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1.
金丝桃苷对大鼠局灶性脑缺血/再灌注损伤的脑保护作用   总被引:1,自引:0,他引:1  
目的研究金丝桃苷(Hyp)在缺血性脑血管病中的神经保护作用。方法78只Wistar大鼠随机分为假手术组、缺血对照组、Hyp组,后2组又根据观察时间点不同分为脑缺血2h后再灌注1、3、6、12、24、48h 6个亚组,每组6只,线栓法建立大鼠缺血再灌注模型,固定取脑干,湿比重法测定脑组织含水量。结果自3h起同时间点对照组和Hyp组脑水含量均显著高于假手术组(P<0.05),其中Hyp组显著低于对照组(P<0.05)。结论Hyp能有效减轻大鼠缺血/再灌注早期脑水肿,有显著脑保护作用。  相似文献   

2.
目的研究槲皮素-3-半乳糖苷(金丝桃苷)对缺血性脑血管病的神经保护作用。方法78只Wistar大鼠随机分为假手术组、缺血对照组、金丝桃苷缺血组(Hyp组),后2组又根据观察时间点不同分为脑缺血2h后再灌注,3h、6h、12h、48h六个亚组,每组各6只,线栓法建立大鼠缺血再灌注模型。SABC免疫组化染色法分别记录各组不同时间点的P-选择素和E-选择素阳性反应血管数。结果自3h起同时间点金丝桃苷苷组P-选择素、E-选择素水平均显著低于对照组(P<0.05)。结论金丝桃苷能有效抑制大鼠缺血/再灌注早期P、E-选择素的表达,有显著脑保护作用。  相似文献   

3.
目的 探讨GLP-1受体激动剂Exendin-4腹腔给药对大脑中动脉闭塞(MCAO)再灌注所致大鼠脑缺血/再灌注损伤的神经保护作用。方法 SD大鼠术前1 h腹腔注射Exendin-4,MCAO再灌注24 h后进行神经功能缺损评分,TTC染色计算脑梗死体积,免疫荧光观察神经元和小胶质细胞生存数量及检测凋亡通路相关蛋白的相对表达水平。结果 Exendin-4能够保护由于MCAO再灌注后所致的脑缺血再灌注损伤,减少了脑梗死体积,降低皮层凋亡蛋白的相对表达水平,抑制神经元凋亡。结论 Exendin-4可以对MCAO再灌注所致脑缺血/再灌注损伤具有神经保护作用,该作用是通过抑制凋亡蛋白的产生,从而抑制细胞凋亡。  相似文献   

4.
目的研究尼莫地平和超氧化物歧化酶(superoxide dismutase,SOD)联合治疗大鼠脑缺血/再灌注损伤的神经保护作用。方法将45只成年雄性Wistar大鼠随机分成4组,尼莫地平组、超氧化物歧化酶组、联合药物(尼莫地平加超氧化物歧化酶)组和对照组。应用线栓法制作大鼠MCAO模型,缺血后4h行再灌注。于再灌注前20min、再灌注后12h和36h尾静脉给药;48h后计算大鼠存活率、行神经功能缺损评分、脑血流量和脑梗死体积测定。结果①大鼠存活率分别为:41.7%、27.3%、70.0%和25.0%。联合药物组较对照组的存活率明显增加(P<0.05)。②神经功能缺损评分为:4.39±0.197、4.47±0.492、3.79±0.521和4.67±0.709。联合药物组较对照组的神经功能缺损明显减少(P<0.01),较尼莫地平或SOD组也明显减少(P<0.05)。③脑组织血流量为:96±23%、81±19%、129±47%和79±41%。与对照组相比三个药物组的脑血流量均增加(P<0.05)。联合药物组的脑血流量增加又明显高于单药治疗组(P<0.05)。④梗死体积为:261.0±55.2、261.2±59.3、128.5±58.4和383.5±58.8mm3。联合药物组梗死体积明显小于对照组(P<0.05)和两个单药组(P<0.01,P<0.05)。结论尼莫地平和超氧化物歧化酶联合用药对脑缺血/再灌注损伤具有神经保护作用,并且优于单一药物治疗。  相似文献   

