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1.
The IR6 gene of equine herpesvirus 1 (EHV-1) is a novel gene that maps within each inverted repeat (IR), encodes a potential protein of 272 amino acids, and is expressed as a 1.2-kb RNA whose synthesis begins at very early times (1.5 h) after infection and continues throughout the infection cycle (C. A. Breeden, R. R. Yalamanchili, C.F. Colle, and D.J. O'Callaghan, Virology 191:649-660,1992). To identify the IR6 protein and ascertain its properties, we generated an IR6-specific polyclonal antiserum to a TrpE/IR6 fusion protein containing 129 amino acids (residues 134 to 262) of the IR6 protein. This antiserum immunoprecipitated a 33-kDa protein generated by in vitro translation of mRNA transcribed from a pGEM construct (IR6/pGEM-3Z) that contains the entire IR6 open reading frame. The anti-IR6 antibody also recognized an infected-cell protein of approximately 33 kDa that was expressed as early as 1 to 2 h postinfection and was synthesized throughout the infection cycle. A variety of biochemical analyses including radiolabeling the IR6 protein with oligosaccharide precursors, translation of IR6 mRNA in the presence of canine pancreatic microsomes, radiolabeling the IR6 protein in the presence of tunicamycin, and pulse-chase labeling experiments indicated that the two potential sites for N-linked glycosylation were not used and that the IR6 protein does not enter the secretory pathway. To address the possibility that the unique IR6 gene encodes a novel regulatory protein, we transiently transfected an IR6 expression construct into L-M fibroblasts alone or with an immediate-early gene expression construct along with a representative EHV-1 immediate-early, early, or late promoter-chloramphenicol acetyltransferase reporter construct. The results indicated that the IR6 protein does not affect the expression of these representative promoter constructs. Interestingly, the IR6 protein was shown to be phosphorylated and to associate with purified EHV-1 virions and nucleocapsids. Lastly, immunofluorescence and laser-scanning confocal microscopic analyses revealed that the IR6 protein is distributed throughout the cytoplasm at early times postinfection and that by 4 to 6 h it appears as "dash-shaped" structures that localize to the perinuclear region. At late times after infection (8 to 12 h), these structures assemble around the nucleus, and three-dimensional image analyses reveal that the IR6 protein forms a crown-like structure that surrounds the nucleus as a perinuclear network.  相似文献   
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In 1968-69 certain juvenile diabetics receiving NPH insulin began having pre-breakfast glucosuria and mid-morning hypoglycemic reactions. A mail survey of our clinic population and a study done at the Quebec camp for diabetic children in 1969 revealed that certain lot numbers were associated with poor control and that a change to new lot numbers or alternate insulin preparations resulted in better control. “Suspect” insulin preparations and non-suspect insulins were given to newly diagnosed diabetics, and plasma insulin and glucose levels were measured over a 24-hour period. The data confirmed that the “suspect” insulins were causing early hypoglycemia and failing to control hyperglycemia during the latter hours of the 24-hour period. The lower glucose levels were associated with higher plasma insulin levels. The “suspect” insulins were further found to have elevated levels of free insulin in the supernatant fluid.The requirements for quality control of modified insulin preparations are reviewed and suggestions are offered for their improvement.  相似文献   
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The quantitative analysis of vocal disorders by nonlinear signal processing methods has been extensively used in the last two decades. In this work, two algorithms for nonlinear time-series analysis, Sample Entropy and cross-Sample Entropy, are used on electroglottogram (EGG) and microphone (MIC) signals recorded from 51 normal and 80 dysphonic subjects, to obtain summary measures of voice disorders through SampEn and cross-SampEn indices. Such parameters quantify, respectively, the degree of irregularity (in the sense of self-dissimilarity) within a time-series and of asynchrony (in the sense of cross-dissimilarity) between two distinct time-series. The aims of this work are: to determine if statistically significant differences in terms of signal irregularity quantified by SampEn occur between normal and pathological subjects, investigating whether or not such differences can be equally seen in EGG and MIC; to assess if cross-SampEn reveals different degrees of asynchrony between EGG and MIC signals in the two groups. Results show that SampEn in pathological subjects is higher than in normal subjects for both EGG and MIC time-series, with a statistically significant difference detectable from both signals (Pe < 10?4 for EGG and Pe < 10?7 for MIC). Cross-SampEn exhibits a statistically significant difference too, showing a higher degree of cross-dissimilarity between EGG and MIC time-series for pathological subjects (Pe < 10?4). In conclusion, SampEn and cross-SampEn well quantify the increase of complexity of both EGG and MIC signals and the decrease of their cross-similarity in presence of vocal disorders. Thanks to the complementarity of nonlinear indicators to the traditionally considered linear ones, SampEn and cross-SampEn appear as suitable candidates to enter the pool of approaches to investigate speech pathologies and to obtain potentially new insights on their nature.  相似文献   
