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排序方式: 共有4586条查询结果,搜索用时 15 毫秒
1.
Rene S. Hendriksen Pimlapas Leekitcharoenphon Matthew Mikoleit Jacob Dyring Jensen Rolf Sommer Kaas Louise Roer Heena B. Joshi Srirat Pornruangmong Chaiwat Pulsrikarn Gladys D. Gonzalez-Aviles E. Ascelijn Reuland Nashwan Al Naiemi Astrid Louise Wester Frank M. Aarestrup Henrik Hasman 《Journal of clinical microbiology》2015,53(2):677-680
One unreported case of extended-spectrum-beta-lactamase (ESBL)-producing Salmonella enterica serovar Typhi was identified, whole-genome sequence typed, among other analyses, and compared to other available genomes of S. Typhi. The reported strain was similar to a previously published strain harboring blaSHV-12 from the Philippines and likely part of an undetected outbreak, the first of ESBL-producing S. Typhi. 相似文献
2.
Jennifer C. Sasaki Ashley Allemang Steven M. Bryce Laura Custer Kerry L. Dearfield Yasmin Dietz Azeddine Elhajouji Patricia A. Escobar Albert J. Fornace Jr Roland Froetschl Sheila Galloway Ulrike Hemmann Giel Hendriks Heng-Hong Li Mirjam Luijten Gladys Ouedraogo Lauren Peel Stefan Pfuhler Daniel J. Roberts Véronique Thybaud Jan van Benthem Carole L. Yauk Maik Schuler 《Environmental and molecular mutagenesis》2020,61(1):114-134
In May 2017, the Health and Environmental Sciences Institute's Genetic Toxicology Technical Committee hosted a workshop to discuss whether mode of action (MOA) investigation is enhanced through the application of the adverse outcome pathway (AOP) framework. As AOPs are a relatively new approach in genetic toxicology, this report describes how AOPs could be harnessed to advance MOA analysis of genotoxicity pathways using five example case studies. Each of these genetic toxicology AOPs proposed for further development includes the relevant molecular initiating events, key events, and adverse outcomes (AOs), identification and/or further development of the appropriate assays to link an agent to these events, and discussion regarding the biological plausibility of the proposed AOP. A key difference between these proposed genetic toxicology AOPs versus traditional AOPs is that the AO is a genetic toxicology endpoint of potential significance in risk characterization, in contrast to an adverse state of an organism or a population. The first two detailed case studies describe provisional AOPs for aurora kinase inhibition and tubulin binding, leading to the common AO of aneuploidy. The remaining three case studies highlight provisional AOPs that lead to chromosome breakage or mutation via indirect DNA interaction (inhibition of topoisomerase II, production of cellular reactive oxygen species, and inhibition of DNA synthesis). These case studies serve as starting points for genotoxicity AOPs that could ultimately be published and utilized by the broader toxicology community and illustrate the practical considerations and evidence required to formalize such AOPs so that they may be applied to genetic toxicity evaluation schemes. Environ. Mol. Mutagen. 61:114–134, 2020. © 2019 Wiley Periodicals, Inc. 相似文献
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V L Towle J C Witt S H Nader A T Reder R Foust J P Spire 《Electroencephalography and clinical neurophysiology》1991,80(5):339-346
Pattern visual evoked potentials were obtained from 46 patients with definite relapsing/remitting multiple sclerosis, using both a conventional 5-channel occipital array and a 3-D recording technique consisting of three bipolar derivations approximating the three dimensions of space. These three orthogonal wave forms were displayed as a 3-D Lissajous trajectory for each subject. Two of the 15 patients with completely normal conventional pattern VEPs had abnormalities of the orientation of the B-C curvilinear segment of the 3-D pattern VEPs. Delays in the first major occipital positive component (P100) were evident using both techniques; the correlation between P100 latency and the latency of the corresponding trajectory apex was r = 0.99 (P less than 0.01). Post-chiasmal MRI abnormalities were associated with 3-D VEP orientation abnormalities. Three-dimensional pattern VEPs are moderately more sensitive than conventional pattern VEPs at detecting dysfunction posterior to the optic chiasm in demyelinating disease and do not require the use of eccentric fixation to do so. 相似文献
5.
