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Effects of Ginkgo biloba extract EGb761 on neural differentiation of stem cells offer new hope for neurological disease treatment 预览
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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 《中国神经再生研究:英文版》 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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Determination of the Content of Kaempferol from Fermented Ginkgo(Ginkgo biloba L.)Leaves 预览
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作者 Dengfeng ZOU Hua ZHU +1 位作者 Bowen JIANG Xiaohua WANG 《农业生物技术:英文版》 CAS 2019年第1期158-161,共4页
[Objectives]This study was conducted to determine kaempferol content in ginkgo(Ginkgo biloba L.)leaves subjected to microbial fermentation.[Methods]Bacillus licheniformis was selected for solid-state fermentation of g... [Objectives]This study was conducted to determine kaempferol content in ginkgo(Ginkgo biloba L.)leaves subjected to microbial fermentation.[Methods]Bacillus licheniformis was selected for solid-state fermentation of ginkgo leaves,and the content of kaempferol in ginkgo leaves was determined by RP-HPLC method.At first,methanol was used to extract flavonoid glycosides,which were then hydrolyzed by hydrochloric acid solution.HPLC was performed with Platisil ODS column C 18(150 mm×4.6 mm,5μm)using mobile phase V methanol∶V water(0.4%phosphoric acid solution)=55∶45 at a flow rate of 1 ml/min,and the eluate was detected with a shimadzu HPLC ultraviolet detector at 360 nm.[Results]With kaempferol as the reference substance,the correlation coefficient was 0.999 2 in the range of 0.001 06-0.016 96 g/L.The content in the fermented product was less than that in the non-fermented product by 28%.[Conclusions]The method is simple,accurate,and is suitable for determination of kaempferol.This study will provide an experimental basis for the development and utilization of ginkgo. 展开更多
关键词 GINKGO biloba L. GINKGO LEAVES Microbial fermentation Content DETERMINATION HPLC KAEMPFEROL
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Extraction Process and Content Determination of Total Flavonoids in Ginkgo( Ginkgo biloba L. ) Leaves 预览
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作者 Dengfeng ZOU Hua ZHU +1 位作者 Binghua QIN Xiaohua WANG 《农业生物技术:英文版》 CAS 2019年第1期171-175,共5页
[Objectives]This study was conducted to study the extraction process and the content determination of flavonoids in ginkgo(Ginkgo biloba L.)leaves.[Methods]Ethanol extraction and methanol extraction of total flavonoid... [Objectives]This study was conducted to study the extraction process and the content determination of flavonoids in ginkgo(Ginkgo biloba L.)leaves.