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161.
[目的]对昆明6个蓝莓品种进行了冻害情况调查,为该地区蓝莓引种及防寒工作提供参考。[方法]调查研究南高丛蓝莓品种(奥尼尔、夏普蓝、密斯黛)和兔眼蓝莓品种(顶峰、灿烂、梯芙蓝)共6个蓝莓品种受低温冻害的情况。[结果]3个南高丛蓝莓品种冻害率均达到100%,3个兔眼蓝莓品种中,灿烂冻害率高达75.0%,梯芙蓝冻害率仅为16.7%,顶峰植株未遭冻害。奥尼尔和灿烂品种受冻害的器官主要为花和果,其余3个品种受低温冻害的器官不同。[结论]不同蓝莓品种具有不同的抗寒力,露天栽培中可优先考虑顶峰和梯芙蓝品种。 相似文献
162.
Field experiments were conducted during 2009 and 2010 to evaluate the effects of defoliation on maturity group IV soybeans, Glycine max (L.) Merr., grown in Mississippi. During each year, two locations were planted with maturity group IV soybeans that were subjected to various levels of defoliation during R3, R5, and R6 growth stages. Soybeans were subjected to various levels of defoliation within the upper 50% of the plant canopy, lower 50% of the plant canopy, and whole-plant canopy. There was greater yield loss from defoliation occurring in the upper plant canopy compared with the lower plant canopy during R3 and R5 stages, but no difference between canopy regions during R6 stage. Yield loss from whole plant defoliation was greater than upper or lower canopy defoliation. Results confirmed that soybeans during R3 and R5 stages are more susceptible to yield loss than during R6. However, yield losses were not significantly different between R 3 and R5 until defoliation exceeded 63%. Dynamic economic injury levels were determined for each growth stage based on yield loss equations, value of the crop, and cost of control and can be used as a basis for developing action thresholds in high-yielding soybean production environments. 相似文献
163.
164.
Rupture of the suspensory ligament at the insertions on the proximal sesamoid bones, and of the superficial flexor tendon of the left fore limb, occurred in an adult Angus bull as a result of fighting. There was severe hyperextension of the metacarpophalangeal (MCP) joint with the dewclaws almost touching the ground. Radiographs revealed severe hyper-extension of the MCP joint with the sesamoid bones aligned directly distal to the metacarpus. Initially, a full length fiberglass cast was applied with the limb partially flexed within the cast and the heels elevated. The cast was replaced twice. The cast was removed after 136 days and the bull was bearing full weight on the limb. Prolonged immobilisation of the limb produced new bone in the area (a normal response in cattle) to cause ankylosis of the traumatized MCP joint and partial ankylosis of the carpus. The bull was being used for pasture breeding one year after the injury. 相似文献
165.
Dez Hughes BVSc MRCVS R. E. Moreau DVM K. L. Overall VMD T. J. Van Winkle VMD 《Journal of Veterinary Emergency and Critical Care》1996,6(1):13-20
A retrospective analysis was conducted of all feline necropsies performed during a nine year period to identify cases of sever, acute, centrilobular (periacinar), hepatic necrosis (ACHN). After exclusion of cats with anemia, a series of seven cases of ACHN was identified. In addition, two similar cases were identified from tissue submitted for histopathology following, and eight had bile duct hyperplasia. Seven of the nine cats received diazepam prior to dath, and one received zolazepam. Of the seven cats that received diazepam, five were healthy prior to treatment and received oral diazepam for the treatment of inappropriate urination, intercat aggression, or skin disease. Two cats which received diazepam exhibited other clinical signs: one had chronic vomiting, and the other received diazepam after biochemical evidence of hepatocellular necrosis was present. Onset of clinical sings in cats receiving oral diazepam occurred 7–13 days following the initiation of treatment. Clinical signs and clinical biochemical analysis were compatible with severe hepatocellular necrosis and acute liver failure. All cats had lesions in other organs: five had pancreatic disease, five had cardiac disease, and five had renal disease. All cats died, or were euthanized, within 4 dyas of the onset of clinical signs and 2 days after presentation to a veterinarian. Fatal, acute, centrilobular hepatic necrosis appears to be a serious adverse reaction to diazepam therapy in certain cats. 相似文献
166.
间歇升温对芒果冷害及生理生化反应的影响 总被引:23,自引:3,他引:20
对低温贮藏中的芒果进行间歇升温处理,结果表明:间歇升温处理延迟了2℃贮藏果冷害引起的乙烯释放及呼吸强度的上升,延迟了果皮多胺水平的上升,使果皮的SOD活性维持在较高水平,细胞膜透性增加缓慢,从而显著提高了芒果的抗冷害能力。但间歇升温处理使10℃贮藏果乙烯释放高峰及呼吸高峰提前且峰高增加,果皮SOD活性降低,果皮细胞膜透性增大,从而促进了芒果的成熟衰老。 相似文献
167.