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Estimating the main axis of rotation (AoR) of a human joint represents an important issue in biomechanics. This study compared three formal methods used to estimate functional AoR, namely a cylindrical fitting method, a mean helical axis transformation, and a symmetrical axis approach. These methods were tested on 106 subjects undergoing navigated total knee arthroplasty. AoR orientation in 3D and in the frontal and coronal planes provided by each method was compared to the transepicondylar axis direction. Although all the methods resulted effective, significant differences were identified among them, relatively to the orientation in 3D and in the frontal plane projection. This was probably due to the presence of secondary rotations during the first degrees of knee flexion.  相似文献   
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Cl-36 is an important component of nuclear waste. The concentrations of stable chlorine (Cl) in pig and cow tissues were measured to provide information which can be used to parameterize models of 36Cl transfer into agricultural animals. The concentration of stable Cl in cows’ milk was 1.0 ± 0.2 g L−1, in cow muscle it was 0.7 ± 0.2 g kg−1 wet mass (wm) and in pig muscle 0.4 ± 0.1 g kg−1 wm. The concentration of stable Cl in cow and pig liver was 0.9 ± 0.3 g kg−1 wm, which was about two-fold higher than that in the kidney and lung. Due to homeostatic control, stable Cl concentrations in animal tissues are not related to the amount ingested daily in herbage at intake rates in the normal physiological range of up to 188 g day−1 for cows and up to 40 g day−1 for pigs. Therefore, the commonly used transfer coefficient is not suitable for use in quantifying the transfer of 36Cl to milk and meat. Since the metabolism of stable Cl and 36Cl in an animal’s body is identical, the average equilibrium ratios of 36Cl to stable Cl in the daily ration (36Cl (g kg−1)/Cl (g kg−1)) and animal tissues will be the same. We therefore conclude that the average equilibrium Cl isotopic ratio in the dietary daily intake should be used to predict the contamination of meat and milk with 36Cl.  相似文献   
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Male Long Evans rats were reared from weaning (21–23 days) either in isolation or in groups of four for 40 days. Animals were then individually introduced to a testing apparatus consisting of two distinct chambers. A modified place preference paradigm was used consisting of 3 phases: (1) An habituation phase (4 days) during which rats were allowed free access to the entire test apparatus for 15 min. periods daily; (2) A conditioning phase (4 days) during which rats were confined to their non-preferred side for 15 minutes each day immediately following subcutaneous injection of 0, 20, 40 and 80 μg/kg of heroin HCl; (3) A test phase (1 day) during which rats were again allowed free access to the testing chamber following injection of vehicle. The difference in time spent on the conditioned side during habituation and test periods was determined. The group-reared rats showed similar effects for all doses of heroin whereas the same magnitude of drug effect was attained only at the highest dose used in the isolated rats. This differential sensitivity to heroin in the place preference paradigm is discussed in terms of the modification of behavioral effects of opiates by environmental influences.  相似文献   
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Hydrolytic deamination of cytosine to uracil in DNA is increased in organisms adapted to high temperatures. Hitherto, the uracil base excision repair (BER) pathway has only been described in two archaeons, the crenarchaeon Pyrobaculum aerophilum and the euryarchaeon Archaeoglobus fulgidus, which are hyperthermophiles and use single-nucleotide replacement. In the former the apurinic/apyrimidinic (AP) site intermediate is removed by the sequential action of a 5'-acting AP endonuclease and a 5'-deoxyribose phosphate lyase, whereas in the latter the AP site is primarily removed by a 3'-acting AP lyase, followed by a 3'-phosphodiesterase. We describe here uracil BER by a cell extract of the thermoacidophilic euryarchaeon Thermoplasma acidophilum, which prefers a similar short-patch repair mode as A. fulgidus. Importantly, T. acidophilumcell extract also efficiently executes ATP/ADP-stimulated long-patch BER in the presence of deoxynucleoside triphosphates, with a repair track of ~15 nucleotides. Supplementation of recombinant uracil-DNA glycosylase (rTaUDG; ORF Ta0477) increased the formation of short-patch at the expense of long-patch repair intermediates, and additional supplementation of recombinant DNA ligase (rTalig; Ta1148) greatly enhanced repair product formation. TaUDG seems to recruit AP-incising and -excising functions to prepare for rapid single-nucleotide insertion and ligation, thus excluding slower and energy-costly long-patch BER.  相似文献   
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