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1.
When apples which develop low temperature breakdown (LTB) at 32° F. are moved from 32° F. to 65° F. for 3 to 5 days at about the 7th to 8th week of storage, they subsequently develop within a given period of storage less LTB than apples kept at 32° F. continuously.

The respiration of apples susceptible to LTB increases steadily during storage at 32° F. If these apples are warmed to 65° F. during the period of exposure to 32° F., the subsequent rate of respiration at 32° F. is lower than before warming, and continues at a lower rate than for apples kept at 32° F. continuously.

If the apples are moved to 38° F., without an intermediate treatment at 65° F., the rate of respiration is higher than for apples at 38° F. continuously, and this higher rate persists.

If there is an intermediate wanning period at 65° F., the respiration of apples moved from 32° to 38° F. is of the same order as that for apples kept at 38° F. continuously.

The respiratory quotient of apples at 32° F. or at 38° F., which is indicative of the type of respiratory activity, is typical for the temperature at which it is measured, and is not affected by the warming treatment. The effects of wanning on both the incidence of LTB and respiration are similar for apples stored in air and in 2% oxygen: 98% nitrogen.  相似文献   

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The effect of carbon and nitrogen sources, pH, temperature and substrate water content on the growth and vigor of Sparassis crispa mycelium was evaluated. Mycelial growth rates were highest when rice starch served as the carbon source and when peptone, yeast extract or soybean meal were adopted as the nitrogen source. The optimum pH and substrate water content values were 5.25 and 62.5% respectively. Mycelial growth was optimal at 20.2 ℃ and inhibited at 35 ℃, and temperatures of 40 ℃ and above killed the fungus.  相似文献   

4.
AIM: α-MSH is elevated in patients with inflammatory bowel disease and has been implicated as an inflammatory mediator. The purpose of this study was to investigate effects of α-MSH on the Ca2+ channels of primary DMNV cells, the effects of gastrointestinal inflammation on the dorsal motor nucleus of the vagus in rats, as well as the effects of proinflammatory cytokines and α-MSH on neurons from the dorsal motor nucleus of the vagus in vitro. METHODS: In vitro studies the primary culture of neurons from the dorsal motor nucleus of the vagus was performed. Single-cell cytoplasmic calcium transients were determined using the fluorescence dye fura-2-AM. Cell proliferation and apoptosis were measured by enzyme-linked immunosorbent assay. RESULTS: MC4R mRNA was expressed in the DMNV cells of normal rats. Activation of MC4R promoted the calcium influx of primary DMNV cells. The addition of α-MSH to thrombin or trypsin resulted in significant decreases in apoptosis compared to thrombin or trypsin alone. CONCLUSION: Functionally active α-MSH receptors are linked to Ca2+ channels in DMNV neurons. In cultured DMNV cells, α-MSH attenuates neuronal apoptosis and reverses inhibition of cellular proliferation.  相似文献   

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AIM: To investigate the effects of a 10-weeks treatment with angiotensin Ⅱ (Ang Ⅱ) subtype I receptor antagonist losartan on vascular remodeling of thoracic aorta in male spontaneously hypertensive rats (SHR). METHODS: SHR were treated from 16 to 26 weeks of age with losartan at 15 mg/kg·d-1 or 0.75 mg/kg·d-1. RESULTS: Losartan (15 mg/kg·d-1) treatment significantly decreased systolic blood pressure compared with the control group, while losartan (0.75 mg/kg·d-1) had no the effect, losartan(15 mg) prevents the development of aortic hypertrophy by preventing hypertrophy of vascular smooth muscle cells (VSMC). In the losartan 0.75 group, these parameters were not changed. But in the losartan 15 and losartan 0.75 groups, the collagen content of the aortic media decreased significantly. CONCLUSION: It is inferred that the effect of Ang Ⅱ on stimulating VSMC growth of the aorta in SHR is dependent on arterial pressure, while the effect on collagen fibers is through pressure independent mechanism.  相似文献   

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以观赏凤梨“丹尼斯”为试材,研究了不同催花剂处理对观赏凤梨“丹尼斯”内源激素含量的影响.结果表明:不同催花剂处理后,“丹尼斯”凤梨植株体内的IAA含量呈下降趋势,ZRs含量呈增加趋势.说明催花剂能抑制内源IAA的产生,促进内源ZRs的产生.以乙炔气体饱和溶液处理效果最明显.  相似文献   

