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Apriori and N-gram Based Chinese Text Feature Extraction Method 被引量:4
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作者 王晔 黄上腾 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第4期11-14,20,共5页
A feature extraction, which means extracting the representative words from a text, is an important issue in text mining field. This paper presented a new Apriori and N-gram based Chinese text feature extraction method... A feature extraction, which means extracting the representative words from a text, is an important issue in text mining field. This paper presented a new Apriori and N-gram based Chinese text feature extraction method, and analyzed its correctness and performance. Our method solves the question that the exist extraction methods cannot find the frequent words with arbitrary length in Chinese texts. The experimental results show this method is feasible. 展开更多
关键词 Apriori algorithm n-gram Chinese words segmentation feature extraction
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Extraction Optimization of Polysaccharides from Pitaya Stems 被引量:4
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作者 HE Cong-fen LI Peng +3 位作者 ZHAO Hua SONG Li-ya ZHU Jun DONG Yin-mao 《Agricultural Science & Technology》 CAS 2011年第7期947-949,979,共4页
[Objective]The aim was to describe the extraction of polysaccharides from pitaya stems.[Method]The hot water,enzyme-assisted and microwave-assisted methods were used,with the microwave-assisted extraction being deemed... [Objective]The aim was to describe the extraction of polysaccharides from pitaya stems.[Method]The hot water,enzyme-assisted and microwave-assisted methods were used,with the microwave-assisted extraction being deemed optimal by general evaluation.[Result]The main factors affecting the yield of polysaccharides in the microwave-assisted extraction,by order of magnitude,were as follows:time >microwave power >temperature;additionally,optimal conditions included a 10 min extraction time,an 80℃ extraction temperature and a microwave setting of 200 W.Using these optimal conditions,the yield of PSPS(Polysaccharides from Pitaya Stems) was 1.42%.After purification,the yield of PSPS was 0.74%.[Conclusion]The PSPS was analyzed by IR,MALDI-TOF-MS and an element analysis technique.It was shown to be a polysaccharide mixture,and the molecular weight was between 3 900 and 4 300 Da. 展开更多
关键词 stem of pitaya POLYSACCHARIDE extraction Process optimization Structure identification
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Effect of spinal cord extracts after spinal cord injury on proliferation of rat embryonic neural stem cells and Notch signal pathway in vitro 被引量:9
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作者 Qing-Zhong Zhou Ge Zhang +6 位作者 Hai-Bo Long Fei Lei Fei Ye Xu-Feng Jia Yun-Long Zhou Jian-Ping Kang Da-Xiong Feng 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第7期562-567,共6页
Objective:To investigate the effect of the spinal cord extracts(SCE)after spinal cord injuries(SCIs)on the proliferation of rat embryonic neural stem cells(NSCs)and the expressions of mRNA of Notch1 as well as of Hes1... Objective:To investigate the effect of the spinal cord extracts(SCE)after spinal cord injuries(SCIs)on the proliferation of rat embryonic neural stem cells(NSCs)and the expressions of mRNA of Notch1 as well as of Hes1 in this process in vitro.Methods:The experiment was conducted in 4 different mediums:NSCs+PBS(Group A-blank control group),NSCs+SCE with healthy SD rats(Croup B-normal control group),NSCs+SCE with SD rats receiving sham-operation treatment(Croup C-sham-operation group)and NSCs+SCE with SCIs rats(Group D-paraplegic group).Proliferative abilities of 4 different