects. According to the analysis, a new method of phase retrievals based on two-images and the optimal structure of screen were presented. 展开更多
关键词 differential phase contrast x-ray scintillator screen phase retrieval
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Apium graveolens L. accelerating differentiation of neural stem cells in vitro
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作者 文铁桥 陆伟 +3 位作者 陈付学 宋红生 赵翠萍 余涛 《Journal of Shanghai University(English Edition)》 CAS 2006年第1期89-94,共6页
To evaluate the action of Apium graveolens L. on the growth and differentiation of neural stem cells (NSCs), cells culture and animal experiment were performed. NSCs were isolated from the striatum of SD rat embryo ... To evaluate the action of Apium graveolens L. on the growth and differentiation of neural stem cells (NSCs), cells culture and animal experiment were performed. NSCs were isolated from the striatum of SD rat embryo were cultured in the medium containing aqueous extract from Apium graveolens L(AAG).and/or the serum derived from mice treated with Apium graveolens L (SAG). The results show that AAG promoted the survival and growth of NSCs in low concentration. Apium graveolens L. leaves aqueous extract promoted the proliferation of NSCs in relatively high concentration. SAG significantly accelerated the differentiation of NSCs. 展开更多
关键词 neural stem cells Apium graveolens l. differentiation proliferation.
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Effects of Different Hormone Proportions on Differentiation and Regeneration of Prtmus avium L. Adventitious Buds
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作者 Xuanping HU 《Agricultural Biotechnology》 CAS 2014年第1期40-42,共3页
In order to screen the appropriate culture condition for the differentiation and regeneration of Prtmus avium L. adventitious buds, in this study, the effect of different hormone proportions on differentiation and reg... In order to screen the appropriate culture condition for the differentiation and regeneration of Prtmus avium L. adventitious buds, in this study, the effect of different hormone proportions on differentiation and regeneration of shoot tip explants were investigated using Gisela No. 5 and Gisela No. 6 as experimental materi- als. The results showed that, different hormone proportions had extremely significant effects ( P 〈0.01 ) on the differentiation rate of P. avium adventitious buds; the appropriate hormone proportions for Gisela No. 5 and Gisela No. 6 to induce dedifferentiation of adventitious buds were 6-BA 3.0 mg/L + IBA 0.5 mg/L + KT O. 1 mg/L and 6-BA 1.0 mg/L + IBA 0.5 mg/L + KT 0.2 rag/L, respectively. In addition, different hormone proportions had extremely significant effects (P 〈 0.01 ) on the regeneration coefficient and regeneration rate of P. avium adventitious buds; with the hormone proportion of 6-BA 1.0 mg/L + IBA 1.0 mg/L + KT 0.3mg/L, the number of regenerated adventitious buds reached the maximum for both varieties. 展开更多
关键词 Prtrmus avium l. Hormone proportions Adventitious buds differentiation
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Hormonal changes play important roles in the key period of superior and inferior earshoot differentiation in maize
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作者 DU Kang ZHAO Wen-qing +4 位作者 ZHOU Zhi-guo SHAO Jing-jing HU Wei KONG Ling-jie WANG You-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第12期3143-3155,共13页
