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51.
The purpose of this study was to investigate the effect of chronic feline immunodeficiency virus (FIV) infection, and efficacy of marbofloxacin treatment, on 'Candidatus Mycoplasma haemominutum' infection. Six cats chronically infected with FIV-Glasgow8 (group A) and six FIV-free cats (group B) were infected with 'Candidatus M. haemominutum' on day 0 by intravenous inoculation of blood. From day 0 to 105 post-infection (pi), blood samples were collected for 'Candidatus M. haemominutum' and FIV provirus quantitative real-time polymerase chain reaction (PCR) and haematological examination. Three of the six cats in each of the groups were randomly selected to receive marbofloxacin treatment (2mg/kg PO SID) from day 49 to day 76 pi, with the remaining cats being untreated controls. Maximum 'Candidatus M. haemominutum' copy number was reached around day 30 pi. No overt cycling or marked variation in copy number was observed. No significant effect of FIV infection on 'Candidatus M. haemominutum' copy number kinetics or anaemia indices was found. No correlation was found between FIV provirus copy number and 'Candidatus M. haemominutum' copy number or haematological variables. Although marbofloxacin treatment was associated with a significant decrease in 'Candidatus M. haemominutum' copy number, the copy number plateaued during treatment, with no negative PCR results. Additionally, after termination of marbofloxacin treatment the copy numbers of the treated cats increased to reach levels similar to those of the untreated cats within 7-10 days. This study documents, for the first time, the infection kinetics and antibiotic responsiveness of 'Candidatus M. haemominutum' infection.  相似文献   
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AIMS: To investigate whether Arcobacter spp. colonize the poultry-rearing environment or whether they are contaminants acquired during transportation and/or from the processing plant. METHODS AND RESULTS: Samples were collected on poultry farms and in the processing plant during slaughter and dressing. Two cultural methods of detection were used. Isolates were identified to species level using a multiplex-polymerase chain reaction (m-PCR) method, either on the initial suspensions, or after enrichment, or on pure cultures of isolates. Of the 62 samples examined from poultry farms, arcobacters were found only outside the rearing sheds (in effluent sludge and stagnant water). Thirty-four samples were examined from the processing plant and 26 were positive for arcobacters. All the isolates were Arcobacter butzleri. Arcobacters were not found in any sample by direct plating nor by m-PCR on the initial suspensions, thus it was concluded that numbers were very low. CONCLUSIONS: Arcobacter spp. were not found in samples from the live birds and their immediate environment, but A. butzleri was found in effluent sludge and stagnant water outside the rearing sheds. However, A. butzleri is common in poultry abattoirs, and it appears that poultry carcasses are contaminated during processing. SIGNIFICANCE AND IMPACT OF THE STUDY: Arcobacters are not found inside poultry-rearing sheds, but are contaminants in the processing environment.  相似文献   
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Java language has been demonstrated to be an effective tool in supporting medical image viewing in Russia. This evaluation was completed by obtaining a maximum of 20 images, depending on the client's computer workstation from one patient using a commercially available computer tomography (CT) scanner. The images were compared against standard CT images that were viewed at the site of capture. There was no appreciable difference. The client side is a lightweight component that provides an intuitive interface for end users. Each image is loaded in its own thread and the user can begin work after the first image has been loaded. This feature is especially useful on slow connection speed, 9.6 Kbps for example. The server side, which is implemented by the Java Servlet Engine works more effective than common gateway interface (CGI) programs do. Advantages of the Java Technology place this program on the next level of application development. This paper presents a unique application of Java in telemedicine.  相似文献   
54.
The gene bifocal (bif), required for photoreceptor morphogenesis in the Drosophila compound eye, encodes a protein that is shown to interact with protein phosphatase 1 (PP1) using the yeast two-hybrid system. Complex formation between Bif and PP1 is supported by coprecipitation of the two proteins. Residues 992 to 995 (RVQF) in the carboxy-terminal region of Bif, which conform to the consensus PP1-binding motif, are shown to be essential for the interaction of Bif with PP1. The interaction of PP1 with bacterially expressed and endogenous Bif can be disrupted by a synthetic peptide known to block interaction of other regulatory subunits with PP1. Null bif mutants exhibit a rough eye phenotype, disorganized rhabdomeres (light-gathering rhodopsin-rich microvillar membrane structures in the photoreceptor cells) and alterations in the actin cytoskeleton. Expression of wild-type bif transgenes resulted in significant rescue of these abnormalities. In contrast, expression of transgenes encoding the Bif F995A mutant, which disrupts binding to PP1, was unable to rescue any aspect of the bif phenotype. The results indicate that the PP1-Bif interaction is critical for the rescue and that a major function of Bif is to target PP1c to a specific subcellular location. The role of the PP1-Bif complex in modulating the organization of the actin cytoskeleton underlying the rhabdomeres is discussed.  相似文献   
55.
Nitric oxide has been strongly implicated in the development of tissue infarction in response to focal cerebral ischemia. Nitric oxide and its derivatives can inhibit components of the electron transport chain, providing a likely target for these substances in ischemic and post-ischemic brain. Lactate content is increased during post-ischemic reperfusion in tissue destined to become infarcted, consistent with impairment of mitochondrial respiration. To investigate the possible involvement of nitric oxide in generating these changes, we have tested the effect of 7-nitroindazole, a nitric oxide synthase (NOS) inhibitor, on the content of lactate and other metabolites during early reperfusion following temporary focal ischemia. This treatment inhibited total NOS by approximately 50%. However, the treatment did not significantly affect the marked increases in lactate in post-ischemic brain nor did it alter the recovery of other energy-related metabolites. These findings indicate that inhibition of oxidative metabolism is probably not the primary site of the deleterious effects of nitric oxide and derivatives during early post-ischemic reperfusion. Special issue dedicated to John P. Blass.  相似文献   
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This study aimed to compare the effects of different velocities of eccentric muscle actions on acute blood lactate and serum growth hormone (GH) concentrations following free weight bench press exercises performed by resistance-trained men. Sixteen healthy men were divided into two groups: slow eccentric velocity (SEV; n = 8) and fast eccentric velocity (FEV; n = 8). Both groups performed four sets of eight eccentric repetitions at an intensity of 70% of their one repetition maximum eccentric (1RMecc) test, with 2-minute rest intervals between sets. The eccentric velocity was controlled to 3 seconds per range of motion for SEV and 0.5 seconds for the FEV group. There was a significant difference (P < 0.001) in the kinetics of blood lactate removal (at 3, 6, 9, 15, and 20 min) and higher mean values for peak blood lactate (P = 0.001) for the SEV group (9.1 ± 0.5 mM) compared to the FEV group (6.1 ± 0.4 mM). Additionally, serum GH concentrations were significantly higher (P < 0.001) at 15 minutes after bench press exercise in the SEV group (1.7 ± 0.6 ng · mL−1) relative to the FEV group (0.1 ± 0.0 ng · mL−1). In conclusion, the velocity of eccentric muscle action influences acute responses following bench press exercises performed by resistance-trained men using a slow velocity resulting in a greater metabolic stress and hormone response.  相似文献   
58.

