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51.
Michael W. Ellis Ryan C. Johnson Katrina Crawford Jeffrey B. Lanier D. Scott Merrell 《Journal of clinical microbiology》2014,52(1):344-346
We describe a cutaneous abscess caused by catalase-negative methicillin-susceptible Staphylococcus aureus subsp. aureus in a patient who was concomitantly colonized with virulent USA300 methicillin-resistant S. aureus (MRSA). Sequencing of the katA gene demonstrated a thymine insertion leading to a frameshift mutation and premature truncation of catalase to 21 amino acids. 相似文献
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We conducted a systematic quantitative meta-review of the literature to provide evidence-based suggestions for the treatment of scaphoid nonunion. This search identified 1,121 articles of which 36 met eligibility requirements. In unstable nonunions, screw fixation with grafting at 94% union was superior to K-wires and wedge grafting (77% union). Immediate mobilization versus 6 weeks or more of casting showed the same union rate of 74%. For avascular necrosis of the proximal fragment, union was achieved in 88% of those patients with a vascularized graft versus 47% with screw and wedge fixation. These results suggest that established unstable nonunions should be treated with screw fixation and wedge grafting. There is not evidence supporting the need for postoperative immobilization in patients with solid screw fixation. A vascularized graft may be preferable for patients with avascular necrosis of the proximal fragment or with a previously failed surgery. 相似文献
55.
Uribe CL Schweikhart SB Pathak DS Dow M Marsh GB 《Journal of healthcare management / American College of Healthcare Executives》2002,47(4):263-279
Medical-error reporting is an essential component for patient safety enhancement. Unfortunately, medical errors are largely underreported across healthcare institutions. This problem can be attributed to different factors and barriers present at organizational and individual levels that ultimately prevent individuals from generating the report. This study explored the factors that affect medical-error reporting among physicians and nurses at a large academic medical center located in the midwest United States. A nominal group session was conducted to identify the most relevant factors that act as barriers for error reporting. These factors were then used to design a questionnaire that explored the likelihood of the factors to act as barriers and their likelihood to be modified. Using these two parameters, the results were analyzed and combined into a Factor Relevance Matrix. The matrix identifies the factors for which immediate actions should be undertaken to improve medical-error reporting (immediate action factors). It also identifies factors that require long-term strategies (long-term strategy factors) as well as factors that the organization should be aware of but that are of lower priority (awareness factors). The strategies outlined in this study may assist healthcare organizations in improving medical-error reporting, as part of the efforts toward patient-safety enhancement. Although factors affecting medical-error reporting may vary between different organizations, the process used in identifying the factors and the Factor Relevance Matrix developed in this study are easily adaptable to any organizational setting. 相似文献
56.
Kothari SN Kaplan BJ DeMaria EJ Broderick TJ Merrell RC 《Journal of laparoendoscopic & advanced surgical techniques. Part A》2002,12(3):167-173
BACKGROUND: We hypothesized that the Minimally Invasive Surgery Trainer (MIST-VR; VP Medical R, London, U.K.) would be as effective as the Yale Laparoscopic Skills Course in improving laparoscopic intracorporeal suturing skills. MATERIALS AND METHODS: Each student made six attempts to tie a knot laparoscopically. Students were then randomized to train on the MIST-VR for five sessions (six skills/session) or the Yale Skills for five sessions (three skills/session) over 5 days. On completion of training, all students were evaluated by a test consisting of six attempts to tie a laparoscopic knot. RESULTS: The percentage improvement in knot tying time did not differ significantly in the pelvic trainer group (30 +/- 21%) (from 443 +/- 135 to 311 +/- 137 seconds) and the MIST-VR group (39 +/- 21%) (from 409 +/- 109 to 256 +/- 140 seconds) (P = 0.308). CONCLUSIONS: The MIST-VR is equivalent to the Yale Skills Course for training in the advanced laparoscopic skill of intracorporeal suturing. 相似文献
57.