5.
目的研究人参皂苷Rg2对脑缺血再灌注损伤的保护作用。方法采用线栓法制成大鼠大脑中动脉栓塞再灌注模型,术后连续腹腔注射5 d给予不同剂量的人参皂苷Rg2,采用Longa 5级评分标准对脑缺血再灌注大鼠进行神经功能评定,采用TTC染色测定梗死面积,酶组织化学染色显示乙酰胆碱酯酶神经元,比色法测定乙酰胆碱酯酶活性。结果神经功能评分显示人参皂苷Rg2低、中、高剂量组与模型组比较有统计学意义(P<0.05)。TTC染色结果显示人参皂苷Rg2低、中、高剂量能显著减少梗死面积,与模型组相比,差别有显著性(P<0.01)。Ach E组织化学染色可见人参皂苷Rg2高、中剂量组大鼠基底前脑Ach E阳性神经元数目与模型组比较差别有显著性(P<0.01),人参皂苷Rg2各组和尼莫地平组Ach E活性明显高于模型组,差别有统计学意义(P<0.01)。结论人参皂苷Rg2可通过减少缺血再灌注大鼠神经功能评分,减少脑梗死面积,提高胆碱能神经活性,对脑缺血再灌注损伤具有防护作用。  相似文献   

6.
Although the huge economic and social impact and the predicted incidence increase, neuroprotection for ischemic stroke remains as a therapeutically empty niche. In the present study, we investigated the rationale of the C-Phycocyanin (C-PC) treatment on global cerebral ischemia/reperfusion (I/R) injury in gerbils. We demonstrated that C-PC given either prophylactically or therapeutically was able to significantly reduce the infarct volume as assessed by triphenyltetrazolium chloride (TTC) staining and the neurological deficit score 24h post-stroke. In addition, C-PC exhibited a protective effect against hippocampus neuronal cell death, and significantly improved the functional outcome (locomotor behavior) and gerbil survival after 7 days of reperfusion. Malondialdehyde (MDA), peroxidation potential (PP) and ferric reducing ability of plasma (FRAP) were assayed in serum and brain homogenates to evaluate the redox status 24h post-stroke. The treatment with C-PC prevented the lipid peroxidation and the increase of FRAP in both tissue compartments. These results suggest that the protective effects of C-PC are most likely due to its antioxidant activity, although its anti-inflammatory and immuno-modulatory properties reported elsewhere could also contribute to neuroprotection. To our knowledge, this is the first report of the neuroprotective effect of C-PC in an experimental model of global cerebral I/R damage, and strongly indicates that C-PC may represent a potential preventive and acute disease modifying pharmacological agent for stroke therapy.  相似文献   

7.
目的探讨bFGF对大鼠脑缺血再灌注损伤后神经细胞凋亡和脑组织中SOD、MDA含量变化的影响。方法应用线栓法制作大鼠局灶性脑缺血再灌注模型,大脑中动脉阻塞1h再灌注损伤24h,检测假手术组、缺血再灌注组和bFGF组的凋亡细胞数和脑组织中SOD、MDA的含量。结果假手术组偶见凋亡细胞,缺血再灌注组和bFGF组凋亡细胞数分别是26.35±5.67和18.65±5.91,与缺血再灌注组相比,bFGF组缺血区皮质凋亡神经元明显减少(P<0.05)。SOD,MDA测定结果显示三组间比较,具有显著性差异(P<0.01和P<0.05)。结论抗氧化作用可能是bFGF减少大鼠脑缺血再灌注损伤后细胞凋亡的分子机制之一。  相似文献   

8.
抗白细胞药物在大鼠局灶性脑缺血中的保护作用   总被引:8,自引:1,他引:8  
目的研究抗白细胞药物:环磷酰胺、氯化奎宁、秋水仙碱在大鼠局灶性脑缺血中的作用。方法用线栓法建立大鼠大脑中动脉区缺血再灌注模型,检测抗白细胞药物对大鼠局灶性脑缺血后外周血白细胞总数,梗塞区小胶质细胞数及对梗塞体积的影响。结果三种抗白细胞药物均能抑制外周血白细胞活化和梗塞区小胶质细胞的激活,缩小梗塞体积。结论抗白细胞药物对缺血性脑梗塞有保护作用,且联合用药优于单一用药  相似文献   