[Methods]Ethanol extraction and methanol extraction of total flavonoids in ginkgo leaves were studied,and the optimal extraction conditions for flavonoids were determined by orthogonal test;and with quercetin as reference substance,total flavonoid content in ginkgo leaves was determined by UV spectrophotometry.[Results]The optimal extraction process was 4 h of Soxhlet extraction with methanol;and the total flavonoid contents had a good linear relation in the range of 0.006 5-0.039 mg/ml(R 2=0.999 9),the average content was stabilized at 1.135%,and the average recovery of the method was 102.0%.[Conclusions]This study selected the optimal extraction process for total flavonoids in ginkgo leaves.The test method is simple with high accuracy and precision,and is suitable for the extraction and determination of total flavonoids in ginkgo leaves. 展开更多
关键词 GINKGO biloba L. TOTAL FLAVONOIDS EXTRACTION process Content determination
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Ginkgo biloba extracts prevent aortic rupture in angiotensin II-infused hypercholesterolemic mice
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作者 Xiao-fang Huang Song-zhao Zhang +4 位作者 Ya-yu You Na Zhang Hong Lu Alan Daugherty Xiao-jie Xie 《中国药理学报:英文版》 SCIE CAS CSCD 2019年第2期192-198,共7页
Abdominal aortic aneurysms (AAAs) are a chronic vascular disease characterized by pathological luminal dilation. Aortic rupture is the fatal consequence of AAAs. Ginkgo biloba extracts (GBEs), a natural herb extract w... Abdominal aortic aneurysms (AAAs) are a chronic vascular disease characterized by pathological luminal dilation. Aortic rupture is the fatal consequence of AAAs. Ginkgo biloba extracts (GBEs), a natural herb extract widely used as food supplements, drugs, and cosmetics, has been reported to suppress development of calcium chloride-induced AAAs in mice. Calcium chloride-induced AAAs do not rupture, while angiotensin II (AngII)-induced AAAs in mice have high rate of aortic rupture, implicating potentially different mechanisms from calcium chloride-induced AAAs. This study aimed to determine whether GBE would improve aortic dilation and rupture rate of AngII-induced AAAs. Male apolipoprotein E (apoE) -/- mice were infused with AngII and administered either GBE or its major active ingredients, flavonoids and ginkgolides, individually or in combination. To determine the effects of GBE in mice with established AAAs, male apoE-/- mice were flrstly infused with AngII for 28 days to develop AAAs, and then administered either GBE or vehicle in mice with established AAAs, which were continuously infused with AngII for another 56 days. GBE, but not the two major active components separately or synergistically, prevented aortic rupture, but not aortic dilation. The protection of GBE from aortic rupture was independent of systolic blood pressure, lipid, and inflammation. GBE also did not attenuate either aortic rupture or progressive aortic dilation in mice with established AAAs. GBE did not reduce the atherosclerotic lesion areas, either. In conclusion, GBE prevents aortic rupture in AngII-infused hypercholesterolemic mice, but only in the early phase of the disease development. 展开更多