groups were analyzed by MTT chromatometry after co-culture for 1,2,3,4 and 5 d,respectively.The expressions of Notch 1 and Hes1 mRNA were also detected with RT-PCR after co-culture for 24 and 48 h,respectively.Results:After co-culture for 1,2,3,4 and 5 d respectively,the MTT values of group D were significantly higher than those of group A,group B and group C(P<0.05).However,there were no significantly differences regarding MTT values between group A,group B and group C after co-culture for 1,2,3,4 and 5 d,respectively(P>0.05).Both the expressions of Notch1 and Hes1 mRNA of group D were significantly higher than those of other 3 groups after co-culture for 24 h and 48 h as well(P<0.05).But there was no difference oin expressions of Notch1 and Hes1 mRNA among group A,group B and group C after co-culture for 24 h and 48 h(P>0.05).There was no difference in expressions of Notch1and Hes1 mRNA between 24 h and 48 h treatment in group D.Conclusions:SCE could promote the proliferation of NSCs.It is demonstrated that the microenvironment of SCI may promote the proliferation of NSCs.Besides,SCE could increase the expression of Notch1 and Hes1 mRNA of NSC.It can be concluded that the Notch signaling pathway activation is one of the mechanisms that locally injured microenvironment contributes to the proliferation of ENSC after SCIs.This process may be performed by up-regulating the expressions of Notch1 and Hes1 gene. 展开更多
关键词 Neural stem CELL CELL culture Spinal CORD extract NOTCH signal pathway
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Effects of Ginkgo biloba extract EGb761 on neural differentiation of stem cells offer new hope for neurological disease treatment 被引量:6
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作者 Chao Ren Yong-Qiang Ji +5 位作者 Hong Liu Zhe Wang Jia-Hui Wang Cai-Yi Zhang Li-Na Guan Pei-Yuan Yin 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第7期1152-1157,共6页
Stem cell transplantation has brought new hope for the treatment of neurological diseases.The key to stem cell therapy lies in inducing the specific differentiation of stem cells into nerve cells.Because the different... Stem cell transplantation has brought new hope for the treatment of neurological diseases.The key to stem cell therapy lies in inducing the specific differentiation of stem cells into nerve cells.Because the differentiation of stem cells in vitro and in vivo is affected by multiple factors,the final differentiation outcome is strongly associated with the microenvironment in which the stem cells are located.Accordingly,the optimal microenvironment for inducing stem cell differentiation is a hot topic.EGb761 is extracted from the leaves of the Ginkgo biloba tree.It is used worldwide and is becoming one of the focuses of stem cell research.Studies have shown that EGb761 can antagonize oxygen free radicals,stabilize cell membranes,promote neurogenesis and synaptogenesis,increase the level of brain-derived neurotrophic factors,and replicate the environment required during the differentiation of stem cells into nerve cells.This offers the possibility of using EGb761 to induce the differentiation of stem cells,facilitating stem cell transplantation.To provide a comprehensive reference for the future application of EGb761 in stem cell therapy,we reviewed studies investigating the influence of EGb761 on stem cells.These started with the composition and neuropharmacology of EGb761,and eventually led to the finding that EGb761 and some of its important components play important roles in the differentiation of stem cells and the protection of a beneficial microenvironment for stem cell transplantation. 展开更多