9.
The distribution of dry matter between the different bulblets of tulip is not markedly influenced by either changes in leaf area or the position of the leaf. On the contrary, total bulb yield is strongly affected.A reduction factor, Sc, for incomplete soil coverage, when the leaf area index (LAI) is less than 4, normally used for evaluation of planting density effects, can also be used for the effects of defoliation on dry matter increase. This LAI-dependent factor shows a distinctly asymptotic pathway closely resembling
Sc=PactPpot=1?e?k1LAI
where k ~ 0.6 and in which Pact is the actual measured dry weight increase and P?pot the potential net dry weight increase for a closed canopy.  相似文献   

10.
Summary

Yield and fruit quality parameters were studied during three years in a rootstock trial with ‘Mutsu’ apple. M.9 provided the highest total yield per tree as well as the highest quantity of intermediate and yellow fruit as compared with J.9, M.26 and B.9. Within similar colour categories, significant differences among rootstocks were also recorded for fruit starch degradation pattern (SDP), firmness, titratable acidity (TA), and soluble solids concentrations (SSC). Generally, the lowest SDP and highest fruit firmness was found in fruits from trees on rootstocks M.26 and B.9. The highest TA was found in fruits from trees on rootstocks M.26 and J.9 and the highest SSC in fruits from trees on rootstocks J.9 and B.9. However, considerable variations among years were also recorded. Correlation coefficients between rootstock and several yield and quality parameters revealed high correlation to SSC for green fruit and TA for medium and yellow fruit and some correlation to yield and number of fruits per tree.  相似文献   

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AIM:To investigate the effect of inwardly rectifying potassium channel (IK1) agonist zacopride (Zac) on angiotensin Ⅱ (Ang Ⅱ)-induced viability and apoptosis of cardiac fibroblasts (CFb) and to explore the underlying anti-fibrosis mechanism.METHODS:The ventricular fibroblasts from neonatal SD rats were isolated and cultured by tissue digestion and differential adherence methods. The model of rat cardiac fibroblast activation induced by angiotensin Ⅱ was established. The CFb were randomly divided into control group, Ang Ⅱ model group, Ang Ⅱ+Zac group, Ang Ⅱ+Zac+BaCl2 group, AngⅡ+Zac+chloroquine group and Ang Ⅱ+captopril group. CCK-8 assay was used to detect the effect of Zac on the viability of CFb. The amount of collagen I and collagen Ⅲ secreted by CFb was determined by ELISA. The apoptosis of the CFb was analyzed by flow cytometry. The protein expression of Kir2.1 was determined by Western blot. RESULTS:Compared with the control group, the viability and collagen synthesis of the CFb were significantly increased, along with decreased Kir2.1 expression (P<0.05). Compared with the Ang Ⅱ model group, Zac treatment inhibited the viability and collagen synthesis of the CFb, induced apoptosis and up-regulated Kir2.1 expression (P<0.05). IK1 blockers BaCl2 and chloroquine reversed the effect of Zac. CONCLUSION:By enhancing IK1 (Kir2.1) expression, Zac attenuates Ang Ⅱ-induced ventricular fibrosis, in response to the inhibition of cell viability and induction of apoptosis.  相似文献   

12.
The effect of temperature on germination and days taken for germination was evaluated in Carica papaya cvs., ‘Pune selection-3’ and ‘Pusa Dwarf’. The highest average seed germination per cent was observed in the month of July (96.8 and 93.0?%), followed by August (94 and 88.5?%), whereas the lowest average seed germination was observed in the month of January (44.2 and 36.8?%) in ‘Pune selection-3’ and ‘Pusa Dwarf’, respectively. Minimum number of days (5.17 and 6.33) was observed for germination in the month of July, whereas the maximum number of days (29.5 and 31) was taken in the month of January in both the cultivars, respectively. The average highest germination and seedling height was observed at temperature 29.8 °C and 29.5 °C during July and August, respectively, whereas the lowest was observed at temperature 14 °C and 15.9 °C during January and December, respectively. The optimum time for nursery sowing was July to August for autumn season crop under subtropical conditions of India.  相似文献   

