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161.
162.
 The processes of megasporogenesis and early megagametogenesis were cytologically investigated in Cupressus sempervirens L. in order to elucidate, at the cellular level, the origin of the megagametophyte. After pollination, sporogenous tissue developed in the chalazal region of the nucellus, but only one megaspore mother cell differentiated and divided meiotically without cell-wall formation. This led to the development of a cell with four nuclei which directly functioned as a megaspore. The C. sempervirens megagametophyte is thus tetrasporic, in contrast to the majority of conifers where the megagametophyte is monosporic. The consequenses of this observation are discussed from a genetics point of view. Received: 15 August 1997 / Accepted: 19 September 1997  相似文献   
163.
大球盖菇硒多糖体内抗氧化能力检测   总被引:2,自引:0,他引:2  
采用液体发酵的方法对大球盖菇菌丝进行富硒培养,提取硒多糖进行抗氧化能力测定.结果表明,大球盖菇硒多糖能明显提高小鼠血中SOD、GSH-Px的含量,能在一定程度上显著降低血中MDA的含量,具有显著的抗氧化功能.  相似文献   
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165.
The objective of this study was to explore the potential role of G-protein-coupled receptor kinase 2 (GRK2) in the progression of cannabinoid 2 receptor (CB2) agonist-induced analgesic effects of bone cancer pain. Female Sprague–Dawley rats, weighing 160–180 g, were utilized to establish a model of bone cancer pain induced by intra-tibia inoculation of Walker 256 mammary gland carcinoma cells. JWH-015, a selective CB2 agonist, was injected intrathecally or intraperitoneally on postoperative day 10. Bone cancer-induced pain behaviors—mechanical allodynia and ambulatory pain—were assessed on postoperative days ?1 (baseline), 4, 7, and 10 and at post-treatment hours 2, 6, 24, 48, and 72. The expressions of spinal CB2 and GRK2 protein were detected by Western Blotting on postoperative days ?1 (baseline), 4, 7, and 10 and at post-treatment hours 6, 24, and 72. The procedure produced prolonged mechanical allodynia, ambulatory pain, and different changes in spinal CB2 and GRK2 expression levels. Intrathecal or intraperitoneal administration of JWH-015 alleviated the induced mechanical allodynia and ambulatory pain, and inhibited the downregulation of spinal GRK2 expression. These effects were in a time-dependent manner and reversed by pretreatment of CB2 selective antagonist AM630. The results affirmed CB2 receptor agonists might serve as new treatment targets for bone cancer pain. Moreover, spinal GRK2 was an important regulator of CB2 receptor agonist-analgesia pathway.  相似文献   
166.
167.
To describe the effects of sodium-glucose co-transporter 2 (SGLT2) inhibitors on serum uric acid (SUA) in patients with type 2 diabetes mellitus (T2DM). PubMed, EMBASE, and CENTRAL were searched for randomized controlled trials of SGLT2 inhibitors in patients with T2DM up to Aug 10, 2017, without language or date restrictions. Thirty-one studies totaling 13,650 patients were included. SGLT2 inhibitors significantly decreased SUA levels compared with placebo, canagliflozin WMD –37.02?μmol/L, 95% CI [–38.41, –35.63], dapagliflozin WMD –38.05?μmol/L, 95% CI [–44.47, –31.62], empagliflozin WMD –42.07?μmol/L, 95% CI [–46.27, –37.86]. The drug class effect of SUA reduction suggesting SGLT2 inhibitors might be beneficial for diabetic patients with hyperuricemia.  相似文献   
168.
Animal cloning can be achieved by somatic cell nuclear transfer(SCNT), but the resulting live birth rate is relatively low. We previously improved the efficiency of bovine SCNT by exogenous melatonin treatment or by overexpression of lysine-specific demethylase 4D(KDM4D) and 4E(KDM4E). In this study, we revealed abundant alternative splicing(AS) transitions during fertilization and embryonic genome activation, and demonstrated abnormal AS in bovine SCNT embryos compared with in vitro fertilized ...  相似文献   
169.
Li  Wen-Ru  Ma  Yong-Kai  Shi  Qing-Shan  Xie  Xiao-Bao  Sun  Ting-Li  Peng  Hong  Huang  Xiao-Mo 《Applied microbiology and biotechnology》2018,102(17):7555-7564
Applied Microbiology and Biotechnology - Garlic oil can disrupt the quorum sensing (QS) pathways of the opportunistic pathogen Pseudomonas aeruginosa; however, the underlying mechanisms for this...  相似文献   
170.
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