关键词 nerve REGENERATION GINKGO biloba extract GINKGOLIDE B traditional Chinese medicine stem cells induction of differentiation stem cell transplantation synaptic plasticity pharmacological effect NEUROLOGICAL diseases nervous systems neural REGENERATION
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A ginkgo biloba extract promotes proliferation of endogenous neural stem cells in vascular dementia rats 被引量:13
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作者 Jiwei Wang Wen Chen Yuliang Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第18期1655-1662,共8页
The ginkgo biloba extract EGb761 improves memory loss and cognitive impairments in patients with senile dementia. It also promotes proliferation of neural stem cells in the subventricular zone in Parkinson's disease ... The ginkgo biloba extract EGb761 improves memory loss and cognitive impairments in patients with senile dementia. It also promotes proliferation of neural stem cells in the subventricular zone in Parkinson's disease model mice and in the hippocampal zone of young epileptic rats. However, it remains unclear whether EGb761 enhances proliferation of endogenous neural stem cells in the brain of rats with vascular dementia. In this study, a vascular dementia model was established by repeatedly clipping and reperfusing the bilateral common carotid arteries of rats in combination with an intraperitoneal injection of a sodium nitroprusside solution. Seven days after establishing the model, rats were intragastrically given EGb761 at 50 mg/kg per day. Learning and memory abilities were assessed using the Morris water maze and proliferation of endogenous neural stem cells in the subventricular zone and dentate gyrus were labeled by 5-bromo-2-deoxyuridine immunofluorescence in all rats at 15 days, and 1, 2, and 4 months after model establishment. The escape latencies in Morris water maze tests of rats with vascular dementia after EGb761 treatment were significantly shorter than the model group. Immunofluorescence staining showed that the number and proliferation of 5-bromo-2-deoxyuridine-positive cells in the subventricular zone and dentate gyrus of the EGb761-treated group were significantly higher than in the model group. These experimental findings suggest that EGb761 enhances proliferation of neural stem cells in the subventricular zone and dentate gyrus, and significantly improves learning and memory in rats with vascular dementia. 展开更多
关键词 neural regeneration traditional Chinese medicine ginkgo biloba extract EGB761 vasculardementia neural stem cells subventricular zone dentate gyrus learning and memory grants-supported paper NEUROREGENERATION
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Preliminary studies of acute and sub-chronic toxicity of the aqueous extract of Guibourtia tessmannii(Harms) J.Leonard stem barks (Caesalpiniaceae) in mice and rats 被引量:2
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作者 Noreen Orianna Koumba Madingou Aristide Traore +4 位作者 Alain Souza Marlaine Michelle Boukandou Mounanga Raissa Reine Aworet Samseny Sylvin Ouedraogo Alfred Sababenedyo Traore 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2016年第6期506-510,共5页
Objective: To investigate the toxicity of aqueous extract of Guibourtia tessmannii(Harms) J. Leonard(G. tessmannii) and evaluate its safety.Methods: NMRI mice were used to determine the acute toxicity of G. tessmannii... Objective: To investigate the toxicity of aqueous extract of Guibourtia tessmannii(Harms) J. Leonard(G. tessmannii) and evaluate its safety.Methods: NMRI mice were used to determine the acute toxicity of G. tessmannii.Increasing concentrations of the plant extracts were administered intraperitoneally or by force-feeding. General behavior and death were monitored and recorded daily for 7 days.In order to determine the sub-acute