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1.
Li-hua Zhang Gong-fu Ye Yi-ming Lin Hai-chao Zhou Qi Zeng 《Journal of Zhejiang University. Science. B》2009,10(2):103-111
Seasonal dynamics of total phenolics (TP), extractable condensed tannins (ECT), protein-bound condensed tannins (PBCT), fiber-bound
condensed tannins (FBCT), total condensed tannins (TCT), and protein precipitation capacity (PPC) in young, mature and senescent
branchlets of Casuarina equisetifolia were studied at Chishan Forestry Center of Dongshan County, Fujian Province, China. In addition, nitrogen contents of branchlets
at the different developmental stages were also determined. The contents of TP and ECT, and PPC in young branchlets were significantly
higher than those in mature and senescent branchlets through the season. However, PBCT contents were significantly higher
in senescent branchlets than those in young and mature branchlets; FBCT fluctuated with season. Young branchlets had the highest
N content, which decreased during branch maturity and senescence. The highest contents of TP and the lowest contents of TCT
and N in young and mature branchlets were observed in summer. There was a significant negative correlation between TP and
N contents. In contrast, TCT contents were positively correlated to N contents. Nutrient resorption during senescence and
high TCT:N ratios in senescent branchlets are the important nutrient conservation strategies for C. equisetifolia.
Project supported by the National Eleventh Five-year Key Project (No. 2006BAD03A14-01), Fujian Provincial Major Special Program
of Science and Technology (No. 2006NZ0001-2), the Program for New Century Excellent Talents in University (No. NCET-07-0725),
and the Program for Innovative Research Team in Science and Technology in Fujian Province University, China 相似文献
2.
Tannins from Canarium album with potent antioxidant activity 总被引：1，自引：0，他引：1
The contents of total phenolics and extractable condensed tannins in the leaves,twigs and stem bark of Canarium album were determined.The structural heterogeneity of condensed tannins from stem bark was characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and nuclear magnetic resonance (NMR) analyses.The results show the predominance of signals representative of procyanidins and prodelphinidins.In addition,epicatechin and epigallocatechin polymers with galloylated procyanidin or prodelphinidin were also observed.The tannins were screened for their potential antioxidant activities using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing/antioxidant power (FRAP) model systems.Tannins extracted from leaves,twigs and stem bark all showed a very good DPPH radical scavenging activity and ferric reducing power. 相似文献
3.
杂交水稻离体叶片衰老与蛋白质代谢的关系 总被引：3，自引：0，他引：3
杂交水稻离体叶片衰老时，叶片中的叶绿素和蛋白质含量下降．游离氨基酸含量增加．氨肽酶和内肽酶的活性显著上升，说明在衰老叶片中氨肽醇和内肽酶的作用是蛋白质降解的主要原因． 相似文献
4.
瓣结鱼为水中垂直取食的温和肉食性鱼类．从140尾鱼（体长9．57-44．2cm）肠内含物分析,其食谱以水生昆虫及其幼、稚虫为主,该类食物出现率为99．29％,其次为螺、蚌等软体动物,出现率为15％．摄食强度有明显的季节性变化,以春季的3、4月最高,分别为93．33％和70．33％,5－7月较低,其它月份较为稳定．冬季以及生殖群体在繁殖季节无停食现象．该鱼的肠长／体长为1．21(N＝341）,其视觉在摄食中起重要作用． 相似文献
5.