The upper earshoots with higher superiority usually have higher yield potential and higher efficiency.To determine the key period for the asynchronous differentiation of superior and inferior earshoots and how hormone... The upper earshoots with higher superiority usually have higher yield potential and higher efficiency.To determine the key period for the asynchronous differentiation of superior and inferior earshoots and how hormones are involved in this process,a two-year experiment was designed using two maize hybrids:Suyu 41(S41,single-ear hybrid)and AN 101(A101,double-ear hybrid).The results showed that the lag of lower earshoot differentiation was not only caused by the delay of the differentiation starting time but also related to extension of the duration in spikelet differentiation(stageⅡ)and sexual organ formation stage(stageⅣ).From 12 days before silking(DBS),the contents of indole-3-acetic acid(IAA),zeatin riboside(ZR)+zeatin(ZT),and gibberellic acid(GA_(3))in both upper and lower earshoots of the two hybrids increased dramatically and then decreased quickly.ABA slightly increased in the two hybrids and then decreased slowly in S41,while it was maintained at a high level in A101.At 8 DBS,i.e.,the transition period from floret differentiation to sexual organ formation stage,not only the growth of upper-to-lower earshoot difference(ULED),but also the values for ULED of IAA,ZR+ZT and GA_(3)were all significantly higher in S41 than in A101.Furthermore,the upper-to-lower hormone ratios IAA_(U)/AA_(L)and(ZR+ZT)_(U)/(ZR+ZT)_(L)were also much higher in the single-ear hybrid than in the double-ear hybrid,while the GA_(3U)/GA_(3L)and ABA_(U)/ABA_(L)had no significant differences.In addition,the time course of ULED_(hormone)/ULED_(earshoot growth rate)also suggested that the hormones work in different ways in earshoot superiority/inferiority formation.The delayed differentiation of lower ear shoots was conclusively related to the later initiation of differentiation and the longer durations of specific differentiation stages.Compared with the regulating roles of IAA and ZR+ZT in the key period(8 DBS)of superiority/inferiority differentiation,GA_(3) seems to be affected earlier,while ABA contributes little to this process. 展开更多
关键词 maize(Zea mays l.) earshoot plant hormone superior/inferior differentiation
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PROPERTY (X^+) FOR SECOND-ORDER NONLINEAR DIFFERENTIAL EQUATIONS OF GENERALIZED EULER TYPE
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作者 Asadollah AGHAJANI Vahid ROOMI 《Acta Mathematica Scientia》 SCIE CSCD 2013年第5期1398-1406,共9页
In this paper the generalized nonlinear Euler differential equation t^2k(tu')u''+ t(f(u) + k(tu'))u' + g(u) = 0 is considered. Here the functions f(u), g(u) and k(u) satisfy smoothness conditio... In this paper the generalized nonlinear Euler differential equation t^2k(tu')u''+ t(f(u) + k(tu'))u' + g(u) = 0 is considered. Here the functions f(u), g(u) and k(u) satisfy smoothness conditions which guarantee the uniqueness of solutions of initial value problems, however, no conditions of sub(super) linearity are assumed. W'e present some necessary and sufficient conditions and some tests for the equivalent planar system to have or fail to have property (X^+), which is very important for the existence of periodic solutions and oscillation theory. 展开更多
关键词 property x^+) nonlinear differential equations li^nard system
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Alpha-actinin expression at different differentiating time points from temporal lobe cerebral cortex neural stem cells to neuron-like cells using energy dispersive X-ray analysis