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This study was carried out in Arsin (Trabzon/Turkey) in 2011. The effects of different harvest time and altitudes on the quality of the nuts have been investigated. The study was performed on Fo?a hazelnut and the harvest process has been conducted at three terms, which are on normal harvest time and ten days before and after harvest time. The harvested nuts were dried in the shade on the concrete floor until their moisture content decreased to 5?%. Some properties of nuts including yield, fruit weight, internal weight, shell thickness, and protein, oleic, and linoleic acid amounts have been investigated. As evaluated all of the fruit properties it can be concluded that 11 August is the most suitable harvest date for coast zone. On the other hand, no significant differences were obtained in the point of protein, oleic, and linoleic acid amounts for different harvest time and altitudes.  相似文献   

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AIM:To evaluate the biological roles of TNF-α on the cartilage endplate cells (chondrocytes). METHODS:The chondrocytes were isolated and harvested from the cartilage endplate of New Zealand rabbits and then the biological characteristics of cells were identified by methods such as toluidine blue staining for type Ⅱ collagen. After different concentrations of TNF-α were added to culture medium respectively, the rate of the proliferation of chondrocytes in different time was measured with MTT. The protein expressions of Bax, Bcl-2, Fas and caspase-3 were measured by immunocytochemistry. The changes of the mRNA of aggrecan and type Ⅱ collagen were measured by RT-PCR. RESULTS:The TNF-α at concentration of 50 μg/L and 100 μg/L decreased the rate of the proliferation on chondrocytes. Though TNF-α at concentrations of 10 μg/L and 50 μg/L increased the level of Bax, Fas and caspase-3, only 50 μg/L TNF-α decreased the level of Bcl-2. TNF-α at concentrations of 10 μg/L and 50 μg/L decreased the level of collagen IIa mRNA and only 50 μg/L TNF-α decreased the level of aggrecan. CONCLUSION:TNF-α not only inhibits the proliferation and the matrix synthesis in chondrocytes, but also increases the expression of pro-apoptotic factors in chondrocytes.  相似文献   

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AIM: To investigate the effect of aldosterone (ALD) on the mRNA expression of angiotensin Ⅱ (Ang II) type 1 (AT-1a R and AT-1bR) and 2 (AT-2R) receptors in cultured rat mesangial cells (RMCs) treated with high glucose. METHODS: Rat mesangial cells were cultured in high glucose medium containing different concentrations of ALD (10-8-10-6 mol/L). The antagonists of ALD and Ang II receptors including pironolactone (10-7 mol/L, aldosterone receptor antagonist, SPI), losartan (10-7 mol/L, Ang II type 1 receptor blocker, Los) or PD123319 (10-9 mol/L, Ang II type 2 receptor antagonist, PD) were added in the cell culture for 12 h. The control cells were only treated with high (30 mmol/L) or normal (5.6 mmol/L) glucose medium. The viability and proliferation of the RMCs were evaluated by MTT assay. The mRNA expression of AT-1aR, AT-1b R and AT-2R was detected by semi-quantitative RT- PCR. The expression of MCP-1 in cultured RMCs was detected by ELISA. RESULTS: The mRNA expression of AT-1aR, AT-1b R and AT-2R was increased significantly by treatment with ALD in a dose-dependent manner (1.62-1.77, 9.61-9.89 and 7.26-7.35 folds of high glucose control, respectively, P<0.01). SPI significantly reduced the mRNA expression of AT-1aR and AT-1b R (P<0.01) but not affected the mRNA expression of AT-2R. The ratio of AT-1aR/AT-1b R in cultured RMCs treated with high glucose decreased significantly after stimulated with ALD (P<0.01). However, the effect of ALD was inhibited by SPI (P<0.01). Aldosterone treatment induced a significant upregulation of MCP-1 expression in a dose-dependent manner, and previous treatment with spironolactone, losartan or PD123319 abolished this aldosterone-induced MCP-1 expression. CONCLUSION: The results suggest that aldosterone is involved in the inflammatory response by up-regulating the expression of AT-1aR, AT-1bR and AT-2R, changing the proportion of AT-1R subtype, and inducing MCP-1 overproduction in cultured RMCs treated with high glucose.  相似文献   

