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排序方式: 共有333条查询结果,搜索用时 718 毫秒
91.
Chetboul V Tran D Carlos C Tessier D Pouchelon JL 《Schweizer Archiv für Tierheilkunde》2004,146(6):265-275
A retrospective study was done on 14 cats and 36 dogs diagnosed with right atrioventricular valve malformations (RAVM), either tricuspid dysplasia (n = 38) or Ebstein's anomaly (n = 12). Comparison with a large reference population including 85 250 animals allowed an epidemiologic analysis of these RAVM, demonstrating that Labrador, Boxer and Chartreux cats had a 35, 7 and 11-fold higher risk respectively to be affected by one of these heart diseases than other breeds, without sexual predisposition. In 93% of cases, cardiac auscultation revealed a heart murmur, whose grade was not significantly correlated with the echographic stages of the valvular disease. The echocardiographic examination confirmed the frequent association between RAVM and other congenital anomalies, particularly mitral dysplasia, in 84% and 20% of tricuspid dysplasia and Ebstein anomaly respectively. Last, the prognosis of RAVM was worsened by atrial fibrillation and right-sided heart failure. 相似文献
92.
93.
Methé BA Nelson KE Eisen JA Paulsen IT Nelson W Heidelberg JF Wu D Wu M Ward N Beanan MJ Dodson RJ Madupu R Brinkac LM Daugherty SC DeBoy RT Durkin AS Gwinn M Kolonay JF Sullivan SA Haft DH Selengut J Davidsen TM Zafar N White O Tran B Romero C Forberger HA Weidman J Khouri H Feldblyum TV Utterback TR Van Aken SE Lovley DR Fraser CM 《Science (New York, N.Y.)》2003,302(5652):1967-1969
The complete genome sequence of Geobacter sulfurreducens, a delta-proteobacterium, reveals unsuspected capabilities, including evidence of aerobic metabolism, one-carbon and complex carbon metabolism, motility, and chemotactic behavior. These characteristics, coupled with the possession of many two-component sensors and many c-type cytochromes, reveal an ability to create alternative, redundant, electron transport networks and offer insights into the process of metal ion reduction in subsurface environments. As well as playing roles in the global cycling of metals and carbon, this organism clearly has the potential for use in bioremediation of radioactive metals and in the generation of electricity. 相似文献
94.
Paulsen IT Banerjei L Myers GS Nelson KE Seshadri R Read TD Fouts DE Eisen JA Gill SR Heidelberg JF Tettelin H Dodson RJ Umayam L Brinkac L Beanan M Daugherty S DeBoy RT Durkin S Kolonay J Madupu R Nelson W Vamathevan J Tran B Upton J Hansen T Shetty J Khouri H Utterback T Radune D Ketchum KA Dougherty BA Fraser CM 《Science (New York, N.Y.)》2003,299(5615):2071-2074
The complete genome sequence of Enterococcus faecalis V583, a vancomycin-resistant clinical isolate, revealed that more than a quarter of the genome consists of probable mobile or foreign DNA. One of the predicted mobile elements is a previously unknown vanB vancomycin-resistance conjugative transposon. Three plasmids were identified, including two pheromone-sensing conjugative plasmids, one encoding a previously undescribed pheromone inhibitor. The apparent propensity for the incorporation of mobile elements probably contributed to the rapid acquisition and dissemination of drug resistance in the enterococci. 相似文献
95.
The Toll-like receptor 2 pathway establishes colonization by a commensal of the human microbiota 总被引:4,自引:0,他引:4
Round JL Lee SM Li J Tran G Jabri B Chatila TA Mazmanian SK 《Science (New York, N.Y.)》2011,332(6032):974-977
Mucosal surfaces constantly encounter microbes. Toll-like receptors (TLRs) mediate recognition of microbial patterns to eliminate pathogens. By contrast, we demonstrate that the prominent gut commensal Bacteroides fragilis activates the TLR pathway to establish host-microbial symbiosis. TLR2 on CD4(+) T cells is required for B. fragilis colonization of a unique mucosal niche in mice during homeostasis. A symbiosis factor (PSA, polysaccharide A) of B. fragilis signals through TLR2 directly on Foxp3(+) regulatory T cells to promote immunologic tolerance. B. fragilis lacking PSA is unable to restrain T helper 17 cell responses and is defective in niche-specific mucosal colonization. Therefore, commensal bacteria exploit the TLR pathway to actively suppress immunity. We propose that the immune system can discriminate between pathogens and the microbiota through recognition of symbiotic bacterial molecules in a process that engenders commensal colonization. 相似文献
96.
