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871.
OBJECTIVE: To evaluate the performance of a novel computerized system for reporting clinical microbiology results. The new system provides a summarized overview of a patient's current (or past) microbiological status, with the option to selectively explore in greater depth. It is deployed using World Wide Web technology, which supports virtually any kind of computer and allows physicians to obtain results via the internet using personal computers in the office or at home. METHODS: In an unblinded crossover study at a university-affiliated medical center, participants used both the new system and a conventional display system to retrieve selected microbiology results for two actual patients, according to standardized questionnaires, with balanced allocation of sequence of system use. Participants also subjectively rated the two systems. The participants were 16 physician, pharmacist, and nurse volunteers. Outcome measures included completion time and number of errors (categorized as major and minor) associated with results retrieval, and participants' ratings of the new system. RESULTS: Mean completion time was 45% shorter (13.9 versus 25.5 minutes; P < 0.001), and there were fewer associated major errors (0 versus 13; P = 0.01) and minor errors (10 versus 21; P = 0.003) with the summarized display system. All participants rated the new system as easier to learn and use than the conventional system. CONCLUSIONS: A system that appropriately summarizes and groups microbiology results can significantly shorten retrieval times and reduce interpretive errors, while providing users with information needed for cost-effective therapy. Such a system can be deployed by leveraging the rapidly evolving technology of the World Wide Web. 相似文献
872.
In this study, naturally-occurring, monoclonal IgM kappa anti-thymocyte autoantibodies from the neonatal inbred Balb/c mouse-derived hybridoma NMT-1 (NMT-1 mAb), previously reported to identify a restricted CD4+CD8+CD3/lo/int thymocyte subpopulation, have been shown to exhibit extensive polyspecificity. Using immunofluorescence, immunoblotting and antibody titration and competition ELISAs, NMT-1 mAbs exhibited polyspecific binding to 12 apparently structurally unrelated self and non-self antigens. The autoreactive component of the polyspecificity profile of NMT-1 mAbs encompassed reactivity to developmentally-related 14.5 and 18.3 kDa Thy-1 glycoforms expressed on a CD4+CD8+CD3-/lo/int thymocyte subpopulation. The autoreactivity profile of NMT-1 mAbs also included recognition of the heavy and light chains of mouse IgG1 and mouse cytokeratins within thymic medullary epithelium and basal epithelial cells of stratified squamous epithelium of mouse tongue, oesophagus, stomach, skin and vagina. Examination of the polyspecificity profile of NMT-1 mAbs was also undertaken using a panel of 23 antigens including heterologous proteins, phospholipids, haptens and bacterial antigens by antibody titration and competition ELISAs. Antibody titration ELISAs demonstrated that NMT-1 mAbs bound nine antigens including bovine carbonic anhydrase, ovalbumin, cardiolipin, phosphatidylserine, the haptens, DNP and FITC and the bacterial antigens including Escherichia coli beta-galactosidase and the toxoids from Corynebacterium tetani and Clostridium diphtheria. Competition ELISAs, based on the inhibition of NMT-1 mAb binding to antigens adsorbed to ELISA plate surfaces by inhibitor antigens in solution, demonstrated that NMT-1 mAb interactions were not dependent on multivalent binding. In these assays, NMT-1 mAbs recognized unmodified (native) epitopes on the solution phase forms of the protein antigens, including E. coli beta-galactosidase and toxoids from Corynebacterium tetani and Clostridium diphtheria, providing further evidence for the hypothesis that the binding of multiple, apparently unrelated, antigens by NMT-1 mAbs occurs via unique polyspecific antigen combining sites. 相似文献
873.
Vocal fold scarring: current concepts and management 总被引:1,自引:0,他引:1
MS Benninger D Alessi S Archer R Bastian C Ford J Koufman RT Sataloff JR Spiegel P Woo 《Canadian Metallurgical Quarterly》1996,115(5):474-482
Scarring of the vocal folds can occur as the result of blunt laryngeal trauma or, more commonly, as the result of surgical, iatrogenic injury after excision or removal of vocal fold lesions. The scarring results in replacement of healthy tissue by fibrous tissue and can irrevocably alter vocal fold function and lead to a decreased or absent vocal fold mucosal wave. The assessment and treatment of persistent dysphonia in patients with vocal fold scarring presents both diagnostic and therapeutic challenges to the voice treatment team. The common causes of vocal fold scarring are described, and prevention of vocal fold injury during removal of vocal fold lesions is stressed. The anatomic and histologic basis for the subsequent alterations in voice production and contemporary modalities for clinical and objective assessment will be discussed. Treatment options will be reviewed, including nonsurgical treatment and voice therapy, collagen injection, fat augmentation, endoscopic laryngoplasty, and Silastic medialization. 相似文献
874.
875.
876.
