首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
1.
为研究蝎毒素BmkTXKβ对家兔心房肌细胞瞬间外向钾电流(Ito)的影响,采用全细胞膜片钳技术记录应用BmkTXKβ前后的Ito电流. 结果显示BmkTXKβ(1 μmol/L)使心房肌细胞Ito(刺激电压为+50 mV)从(13.63±0.87)pA/pF减少到(7.98±0.78)pA/pF,抑制率为41.4% (n=16, P<0.001).冲洗后, Ito部分恢复至(11.18±0.82)pA/pF (n=6, P<0.01,与给药后比较).在0.01~100 μmol/L范围内BmkTXKβ呈浓度依赖性地抑制Ito,IC50的均值为0.95 μmol/L (n=10, P<0.01),但无频率依赖性(n=6,P>0.05). 1 μmol/L的BmkTXKβ可使Ito通道的失活动力学曲线明显左移,V1/2分别为(-23.6±2.7) mV和(-35.3±3.6) mV(n=8,P<0.05),曲线斜率基本不变.同时可使Ito通道的恢复过程明显减慢,恢复曲线右移,τ值从(51.2±8.5) ms延长至(93.5±13.4) ms(n=9,P<0.01),但不影响其激活过程.据此推断BmkTXKβ对家兔心房肌细胞Ito具有显著的抑制作用,主要作用于失活过程,延长该通道的恢复时间.  相似文献   

2.
张尹  于志国  金彪 《生态学报》2020,40(24):8936-8947
为研究北方泥炭沼泽湿地二氧化碳(CO2)和甲烷(CH4)浓度随深度的变化规律及其影响因素,选取欧洲北部典型雨养泥炭地贝尔山湿地(BBM)和舒特兹山湿地(SBM)两个采样点,通过原位采集泥炭剖面温室气体、孔隙水以及土壤样品,结合傅里叶变换红外光谱(FTIR)技术、碳氮同位素技术,探讨泥炭土壤的分解程度及温室气体浓度变化的关系。研究结果表明:(1)BBM采样点地下部的CO2浓度变化规律总体呈现随深度波动减少趋势,值多在3000 μmol/L附近波动,最大值为4210.74 μmol/L(120 cm),SBM采样点的CO2浓度随深度先增后减,60 cm以上在1800 μmol/L附近波动,60 cm以下在3000 μmol/L附近波动,最大值为4191.94 μmol/L(90 cm);BBM和SBM地下部CH4浓度都随深度增大,并且在60cm以下浓度增加较快,BBM最大值为735.90 μmol/L(260 cm),SBM最大值为543.51 μmol/L(170 cm)。(2)BBM和SBM的δ13CCH4的值均较小,表明大部分的12CH4仍被储存在泥炭土壤中,而两个采样点的δ13CCO2和分馏系数αc均随深度增加,表明泥炭土中产甲烷方式为浅层以乙酸产甲烷为主,深层以H2还原CO2为主。(3)C/N、碳氮同位素比值、FTIR均显示SBM和BBM的有机质分解程度较低,因为两个采样点的低可溶性有机碳浓度和低pH值不利于分解,表明该地储存着大量有机碳。通过探讨北温带典型泥炭地温室气体的浓度变化规律及其影响因素,结果可为全球泥炭湿地碳排放提供理论支撑。  相似文献   

3.
成年大鼠海马CA1区锥体神经元外向整流氯离子单通道特性   总被引:3,自引:0,他引:3  
采用膜片钳内面向外式技术,在急性分离成年大鼠海马CAl区锥体细胞上记录到了外向整流氯离子通道(outwardly rectifying chloride channel,ORCC).长时间去极化(≥60 mV)刺激后,在30%的游离膜片上记录到有外向整流特性的单通道氯电流,膜电位在-60 mV到0 mV之间的单通道电导为(16.58±1.54) pS(n=10),而在0 mV到+60 mV之间电导为(40.92±3.17) pS.通道开放概率有明显的电压依赖性(膜电位-60 mV时,Po=0.44±0.12;膜电位为+60 mV时,Po=0.86±0.06, n=10).在对称Cl浓度(150 mmol/L)时,通道翻转电位为(-4.17±1.84) mV.当溶液中部分NaCl被葡萄糖酸钠替代后,翻转电位为:(-34.23±4.86) mV ([Cli/[Clo=(30 mmol/L)/(150 mmol/L)),接近氯离子通道的理论值,这表明通道具有氯离子选择性.浴槽液中分别加入氯通道阻断剂DIDS和SITS可以使+40 mV的通道开放概率从(0.83±0.06)和(0.86±0.06)分别降低到(0.12±0.05)和(0.13±0.04)(n=5),冲洗后可使开放概率基本恢复.上述研究结果显示,在成年大鼠海马CA1神经元上存在外向整流氯离子通道.  相似文献   

