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271.
272.
AIM: To Study the influence of plasma TG level on the contents of serum HDL subpopulations. METHODS: Classified by the contents of serum TG, the serum level of HDL subpopulations in 106 normal TC and 183 high TC subjects were analyzed by two-dimensional gel electrophoresis coupled with immunodection method. RESULTS: The apo-AⅠcontents of per-β1-HDL, HDL3c, HDL3b and HDL3a were higher in a certain extent in TC high subjects vs corresponding TC desirable subjects. The apo-AⅠ contents of per-β1-HDL (in borer-line high TG subgroup) and HDL3b (in very high TG subgroup) were significantly higher (P<0.05 or P<0.01), while the apo-AⅠ contents of HDL2b and HDL2a were all lower in TC high subjects vs corresponding TC normal subjects. With the increase in plasma TG levels, the apoA-Ⅰ content of pre-β1-HDL increased, and it was significantly higher (P<0.05 or P<0.01) in borderline-high TG(except TC desirable subjects), high TG and very high TG subgroups vs corresponding normal TG subgroup. Contents of HDL3b and HDL3a had the same tendency, and in TC high subjects contents of HDL3b (in very high TG subgroup) and HDL3a (in every subgroups, in which levels of TG were higher) were significantly higher (P<0.05 and P<0.01) than in normal TG subgroup. On contrast, the apoA-Ⅰcontents of HDL2b and HDL2a following with the increase of plasma TG levels tended to become lower. Contents of HDL2b were significantly lower (P<0.05) in high TG subgroup and very high TG subgroup vs corresponding normal TG subgroup, and in TC high subjects contents of HDL2a were significantly lower (P<0.05) in very high TG subgroups vs normal TG subgroup. CONCLUSION: Our data show the general shift toward smaller size of HDL particle size with the increase in TC and TG levels. Contents of TC and TG are very important to contents of HDL subclasses.  相似文献   
273.
A cpDNA fragment of 34 genotypes belonging to Citrus and four related genera was amplified and sequenced. Chloroplast microsatellites were revealed with the length of repeats ranging from 25 to 44 bases. Other than the normal uninucleotide poly(A) repeats, a trinucleotide poly(TAA) motif was also found, the first report of such repeats in a plant chloroplast genome. According to SSR structure variations, 18 Chloroplast SSR Types (CST) were identified. The CST sequences were informative for better understanding the genetic relationships of chloroplast genomes among the analyzed genotypes and confirmed some previous hypotheses about the female parent of several hybrid accessions.  相似文献   
274.
AIM: To examine the expression of alpha-smooth muscle actin in scar tissue, and observe the phenomenon of apoptosis and its involvement in the process of pathological scarring and the presence of myofibroblasts or absence of cell in the dermis. To investigate the potential role of reparative cell apoptosis in hyperplastic scar formation. METHODS: The samples of scar were obtained from post-burn patients undergoing plastic operation in our burn unit recently, and the samples of control came from skin donor site of the same patient correspondingly. TUNEL assays were performed to evaluate the number of apoptotic cells in scar versus normal skin. In situ hybridization and immunohistochemistry staining technique were employed to determine the expression of different dermis cells markers in scar tissue and normal skin. RESULTS: There existed evident difference in apoptotic cells in the dermis between scars tissue and normal human skin. The expression positive cells were much more in hyperplastic scars than that in normal human skin; the apoptotic cells of proliferative stage were slight more than that of mature stage. However, in proliferative stage, the number of apoptotic cells was higher for the combination of hyperplastic scar than normally healed flat scars. But in mature stage, no obviously difference was detected between hyperplastic scar and normally healed flat scar. The monoclonal anti-α smooth muscle actin (ASMA) expression was significantly stronger in proliferative stage than that of mature stage. CONCLUSIONS: With reconstitution of dermal tissue, myofibroblasts containing alpha-SM actin disappear under normal wound healing, probably as a result of apoptosis. The myofibroblast play a critical role in wound closure and in the pathologic sequelae of healing.  相似文献   
275.
研究表明M_9中间砧段对~(32)P有明显的滞阻作用,生长期限制~(32)P上运,休眠期限制下运。中间砧段内滞存~(32)P较多,影响基砧根系的吸收,试验树全株~(32)P含量低于对照树,抑制了植株接穗部分的营养生长。  相似文献   
276.
