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Antibodies against the C-terminal peptide of rabbit oviductin inhibit mouse early embryo development to pass 2-cell stage 被引量:8
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作者 PAN YONG, ZHENG GU, JIN PING LUO, JUN Ru WANG, JIA KE TSO National Laboratory of Contraceptives and Devices Research, Shanghai Institute of Planned Parenthood Research, 21.40 Xietu Road, Shanghai 200032, China 《Cell Research》 SCIE CAS CSCD 2002年第1期69-78,共10页
A full-length rabbit oviductin cDNA(1909bp) was cloned. It consists of a 5’-UTR of 52bp, an open reading frame (ORF) of 1374bp and a 3’-UTR of 483bp and has more than 80% homology with that of other mammal oviductin... A full-length rabbit oviductin cDNA(1909bp) was cloned. It consists of a 5’-UTR of 52bp, an open reading frame (ORF) of 1374bp and a 3’-UTR of 483bp and has more than 80% homology with that of other mammal oviductins. N-terminal peptide (NTP) (384 residues) and C-terminal peptide (CTP) (73 residues) of deduced protein precursor has about 80% and 50% identity with that of other mammals respectively. Fusion proteins GST-NTP 368(1R-368N)and GST-CTP73 (369F-441A) were expressed and purified. NH2-terminal of CTP sequencing reveals that the purified protein is consistent with the deduced one. In order to study the function of NTP and CTP the mouse anti-NTP and rabbit anti-CTP antisera were prepared. Tissue-specific (skeleton muscle, oviduct, uterus, ovary, liver, heart and brain) analysis indicated that rabbit oviductin was only found in oviduct. The conditioned medium derived from the rabbit oviduct mucosa epithelial cells has a function of overcoming the early embryonic development block of Kunming mous e cultured in vitro. Anti-CTP antiserum could totally inhibit the early embryo development at 2-cell stage cultured in the conditioned culture medium, but anti-NTP antiserum couldn’t. There was a positive relationship between the ratio of early embryos at development block and the dosage of anti-CTP antiserum added in the conditioned culture medium. These results suggest that oviductin has a function not only on fertilization, but also on the release of early embryonic development block, and the later function domain of rabbit oviductin may be situate in its C-terminal. 展开更多
关键词 Rabbit oviductin c-terminal peptide early embryo DEVELOPMENT loss of function.
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Effects of C-terminal amidation and heptapeptide ring on the biological activities and advanced structure of amurin-9KY, a novel antimicrobial peptide identified from the brown frog, Rana kunyuensis 被引量:1
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作者 Fen Zhang Zhi-Lai Guo +3 位作者 Yan Chen Li Li Hai-Ning Yu Yi-Peng Wang 《Zoological Research》 SCIE CAS CSCD 2019年第3期198-204,共7页
Rana kunyuensis is a species of brown frog that lives exclusively on Kunyu Mountain,Yantai,China.In the current study,a 279-bp cDNA sequence encoding a novel antimicrobial peptide (AMP),designated as amurin-9KY,was cl... Rana kunyuensis is a species of brown frog that lives exclusively on Kunyu Mountain,Yantai,China.In the current study,a 279-bp cDNA sequence encoding a novel antimicrobial peptide (AMP),designated as amurin-9KY,was cloned from synthesized double-strand skin cDNA of R.kunyuensis.The amurin-9KY precursor was composed of 62 amino acid (aa) residues,whereas the mature peptide was composed of 14 aa and contained two cysteines forming a C-terminal heptapeptide ring (Rana box domain) and an amidated C-terminus.These structural characters represent a novel amphibian AMP family.Although amurin-9KY exhibited high similarity to the already identified amurin-9AM from R.amurensis,little is known about the structures and activities of amurin-9 family AMPs so far.Therefore,amurin-9KY and its three derivatives (amurin-9KY1-3) were designed and synthesized.The structures and activities were examined to evaluate the influence of C-terminal amidation and the heptapeptide ring on the activities and structure of amurin-9KY..Results indicated that C-terminal amidation was essential for antimicrobial activity,whereas both C-terminal amidation and the heptapeptide ring played roles in the low hemolytic activity.Circular dichroism (CD) spectra showed that the four peptides adopted an α-helical conformation in THF/H2O (v/v 1∶1) solution,but a random coil in aqueous solution.Elimination of the C-terminal heptapeptide ring generated two free cysteine residues with unpaired thiol groups,which greatly increased the concentration-dependent anti-oxidant activity.Scanning electron microscopy (SEM) was also performed to determine the possible bactericidal mechanisms. 展开更多
