大白菜组织结构感官品质与评定指标的关系

以１７个大白菜品种为试材，探讨组织结构与感官品质及营养成份的关系。结果表明，三者密切相关。质地受导管壁厚度及中肋细胞大小的影响。组织结构与产品贮藏营养物质、风味和质地密切相关。可用公式Ｙ＝２．１７２５６８－０．０３１６Ｘ１（短缩茎溶生腔％）＋５．００９３９Ｘ２（叶肉厚ｍｍ）对感官品质进行定量评价。     

基于感官模糊建模和糖酸分析评价‘红美人’杂柑的品质

为科学评价柑橘果实品质差异，以9份‘红美人’（‘爱媛28’）杂柑为研究材料，对其常规品质指标、可溶性糖和有机酸含量进行检测，同时组织评价人员对样品各感官属性喜好度及属性权重等级进行评价。关联6个感官属性的感官评价结果与相关风味物质代谢数据，结果表明：‘红美人’汁胞中的可溶性糖主要是果糖、葡萄糖和蔗糖，其中样品3和8可溶性糖含量较高，样品1和9较低；汁胞中的有机酸主要是柠檬酸，还有少量的苹果酸，其中样品5、3和1总酸含量较高，样品9最低；评价人员对各品质属性的关注度依次为果肉甜度>果肉酸度>果肉化渣性>果实香气>果实色泽=果实外形，且感官综合评价得分最高的是样品9、3和2；感官综合得分与果肉甜度、果肉化渣性和果实香气具有显著相关性；糖度感官评价与果糖、葡萄糖、总糖和可溶性固形物呈显著正相关，与苹果酸显著负相关。     

黄瓜质地与组织结构、纤维素及果胶含量的关系

通过对不同质地品质黄瓜品种的石蜡切片观察及纤维素和果胶含量分析,发现果皮比较薄,由表皮向内薄壁细胞体积增加快,果肉细胞形状规则,圆形、近圆形细胞多的品种,质地品质好。纤维素含量高,果胶含量低的果实不脆,含量适中的果实脆嫩,品质好。黄瓜肉质脆性与组织结构、纤维素、果胶含量关系密切。     

福鼎槟榔芋特征特性与高产栽培技术要点

福鼎槟榔芋特征特性与高产栽培技术要点马静，张一言（福建省福鼎县农科所３５５２００）（福鼎县农技站）福鼎槟榔芋又名山前芋、福鼎芋，属天南星科芋属的一个栽培种。它以个体大，品质优，质地松酥，香气浓厚，风味独特，富含淀粉、蛋白质及各种氨基酸而享誉国内外，于...     

西瓜品质构成分析

利用43份材料,对构成西瓜品质的性状进行全面分析,研究了西瓜感官品质与理化性状之间的关系以及各性状间的相互关系。相关分析结果表明,感官鉴定是评价西瓜品质的重要因素,甜度、风味、质地、多汁度和剖面颜色5项评价与综合评价均表现为极显著的正相关关系,糖、有机酸与感官鉴定各项目均表现为正相关,果胶、纤维、含水量与感官鉴定各项均表现为负相关。通径分析和主成分分析结果显示,在检测的20项理化性状中,可溶性固形物含量、各种糖含量、含水量、纤维含量等性状是决定西瓜品质的主要性状。     

柑橘鲜果检验方法进展

果实品质是决定果品市场竞争力的主要因素，但影响果实品质的因素很多，包括感官品质、风味品质和营养品质等，各因素之间存在密切相关性或相对独立性。在实际果品分析试验过程中，参考文献中有关分析试验方法很多，由于采用不同方法获的结果有一定的差异性，故果实品质指标参数的采集需要标明采用的试验方法及相关设备，只有这样方可作出比较正确的评价结果。     

基于质地多面分析法对平菇质构特性的分析

以平菇108-2、108-3及108-9 3个供试菌株为试材,采用感官评价和质构仪质地多面(TPA)分析法,研究发酵料及发酵熟料2种栽培模式对平菇子实体不同部位质地参数的影响,以期为平菇子实体质构分析和平菇育种提供参考依据。结果表明：不同模式下子实体质地特性差异主要是由品种决定;TPA质地参数可以代替感官品质评价,菌柄的质地参数大多高于菌盖;利用多元统计分析(主成分分析和相关性分析)能够提取到4个主成分,累计方差贡献率达到79.54%,其中硬度、咀嚼性及内聚性3个参数可用来反映平菇子实体质地特性。     