本研究旨在探讨围产期窒息时内皮素( ET)和一氧化氮 ( NO)的变化与急性胃黏膜损伤的关系及 NO的前体 L-精氨酸 ( L-Arg)和NO合成酶抑制剂 L-硝基 -精氨酸甲酯 ( L-NAME)在胃黏膜损伤中的作用。结果显示窒息组血浆 ET和胃壁 NO水平显著高于正常对照组 ( p<0 .0 1 ) ,胃黏膜损伤明显 ;L -Arg组血浆ET水平较窒息组显著下降 ( p <0 .0 1 ) ,血浆和胃壁 NO含量则显著升高 ( p <0 .0 1 ) ,胃黏膜损伤减轻 ;L-NAME组血浆 ET水平和 L I显著高于正常对照组和 L -Arg组 ( p <0 .0 1 ) ,血浆和胃壁 NO含量较 L-Arg组显著下降 ( p <0 .0 1 ) ,表明围产期窒息时 NO和 ET的变化与胃黏膜损伤的程度密切相关。NO在围产期窒息时有保护胃黏膜的作用 ,而 ET则作用相反。L -Arg的保护作用和 L -NAME的损伤作用均是通过 NO的变化来实现的。 相似文献
168.
YAN Rui SHAN Hu LIN Lin DIAO Jia-yu ZHANG Ming ZHU Yan-he TAN Wu-hong WEI Jin 《园艺学报》2015,31(6):967-972
AIM: To observe the effect of high glucose on the protein expression of calreticulin (CRT) and its association with cell apoptosis and mitochondrial dysfunction in the cardiomyocytes. METHODS: AC-16 cardiomyocytes were randomly divided into normal glucose group, high glucose group, high glucose+ CRT siRNA group and isotonic control group. The cell apoptotic rate, reactive oxygen species (ROS), mitochondrial membrane potential level, respiratory enzyme activity, and protein expression of CRT were observed. RESULTS: Compared with the cardiomyocytes in normal glucose group, the apoptotic rate and ROS production of cardiomyocytes increased in high glucose group, accompanying with the decreases in the mitochondrial membrane potential level and enzyme activitiy of the respiratory chain. The protein expression of CRT was significantly increased in high glucose group. However, compared with high glucose group, high glucose+ CRT siRNA decreased the expression of CRT and attenuated the damage of mitochondria, but CRT siRNA did not reduce the ROS level in cardiomyocytes. CONCLUSION: High glucose brings about CRT over-expression to induce mitochondrial injury, thus increasing myocardial apoptosis. 相似文献
169.
AIM: To investigate the protective effect of pinacidil postconditioning on rat myocardium suffering ischemia/reperfusion injury by mitochondrial proteomics. METHODS: Langendorff apparatus was used to establish the model of myocardial ischemia/reperfusion injury. Sprague-Dawley rats were randomly divided into 2 groups: pinacidil postconditioning group (Pina group) and ischemia/reperfusion injury group (I/R group). After 20 min of perfusion with K-H solution, the perfusion was suspended for 40-min (global ischemia) follow by 60 min of reperfusion in I/R group. In Pina group at the end of 40 min global ischemia, the isolated hearts were perfused with K-H solution containing pinacidil (50 μmol/L) for 2 min followed 58-min perfusion with regular K-H solution. Total proteins extracted from the mitochondria were applied to the two-dimensional gel electrophoresis (2-DE). The differentially expressed protein spots over 2 times were evaluated by a software. Then they were subjected to in-gel digestion, and analyzed by spectrometry. RESULTS: The expression levels of NDUFA10, NDUFS2 and NDUFV2 were elevated but those of IDHA and ECH1 were decreased in Pina group compared with I/R group. Interestingly, 2 spots in the 2-DE map were identified as ATPase subunit δ. The expression levels of one spot was elevated, while the other was decreased. CONCLUSION: Pinacidil postconditioning may decrease the degree of increased expression levels of NDUFA10, NDUFS2 and NDUFV2, promote the expression of IDHA and ECH1, and induce the phosphorylation of ATPase subunit δ, which may be related to the protective mechanism of pinacidil postconditioning. 相似文献
170.
AIM: To investigate the effects and mechanisms of sphingosine-1-phosphate receptor-2 (S1P2R)on lipopolysaccharide (LPS)-induced acute lung injury (ALI). METHODS: ALI model was induced by intratracheal administration of LPS in both wild-type mice and S1P2R -deficient mice. The pathological changes in the lung tissues were observed, and the protein concentration, total cell number, neutrophil ratio, TNF-α level and IL-6 level were determined in the bronchoalveolar lavage fluid (BALF) 24 h after LPS injection. In order to investigate the mechanisms of S1P2R in LPS-induced ALI, 10 min before LPS injection, both wild-type mice and S1P2R -deficient mice were injected with nitric oxide synthase inhibitor by tail vein injection, the pathological changes of the lung tissues were observed, and the protein concentration and total cell number in BALF were determined 12 h after LPS injection. RESULTS: Compared with wild-type mice, S1P2R -deficient mice showed more severe LPS-induced ALI, and the protein concentration, neutrophils and inflammatory cytokines in BALF were significantly increased in S1P2R -deficient mice. Administration of nitric oxide synthase inhibitor Nω-L-nitro-arginine methyl ester protected S1P2R -deficient mice from aggravation of ALI. CONCLUSION: S1P2R mediates the protection from LPS-induced ALI possibly through inhibiting nitric oxide synthase. 相似文献