9.
bFGF对大鼠局灶性缺血再灌注脑组织的保护作用   总被引:2,自引:0,他引:2  
  相似文献   

10.
Simple regulation of c-Jun N-terminal kinase(JNK) or p38 mitogen-activated protein kinase(MAPK) pathways is not enough to trigger cell apoptosis.However,activation of the stress activated pathway(JNK/p38 MAPK) together with inhibition of the growth factor activated extracellular signal-regulated kinase(ERK) pathway can promote cell apoptosis.We hypothesized that inhibition of the JNK or p38 pro-apoptotic pathway and activating the ERK pathway could be the mechanism of anti-apoptosis following cerebral ischemia/reperfusion injury.To investigate the mechanism of the protective effect of electroacupuncture on cerebral ischemia/reperfusion injury in JNK knockout mice,mouse models of cerebral ischemia/reperfusion injury were established by Longa's method.Electroacupuncture was conducted at acupoints Chize(LU5),Hegu(LI4),Sanyinjiao(SP6) and Zusanli(ST36) 1.5 hours after ischemia/reperfusion injury for 20 minutes,once a day.The neurological function was evaluated using neurological deficit scores.The expression of phospho-extracellular signal-regulated kinase(p-ERK) and phospho-p38(p-p38) in JNK knockout mice was detected using double-labeling immunofluorescence and western blot assay.The m RNA expression of ERK and p38 was measured by quantitative real-time polymerase chain reaction.Electroacupuncture improved neurological function,increased the immunoreactivity and relative expression of p-ERK and reduced that of p-p38 in the cerebral cortex and hippocampus on the injured side.Electroacupuncture increased m RNA expression of ERK,but decreased that of p38 in the cerebral cortex and hippocampus on the injured side.In conclusion,electroacupuncture upregulated the protective ERK pathway and inhibited the pro-apoptotic p38 pathway,thereby exerting a neuroprotective effect and improving the neurological function in JNK knockout mice.  相似文献   

11.
目的观察ATP敏感性钾通道(KATP)开放剂尼可地尔(nicorandil)对大鼠脑缺血/再灌注(I/R)损伤的保护作用及其机制。方法将60只雄性Wistar大鼠随机分为4组:A组(假手术组)、B组(脑缺血再灌注组)、C组(脑缺血再灌注+尼可地尔组)及D组(脑缺血再灌注+尼可地尔+5-HD组),采用线栓法建立大鼠大脑中动脉闭塞(MCAO)模型,各组于脑缺血2h后进行再灌注,再灌注22h后观察各组大鼠神经功能评分、脑梗死体积、线粒体标志酶活性和脂质过氧化降解产物丙二醛(malondialdehyde,MDA)的含量。结果(1)B、C、D组再灌注22h后神经功能评分显著低于A组,脑梗死体积、脂质过氧化物MDA含量均显著高于A组,线粒体标志酶活性SDH、CO表达显著低于A组(P〈0.01);(2)与B、D组比较,C组神经功能评分明显升高,脑梗死体积、MDA含量明显减少,SDH、CO活性明显增高(P〈0.01);(3)B组和D组各指标之间比较差异均无显著性(P〉0.05)。结论尼可地尔对大鼠脑缺血再灌注损伤具有保护作用,其机制可能与开放mitoKATP通道、维护线粒体功能、减少氧自由基产生有关。  相似文献   

12.
神经节苷脂对大鼠脑缺血再灌注损伤的脑保护作用   总被引:6,自引:1,他引:6  
目的探讨神经节苷脂对大鼠脑缺血再灌注损伤的脑保护作用。方法采用线栓法制作缺血再灌注大鼠模型,分别用神经节苷脂(治疗组)和生理盐水(对照组)腹腔注射。观察两组大鼠缺血90min、缺血90min再灌注24h的脑梗死面积、神经功能缺损程度、细胞凋亡数、细胞凋亡率。结果治疗组大鼠于相同时间点脑梗死面积较对照组明显减小,仅表现轻度的神经功能缺损,且神经细胞的凋亡数较对照组显著减少(均P<0.01)。结论神经节苷脂能明显减小大鼠实验性脑缺血的脑梗死面积,减轻脑缺血再灌注后神经功能缺损程度,显著减轻缺血区神经元损害,具有显著的脑保护作用。  相似文献   