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AIM: To investigate the effect of Buyanghuanwu decoction, a Chinese medicine, on the ability of learning and memory in the rats with vascular dementia (VD) and on the protein expression of extracellular signal-regulated kinase 2(ERK2) and calcium/calmodulin-dependent protein kinase Ⅱβ(CaMKⅡβ) in hippocampus CA1 area.METHODS: The rats were divided into 4 groups: sham group, VD group, VD+Buyanghuanwu decoction group and VD+nimodipine group. The VD rat model was prepared by Pulsinelli's four-vessel occlusion. At 7th day, 14th day or 28th day after operation, the behaviors of the rats were tested by Morris water maze. The morphological changes of the neurons in hippocampus CA1 area were observed by HE staining 30 d after operation. Western blotting was used to observe the protein expression of ERK2 and CaMKⅡβ in the brain tissues of hippocampal CA1 area of the VD rats. RESULTS: Compared with sham group, the pathological changes such as irregular arrangement, coagulation necrosis and obvious deletion in the neurons of hippocampus CA1 area in VD group appeared significantly. The obstacle of learning and memory ability was observed and the protein expression of ERK2 and CaMKⅡβ in hippocampal CA1 area was significantly decreased (P<0.05). Compared with VD group, the neurons in hippocampal CA1 area of VD+Buyanghuanwu decoction group and VD+nimodipine group were in eumorphism, lined up in order, and the structure was close to that in sham group. The ability of learning and memory also significantly improved (P<0.05). The protein expression of ERK2 and CaMKⅡβ in hippocampal CA1 area significantly increased (P<0.05). CONCLUSION: Buyanghuanwu decoction promotes the protein expression of ERK2 and CaMKⅡβ in hippocampus CA1 area to protect the neurons from injury, builds up the synapses and promotes the ability of learning and memory in VD rats.  相似文献   

17.
Shen W.  Zhu W.  Zeng C.  He H.  Li G.  Liu J. 《果树学报》2022,(5):752-763
【Objective】Peach (Prunus persica) is an economically important fruit crop worldwide. With the increasing demand and the reduced cultivated land acreage of peach, replant problem (also known as replant disease) has become increasingly prominent, and has been causing severe economic losses. Autotoxicity is a special kind of allelopathy, and is considered to be a major factor resulting in the prevalence of peach replant problem. Cyanide (CN-) is a major autotoxin that causes peach replant problem, but the information on physiological and metabolic responses of peach plants under CN- treatment is quite limited. Thus, the specific responsive mechanisms of peach plants to CN- are worthy of in-depth exploration. The study aimed to investigate the effects of CN- treatment on the morphological, physiological, and metabolic parameters in roots of peach seedlings, so as to provide new insights into the response mechanisms of peach plants to CN- treatment. 【Methods】The natural root environment of dead and living trees was investigated in the peach orchard of Huazhong Agricultural University. The effects of exogenous CN- treatment on root growth and seed germination were assessed on peach germinatedseeds (treated with 0, 0.25, 0.5, and 1.0 mmol•L-1 CN-) and lettuce seeds (treated with 0 and 0.5 mmol•L-1 CN- ). The peach root tips treated with 0 and 0.5 mmol • L-1 CN- were subjected to anatomical assessments using paraffin sectioning and staining (including transverse and longitudinal sections). The contents of H2O2 and MDA, as well as the activities of CAT, POD, and SOD from 0 and 0.5 mmol•L-1 CNstressed peach roots were detected. The expression levels of CAT, POD, and SOD-encoding genes were tested using qRT-PCR. To further understand the CN- -induced metabolic changes, peach roots treated with 0 and 0.5 mmol • L-1 CN- for 5 d were subjected to gas chromatography-mass spectrometry (GCMS) analysis. 【Results】The CN- was mainly distributed in 0-40 cm soil layer, and the content was significantly higher in the soil with dead trees than with living trees. The CN- content in soil was predominantly detected adjacent to peach roots, and gradually decreased with the distance from peach roots. The CN- contents showed an upward trend year by year in the bulk soils with the dead and living trees, where the dead trees contained more CN- than the living trees. The CN- contents varied in different size of peach roots, the fine roots (Φ < 5 mm) contained more CN- than the middle size (5 mm ≤ Φ ≤ 10 mm) and the large size roots (Φ > 10 mm). We evaluated the effect of different CN- concentrations (0, 0.25, 0.5, and 1.0 mmol•L-1) on the growth performance of peach germinated-seeds. The result showed that 0.25 mmol • L-1 CN- treatment boosted root growth, while 0.5 and 1.0 mmol • L-1 inhibited root growth with decreased root length and lateral root numbers. The allelopathy sensitivity index indicated that the effects of CN- treatment on peach growth in a concentration-dependent manner, showing low concentration promoted growth but high concentration inhibited it. Additionally, with 0.5 mmol•L-1 CNtreatment, the transverse and longitudinal sections of the root tip showed a severely wrinkled root epidermis, ruptured root cortex cells, and larger intercellular spaces. 0.5 mmol•L-1 CN- treatment also significantly inhibited lettuce seed germination and biomass. The contents of H2O2 and MDA in peach roots significantly increased, and the activities of SOD, POD, and CAT, as well as their respective encoding genes expression, significantly increased with 0.5 mmol•L-1 CN- treatment. The GC-MS analysis showed that 0.5 mmol • L-1CN- treatment dramatically increased contents of numerous amino acids, including proline, glycine, serine, asparagine, alanine, glutamate, GABA etc. Moreover, CN- treatment significantly affected carbohydrate levels in peach roots. 【Conclusion】The CN- contents were associated with the distribution and size of plant roots, and the decomposition of plant residuals. Exogenous CNsupply markedly retarded peach root growth. CN- feeding also gave rise to oxidative stress, reflecting by the increased ROS and MDA levels, and antioxidant enzyme activities. CN- supplementation also induced metabolic reprogramming, displaying a disorder of amino acid and carbohydrates metabolism. © 2022, Office of Journal of the Fruit Science. All right reserved.  相似文献   