4.
中华绒螯蟹眼柄MTXO细胞GABA受体通道研究   总被引:3,自引:0,他引:3  
采用全细胞膜片钳技术测定了中华绒螯蟹(Eriocheir sinensis)眼柄视神经节端髓X器官(MTXO)三种类型神经内分泌细胞对0.01~5mmol/L γ氨基丁酸(γ-aminobutyric acid,GABA)的反应,并结合选择性拮抗剂和激动剂的使用进行了GABA受体研究.在电流钳模式下,依据不同Nernst Cl电位,三种类型细胞均对GABA产生去极化或超级化反应.在电压钳模式下,GABA激活Cl通道电流(IGABA).IGABA在灌流GABA后约1 200 ms内激活,800 ms内达到峰值,没有明显的脱敏反应,反转电位接近Nernst Cl电位.IGABA幅值呈浓度依赖性,激活阈值为0.01 mmol/L,约在0.5 mmol/L达到饱和.药理学实验结果表明,中华绒螯蟹眼柄神经内分泌细胞GABA受体是Cl通道蛋白,对Cl离子通道阻断剂Picrotoxin和Niflumic acid敏感,但是对GABAA受体拮抗剂Bicuculline和GABAC受体激动剂cis-4-aminocrotonic acid (CACA)和trans-4-aminocrotonic (TACA)均不敏感.  相似文献   

5.
为探究环境因子对针叶蕨藻(Caulerpa sertularioides)生长的影响,对不同盐度、温度和光照强度下针叶蕨藻的生长和叶绿素荧光参数进行了研究。结果表明:藻体日特定生长率(SGR)、最大光量子产量(Fv/Fm)、实际光合效率(Yield)、电子传递速率(ETR)和光化学淬灭(qP)随盐度升高呈先上升后下降的变化趋势,非光化学淬灭(qN)则呈相反的变化趋势,藻体光合活性和固碳效率在盐度27.5‰时达到最高,且与25‰和30‰盐度的差异显著(P<0.05,n=3)。藻体SGR、Fv/Fm、Yield、ETR和qP随温度升高而下降,qN则相反,藻体光合活性和固碳效率在26℃下达到最高,且与28℃和30℃的差异显著(P<0.05,n=3)。藻体的SGR、Fv/Fm、Yield、ETR和qP随光照强度升高呈先上升后下降的变化趋势,qN则相反,且在18.75 μmol/(m2·s)弱光照下出现轻微光抑制,藻体生长、光合活性及固碳效率在光照强度25.00 μmol/(m2·s)时达到最高,但与18.75和31.25 μmol/(m2·s)的差异不显著(P>0.05,n=3)。因此,针叶蕨藻在27.5‰盐度、26℃和25.00 μmol/(m2·s)光照强度下生长最快且光合作用能力最高。  相似文献   