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作者 Bo Yu Hua Li +3 位作者 Zhe Du Yang Hong Meng Sang Yuxiu Shi 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第4期265-270,共6页
BACKGROUND: Alpha-actinin ( a -actinin) plays a key role in neuronal growth cone migration during directional differentiation from neural stem cells (NSCs) to neurons. OBJECTIVE: To detect in situ microdistribut... BACKGROUND: Alpha-actinin ( a -actinin) plays a key role in neuronal growth cone migration during directional differentiation from neural stem cells (NSCs) to neurons. OBJECTIVE: To detect in situ microdistribution and quantitative expression of a -actinin during directional differentiation of NSCs to neurons in the temporal lobe cerebral cortex of neonatal rats. DESIGN, TIME AND SETTING: Between January 2006 and December 2008, culture and directional differentiation of NSCs were performed at Department of Histology and Embryology, Preclinical Medical College, China Medical University. Immune electron microscopy was performed at Department of Histology and Embryology and Department of Electron Micrology, Preclinical Medical College, China Medical University. Spectrum analysis was performed at Laboratory of Electron Microscopy, Mental Research Institute, Chinese Academy of Sciences. MATERIALS: Basic fibroblast growth factor, epidermal growth factor, brain-derived nerve growth factor, type-1 insulin like growth factor, and a -actinin antibody were provided by Gibco BRL, USA; rabbit-anti-rat nestin monoclonal antibody, rabbit-anti-rat neuron specific enolase polyclonal antibody, and EDAX-9100 energy dispersive X-ray analysis were provided by PHILIPS Company, Netherlands. METHODS: NSCs, following primary and passage culture, were differentiated with serum culture medium (DMEM/F12 + 10% fetal bovine serum + 2 ng/mL brain-derived nerve growth factor + 2 ng/mL type-1 insulin like growth factor). MAIN OUTCOME MEASURES: Expression of a -actinin in neuron-like cells was quantitatively and qualitatively detected with immunocytochemistry using energy dispersive X-ray analysis. RESULTS: Immunocytochemistry, combined with electron microscopy, indicated that positive α -actinin expression was like a spheroid particle with high electron density. In addition, the expression was gradually concentrated from the nuclear edge to the cytoplasm and expanded into developing neurites, during differentiation of neural stem cells to neurons. Conversely, energy dispersive X-ray analysis indicated that the more mature the neural differentiation was, and the greater the expression of α -actinin. CONCLUSION: The gradual increase of α -actinin expression is related to growth, development, and maturity of differentiated neuron-like cells, in neonatal rat frontal lobe cortex, at different differentiating time points of NSCs to neurons. 展开更多
关键词 energy dispersive x-ray analysis a -actinin neural stem cells directional differentiation NEURONS
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SU(3)_(L)×U(1)_(X)弱电统一模型
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作者 陈凤至 王平 《高能物理与核物理》 CSCD 北大核心 2000年第11期985-990,共6页
研究了一个 SU(3)L× U(1)x弱电统一模型·要求 M2Z1-M2W/cos2w小于实验值,得到了M_(z′)的下限.再利用M_(z′)和M_u(M_v)之间的关系得到Mu(Mv)的下限.进而考虑了由于Z′交换引... 研究了一个 SU(3)L× U(1)x弱电统一模型·要求 M2Z1-M2W/cos2w小于实验值,得到了M_(z′)的下限.再利用M_(z′)和M_u(M_v)之间的关系得到Mu(Mv)的下限.进而考虑了由于Z′交换引起的KL-Ks质量差,并获得了更严格的M_(z′)和M_u(M_v)的下限. 展开更多
关键词 SU(3)_(l)×U(1)_(x)模型 弱电统一模型
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Role of Plain Abdominal X-Ray in the Differential Diagnosis of Common Acute Abdominal Conditions in Children at Olabisi Onabanjo University Teaching Hospital, Sagamu, Ogun State, Nigeria