13.
Rutaecarpine,an active component of the traditional Chinese medicine Tetradium ruticarpum,has been shown to improve myocardial ischemia reperfusion injury.Because both cardiovascular and cerebrovascular diseases are forms of ischemic vascular disease,they are closely related.We hypothesized that rutaecarpine also has neuroprotective effects on cerebral ischemia reperfusion injury.A cerebral ischemia reperfusion model was established after 84,252 and 504 μg/kg rutaecarpine were given to mice via intraperitoneal injection,daily for 7 days.Results of the step through test,2,3,5-triphenyl tetrazolium chloride dyeing and oxidative stress indicators showed that rutaecarpine could improve learning and memory ability,neurological symptoms and reduce infarction volume and cerebral water content in mice with cerebral ischemia reperfusion injury.Rutaecarpine could significantly decrease the malondialdehyde content and increase the activities of superoxide dismutase and glutathione peroxidase in mouse brain.Therefore,rutaecarpine could improve neurological function following injury induced by cerebral ischemia reperfusion,and the mechanism of this improvement may be associated with oxidative stress.These results verify that rutaecarpine has neuroprotective effects on cerebral ischemia reperfusion in mice.  相似文献   

14.
水通道蛋白4在大鼠脑缺血再灌注损伤中的作用   总被引:5,自引:1,他引:5  
目的研究水通道蛋白4(AQP4)在缺血再灌注损伤大鼠脑内表达及作用。方法以大脑中动脉线栓法建立大鼠缺血再灌注模型,采用干湿法测定模型的脑组织含水量及伊文氏蓝含量;免疫蛋白印记(WesternBlot)技术分析在缺血再灌注不同时程脑内AQP4的表达情况,以及AQP4与脑含水量和伊文氏蓝水平的相关性,并与对照组比较。结果与对照组相比,实验组大鼠脑组织含水量及伊文氏蓝水平在缺血再灌注后不同时间点明显高于对照组(P<0.05~0.01);AQP4蛋白表达明显增高(均P<0.05),并随着缺血再灌时间的延长,其表达量亦逐渐增加,在再灌后24~48h达到高峰。缺血再灌注后AQP4脑内的表达与脑组织含水量及伊文氏蓝水平呈正相关(r=0.38、r=0.45,均P<0.05)。结论AQP4的高表达参与了脑缺血再灌注后继发的血脑屏障的开放和脑水肿的发生,是脑水肿产生的重要分子基础。  相似文献   

15.
BACKGROUNG: Cerebral schemia may result in cerebral edema and neuronal injury by activating some endogenous mechanisms. It has been confirmed that picrosideⅡ could protect neuronal damage in vitro an ex vitro. OBJECTIVE: The aim of the present study is to explore the neuroprotective effects and the perfect treatment window of picrosideⅡ on brain insult in rats following middle cerebral artery occlusion and reperfusion (MCAO/R). DESIGN, TIME AND SETTING: A randomized, controlled animal experiment was performed at Institute of Cerebrovascular Diseases, Qingdao University Medical College from September 2008 to May 2009. MATERIALS AND METHODS: One hundred and sixty-five adult healthy male Wistar rats were randomly divided into a sham-operation group (n=15), a control group (n=75) and a treatment group (n=75). Rats in the control group and the treatment group were experimented surgery operation of MCAO/R with an intraluminal monofilament suture from left external-internal carotid artery. Those in the treatment group were injected 1.0% picrosideⅡat a single dosage of 10mg/kg from the tail vein. We evaluated neurological function score by Longa’s method, cerebral infarction volume with tetrazolium chloride (TTC) stain. Then we compared cell apoptosis by terminal deoxynucleotidyl transference-mediated biotinylated deoxyuridine triphosphate nick end labeling technique (TUNEL), and determined the expression alternation of aquaporin-4 (AQP-4) via fluorescence labeling analysis and RT-PCR technique. RESULTS: After MCAO/R, neurological function scores were decreased, and a small infarction focus could be detected in ischemic cortex in the control group at ischemic 0.5h, along with the increased number of positive-apotosis cells and the elevated expression of AQP-4 mRNA and its protein. With the duration of ischemia, neurological scores and infarction sizes obviously increased in the control group during ischemic 1.0h-2.0h. A great deal of positive-apoptotic cells were widespread in the cortex and the striatum in the ischemic ipsilateral. Simultaneously, the expression of AQP-4 mRNA and its protein increased to some extent. PicrosideⅡ treatment significantly improved the loss of neurological function, decreased the infarction volume, and elevated the expression levels of AQP-4 mRNA and its protein compared with those in the control group. The therapeutic effect of picrosideⅡ was notable, especially in the ischemic 1.0h subsection. CONCLUSION: These results demonstrate that picrosideⅡ played a neuroprotective effect on cerebral ischemic reperfusion by inhibiting apoptosis and regulating the expression of AQP-4 mRNA and its protein. The best therapeutic window is at ischemic 1h after MCAO.  相似文献   

