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21.
针刺对去卵巢大鼠脑内胆碱乙酰转移酶基因表达的影响   总被引:3,自引:0,他引:3  
Tian SJ  Yin L  Sun JP  Tian QH  Zu YQ  Zheng Y  Li Y  Li YR 《生理学报》2004,56(4):498-502
本工作旨在探讨雌激素对脑内乙酰胆碱生成的影响和电针刺激“足三里”穴对去卵巢大鼠脑内乙酰胆碱生成的调整作用。实验选用成年Wistar雌性大鼠,将动物分为正常对照组(INT)、去卵巢组(OVX)和去卵巢针刺组(OVX AC)。用放射免疫分析方法测定血中雌二醇含量,采用RT-PCR方法获得大鼠脑内胆碱乙酰转移酶(ChAT)mRNA的逆转录表达产物——cDNA,用琼脂糖凝胶电泳方法检测,并通过原位杂交方法观察海马ChAT mRNA阳性神经元的表达,然后用计算机图像分析系统进行统计分析。实验结果显示:去卵巢组大鼠体内雌激素水平明显降低,脑内ChAT mRNA的RT-PCR产物和海马ChAT mRNA阳性表达产物的平均面积、平均积分光度值均明显减少,与对照组和针刺组比较有显著性差异;去卵巢针刺“足三里”穴组与去卵巢组相比,大鼠血中雌激素水平明显升高,脑内ChAT mRNA RT-PCR产物明显增多,海马的ChAT mRNA表达阳性神经元增多。以上结果提示:脑内ChAT基因表达与体内雌激素水平有密切关系,去卵巢后针刺“足三里”穴对ChAT的调节作用可能是针刺增强脑内乙酰胆碱含量的机制之一。  相似文献   
22.
This study was aimed at studying the effect of the induction of immune tolerance to swine cardiac myosin from anti-L3T4 monoclonal antibody injection and whether the immune tolerance could protect mice with myosin-induced myocarditis from myocardial injury. Twenty-four Balb/c mice were divided into two groups at random. All of the mice were immunized with swine cardiac myosin on the 1st day, 14th, 28th, 42nd, and 52nd day. Immune tolerance was induced by triplicate injections of 400 microg anti-L3T4 McAb on the 0 day (intravenous), 1st day, and 2nd day (intraperitoneal) in McAb-treated group. In the saline-treated group, saline of the same volume as anti-L3T4 monoclonal antibody was used as a control. The sera and hearts biopsies of all mice were collected on the 58th day. The anti-cardiac myosin antibody was examined with ELISA, and pathological changes of heart were observed by light microscope. It was shown that mice immunized with swine cardiac myosin could produce anti-myosin antibody and the anti-cardiac myosin antibody was positive in most of the saline-treated group but negative in the McAb-treated group. Morphologically, myocardial degeneration, necrosis, and infiltration of inflammatory cells were found in the saline-treated group but not in the McAb-treated group. In conclusion, this study indicated that the immune tolerance to cardiac myosin was induced by the anti-L3T4 monoclonal antibody, and accordingly myocardial injury could be prevented by induction of immune tolerance.  相似文献   
23.
Conchological, anatomical and genetic characteristics werecompared among several populations of the Biomphalaria havanensis complexfrom Cuba and other localities in the Caribbean region. Two morphometricmeasures (height and diameter) distinguished two closely similarmorphs of the shell. The reproductive system also separated thesemorphs, particularly upon comparison of sizes of the penis sheathand the preputium. The two morphological groups differed in9 to 12 fixed alleles according to population. Further allozymicdata analyzed in the present work confirmed this difference.The results strongly support the assumption that the B. havanensis complexincludes two distinct species: B. havanensis, for which thetype locality is the swampy area near the vicinity of Havana,Cuba and Biomphalaria sp. a species which commonly occurs inCuba and in Dominican Republic. The taxonomic identity of Biomphalariasp. is discussed. (Received 28 January 2000; accepted 15 August 2000)  相似文献   
24.