关键词 ABDOMINAL aortic ANEURYSM angiotensin HYPERCHOLESTEROLEMIA GINKGO biloba extracts FLAVONOIDS GINKGOLIDES
叶用银杏林营造技术要点 预览
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作者 杨纪成 《现代农业研究》 2018年第6期75-76,共2页
从叶用银杏在人们康养生活中的重要意义到目前市场对银杏叶的巨大需求和精准扶贫中的脱贫攻坚作用,阐述了叶用银杏栽植的广阔前景。详细提出了在银杏园建设中所涉及的园址选择、整地作床、播种植苗、苗木管理等各生产环节的技术标准和要... 从叶用银杏在人们康养生活中的重要意义到目前市场对银杏叶的巨大需求和精准扶贫中的脱贫攻坚作用,阐述了叶用银杏栽植的广阔前景。详细提出了在银杏园建设中所涉及的园址选择、整地作床、播种植苗、苗木管理等各生产环节的技术标准和要求,对指导叶用银杏林的营造起到了规范作用。 展开更多
关键词 叶用银杏 营造 技术
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Human pharmacokinetics of ginkgo terpene lactones and impact of carboxylation in blood on their platelet-activating factor antagonistic activity
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作者 Xin-wei Liu Jun-ling Yang +13 位作者 Wei Niu Wei-wei Jia Olajide E.Olaleye Qi Wen Xiao-na Duan Yu-hong Huang Feng-qing Wang Fei-fei Du Chen-chun Zhong Yan-fen Li Fang Xu Qi Gao Li Li Chuan Li 《中国药理学报:英文版》 SCIE CAS CSCD 2018年第12期1935-1946,共12页
Terpene lactones are a class of bioactive constituents of standardized preparations of Ginkgo biloba leaf extract, extensively used as add-on therapies in patients with ischemic cardiovascular and cerebrovascular dise... Terpene lactones are a class of bioactive constituents of standardized preparations of Ginkgo biloba leaf extract, extensively used as add-on therapies in patients with ischemic cardiovascular and cerebrovascular diseases. This investigation evaluated human pharmacokinetics of ginkgo terpene lactones and impact of their carboxylation in blood. Human subjects received oral YinXing- TongZhi tablet or intravenous ShuXueNing, two standardized ginkgo preparations. Their plasma protein-binding and plateletactivating factor antagonistic activity were assessed in vitro. Their carboxylation was assessed in phosphate-buffered saline (pH 7.4) and in human plasma. After dosing YinXing-TongZhi tablet, ginkgolides A and B and bilobalide exhibited significantly higher systemic exposure levels than ginkgolides C and J; after dosing ShuXueNing, ginkgolides A, B, C, and J exhibited high exposure levels. The compounds’ unbound fractions in plasma were 45–92%. Apparent oral bioavailability of ginkgolides A and B was mostly >100%, while that of ginkgolides C and J was 6–15%. Bilobalide’s bioavailability was probably high but lower than that of ginkgolides A/B. Terminal half-lives of ginkgolides A, B, and C (4–7 h) after dosing ShuXueNing were shorter than their respective values (6–13 h) after dosing YinXing-TongZhi