toxicity of the extract, several doses were administered by oral gavage daily for 28 days in adult Wistar rats. Different parameters were assessed including body weight, food and water intake, biochemical parameters and several vital organ weights.Results: LD50 of 328.78 mg/kg was obtained by i.p. route and more than 5 000 mg/kg was obtained in acute toxicity by oral route. In sub-acute toxicity, no significant alteration was observed in body weight or vital organs, food and water intake, and biochemical parameters.Conclusions: The results showed that the aqueous extract of G. tessmannii has low toxicity intraperitoneally and no sub-acute toxicity via oral intake. 展开更多
关键词 Guibourtia tessmannii stem barks Plant extract HERBAL medicine TOXICITY
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Neuronal-like differentiation of bone marrow-derived mesenchymal stem cells induced by striatal extracts from a rat model of Parkinson's disease 被引量:3
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作者 Xiaoling Qin Wang Han Zhigang Yu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第34期2673-2680,共8页
A rat model of Parkinson's disease was established by 6-hydroxydopamine injection into the medial forebrain bundle. Bone marrow-derived mesenchymal stem cells (BMSCs) were isolated from the femur and tibia, and wer... A rat model of Parkinson's disease was established by 6-hydroxydopamine injection into the medial forebrain bundle. Bone marrow-derived mesenchymal stem cells (BMSCs) were isolated from the femur and tibia, and were co-cultured with 10% and 60% lesioned or intact striatal extracts. The results showed that when exposed to lesioned striatal extracts, BMSCs developed bipolar or multi-polar morphologies, and there was an increase in the percentage of cells that expressed glial fibrillary acidic protein (GFAP), nestin and neuron-specific enolase (NSE). Moreover, the percentage of NSE-positive cells increased with increasing concentrations of lesioned striatal extracts. However, intact striatal extracts only increased the percentage of GFAP-positive cells. The findings suggest that striatal extracts from Parkinson's disease rats induce BMSCs to differentiate into neuronal-like cells in vitro. 展开更多
关键词 bone marrow-derived mesenchymal stem cell Parkinson's disease striatal extract induceddifferentiation nerve cell glial fibrillary acidic protein NESTIN neuron-specific enolase neural stemcell regeneration neural regeneration
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Effects of sargentgloryvine stem extracts on HepG-2 cellsin vitro andin vivo 被引量:3
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作者 Ming-Hua Wang Min Long Bao-Yi Zhu Shu-Hui Yang Ji-Hong Ren Hui-Zhong Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第23期2848-2854,共7页
AIM:To observe the effects of sargentgloryvine stem extracts (SSE) on the hepatoma cell line HepG-2 in vitro andin vivo and determine its mechanisms of action.METHODS:Cultured HepG-2 cells treated with SSE were analys... AIM:To observe the effects of sargentgloryvine stem extracts (SSE) on the hepatoma cell line HepG-2 in vitro andin vivo and determine its mechanisms of action.METHODS:Cultured HepG-2 cells treated with SSE were analysed by 3-(4,5-Dimethyl-thiazol-2-yl)-2,5Diphenyltetrazolium bromide and clone formation assay.The cell cycle and apoptosis analysis were conducted by flow cytometric,TdT-Mediated dUTP Nick End Labeling and acridine orange/ethidium bromide staining methods,and protein expression was examined by both reverse transcriptase-polymerase chain reaction and Western blotting.The pathological changes of the tumor cells were observed by haematoxylin and eosin staining.Tumor growth inhibition and side effects were determined