Hung-Fat Tse Sukumaran Thambar Yok-Lam Kwong Philip Rowlings Greg Bellamy Jane McCrohon Paul Thomas Bruce Bastian John K F Chan Gladys Lo Chi-Lai Ho Wing-Sze Chan Raymond Y Kwong Anthony Parker Thomas H Hauser Jenny Chan Daniel Y T Fong Chu-Pak Lau 《European heart journal》2007,28(24):2998-3005
AIMS: Experimental studies have demonstrated that bone marrow (BM) cells can induce angiogenesis in ischaemic myocardium. Recently, several non-randomized pilot studies have also suggested that direct BM cells implantation appears to be feasible and safe in patients with severe coronary artery diseases (CAD). METHODS AND RESULTS: We performed a randomized, blinded, and placebo-controlled trial in 28 CAD patients. After BM harvesting, we assigned patients to receive low dose (1 x 10(6) cells/0.1 mL, n = 9), high dose (2 x 10(6) cells/0.1 mL, n = 10) autologous BM cells or control (0.1 mL autologous plasma/injection, n = 9) catheter-based direct endomyocardial injection as guided by electromechanical mapping. Our primary endpoint was the increase in exercise treadmill time and our secondary endpoints were changes in Canadian Cardiovascular Society (CCS) and New York Heart Association (NYHA) class, and myocardial perfusion and left ventricular ejection fraction (LVEF) assessed by single-photon emission computed tomography and magnetic resonance imaging, respectively. A total 422 injections (mean 14.6 +/- 0.7 per patient) were successfully performed at 41 targeted ischaemic regions without any acute complication. Baseline exercise treadmill time was 439 +/- 182 s in controls and 393 +/- 136 s in BM-treated patients, and changed after 6 months to 383 +/- 223s and 464 +/- 196 s [BM treatment effect +0.43 log seconds (+53%), 95% CI 0.11-0.74, P = 0.014]. Compared with placebo injection, BM implantation was associated with a significant increase in LVEF (BM treatment effect +5.4%, 95% CI 0.4-10.3, P = 0.044) and a lower NYHA class (odds ratio for treatment effect 0.12, 95% CI 0.02-0.73, P = 0.021) after 6 months, but CCS reduced similarly in both groups. We observed no acute or long-term complications, including ventricular arrhythmia, myocardial damage, or development of intramyocardial tumour or calcification associated with BM implantation. CONCLUSION: Direct endomyocardial implantation of autologous BM cells significantly improved exercise time, LVEF, and NYHA functional class in patients with severe CAD who failed conventional therapy. 相似文献
6.
Central and peripheral effects of oxytocin administration in prairie voles (Microtus ochrogaster) 总被引:3,自引:0,他引:3
The present study examined the hypothesis that oxytocin (OT) may influence female sexual behavior in prairie voles (Microtus ochrogaster). The effectiveness of OT to induce sexual behavior was tested in ovariectomized females that were injected daily with estradiol benzoate (EB, 0.02 micrograms, twice), a dose insufficient for estrus induction. On the third day females received intracerebroventricular (ICV) injections of OT (1, 300, or 1000 ng) or saline vehicle. In the presence of minimal estrogen stimulation, OT did not induce sexual receptivity, or influence autogrooming or other social interactions. The behavioral effects of OT were examined in another group of ovariectomized females that received daily oil or EB injections (10 micrograms, twice) followed on the third day by either ICV (1, 300, or 1000 ng) or intraperitoneal (IP) (1, 3, or 10 micrograms) injections of OT. Among EB-treated females, only those in confirmed estrus, prior to ICV or IP injection, were included in these studies. There was a dose-related decrease in the percentage of females that remained in behavioral estrus after ICV OT. In those females that continued to show sexual behavior, lordosis frequencies and durations were unaffected by ICV OT. Nonsexual behavior did not differ between mated females and those exhibiting OT-inhibited sexual behavior. In females that were EB-treated, autogrooming and side-by-side behavior increased after ICV OT, while there was a decline in aggression. Female sexual and nonsexual behaviors were not significantly affected by IP OT.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
7.
Individuals who undergo head and neck surgery experience extreme stressors that go beyond those which occur with the usual surgical patient. This paper will review the literature and discuss the psychiatric consequences of otolaryngeal surgery. In addition, new head and neck surgical techniques, which offer special challenges to the patient as well as to the psychiatric consultant, will be examined. Tracheostomy, which occurs as a result of head and neck surgery, is of particular importance with regard to postoperative adaptation and is a significant complication that must be reckoned with. 相似文献
8.
Increase in the degree of phosphorylation of circulating fibrinogen under thrombolytic therapy with urokinase 总被引:2,自引:0,他引:2
Human fibrinogen is phosphorylated in vivo to an equal extent at two positions, one at Ser 3 located on fibrinopeptide A, the other at Ser 345 of the A alpha-chain. As has been shown previously, the degree of phosphorylation of the circulating fibrinogen pool can be determined in vitro from the ratio between the HPLC peaks formed by phosphorylated and non-phosphorylated fibrinopeptide A which has been cleaved from plasma fibrinogen by thrombin or reptilase. Plasma samples were obtained from patients with venous thrombosis undergoing fibrinolytic therapy with urokinase (n = 8). The degree of phosphorylation increased from about 35% before treatment to values between 50% and 70% within 48 hours. It remained at these high levels as long as urokinase was administered and declined slowly thereafter. This behaviour of the degree of phosphorylation of fibrinogen is explained by a model which assumes that fibrinogen is secreted in the phosphorylated form and then dephosphorylated in the circulation by an up to now unidentified phosphatase by first order kinetics. When this system is in steady state, the degree of phosphorylation is about 25% under normal conditions. If the elimination rate of fibrinogen is greatly enhanced by fibrinogenolysis the system will approach a new steady state with a higher degree of phosphorylation, the magnitude of which will depend on the new ratio of dephosphorylation and elimination. 相似文献
9.
Deborah Witt Sherman Marianne LaPorte Matzo Patrick Coyne Betty R Ferrell Barbara K Penn 《Journal for nurses in staff development》2004,20(3):103-15; quiz 116-7
Relief of symptoms for patients and families throughout the illness trajectory requires that palliative care practitioners have knowledge and skill, both in assessment and use of pharmacologic and complementary therapies. This article presents the didactic content of symptom assessment and management, and the experiential experiences used in a nondrug laboratory within the End-of-Life Nursing Education Consortium (ELNEC) curriculum. 相似文献
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