不同生态区富士苹果果皮解剖结构的特征与差异

通过对我国不同生态区富士苹果果实品质的调查和解剖结构观察，发现不同生态区富士果皮角质膜厚度、质地均一程度和外表光洁度各异；果皮角质膜质地均一是果面光洁的重要特征；表皮细胞的大小、形状和排列方式等影响角质膜厚度和质地均一性；不同地区果皮机械组织厚度、细胞层数、细胞大小和排列方式各异。在相对湿度低、降雨量少的地区，表皮细胞稀疏，机械组织发达。     

薄皮甜瓜组织结构、纤维素及果胶含量与果实感官品质的关系

以玉美人、龙甜3号、高甜黄金道、日本甜宝和香沙蜜5个薄皮甜瓜品种为试材,鉴定了成熟期各品种感官品质,观察了石蜡切片,并测定了果实中纤维素和可溶性果胶含量。结果表明:薄皮甜瓜表皮细胞切面小,表面积大,薄壁细胞递增快,近圆形细胞较多,且大小均匀,则果实感官品质好。同时,成熟果实中纤维素含量在0.24%～0.28%之间,可溶性果胶含量低,利于感官品质的提高。薄皮甜瓜感官品质与成熟果实中组织结构、纤维素和果胶含量关系密切。     

袋栽平菇输液式补水试验研究

以袋栽平菇为试验材料，研究输液式补水方法对平菇产量、单丛重量和感官品质的影响，结果表明：（1）袋栽平菇通过输液式补水处理后总产量增加。补水处理从4潮菇开始产量明显增加，其中以第1潮菇采收后补水10min／d的增产效果最好，达到18．5％。（2）输液式补水处理后，从第4潮菇开始可明显提高单丛菇重，但各处理间单丛菇重的差异不明显。在平菇的采收后期，通过输液式补水所产出菇的感官品质明显较对照（不补水）好。（3）每天对平菇茵袋直接输入10mL的水分即能提高平菇的产量和品质。     

Effects of radiation from 188Re on smooth muscle cell proliferation

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.     

Relationship between renal hypertension and cardiac α1-adrenoceptor autoantibodies in rats

AIM: To examine the autoantibody against α₁-adrenoceptor and its biologic activities during the development of renal hypertension. METHODS: Renal hypertension of rat was achieved by clipped renal artery, the titre of autoantibody to α₁-adrenoceptor was detected using ELISA immunoassay. Furthermore, the biological offects of these autoantibodies on cultured cardiomyocytes were also examined. RESULTS: After two weeks of clipping renal arteries, both the frequency of occurrence and the titre of autoantibodies to cardiac α₁-adrenergic receptor were significantly increased as compared with the control of pre-treatment. The increased autoantibodies lasted for several weeks and then automatically decreased gradually to the pre-clipping level at 12 weeks. The biological effects of these autoantibodies displayed an "agonistic-like" activities on the beating frequency of cultured neonatal cardiomyocytes. CONCLUSION: Autoantibodies against α₁-adrenoceptor may play a role in the elevation of peripheral vascular resistance and in the development of cardiac hypertrophy in rats with renal hypertension.     

Influence of Mineral Nutrients on Strawberry Fruit Quality and Their Accumulation in Plant Organs

Abstract

This review is based partly on complete articles and partly on abstracts. Three of the 60 articles deal with the total uptake of elements in strawberry plant organs in two different strawberry production systems, both considered as optimal concerning amount and balance of elements. The effect on fruit quality may be dramatic if the level of a particular element is outside this range, but there may also be effects initiated by differences within the optimal range of elements. Most articles refer to product oriented quality, but some focus on consumer oriented quality, as discussed by Shewfelt (1999). The discussion here is on a general basis, so one should keep in mind that there are cultivar differences and that specification of nutrition ideally should mirror the needs of a single cultivar, or a group of cultivars with similar requirements. Also, to get a complete understanding of the subject future reviews should embrace a broader access of information including the effect on plant development of individual elements, such as the role of calcium in fruit firmness and its importance in cell wall structure. However, the intention here is to narrow the information to results that suggest a direct connection between nutrient uptake and fruit quality.     

多效唑对猕猴桃离体试管苗生长及内源激素的影响

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。     

Proteomic analysis between pathological scars and normal skin

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.     