Advanced primary peritoneal carcinoma： clinicopathological and prognostic factor analyses 总被引：1，自引：0，他引：1
Objective: To investigate the factors favoring a positive prognosis for advanced primary peritoneal carcinoma (PPC). Methods: Twenty-four cases meeting the criteria for PPC were analyzed retrospectively for the clinicopathologic profiles. Immunohistochemistry was used to determine the expressions of p53, Top2α, Ki-67 and Her-2/neu. Then all these clinicopathological factors and molecular markers were correlated with the prognosis. Results: There were 15 cases of primary peritoneal serous papillary carcinoma (PPSPC), 6 cases of mixed epithelial carcinoma (MEC) and 3 cases of malignant mixed Mullerian tumor (MMMT). All patients underwent cytoreductive surgery with optimal debulking achieved in 3 cases. Among those receiving first-line chemotherapy, 13 patients received the TP regimen (paclitaxel-cisplatin or carboplatin) and 7 patients received the PAC regimen (cisplatin-doxorubicin-cyclophosphamide). The median overall survival of all patients was 42 months, while the breakdown for survival time for patients with PPSPC, MMT and MEC was 44, 13 and 19 months, respectively. The expressions of p53, Top2a and Ki-67 were all demonstrated in 11 cases respectively. None showed the expression of Her-2/neu. There were significant differences in the median survival between patients with PPSPC and those with MMMT (44 months vs 13 months, P<0.05), also between patients receiving TP combination and those receiving the PAC regimen (75 months vs 28 months, P<0.05). Another significant difference in the median progression-free survival (PFS) was identified between patients with positive p53 immunostaining and those with negative p53 immunostaining (15 months vs 47 months, P<0.05), whereas age, menopausal status, residual tumor size and the other molecular factors did not significantly impact survival. Conclusion: Patients with PPC should be treated with a comprehensive management plan including appropriate cytoreductive surgery and responsive chemotherapy. Overestimating an optimal debulking surgery may not benefit survival. The pathologic subtype, chemotherapy regimen and p53 overexpression were significant prognostic factors. 相似文献
6.
7.
柴家荣 《昆明师范高等专科学校学报》2006,28(4):26-29
采用定期取样杀青烘干化验分析的方法，探索在不同N，P，K营养条件下白肋烟生长发育过程中的糖、氮、烟碱等化学物质变化规律，结果表明：总糖、还原糖随生长期推进呈增加趋势，而总氮、蛋白质呈下降趋势；随施N量增加各生长期的总氮、蛋白质、烟碱增加，而旺长、成熟期总糖和伸根、旺长前期、成熟期的还原糖下降；随施P量增加各生长期的总氮和伸根、旺长前期、成熟期的蛋白质、烟碱增加，而旺长期的总糖、旺长前期的还原糖和旺长后期的蛋白质、烟碱下降；随施K量增加各生长期的总氮、烟碱、蛋白质下降；N，K对总糖和还原糖，N，P对烟碱、总氛、蛋白质影响较大． 相似文献
8.
研究了23种红树植物（15种真红树植物,8种半红树植物）叶片衰老过程中氮（N）、磷（P）内吸收率.结果表明：（1）真红树植物与半红树植物相比,其叶片营养元素含量相对较低（Nmass=17.3mg/g;Pmass=1.4mg/g）,N、P含量随叶片衰老而减少;（2）大部分红树植物叶片氮磷比小于31,说明红树植物存在氮限制;（3）真红树植物氮内吸收率平均为63.6%,远高于半红树植物（52.2%）以及一般常绿植物（47.0%）,但真红树植物磷内吸收（53.4%）和半红树植物（49.4%）不存在显著的差异.因此,真红树植物拥有更高的氮保存能力,使其更适应于在缺氮环境下生存. 相似文献
9.
