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1.
液态CO_2对香菇速冻的工艺研究   总被引:1,自引:0,他引:1  
采用喷雾式流态化液态CO2速冻和缓冻,探讨了在选用不同的筛板、风速和食品层高,以及不同的冻结温度下香菇的流化状态,冻结速率与解冻后冻品汁液流失率之间的关系等。结果表明,选用开孔率为50%,孔径为5mm的筛板,采用3.0m·s-1~3.5m·s-1循环风速对床层高度为6cm的新鲜香菇进行流态化速冻效果最佳。建议采用-60℃以下温度进行冻结,冻品在-26℃冰箱中贮藏6个月后,解冻时的汁液流失率低于3.3%。  相似文献   

2.
采用液氮速冻 ,探讨在不同冻结条件下鸡油菌的冻结温度曲线及冻结温度与解冻后鸡油菌的汁液流失率之间的关系。结果表明 :在 - 6 0℃对鸡油菌进行冻结时 ,出现了明显的冻结三阶段现象 ,而在其它温度下冻结时此三阶段不明显 ;建议采用 - 80℃以下温度进行冻结 ,冻品在 - 2 6℃冰箱中冻藏 6个月 ,解冻后的汁液流失率低于 2 7%。  相似文献   

3.
采用喷雾式流态化液氮速冻及缓冻,研究了在不同的冻结工艺条件下白灵菇的冻结温度曲线及冻结速度与汁液流失率之间的关系等。结果表明:对白灵菇进行缓慢冻结时,有明显的冻结三阶段现象出现,而在液氮速冻时此三阶段不明显;建议采用-60℃以下温度进行冻结,冻品在-26℃冰箱中贮藏9个月后,解冻时的汁液流失率低于4.9%。  相似文献   

4.
研究了在不同的烫漂温度和烫漂时间下青头菌过氧化物酶(Peroxidase,POD)活性的变化.烫漂及冻藏对青头菌过氧化物酶活性、氨基酸、矿质元素、维生素及氨基酸态氨等成分的影响结果表明:采用95~96℃烫漂温度效果最好,在4min内过氧化物酶活性降低了95.5%;烫漂及冻藏都使青头菌营养成分受到不同程度的损失建议采用一70℃以下温度不经烫漂而冻结,冻品在-26℃冰箱中贮藏12个月,其营养价值保持很好。  相似文献   

5.
采用喷雾式流态化液态CO2速冻及缓冻技术,研究了冻结温度、速度对双孢蘑菇多酚氧化酶(PPO)和过氧化物酶(POD)活性的影响。结果表明:冻结温度、速度对酶的活性有明显的影响,在75℃、60℃、45℃及35℃(缓冻)下进行冻结时,双孢蘑菇的PPO活性分别下降了70.5%、66.3%、56.8%及19.6%,POD活性分别下降了74.3%、71.1%、64.5%及21.6%。  相似文献   

6.
冻结速率对松茸PPO和POD活性的影响   总被引:6,自引:0,他引:6  
采用喷雾式流态化液氮速冻及缓冻.研究了冻结速率对松茸多酚氧化酶(PVO)及过氧化物酶(POD)活性的影响。结果表明:冻结速率对醇的活性有明显的影响,在-80℃、-60℃及-35℃(缓冻)下进行冻结,松茸的PPO活性分别下降了72.5%、67.7%及24.6%.POD活性分别下降了62.8%、53.5%及17.6%。  相似文献   

7.
采用喷雾式流态化液氮速冻及缓冻,研究了冻结温度、速度对黑牛肝菌多酚氧化酶(PPO)及过氧化物酶(POD)活性的影响。结果表明:冻结温度、速度对酶的活性有明显的影响,在-100℃、-80℃、-60℃及-35℃(缓冻)下进行冻结,黑牛肝菌的PPO活性分别下降了73.5%、70.6%、65.2%及18.0%,POD活性分别下降了68.4%、62.2%、51.7%及15,8%。  相似文献   

8.
不同荔枝品种果肉冻藏特性研究   总被引:1,自引:0,他引:1  
开展了水东、妃子笑、桂味、糯米糍、水晶球、怀枝等不同荔枝品种果肉的速冻冻藏特性研究,结果表明,水东、妃子笑、桂味、糯米糍是比较适合加工速冻荔枝的品种;而怀枝由于果肉较细软,取肉难度较大,而且解冻后汁液容易流失,不适宜加工速冻荔枝果肉;-60℃冻藏条件有利于速冻荔枝果肉的长期保存。  相似文献   

9.
冻结条件对黑牛肝菌营养价值影响的研究   总被引:1,自引:0,他引:1  
研究了在不同的烫漂温度及时间下黑牛肝菌过氧化物酶(Peroxidase.POD)活性的变化,烫漂及冻藏时黑牛肝菌过氧化物酶活性、氨基酸、矿质元素、维生素及氨基酸态氮等成分的影响。结果表明:采用95-96℃烫漂温度效果最好。在3min内过氧化物酶活性降低了95.5%,烫漂及冻藏都使黑牛肝菌营养成分受到不同程度的损失。建议采用-80℃以下温度不经烫漂漂而冻结.冻品在-26℃冰箱中贮藏12个月.其营养价值保持很好。  相似文献   

