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11.
OBJECTIVE: To evaluate the dynamics of bacterial contamination of healthcare workers' (HCWs) hands during neonatal care. SETTING: The 20-bed neonatal unit of a large acute care teaching hospital in Geneva, Switzerland. METHODS: Structured observation sessions were conducted. A sequence of care began when the HCW performed hand hygiene and ended when the activity changed or hand hygiene was performed again. Alcohol-based handrub was the standard procedure for hand hygiene. An imprint of the five fingertips of the dominant hand was obtained before and after hand hygiene and at the end of a sequence of care. Regression methods were used to model the final bacterial count according to the type and duration of care and the use of gloves. RESULTS: One hundred forty-nine sequences of care were observed. Commensal skin flora comprised 72.4% of all culture-positive specimens (n = 360). Other microorganisms identified were Enterobacteriaceae (n = 55, 13.8%); Staphylococcus aureus (n = 10, 2.5%); and fungi (n = 7, 1.8%). Skin contact, respiratory care, and diaper change were independently associated with an increased bacterial count; the use of gloves did not fully protect HCWs' hands from bacterial contamination. CONCLUSIONS: These data confirm that hands become progressively contaminated with commensal flora and potential pathogens during neonatal care, and identify activities at higher risk for hand contamination. They also reinforce the need for hand hygiene after a sequence of care, before starting a different task, and after glove removal.  相似文献   
12.
Peripheral quantitative computed tomography (pQCT) has mainly been used as a research tool in children. To evaluate the clinical utility of pQCT and formulate recommendations for its use in children, the International Society of Clinical Densitometry (ISCD) convened a task force to review the literature and propose areas of consensus and future research. The types of pQCT technology available, the clinical application of pQCT for bone health assessment in children, the important elements to be included in a pQCT report, and quality control monitoring techniques were evaluated. The review revealed a lack of standardization of pQCT techniques, and a paucity of data regarding differences between pQCT manufacturers, models and software versions and their impact in pediatric assessment. Measurement sites varied across studies. Adequate reference data, a critical element for interpretation of pQCT results, were entirely lacking, although some comparative data on healthy children were available. The elements of the pQCT clinical report and quality control procedures are similar to those recommended for dual-energy X-ray absorptiometry. Future research is needed to establish evidence-based criteria for the selection of the measurement site, scan acquisition and analysis parameters, and outcome measures. Reference data that sufficiently characterize the normal range of variability in the population also need to be established.  相似文献   
13.
 Organophosphorus nerve agents are still in use today in warfare and as terrorism compounds. Classical emergency treatment of organophosphate poisoning includes the combined administration of a cholinesterase reactivator (an oxime), a muscarinic cholinergic receptor antagonist (atropine) and a benzodiazepine anticonvulsant (diazepam). However, recent experiments with primates have demonstrated that such treatment, even when administered immediately after organophosphate exposure, does not rapidly restore normal electroencephalographic (EEG) activity and fails to totally prevent neuronal brain damage. The objective of this study was to evaluate, in a realistic setting, the therapeutic benefit of administration of GK-11 (gacyclidine), an antiglutamatergic compound, as a complement to the available emergency therapy against organophosphate poisoning. GK-11 was injected at a dose of 0.1 mg/kg (i.v) after a 45-min latency period to heavily intoxicated (8 LD50) primates. Just after intoxication, man-equivalent doses of one autoinjector containing atropine/pralidoxime/diazepam were administered. The effects of GK-11 were examined on survival, EEG activity, signs of toxicity, recovery after challenge and central nervous system histology. The present data demonstrate that treatment with GK-11 prevents the mortality observed after early administration of classical emergency medication alone. EEG recordings and clinical observations also revealed that GK-11 prevented soman-induced seizures and motor convulsions. EEG analysis within the classical frequency bands (beta, theta, alpha, delta) demonstrated that central activity was totally restored to normal after GK-11 treatment, but remained profoundly altered in animals receiving atropine/pralidoxime/diazepam alone. GK-11 also markedly accelerated clinical recovery of soman-challenged primates. Lastly, this drug totally prevented the neuropathology observed 3 weeks after soman exposure in animals treated with classical emergency treatment alone. GK-11 represents a promising adjuvant therapy to the currently available emergency polymedication to ensure optimal management of organophosphate poisoning in man. This drug is presently being evaluated in a human clinical trial for a different neuroprotective indication. Received: 16 June 1997 / Accepted: 23 September 1997  相似文献   
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Abstract End-stage liver disease caused by the hepatitis C virus is a major indication for liver transplantation. However, recurrence of hepatitis in the graft is a major issue. HCV re-infection after transplantation is almost constant, and recent data confirm that it significantly impairs patient and graft survival. Factors that may influence disease severity and consequent progression of HCV graft injury remain unclear. Chronic HCV infection develops in 60%–80% of patients, and 6%–28% ultimately progress to cirrhosis within 5 years. Pre-transplantation antiviral treatment is not easily related to poor tolerance. Attempts to administer prophylactic post-transplantation antiviral treatment are under evaluation but are limited by antiviral drug side effects. Treatment of established graft lesions with interferon or ribavirin as single agents has been disappointing. Combination therapy gave promising results, with sustained virological response in 25% of patients, but indications, modality and duration of treatment should be assessed.  相似文献   
16.