关键词 Antimicrobial peptides RANA kunyuensis' Amurin-9KY Heptapeptide RING c-terminal AMIDATION STRUCTURE activity relati on ship
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Amyloid precursor-like protein 2 C-terminal fragments upregulate S100A9 gene and protein expression in BV2 cells
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作者 Guangzhe Li Hui Chen +3 位作者 Lin Cheng Rongjie Zhao Junchang Zhao Yanji Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第21期1923-1928,共6页
The murine microglial cell line BV2 has neuroprotective effects, but is toxic to neurons by secret-ing inlfammatory cytokines, and is an important target in the treatment of nerve inlfammation and neurodegenerative di... The murine microglial cell line BV2 has neuroprotective effects, but is toxic to neurons by secret-ing inlfammatory cytokines, and is an important target in the treatment of nerve inlfammation and neurodegenerative diseases. In the present study, we observed the effects of transfecting three amyloid precursor-like protein 2 (APLP2) C-terminal fragments (CTFs; C57, C50 and C31) in the pEGFP-N1 vector on S100A9 expression in BV2 cells. Reverse transcription-PCR, western blot assay and immunocytochemistry revealed that S100A9 protein and mRNA expression was greater in BV2 cells after CTF transfection than after mock transfection with an empty vector. Furthermore, transfection of full-length APLP2-751 resulted in low levels of S100A9 protein ex-pression. Our results show that APLP2-CTFs upregulate S100A9 protein and mRNA expression in BV2 cells, and identify a novel pathway involved in neuronal injury and apoptosis, and repair and protection in Alzheimer’s disease. 展开更多
关键词 nerve regeneration NEURODEGENERATION Alzheimer’s disease APLP2 S100A9 c-terminal fragments amyloid precursor protein BV2 cells Γ-SECRETASE NSFC grant neural regeneration
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Glomerular organization in the antennal lobe of the oriental armyworm Mythimna separata
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作者 Baiwei Ma Qi Chen +5 位作者 Xi Chu Yidong Zuo Jiayu Wang Yi Yang Guirong Wang Bingzhong Ren 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第11期3812-3829,共18页
In insects,the number and specificity of antennal lobe glomeruli often reflect the number and diversity of expressed chemosensory genes,which are linked to its ecological niche and specific olfactory needs.The orienta... In insects,the number and specificity of antennal lobe glomeruli often reflect the number and diversity of expressed chemosensory genes,which are linked to its ecological niche and specific olfactory needs.The oriental armyworm,Mythimna separata,is an important and common lepidopteran pest of cereal crops.Given its reliance on the olfactory system for crucial behaviors,understanding the evolutionary potential of this system requires a thorough characterization of the anatomical structure of the primary olfactory center.Here,we systematically identified all antennal lobe glomeruli of M.separata based on synaptic antibody immunostaining and mass staining of the olfactory sensory neurons.A total of 69 glomeruli were identified in females and 65 in males,and an intuitive nomenclature based on glomerular positions was applied.Our findings uncovered some sex-specific glomeruli in this species.There were ten female-specific glomeruli and three male-specific glomeruli,except for the macroglomerular complex(MGC)units,with a notable observation that the female labial pit organ glomerulus was larger than its male counterpart.Additionally,we identified four antennal-lobe tracts(ALTs)and retrograde labeling from the calyx revealed that all glomeruli were innervated by the medial ALT projection neurons.The comparison of the olfactory system structures between M.separata and sympatric moths supports their evolutionary convergence in noctuid moths.These results collectively lay the foundation for future studies on olfactory processing in M.separata. 展开更多
关键词 antennal lobe GLOMERULUS olfactory sensory neuron projection neuron antennal-lobe tract Mythimna separata
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Cognitive Disorders, Depression and Anxiety in Temporal Lobe Epilepsy: An Overview
