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991.
Quesada P Tramontano F Faraone-Mennella MR Farina B 《Molecular and cellular biochemistry》2000,210(1-2):91-99
The poly(ADP-ribosyl)ation system, associated with different nuclear fractions of rat testis, has been analyzed for both pADPR and pADPR acceptor proteins. The DNase I sensitive and resistant chromatin contain 35% and 40%, respectively, of the total pADPR synthesized in intact nuclei incubated with [32P]NAD. Moreover, the residual 25% were estimated to be associated with the nuclear matrix.Three different classes of pADPR are present in the nuclei. The longest and branched ADPribose polymers modify proteins present in the DNase I resistant (2 M NaCl extractable) chromatin and in the nuclear matrix, whereas polymers of > 20 residues interact with the components of the DNase I sensitive chromatin and oligomers of 6 ADPribose residues are bound specifically to the acid-soluble chromosomal proteins, present in isolated nuclear matrix. The main pADPR acceptor protein in all the nuclear fractions is represented by the PARP itself (auto-modification reaction). The hetero-modification reaction occurs mostly on histone H1 and core histones, that have been found associated to DNase I sensitive and resistant chromatin, respectively. Moreover, an oligo(ADP-ribosyl)ation occurs on core histones tightly-bound to the matrix associated regions (MARs) of chromatin loops. 相似文献
992.
Piletz JE Ivanov TR Sharp JD Ernsberger P Chang CH Pickard RT Gold G Roth B Zhu H Jones JC Baldwin J Reis DJ 《DNA and cell biology》2000,19(6):319-329
The imidazoline-1 receptor (IR1) is considered a novel target for drug discovery. Toward cloning an IR1, a truncated cDNA clone was isolated from a human hippocampal lambda gt11 cDNA expression library by relying on the selectivity of two antisera directed against candidate IR proteins. Amplification reactions were performed to extend the 5' and 3' ends of this cDNA, followed by end-to-end PCR and conventional cloning. The resultant 5131-basepair molecule, designated imidazoline receptor-antisera-selected (IRAS) cDNA, was shown to encode a 1504-amino acid protein (IRAS-1). No relation exists between the amino acid sequence of IRAS-1 and proteins known to bind imidazolines (e.g., it is not an alpha2-adrenoceptor or monoamine oxidase subtype). However, certain sequences within IRAS-1 are consistent with signaling motifs found in cytokine receptors, as previously suggested for an IR1. An acidic region in IRAS-1 having an amino acid sequence nearly identical to that of ryanodine receptors led to the demonstration that ruthenium red, a dye that binds the acidic region in ryanodine receptors, also stained IRAS-1 as a 167-kD band on SDS gels and inhibited radioligand binding of native I1 sites in untransfected PC-12 cells (a source of authentic I1 binding sites). Two epitope-selective antisera were also generated against IRAS-1, and both reacted with the same 167-kD band on Western blots. In a host-cell-specific manner, transfection of IRAS cDNA into Chinese hamster ovary cells led to high-affinity I1 binding sites by criteria of nanomolar affinity for moxonidine and rilmenidine. Thus, IRAS-1 is the first protein discovered with characteristics of an IR1. 相似文献
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995.
The main objective of this study was to evaluate the efficacy of a biocide and a corrosion inhibitor against the corrosion of a circulating pipe in a cooling tower. Isothiazolone was tested as the industrial biocide. The results showed that the biocide by itself or combined with a dispersant was not efficient to control corrosion in the industrial system. Corrosion rates of 0.324 mm/year were recorded in both the presence and absence of the biocide. Corrosion control was successfully accomplished by using a corrosion inhibitor. In the latter case the maximum corrosion rate of 0.024 mm/year were obtained. 相似文献
996.
According to a popular hypothesis, short-term memories are stored as persistent neural activity maintained by synaptic feedback loops. This hypothesis has been formulated mathematically in a number of recurrent network models. Here we study an abstraction of these models, a single neuron with a synapse onto itself, or autapse. This abstraction cannot simulate the way in which persistent activity patterns are distributed over neural populations in the brain. However, with proper tuning of parameters, it does reproduce the continuously graded, or analog, nature of many examples of persistent activity. The conditions for tuning are derived for the dynamics of a conductance-based model neuron with a slow excitatory autapse. The derivation uses the method of averaging to approximate the spiking model with a nonspiking, reduced model. Short-term analog memory storage is possible if the reduced model is approximately linear and if its feedforward bias and autapse strength are precisely tuned. 相似文献
997.
Worthley SG Roque M Helft G Soundararajan K Siddiqui M Reis ED 《Laboratory animals》2000,34(2):199-201
The orotracheal intubation of rabbits is complicated by their oropharyngeal anatomy. Numerous techniques to intubate rabbits have been described; however, these methods require specialized devices, tracheostomy, or are performed in a blind fashion. We describe a technique for the intubation of the rabbit under direct visualization with a standard, small-bore, fibre-optic laparoscope, which is both rapid and simple to perform. 相似文献
998.
Steinberg Raphael S. Silva Lilian C. Silva e de Souza Marcelo R. Reis Ronaldo B. Bicalho Adriano F. Nunes Joo P. S. Dias Adriana A. M. Nicoli Jacques R. Neumann Elisabeth Nunes lvaro C. 《International microbiology》2022,25(1):189-206
International Microbiology - Mastitis is one of the most important causes of loss of cattle production, burdening producers due to the increased cost of milk production and decreased herd... 相似文献
999.
Reis Bruna Paolinelli Szitár Katalin Kövendi-Jakó Anna Török Katalin Sáradi Nóra Csákvári Edina Halassy Melinda 《Landscape and Ecological Engineering》2022,18(4):429-440
Landscape and Ecological Engineering - To help upscale ecological restoration of degraded lands, landscape factors and longer time scales should be considered when assessing restoration efforts. We... 相似文献
1000.
Eric Cornes Montserrat Porta-De-La-Riva David Aristizábal-Corrales Ana María Brokate-Llanos Francisco Javier García-Rodríguez Iris Ertl Mònica Díaz Laura Fontrodona Kadri Reis Robert Johnsen David Baillie Manuel J. Mu?oz Mihail Sarov Denis Dupuy Julián Cerón 《RNA (New York, N.Y.)》2015,21(9):1544-1553