By immunoblotting with an antiserum raised against purified listeriolysin O, we have detected the presence of a truncated protein of 52 kilodaltons in culture supernatants of a Tn1545-induced nonhemolytic mutant of Listeria monocytogenes (J.L. Gaillard, P. Berche, and P. Sansonetti, Infect. Immun. 52:50-55, 1986). The region of insertion of the transposon has been cloned and sequenced. The transposon had inserted in an open reading frame the listeriolysin O gene. The deduced amino acid sequence of this open reading frame revealed that listeriolysin O is homologous to streptolysin O and pneumolysin, although homologies were not detectable at the DNA level.  相似文献   
17.
Abstract The outcome of OLT for HBV-related liver disease is dependent on the prevention of allograft re-infection. Over the past decade, major advances have been made in the management of HBV transplant candidates. The advent of long-term hepatitis B immune globulin (HBIG) administration as a prophylaxis against HBV recurrence, and the introduction of new antiviral agents against HBV infection, such as lamivudine (LAM), were a major breakthrough in the management of these patients. Results of OLT for HBV infection are similar to those achieved with other indications. Pre-OLT antiviral treatment such as LAM can suppress HBV replication before OLT and thus decrease the risk of re-infection of the graft. Combination prophylaxis with LAM and HBIG after transplantation highly effectively reduces the rate of HBV re-infection, even in HBV replicative cirrhotic, patients. The optimal HBIG protocol in the LAM era is yet to be defined: dosing of HBIG, routes of administration, and possibility of stopping HBIG. Several antiviral drugs have been developed for the management of HBV infection on the graft, so outcome is currently good.  相似文献   
18.
The European Society of Thoracic Surgeons (ESTS) organized a workshop dealing with lymph node staging in non-small cell lung cancer. The objective of this workshop was to develop guidelines for definitions and the surgical procedures of intraoperative lymph node staging, and the pathologic evaluation of resected lymph nodes in patients with non-small cell lung cancer (NSCLC). Relevant peer-reviewed publications on the subjects, the experience of the participants, and the opinion of the ESTS members contributing on line, were used to reach a consensus. Systematic nodal dissection is recommended in all cases to ensure complete resection. Lobe-specific systematic nodal dissection is acceptable for peripheral squamous T1 tumors, if hilar and interlobar nodes are negative on frozen section studies; it implies removal of, at least, three hilar and interlobar nodes and three mediastinal nodes from three stations in which the subcarinal is always included. Selected lymph node biopsies and sampling are justified to prove nodal involvement when resection is not possible. Pathologic evaluation includes all lymph nodes resected separately and those remaining in the lung specimen. Sections are done at the site of gross abnormalities. If macroscopic inspection does not detect any abnormal site, 2-mm slices of the nodes in the longitudinal plane are recommended. Routine search for micrometastases or isolated tumor cells in hematoxylin-eosin negative nodes would be desirable. Randomized controlled trials to evaluate adjuvant therapies for patients with these conditions are recommended. The adherence to these guidelines will standardize the intraoperative lymph node staging and pathologic evaluation, and improve pathologic staging, which will help decide on the best adjuvant therapy.  相似文献   
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Background: The qualities of visual perception and of motor reaction to the visual stimulus have never been studied in reference to the type of video-camera system (2-D vs 3-D) used during laparoscopy. Methods: The study was designed in two parts. The first evaluated the ability of the eye to discriminate how objects are spaced relative to one another. The second investigated the motor reaction to the visual stimulus in an environment where depth was the preponderent cue. The tests were performed in a pelvi-trainer in which were inserted different modules built either for visual observation (Part 1) or for evaluation of motor ability (Part 2). Variables studied during Part 1 were the time required to do the test and the number of errors committed during its performance. The variable evaluated during Part 2 was the time needed to terminate the test. Each of these two parts of the study were completed alternating the 2-D and 3-D systems. A total of 304 observations were recorded. Statistics used were the paired t-test, the independent group t-test, and the Newman-Keuls multiple comparisons test. Results: Results of Part 1 of the study confirm that visual perception varies significantly among individuals (n = 10) (p < 0.05) and that a true 3-D video-camera system facilitates visual perception when compared to a 2-D system (p < 0.001). Results of Part 2 of the study also show significant differences among participants (n= 9) (p < 0.05). The true 3-D system allowed significantly faster motor performances than the 2-D system (p < 0.001). Conclusion: Our experiment shows that the 3-D system allowed significant improvements in the execution of the evaluated parameters. Also noted were significant differences among participants in term of visual and motor skills.  相似文献   
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