16.
目的 探讨Kallikrein基因对脑缺血再灌注后梗死灶周围血管增生与局部脑血流灌注恢复的作用.方法 建立大鼠脑缺血再灌注模型,术后将90只大鼠按照随机数字表法分为3组.每组30只,分别是空白对照组、注射生理盐水、注射pAdCMV-人组织激肽释放酶(HTK)组.各组大鼠又分为治疗后12 h、24 h及72 h组,每组各10只.治疗前后行大鼠神经功能缺损评分.TTC染色方法测定脑梗死面积的变化,用免疫组化检测外源性HTK的表达以及局部血管内皮生长因子(VEGF)的表达,并通过14C-iodoantipyrine微示踪技术检测局部脑血流灌注(rCBF)情况.结果 与其他两组相比,pAdCMV-HTK组大鼠脑梗死面积在治疗后24h已有明显减小,72h后这种变化更明显,差异有统计学意义(P<0.05);在治疗后24 h,pAdCMV-HTK组大鼠神经功能缺损评分明显低于生理盐水组及空白对照组,治疗后72h差异更明显,差异有统计学意义(P<0.05).vEGF阳性细胞主要分布于脑梗死灶周边皮质与部分白质;pAdCMV-HTK组VEGF表达在治疗后12h、24h、72h均明显高于生理盐水组及空白对照组,差异有统计学意义(P<0.05).各组缺血再灌注后脑梗死灶周围白质与皮质rCBF均较对侧稍减少:pAdCMV-HTK组治疗后12h,梗死灶周围白质与皮质rCBF较空白对照组与生理盐水组有增高.但不明显,差异无统计学意义(P>0.05),而在治疗24h、72 h后rCBF则明显增高,差异有统计学意义(P<0.05).结论 在脑缺血再灌注后,Kallikrein基因转导可增加梗死灶周围脑组织的血管增生,改善rCBF,减小梗死面积,从而达到保护缺血神经细胞功能的作用.  相似文献   

17.
Ephedrine has protective effect to rats suffered from cerebral ischemia, the aim of the present study was to evaluate the side effects of ephedrine on heart, liver, kidney and cerebrum of rats after ischemic-reperfusion. Sprague-Dawley (SD) rats, suffered from ischemic-reperfusion were randomly divided into 4 groups: A group for ephedrine, B group for ephedrine, C group for ephedrine, and control group (D group).At each week, hematoxylin eosin staining was used to observe the tissue of all the organs, then, the blood pressure, aspartate aminotransferase (AST), alkaline phosphatase (AKP) and creatinine were tested, also immunohistochemical method was used to test the expression of brain-derived neurotrophic factor (BDNF) on hippocampal CA3 area. The blood pressure values were lower in ephedrine groups than those in control group all the time (P<0.05). The biochemistry results showed that AST、AKP and serum creatinine in ephedrine groups were higher than those in control groups (P<0.05). The expression levels of BDNF on hippocampal CA3 area in ephedrine groups were higher than that in control group at the last three weeks (P<0.05). The pathological section showed that in all the ephedrine groups, we can see congestion, degeneration and edema of tissues. These findings indicate that ephedrine may have side effects on heart, liver, kidney and cerebrum in ischemic/reperfusion rats. There may be correlation between the side effects and dose, the side effects are enhanced with an increased dose of ephedrine. The injury of the above organs also may be transient, which can be recovered after discontinuation of treatment.  相似文献   

