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Dezfulian H Batisson I Fairbrother JM Lau PC Nassar A Szatmari G Harel J 《Journal of clinical microbiology》2003,41(4):1375-1385
The virulence genotype profile and presence of a pathogenicity island(s) (PAI) were studied in 18 strains of F165-positive Escherichia coli originally isolated from diseased calves or piglets. On the basis of their adhesion phenotypes and genotypes, these extraintestinal pathogenic strains were classified into three groups. The F165 fimbrial complex consists of at least two serologically and genetically distinct fimbriae: F165(1) and F165(2). F165(1) is encoded by the foo operon (pap-like), and F165(2) is encoded by fot (sfa related). Strains in group 1 were foo and fot positive, strains in group 2 were foo and afa positive, and strains in group 3 were foo positive only. The strains were tested for the presence of virulence genes found mainly in extraintestinal pathogenic E. coli (ExPEC) strains. Although all the strains were positive for the papA variant encoding F11 fimbriae incD, traT, and papC, the prevalence of virulence genes commonly found in PAIs associated with ExPEC strains was highly variable, with strains of group 2 harboring most of the virulence genes tested. papG allele III was detected in all strains in group 1 and in one strain in group 3. All other strains were negative for the known alleles encoding PapG adhesins. The association of virulence genes with tRNA genes was characterized in these strains by using pulsed-field gel electrophoresis and DNA hybridization. The insertion site of the foo operon was found at the pheU tRNA locus in 16 of the 18 strains and at the selC tRNA locus in the other 2 strains. Furthermore, 8 of the 18 strains harbored a high-pathogenicity island which was inserted in either the asnT or the asnV/U tRNA locus. These results suggest the presence of one or more PAIs in septicemic strains from animals and the association of the foo operon with at least one of these islands. F165-positive strains share certain virulence traits with ExPEC, and most of them are pathogenic in piglets, as tested in experimental infections. 相似文献
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Faisal K. Algethami Khaled Trabelsi Anouar Hajjaji Mohamed B. Rabha Lotfi Khezami Mohamed R. Elamin Brahim Bessais My Ali El Khakani 《Materials》2022,15(14)
The present work aims to study the photocatalytic properties of nanohybrids composed of silicon nanowires (SiNWs) decorated with PbS nanoparticles (NPs). The elaborated material was intended to be utilized in wastewater treatment. The SiNWs were elaborated from the Metal Assisted Chemical Etching route (MACE), while the PbS NPs were deposited at room temperature onto SiNWs using the pulsed laser deposition (PLD) technique. The influence of decorating SiNWs (having different lengths) with PbS-NPs on their structural, morphological, optoelectronic, and photocatalytic properties was scrutinized. PbS/SiNWs nanohybrids exhibited enhanced photocatalytic degradation towards Black Amido (BA) dye for 20 µm SiNWs length and 0.2% of BA volume concentration. These optimized conditions may insinuate that this nanocomposite-like structure is a promising efficient photocatalytic systems contender, cost-effective, and recyclable for organic compound purification from wastewaters. 相似文献
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We address in the present paper a medical monitoring system designed as a multi-agent based approach. Our system includes mainly numerous agents that act as correlated multi-agent sub-systems at the three layers of the whole monitoring infrastructure, to avoid non informative alarms and send effective alarms at time. The intelligence in the proposed monitoring system is provided by the use of time series technology. In fact, the capability of continuous learning of time series from the physiological variables allows the design of a system that monitors patients in real-time. Such system is a contrast to the classical threshold-based monitoring system actually present in the Intensive Care Units (ICUs) which causes a huge number of irrelevant alarms. 相似文献
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Atef M Darwish Ahmad F Amin Safwat A Mohammad 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2003,7(2):101-106