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作者 Amina Tani Nawal Adali 《Journal of Biosciences and Medicines》 2024年第3期77-93,共17页
Partial epilepsies, originating in a specific brain region, affect about 60% of adults with epilepsy. Temporal lobe epilepsy (TLE) is the most prevalent subtype within this category, often necessitating surgical inter... Partial epilepsies, originating in a specific brain region, affect about 60% of adults with epilepsy. Temporal lobe epilepsy (TLE) is the most prevalent subtype within this category, often necessitating surgical intervention due to its refractoriness to antiepileptic drugs (AEDs). Hippocampal sclerosis, a common underlying pathology, often exacerbates the severity by introducing cognitive and emotional challenges. This review delves deeper into the cognitive profile of TLE, along with the risk factors for cognitive disorders, depression, and anxiety in this population. 展开更多
关键词 Temporal lobe Epilepsy Cognitive Disorders ANXIETY DEPRESSION
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A Unique Modelling Strategy to Dynamically Simulate the Performance of a Lobe Pump for Industrial Applications
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作者 Deepak Kumar Kanungo Rabiranjan Murmu Harekrushna Sutar 《Advances in Chemical Engineering and Science》 CAS 2024年第2期57-73,共17页
The performance of a newly designed tri-lobe industrial lobe pump of high capacity is simulated by using commercial CFD solver Ansys Fluent. A combination of user-defined-functions and meshing strategies is employed t... The performance of a newly designed tri-lobe industrial lobe pump of high capacity is simulated by using commercial CFD solver Ansys Fluent. A combination of user-defined-functions and meshing strategies is employed to capture the rotation of the lobes. The numerical model is validated by comparing the simulated results with the literature values. The processes of suction, displacement, compression and exhaust are accurately captured in the transient simulation. The fluid pressure value remains in the range of inlet pressure value till the processes of suction and displacement are over. The instantaneous process of compression is accurately captured in the simulation. The movement of a particular working chamber is traced along the gradual degree of lobe’s rotation. At five different degrees of lobe’s rotation, pressure contour plots are reported which clearly shows the pressure values inside the working chamber. Each pressure value inside the working chamber conforms to the particular process in which the working chamber is operating. Finally, the power requirement at the shaft of rotation is estimated from the simulated values. The estimated value of power requirement is 3.61 BHP FHP whereas the same calculated theoretically is 3 BHP FHP. The discrepancy is attributed to the assumption of symmetry of blower along the thickness. 展开更多
关键词 CFD lobe Pump Moving Dynamic Mesh Pressure Fluctuation Transient Simulation
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Temporal lobe malacia as a rare cause of gelastic seizure:A case report
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作者 Yuan-Sheng Liao Li-Li Gao +1 位作者 Min Lin Cheng-Han Wu 《World Journal of Clinical Cases》 SCIE 2024年第20期4440-4445,共6页
BACKGROUND Gelastic seizure(GS)is a rare type of epilepsy that most commonly appears in patients with hypothalamic hamartoma.It is rarely associated with other types of brain damage.This particular type of epilepsy is... BACKGROUND Gelastic seizure(GS)is a rare type of epilepsy that most commonly appears in patients with hypothalamic hamartoma.It is rarely associated with other types of brain damage.This particular type of epilepsy is relatively rare and has few links to other brain lesions.Temporal lobe malacia is mostly caused by cerebral infarction or cerebral hemorrhage,which can lead to seizures.We report a case of GS in a woman with temporal lobe malacia which was reported for the first time in the literature.CASE SUMMARY A 73-year-old female,diagnosed case of GS,presented with repetitive stereotyped laughter a month prior to presentation,happening multiple times daily and with each time lasting for 5-15s.Electroencephalogram displayed a focal seizure seen in the right temporal region.Magnetic resonance imaging head with contrast showed a right temporal lobe malacia.The patient was started on levetiracetam daily.The patient indicated that they had fully recovered and were not experiencing any recurrent or stereotyped laughter during their daily routines.These results remained consistent even after a one-year follow-up period.CONCLUSION GS can be caused by temporal lobe malacia,which is an uncommon but potentially grave condition.The outcome of this present case exhibited the importance of the temporal lobe in the genesis of GS. 展开更多