Leaf senescence is often caused by water deficit and the chimeric gene PSA612-1PT is an auto-regulated gene delaying leaf senescence. Using in vitro leaf discs culture system, the changes of contents of chlorophylls, carotenoids, soluble protein and thiobarbituric acid reactive substance （TBARS） and antioxidant enzymes activities were investigated during leaf senescence of PSA612-1PT modified gerbera induced by osmotic stress compared with the control plant （wild type）. Leaf discs were incubated in 20%, 40% （w/v） polyethylene glycol （PEG） 6 000 nutrient solution for 20 h under continuous light [ 130 μmol/（m^2·s）]. The results showed that the contents of chlorophylls, carotenoids and soluble protein were decreased by osmotic stress with the decrease being more pronounced at 40% PEG, but that, at the same PEG concentration the decrease in the transgenic plants was significantly lower than that in the control plant. The activities of superoxide dismutase （SOD）, catalases （CAT）, ascorbate peroxidase （APX）, guaiacol peroxidase （GPX） and dehydroascorbate reductase （DHAR） were stimulated by PEG treatment. However, the increases were higher in PSA612-IPT transgenic plants than in the control plants, particularly at 40% PEG treatment. Lipid peroxidation （TBARS content） was increased by PEG treatment with the increase being much lower in transgenic plant than in the control plant. It could be concluded that the increases in the activities ofantioxidant enzymes including SOD, CAT, APX, GPX and DHAR were responsible for the delay of leaf senescence induced by osmotic stress. 相似文献
10.
TCT检测及巴氏涂片细胞学检测在宫颈癌筛查中的对比研究 总被引：2，自引：0，他引：2
目的：对液基薄层细胞检测系统Thinprep Cytology Test（TCT）及The Bethesda System（TBS）细胞学分类法在宫颈癌筛查中的应用价值进行综合评价。方法：采用液基薄层细胞检测系统检测宫颈细胞并进行TBS细胞学分类诊断,将诊断意义不明的不典型鳞状细胞（ASCUS）以上病变均列为阳性病例,病例均在阴道镜下行活检,将细胞学检测结果与活检结果作对比分析。结果：对223例行TCT及阴道镜下活检与组织病理学诊断：鳞状细胞癌（SCC）100%（12/12）;高度病变88.23%（15/17）;低度病变88.44%（38/45）。结论：TCT技术应用于宫颈细胞涂片筛查,与传统的巴氏图片相比明显提高了涂片的满意率及宫颈异常细胞检出率。TBS报告方式内容直观、易懂、具体、客观,TCT检查异常的病例配合阴道镜病理检查进行诊断,能及早发现宫颈早期病变,尽可能防治宫颈癌发生。 相似文献
11.
INTRODUCTION Pond systems are commonly employed formunicipal sewage purification, especially in devel-oping countries, due to its cost-effectiveness andhigh potential of removing different pollutants. Un-fortunately, algae would bloom in the ponds andcause secondary pollution of the following stream.To tackle this problem, several methods combiningboth ponds and filtering system had been tried(Christian et al., 2003). Dongying multi-stageponds-wetlands ecosystem was designed embodyi… 相似文献
12.
Anne R. Fitzpatrick Valerie B. Link Wendy M. Yen George R. Burket Kyoko Ito Robert C. Sykes 《Journal of Educational Measurement》1996,33(3):291-314
In one study, parameters were estimated for constructed-response (CR) items in 8 tests from 4 operational testing programs using the l-parameter and 2- parameter partial credit (IPPC and 2PPC) models. Where multiple-choice (MC) items were present, these models were combined with the 1-parameter and 3-parameter logistic (IPL and 3PL) models, respectively. We found that item fit was better when the 2PPC model was used alone or with the 3PL model. Also, the slopes of the CR and MC items were found to differ substantially. In a second study, item parameter estimates produced using the IPL-IPPC and 3PL-2PPC model combinations were evaluated for fit to simulated data generated using true parameters known to fit one model combination or ttle other. The results suggested that the more flexible 3PL-2PPC model combination would produce better item fit than the IPL-1PPC combination. 相似文献
13.
以蚕豆为试材研究发现,在蚕豆离体幼苗(W W)衰老过程中,叶绿体色素和蛋白质含量均不断下降,而细胞膜透性逐渐升高.用质量浓度10mg/L的三唑酮浸种(T W)和浸种后在苗期喷施10mg/L的三唑酮(T T)处理可提高蚕豆幼苗叶片叶绿体色素和蛋白质的含量,并且两种处理尤其是T T处理方式均抑制蚕豆离体幼苗叶绿体色素和蛋白质含量的降低及细胞膜透性增加.表明三唑酮具有保护膜结构和延缓衰老的作用. 相似文献
14.