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作者 Nwokoro Chigbundu Collins Olatunji Ayodeji Anike +4 位作者 Adekanmbi Abiodun Folashade Amosu Lukmon Olusesan Ogundele Olufemi Ibukunolu Olarewaju Olufunke Yetunde Oyelekan Abimbola Adeola 《Open Journal of Radiology》 2023年第3期125-133,共9页
Background: The plain abdominal x-ray is one of the commonly requested investigations in the children emergency room, paediatric surgical ward and neonatal wards. The short interval required to carry out this investig... Background: The plain abdominal x-ray is one of the commonly requested investigations in the children emergency room, paediatric surgical ward and neonatal wards. The short interval required to carry out this investigative procedure and obtain results makes it the first imaging modality used to unravel the different causes of acute abdominal conditions in children. The safety of abdominal x-ray in children makes it attractive for use in paediatric surgical practice as part of routine work-up for undifferentiated acute abdominal conditions and also to diagnose specific causes of acute abdomen in children. Setting: Olabisi Onabanjo University Teaching Hospital, Sagamu, Ogun State. Objectives: Evaluation of the role of plain abdominal x-ray in diagnosing common acute abdominal conditions in children. Materials and method: Patients admitted to the children emergency room, paediatric surgical wards, children’s ward and neonatal ward who had plain abdominal x-ray as part of their diagnostic work-up were included in the study. They were studied prospectively between March 2011 and April 2021. Results: Three Hundred and Ninety-nine patients who had plain abdominal x-rays as part of their diagnostic work-up were studied. Males were 240 while females were 159, a male to female ratio of 1.5:1. The patients were aged between 1 day to 16 years. Differential diagnoses made with plain abdominal x-ray were intestinal obstruction in 298, perforated viscus 69 patients, intra-abdominal masses 13 patients and location of intra-abdominal foreign body 14. Intestinal obstruction cases in which plain abdominal x-ray played a role in their diagnosis and management included the following: intussusception 66, neonatal sepsis 60, malrotation 48, intestinal atresia 42, anorectal malformation 32, hirschsprung’s disease in 30 cases, pyloric stenosis 24, obstructed hernia 22, post-operative adhesions 16 and intestinal helminthiasis 12. Perforated viscus accounted for 69 indications. Out of these indications, perforated gut in intussusception 19, perforated typhoid ileitis was responsible in 13 cases, gut perforation in blunt abdominal trauma 8, perforation in strangulated hernia 11 cases, perforated gut in malrotation 7, ceacal perforation in hirschsprugs disease 6 and colonic perforation in necrotizing enterocolitis 5 cases. Conclusion: Plain abdominal x-ray remains a role to play in the differential diagnosis and management of common paediatric acute abdominal conditions. 展开更多
关键词 PlAIN ABDOMINAl x-RAY differential Diagnosis ACUTE Abdominal Conditions CHIlDREN
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Mixed Monotone Iterative Technique and Boundary Value Problem for a Class of Impulsive Integro-Differential Equations
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作者 支妍妍 陈海波 吕晨辉 《Journal of Donghua University(English Edition)》 EI CAS 2016年第1期46-53,共8页