in a xenograft mouse model.RESULTS:SSE treatment could not only inhibit HepG-2 cell proliferation in a doseand time-dependent manner but also induce apoptosis and cell cycle arrest at the S phase.The number of colonies formed by SSEtreated tumor cells was fewer than that of the controls (P<0.05).SSE induced caspase-dependent apoptosis accompanied by a significant decrease in Bcl-xl and Mcl-1 and elevation of Bak expression (P<0.05).Tumor necrosis factor α in the xenograft tumor tissue and the liver functions of SSE-treated mice showed no significant changes at week 8 compared with the control group (P>0.05).Systemic administration of SSE could inhibit the HepG-2 xenograft tumor growth with no obvious toxic side effects on normal tissues.CONCLUSION:SSE can induce apoptosis of HepG-2 cells in vitro and in vivo through decreasing expression of Bcl-xl and Mcl-1 and increasing expression of Bax. 展开更多
关键词 Sargentgloryvine stem extract Apoptosis Human hepatocellular carcinoma HEPG-2 Bcl-2 family
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Improvement of Atrophic Acne Scar and Skin Complexity by Combination of Aqueous Human Placenta Extract and Mesenchymal Stem Cell Mesotherapy 被引量:2
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作者 Ruchee Phonchai Pimjai Naigowit +3 位作者 Bunchob Ubonsaen Supansa Nilubol Supaluk Brameld Parinya Noisa 《Journal of Cosmetics, Dermatological Sciences and Applications》 2020年第1期1-7,共7页
Atrophic scars, a permanent complication of severe acne, have negative effect on psychology in adolescent. The treatment of atrophic scar is depended on types of scar and it is difficult to improve by a single treatme... Atrophic scars, a permanent complication of severe acne, have negative effect on psychology in adolescent. The treatment of atrophic scar is depended on types of scar and it is difficult to improve by a single treatment. Mesenchymal stem cell is a scientific approval for surgery scar treatment and wound healing. We present a case report of female presented with atrophic acne scar distributed on both cheeks. The case aims to prove that the combination of MSCs and aqueous human placenta extract (RGF&#174) contained bioactive therapeutic molecules obviously promoted the improvement of skin scar to reach the optimal outcomes. We first found that MSCs-contained human placenta extract solution combination subcision improves the atrophic acne scar and skin complexity by enhancement of skin cell regeneration. 展开更多
关键词 ATROPHIC Scar Mesenchymal stem Cells Human PLACENTA extract MESOTHERAPY SKIN Regeneration
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Study on the Antioxidant Activity of Grape Stems (<i>Vitis vinifera</i>). A Preliminary Assessment of Crude Extracts
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作者 Antonia Llobera 《Food and Nutrition Sciences》 2012年第4期500-504,共5页
The antioxidant activity of 80% ethanol and 70% acetone extracts of stems from red and white grapes (Vitis vinifera) used in wine industry were evaluated to determine their feasibility as natural antioxidants. The res... The antioxidant activity of 80% ethanol and 70% acetone extracts of stems from red and white grapes (Vitis vinifera) used in wine industry were evaluated to determine their feasibility as natural antioxidants. The results showed that all grape stem extracts were rich in total polyphenolic compounds and flavanols and had clear antioxidant activities. The free radical-scavenging capacity of the extracts was determined using the DPPH (2,2-diphenyl-1-picrylhydrazyl) method. The extracts obtained from red grape stem present EC50 values of 0.14 g dm/g DPPH (acetone extract) and 0.20 g dm/g DPPH (ethanol extract) while the extracts obtained from white grape stem present EC50 values of 0.26 g dm/g DPPH (acetone extract) and 0.37 g dm/g DPPH (ethanol extract). There are significant correlations between the total content of polyphenols and the antioxidant activity (R2 = 0.9352) and between the flavanols content and the antioxidant activity (R2 = 0.9404) of the grape stem extracts obtained. 展开更多