Xylitol production from corncob hemicellulose is a popular process in China. Microbial conversion of xylose to xylitol, as a biological process with many advantages, has drawn increasing attention. As a by-product from the manufacturing of xylitol, corncob cellulosic residues are produced in very large amounts and represent an environmental problem. As a result, considering the large amount of xylitol production in China, the conversion of corncob cellulosic residues has become a widespread issue having to be tackled. After the hemicellulose in corncob has been hydrolyzed for xylitol production, the corncob cellulosic residue is porous and can easily be hydrolyzed by cellulases into glucose and further converted to ethanol, another high-added-value chemical. Based on the latest technology advancements in xylitol, cellulase, and ethanol production, the integrated production of ethanol from corncob cellulosic residues appears as a promising way to improve the profit of the whole xylitol production process.  相似文献   
25.
杉木人工林冰雪灾害受灾和萌生情况调查及影响因子分析   总被引:3,自引:0,他引:3  
以九龙山国家级自然保护区的主要公益林杉木人工林作为研究对象,选择具有代表性的受灾区域,自海拔700 m至900 m设置样地,共10块样地,总面积4 000 m2。分析其受2008年初严重冰雪灾害破坏及灾后萌生情况与胸径、树高、尖削度、海拔之间的关系。结果表明: 1)杉木人工林损害严重,其中断冠、断干植株比例较高,而掘根和冻死植株相对较少;杉木具有极强的萌生能力,以断冠杉木的萌生能力最强。2)不同胸径、树高、尖削度的杉木对于冰雪灾害的抵御能力及萌生能力存在一定差异,小径级矮小的个体受灾较重,易被冻死和掘根,大径级的较高个体受灾相对较轻,主要表现为断冠和断干危害,且不同径级下的受灾杉木上部萌生均占较大比例。3)杉木的抵御能力和萌生能力与海拔存在一定的关系,高海拔地区杉木受灾较重,而中海拔地区的杉木萌生能力相对较强。  相似文献   
26.
酶法制备功能性纤维低聚糖的研究   总被引:1,自引:0,他引:1  
研究里氏木霉(Trichoderma reesei)Rut C30纤维素酶单一组分EGI、EGII和CBHI降解纤维素的机理及纤维低聚糖酶法制备技术,进而初步研究纤维低聚糖对青春双歧杆菌的增殖作用。以内切葡聚糖酶EGII酶法制备纤维低聚糖,每克纤维素最佳酶用量1 U,最佳酶解时间90 min,制备得到的纤维低聚糖中纤维二糖、纤维三糖和纤维四糖占总糖的比例分别为43.8%、34.8%和7.9%。以纤维二糖、纤维低聚糖为C源增殖青春双歧杆菌,菌体质量浓度增殖倍数分别为2.14、2.84。  相似文献   
27.
里氏木霉与黑曲霉混合发酵产纤维素酶及其水解特性   总被引:2,自引:0,他引:2  
研究了利用里氏木霉和黑曲霉混合培养产纤维素酶,以黑曲霉孢子悬浮液的不同活化浓度及不同的活化时间来寻找2个菌种发挥最大协同作用的结合点以及所产纤维素酶的水解特性。以里氏木霉单一培养和黑曲霉单一培养为参照进行对比研究。底物为农林废弃物之一的玉米秸秆,经过蒸气爆破预处理后,用作产酶C源。结果表明:黑曲霉孢子悬浮液活化浓度为10个/mL,活化时间为12 h时,滤纸酶比酶活最高,达3.32 U/mL,高于里氏木霉单一培养的2.25 U/mL,β-葡萄糖苷酶比酶活达1.32 U/mL,高于里氏木霉单一培养的0.57 U/mL。为进一步验证混合菌产纤维素酶的水解效果,利用混合菌产纤维酶的酶液及里氏木霉产纤维素酶的酶液进行酶水解实验,当酶用量为20 U/g绝干纤维素,底物质量浓度为100 g/L条件下水解48 h,混合菌所产酶液酶解得率达70.00%,高于里氏木霉所产酶液的酶解得率63.05%。实验表明里氏木霉与黑曲霉混合培养产酶是可行的,并优于单一菌种培养。  相似文献   
28.