tablet. Half-life of bilobalide after dosing the tablet was around 5 h. Terpene lactones were roughly evenly distributed in various body fluids and tissues; glomerular-filtration-based renal excretion was the predominant elimination route for the ginkgolides and a major route for bilobalide. Terpene lactones circulated as trilactones and monocarboxylates. Carboxylation reduced platelet-activating factor antagonistic activity of ginkgolides A, B, and C. Ginkgolide J, bilobalide, and ginkgo flavonoids exhibited no such bioactivity. Collectively, differences in terpene lactones’ exposure between the two preparations and influence of their carboxylation in blood should be considered in investigating the relative 展开更多
关键词 GINKGO biloba human pharmacokinetics renal EXCRETION TERPENE LACTONE monocarboxylate platelet-activating factor
Content Determination of Quercetin in Ferment of Ginkgo biloba L.Leaves by HPLC
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作者 Dengfeng ZOU Hua ZHU +1 位作者 Junying RUAN Xiaohua WANG 《药用植物研究(英文版)》 2018年第6期23-25,32共4页
[Objectives]This study aimed to determine the content of quercetin in ferment of Ginkgo biloba L.leaves.[Methods]Bacillus licheniformis was selected for solid-state fermentation of G.biloba leaf powder,and the content... [Objectives]This study aimed to determine the content of quercetin in ferment of Ginkgo biloba L.leaves.[Methods]Bacillus licheniformis was selected for solid-state fermentation of G.biloba leaf powder,and the content of quercetin in ferment of G.biloba leaves was determined by reversed-phase high-performance liquid chromatography.First,the flavonoid glycosides were extracted with methanol.Then,the flavonoid glycosides were hydrolyzed with hydrochloric acid to prepare the test solution.The chromatographic conditions were as follows:Platisil ODS C 18 column(150 mm×4.6 mm,5μm);V methonal∶V water(0.4%phosphoric acid solution)=55∶45;flow rate of 1 mL/min;Shimadzu UV detector;detection wavelength of 360 nm.[Results]Quercetin was used as a reference substance.In the range of 0.002 6-0.036 0 g/L,there was a good linear relationship,with correlation coefficient of 0.999 8 and RSD of 1.26%.[Conclusions]This method is simple,easy to operate,accurate,and reproducible.It is suitable for the determination of quercetin content in G.biloba leaves. 展开更多
关键词 GINKGO biloba L.leaves MICROBIAL FERMENTATION High-performance liquid chromatography Content determination
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Effect of Ginkgo biloba leaf extract on cerebral cortex amino acid levels in cerebral ischemia model rats
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作者 Cui Yiran Wu Hongwei +3 位作者 Liu Mengting Qin Haijiao Liu Xin Yang Hongjun 《中医杂志:英文版》 SCIE CAS CSCD 2018年第5期676-684,共9页