关键词 EPILEPSY Gelastic seizure Malacia Temporal lobe Cerebral ischemia Case report
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Regulation of specific abnormal calcium signals in the hippocampal CA1 and primary cortex M1 alleviates the progression of temporal lobe epilepsy
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作者 Feng Chen Xi Dong +11 位作者 Zhenhuan Wang Tongrui Wu Liangpeng Wei Yuanyuan Li Kai Zhang Zengguang Ma Chao Tian Jing Li Jingyu Zhao Wei Zhang Aili Liu Hui Shen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期425-433,共9页
Temporal lobe epilepsy is a multifactorial neurological dysfunction syndrome that is refractory,resistant to antiepileptic drugs,and has a high recurrence rate.The pathogenesis of temporal lobe epilepsy is complex and... Temporal lobe epilepsy is a multifactorial neurological dysfunction syndrome that is refractory,resistant to antiepileptic drugs,and has a high recurrence rate.The pathogenesis of temporal lobe epilepsy is complex and is not fully understood.Intracellular calcium dynamics have been implicated in temporal lobe epilepsy.However,the effect of fluctuating calcium activity in CA1 pyramidal neurons on temporal lobe epilepsy is unknown,and no longitudinal studies have investigated calcium activity in pyramidal neurons in the hippocampal CA1 and primary motor cortex M1 of freely moving mice.In this study,we used a multichannel fiber photometry system to continuously record calcium signals in CA1 and M1 during the temporal lobe epilepsy process.We found that calcium signals varied according to the grade of temporal lobe epilepsy episodes.In particular,cortical spreading depression,which has recently been frequently used to represent the continuously and substantially increased calcium signals,was found to correspond to complex and severe behavioral characteristics of temporal lobe epilepsy ranging from gradeⅡto gradeⅤ.However,vigorous calcium oscillations and highly synchronized calcium signals in CA1 and M1 were strongly related to convulsive motor seizures.Chemogenetic inhibition of pyramidal neurons in CA1 significantly attenuated the amplitudes of the calcium signals corresponding to gradeⅠepisodes.In addition,the latency of cortical spreading depression was prolonged,and the above-mentioned abnormal calcium signals in CA1 and M1 were also significantly reduced.Intriguingly,it was possible to rescue the altered intracellular calcium dynamics.Via simultaneous analysis of calcium signals and epileptic behaviors,we found that the progression of temporal lobe epilepsy was alleviated when specific calcium signals were reduced,and that the end-point behaviors of temporal lobe epilepsy were improved.Our results indicate that the calcium dynamic between CA1 and M1 may reflect specific epileptic behaviors corresponding to different grades.Furthermore,the selective regulation of abnormal calcium signals in CA1 pyramidal neurons appears to effectively alleviate temporal lobe epilepsy,thereby providing a potential molecular mechanism for a new temporal lobe epilepsy diagnosis and treatment strategy. 展开更多
关键词 CA^(2+) calcium signals chemogenetic methods HIPPOCAMPUS primary motor cortex pyramidal neurons temporal lobe epilepsy
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Modified hepatic left lateral lobe inversion in laparoscopic proximal gastrectomy: An analysis of 13 cases
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作者 Jian-An Lin Chu-Ying Wu Kai Ye 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第9期2853-2859,共7页