关键词 GRAPE stem Antioxidant ACTIVITY stem extracts Polyphenols Radical Scavenging ACTIVITY DPPH
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Antibacterial Activity of Psidium guajava Leaf and Stem Bark Extracts on Selected Bacteria in Ugbokolo, Benue State, Nigeria
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作者 Peter Adikwu Emmanuel Godwin Oyiwona +4 位作者 Adejor Johnson Yuana Awua Amina Ojochide Hassan Terkaa Oluwakemisola Adenugba Ene Theresa Ebiega 《Advances in Microbiology》 CAS 2022年第10期569-578,共10页
Aim: In recent years, there has been a growing interest in researching and developing new antimicrobial agents from various sources to combat microbial resistance. The study was aimed at determining the phytochemical ... Aim: In recent years, there has been a growing interest in researching and developing new antimicrobial agents from various sources to combat microbial resistance. The study was aimed at determining the phytochemical constituents and in vitro antibacterial activity of methanol and aqueous extracts of Psidium guajava leaves and stem bark on Escherichia coli, Salmonella typhi, Staphylococcus aureus and Proteus sp. in Ugbokolo, Nigeria. Materials and Methods: The phytochemical screening of the plant materials for various bioactive components was conducted between July and December, 2019 using standard laboratory techniques. The extracts were purified using column chromatography. The identity of the test isolates were confirmed using morphological characteristics, gram stain, motility and appropriate biochemical tests such as indole, catalase, coagulase, triple sugar iron agar. The susceptibility of the isolates to each bioactive component was determined using the agar well diffusion method. The broth dilution method was employed for the determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts. Results: The result of the study showed the presence of phenol, tannins, flavonoids and saponins as bioactive compounds. The antibacterial susceptibility of the isolates to aqueous and methanol extracts of leaf and stem bark of Psidium guajava varied significantly (P Staphylococcus aureus was the most susceptible isolate at 200 mg/ml concentration with average zone of inhibition of 13.05 mm for leaf extract and 15.34 mm for stem bark extract. Proteus sp. is the least susceptible with average zone of inhibition of 8.88 mm for the leaf extract and 12.36 mm for the stem bark extract respectively. Minimum Inhibitory Concentration and Minimum Bactericidal Concentration of aqueous and methanol extract of P. guajava leaf and stem bark showed that dilutions of various concentrations of aqueous and methanol extracts can inhibit and/or kill the isolates. Lower MIC (3.125 mg/ml) was shown by methanol extract than aqueous extract. MBC of methanol extract ranges between 6.25 - 25.0 mg/ml. Statistical analysis of the result showed methanol extract is more effective than aqueous extract while the stem bark of the plant showed higher efficacy than the leaf. Conclusion: The findings of the study imply that the extract of Psidium guajava has shown promising properties against tested microorganisms. Further study of the extract is therefore recommended. 展开更多
关键词 ANTIBACTERIAL Psidium guajava Leaf extract stem Bark extract
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Activation of bone marrow stem cells colonies by aintake of isoflavone aglycone-rich fermented soybean extract (IFA-FSE) in mice