OBJECTIVE: To investigate the effect of Ginkgo biloba leaf extract on amino acid levels in the cerebral cortex of cerebral ischemia model rats induced by middle cerebral artery occlusion(MCAO).METHODS: A rat model of ... OBJECTIVE: To investigate the effect of Ginkgo biloba leaf extract on amino acid levels in the cerebral cortex of cerebral ischemia model rats induced by middle cerebral artery occlusion(MCAO).METHODS: A rat model of cerebral ischemia was established by MCAO. Male rats were divided into a negative control group(Control), a sham-operated group(Sham), an ischemic group(MCAO), and an ischemic group treated with Ginkgo biloba leaf extract(MCAO_D). All groups were divided into two subgroups with occlusion times of 12 and 24 h, respectively. The levels of 18 endogenous amino acids in the cerebral cortex were quantified by triple quadrupole-liquid chromatography-mass spectrometry.RESULTS: Compared with the MCAO group, behavioral performance, neurological deficit score, and cerebral infarct volume were significantly improved in the MCAO_D group(P < 0.05, P < 0.01). Compared with the sham group, the levels of 17 amino acids in the cerebral cortex were markedly changed in the MCAO group. The levels of Alanine(Ala), Isoleucine(Ile), Glutamic acid(Glu), Serine(Ser), Valine(Val), Phenylalanine(Phe), Proline(Pro),Threonine(Thr), Lysine(Lys), Tyrosine(Tyr), Hydroxyproline(Hyp), Arginine(Arg), Leucine(Leu),Tryptophan(Trp), and Glycine(Gly) were increased(P < 0.001, P < 0.05), while levels of Gln and Tau were decreased(P < 0.001, P < 0.05). Compared with the MCAO group, Ginkgo biloba extract treatment in the MCAO_D group significantly down-regulated the levels of 11 amino acids, especially those of Arg, Thr, and Ser in 12 or 24 h.CONCLUSION: Injection of Ginkgo biloba leaf extract has a therapeutic effect on model rats with MCAO-induced cerebral ischemia by acting on amino acids in the cerebral cortex. This effect might be associated with the regulation of amino acid metabolism in the cerebral cortex. 展开更多
关键词 Cerebral ISCHEMIA GINKGO biloba leaf extract AMINO ACIDS Metabolism
秦岭凹叶厚朴内生真菌研究初报 预览
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作者 耿直 《中国现代中药》 CAS 2017年第1期92-95,共4页
目的:通过对凹叶厚朴内生真菌的鉴定研究,进一步丰富凹叶厚朴内生真菌种群的多样性,为更加合理有效的利用药用植物资源提供依据。方法:本文通过微生物方法从秦岭凹叶厚朴中分离纯化内生真菌,采用显微形态观察法对分离得到的内生真... 目的:通过对凹叶厚朴内生真菌的鉴定研究,进一步丰富凹叶厚朴内生真菌种群的多样性,为更加合理有效的利用药用植物资源提供依据。方法:本文通过微生物方法从秦岭凹叶厚朴中分离纯化内生真菌,采用显微形态观察法对分离得到的内生真菌进行初步鉴定。结果:对秦岭凹叶厚朴内生真菌进行分离纯化及初步鉴定,共分离得到内生真菌34株,其中四川都江堰共分离14株,优势菌群为枝孢属;陕西汉中共分离20株,优势菌群为镰刀菌属。初步鉴定结果为:1纲,3目,4科,9属。其中曲霉属3株,青霉属1株,葡萄孢属2株,胶帚霉属1株,镰刀菌属16株,枝孢属5株,交链孢属1株,束丝核菌属2株,组丝核菌属3株。结论:凹叶厚朴内生真菌的种群存在着极其丰富的多样性特征,为合理利用凹叶厚朴药用成分及保护凹叶厚朴药用植物资源提供理论依据。 展开更多
关键词 凹叶厚朴 内生真菌 多样性
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不同施肥处理对银杏幼苗生长的影响 被引量:1
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作者 甘青 吴雪松 +1 位作者 周琴 刘钊 《林业科技通讯》 2016年第12期19-20,共2页