本研究旨在检测男性尿道炎患者中尿道多形核白细胞数量,并进行解脲脲原体(Uu)培养,以评价非淋病奈瑟菌性尿道炎的临床意义。将2284例男性性病患者的尿道分泌物涂片,亚甲蓝(美蓝)染色后镜检多形核白细胞,并体外培养尿道分泌物的Uu。结果显示,645例患者(28.2%)Uu培养阳性,其中158例(24.5%)≥5个多形核白细胞,157例(24.3%)1~4个多形核白细胞,330例(51.2%)无多形核白细胞。218例阳性患者(33.8%)无症状,614例阳性患者(95.2%)无体征。男性尿道多形核白细胞数量在Uu培养阳性和阴性患者中存在显著差异(P0.01)。结果提示临床诊断与实验室检查在证实男性非淋病奈瑟菌性尿道炎中具有重要意义。  相似文献   
29.
1. This study evaluates the efficacy of remote sensing technology to monitor species composition, areal extent and density of aquatic plants (macrophytes and filamentous algae) in impoundments where their presence may violate water‐quality standards. 2. Multispectral satellite (IKONOS) images and more than 500 in situ hyperspectral samples were acquired to map aquatic plant distributions. By analyzing field measurements, we created a library of hyperspectral signatures for a variety of aquatic plant species, associations and densities. We also used three vegetation indices. Normalized Difference Vegetation Index (NDVI), near‐infrared (NIR)‐Green Angle Index (NGAI) and normalized water absorption depth (DH), at wavelengths 554, 680, 820 and 977 nm to differentiate among aquatic plant species composition, areal density and thickness in cases where hyperspectral analysis yielded potentially ambiguous interpretations. 3. We compared the NDVI derived from IKONOS imagery with the in situ, hyperspectral‐derived NDVI. The IKONOS‐based images were also compared to data obtained through routine visual observations. Our results confirmed that aquatic species composition alters spectral signatures and affects the accuracy of remote sensing of aquatic plant density. The results also demonstrated that the NGAI has apparent advantages in estimating density over the NDVI and the DH. 4. In the feature space of the three indices, 3D scatter plot analysis revealed that hyperspectral data can differentiate several aquatic plant associations. High‐resolution multispectral imagery provided useful information to distinguish among biophysical aquatic plant characteristics. Classification analysis indicated that using satellite imagery to assess Lemna coverage yielded an overall agreement of 79% with visual observations and >90% agreement for the densest aquatic plant coverages. 5. Interpretation of biophysical parameters derived from high‐resolution satellite or airborne imagery should prove to be a valuable approach for assessing the effectiveness of management practices for controlling aquatic plant growth in inland waters, as well as for routine monitoring of aquatic plants in lakes and suitable lentic environments.  相似文献   
30.
目的:探讨本课题组收集家族性高胆固醇血症(FH)患者中存在低密度脂蛋白受体(LDLR)第13外显子(E13)基因突变患者临床生化和心血管系统损害特点.方法:对9例临床诊断为FH、基因检测到LDLR基因E13突变的患者进行回顾性分析.结果:(1)临床诊断FH纯合子患者7名,其总胆固醇(TC)水平15.12~26.14 mmol/L,杂合子患者2名,TC水平11.30~11.75 mrnol/L.(2)均可见不同程度黄色瘤;(3)FH纯合子3例心电图出现ST-T改变;4例儿童和1例青年患者出现瓣膜损害,冠脉血流储备(CVFR)减低;杂合子心电图检查均正常,1例出现瓣膜损害,CVFR均正常.(4)核苷酸序列分析证实:9例E13突变患者中,A606T纯舍突变3名;D601Y纯合突变2名;A606T+、W462X和A606T+D601Y复合杂合突变各1名;A606T和D601Y杂合突变各1名.结论:FH严重损害患儿心血管系统和皮肤,LDLR基因E13出现的A606T和D601Y突变可能成为中国FH人群的高频突变位点.  相似文献   
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