间歇低氧运动对大鼠血清总蛋白和白蛋白的影响 总被引：2，自引：0，他引：2
陈福刁 《韩山师范学院学报》2006,27(3):74-76
将40只SD雄性大鼠随机分为安静2组(常氧对照组和间歇低氧对照组)和运动2组 (常氧运动组和间歇低氧运动组),人工制造14．5％低氧(O2)环境,4周后对各组大鼠血清总蛋白(TP)和白蛋白(Alb)进行检测．检测结果显示:常氧运动组血清TP、Alb最高,与其他各组比较具有统计学意义(p<0．05);而间歇低氧运动组的血清TP、Alb虽然比常氧对照组低,但与间歇低氧对照组比较有上升趋势．结论:低氧环境下可使机体蛋白质代谢受阻, 但4周的间歇低氧运动可提高蛋白质代谢适应能力,有利于身体机能能力的提高． 相似文献
15.
苦参不同器官中的生物碱含量分析 总被引：2，自引：0，他引：2
[目的]探讨苦参不同器官中的生物碱含量,为该资源植物的合理应用提供依据.[方法]用薄层色谱法(TLC)分析测定了辽宁产苦参不同器官中苦参碱及氧化苦参碱含量.[结果]各类器官,除叶片外,氧化苦参碱含量均显著超过苦参碱含量;苦参碱含量以种子中的为最高,占干重的0.065%,其次为茎(0.034%)、根(0.016%)、叶(0.013%);氧化苦参碱含量以根最高,占干重的3.847%,其次为种子(1.982%)、茎(0.140%),叶中未检测到;粗老根(直径大于1 cm)与细嫩根(直径在0.5~1.0 cm)中的两种生物碱含量差别不大.[结论]达到一定生长年限后,生物碱积累不再有明显增加而趋于饱和;大部分器官中,氧化苦参碱含量高于苦参碱含量;种子及茎更适合作为苦参碱的提取器官. 相似文献
16.
He W Zhang FJ Wang SP Chen G Chen CC Yan M 《Journal of Zhejiang University. Science. B》2008,9(2):100-108
Background: Sevoflurane and propofol are effective cardioprotective anaesthetic agents, though the cardioprotection of propofol has not been shown in humans. Their roles and underlying mechanisms in anesthetic postconditioning are unclear.Mitochondrial permeability transition pore (MPTP) opening is a major cause of ischemia-reperfusion injury. Here we investigated sevoflurane- and propofol-induced postconditioning and their relationship with MPTP. Methods: Isolated perfused rat hearts were exposed to 40 min of ischemia followed by 1 h of reperfusion. During the first 15 min of reperfusion, hearts were treated with either control buffer (CTRL group) or buffer containing 20 μmol/L atractyloside (ATR group), 3% (v/v) sevoflurane (SPC group),50 μmol/L propofol (PPC group), or the combination of atractyloside with respective anesthetics (SPC ATR and PPC ATR groups). Infarct size was determined by dividing the total necrotic area of the left ventricle by the total left ventricular slice area (percent necrotic area). Results: Hearts treated with sevoflurane or propofol showed significantly better recovery of coronary flow,end-diastolic pressures, left ventricular developed pressure and derivatives compared with controls. Sevoflurane resulted in more protective alteration of hemodynamics at most time point of reperfusion than propofol. These improvements were paralleled with the reduction of lactate dehydrogenase release and the decrease of infarct size (SPC vs CTRL: (17.48±2.70)% vs (48.47±6.03)%,P＜0.05; PPC vs CTRL: (35.60±2.10)% vs (48.47±6.03)%, P＜0.05). SPC group had less infarct size than PPC group (SPC vs PPC:(17.48±2.70)% vs (35.60±2.10)%, P＜0.05). Atractyloside coadministration attenuated or completely blocked the cardioprotective effect of postconditioning of sevoflurane and propofol. Conclusion: Postconditioning of sevoflurane and propofol has cardioprotective effect against ischemia-reperfusion injury of heart, which is associated with inhibition of MPTP opening. Compared to propofol, sevoflurane provides superior protection of functional recovery and infarct size. 相似文献
17.