BACKGROUND In laparoscopic proximal gastrectomy(LPG),the prolapse of the hepatic left lateral lobe near the lesser curvature and esophageal hiatus can obstruct the field of vision and operation.Therefore,it is necessa... BACKGROUND In laparoscopic proximal gastrectomy(LPG),the prolapse of the hepatic left lateral lobe near the lesser curvature and esophageal hiatus can obstruct the field of vision and operation.Therefore,it is necessary to retract or obstruct the hepatic left lateral lobe to ensure a clear field of vision.AIM To investigate the safety and clinical efficacy of the modified hepatic left lateral lobe inversion technique for LPG.METHODS A retrospective analysis was conducted on the clinical data of 13 consecutive patients with early-stage upper gastric adenocarcinoma or adenocarcinoma of the esophagogastric junction treated with LPG from January to December 2023 at the Department of Gastrointestinal Surgery,Second Affiliated Hospital of Fujian Medical University.The modified hepatic left lateral lobe inversion technique was used to expose the surgical field in all patients,and short-term outcomes were observed.RESULTS In all 13 patients,the modified hepatic left lateral lobe inversion technique was successful during surgery without the need for re-retraction or alteration of the liver traction method.There were no instances of esophageal hiatus occlusion,eliminating the need for forceps to assist in exposure.There was no occurrence of intraoperative hepatic hemorrhage,hepatic vein injury,or hepatic congestion.No postoperative digestive complications of Clavien-Dindo grade≥II occurred wi-thin 30 days after surgery,except for a single case of pulmonary infection.Some patients experienced increases in alanine aminotransferase and aspartate aminotransferase levels on the first day after surgery,which significantly decreased by the third day and returned to normal by the seventh day after surgery.CONCLUSION The modified hepatic left lateral lobe inversion technique has demonstrated satisfactory results,offering ad-vantages in terms of facilitating surgical procedures,reducing surgical trauma,and protecting the liver. 展开更多
关键词 Hepatic left lateral lobe Inversion technique LAPAROSCOPY Proximal gastrectomy Liver injury
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NUMERICAL INVESTIGATION OF AERODYNAMIC AND MIXING CHARACTERISTICS OF SCARFED LOBED MIXER FOR TURBOFAN ENGINE EXHAUST SYSTEM 被引量:6
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作者 单勇 张靖周 徐亮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第2期130-136,共7页
The flow field and aerodynamic performances for the scarfed lobed forced mixer are studied based on a computational fluid dynamics(CFD) technique. A series of computations are conducted to obtain the effects of the ... The flow field and aerodynamic performances for the scarfed lobed forced mixer are studied based on a computational fluid dynamics(CFD) technique. A series of computations are conducted to obtain the effects of the bypass ratio and the scarf angle on the mixing performance for the scarfed lobed mixer. Results show that the scarfed lobed mixer is reduced in the system weight. Meanwhile, aerodynamic performances are slightly improved compared with the normal lobed mixer. Two reasons for causing the mixing enhancement between the core and the bypass flow are as follows: (1) The stream-wise vortices shed from the training edge of the half/full scarfed lobed mixer earlier is enhanced by about 25%. (2) The mixing augmentation is also associated with the increase of the interface length caused by scarfing. The thermal mixing efficiency is enhanced with the increase of the bypass ratio and the scarfing angle. The scarfed lobed mixer design has no negative effects on the pressure loss. The total pressure recovery coefficient reaches above 0. 935 in various bypass ratios and scarfed angles. As the bypass ratio increases, the total pressure recovery coefficient also increases for the scarfed lobed mixer. 展开更多
关键词 AERODYNAMICS numerical simulation MIXERS scarfed lobed nozzle aerodynamic characteristics
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主轴-刀柄和刀柄-刀具结合面参数对稳定性Lobe图的影响 被引量:1
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作者 王二化 吴波 +1 位作者 胡友民 杨叔子 《机床与液压》 北大核心 2016年第5期9-13,18,共6页
为探索主轴-刀柄和刀柄-刀具结合面参数与立铣加工过程稳定性的关系,以主轴-刀柄和刀柄-刀具结合面参数辨识方法和两自由度立铣加工过程动力学模型为基础,研究了主轴-刀柄,以及刀柄-刀具结合面参数等因素对稳定性Lobe图的影响。结果表明... 为探索主轴-刀柄和刀柄-刀具结合面参数与立铣加工过程稳定性的关系,以主轴-刀柄和刀柄-刀具结合面参数辨识方法和两自由度立铣加工过程动力学模型为基础,研究了主轴-刀柄,以及刀柄-刀具结合面参数等因素对稳定性Lobe图的影响。结果表明:主轴-刀柄和刀柄-刀具结合面的直线刚度对稳定性Lobe图的影响最大,其他结合面参数对稳定性Lobe图均有不同程度的影响;和主轴-刀柄结合面参数相比,刀柄-刀具结合面参数尤其是转动刚度对稳定性Lobe图的影响更大。 展开更多
关键词 立式铣削 结合面 颤振 lobe
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Prevention and Cure of Acute Alcohol Intoxication in Mice by Administration of Compound of Japanese Raisintree Fruit, Lobed Kudzuvine Flower Bud and Lightyellow Sophora Root 被引量:2
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作者 孔玲 李杰 张秀珍 《Agricultural Science & Technology》 CAS 2014年第5期874-876,881,共4页