6.
Previous work has shown that the feet of terrestrial and freshwater snails are important in calcium regulation, often secreting granules of CaCO3. This phenomenon has not, until now, been observed in marine snails. Here we report the presence of CaCO3 granules in the trail mucus of Littorina littorea (L.), L. saxatilis (Olivi) and L. obtusata (L.) Fixed mucus trails on plastic coverslips were examined by X-ray microanalysis under the SEM. Of the single-metal granules observed in the mucus trails the most abundant were of calcium (means: L. littorea, 440 mm−2; L. saxatilis, 401 mm−2; L. obtusata, 348 mm−2) followed for each species by silicon (maximum mean density: L. saxatilis, 120 mm−2) and iron (maximum mean density: L. saxatilis, 65 mm−2) granules. Single-metal granules of Al, Ti, Mg and P were also found but only in the mucus trails of L. obtusata, perhaps reflecting its different collection site from the other two species. The mean size of the calcium granules showed significant interspecific variation (L. littorea, 1.32 μm diameter±0 08 μm, n = 143; L. saxatilis, 1.80 μm±0.12, n = 113; L. obtusata, 2.14 μm±0.09, n = 167). Most calcium granules (L. littorea, 80%, n = 35; L. saxatilis, 57%, n = 113; L. obtusata, 69%, n = 167) were attached to, or embedded within, microthreads of mucus which tended to run parallel to the direction of locomotion. The significance of this is unknown although it may imply that the CaCO3 granules are secreted with the mucus. It is concluded that calcium losses via this route are too small for pedal mucus to function significantly in ionoregulation of calcium. The calcium in the trail may therefore perform other functions, for example indicating trail polarity.  相似文献   

7.
左嫚  陈奇伯  黎建强  杨关吕  胡景  孙轲 《生态学报》2021,41(11):4552-4561
为研究枯落物输入变化对云南松(Pinus yunnanensis)林地CO2释放的影响。本研究于2018年3月至2020年2月,应用枯落物添加和去除实验(DIRT),设置对照(CK)、双倍枯落物(DL)、去除枯落物(NL)、去除有机层和A层(O/A-Less)、去除根系(NR)和无输入(NI)6个处理水平,采用Li-6400便携式光合作用测量仪及TRIME-PICO 64/32土壤温度水分测定仪对不同处理样地每月的CO2通量(Rs)、土壤温度和土壤水分(15cm)进行了测定。结果表明:(1)不同处理样地CO2通量均呈现出明显的月变化,7至8月最高,1至4月最低,平均值表现为Rs (DL)=8.10 μmol m-2 s-1 > Rs (CK)=6.27 μmol m-2 s-1 > Rs (NL)=5.44 μmol m-2 s-1 > Rs (NR)=4.46 μmol m-2 s-1 > Rs (O/A-Less)=3.86 μmol m-2 s-1 > Rs (NI)=2.94 μmol m-2 s-1。(2)与CK相比,DL样地CO2通量升高了29.12%,而去除地上枯落物和地下根系样地CO2通量显著降低,CO2通量平均变幅分别为α(NR)=-28.85%,α(NI)=-53.14%,α(O/A-Less)=-38.46%,α(NL)=-13.29%。(3)不同处理土壤水分和土壤温度均存在显著的月变化(P<0.01),NL和O/A-Less的土壤水分显著低于CK,而其余处理与CK间无显著差异(P>0.05);不同处理间土壤温度表现为NR和NI均显著高于CK,其余处理与CK间无显著差异(P>0.05)。(4)不同处理样地CO2通量与土壤温度呈显著指数相关(P<0.01),与土壤水分在NI和O/A-Less处理中无显著相关(P>0.05);与CK相比,NI、O/A-Less和NL处理的Q10增加,而NR和DL处理的Q10则降低;不同处理林地CO2通量与土壤水热因子双因素模型能更好的解释林地CO2通量的变化。本研究表明枯落物不同处理通过改变土壤碳输入和土壤环境因子从而影响生态系统碳排放,研究结果可为未来气候变化和人为干扰下云南松林的碳循环提供基础数据。  相似文献   

8.
利用CID型便携式光合作用仪测定不同NaCl浓度下杠柳叶片净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、水分利用效率(WUE)及光能利用率(LUE)生理参数的光响应过程,阐明盐分胁迫下其对光照响应的规律,探讨有利于杠柳正常生长的盐分浓度和光照条件。结果表明:(1)各盐分浓度下杠柳叶片光补偿点(LCP)在21.89~65.05 μmol·m-2·s-1之间变动,介于阴性植物与阳性植物之间;杠柳随土壤盐分的不同,其光合作用参数对光照强度表现出一定的适应性和可塑性;50 mmol·L-1盐分浓度下杠柳光合同化能力最强,最有利于其干物质的积累,表现出一定的耐盐性。(2)轻度的盐分胁迫(小于50 mmol·L-1)可以提高杠柳叶片的PnGsWUELUE,而盐分胁迫对杠柳的Tr有抑制作用,并随着盐分浓度的增加其抑制作用愈强烈。(3)维持杠柳正常生长的土壤盐分浓度小于50 mmol·L-1,最佳PAR为1 000~2 000 μmol·m-2·s-1;而保持杠柳最大WUELUE的光照强度分别为800和100 μmol·m-2·s-1。  相似文献   