以2年生银杏(Ginkgo biloba L.)幼苗为试验材料,研究了不同剂量的氮磷钾配比对银杏幼苗苗高、地径、冠幅的影响。结果表明,不同剂量的施肥处理对银杏幼苗的生长均有显著的促进作用。处理8效果最好,银杏幼苗的苗高、地径和冠幅均达到... 以2年生银杏(Ginkgo biloba L.)幼苗为试验材料,研究了不同剂量的氮磷钾配比对银杏幼苗苗高、地径、冠幅的影响。结果表明,不同剂量的施肥处理对银杏幼苗的生长均有显著的促进作用。处理8效果最好,银杏幼苗的苗高、地径和冠幅均达到了最大值,分别为54.1cm、18.5mm、10.67cm,与对照相比,分别提高31.3%、46.8%、48.19%。 展开更多
关键词 银杏 GINKGO biloba 施肥 幼苗 生长 影响
银杏叶提取物对缺血再灌注损伤保护作用及机制研究进展
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作者 李亚琳 权美平 《黑龙江畜牧兽医》 CAS 北大核心 2016年第12期64-67,共4页
缺血再灌注损伤指过量的自由基攻击重新获得血液供应的组织内的细胞造成的损伤,其对动物抗氧化系统的损伤最为明显,研究表明,应用抗氧化剂减轻损伤至关重要。银杏叶提取物(extract of ginkgo biloba,EGB)是从银杏叶中分离、纯化... 缺血再灌注损伤指过量的自由基攻击重新获得血液供应的组织内的细胞造成的损伤,其对动物抗氧化系统的损伤最为明显,研究表明,应用抗氧化剂减轻损伤至关重要。银杏叶提取物(extract of ginkgo biloba,EGB)是从银杏叶中分离、纯化的,主要含黄酮类、萜内酯和聚戊烯醇等,它是一种高效的氧自由基清除剂,已被广泛用于治疗多种疾病。针对银杏叶提取物对缺血再灌注损伤具有保护作用,归纳已经报道的各种动物模型中银杏叶提取物对缺血再灌注损伤的保护机制,文章重点概括了四种主要保护机制,以期为今后银杏叶提取物在医药界的应用和研究提供综合性参考。 展开更多
关键词 银杏叶提取物(extract of GINKGO biloba EGB) 缺血再灌注损伤 抗氧化 药理机制 研究进展
秃杉、厚朴树冠圆满度与主要测树因子的关系
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作者 廖先金 《福建林业科技》 2016年第3期203-207,共5页
对福建省连城邱家山国有林场经营区的秃杉、厚朴的树冠圆满度与胸径、树高、材积、形数等指标的关系进行调查研究。结果表明:2个树种的树冠圆满度均与胸径、树高、材积呈负相关,与形数呈正相关。其中秃杉的树冠圆满度与树高、材积相关... 对福建省连城邱家山国有林场经营区的秃杉、厚朴的树冠圆满度与胸径、树高、材积、形数等指标的关系进行调查研究。结果表明:2个树种的树冠圆满度均与胸径、树高、材积呈负相关,与形数呈正相关。其中秃杉的树冠圆满度与树高、材积相关关系显著,而与胸径、形数无显著相关关系;厚朴的树冠圆满度与胸径、树高、材积、形数均无显著相关关系。秃杉树冠圆满度的大小对秃杉生长影响较大,而对干形影响较小;厚朴树冠圆满度对其生长和干形影响均较小。 展开更多
关键词 秃杉 厚朴 树冠圆满度 胸径 树高 材积
Ginkgo biloba extract inhibits Akt/mTOR signaling mediated renal fibrosis in diabetic nephropathy 预览
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《中国药理学通报》 CAS CSCD 北大核心 2015年第B11期100-101,共2页
Aim To investigate the effects of Ginkgo biloba extract (GbE) on renal fibrosis in STZ induced diabetic rats and high glucose (HG) cultured proximal tubular epithelial cells (NRK-52E). Methods In vivo, rats were... Aim To investigate the effects of Ginkgo biloba extract (GbE) on renal fibrosis in STZ induced diabetic rats and high glucose (HG) cultured proximal tubular epithelial cells (NRK-52E). Methods In vivo, rats were randomized into six groups termed normal control, diabetes mellitus , low dose of GbE (50 mg · kg^-1 · d^-1) , in- termediate dose of GbE (100 mg · kg^-1·d^-1), high dose of GbE (200 mg · kg^-1 · d^-1) and rapamycin (1 mg·kg^-1·d^-l). After 12 weeks, the rats were sacrificed and then fasting blood glucose, creatinine (Cr) , blood u- rea nitrogen (BUN) , urine protein, kidney index, glycogen and collagen accumulation, and collagen IV and lami- NRK-52E cells were divided into six groups: normal nin expression were measured by different methods. In vitro, glucose (5.56 mmol · L^-1), high glucose (60 mmol · L^-1), low dose of GbE (10 mg · L^-1), intermediate dose of GbE (20 mg· L^-1), high dose of GbE (40 mg· L^-1) and rapamycin (20 nmol · L^-l). The