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91.
Types and the number of stomata in the following Arum species: Arum italicum Mill., Arum maculatum var. maculatum L. and Arum maculatum var. immaculatum L., Arum alpinum var. pannonicum Terpo. and Arum alpinum var. intermedium Schur. in three different locations in Zablaće, Normanci and Bilje were investigated. The most prevalent stomata type at both upper and lower epidermis for each Arum species was mostly stomata type paracytic, followed by hexacytic, tetracytic or brachyparacytic as far as locality is concerned. Helicocytic type was more prevalent in Arum alpinum var. pannonicum Terpo. and Arum alpinum var. intermedium Schur. at Bilje. Other stomata types were very rare. A striking regularity in the occurrence of stomata types was not found within a single species. Some stomata types, however, were found either at adaxial or abaxial epidermis or were not present at all. The number of stomata per square mm varied from 25 to 651. A statistically significant difference in the number of stomata per square mm at upper and lower epidermis among Arum species was determined in locations Zablaće and Normanci, whereas no statistically significant differences were found in location Bilje.  相似文献   
92.

Mitochondrial dysfunction plays crucial role in the pathologenesis of myocardial infarction (MI). The present study evaluated the protective effect of α-bisabolol against isoproterenol (ISO)-induced mitochondrial dysfunction and apoptosis in rats. Male albino Wistar rats were pre- and co-treated with intraperitoneal injection of α-bisabolol (25 mg/kg body weight) daily for 10 days. To induce experimental MI, ISO (85 mg/kg body weight) was injected subcutaneously to the rats at an interval of 24 h for 2 days (9th and 10th day). ISO-induced MI was indicated by the decreased activities of heart creatine kinase and lactate dehydrogenase in rats. ISO administration also enhanced the concentrations of heart mitochondrial lipid peroxidation products and decreased the activities/concentrations of mitochondrial antioxidants, Kreb’s cycle dehydrogenases and mitochondrial electron transport chain complexes I, II?+?III and IV in rats. Furthermore, ISO triggers calcium overload and ATP depletion in the rat’s heart mitochondria followed by the mitochondrial cytochrome-C release and the activation of intrinsic pathway of apoptosis by upregulating the myocardial pro-apoptotic Bax, P53, APAF-1, active caspase-3, active caspase-9 and down regulating the expressions of anti-apoptotic Bcl-2. α-Bisabolol pre and co-treatment showed considerable protective effects on all the biochemical and molecular parameters studied. Transmission electron microscopic study and mitochondrial swelling assay confirmed our biochemical and molecular findings. The in vitro study on hydroxyl radical also revealed the potent free radical scavenging activity of α-bisabolol. Thus, α-bisabolol attenuates mitochondrial dysfunction and intrinsic pathway of apoptosis in ISO-induced myocardial infarcted rats.

  相似文献   
93.
Residual dipolar couplings (RDCs) are NMR parameters that provide both structural and dynamic information concerning inter-nuclear vectors, such as N–HN and Cα–Hα bonds within the protein backbone. Two approaches for extracting this information from RDCs are the model free analysis (MFA) (Meiler et al. in J Am Chem Soc 123:6098–6107, 2001; Peti et al. in J Am Chem Soc 124:5822–5833, 2002) and the direct interpretation of dipolar couplings (DIDCs) (Tolman in J Am Chem Soc 124:12020–12030, 2002). Both methods have been incorporated into iterative schemes, namely the self-consistent RDC based MFA (SCRM) (Lakomek et al. in J Biomol NMR 41:139–155, 2008) and iterative DIDC (Yao et al. in J Phys Chem B 112:6045–6056, 2008), with the goal of removing the influence of structural noise in the MFA and DIDC formulations. Here, we report a new iterative procedure entitled Optimized RDC-based Iterative and Unified Model-free analysis (ORIUM). ORIUM unifies theoretical concepts developed in the MFA, SCRM, and DIDC methods to construct a computationally less demanding approach to determine these structural and dynamic parameters. In all schemes, dynamic averaging reduces the actual magnitude of the alignment tensors complicating the determination of the absolute values for the generalized order parameters. To readdress this scaling issue that has been previously investigated (Lakomek et al. in J Biomol NMR 41:139–155, 2008; Salmon et al. in Angew Chem Int Edit 48:4154–4157, 2009), a new method is presented using only RDC data to establish a lower bound on protein motion, bypassing the requirement of Lipari–Szabo order parameters. ORIUM and the new scaling procedure are applied to the proteins ubiquitin and the third immunoglobulin domain of protein G (GB3). Our results indicate good agreement with the SCRM and iterative DIDC approaches and signify the general applicability of ORIUM and the proposed scaling for the extraction of inter-nuclear vector structural and dynamic content.  相似文献   
94.
Inhibitors of the MAP kinase p38 provide a novel approach for the treatment of osteoporosis, inflammatory disorders, and cancer. We have identified N-(3-tert-butyl-1-methyl-5-pyrazolyl)-N'-(4-(4-pyridinylmethyl)phenyl)urea as a potent and selective p38 kinase inhibitor in biochemical and cellular assays. This compound is orally active in two acute models of cytokine release (TNF-induced IL-6 and LPS-induced TNF) and a chronic model of arthritis (20-day murine collagen-induced arthritis).  相似文献   
95.