18.
目的 探讨银杏叶提取物EGb761对大鼠局灶性脑缺血再灌注损伤的保护作用及其机制.方法 制作大鼠右侧大脑中动脉闭塞再灌注模型.将30只清洁级雄性SD大鼠随机分为3组,即假手术组(n-10):给予5 ml生理盐水腹腔注射;对照组(n-10):缺血90 min,再灌注24 h,5 ml生理盐水腹腔注射;实验组(n-10):缺血90 min,再灌注24 h,在再灌注即刻20 mg/kg银杏叶提取物生理盐水稀释成5 ml腹腔注射.再灌注24 h后采用四分法测定大鼠的神经功能障碍评分(NDS);实验结束后断头取脑采用TTC染色法测定脑梗死面积(以其同侧大脑半球体积的百分比表示);采用western blot测定脑组织微管相关蛋白2(MAP2)的表达水平.结果 与假手术组比较,对照组、实验组小鼠NDS评分均显著升高,分别为(2.49±0.85)分和(1.58±0.62)分,3组间比较差异均明显(P<0.05);对照组、实验组脑梗死面积均显著增大(P<0.05),实验组脑梗死面积较对照组显著减小(P<0.05);与假手术组比较,与假手术组比较,对照组、实验组缺血侧MAP2蛋白的表达水平均显著降低(P<0.05),实验组缺血侧MAP2蛋白的表达水平较对照组显著升高(P<0.05).结论 银杏提取物EGb761对大鼠局灶性脑缺血再灌注损伤具有显著的保护效应,其效应与MAP2蛋白表达水平升高有关.  相似文献   

19.
目的探讨丁苯酞(NBP)预处理对脑缺血再灌注损伤后大鼠海马神经元的保护作用。方法将120只SD大鼠随机分为假手术组、缺血再灌注组、NBP低剂量预处理组(低剂量组)、NBP中剂量预处理组(中剂量组)和NBP高剂量预处理组(高剂量组),每组24只大鼠。低、中、高剂量组大鼠分别给予20 mg/kg、40 mg/kg、80 mg/kg NBP预处理。采用改良Zea Longa线栓法制备脑缺血再灌注模型。2%氯化三苯基四氮唑(TTC)染色测量梗死体积,免疫组织化学法观察5-羟色胺(5-HT)阳性细胞数,免疫印迹法检测5-HT蛋白水平。结果 NBP低剂量组、中剂量组、高剂量组脑梗死体积显著小于缺血再灌注组(均P0.05)。中剂量组与高剂量组脑梗死体积显著小于低剂量组(均P0.05)。与假手术组比较,缺血再灌注组大鼠海马中5-HT阳性细胞数及蛋白表达明显降低(均P0.01)。与缺血再灌注组比较,NBP低、中、高剂量组的5-HT阳性细胞数及蛋白表达显著增加(均P0.05)。中剂量组与高剂量组5-HT阳性细胞数及蛋白表达显著高于低剂量组(均P0.05),高剂量组与中剂量组差异无统计学意义。结论丁苯酞预处理具有脑保护作用,其机制可能为上调缺血海马半暗带区5-HT表达。  相似文献   

20.
鼠脑缺血再灌注损伤炎症反应及环磷酰胺影响   总被引:8,自引:0,他引:8  
目的 探讨脑缺血再灌注不同缺血区域炎症反应特点及环磷酰胺影响.方法 将大鼠随机分为假手术组、对照组、环磷酰胺预处理组,建立局灶性脑缺血再灌注模型.用免疫组化法和生化法观察额顶部皮质和基底节区P-选择素表达、髓过氧化物酶(MPO)活性变化;并进行TTC染色和HE染色.结果 (1)再灌注3h缺血侧额顶部皮质和基底节区出现P-选择素表达,12h达高峰.环磷酰胺预处理组和对照组相比较,差异无显著性(P>o.05).(2)再灌注12h以后MPO活性明显升高.基底节区的MPO活性在再灌注48h达到高峰后下降.额顶部皮质MPO活性在再灌注24h达到高峰后至96h仍维持较高水平.和对照组相比较,环磷酰胺预处理组MP(活性升高受抑制(P<0.05).(3)环磷酰胺预处理可显著缩小脑梗死体积(P<0.05).结论 (1)脑缺血再灌注损伤存在主动性炎症反应,额顶部皮质比基底节区的炎症反应更持久和剧烈.(2)环磷酰胺减少缺血侧中性粒细胞浸润数量,具有神经保护作用,但不直接影响P-选择素的表达.  相似文献   

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