morphological changes of cells were observed by microscopy after culturing for 48 h. Akt, roTOR and p70S6K, were examined by western blotting both in the renal cortex of rats and NRK-52E cells. Results Compared with diabetic rats, the lev- els of Cr, BUN, urine protein, kidney index, accumulation of glycogen and collagen, and expression of collagen IV and laminin in the renal cortex were all decreased in GbE treated rats. Furthermore, GbE ameliorated the morpho- logical changes of NRK-52E cells caused by HG. In addition, GbE reduced the expression of E-cadherin, oL-SMA, snail and phosphorylation of Akt, roTOR and p70S6K in diabetic renal cortexes and NRK-52E cells exposed to HG. Conclusion GbE was a satisfactory agent to prevent renal fibrosis in diabetic nephropathy, and this effect might be associated with the inhibition of the Akt/mTOR signaling pathway. 展开更多
关键词 DIABETIC NEPHROPATHY RENAL FIBROSIS Akt mTOR GINKGO biloba extract
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银杏叶中有效成分的提取及功能探究 被引量:1
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作者 杨小青 王新 +3 位作者 李瑞瑞 岳宇飞 龚彩华 唐志华 《饮料工业》 2014年第5期52-55,共4页
以汉中银杏树叶为原料,采用有机溶剂提取法对银杏叶中黄酮类化合物的提取工艺进行研究,通过单因素实验研究了不同提取温度、提取液浓度、提取次数、超声波对银杏叶中黄酮提取率的影响,对其显著影响因素采用正交试验,结果表明在提取... 以汉中银杏树叶为原料,采用有机溶剂提取法对银杏叶中黄酮类化合物的提取工艺进行研究,通过单因素实验研究了不同提取温度、提取液浓度、提取次数、超声波对银杏叶中黄酮提取率的影响,对其显著影响因素采用正交试验,结果表明在提取温度70℃、提取液浓度为70%、提取次数为3次为最佳提取条件,并且对黄酮类物质进行功能研究,结果表明黄酮类物质对绿豆幼苗有壮苗作用。 展开更多
关键词 银杏叶 黄酮 正交试验 乙醇 超声波 功能
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银杏小孢子囊壁发育的超微结构观察 预览 被引量:1
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作者 陆彦 郝敬超 +3 位作者 陈义芳 周卫东 程芳梅 王莉 《电子显微学报》 CAS CSCD 2014年第1期62-68,共7页
本文利用透射电镜、半薄切片等技术,对银杏小孢子囊壁的发育进行了观察和研究。银杏小孢子囊壁分为表皮、内壁、中层和绒毡层。(1)对小孢子囊壁的表皮、内壁和中层细胞的观察表明,小孢子母细胞时期,这些细胞均处于活跃的代谢和合... 本文利用透射电镜、半薄切片等技术,对银杏小孢子囊壁的发育进行了观察和研究。银杏小孢子囊壁分为表皮、内壁、中层和绒毡层。(1)对小孢子囊壁的表皮、内壁和中层细胞的观察表明,小孢子母细胞时期,这些细胞均处于活跃的代谢和合成阶段,含有大量的细胞器如线粒体、高尔基体、内质网和核糖体等;减数分裂时期细胞的细胞质浓度逐渐降低,细胞内分布有大液泡,其中表皮细胞的液泡膜上形成大量贮藏蛋白,内壁细胞的细胞壁逐渐皱缩,中层细胞纵向拉伸;有丝分裂时期,细胞的细胞质逐渐降解,内壁细胞切向壁和径向壁均出现大量乳突状纤维加厚,中层细胞解体,最后仅剩残余。(2)绒毡层细胞属于分泌型,在小孢子母细胞时期细胞内的细胞器丰富,其中质体在减数分裂过程中达到高峰;游离小孢子时期,粗糙内质网达到最大,绒毡层开始形成乌氏体,最终结合到花粉外壁,参与花粉外壁的形成;有丝分裂后期,绒毡层通过自溶的形式解体。以上结果显示,银杏的小孢子囊壁在为花粉发育提供营养和保护作用方面起着重要作用。 展开更多
关键词 银杏 小孢子囊壁 绒毡层 超微结构 GINKGO biloba L
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棕带突细蛾两种新寄主及其生物学研究 预览 被引量:1
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作者 徐家生 白海艳 戴小华 《中国森林病虫》 北大核心 2014年第1期5-7,46共4页
首次报道棕带突细蛾Gibbovalva kobusi Kumata & Kuroko的2种新潜叶寄主凹叶厚朴Mag-nolia officinalis subsp, biloba和深山含笑Michelia maudiae,描述了棕带突细蛾的危害状、潜道特征、形态结构及生活史,并给出了潜道、成虫和雌雄... 首次报道棕带突细蛾Gibbovalva kobusi Kumata & Kuroko的2种新潜叶寄主凹叶厚朴Mag-nolia officinalis subsp, biloba和深山含笑Michelia maudiae,描述了棕带突细蛾的危害状、潜道特征、形态结构及生活史,并给出了潜道、成虫和雌雄生殖器照片。 展开更多
关键词 棕带突细蛾 细蛾科 潜叶虫 凹叶厚朴 深山含笑 新寄主 生物学
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施肥、修剪等措施对凹叶厚朴中厚朴酚、和厚朴酚含量累积的影响 预览
