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以“白玉堂”“寒地月季”“粉团蔷薇”“十姊妹”和“狗蔷薇” 5种月季砧木为试材，采用人工低温胁迫处理的方法，研究了4、-3℃和-10℃3个温度处理对5种月季砧木枝条生长、抗氧化酶活性、细胞膜功能和渗透调节物质含量的影响，以期为月季砧木的利用提供参考依据。结果表明：随着温度的降低，各月季砧木枝条的发芽率和生根率降低，根的伸长生长受到抑制，过氧化物酶、过氧化氢酶和超氧化物歧化酶活性增强，相对电导率、丙二醛含量、脯氨酸含量、可溶性糖和可溶性蛋白质含量增加。其中，“寒地月季”通过显著提高抗氧化酶活性和渗透调节物质含量、维持细胞膜正常功能等途径来适应低温胁迫，表现出较强的抗寒性，其次是“粉团蔷薇”和“白玉堂”,而“十姊妹”和“狗蔷薇”的抗寒性最差。 相似文献
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以弯刺蔷薇(Rosa beggeriana)和大花白木香(R.fortuneana)当年生叶片和枝条为试材,采用电解质渗出率拟合Logistic方程确定低温半致死温度(LT_(50))评价抗寒性,采用过碘酸雪夫氏染色观察茎中淀粉积累,测定相对含水量、丙二醛、可溶性糖、脯氨酸、脱落酸含量以及超氧化物歧化酶、过氧化物酶和过氧化氢酶活性,研究其越冬期间抗寒性变化及其生理基础。结果发现:两种蔷薇叶片抗寒能力相当,但弯刺蔷薇枝条抗寒性远强于大花白木香。与大花白木香相比,弯刺蔷薇在低温驯化初期累积了更多的可溶性糖,并在叶片脱落前可能通过增加的ABA信号促进可溶性糖由叶片向茎中运输并贮存为淀粉,在严冬时期淀粉水解形成更多的渗透调节物质,并通过更高的SOD活性维持氧化还原平衡;而大花白木香中只发现了比弯刺蔷薇中更高的脯氨酸含量和POD活性,这可能难以维持其渗透压和氧化还原平衡并造成了更多的膜脂过氧化伤害,最终导致其枝条的抗寒性远小于弯刺蔷薇。 相似文献
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《河北果树》2015,(5)
2013年进行了低温胁迫对葡萄砧木枝条抗寒性的影响试验。以8种葡萄砧木为试材,采用组织褐变法和恢复生长法,测定葡萄砧木在低温(-2、-15、-20、-25、-30、-35℃)胁迫下枝条韧皮部和木质部的褐变率、扦插愈伤、萌芽和生根率进行了观测。结果表明:各砧木品种的枝条韧皮部和木质部褐变程度均随温度的降低而逐渐加重,枝条不同组织的抗寒力差异明显,即木质部韧皮部。各低温胁迫下贝达枝条韧皮部和木质部褐变率最低,101和5BB韧皮部和木质部褐变率高;贝达、110R和188等萌芽及生根率始终处于较高水平,3309C始终处于较低水平。各砧木品种枯死率除3309C在-30℃,188在-25℃全部枯死,贝达、101、5BB和5C均在-35℃枯死率达100%。综合评价得出,贝达砧木抗寒性最强,3309C、110R、SO4、5C抗寒性较强,188、101和5BB抗寒性较弱;各品种能抵御的临界最低温度为-20℃。 相似文献
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引种条件下八种新疆野生蔷薇种子自然萌发规律 总被引：1，自引：0，他引：1
以引种条件下8种新疆野生蔷薇种子为试材,采用低温层积处理和打磨种子的方法,研究了种皮厚度和低温层积处理对新疆野生蔷薇种子的影响。结果表明:种皮厚度为0.408~0.665mm,发芽率均超过50%的由高到低依次是弯刺蔷薇、疏花蔷薇、伊犁蔷薇和宽刺蔷薇,发芽率分别为87.17%、72.17%、75.44%和68.97%,与这4种蔷薇种子种皮打磨处理相比,无明显差异。而蔷薇种子种皮厚度0.665mm,正常种皮厚度下,尖刺蔷薇、刺蔷薇、大果蔷薇和大花密刺蔷薇发芽率均较低,其中大花密刺蔷薇的发芽率为0.00%,与种皮打磨处理相比,都不同程度地提高了这4种蔷薇种子的发芽率。弯刺蔷薇、伊犁蔷薇、疏花蔷薇和宽刺蔷薇种子发芽高峰基本集中于将种子进行低温层积处理后7~9d。 相似文献
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果梅种质枝条抗寒性鉴定 总被引：24，自引：1，他引：24
通过电导法对28份果梅种质的枝条抗寒性进行了比较分析,同时研究了枝条的可溶性蛋白、可溶性糖和丙二醛(MDA)的含量与果梅种质抗寒性的关系。结果表明:果梅种质资源的枝条抗寒性存在着很大的差异,经12h低温处理,其枝条的半致死温度为-9.3℃--20.2℃,其中丰后、高田丰后、软条红梅等种质比较抗寒,半致死温度分别为-20.2℃、-17.7℃、-19.3℃;东青、开蒂和红顶等种质抗寒性较差,半致死温度分别为-9.4℃、-9.4℃、-9.3℃;果梅枝条中可溶性蛋白和糖类与种质的抗寒性呈正相关关系,相关系数分别为0.93959和0.86709,而与丙二醛含量呈负相关关系,相关系数为-0.952122。 相似文献
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AIM: Although endovascular radiotherapy inhibits neointimal hyperplasia, the exact alterations induced by β-particles irradiation remain to be elucidated. The objective of this study was to investigate the ability and the cellular mechanism of local β-particles emission from 188Re to inhibit vascular smooth muscle cells (SMCs). METHODS: The SMCs in vitro were irradiated by 188Re with single doses of 2.6 Gy-25.8 Gy. The effects of β-particles on SMCs, such as effective irradiate doses, the period of inhibition for SMCs proliferation, the changes of cell proliferation rate and DNA synthesis rate, cell cycle progression and related gene expression, were investigated by cell count, [3H]-TdR incorporation, cell cycle progression analysis, cell viability and immunocytochemistry, respectivecy. RESULTS: β-particles irradiation with dose of 5.2 Gy could inhibit significantly SMCs proliferation. At dose of 20.6 Gy DNA synthesis inhibitory rate was 92%, SMCs proliferation rate was only 3%. Renoval of 188Re did not abolish the inhibitory effects of β-particles on SMCs proliferation. The expression of P53 was up regulation and PCNA was down regulation after irradiation. CONCLUSION: β-particles from 188 Re was significantly effective and permanent in inhibiting SMCs proliferation, and inhibitory effect was in dose-dependet manner ED50was 5 Gy, the best dose to inhibit SMCs proliferation was 20 Gy. β-particles irradiation induced SMCs to occur G0/G1 arrest, damaged the ability of SMCs reproliferation and led to cell clonogenic death. P53 and PCNA had regulatiory effects on SMCs proliferation after β-particles irradiation. 相似文献