Nazim Hussain Hui Li Yu-xiao Jiang Zahra Jabeen Imran Haider Shamsi Essa Ali Li-xi Jiang 《Journal of Zhejiang University. Science. B》2014,15(2):181-193
Tocopherols (Tocs) are vital scavengers of reactive oxygen species (ROS) and important seed oil quality indicators. Nitrogen (N) is one of the most important fertilizers in promoting biomass and grain yield in crop production. However, the effect of different sources and application rates of N on seed Toc contents in oilseed rape is poorly understood. In this study, pot trials were conducted to evaluate the effect of two sources of N fertilizer (urea and ammonium nitrate). Each source was applied to five oilseed rape genotypes (Zheshuang 72, Jiu-Er-1358, Zheshuang 758, Shiralee, and Pakola) at three different application rates (0.41 g/pot (N1), 0.81 g/pot (N2), and 1.20 g/pot (N3)). Results indicated that urea increased α-, γ-, and total Toc (T-Toc) more than did ammonium nitrate. N3 was proven as the most efficient application rate, which yielded high contents of γ-Toc and T-Toc. Highly significant correlations were observed between Toc isomers, T-Toc, and α-/γ-Toc ratio. These results clearly demonstrate that N sources and application rates significantly affect seed Toc contents in oilseed rape. 相似文献
18.
番薯藤挥发性化学成分的分析 总被引：2，自引：0，他引：2
采用同时蒸馏萃取法对番薯藤幼苗和成熟番薯藤的挥发性成分进行了提取,用GC/MS方法对挥发性成分进行了鉴定,从幼番薯藤中鉴定了28种化学成分,从成熟的番薯藤中鉴定了26种成分,两者成分上有较大差异. 相似文献
19.
对福建省惠安县赤湖林场不同林龄木麻黄人工林细根能量现存量的季节动态进行了系统研究.结果表明：各林龄木麻黄人工林活细根和死细根中的灰分现存量和死细根中的能量现存量在3月和7月有两个峰值,而活细根中的能量现存量峰值则出现在秋冬季节和7月份;活细根中的灰分和能量现存量随林龄的增加先升高后下降,但峰值出现的时间不同,灰分出现在24林龄中,而能量则出现在30林龄中,死细根中的灰分和能量现存量随林龄的增加而升高.因此,木麻黄人工林细根能量的固定随着季节和林分林龄的变化而发生相应的变化. 相似文献
20.
Background： Electrochemical therapy （ECT） has been used to treat unresectable hepatic tumor. In order to improve its efficacy, we combined ECT with hyperthermia induced by electrothermal needle （ETN） （ETECT）. The aim of this study is to investigate the destructive effect of ETECT on normal rat liver. Methods： Twenty rats were randomized into 4 treatment groups （n=5 in each group）： control, ECT alone, hyperthermia alone and ETECT. Following the treatment, sections of the livers were histologically examined by light microscopy and the destructive volumes were measured with micrometer. Results： We found that the destructive volumes in ETECT group were the largest （P〈0.01）. In ETECT group coagulative necrosis was found in both anode and cathode areas, around which transition zones existed. The transition zones can only be seen when coulomb was increased in ECT group. Conclusion： ETECT was demonstrated to enhance the destructive effect of ECT. This study provides theoretical and experimental basis for a new local ablative treatment for unresectable primary liver tumor. 相似文献