In this paper,the existence and uniqueness of iterative solutions to the boundary value problems for a class of first order impulsive integro-differential equations were studied. Under a new concept of upper and lower... In this paper,the existence and uniqueness of iterative solutions to the boundary value problems for a class of first order impulsive integro-differential equations were studied. Under a new concept of upper and lower solutions, a new monotone iterative technique on the boundary value problem of integro-differential equations was proposed. The existence and uniqueness of iterative solutions and the error estimation in certain interval were obtained.An example was also given to illustrate the results. 展开更多
关键词 impulsive integro-differential equations l-quasi-upper and lower solutions mixed monotone iterative technique boundary value problem
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氟离子碰撞引起铅原子L壳层X射线产生截面的实验测量 被引量:2
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作者 吕牛 常宏伟 +2 位作者 张艳萍 徐进章 杜树斌 《原子能科学技术》 EI CAS CSCD 北大核心 2011年第3期257-261,共5页
实验测量了20~50MeV的F离子碰撞Pb原子产生的L壳层X射线,研究了Pb的L各支壳层X射线产生截面σ(Ll)、σ(Lα)、σ(Lβ)、σ(Lγ)和σ(Ltot)与入射离子能量的关系。结果显示:在本能区范围内,Pb原子发射L壳层X射线产生截面随入射离子能量... 实验测量了20~50MeV的F离子碰撞Pb原子产生的L壳层X射线,研究了Pb的L各支壳层X射线产生截面σ(Ll)、σ(Lα)、σ(Lβ)、σ(Lγ)和σ(Ltot)与入射离子能量的关系。结果显示:在本能区范围内,Pb原子发射L壳层X射线产生截面随入射离子能量的增加而增加。利用L壳层的辐射跃迁几率、Coster-Kronig跃迁率和L亚壳层的荧光产额将平面波波恩近似(PWBA)和ECPSSR理论计算的电离截面转换为L层X射线产生截面,并与实验结果相比较。结果表明,σ(Ll)、σ(Lα)、σ(Lβ)、σ(Lγ)、σ(Ltot)实验测量值与PWBA理论计算值差别很大,ECPSSR理论计算值与σ(Lα)实验值符合很好,与σ(Ll)、σ(Lβ)的实验值差别较小,但与σ(Lγ)的实验值差别较大。 展开更多
关键词 l壳层x射线 产生截面 平面波波恩近似理论 ECPSSR理论
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用显微注射法建立转bcl-x_l基因小鼠 被引量:8
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作者 肖文伍 王芙蓉 +5 位作者 张苏明 赵浩斌 郑新明 樊俊华 魏庆信 张旻 《中国神经科学杂志》 SCIE CAS CSCD 2002年第3期630-633,共4页
建立转bcl xl基因小鼠 ,继而传代建系 ,用于缺血性脑血管疾病的研究。采用显微注射法 ,将人bcl xl基因注入昆明小白鼠受精卵获得子代鼠 ,然后作PCR ,Southern blot ,mRNA ,Western blot检测以获得阳性鼠。实验中注射受精卵 16 5 4枚 ,... 建立转bcl xl基因小鼠 ,继而传代建系 ,用于缺血性脑血管疾病的研究。采用显微注射法 ,将人bcl xl基因注入昆明小白鼠受精卵获得子代鼠 ,然后作PCR ,Southern blot ,mRNA ,Western blot检测以获得阳性鼠。实验中注射受精卵 16 5 4枚 ,移植卵数 14 4 8枚 ,受体鼠 4 9只 ,怀孕鼠 7只 ,子代鼠 13只 ,整合数 4只并均有表达 ,植入受精卵的存活率 83% ,受精卵的总存活率 0 .78% ,移植鼠的怀孕率 14 .3% ,整合效率 30 .7% ,总有效率为 0 .2 4 %。初步获得了转bcl 展开更多
关键词 显微注射法 转bcl-x1基因 小鼠 脑缺血 动物模型
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氟离子碰撞引起的钽L壳层X射线产生截面测量 被引量:1
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作者 田野 杨治虎 +4 位作者 张艳萍 常宏伟 杨浩智 徐进章 杜树斌 《原子能科学技术》 EI CAS CSCD 北大核心 2009年第5期406-411,共6页
测量了20~55 MeV F^5+离子和Ta原子碰撞中Ta产生的L壳层X射线。计算了Ta的L各支壳层产生截面的比值和总截面的比值。利用L壳层的辐射跃迁几率、Croster-Kroning跃迁几率和L亚壳层的荧光产额,将平面波波恩近似(PWBA)和ECPSSR理论计... 测量了20~55 MeV F^5+离子和Ta原子碰撞中Ta产生的L壳层X射线。计算了Ta的L各支壳层产生截面的比值和总截面的比值。利用L壳层的辐射跃迁几率、Croster-Kroning跃迁几率和L亚壳层的荧光产额,将平面波波恩近似(PWBA)和ECPSSR理论计算的电离截面转换为L层X射线产生截面,并与实验结果进行比较。结果表明,σ(Ll)/σ(Lα)、σ(Lγ)/σ(Lα)和σ(Ltotal)/σ(Lα)与ECPSSR理论预测结果吻合较好,σ(Lβ)/σ(Lα)较两种理论预测值均偏小。 展开更多
关键词 平面波波恩近似 ECPSSR理论 产生截面 l壳层x射线
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X .ampelina TS206发酵制备冰核活性蛋白的研究 被引量:8
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作者 刘健 陈庆森 +3 位作者 阎亚丽 王启明 宋丽萍 张群 《生物技术》 CAS CSCD 2002年第6期33-34,共2页
优化XanthomonasampelinaTS2 0 6的发酵制备条件可以提高冰核活性和生物量。通过摇瓶培养对该菌进行培养基成分和温度的筛选。实验结果表明 :( 1 )鱼蛋白胨和乳糖的浓度对冰核活性的提高产生显著影响程度 ,玉米浆影响程度较小 ;( 2 )生... 优化XanthomonasampelinaTS2 0 6的发酵制备条件可以提高冰核活性和生物量。通过摇瓶培养对该菌进行培养基成分和温度的筛选。实验结果表明 :( 1 )鱼蛋白胨和乳糖的浓度对冰核活性的提高产生显著影响程度 ,玉米浆影响程度较小 ;( 2 )生物量影响程度大小的顺序依次为鱼蛋白胨 >乳糖 >甘油 >玉米浆。优化的发酵培养基配方为 :酵母粉 1 0g L、大豆蛋白胨 1 0g L、硫酸镁 0 .5g L、蔗糖 2 0g L、鱼蛋白胨 1 5g L、乳糖 1g L、甘油 2 0g L、玉米浆 1 0g L ,pH 7.0。其较优的发酵温度为 1 8℃ ,发酵时间为4 8h ,能获得较高的冰核活性和生物量。 展开更多
关键词 乳糖1g/l 冰核活性细菌 x.ampelinaTS206 发酵制备 冰核活性蛋白
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