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61.
Intergeneric somatic hybrid plants derived from protoplast fusion between Citrus sinensis (L.) Osbeck cv. Valencia and Fortunella crassifolia Swingle cv. Meiwa have been grown in the fields for 6 years. The plants grew less vigorously with uneven canopy size and some shoots frequently died. Chromosome count showed that the plants, containing non-tetraploid cells besides amphidiploid, were chimeras. Most somatic hybrid plants exhibited a new band of EST isozyme. RAPD analysis verified that several plants lacked some of the parents' markers. The results indicated that the intergeneric somatic hybrids were genetically unstable.  相似文献   
62.
Early findings propose that impaired neurotransmission in the brain plays a key role in the pathophysiology of schizophrenia. Recent advances in understanding its multiple etiologies and pathogenetic mechanisms provide more speculative hypotheses focused on even broader somatic systems. Using a targeted tandem mass spectrometry (MS/MS)-based metabolomic platform, we compared metabolic signatures consisting of monoamine and amino acid neurotransmitter (NT) metabolites in plasma/urine simultaneously between first-episode neuroleptic-na?ve schizophrenia patients (FENNS) and healthy controls before and after a 6-week risperidone monotherapy, which suggest that the patient NT profiles are restoring during treatment. To detect and identify potential biomarkers associated with schizophrenia and risperidone treatment, we also performed a combined ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) and (1)H nuclear magnetic resonance (NMR)-based metabolomic profiling of the same samples, indicating a further deviation of the patients' global metabolic profile from that of controls. The NTs and their metabolites together with the 32 identified biomarkers underpin that metabolic pathways including NT metabolism, amino acid metabolism, glucose metabolism, lipid metabolism, energy metabolism, antioxidant defense system, bowel microflora and endocrine system are disturbed in FENNS. Among them, pregnanediol, citrate and α-ketoglutarate (α-KG) were significantly associated with symptomatology of schizophrenia after Bonferroni correction and may be useful biomarkers for monitoring therapeutic efficacy. These findings promise to yield valuable insights into the pathophysiology of schizophrenia and may advance the approach to treatment, diagnosis and disease prevention of schizophrenia and related syndromes.  相似文献   
63.
本文分析比较了正红菇深层培养菌丝体和野生子实体有效成份的含量和组成及抑菌作用。结果表明:正红菇深层培养菌丝体和野生子实体均含有蛋白质、多糖、氨基酸、不饱和脂肪酸、挥发性物质、麦角固醇及抑菌活性物质等多种有效成份,其组成基本一致,但菌丝体在多种成份的含量上略低于子实体。  相似文献   
64.
Angiostatin consisting of the first four-kringle domains of the plasminogen potently inhibits angiogenesis in vitro and in vivo. However, the molecular mechanism of action whereby angiostatin mediates its inhibitory effect on proliferating endothelial cells remains elusive. We therefore used the proliferating cultured human umbilical vein endothelial cells (HUVECs) promoted by vascular endothelial growth factor A to identify the endogenous signaling elements that mediate the antiangiogenic effect of angiostatin. Treatment of HUVEC with angiostatin at a concentration known to inhibit cell proliferation and induce apoptosis resulted in induction of p53-, Bax-, and tBid-mediated release of cytochrome c into the cytosol. In addition, angiostatin also activated the Fas-mediated apoptotic pathway in part via up-regulation of FasL mRNA, down-regulation of c-Flip, and activation of caspase 3. These results suggest that the anti-angiogenic action of angiostatin is likely mediated by two distinct signaling pathways, one intrinsic mediated by p53 while the other extrinsic involved in FasL engagement and mitochondria dysfunction.  相似文献   
65.