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AIM:To study the effect of L-Arg on plasma content of endothelin (ET) and the expression of proto-oncogene c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy. METHODS: The level of c-fos mRNA were measured by in situ hybridization. The ET in plasma were measured by radioimmunoassay. RESULTS:After eight weeks of treatment with L-Arg, the expression of c-fos decreased markedly (P＜0.01). The ET content in plasma also decreased significantly by L-Arg(P＜0.01).CONCLUSION: Plasma ET content and the expression of c-fos in the left ventricle of rats with renovascular hypertensive hypertrophy could be decreased by L-Arg administration. 相似文献
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《International Journal of Fruit Science》2013,13(3):101-120
Abstract Saskatoon berry (Amelanchier alnifolia Nutt., Rosaceae) and blueberry (Vaccinium corymbosum L., Ericaceae) are substantially equivalent in all characteristics that are important to the consumer, including fruit color, shape, size, nutrition, texture, and uses. In addition, both fruits are native to North America and they have practically identical historical uses and known health benefits. Their composition, processing, nutritional value and metabolism, intended uses, and levels of undesirable substances are compared. 相似文献
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多效唑对猕猴桃离体试管苗生长及内源激素的影响 总被引：18，自引：0，他引：18
多效唑（ＰＰ３３３）处理猕猴桃试管苗，降低了其生长强度；植株体内的ＧＡ３、ＩＡＡ和ＺＴ含量下降，ＡＢＡ的含量上升，乙烯释放率增加；并且能降低外源的ＧＡ３和ＩＡＡ促进生长的作用，而外源的ＧＡ３和ＩＡＡ又能不同程度地逆转多效唑的抑制作用，使植株恢复生长。 相似文献
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HU Zhi-cheng ZHU Jia-yuan ZHU Bin GUO Dong CHEN Bin ZHANG Kai HU Kun-hua LI Ming-tao TANG Bing 《园艺学报》2011,27(9):1802-1806
AIM: To investigate and screen the sensitive proteins in the formation mechanism of pathological scars by comparing the results of differential proteomic analysis between pathological scars and normal skin.METHODS: Two-dimensional gel electrophoresis was used to detect the protein expression profiles in 8 keloid patients, 8 hypertrophic scar patients and 3 matched normal skin patients.The proteins that showed differential expression of over 4-fold change were cut and analyzed by MALDI-TOF/TOF mass spectrometry.RESULTS: A two-dimensional protein profiling comparison between pathological scars and normal skin was successfully established.On average, 2 978 spots in keloid, 2 975 spots in hypertrophic scar and 3 053 spots in normal skin were identified using gel analysis software.Compared with normal skin, there were totally 36 differentially-expressed proteins in keloid and hypertrophic scar identified from the spots of over 4-fold change, including 16 proteins in both keloid and hypertrophic scar (8 up-regulated and 8 down-regulated), 11 only in keloid (9 up-regulated and 2 down-regulated) and 9 only in hypertrophic scar (4 up-regulated and 5 down-regulated).CONCLUSION: Proteomic analysis can identify the proteins with variance of pathological scars versus normal skin, thus providing probable new clues to reveal the formation mechanism of pathological scars. 相似文献