以4个生产上常用的灵芝(Ganoderma lucidum)菌株为亲本,用原生质体单核化技术获取单核体材料,按4个组合在不同亲本的单核体间配对杂交,以锁状联合为细胞标记共选出17个杂交子,比较了这些杂交子的菌丝生长速度、摇瓶培养菌丝的三萜和总糖量,为后继的育种工作提供亲本材料选择基础.  相似文献   
277.
应用RAPD、SRAP及AFLP标记构建荔枝高密度复合遗传图谱   总被引:5,自引:0,他引:5  
以荔枝(Litchi chinensis Sonn.)特迟熟品种‘马贵荔’为母本,特早熟品种‘焦核三月红’为父本,杂交获得F1群体,利用该群体的76个单株为作图群体,连同两个亲本,进行了RAPD、SRAP和AFLP分子标记分析,并运用Joinmap3.0进行连锁分析,分别构建了‘马贵荔’和‘焦核三月红’的分子遗传图谱,其中‘马贵荔’的遗传图谱为20个连锁群,包含238个标记位点,覆盖总图距1 096.59 cM,位点间平均遗传距离为4.61 cM;焦核三月红的遗传图谱为19个连锁群,包含239个标记位点,覆盖总图距881.36 cM,位点间平均遗传距离为3.69 cM。  相似文献   
278.
丽蚜小蜂已被广泛应用于设施蔬菜烟粉虱的防治,在张家港市进行释放丽蚜小蜂防治番茄烟粉虱试验。结果表明,日平均温度20℃时,烟粉虱虫口数开始增长,到23℃烟粉虱虫口数增长显著加快;丽蚜小蜂的放蜂虫口指标为0.5~1头/株,前期虫口基数较低时,采取少量多次的释放方法,在放蜂51 d后防治效果最好,为69.22%;与对照区相比,丽蚜小蜂可显著控制烟粉虱的虫口数增长;日平均温度20~23℃为烟粉虱的防治重点时期,在此期间适当增加丽蚜小蜂蜂卡的释放量,可提高后期丽蚜小蜂对烟粉虱虫口数的防治效果;对烟粉虱的防治应侧重于植株的中上部,下部叶片可采取打老叶的方式降低虫口数。  相似文献   
279.
AIM: To investigate the role of nitric oxide synthase (NOS), soluble guanylyl cyclase (sGC) and protein kinase C (PKC) signaling in tumor necrosis factor-α (TNF-α)-induced cardioprotection against hypoxia/reoxygenation (H/R) injury. METHODS: Neonatal rat ventricular myocytes were pretreated with TNF-α or sodium nitroprusside (SNP) or L-arginine (L-Arg), respectively, for 12 h and then subjected to continuous hypoxia for 12 h, followed by reoxygenation for 6 h. The manganese superoxide dismutase (Mn-SOD) activity of the cells was measured after H/R. Myocyte injury was determined by the release of lactic dehydrogenase (LDH). RESULTS: TNF-α (105 U/L) significantly increased the Mn-SOD activity and decreased release of LDH from ventricular myocytes. The cardioprotection against H/R injury was induced by the pretreatment with SNP (5 μmol/L) or L-Arg (5 mmol/L), which was blocked by ODQ (10 μmol/L), the specific sGC inhibitor, and Chel (5 μmol/L), the specific PKC inhibitor. Pretreatment with L-NAME (100 μmol/L), ODQ, Chel, antoxidant 2-MPG (400 μmol/L) or tyrosine kinase inhibitor genistein (50 μmol/L) attenuated the increased Mn-SOD activity and reduced LDH level induced by TNF-α. CONCLUSION: The results suggest that NO may play a role in TNF-α-induced cardioprotection, which is mediated by sGC and PKC.  相似文献   
280.
紫花地丁组培快繁技术研究   总被引:1,自引:0,他引:1  
以紫花地丁的茎尖为外植体进行组织培养研究,结果表明:外植体用70%酒精处理30 s,0.1% HgCl2处理6 min效果最佳;最佳生长和增殖培养基为:MS BA 3 mg/L NAA 0.1 mg/L;最佳生根培养基为:1/2 MS BA 0.3 mg/L AC 0.3 g/L,生根率达100%.  相似文献   
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