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AIM:To investigate the effect of peroxisome proliferator-activated receptor δ (PPARδ) activation with dietary GW610742X on the expression of matrix metalloproteinase-9 (MMP-9) and fibronectin (FN) in infarcted and remodeling myocardium. METHODS: Wistar rats were divided into 4 groups: control group, sham group, myocardial infarction (MI) group and MI+GW610742X (GW) group. The left coronary artery was ligated to establish the MI model. PPARδ activator GW610742X (100 mg·kg-1·d-1) was given to the rats in GW group. At the 3rd month of the procedure, the expression of PPARδ, MMP-9 and FN at mRNA and protein levels in the left ventricular free wall(LVFW) of the heart from each group was identified and the distribution of FN was detected by immunofluorescence. RESULTS: After 3 months following the procedure, obvious necrosis and fibrosis in LVFW were observed in MI group. The expression of PPARδ in MI group was higher than that in control, sham and GW groups (P<0.01), and PPARδ expression in GW group was lower than that in control and sham group (P<0.05). In MI and GW groups, the expression of MMP-9 was higher while the expression of FN was lower than those in control and sham group (P<0.05 or P<0.01). In GW group, the expression of MMP-9 was lower (P<0.05) while the expression of FN was higher (P<0.01) than those in MI group. Meanwhile, the expression of MMP-9 and FN in sham group was similar to those in control group (P>0.05). CONCLUSION: MMP-9 is upregulated and FN is downregulated in infarcted myocardium during the remodeling process. Activation of PPARδ inhibits the upregulation of MMP-9 and degradation of FN, thus ameliorating the myocardial remodeling.  相似文献   

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XU Hua  CHEN Li-jun 《园艺学报》2012,28(5):829-833
AIM: To investigate the effect of peroxisome proliferator-activated receptor γ(PPARγ) on the invasion ability of trophoblasts. METHODS: A segment of PPARγ siRNA was synthesized. Three groups were designed: experiment group, negative control group and blank control group. The PPARγ siRNA was transfected into JEG-3 cells. Real-time quantitive PCR was used to detect the mRNA levels of PPARγ and mucin-1(MUC1). The Transwell culture inserts were used to detect the invasion ability of JEG-3 cells 24 h after treated with PPARγ siRNA. RESULTS: After transfected with PPARγ siRNA, the mRNA expression levels of PPARγ and MUC1 were significantly depressed by (75.0±0.8)% and (65.0±1.3)% (P<0.05),respectively, and the invasion ability of JEG-3 cells was significantly strengthened (P<0.05). CONCLUSION: The depression of PPARγ gene down-regulates the expression of MUC1, and affects the invasion ability of trophoblasts, indicating that PPARγ may regulate the invasion of trophoblasts by MUC1 and involve in the development of placental defects such as preeclampsia.  相似文献   

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