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《中国输血杂志》 CAS CSCD 2001年第S1期413-,共1页
关键词 bone IFA-FSE in mice Activation of bone marrow stem cells colonies by aintake of isoflavone aglycone-rich fermented soybean extract stem
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黄芪茎叶提取物对仔猪生长性能、养分表观消化率及免疫指标的影响
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作者 刘燕 蒋明琴 李进杰 《中国饲料》 北大核心 2024年第4期41-44,共4页
文章旨在探究添加不同水平黄芪茎叶提取物对断奶仔猪生长性能、养分表观消化率及免疫机能的影响。试验将120头健康的体重(25±0.5)kg的“杜×长×大”三元杂交仔猪随机分成4组,每组3个重复,每个重复组10头,试验分别在基础... 文章旨在探究添加不同水平黄芪茎叶提取物对断奶仔猪生长性能、养分表观消化率及免疫机能的影响。试验将120头健康的体重(25±0.5)kg的“杜×长×大”三元杂交仔猪随机分成4组,每组3个重复,每个重复组10头,试验分别在基础日粮中添加0(1组)、1.0%(2组)、1.5%(3组)、2.0%(4组)黄芪茎叶提取物,预饲期10d,整个试验为期56d。结果表明:(1)试验3、4组平均日增重较1组分别显著提高11.6%、10.1%(P <0.05),其料重比较1组分别显著降低9.4%、7.0%(P <0.05);(2)试验3、4组粪便中的粗蛋白质、粗脂肪、粗纤维的养分表观消化率较1组分别显著提高10.9%、10.8%、10.8%、11.2%、16.5%、15.9%(P <0.05);(3)试验3、4组血清中IgA、IgG、IL-2含量较1组分别显著提高10.8%、11.7%、12.0%、13.7%、22.9%、25.1%(P <0.05),其血清中TNF-α含量较1组分别显著降低20.8%、22.1%(P <0.05)。综上所述,添加1.5%黄芪茎叶提取物可以提高“杜×长×大”二元杂交仔猪的生长性能、养分表观消化率及免疫机能。 展开更多
关键词 黄芪茎叶提取物 仔猪 生长性能 养分表观消化率 免疫机能
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椰子半腐烂茎干提取物对二疣犀甲聚集信息素增效作用研究
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作者 吕朝军 钟宝珠 +1 位作者 李文天 袁伟钦 《热带农业科学》 2024年第1期18-22,共5页
为提高二疣犀甲聚集信息素的使用效率,为该虫的物理防治策略制定提供参考,对二疣犀甲的非成虫期发育场所进行了调查,并研究了椰子半腐烂茎干提取物与二疣犀甲聚集信息素的协同应用效果。结果显示:共在8种场所发现二疣犀甲的不同虫态,包... 为提高二疣犀甲聚集信息素的使用效率,为该虫的物理防治策略制定提供参考,对二疣犀甲的非成虫期发育场所进行了调查,并研究了椰子半腐烂茎干提取物与二疣犀甲聚集信息素的协同应用效果。结果显示:共在8种场所发现二疣犀甲的不同虫态,包括棕榈茎干腐烂物、锯末堆、椰糠和粪肥混合物等;以椰子半腐烂茎干为提取原料,供试溶剂中以甲醇和乙醇对浸提物的提取率最高,分别为13.11%和11.66%,采用水蒸气蒸馏法对挥发物提取率为0.03%;不同溶剂浸提物处理中,以石油醚浸提物诱集到的虫口数量较多,为3.33头;挥发物平均诱集虫数为8.67头;添加挥发物后,显著增加了二疣犀甲聚集信息素对成虫的诱集总量,增效率为45.83%;添加浸提物和挥发物均显著增加了信息素对二疣犀甲雌虫的诱集效果。本研究结果可为二疣犀甲聚集信息素的高效利用及相关增效产品的研发提供参考。 展开更多
关键词 二疣犀甲 椰子半腐烂茎干提取物 聚集信息素 增效作用
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西番莲茎叶提取物对热应激下蛋鸡产蛋性能、蛋品质和抗氧化性能的影响研究
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作者 刘磊 卢冰霞 +5 位作者 莫红芳 莫文湛 蒙翠萍 吴健平 蒋玲艳 彭健波 《饲料工业》 CAS 北大核心 2024年第21期68-73,共6页
试验旨在了解西番莲茎叶提取物对夏季热应激下蛋鸡产蛋性能、蛋品质和抗氧化性能的影响。试验于夏季选取210日龄海兰褐蛋鸡240只,随机分为对照组、低剂量组、中剂量组和高剂量组4组,对照组饲喂基础日粮,低、中、高剂量组分别在基础日粮... 试验旨在了解西番莲茎叶提取物对夏季热应激下蛋鸡产蛋性能、蛋品质和抗氧化性能的影响。试验于夏季选取210日龄海兰褐蛋鸡240只,随机分为对照组、低剂量组、中剂量组和高剂量组4组,对照组饲喂基础日粮,低、中、高剂量组分别在基础日粮中添加250、500、1000 mg/kg的西番莲茎叶提取物,试验期42 d。结果显示,低、中、高剂量组蛋重均显著高于对照组(P<0.05),高剂量组产蛋率显著高于对照组(P<0.05),高、中剂量组平均日采食量显著高于对照组(P<0.05),高剂量组料蛋比显著低于对照组(P<0.05)。高、中剂量组鸡蛋的蛋白高度和哈夫单位显著高于对照组(P<0.05),高剂量组鸡蛋的蛋壳厚度显著高于对照组(P<0.05);各组蛋黄重、蛋黄比例、蛋形指数和蛋黄颜色无显著差异(P>0.05)。高、中剂量组血清中谷胱甘肽过氧化物酶活性显著高于对照组(P<0.05);低、中、高剂量组血清中丙二醛(MDA)含量显著低于对照组(P<0.05);各组间血清中超氧化物歧化酶、总抗氧化能力和过氧化氢酶活性差异不显著(P>0.05)。说明西番莲茎叶提取物可提高夏季热应激条件下海兰褐蛋鸡产蛋性能、蛋品质和抗氧化性能。 展开更多
关键词 西番莲茎叶提取物 蛋鸡 产蛋性能 蛋品质 抗氧化性能
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干酪乳杆菌发酵人参茎叶提取物对锦鲫免疫及抗氧化功能的影响 被引量:1
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作者 孟欣 于鹏 +1 位作者 单晓枫 钱爱东 《水产学报》 CAS CSCD 北大核心 2024年第2期117-130,共14页
为了研究干酪乳杆菌发酵人参茎叶提取物对锦鲫的免疫及抗氧化功能的影响,实验先用3%、4%、5%、6%(记为L3、L4、L5、L6)的干酪乳杆菌菌液发酵人参茎叶提取物,再分别添加到基础饲料(记为L0)中,对初始平均体重为(25.00±0.05)g的锦鲫... 为了研究干酪乳杆菌发酵人参茎叶提取物对锦鲫的免疫及抗氧化功能的影响,实验先用3%、4%、5%、6%(记为L3、L4、L5、L6)的干酪乳杆菌菌液发酵人参茎叶提取物,再分别添加到基础饲料(记为L0)中,对初始平均体重为(25.00±0.05)g的锦鲫进行为期5周的饲喂实验。周期性取样,采集锦鲫血清、肝胰脏、中肾、脾脏和全肠,以检测相关免疫指标的变化。在饲喂实验结束后进行嗜水气单胞菌攻毒保护性实验。结果显示,与L0组相比,L5组碱性磷酸酶(AKP)、免疫球蛋白M(IgM)、溶菌酶(LZM)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)含量显著升高,L5组丙二醛(MDA)含量显著低于L0组。各组织中IL-10、TNF-α、TGF-β、IFN-γ、IL-1β基因表达水平均有不同程度的升高,表现出时空差异,其中IL-10的基因水平表达升高更为敏感。在攻毒保护性实验中,L5组的存活率达到30%,相较于其他组而言存活率最高。研究表明,本实验条件下,当干酪乳杆菌的接种量为5%时,人参茎叶提取物发酵对锦鲫的应用效果最好,能够提高锦鲫抗氧化能力及免疫相关基因的表达,并对降低嗜水气单胞菌的感染有较好的预防作用。 展开更多
关键词 锦鲫 人参茎叶提取物 干酪乳杆菌 嗜水气单胞菌 抗氧化 免疫调节
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三七茎叶提取物对断奶仔猪生长性能、血清生化指标和肠道健康的影响 被引量:2