Several new R(2)eddp (R = i-Pr, i-Bu; eddp = ethylenediamine-N,N'-di-3-propionate) esters and corresponding platinum(ii) and platinum(iv) complexes of the general formula [PtCl(n)(R(2)edda-type)] (n = 2, 4) were synthesized and characterized by spectroscopic methods (IR, (1)H and (13)C NMR) and elemental analysis. The crystal structure of platinum(iv) complex [PtCl(4){(c-Pe)(2)eddip}] () was resolved and is given herein. Ligand precursors, platinum(ii), and platinum(iv) complexes were tested against eight tumor cell lines (CT26CL25, HTC116, SW620, PC3, LNCaP, U251, A375, and B16). Selectivity in the action of those compounds between tumor and two normal primary cells (fibroblasts and keratinocytes) are discussed. A structure-activity relationship of these compounds is discussed. Furthermore, cell cycle distribution, induction of necrosis, apoptosis, autophagy, anoikis, caspase activation, ROS, and RNS are presented on the cisplatin-resistant colon carcinoma HCT116 cell line.  相似文献   
96.
Nucleotide sequence heterogeneity of an RNA phage population   总被引:45,自引:0,他引:45  
E Domingo  D Sabo  T Taniguchi  C Weissmann 《Cell》1978,13(4):735-744
The nucleotide sequence of 32P-RNA from Q beta phage clones was sampled by two-dimensional polyacrylamide gel electrophoresis of the RNAase T1-resistant oligonucleotides (T1 fingerprinting). About 15% of the clones derived from a multiply passaged Q beta population showed fingerprint patterns which deviated from that of the RNA from the total population. All deviations examined could be attributed to one and, less frequently, to two or more nucleotide transitions. Since the fingerprinting technique allows the analysis of only about 10% of the RNA sequence, we estimate that each viable phage genome in a multiply passaged population differs in one to two positions from the "average" sequence of the parental population. Several deviant clones were tested by growth competition against a "wildtype" population, after 10-20 generations, the resulting phage showed the "wild-type" T1 fingerprint pattern. We propose that a Q beta phage population is in a dynamic equilibrium, with viable mutants arising at a high rate (Batschelet, Domingo and Weissmann, 1976; Domingo, Flavell and Weissmann, 1976) on the one hand, and being strongly selected against on the other. The genome of Q beta phage cannot be described as a defined unique structure, but rather as a weighted average of a large number of different individual sequences.  相似文献   
97.
A young Griffon vulture died with signs of convulsion, vomiting, tremor, seizures propulsions and lack of co-ordination. Toxicological analysis of the stomach content revealed the presence of methomyl (9.3 mg/kg), methomyloxime (6.7 mg/kg) and deltamethrin (6.1 mg/kg). Concentrations of methomyl and its intermediate methomyloxime, combined with results of other analysis, indicate methomyl as the cause of death of this bird.  相似文献   
98.
Our molecular phylogenetic analyses shed some light on the evolutionary relationships within the Hamelieae tribe. Phylogenetic reconstructions based on Internal Transcribed Spacer and trnL-F sequence data revealed the presence of three distinct evolutionary lineages. The first clade includes Hamelia and Syringantha, the second clade includes Deppea s.l. (including Bellizinca, Csapodya, and Edithea), and the third clade includes Pinarophyllon, Deppeopsis, Hoffmannia,Pseudomiltemia, Plocaniophyllon, Omiltemia, and Renistipula. The phylogenetic analysis re-evaluated some taxonomical combinations. The transfer of Deppeopsistaxa from Deppea s.l. is supported, but however, the monophyly of the genus is not. The transfer of Renistipula from Rondeletieae is also highly supported. BothCsapodya and Edithea species form a well-defined group among Deppea s.l. with high posterior probabilities, allowing to reconsider the exclusion or integration of these taxa to Deppea.  相似文献   
99.
The generality and spectrum of chromatin-remodeling requirements for nuclear receptor function are unknown. We have characterized glucocorticoid receptor (GR) binding events and chromatin structural transitions across GR-induced or -repressed genes. This analysis reveals that GR binding invariably occurs at nuclease-accessible sites (DHS). A remarkable diversity of mechanisms, however, render these sites available for GR binding. Accessibility of the GR binding sites is either constitutive or hormone inducible. Within each category, some DHS sites require the Brg1-containing Swi/Snf complex, but others are Brg1 independent, implicating a different remodeling complex. The H2A.Z histone variant is highly enriched at both inducible and constitutive DHS sites and is subject to exchange during hormone activation. The DHS profile is highly cell specific, implicating cell-selective organization of the chromatin landscape as a critical determinant of tissue-selective receptor function. Furthermore, the widespread requirement for chromatin remodeling supports the recent hypothesis that the rapid exchange of receptor proteins occurs during nucleosome reorganization.  相似文献   
100.
Human knowledge curators are intrinsically better than their digital counterparts at providing relevant answers to queries. That is mainly due to the fact that an experienced biological brain will account for relevant community expertise as well as exploit the underlying connections between knowledge pieces when offering suggestions pertinent to a specific question, whereas most automated database managers will not. We address this problem by proposing an architecture for the autonomic curation of crowdsourced knowledge, that is underpinned by semantic technologies. The architecture is instantiated in the career data domain, thus yielding Aviator, a collaborative platform capable of producing complete, intuitive and relevant answers to career related queries, in a time effective manner. In addition to providing numeric and use case based evidence to support these research claims, this extended work also contains a detailed architectural analysis of Aviator to outline its suitability for automatically curating knowledge to a high standard of quality.  相似文献   
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