Mixed-severity fire regime in a high-elevation forest of Grand Canyon,Arizona, USA

Fire regime characteristics of high-elevation forests on the North Rim of the Grand Canyon, Arizona, were reconstructed from fire scar analysis, remote sensing, tree age, and forest structure measurements, a first attempt at detailed reconstruction of the transition from surface to stand-replacing fire patterns in the Southwest. Tree densities and fire-/non-fire-initiated groups were highly mixed over the landscape, so distinct fire-created stands could not be delineated from satellite imagery or the oldest available aerial photos. Surface fires were common from 1700 to 1879 in the 4,400 ha site, especially on S and W aspects. Fire dates frequently coincided with fire dates measured at study sites at lower elevation, suggesting that pre-1880 fire sizes may have been very large. Large fires, those scarring 25% or more of the sample trees, were relatively infrequent, averaging 31 years between burns. Four of the five major regional fire years occurred in the 1700s, followed by a 94-year gap until 1879. Fires typically occurred in significantly dry years (Palmer Drought Stress Index), with severe drought in major regional fire years. Currently the forest is predominantly spruce-fir, mixed conifer, and aspen. In contrast, dendroecological reconstruction of past forest structure showed that the forest in 1880 was very open, corresponding closely with historical (1910) accounts of severe fires leaving partially denuded landscapes. Age structure and species composition were used to classify sampling points into fire-initiated and non-fire-initiated groups. Tree groups on nearly 60% of the plots were fire-initiated; the oldest such groups appeared to have originated after severe fires in 1782 or 1785. In 1880, all fire-initiated groups were less than 100 years old and nearly 25% of the groups were less than 20 years old. Non-fire-initiated groups were significantly older (oldest 262 years in 1880), dominated by ponderosa pine, Douglas-fir, or white fir, and occurred preferentially on S and W slopes. The mixed-severity fire regime, transitioning from lower-elevation surface fires to mixed surface and stand-replacing fire at higher elevations, appeared not to have been stable over the temporal and spatial scales of this study. Information about historical fire regime and forest structure is valuable for managers but the information is probably less specific and stable for high-elevation forests than for low-elevation ponderosa pine forests.This revised version was published online in May 2005 with corrections to the Cover Date.     

Coupling past management practice and historic landscape change on John F. Kennedy Space Center,Florida

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.     

瓜叶绿素降解关键酶基因PPH和PAO cDNA片段的克隆与表达初步分析

 以西双版纳黄瓜和‘华黄5号’黄瓜叶片为试验材料,研究了衰老过程中两种黄瓜叶片叶绿素含量变化及脱镁叶绿素脱镁叶绿酸水解酶基因PPH和脱镁叶绿酸a加氧酶基因PAO的表达。结果表明：随着叶片衰老,叶绿素a和叶绿素b含量显著降低,叶绿素a与叶绿素b的比值在0.5左右,推测叶绿素b的含量可能对黄瓜叶片保绿起到重要作用。荧光定量RT-PCR分析结果显示：PPH和PAO在西双版纳黄瓜叶片生长35 d时表达量最高,分别为5.50和1.86;PPH在‘华黄5号’叶片35 d时表达量最高,为7.14,而PAO在35和45 d表达量都很高,分别为3.90和3.91;PPH和PAO在西双版纳黄瓜叶片中的表达量低于在‘华黄5号’中。     

Effects of simvastatin on PDGF-BB and serum-induced proliferation of vascular smooth muscle cells and on the expression of tumor suppressor gene PTEN

AIM:To observe the effect of simvastatin on the proliferation of vascular smooth muscle cells(VSMCs) induced by serum and growth factor PDGF-BB and the effect of simvastatin on the expression of PTEN,a important regulator of G₁/S cell cycle transition. METHODS:The DNA synthesis was determined by [³H]-TdR incorporation, cell cycle was examined with flow cytometry, the protein level of PTEN was measured by Western blot method. RESULTS: (1)Simvastatin inhibited [³H]-TdR incorporation in a dose dependent manner. (2) Flow cytometric DNA analysis revealed that simvastatin induced significantly enhancement of G₀/G₁ phase and decrease in S phase VSMCs.(3)Simvastatin increased protein level of PTEN and mevalonate, a metabolite of HMG-COA, reversed the effect of simvastatin on PTEN protein expression. CONCLUSION:Simvastatin may inhibit proliferation of VSMCs and retarded cell cycle in G₀/G₁ phase by increasing PTEN expression through inhibiting synthesis of mevalonate.     

XBP-01 accelerated apoptosis induced by oxidized low density lipoprotein in vascular smooth muscle cells

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.