OBJECTIVES: To define the proportion, methods of diagnosis, and a simplified laparoscopic technique for treating paratubal and paraovarian cysts. METHODS: We conducted a prospective cross-sectional study in the Gynecologic Endoscopy Unit of Assiut University Hospital in Assiut, Egypt in 1853 patients undergoing video-assisted laparoscopy. Transvaginal ultrasonography (TVS) was performed to detect paratubal or paraovarian cysts. Tubal shape and patency were evaluated with hysterosalpingography (HSG) in the infertile group. Diagnostic laparoscopy was performed to confirm the diagnosis of paratubal or paraovarian cysts. Small cysts were punctured and coagulated, and larger cysts required cystectomy and extraction of the cysts by using bipolar electrosurgery. Cystectomy was preceded by endocystic visualization in all cases. The primary outcomes measured included (1) correlation of the preoperative TVS, HSG, or both of these, with the laparoscopic diagnosis; (2) estimation of the success of the laparoscopic management of paratubal cysts; (3) assessment of the value of endocystic visualization prior to cystectomy; and (4) evaluation of tubal patency after laparoscopic management. RESULTS: Laparoscopically, only 118 patients (15.7%) were proved to have paratubal or paraovarian cysts. Preoperatively, TVS confirmed paratubal or paraovarian cysts in 52 (44%) patients. Cysts less than 3 cm in size (34 cases) were treated with simple puncture and bipolar coagulation of the cyst wall, whereas larger cysts (84 cases) were treated by cystectomy. Endocystic visualization using the 4-mm rigid hysteroscope was performed in 84 (71%) patients with large cysts. Statistically significant improvement occurred in tubal patency after laparoscopic management. CONCLUSIONS: Sonographic diagnosis of not uncommon paratubal and paraovarian cysts is not always feasible and requires greater awareness and accuracy. The characteristic laparoscopic differentiation of ovarian cysts is the crossing of vessels over them. Endocystic-endoscopic visualization is a simple, valuable step prior to cystectomy. Bipolar coagulation or extraction of these cysts diagnosed at laparoscopy is easy, not time-consuming, and should be routinely performed in all cases following microsurgical laparoscopic principles. 相似文献
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Chaikof EL Lin PH Brinkman WT Dodson TF Weiss VJ Lumsden AB Terramani TT Najibi S Bush RL Salam AA Smith RB 《Annals of surgery》2002,235(6):833-841
OBJECTIVE: The impact of co-morbid conditions on early and late clinical outcomes after endovascular treatment of abdominal aortic aneurysm (AAA) was assessed in concurrent cohorts of patients stratified with respect to risk for intervention. SUMMARY BACKGROUND DATA: As a minimally invasive strategy for the treatment of AAA, endovascular repair has been embraced with enthusiasm for all prospective patients who are suitable anatomical candidates because of the promise of achieving a durable result with a reduced risk of perioperative morbidity and mortality. METHODS: From April 1994 to March 2001, endovascular AAA repair was performed in 236 patients using commercially available systems. A subset of patients considered at increased risk for intervention (n = 123) were categorized, as such, based on a preexisting history of ischemic coronary artery disease, with documentation of myocardial infarction (60%) or congestive heart failure (35%), or due to the presence of chronic obstructive disease (21%), liver disease, or malignancy. RESULTS: Perioperative mortality (30-day) was 6.5% in the increased-risk patients as compared to 1.8% among those classified as low risk (P = NS). There was no difference between groups in age (74 +/- 9 years vs. 72 +/- 6 years; mean +/- SD), surgical time (235 +/- 95 minutes vs. 219 +/- 84 minutes), blood loss (457 +/- 432 mL vs. 351 +/- 273 mL), postoperative hospital stay (4.8 +/- 3.4 days vs. 4.0 +/- 3.9 days), or days in the ICU (1.3 +/- 1.8 days vs. 0.5 +/- 1.6 days). Patients at increased risk of intervention had larger aneurysms than low-risk patients (59 +/- 13 mm vs. 51 +/- 14 mm; P <.05). Stent grafts were successfully implanted in 116 (95%) increased-risk versus 107 (95%) low-risk patients (P = NS). Conversion rates to open operative repair were similar in increased-risk and low-risk groups at 3% and 5%, respectively. The initial endoleak rate was 22% versus 20%, based on the first CT performed (either at discharge or 1 month; P = NS). To date, increased-risk patients have been followed for 17.4 +/- 15 months and low-risk patients for 16.3 +/- 14 months. Kaplan-Meier analysis for cumulative patient survival demonstrated a reduced probability of survival among those patients initially classified as at increased risk for intervention (P <.05, Mantel-Cox test). Both cohorts had similar two-year primary and secondary clinical success rates of approximately 75% and 80%, respectively. CONCLUSIONS: Early and late clinical outcomes are comparable after endovascular repair of AAA, regardless of risk-stratification. Notably, 2 years after endovascular repair, at least one in five patients was classified as a clinical failure. Given the need for close life-long surveillance and the continued uncertainty associated with clinical outcome, caution is dictated in advocating endovascular treatment for the patient who is otherwise considered an ideal candidate for standard open surgical repair. 相似文献