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作者 邬昆富 王悦 +1 位作者 谢艺理 吴苗苗 《饲料研究》 CAS 北大核心 2024年第6期26-30,共5页
试验旨在研究三七茎叶提取物对断奶仔猪生长性能、血清生化指标和肠道健康的影响。选取26日龄断奶仔猪24头随机分为3组,每组8个重复,每个重复1头仔猪。对照组饲喂基础饲粮,低剂量组、高剂量组分别在基础饲粮中添加0.2%和0.4%的三七茎叶... 试验旨在研究三七茎叶提取物对断奶仔猪生长性能、血清生化指标和肠道健康的影响。选取26日龄断奶仔猪24头随机分为3组,每组8个重复,每个重复1头仔猪。对照组饲喂基础饲粮,低剂量组、高剂量组分别在基础饲粮中添加0.2%和0.4%的三七茎叶提取物。试验期21 d。结果显示,与对照组相比,高剂量组断奶仔猪平均日增重显著升高(P<0.05),低剂量组和高剂量组血清乳酸脱氢酶活性、谷草转氨酶活性和谷草/谷丙的比值显著降低(P<0.05);高剂量组断奶仔猪十二指肠、空肠、回肠的绒毛高度显著增加(P<0.05),十二指肠和回肠的绒隐比显著升高(P<0.05);低剂量组和高剂量组结肠白细胞介素-12 p35(IL-12 p35)、白细胞介素-12 p40(IL-12 p40)、肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)和干扰素-γ(IFN-γ)的mRNA表达量显著降低(P<0.05)。研究表明,在饲粮中添加三七茎叶提取物可以改善断奶仔猪生长性能、肠道健康,添加0.4%三七茎叶提取物较为适宜。 展开更多
关键词 三七茎叶提取物 断奶仔猪 生长性能 血清生化 肠道健康
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槐角提取物对颌骨骨髓间充质干细胞成骨向分化的影响 被引量:1
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作者 林惠 高云飞 +1 位作者 刘晶 马旭辉 《中国口腔颌面外科杂志》 CAS 2024年第1期23-28,共6页
目的 :探讨槐角提取物对颌骨骨髓间充质干细胞(jaw bone marrow mesenchymal stem cells,jBMSCs)成骨分化的影响。方法:采用CCK-8法检测10、25、50、100μmol/L槐角提取物溶液对jBMSCs增殖的影响,采用BCIP/NBT碱性磷酸酯酶显色、茜素红... 目的 :探讨槐角提取物对颌骨骨髓间充质干细胞(jaw bone marrow mesenchymal stem cells,jBMSCs)成骨分化的影响。方法:采用CCK-8法检测10、25、50、100μmol/L槐角提取物溶液对jBMSCs增殖的影响,采用BCIP/NBT碱性磷酸酯酶显色、茜素红染色检测10、25、50μmol/L槐角提取物溶液对jBMSCs成骨分化水平的影响,采用蛋白免疫印迹试验(Western blot)和实时定量荧光PCR检测槐角提取物溶液对jBMSCs成骨分化相关分子的蛋白和mRNA表达水平的影响。采用GraphPad Prism 9软件包对数据进行统计学分析。结果:100μmol/L槐角提取物溶液对jBMSCs有明显毒性作用(P<0.0001),10、25和50μmol/L浓度不影响细胞增殖(P>0.05)。与对照组相比,10、25和50μmol/L组的碱性磷酸酶活性、钙结节数量、成骨分化相关分子的蛋白和mRNA表达水平均逐渐升高。结论:10、25、50μmol/L浓度的槐角提取物能促进jBMSCs成骨向分化。 展开更多
关键词 槐角提取物 颌骨骨髓间充质干细胞 成骨向分化 细胞增殖
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黄芩茎叶葡萄糖醛酸水解酶提取工艺、酶学性质、实际应用研究
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作者 程雨婕 陈旭 +4 位作者 刘云华 黄志芳 陈燕 刘玉红 易进海 《中成药》 CAS CSCD 北大核心 2024年第1期35-40,共6页
目的研究黄芩茎叶葡萄糖醛酸水解酶(sbslGUS)提取工艺、酶学性质、实际应用。方法在单因素试验基础上,以粒度、加水量、提取时间、提取次数为影响因素,酶活性为评价指标,正交试验优化提取工艺。分析底物(黄芩苷)浓度与酶解速度的关系,计... 目的研究黄芩茎叶葡萄糖醛酸水解酶(sbslGUS)提取工艺、酶学性质、实际应用。方法在单因素试验基础上,以粒度、加水量、提取时间、提取次数为影响因素,酶活性为评价指标,正交试验优化提取工艺。分析底物(黄芩苷)浓度与酶解速度的关系,计算V_(max)、K_(m),考察pH值、温度、金属离子对酶活性的影响,评价pH稳定性、热稳定性。sbslGUS酶解黄芩苷以制备黄芩素,考察pH值、温度、反应时间、底物初始浓度、加酶量对转化率的影响。结果最优提取工艺为粒度40目,加水量10倍,提取时间15 min,提取次数3次。酶解符合酶促反应动力学,K_(m)为0.0063 mol/L,V_(max)为70.42μmol/h,在pH值6.0、温度45℃、金属离子100 mmol/L Cu2+下酶活性最强,sbslGUS在pH值4.0~7.0、温度4~30℃范围内稳定性良好。最优制备工艺为pH值6.0,温度45℃,反应时间12 h以上,底物初始浓度67.2 mmol/L,加酶量1 mL/0.269 mmol黄芩苷,转化率为97.83%。结论sbslGUS酶解效率高,条件温和,可为获取黄芩素提供简便的制备方法,并且拓展了黄芩茎叶应用途径。 展开更多
关键词 黄芩茎叶 葡萄糖醛酸水解酶 提取工艺 酶学性质 实际应用
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中药及间充质干细胞调控免疫反应治疗肌萎缩侧索硬化症的作用机制 被引量:1
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作者 王绍娜 高晨 +2 位作者 樊飞燕 刘飞祥 张运克 《中国组织工程研究》 CAS 北大核心 2024年第25期4087-4093,共7页
背景:肌萎缩侧索硬化为一种进行性神经退行性疾病,常导致大脑和脊髓神经元死亡。肌萎缩侧索硬化发病机制极为复杂,难治率、死亡率高且目前其治疗药物仅有2种,因此开发新治疗方法以改善患者预后迫在眉睫。目的:综述中药及间充质干细胞调... 背景:肌萎缩侧索硬化为一种进行性神经退行性疾病,常导致大脑和脊髓神经元死亡。肌萎缩侧索硬化发病机制极为复杂,难治率、死亡率高且目前其治疗药物仅有2种,因此开发新治疗方法以改善患者预后迫在眉睫。目的:综述中药及间充质干细胞调控免疫反应治疗肌萎缩侧索硬化的作用机制。方法:以“traditional Chinese medicine,mesenchymal stem cells,ALS,immune response”为英文检索词,以“中药,间充质干细胞,肌萎缩侧索硬化,免疫反应”为中文检索词,检索万方、中国知网、PubMed及Web of Science数据库2010-2023年的相关文献,最终纳入69篇文献进行综述分析。结果与结论:①中药调控免疫反应治疗肌萎缩侧索硬化可总结为5个机制:主要包括冰片和黄芪甲苷等中药促进闭锁小带蛋白1、闭合蛋白5表达重建血液中枢神经系统屏障完整性;复方扶芳藤合剂调节自然杀伤细胞表面受体分子抑制其自身毒性;半枝莲和广藿香等作用补体系统因子抑制其异常激活;雷公藤和钩藤等介导细胞外信号调节激酶1/2衰减诱导型一氧化氮合酶产生而抑制小胶质细胞活化;左归丸、栝蒌根等促进白细胞介素10表达调控T细胞改善免疫环境。②通过现有研究总结了间充质干细胞调控免疫反应治疗肌萎缩侧索硬化可总结为5个机制:减少水通道蛋白4表达和降低内皮型一氧化氮合酶信号传导等方面修复免疫屏障完整性;释放吲哚胺2,3-双加氧酶和前列腺素E2等因子抗自然杀伤细胞毒性;分泌因子H干扰转化酶活性抑制补体系统异常激活;调控CX3CL1/CX3CR1系统轴或分泌转化生长因子β等途径改变小胶质细胞表型抑制其活性;增加白细胞介素10表达或激活STATS磷酸化通路来恢复T细胞功能。③目前中药联合间充质干细胞治疗肌萎缩侧索硬化研究较少,已知的相关研究报道显示,肌萎灵注射液可促进干细胞增殖分化以及补阳还五汤联合骨髓间充质干细胞显著提高血脑屏障完整性,未来还需进一步探讨两者对难治性肌萎缩侧索硬化的协同治疗效果。 展开更多
关键词 肌萎缩侧索硬化 免疫反应 中药 提取物 复方 间充质干细胞 运动神经元 作用机制 信号通路 炎症因子
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