[Objective] We aimed to investigate the preventive and therapeutical effect of compound of traditional Chinese drugs (Japanese raisintree fruit, lobed kudzuvine flower bud and lightyel ow sophora root) on acute alc... [Objective] We aimed to investigate the preventive and therapeutical effect of compound of traditional Chinese drugs (Japanese raisintree fruit, lobed kudzuvine flower bud and lightyel ow sophora root) on acute alcohol intoxication in mice. [Method] Acute alcohol intoxication was induced by administering alcohol to mice. Three different doses (low, middle and high) of compound of traditional Chinese drugs were administered to mice before and after administering alcohol respectively to investigate the preventive and therapeutical effect of drugs on acute alcohol intox-ication through doing statistical analysis about drunk mice and their sleeping time. The concentration of malondialdehyde (MDA), reduced glutathione (GSH) and triglyc-erides (TG) in liver was also determined to investigate the protective effect of drugs on liver. [Result] The efficacy of compound of traditional Chinese drugs on acute al-cohol intoxication was dose-dependent. High-dose administration decreased the number of drunk mice significantly compared with control group; middle- and high-dose administration reduced the sleeping time of drunk mice and the concentration of MDA and TG in liver tissue; three doses al increased the concentration of GSH. [Conclusion] The compound of Japanese raisintree fruit, lobed kudzuvine flower bud and lightyel ow sophora root had preventive and therapeutical effect on hangover, and it also had certain preventive and therapeutical effect on liver damage caused by alcohol. 展开更多
关键词 Japanese raisintree fruit lobed kudzuvine flower bud Lightyel ow sophora root Acute alcohol intoxication Anti-drunk Sobering effect
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牛乳铁蛋白基因N-lobe的cDNA克隆及毕赤酵母表达载体的构建 被引量:2
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作者 林松涛 张居农 +5 位作者 王亮 史芳芳 李卫华 张钰 吕自力 王安江 《家畜生态学报》 2008年第5期13-18,共6页
以牛乳腺组织总RAN为模板,经RT-PCR得到牛乳铁蛋白基因的N-lobe片段并将其克隆到pGM-T克隆载体上,最后将其连入表达载体pPICZαA中,构建牛乳铁蛋白基因N-lobe的酵母表达载体。结果表明:克隆片段大小为1028bp,与Gen Bank中登录的序列的... 以牛乳腺组织总RAN为模板,经RT-PCR得到牛乳铁蛋白基因的N-lobe片段并将其克隆到pGM-T克隆载体上,最后将其连入表达载体pPICZαA中,构建牛乳铁蛋白基因N-lobe的酵母表达载体。结果表明:克隆片段大小为1028bp,与Gen Bank中登录的序列的相应部位相比,所获牛乳铁蛋白N-lobe cDNA序列的同源性为99.7%;重组表达质粒经酶切和PCR鉴定构建正确,为酵母表达乳铁蛋白基因N-lobe奠定了基础。 展开更多
关键词 乳铁蛋白 N-lobe 表达载体
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机床相对动柔度劣化对稳定性Lobe图的影响分析
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作者 王二化 吴波 +1 位作者 胡友民 杨叔子 《机床与液压》 北大核心 2016年第11期79-83,共5页
在机床各种形式的振动中,再生颤振具有最小的稳定极限切削宽度,换言之,机床抵抗再生颤振的能力最差。品质系数(Coefficient of Merit,COM)是切削力和切削表面法向相对位移之间的交叉频响函数最小负实部的函数,其大小直接反映机床抵抗再... 在机床各种形式的振动中,再生颤振具有最小的稳定极限切削宽度,换言之,机床抵抗再生颤振的能力最差。品质系数(Coefficient of Merit,COM)是切削力和切削表面法向相对位移之间的交叉频响函数最小负实部的函数,其大小直接反映机床抵抗再生颤振的能力。此外,在机床的连续使用过程中,品质系数COM会逐渐减小,进而影响机床再生颤振抗振能力。基于相对激振方法和四自由度立铣加工过程动力学模型,重点分析了机床相对动柔度劣化过程中品质系数COM的变化趋势,以及对加工过程稳定性Lobe图的影响。研究表明:随着机床相对动柔度的劣化,轴向极限切深ap逐渐减小,并有加速递减的趋势,这和机床品质系数的劣化趋势一致。因此,考虑机床相对动柔度对稳定性Lobe图的影响,才能确定更合适的工艺参数,保证切削过程的稳定性,提高加工效率。 展开更多
关键词 相对激振法 相对动柔度 稳定性lobe 品质系数
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数控立铣加工稳定性Lobe图计算方法研究
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作者 孙新国 桂林 《组合机床与自动化加工技术》 北大核心 2015年第9期140-142,共3页
以立式数控铣床为研究对象,以刀尖频响函数预测模型和立铣切削过程动力学模型为基础,建立了立铣切削过程的动力学模型,得到了立铣切削过程稳定性Lobe图解析算法,计算出了立铣切削过程稳定性Lobe图。通过实验和预测稳定性Lobe图,得到他... 以立式数控铣床为研究对象,以刀尖频响函数预测模型和立铣切削过程动力学模型为基础,建立了立铣切削过程的动力学模型,得到了立铣切削过程稳定性Lobe图解析算法,计算出了立铣切削过程稳定性Lobe图。通过实验和预测稳定性Lobe图,得到他们的图形总体趋势一致,说明根据预测稳定性Lobe图选择切削参数,可以保证切削过程的稳定性。为研究主轴-刀柄结合面参数、刀柄-刀具结合面参数、刀具直径、刀具悬伸长度、切入角、切出角、切向切削系数以及径向切削系数等因素对稳定性Lobe图的影响提供了一种计算方法。 展开更多
关键词 数控立铣 lobe 计算 加工稳定性
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Computation and Validation of Parameter Effects on Lobed Mixer-Ejector Performances 被引量:21
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作者 张靖周 单勇 李立国 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2005年第3期193-198,共6页