Son Hai VU Bomin KIM Alisha Wehdnesday Bernardo REYES Tran Xuan Ngoc HUY John Hwa LEE Suk KIM Hyun-Jin KIM 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(3):482
To better understanding Brucella abortus infection, serum metabolites of B. abortus-infected and -uninfected mice were analyzed and twenty-one metabolites were tentatively identified at 3 and 14 days post-infection (d.p.i.). Level of most lysophosphatidylcholines (LPCs) was found to increase in infected mice at 3 d.p.i., while it was decreased at 14 d.p.i. as compared to uninfected mice. In contrast, acylcarnitines were initially reduced at 3 d.p.i then elevated after two-weeks of infection, while hydroxysanthine was increased at 14 d.p.i. in infected mice. Our findings suggest that the significant changes in LPCs and other identified metabolites may serve as potential biomarkers in acute phase of B. abortus infection. 相似文献
97.
Shuichi Fukuoka Tran Danh Suu Kaworu Ebana Luu Ngoc Trinh Tsukasa Nagamine Kazutoshi Okuno 《Genetic Resources and Crop Evolution》2006,53(4):753-761
Phenotypic variation of agronomic characters in aromatic rice (Oryza sativa L.) was analyzed in order to elucidate the genetic diversity of the populations of rice landraces. Thirteen populations in
Namdinh province, in the Red River Delta of Vietnam, were studied in both of farmers fields and an experimental field. Only
small differences were found in agronomic characters among the populations, including populations containing different varieties.
Variations among the populations in the frequency distributions of several characters suggested different degrees of diversity
among the populations even among populations with the same variety name. The phenotypic profiles of farmers fields were different
from those in an experimental field suggesting the environmental differences between them. One variety cultivated in the Myloc
district had different phenotypic characters from the other varieties in the Haihau district more clearly in the experimental
field. Since the small phenotypic variation in each of farm might be due to the genetic drift and selection by the farmers,
on farm conservation of the landraces of rice is considered to be under a force to decrease phenotypic diversity. The present
study suggests that the targeting several farms with different phenotypic profiles contribute to the conservation of regional
genetic diversity of the landraces of rice. 相似文献
98.
Ly-Nguyen B Van Loey AM Smout C Verlent I Duvetter T Hendrickx ME 《Journal of agricultural and food chemistry》2004,52(26):8144-8150
A proteinaceous pectin methylesterase inhibitor (PMEI) was isolated from kiwi fruit (Actinidia chinensiscv. Hayward) and purified by affinity chromatography on a cyanogen bromide (CNBr) Sepharose 4B-orange PME column. The optimal pH of banana PME activity was 7.0, whereas that for carrot and strawberry PME activity was 9.0. The optimal pH for the binding between kiwi fruit PMEI and these PMEs was 7.0. The kiwi fruit PMEI has a different affinity for PME depending on the plant source. The inhibition kinetics of kiwi fruit PMEI to banana and strawberry PME followed a noncompetitive type, whereas that to carrot PME followed a competitive type. The kiwi fruit PMEI was mixed with banana, carrot, and strawberry PME to obtain PMEI-PME complexes, which were then subjected to thermal (40-80 degrees C, atmospheric pressure) or high-pressure (10 degrees C, 100-600 MPa) treatment. Experimental data showed that the PMEI-PME complexes were easily dissociated by both thermal and high-pressure treatments. 相似文献
99.
H. I. Schiff G. I. Mackay C. Castledine G. W. Harris Q. Tran 《Water, air, and soil pollution》1986,30(1-2):105-114
A highly sensitive, lightweight, portable instrument has been developed for continuous monitoring of N02 in air. It operates by detecting the chemiluminescence produced when N02 encounters a surface wetted with a specially formulated solution containing luminol. Unlike other chemiluminescent instruments it measures N02 directly and does not require prior conversion of N02 to NO. It does not respond to H202, NO, HNO3, NH3, CO, C02, S02 or organic nitrates. The only interferences encountered to date are from 03 and PAN with the response to 03 being less than 0.2% of its response to N02. The response time of the instrument is less than 1 s and its sensitivity is better than 5 pptv. The instrument shows a negative temperature dependence of about 2% °C?1 which is compensated electronically. Measurements have been made with the instrument during a number of field missions in polluted urban and relatively clean rural air. The relative influences of photochemistry and transport from local sources has been observed. Simultaneous measurements made with this instrument and the unequivocal tunable diode laser absorption spectroscopy method have shown excellent agreement. 相似文献
100.
Ly-Nguyen B Van Loey AM Fachin D Verlent I Indrawati I Hendrickx ME 《Journal of agricultural and food chemistry》2002,50(19):5437-5444
Pectin methylesterase (PME) from carrots (Daucus carrota L.) was extracted and purified by affinity chromatography on a CNBr-Sepharose 4B-PME inhibitor column. A single protein and PME activity peak was obtained. A biochemical characterization in terms of molar mass (MM), isoelectric points (pI), and kinetic parameters of carrot PME was performed. In a second step, the thermal and high-pressure stability of the enzyme was studied. Isothermal and combined isothermal-isobaric inactivation of purified carrot PME could be described by a fractional-conversion model. 相似文献