9.
基于腺酶催化尿素分解产生氨,以氨气敏电极为基础电极,用含脲酶丰富的谷氨酸棒状杆菌研制成测定尿素的微生物传感器.在30℃、pH8.0、0.1mol/L磷酸盐缓冲液中,该传感器的线性范围为1.1×10-4~1.4×10-2mol/L,斜率为51.2mV/decade,检测下限为1.0×10-5mol/L,寿命可达45d.考察了传感器响应初速和底物浓度之间的关系,测定了微生物膜中脲酶的表观米氏常数Km及最大响应初速vm.  相似文献   

10.
用Blue Sepharose CL-6B快速纯化天花粉蛋白   总被引:8,自引:0,他引:8  
差光谱显示染料cibacron blue F3GA与天花粉蛋白(TCS)有特异性结合,复合物在可见光部分的最大吸收波长在690 nm,摩尔消光系数ε=2.6×10-3(mol/L)-1·cm-1,解离常数Kd=1.8 μmol/L,0.5 mol/L NaCl可使复合物解离.根据这一特点,用Blue-Sepharose CL-6B凝胶从栝篓块茎中亲和纯化了TCS.此法快速、简便、高效,易于大量制备.  相似文献   

11.
黄鳝ISSR-PCR反应体系的建立及条件优化   总被引:2,自引:1,他引:1  
以黄鳝基因组DNA为模板,采用正交试验设计方法,对各反应因子、引物退火温度和循环参数进行优化.建立了黄鳝的最适ISSR-PCR反应体系,25 μl反应体系中含2.5 mmol/ L Mg2+,250 μmol/ L dNTPs,0.25 μmol/ L 引物,1.0 U Taq DNA聚合酶,30 ng DNA模板.最佳反应程序:94℃预变性5 min;94℃变性40 s,48~57℃复性40 s(随引物而确定),72℃延伸1.5 min,循环次数40;72℃延伸10 min.利用所建立的ISSR反应体系,获得了清晰、重复性好、多态性高的DNA谱带.  相似文献   

12.
Cai Z  Zhang X  Lu DF  Gan JN 《Luminescence》2012,27(4):256-261
A novel chemiluminescence (CL) system was established for the determinations of daidzein in pharmaceutical preparations and to assess its ability to scavenge hydroxyl radicals. It was shown that a strong CL signal generated when eosin Y was mixed with Fenton reagent was decreased significantly when daidzein was added to the reaction system due to partial scavenging of the hydroxyl radicals in the solution. The extent of decrease in the CL intensity had a good stoichiometric relationship with the daidzein concentration. Based on this, we developed a new method for the determination of daidzein, using a flow‐injection chemiluminescence (FI–CL) technique. Under the optimal conditions, the linear range of daidzein concentration was 8.0 × 10–8–3.0 × 10–6 mol/L (R = 0.9982), with a detection limit of 9.0 × 10–9 mol/L (S:N = 3), and the RSD was 5.8% for 1.0 × 10–6 mol/L daidzein (n = 11). This method was successfully used in the determination of daidzein in tablets and for evaluation of the hydroxyl radical‐scavenging capacity of daidzein. The possible reaction mechanism of the CL system is discussed. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

13.
虎纹蛙促性腺激素释放激素分泌调节的离体研究   总被引:1,自引:0,他引:1  
李远友  林浩然 《动物学报》2002,48(2):221-226
利用离体静态孵育系统和放射免疫测定法,研究了性成熟的虎纹蛙雌蛙离体的视前-下丘脑-正中隆起(P-H-ME)片段促性腺激素释放激素(GnRH)的分泌调节。结果表明:γ-氨基丁酸(GABA)对成熟前期蛙离体P-H-ME片段的哺乳类GnRH(mGnRH)的释放有显著的刺激作用;随着GABA作用浓度的增加,刺激作用逐渐增强。100μmol/L的多巴胺(DA)及1μmol/L和10μmol/L的雌二醇(E2)则显著抑制鸡ⅡGnRH(cGnRH-Ⅱ)的释放。10μmol/L和100μmol/L的睾酮(T)以及10μmol/L的E2显著刺激冬眠期蛙P-H-ME片段mGnRH的释放。这些结果表明,GABA,DA及E2和T对虎蚊蛙GnRH的释放有直接的调节作用。  相似文献   