A high-performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-MS/ESI) method for simultaneous determination of venlafaxine (VEN) and its three metabolites O-desmethylvenlafaxine (ODV), N-desmethylvenlafaxine (NDV) and N,O-didesmethylvenlafaxine (DDV) in human plasma has been developed and validated. Estazolam was used as the internal standard. The compounds and internal standard were extracted from plasma by a liquid-liquid extraction. The HPLC separation of the analytes was performed on a Thermo BDS HYPERSIL C18 (250 mm x 4.6 mm, 5 microm, USA) column, using a gradient elution program with solvents constituted of water (ammonium acetate: 30 mmol/l, formic acid 2.6 mmol/l and trifluoroacetic acid 0.13 mmol/l) and acetonitrile (60:40, V/V) at a flow-rate of 1.0 ml/min. All of the analytes were eluted within 6 min. The compounds were ionized in the electrospray ionization (ESI) ion source of the mass spectrometer and were detected in the selected ion recording (SIR) mode. Calibration curves in spiked whole blood were linear from 4.0-700 ng/ml, 2.0-900 ng/ml, 3.0-800 ng/ml and 2.0-700 ng/ml for VEN, ODV, NDV and DDV, respectively, all of them with coefficients of determination above 0.9991. The average extraction recoveries for all the four analytes were above 77%. The methodology recoveries were higher than 91%. The limits of detection were 0.4, 0.2, 0.3, and 0.2 ng/ml for VEN, ODV, NDV and DDV, respectively. The intra- and inter-day variation coefficients were less than 11%. The method is accurate, sensitive and reliable for the pharmacokinetic study of venlafaxine as well as therapeutic drug monitoring (TDM).  相似文献   
66.
Cao WH  Liu J  He XJ  Mu RL  Zhou HL  Chen SY  Zhang JS 《Plant physiology》2007,143(2):707-719
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67.
柑桔种间体细胞杂种的花粉特性及贮藏研究   总被引:2,自引:0,他引:2  
对粗柠檬与“哈姆林”甜橙种间体细胞杂种的花粉特性(形态、花粉量、生活力等)进行了观察、检测,并于-20℃的低温条件下开展了贮藏试验。结果表明:花粉离体萌发的适宜培养基为0.8%琼脂 16%蔗糖 10mg/kg硼酸,萌发率为15.31%,其生活力介于两亲本之间,可作为杂交亲本进一步被利用。贮藏试验结果显示:以真空、干燥(CaCl2或硅胶作干燥剂)贮藏花粉的效果较好。授粉试验证明,贮藏花粉与新鲜花粉的座果率差异不显著,说明低温、真空和干燥是贮藏粗柠檬与“哈姆林”甜橙种间体细胞杂种花粉的较适条件。  相似文献   
68.
Both vitamin D (VD) signaling and Nur77 are implicated in dopaminergic neurotransmission and dopamine-related neuropsychiatric disorders, such as schizophrenia and Parkinson’s disease. Developmental vitamin D (DVD) deficiency rats exhibit schizophrenia-like behaviors and disturbance of dopamine system, which could be partly normalized by haloperidol treatment. By blocking dopamine D2 receptor, haloperidol induces Nur77 expression, suggesting a modulatory role of Nur77 in brain dopamine system. Rxr is the heterodimeric partner of both Nur77 and vitamin D receptor and also participates in homeostatic regulation of central dopamine neurotransmission. Although D2 antagonist-induced Nur77 expression has been reported by several studies, the change of its active partner Rxr remains elusive. Here, we studied the impact of 2 weeks administration of haloperidol on VD signaling and Nur77/Rxr expression in rat prefrontal cortex. It was found that haloperidol has no effect on local VD signaling, but could significantly increase Nur77, Rxrβ, and Rxrγ expression, which indicated that Nur77/Rxr, but not vdr/Rxr, was implicated in dopamine-related neuroadaptation. Given that VD deficiency is commonly observed in schizophrenia patients, the renal metabolism of VD was also examined.  相似文献   
69.
青冈常绿阔叶林主要树种叶形基本上都为椭圆形,叶面积在15-40cm2/叶之间,属于中型叶和小型叶;在同一植株上,青冈叶片的大小很好地符合正态分布规律,石栎则近似于负二项分布,甜槠和木荷接近正态分布;主要树种叶的大小是优势种青冈>次优势种石栎>其它伴生种,这在群落结构分化中具有适应意义,即其“生长策略”不同;同一树种叶片大小为中层木叶片>上层木叶片;春夏换叶之前,叶大小和叶重达到第一高峰,秋冬季出现第二峰,叶比重为秋、冬季>春、夏季,这是常绿植物对季节性不利气候(冬季寒冷,夏季高温伏旱)的一种生态适应。  相似文献   
70.

Purpose

To determine the role of thrombomodulin (TM) in corneal epithelial wound healing, and to investigate whether recombinant TM epidermal growth factor-like domain plus serine/threonine-rich domain (rTMD23) has therapeutic potential in corneal epithelial wound healing.

Methods

TM localization and expression in the murine cornea were examined by immunofluorescence staining. TM expression after injury was also studied. The effect of rTMD23 on corneal wound healing was evaluated by in vitro and in vivo assays.

Results

TM was expressed in the cornea in normal adult mice. TM expression increased in the early phase of wound healing and decreased after wound recovery. In the in vitro study, platelet-derived growth factor-BB (PDGF-BB) induced TM expression in murine corneal epithelial cells by mediating E26 transformation-specific sequence-1 (Ets-1) via the mammalian target of rapamycin (mTOR) signaling pathway. The administration of rTMD23 increased the rate of corneal epithelial wound healing.

Conclusions

TM expression in corneal epithelium was modulated during the corneal wound healing process, and may be regulated by PDGF-BB. In addition, rTMD23 has therapeutic potential in corneal injury.  相似文献   
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