Three-dimensional numerical computation of the flow fields and pumping performances for the lobed mixer-ejector are conducted using full Navier-Stokes equations. In the computation, the inlet of the primary flow uses ... Three-dimensional numerical computation of the flow fields and pumping performances for the lobed mixer-ejector are conducted using full Navier-Stokes equations. In the computation, the inlet of the primary flow uses the mass flowrate boundary condition. The inlet of the second flow and the outlet of the mixing flow use the pressure boundary condition. Compared with the relative experimental resuits, it is shown that the present calculation is reasonable. And a series of numerical studies is performed to obtain the effects of area ratio and length-to-diameter ratio of mixing duct on pumping coefficient and thermal mixing efficiency of a lobed mixer-ejector. 展开更多
关键词 lobed nozzle EJECTOR MIXER numerical computation
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Prognostic factors in the surgical treatment of caudate lobe hepatocellular carcinoma 被引量:14
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作者 Peng Liu,Jia-Mei Yang,Wen-Yang Niu,Tong Kan,Feng Xie,Dian-Qi Li,Ye Wang,Yan-Ming Zhou,Department of Special Treatment and Liver Transplantation,Eastern Hepatobiliary Surgery Hospital,Second Military Medical University,Shanghai 200438,China Peng Liu,Department of Hepatobiliary Surgery,Navy General Hospital,Beijing 100037,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第9期1123-1128,共6页
AIM:To evaluate the short-and long-term outcomes of liver resection for caudate lobe hepatocellular carcinoma (HCC).METHODS:We retrospectively analyzed 114 consecutive patients with HCC,originating from the caudate lo... AIM:To evaluate the short-and long-term outcomes of liver resection for caudate lobe hepatocellular carcinoma (HCC).METHODS:We retrospectively analyzed 114 consecutive patients with HCC,originating from the caudate lobe,who underwent resection between January 2001 and January 2007.Univariate and multivariate analyses were performed on several clinicopathologic variables to determine the factors affecting long-term outcome and intrahepatic recurrence.RESULTS:Overall mortality and morbidity were 0% and 18%,respectively.After a median follow-up of 31 mo (interquartile range,11-66 mo),tumor recurrence had occurred in 76 patients (66.7%).The 1-,3-,and 5-year disease-free survival rates were 65.7%,38.1%,and 18.4%,respectively.The 1-,3-,and 5-year overall survival rates were 76.1%,54.7%,and 31.8%,respectively.Univariate analysis showed that subsegmental location of the tumor (45.7% vs 16.2%,P=0.01),liver cirrhosis (12.3% vs 47.9%,P=0.03),surgical margin (18.5% vs 54.6%,P=0.04),vascular invasion (37.9% vs 23.2%,P=0.04) and extended caudate resection (42.1% vs 15.4%,P=0.04) were related to poorer long-term survival.Multivariate analysis showed that only subsegmental location of the tumor,liver cirrhosis and surgical margin were significant independent prognostic factors.CONCLUSION:Hepatectomy was an effective treatment for HCC in the caudate lobe.The subsegmental location of the tumor,liver cirrhosis and surgical margin affected long-term survival. 展开更多
关键词 HEPATECTOMY HEPATOCELLULAR CARCINOMA CAUDATE lobe PROGNOSTIC factors
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Impact of Modal Parameters on Milling Process Chatter Stability Lobes 被引量:6
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作者 LI Zhongqun,LIU Qiang (School of Mechanical Engineering and Automation,BeiHang University,Beijing 100083,China) 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S1期190-195,共6页
Modals of the machine/tool and machine/part system are the principal factors affecting the stability of a milling process. Based on the modeling of chatter stability of milling process,the influence of modal parameter... Modals of the machine/tool and machine/part system are the principal factors affecting the stability of a milling process. Based on the modeling of chatter stability of milling process,the influence of modal parameters on chatter stability lobes independently or jointly has been analyzed by simulation. Peak-to-valley specific value,lobe coefficient and the corresponding calculation formula have been put forward. General laws and steps of modal simplification for multimodality system have been summarized. 展开更多
关键词 MILLING process chatter STABILITY lobeS dynamic STIFFNESS MODAL PARAMETER
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Risks faced by donors of right lobe for living donor liver transplantation 被引量:8
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作者 Ran, Shun Wen, Tian-Fu +8 位作者 Yan, Lu-Nan Li, Bo Zeng, Yong Chen, Zhe-Yu Zhang, Yu Liao, Zhi-Xue Liang, Guan-Lin Li, Guo Zhang, Xian-Hua 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2009年第6期581-585,共5页