14.
We have developed a chemiluminescent flow injection method for analysis of bile acid, glucose and ATP using the chemiluminescent assay of NADH using 1-methoxy-5-methylphenazinium methyl sulphate (1-MPMS)/isoluminol(IL)/microperoxidase (m-POD) system and immobilized enzyme reactors such as 3α-hydroxysteroid dehydrogenase, glucosedehydrogenase, hexokinase and glucose-6-phosphate dehydrogenase. The standard curves were obtained in the range of 5 ~ 100 pmol for bile acid, 0.5 ~ 5.0 nmol for glucose and 10?7 ~ 10?5 mol/L for ATP. The coefficient of variation for each assay was not more than 4.1% for bile acid, 2.3% for glucose and 5.3% for ATP, respectively.  相似文献   

15.
We developed a highly sensitive chemiluminescent (CL) assay for hydrogen peroxide using 10‐methyl‐9‐(phenoxycarbonyl) acridinium fluorosulfonate (PMAC) that produced chemiluminescence under neutral conditions and applied it to an enzyme immunoassay (EIA). One picomole of hydrogen peroxide could be detected using the optimized PMAC‐CL method and 6.2 × 10‐20 mol β‐d ‐galactosidase (β‐gal) could be detected by combining an indoxyl derivative substrate and the proposed PMAC‐CL method. This highly sensitive CL β‐gal assay was applied to an EIA for thyroid‐stimulating hormone (TSH) using β‐gal as a label enzyme; 0.02–100.0 μU/mL TSH in human serum could be assayed directly and with high reproducibility. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

16.
分离培养猪脂肪间充质干细胞(adipose mesenchymal stem cells, AMSCs),流式细胞仪鉴定其表面标记.利用MTT比色检测不同浓度的全反式维甲酸(all trans retinoic acid, ATRA)对猪AMSCs增殖的影响;光学显微镜下观察猪AMSCs向脂肪细胞分化的形态学变化;油红O染色提取法分析不同浓度ATRA对猪AMSCs成脂分化的影响;RT PCR检测脂肪细胞分化标志基因LPL和aP2 mRNA的变化.MTT比色结果显示,生理浓度(1×10-9~1×10-8 mol/L)和药理浓度(1×10-7~1×10-5 mol/L)ATRA对猪AMSCs增殖均没有影响.油红O染色提取法结果表明,除1×10-7 mol/L ATRA对猪AMSCs成脂分化没有影响外,生理浓度(1×10-9~1×10-8 mol/L)和其它药理浓度(1×10-6~1×10-5 mol/L)ATRA均显著抑制猪AMSCs成脂分化(P<0.05).RT-PCR检测显示,ATRA显著抑制脂肪细胞分化标志基因LPL和aP2 mRNA表达(P<0.05).  相似文献   

17.
类风湿关节炎中白三烯B4诱导TNF-α和IL-1β的表达   总被引:1,自引:0,他引:1  
为了探讨类风湿关节炎的发病过程中白三烯B4(leukotriene,LTB4)对TNF-α和IL-1β表 达的影响.加入外源性LTB4或者在LIT存在的情况下,加入苯丁抑制素(bestatin,LTA4水解酶 抑制剂)和MK-886(5-脂氧合 酶激动蛋白抑制剂)后, 采用实时PCR和酶联免疫吸附分析法来检测原代培养的类风湿滑膜细胞及培养上清液中TNF-α和IL-1β在mRNA及蛋白水平的表达.外源性的LTB4 10-8mol/L使TNF-α和IL-1β mRNA水平表达分别增加了14倍和1倍, 蛋白水平分别增加了3倍.加入LIT刺激内源性的LTB4增加了14倍后,使TNF-α和IL-1βmRNA水平表达分别增加了145倍和12倍, 蛋白水平分别增加了3倍.在LIT存在的情况下, MK-886 10 μmol/L使LTB4合成降低了62%(P<0.000 1), 使TNF-α和IL-1β mRNA水平表达分别降低了66%(P<0.05)和71%(P<0.001),它们的蛋白水平分别降低了75%和70%(P<0.01). 100 μg/ml苯丁抑制素使LTB4合成降低了78%(P<0.000 1), 使TNF-α和IL-1β mRNA水平表达分别降低了86%(P<0.001)和79%(P<0.01), 它们的蛋白水平分别降低了84%和76%(P<0.05). 在类风湿关节炎中,LTB4诱导TNF-α和IL-1β的表达. 这一结果为类风湿关节炎发病机制进一步探讨提供了一条新思路.  相似文献   