JR Woods 《Canadian Metallurgical Quarterly》1993,56(3):3-21
Vesting among full-time private sector employees has increased dramatically over the past two decades. With further increases expected, it seems likely that almost all workers covered by a pension plan will eventually receive some kind of benefit. Coverage, however, remains a problem. According to the most recently available data, only 46 percent of full-time private employees in 1988 were covered by a pension plan on their current jobs, 35 percent were vested, and an additional 4 percent were vested from a previous job. Vesting rates would have been higher if some workers had not cashed out their retirement benefits when they left previous jobs, but the impact is slight; most lump-sum recipients were also vested or covered on their current jobs. Vesting is higher among older workers and among men, though the gender gap has narrowed appreciably over time. Based on trends in vesting and 1988 rates for all types of workers aged 50-59, the analysis suggests that pension receipt rates among the elderly will continue to increase over the next decade. 相似文献
877.
We present two cases of community acquired pneumonia (extra-hospital) of severe onset, secondary to Chlamydia psittaci of avian origin. Each patient have bought a parakeet in the same pet-shop, and took care of them personally. Both developed a respiratory insufficiency, one of them needing mechanical ventilation. Out of nine relatives to whom serological determinations were performed, there was evidence of infection in two of them, but only one referred an auto-limited febrile syndrome during that period of time. Psittacosis incidence is discussed as origin of community acquired pneumonias, as well as its epidemiology, diagnosis and treatment. 相似文献
878.
PR Gibson JR Fraser JC Colman PA Jones G Jennings FJ Dudley 《Canadian Metallurgical Quarterly》1993,105(2):470-474
BACKGROUND: Hyaluronan is an endogenous polysaccharide whose clearance from the plasma is predominantly by liver sinusoidal cells and is sinusoidal flow dependent. This study was designed to determine if a change in serum hyaluronan might reliably reflect short-term drug-induced changes in sinusoidal perfusion. METHODS: Hemodynamic changes following an oral dose of ketanserin were compared with changes in serum hyaluronan levels in 12 patients with alcoholic liver disease and portal hypertension. Indices determined comprised heart rate, mean arterial pressure (MAP), cardiac output (CO), systemic vascular resistance, hepatic venous pressure gradient (HVPG), indocyanine green (ICG) clearance and extraction, and total hepatic blood flow. Measurements were made in a basal state 1 hour after ketanserin ingestion and expressed as a ratio of values post- to pre-ketanserin administration. RESULTS: Ketanserin had variable effects comprising both increases and decreases in all indices. On univariate and multivariate analysis, changes in serum hyaluronan concentration (1.05 +/- 0.13, mean +/- SD) significantly correlated with only one index: changes in ICG clearance (0.93 +/- 0.17, r = -0.65, P = 0.02). CONCLUSIONS: Changes in serum hyaluronan levels reflect short-term drug-induced changes in sinusoidal perfusion in patients with alcoholic liver disease and portal hypertension. Serial measurement of serum hyaluronan levels may offer a simple method of screening vasoactive drugs for their short-term effects on sinusoidal perfusion. 相似文献
879.
In the period of 1983-1990, a total of 691 ureteroscopies were performed in 480 patients. The main indications for ureteroscopy were stones, stenoses or making a diagnosis. In one third of the cases, pathology was suspected in the renal pelvis or at the ureteropelvic junction, in one third in the distal third of the ureter, and in the remaining cases, in either the upper or the middle part of the ureter. The most frequent ureteroscopic procedures were diagnostic examination or surveillance and procedures involving treatment of stones. In the 1st attempt, the ureteroscope was introduced to the suspected pathology in 79.9% of all cases, and the main objective was achieved in 76.6%. The success of stone manipulation has increased from 74% in the 1st to 92% in the last part of the period. More than half the procedures involving a ureteral stenosis were not completed satisfactorily. The location of suspected pathology did not influence the results. Complications occurred in 23% of the ureteroscopies, and the relative number of major complications decreased continuously. We conclude that ureteroscopy is appropriate at any location of pathology and that efforts must be made to minimize both major and minor complications. 相似文献
880.
PURPOSE: To quantify regional cerebral blood volume (rCBV) on the basis of the enhancement of blood proton relaxation rates after intravenous administration of gadopentetate dimeglumine. METHODS: A series of sequential MR images on one section was recorded during bolus transit with a standard fast low-angle shot sequence. The signal-intensity curves were converted into corresponding concentration-time curves from which rCBV images were calculated. RESULTS: The functional parameter images of rCBV were calculated pixel-by-pixel for two patients who had received a 1-second bolus injection of 1 mmol of gadopentetate dimeglumine. In a larger series of 62 patients, a mean blood volume of 4.6 +/- 1.6 vol% was determined for normal brain tissue. CONCLUSIONS: The relaxing effect of a contrast agent can be used to determine blood volume quantitatively. The results are in agreement with those obtained by nuclear medicine techniques. The proposed method requires no special hardware, and can thus be implemented on clinical MR scanners. 相似文献