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The objective of this study was to establish a cryopreservation protocol for hawthorn shoot apices (Crataegus pinnatifida Bge.). Cryopreservation was carried out via encapsulation–dehydration, vitrification, and encapsulation–vitrification on shoot apices excised from in vitro cultures. We began by showing that cold-acclimation enhanced the regrowth of cryopreserved apices from 10.0 to 65.5% in encapsulation–dehydration. We then decided that the encapsulation–dehydration method was an optimal cryopreservation method for hawthorn shoot apices in terms of its high recovery after cryopreservation as well as its ease of use compared with vitrification and encapsulation–vitrification. In encapsulation–dehydration, the protocol leading to optimal regrowth was as follows: after cold-acclimation at 5 °C in the dark for 2 weeks, excised shoot tips were pretreated for 24 h at 25 °C on hormone-free Murashige and Skoog [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiol. Plant. 15, 473–497] (MS) basal medium with 0.4 mol/L sucrose, then encapsulated and precultured in liquid MS medium with 0.8 mol/L sucrose for 16 h at 25 °C. Precultured beads were dehydrated for 6 h at 25 °C in the dessicator containing 50 g silica gel to a moisture content of 15.3% (fresh-weight basis) before cryostorage for 1 h. In addition, we examined the effect of adding glycerol to both the alginate beads and loading solution to enhance regrowth after cryopreservation in encapsulation–dehydration. In the present study, it was shown that adding 0.5 mol/L glycerol resulted in high regrowth percentages (82.5–90.0%) in four Crataegus species. 相似文献
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AIM:To investigate the effect of metallothionein(MT) on proliferation of rat vascular smooth muscle cells (VSMCs) stimulated by homocysteine and its mechanism. METHODS:VSMCs proliferation was measured by [3-H]-TdR incorporation, mitogen-activated protein kinase(MAPK)activity were determined by immunoprecipitation method, the intracellular contents of MT and malondialdehyde (MDA)were assayed by -hemoglobin saturation method and TBA reaction, respectively, and lactate dehydrogenase (LDH) leakage was measured by NADH oxidation. RESULTS:Hcy(10-6-10-4 mmol/L) stimulated [3-H]-TdR incorporation by the VSMCs in a concentration-dependent manner. Compared with control, [3-H]-TdR incorporation in VSMCs treated with 0.1 mmol/L Hcy was increased by 4.2 fold (P＜0.01). Meanwhile, Hcy enhanced MAPK activity, MDA formation and LDH release (P＜0.01)in a concentration-dependent manner. Treatment of VSMCs with MT alone did not change above parameters, compared with control. However, MT (10-6-10-4 mol/L)attenuated significantly Hcy-stimulated proliferation of VSMCs (P＜0.01)in a concentration-dependent manner. And MT inhibited obviously Hcy-induced activation of MAPK activity, MDA formation and LDH release. Preincubation of VSMCs with 0.5 mmol/L ZnCl2 for 6 h induced an increase cellular MT content by 5.7-fold (P＜0.01). The MT-overexpressed VSMCs resisted Hcy-stimulating action on MAPK activity, MDA formation and LDH leakage (P＜0.01). CONCLUSION:These results show that MT has an inhibitory effect on Hcy-induced VSMCs proliferation, and that MT could inhibit Hcy-stimulated MAPK activity and lipid peroxidation. 相似文献
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Duncan Brean W. Boyle Shannon Breininger David R. Schmalzer Paul A. 《Landscape Ecology》1999,14(3):291-309