18.
A simple chemiluminescent immunoassay (CLIA) for urinary albumin has been developed based on the use of a chemiluminescent acridinium ester-labelled human albumin and a commercially available antiserum. It includes two incubation steps and a second polyethylene glycol-assisted antibody separation. The sensitivity of detection is 0.016 mg/l, the assay working range is 0.1-5 mg/l, and the inter-assay CVs are ≤ 15%. Using 10? and 50-fold sample dilutions in assay buffer, a wide working range (1-250 mg/l) is obtained covering normal and pathological conditions. Timed overnight urine samples (bed rest conditions) were collected on three consecutive days for each patient. Albumin excretion rate (AER) was 4.7 ± 2.7 μg/min (x ± SD), range 1-15.9 μg/min in 36 healthy subjects (17♂, 19♀, ages 4-56 years), with day-to-day variations of 28.5 ± 20% (x ± SD), range 3.3-76.1%. The use of an acridinium ester as a chemiluminescent (CL) label overcomes the disadvantages of short shelf-life and health and safety hazards associated with radioisotopes. Results compare favourably with those obtained using a commercially available RIA kit.  相似文献   

19.
A simple and sensitive DNA‐stablized gold nanoparticle (AuNP)‐based chemiluminescent (CL) probe for detecting mercury ion (Hg2+) in aqueous solution has been developed. The CL strategy relies upon the catalytic activity of unmodified AuNPs on the luminol–H2O2 CL reaction, and the interaction of unmodified AuNPs with DNA. The unmodified AuNPs can effectively differentiate unstructured and folded DNA. The DNA desorbs from AuNPs in the presence of Hg2+, leading to the increase in CL signal. By rationally varying the number of thymine in single‐strand oligonucleotides, the detection range could be tuned. Employing single‐strand oligonucleotides with 14 thymine in the detecting system, a sensitive linear range for Hg2+ ions from 5.0 × 10–10 to 1.0 × 10–7 mol/L and a detection limit of 2.1 × 10–10 mol/L are obtained. Changing the number of thymine to 10 and 6, it leads to a narrow detection range but a high sensitivity. Besides, DNA‐based CL nanoprobes exhibit a remarkable selectivity for Hg2+ ions over a variety of competing metal ions. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

20.
Luminol chemiluminescence was used to evaluate the scavenging of superoxide, hydroxyl and alkoxy radicals by four antioxidants: dipyridamole, diethyldithiocarbamic acid, (+)catechin, and ascorbic acid. Different concentrations of these compounds were compared with well-known oxygen radical scavengers in their capacity to inhibit the chemiluminescence produced in the reaction between luminol and specific oxygen radicals. Hydroxyl radicals were generated using the Fenton reaction and these produced chemiluminescence which was inhibited by diethyldithiocarbamate. Alkoxy radicals were generated using the reaction of tert-butyl hydroperoxide and ferrous ion and produced chemiluminescence which was inhibited equally by all of the compounds tested. For the determination of superoxide scavengers we describe a new, simple, economic, and rapid chemiluminescence method consisting of the reaction between luminol and horseradish peroxidase (HRP). With this method it was found that 40 nmol/l dipyridamole, 0.18 μmol/l ascorbic acid, 0.23 μmol/l (+)catechin, and 3 μmol/l diethyldithiocarbamic acid are equivalent to 3.9 ng/ml superoxide dismutase (specific scavenger of superoxide) in causing the same degree of chemiluminescence inhibition. These results not only indicated that the antioxidative properties of these compounds showed different degrees of effectiveness against a particular radical but also that they may exert their action against more than one radical.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号