The end of the 20th century brought an increased use of computerized technology in medicine and surgery. The development of robotic surgical systems opened new approaches in general and cardiac surgery. Two leading robotic companies, Computer Motion, Inc. and Intuitive Surgical, Inc. have developed the Zeus and Da Vinci respectively, as very effective tools for surgeons to use. Both of them consist of a surgeon console, located far from the operating table, and three robotic arms, which reproduce inside the patient's body the movements performed by the surgeon at the console. The advantages of robotic surgery over laparoscopy and open surgery include: better eye-hand coordination, tremor filtration, steadiness of camera, 3-D vision, motion scale, more degrees of freedom for instruments etc. Of course, there are also some disadvantages, like the lack of tactile feedback, long time of set up, long learning curve, high cost etc. However, the advantages seem to overcome the disadvantages and more and more operations are conducted using robots. The impact of robotics in surgery is therefore very promising and in the future it will probably open even more new ways in the surgical practice and education both in Romania and across the globe. 相似文献
58.
NiX HouY YangR TangX SmithR NicholsonRC 《第二军医大学学报》2005,26(4):435-435
Corticotrophin-releasing hormone (CRH) plays a major role in mechanisms controlling human pregnancy and parturition. Gene regulation by progesterone may be a key point in the control of placental CRH production. Studies in primary placental ceils show that antagonism of progesterone activity or production by RU486 or trilostane leads to an increase in CRH promoter activity. This effect can be reversed by the addition of progesterone. Overexpression of progesterone receptor A (PRA) or glucocorticoid receptor resulted in a decrease in CRH promoter activity following progesterone treatment, whereas an increase in promoter activity was observed with overexpressed PR-B. 相似文献
59.
NiX HouY KingBR TangX ReadMA SmithR NicholsonRC 《第二军医大学学报》2005,26(4):385-385
Placental CRH plays a major role in the mechanisms controlling human pregnancy and parturition. Understanding how placental CRH production is regulated is therefore of importance. Previously we have shown that placental expression of CRH peptide and mRNA are inhibited by estrogens, in contrast to the stimulatory effects of estrogen on hypothalamic CRH production. Our current study found that in placental cells cotransfected with a CRH promoter construct and an estrogen receptor-alpha expression vector results in a differential regulation whereby 17beta estradiol (E2) decreased and the putative pure estrogen antagonist, ICI 182780, 相似文献
60.
Background: Advanced laparoscopic procedures require prolonged pneumoperitoneum. Increased intra-abdominal pressure causes a number of
hemodynamic changes including a drop in cardiac output, but it is unclear whether there is a direct effect on cardiac contractility.
In this experimental study, we sought to determine whether there is a direct impact of pneumoperitoneum on cardiac contractility.
We also examined the time-related changes taking place during the insufflation period.
Methods: Six young pigs were anesthetized and mechanically ventilated. Pneumoperitoneum was established by insufflating carbon dioxide
to a pressure of 15 mmHg and maintained for a period of 180 min. Hemodynamic parameters including left ventricular dP/dT were
invasively recorded every 15 min. All hemodynamic changes were statistically evaluated, and parameters were correlated with
time.
Results: Cardiac output decreased with insufflation from a baseline of 3.37 ± 0.34 lt/min and reached the lowest value at 165 min
of pneumoperitoneum (2.86 ± 0.30 l/min; p= 0.023). Systemic vascular resistance (SVR) significantly increased from 2236 ± 227 dyne/s/cm5 to a maximum of 3774 ± 324 dyne/s/cm5 (p= 0.005). Left ventricular dP/dT maximum did not change significantly with insufflation. The decrease in cardiac output strongly
correlated with the increase in SVR (r=−0.949). Time of insufflation correlated with cardiac output (r=−0.762) and dP/dT maximum (r=−0.727).
Conclusions: Pneumoperitoneum at 15 mmHg negatively affects cardiac output without significantly affecting cardiac contractility. A significant
increase in SVR appears to be the driving event for the decreased cardiac output. Prolonged pneumoperitoneum may have an additional
negative effect on hemodynamic parameters.
Received: 5 January 2000/Accepted: 4 May 2000/Online publication: 26 July 2000 相似文献