Historic landcover dynamics in a scrubby flatwoods (Tel-4) and scrub landscape (Happy Creek) on John F. Kennedy Space Center were measured using aerial images from 1943, 1951, 1958, 1969, 1979, and 1989. Landcover categories were mapped, digitized, geometrically registered, and overlaid in ARC/INFO. Both study sites have been influenced by various land use histories, including periods of range management, fire suppression, and fire management. Several analyses were performed to help understand the effects of past land management on the amount and spatial distribution of landcover within the study sites. A chi-squared analysis showed a significant difference between the frequency of landcover occurrence and management period. Markov chain models were used to project observed changes over a 100-year period; these showed current management practices being effective at Tel-4 (restoring historic landscape structure) and much less effective at Happy Creek. Documenting impacts of past management regimes on landcover has provided important insight into current landscape composition and will provide the basis for improving land management on Kennedy Space Center and elsewhere. 相似文献
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AIM: Previous studies performed with XBP-01 in vitro indicated that XBP-01 could inhibit vascular smooth muscle cells from being transformed into foam cell and could eliminate the atherosclerotic plaque in C57BL/6J mouse. This experiment is to investigate its mechanism of eliminating plaques in vitro. METHODS: The cultured porcine artery smooth muscle cells incubated with XBP-01 of 0.1 mg/L for 24 h after preincubated with oxidized low density lipoprotein of 15 mg/L for 72 h in vitro. The samples were analyzed by fluorescence microscope, confocal microscope system and flow cytometry. RESULTS: Apoptosis was triggered by being incubated with oxidized low density lipoprotein and this process was accelerated additionally by being incubated with XBP-01. CONCLUSION: XBP-01 can be effective in eliminating atherosclerotic plaque by accelerating the process in which oxidized low density lipoprotein induced smooth muscle cell apoptosis. 相似文献
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Species distribution models (SDMs) often use elevation as a surrogate for temperature or utilise elevation sensitive interpolations
from weather stations. These methods may be unsuitable at the landscape scale, especially where there are sparse weather stations,
dramatic variations in exposure or low elevational ranges. The goal of this study was to determine whether radiation, moisture
or a novel estimate of exposure could improve temperature estimates and SDMs for vegetation on the Illawarra Escarpment, near
Sydney, Australia. Forty temperature sensors were placed on the soil surface of an approximately 12,000 ha study site between
November 2004 and August 2006. Linear regression was used to determine the relationship with environmental factors. Elevation
was correlated more with moderate temperatures (winter maximums, summer minimums, spring and autumn averages) than extreme
temperatures (summer maximums, winter minimums). The correlation (r
2) between temperature and environmental factors was improved by up to 0.38 by incorporating exposure, moisture and radiation
in the regressions. Summer maximums and winter minimums were predominately determined by exposure to the NW and coastal influences
respectively, while exposure to the NE and SW was important during other seasons. These directions correspond with the winds
that are most influential in the study area. The improved temperature estimates were used in Generalised Additive Models for
37 plant species. The deviance explained by most models was increased relative to elevation, especially for moist rainforest
species. It was concluded that improving the accuracy of seasonal temperature estimates could improve our ability to explain
the patchy distribution of many species.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献