BACKGROUND: Because of the shortage of deceased donors with livers fit for transplantation, living donor liver transplantation (LDLT) is becoming an attractive alternative. Attention should be paid to the donors, espe... BACKGROUND: Because of the shortage of deceased donors with livers fit for transplantation, living donor liver transplantation (LDLT) is becoming an attractive alternative. Attention should be paid to the donors, especially to those of the right lobe. In this study, we evaluated the risks faced by donors of the right lobe for adult-to-adult LDLT. METHODS: The perioperative data from 105 consecutive living donors of the right lobe performed in West China Hospital from January 2002 to December 2007 were retrospectively studied. Preoperative evaluation included CT, MRCP, and intraoperative cholangiography, showing liver volume, hepatic vasculature and the biliary system. The standard liver volume (SLV) and the ratio of left lobe volume to SLV were calculated. The right lobe grafts were obtained by transecting the liver on the right side of the middle hepatic vein without inflow vascular occlusion, using an ultrasonic dissector. After operation the donors were monitored in the Intensive Care Unit for about three days. Each donor was followed up for at least 6 months. RESULTS: There was no donor mortality. Major complications occurred in 14 donors (13.3%), of whom 3 received conservative treatment, 8 required invasive paracentesis, and 3 required further surgery. All donors were recovered well and resumed their previous occupations. CONCLUSIONS: Donors of the right lobe face low risks. The preoperative evaluation, especially evaluation of the volume of the remnant liver, should be exact. During the operation, the patency of the remnant hepatic vasculature and bile duct must be preserved, and the extent of injury to the remnant liver should be limited as much as possible. The detection and treatment of postoperative complications should be diligently performed. 展开更多
关键词 liver transplantation living donor right lobe RISK safety
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Resection of hepatic caudate lobe hemangioma:experience with 11 patients 被引量:7
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作者 Xu, Li-Ning Huang, Zhi-Qiang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2010年第5期487-491,共5页
BACKGROUND: Caudate lobectomy is now considered to be the most appropriate surgical treatment for benign tumors in the caudate lobe. But how to resect the caudate lobe safely is a major challenge to current liver surg... BACKGROUND: Caudate lobectomy is now considered to be the most appropriate surgical treatment for benign tumors in the caudate lobe. But how to resect the caudate lobe safely is a major challenge to current liver surgery and requires further study. This research aimed to analyze the perioperative factors and explore the surgical technique associated with liver resection in hepatic caudate lobe hemangioma. METHODS: Eleven consecutive patients with symptomatic hepatic hemangiomas undergoing caudate lobectomy from November 1990 to August 2009 at our hospital were investigated retrospectively. All patients were followed up to the present. RESULTS: In this series, 9 were subjected to isolated caudate lobectomy and 2 to additional caudate lobectomy (in addition to left lobe and right lobe resection, respectively). The average maximum diameter of tumors was 9.65+/-4.11 cm. The average operative time was 232.73+/-72.16 minutes. Five of the 11 patients required transfusion of blood or blood products during surgery. Ascites occurred in I patient, pleural effusion in the perioperative period in 1, and multiple organ failure in 1 on the 6th day after operation as a result of massive intraoperative blood loss, who had received multiple transcatheter hepatic arterial embolization preoperatively. The alternating left-right-left approach produced the best results for caudate lobe surgery in most of our cases. All patients who recovered from the operation are living well and asymptomatic. CONCLUSIONS: For large hemangioma of the caudate lobe, surgery is only recommended for symptomatic cases. Caudate lobectomy of hepatic hemangioma can be performed safely, provided it is carried out with optimized perioperative management and innovative surgical technique. 展开更多
关键词 caudate lobe HEMANGIOMA HEPATECTOMY PERIOPERATIVE surgical technique
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