Background

Chromosome four of Drosophila melanogaster, known as the dot chromosome, is largely heterochromatic, as shown by immunofluorescent staining with antibodies to heterochromatin protein 1 (HP1) and histone H3K9me. In contrast, the absence of HP1 and H3K9me from the dot chromosome in D. virilis suggests that this region is euchromatic. D. virilis diverged from D. melanogaster 40 to 60 million years ago.

Results

Here we describe finished sequencing and analysis of 11 fosmids hybridizing to the dot chromosome of D. virilis (372,650 base-pairs) and seven fosmids from major euchromatic chromosome arms (273,110 base-pairs). Most genes from the dot chromosome of D. melanogaster remain on the dot chromosome in D. virilis, but many inversions have occurred. The dot chromosomes of both species are similar to the major chromosome arms in gene density and coding density, but the dot chromosome genes of both species have larger introns. The D. virilis dot chromosome fosmids have a high repeat density (22.8%), similar to homologous regions of D. melanogaster (26.5%). There are, however, major differences in the representation of repetitive elements. Remnants of DNA transposons make up only 6.3% of the D. virilis dot chromosome fosmids, but 18.4% of the homologous regions from D. melanogaster; DINE-1 and 1360 elements are particularly enriched in D. melanogaster. Euchromatic domains on the major chromosomes in both species have very few DNA transposons (less than 0.4 %).

Conclusion

Combining these results with recent findings about RNAi, we suggest that specific repetitive elements, as well as density, play a role in determining higher-order chromatin packaging.  相似文献   
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