10.
以香蕉和青头菌为原料酿制风味香蕉果酒,研究了青头菌汁液对香蕉汁酒精发酵的影响.实验结果表明,青头菌汁液对香蕉果酒发酵具有促进作用,最适条件为发酵温度30℃,果酒干酵母用量0.10%,果汁外观糖度18%,青头菌汁液4%,发酵7d,酒精产率达8.4% vol.  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
AIM: To detect the expression of cytoplasmic inhibitor of apoptosis protein 2 (c-IAP2) and growth arrest-specific gene 1 (GAS1) in Hodgkin's lymphoma (HL) and anaplastic large cell lymphoma (ALCL) and to investigate the role of two genes in the pathogenesis of HL and ALCL.METHODS: HE staining, the antibodies CD30, CD15, CD45RO and CD20 were used to screen the cases of HL and ALCL from 288 cases of lymphoma. The clarified HL and ALCL were subjected for immunohistochemical staining by SP and ABC methods to analyze the expression of c-IAP2 and GAS1. RESULTS: ①The positive rate of c-IAP2 in HL was 25/26(96.1%) while that in ALCL was 6/19(31.6%), there presented statistic significance between HL and ALCL groups(P<0.05), meanwhile the positive rate of GAS1 showed statistic significance between HL and ALCL groups(P<0.05). ②Two cases were showed to be a mixed type combined with large tumor cells of HL and relatively smaller tumor cells of ALCL.CONCLUSION: ①The different expression of c-IAP2 and GAS1 in HL and ALCL implied a different mechanism of oncogenesis and the different defects in the pathway of signal transduction of apoptosis in HL and ALCL;②Few cases showed an overlap and a likely transitional state between HL and ALCL; ③The different expressing manner of GAS1 and c-IAP2 in HL and ALCL implied the potential marks for the differential dignosis of two kinds of lymphoma.  相似文献   

18.
Zusammenfassung Die Leistungsprüfungen wurden im Zeitraum 1997 bis 2003 mit den Unterlagen Gisela 4 und 5, den Klonnummern 195/20 und 497/8 aus der Gisela-Serie sowie Weiroot 10, 13, 53, 72 und 158 durchgeführt. Dabei dienten Sämlinge von P1 (bulgarische Selektion aus Prunus mahaleb) als Kontrolle. Alle Unterlagen waren mit der Sorte Stella veredelt und im Dezember 1996 in der Versuchsanlage der Agraruniversität in Plovdiv, Bulgarien, im Abstand von 6 m×4,5 m gepflanzt worden. Dabei erfolgte ein Pflanzschnitt. Nach Abschluss der natürlichen Kronenentwicklung wurde jedes Jahr ein Winterschnitt vorgenommen. Der Boden wurde durch mechanische Bearbeitung offen gehalten und nach dem 4. Standjahr wurden die Baumstreifen mit Herbiziden behandelt. Die Wasserversorgung erfolgte durch eine dem natürlichen Gefälle folgende Überflutung, allerdings nicht immer zum optimalen Zeitpunkt, da keine eigene Wasserquelle zur Verfügung stand.Basierend auf den Ergebnissen bis zum Anfang des 7. Standjahres können die untersuchten Unterlagen in zwei Gruppen differenziert werden: starkwüchsig—Weiroot 10, P1 und Weiroot 13; mittelstarkwachsend bis schwachwüchsig—Gi 497/8, Gisela 4, Weiroot 53, Weiroot 158, Gi 195/20, Weiroot 72 und Gisela 5. Letztere zeichnete sich durch besondere Schwachwüchsigkeit aus. Die meisten Wurzelschosser bildeten Gisela 4, Weiroot 10 und Weiroot 13. Weiroot 53, Weiroot 72 und Weiroot 158 entwickelten deutlich weniger und P1, Gisela 5, Gi 195/20 sowie Gi 497/8 keine Wurzelschosser. Den frühesten Blühbeginn induzierte Gisela 4. Die anderen Unterlagen führten, in Abhängigkeit von den Temperaturbedingungen des jeweiligen Jahres, zu einer Verspätung der Blüte: P1 und Weiroot 10 um 1–2 Tage; Gi 497/8, Weiroot 13 und Weiroot 158 um 2–4 Tage; Weiroot 72 um 2–7 Tage; Gi 195/20 um 3–6 Tage; Weiroot 53 um 3–8 Tage und Gisela 5 um 3–10 Tage. Die Reifezeit der Früchte war bei den Bäumen auf Gisela 5 im Vergleich zu den anderen Varianten um 2–3 Tage verspätet. Gisela 5, Weiroot 72 und Gisela 4 induzierten bei der aufveredelten Sorte die höchsten Ertragsleistungen, P1 die geringsten. Bei den Bäumen auf Gisela 5 war die Fruchtgröße geringer als bei den anderen Unterlagen. Bäume auf Gisela 5 brauchen intensive Pflege. Nur wenn alle Produktionsfaktoren und kulturtechnischen Maßnahmen optimiert werden, kann das hohe Ertragspotenzial dieser Unterlage ausgeschöpft werden.  相似文献   

19.
We tested whether size of habitat patches and distance between patches are sufficient to predict the distribution of the mountain vizcacha Lagidium viscacia a large, rock-dwelling rodent of the Patagonian steppe Argentina, or whether information on other patch and landscape characteristics also is required. A logistic regression model including the distance between rock crevices and depth of crevices, distance between a patch and the nearest occupied patch, and whether or not there was a river separating it from the nearest occupied patch was a better predictor of patch occupancy by mountain vizcachas than was a model based only on patch size and distance between patches. Our results indicate that a simple metapopulation analysis based on size of habitat patches and distance between patches may not provide an accurate representation of regional population dynamics if patches vary in habitat quality independently of patch size and features in the matrix alter connectivity. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

20.
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