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101.
This study reports maximum parsimony and Bayesian phylogenetic analyses of selected Old World Astragalus using two chloroplast fragments including trnL-F and ndhF and the nuclear ribosomal internal transcribed spacer (nrDNA ITS). A total of 52 taxa including 34 euploid Old World and New World Astragalus , one aneuploid species from the Neo-Astragalus clade as a representative and 14 other Astragalean taxa, plus Cheseneya astragalina and two species of Caragana as outgroups were analyzed for both trnL-F and nrDNA ITS regions. ndhF was analyzed in 30 taxa and the same number for the combination of these three datasets were examined. In general, the trnL-F dataset and the ndhF and nrDNA ITS datasets generated more or less the same clades within Astragalus . However, in the trnL-F and ndhF phylogenies, Astragalus species are not gathered in a single clade, the so-called Astragalus s.s., as indicated by the nrDNA ITS tree. Visual inspection of these three phylogenies revealed that they were inconsistent regarding the position and relationships of Astragalus hemsleyi , A. ophiocarpus , A. annularis–A. epiglottis / Astragalus pelecinus, A. echinatus and A. arizonicus . Incongruence length difference test suggested that the trnL-F , ndhF and nrDNA ITS datasets were incongruent. In spite of this, phylogenetic analyses of the combined datasets as one unit or as three partitions generated trees that were topologically similar as a mix of the cpDNA and the nrDNA ITS trees. However, the combined dataset provided more resolved and statistically supported clades. The recently described A. memoriosus appeared closely related to A. stocksii (both from sect. Caraganella ) based on both trnL-F and nrDNA ITS sequences.  相似文献   
102.
In this study, nanoniosome‐loaded Myristica fragrans'' (MF) phenolic compounds (NLMP) were synthesized and characterized for their physical properties, and hepatoprotective effects on mice with liver toxicity induced by L‐asparaginase (LA) injection. According to the results, NLMP has a spherical shape with a 263 nm diameter, a zeta potential of −26.55 mV and a polydispersity index (PDI) of 0.192. The weight and feed intake of mice induced with hepatotoxicity were significantly (p ≤ 0.05) increased after they were treated with NLMP (2.5 mg/kg body weight of mice). In addition, the blood levels of triglyceride (TG), cholesterol (Chol), liver enzymes (aspartate aminotransferase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP)) and total bilirubin were significantly (p ≤ 0.05) decreased. A significant increase (p ≤ 0.05) in the blood levels of the antioxidant defence system (glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT)) were also reported after NLMP treatment. NLMP was also led to a significant decrease (p ≤ 0.05) in inflammatory‐related gene expression of inducible nitric oxide synthase (iNOS) and Interferon‐gamma (IFN‐γ) in the liver, as well as a meaningful (p ≤ 0.05) increase in the expression of SOD as an antioxidant status biomarker. Consequently, the NLMP is recommended as a potential dietary supplement to alleviate the symptoms of LA‐induced hepatotoxicity.  相似文献   
103.
The known effects of calcium channel blockers on various aspects of potassium homeostasis are reviewed. Regulation of potassium homeostasis requires both renal and external handling mechanisms. Signaling by calcium appears to mediate both of these. Calcium channels have been identified in adrenal glomerulosa cells, and cellular calcium entry has been demonstrated in vitro to be necessary for the synthesis and secretion of aldosterone. Calcium channel antagonists such as verapamil and nifedipine, at pharmacologic doses, can block aldosterone production. In vivo, however, only chronic administration of verapamil appears to attenuate aldosterone responsiveness to angiotensin II. Chronic administration of nifedipine does not have a dramatic effect on aldosterone production following potassium loading. Other studies have demonstrated improved extrarenal potassium disposal following treatment with calcium channel blocking agents. Clinically, there are no reports of either hyperkalemia or hypokalemia with the routine therapeutic use of these agents given alone. This review was prompted by the development of hyperkalemia in a patient with chronic renal failure following the initiation of therapy with the calcium channel blocker diltiazem: however, numerous other etiologies may also have contributed to the development of hyperkalemia in this case. Review of the data indicates that current evidence implicating this class of drugs in the pathogenesis of disordered potassium regulation remains equivocal.  相似文献   
104.
Journal of Plant Growth Regulation - Destruction caused by plant diseases is terrible. Mexican lime witches' broom (MLWB) is a phytoplasma disease, which has caused considerable damage...  相似文献   
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The ability of pristine graphene (PG) and Al-doped graphene (AlG) to detect toxic acrolein (C3H4O) was investigated by using density functional calculations. It was found that C3H4O molecule can be adsorbed on the PG and AlG with adsorption energies about ?50.43 and – v30.92 kcal mol?1 corresponding to the most stable configurations, respectively. Despite the fact that interaction of C3H4O has no obvious effects on the of electronic properties of PG, the interaction between C3H4O and AlG can induce significant changes in the HOMO/LUMO energy gap of the sheet, altering its electrical conductivity which is beneficial to sensor designing. Thus, the AlG may be sensitive in the presence of C3H4O molecule and might be used in its sensor devices. Also, applying an external electric filed in an appropriate orientation (almost stronger than 0.01 a.u.) can energetically facilitate the adsorption of C3H4O molecule on the AlG.  相似文献   
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