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作者 胡乔铭 向德标 +2 位作者 裴刚 王晓明 蒋丽娟 《中国现代中药》 CAS 2013年第8期673-676,共4页
目的:提高凹叶厚朴的品质,缩短生产周期,为凹叶厚朴种植提供科学参考依据。方法:本次实验通过采用施肥、修枝、环割、铁丝环扎对凹叶厚朴进行处理,采用HPLC测定两年后厚朴中厚朴酚、和厚朴酚的含量,计算总酚含量增长率。结果:凹... 目的:提高凹叶厚朴的品质,缩短生产周期,为凹叶厚朴种植提供科学参考依据。方法:本次实验通过采用施肥、修枝、环割、铁丝环扎对凹叶厚朴进行处理,采用HPLC测定两年后厚朴中厚朴酚、和厚朴酚的含量,计算总酚含量增长率。结果:凹叶厚朴中总酚含量累积增长(1,)与肥料中的氮肥、磷肥正相关,与钾肥负相关,回归方程为:Y=1.804+2.470N+2.746P-15.616K(r=0.982)。修枝处理的凹叶厚朴中总酚的含量较前期增长了310%,环割处理的凹叶厚朴中总酚的含量较前期增加了125.65%,铁丝环扎处理的凹叶厚朴中总酚的含量较前期增加了343.2%,而同期的空白组中凹叶厚朴中总酚的含量较前期增加了84.62%。实验结果显示不同栽培措施的效果由大到小的顺序是:铁丝环扎〉修枝〉环割。结论:凹叶厚朴中厚朴酚、和厚朴酚含量的积累可以通过改变土壤的肥力、环割、修枝等栽培措施得以提高。 展开更多
关键词 凹叶厚朴 施肥 修枝 环割 环扎 厚朴酚 和厚朴酚
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木兰科四种植物种子油的提取及脂肪酸成分分析 预览 被引量:8
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作者 刘举 陈继富 《广西植物》 CAS CSCD 北大核心 2013年第2期208-213,共6页
采用超声波辅助提取法和微波辅助提取法同时提取白玉兰、凹叶厚朴、深山含笑和醉香含笑四种木兰科植物的种子油,种子油甲酯化后,运用气相色谱—质谱联用技术测定其脂肪酸成分。结果表明:四种植物种子油的提取率不同,白玉兰平均为27.35... 采用超声波辅助提取法和微波辅助提取法同时提取白玉兰、凹叶厚朴、深山含笑和醉香含笑四种木兰科植物的种子油,种子油甲酯化后,运用气相色谱—质谱联用技术测定其脂肪酸成分。结果表明:四种植物种子油的提取率不同,白玉兰平均为27.35%、凹叶厚朴23.34%、深山含笑31.66%,醉香含笑9.27%。不同提取方法所得到的种子油脂肪酸成分和相对含量不同,但四种种子油的主要脂肪酸成分相同,包括油酸、亚油酸、硬脂酸和棕榈酸。 展开更多
关键词 白玉兰 凹叶厚朴 深山含笑 醉香含笑 种子油 脂肪酸
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濒危植物凹叶厚朴幼苗更新及环境解释 预览 被引量:9
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作者 杨旭 杨志玲 +2 位作者 雷虓 陈慧 麦静 《林业科学》 CAS CSCD 北大核心 2013年第12期36-42,共7页
凹叶厚朴为我国二级保护野生植物,由于其较高的药用价值,野生资源遭到无节制的盗砍,造成种群数的衰退和群落残败.调查浙江省遂昌县桂洋林场不同群落野生凹叶厚朴的更新状况,结果表明:凹叶厚朴种群大小级为不典型的“J”型,种群在较长... 凹叶厚朴为我国二级保护野生植物,由于其较高的药用价值,野生资源遭到无节制的盗砍,造成种群数的衰退和群落残败.调查浙江省遂昌县桂洋林场不同群落野生凹叶厚朴的更新状况,结果表明:凹叶厚朴种群大小级为不典型的“J”型,种群在较长的时间内保持稳定状态;凹叶厚朴以萌生更新为主,随着群落郁闭度的增加,萌生苗的比例增高,但不同群落平均萌枝数量、平均胸径及株高无显著差异.实生苗随着郁闭度的增加植株呈现变矮、变细的趋势;凹叶厚朴实生和萌生苗在不同群落中年龄结构差异均极大,针阔叶混交林中更新良好,针叶林大量高龄幼苗生长缓慢,且植株不易进入上层空间,常绿阔叶林中存在严重的更新不良现象;各群落中,更新幼苗株高和胸径增长量均随郁闭度的增加呈现极显著下降的趋势,其中实生苗的下降趋势更为明显;影响实生更新的主要环境因子为草本层盖度和厚度、枯落物盖度、腐殖质厚度及土壤含水率;影响种群萌生更新的主要环境因子为群落的光照及温湿度.因此,降低上层林冠密度,减少草本层、枯落物等的覆盖对于维持种群的发展、缓解其濒危状况具有重要的意义. 展开更多
关键词 凹叶厚朴 年龄结构 更新特征 幼苗生长动态 更新障碍
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凹叶厚朴树体厚朴酚、和厚朴酚含量变化模型的研究 被引量:4
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作者 王晓明 杨硕知 +5 位作者 裴刚 蒋丽娟 宋庆安 蔡能 李永欣 曾慧杰 《中南林业科技大学学报》 CAS CSCD 北大核心 2012年第2期 1-5,共5页
为了研究凹叶厚朴树厚朴酚、和厚朴酚的积累分布规律,以10年生凹叶厚朴为试验材料,建立了凹叶厚朴树体解析木高度与厚朴酚、和厚朴酚及树皮厚度含量的数学模型。结果表明:解析木高度与总酚含量、厚朴酚含量、和厚朴酚含量关系最优模型... 为了研究凹叶厚朴树厚朴酚、和厚朴酚的积累分布规律,以10年生凹叶厚朴为试验材料,建立了凹叶厚朴树体解析木高度与厚朴酚、和厚朴酚及树皮厚度含量的数学模型。结果表明:解析木高度与总酚含量、厚朴酚含量、和厚朴酚含量关系最优模型依次为y=─0.053636x3+0.665503x2─2.543869x+3.964848,y=─0.008939x3+0.110233x2─0.419464x+0.693864,y=─0.044697x3+0.555271x2─2.124405x+3.270985;树体解析木高度与树皮厚度关系最优模型为y=─0.008965x3+0.031331x2─0.143492x+4.941212,可用于凹叶厚朴树体厚朴酚、和厚朴酚含量的预测,为科学采收厚朴皮提供了理论依据。 展开更多
关键词 凹叶厚朴 数学模型 厚朴酚 和厚朴酚 树皮厚度
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