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1.
S Hakki SJ Harwood MA Morrissey JG Camblin DL Laven WB Webster 《Canadian Metallurgical Quarterly》1997,(335):275-285
When clinical data are insufficient to diagnose infection of bone or joints, nuclear scanning becomes crucial in making an accurate diagnosis. The efficacy of (99m)technetium antigranulocyte monoclonal antibody Fab' fragment (LeukoScan) is prospectively compared with (111)indium white blood cell and (99m)technetium methylene diphosphonate bone scans in 74 patients with suspected musculoskeletal infections. They were grouped according to site of suspected infection: 33 long bones, 23 prosthetic joints, and 18 diabetic feet. Sixty-two of these 74 patients had surgical verification with histopathology or culture. The remaining 12 patients had clinical followup as proof of absence of infection. The overall sensitivity of LeukoScan, (111)indium white blood cell, and (99m)technetium methylene diphosphonate bone scans was 93%, 85% and 92%, respectively. Specificity was 89%, 75% and 52%, and accuracy was 90%, 79% and 74%, respectively. The conclusion from this study is that LeukoScan is more accurate in detecting osteomyelitis, with better sensitivity and specificity in prosthetic joints. Compared with (111)indium white blood cell scans, LeukoScan++ gives superior images, and results are obtained in 1 to 6 hours without biohazard risk from handling blood products. 相似文献
2.
The neuronal nicotinic synapse in tissue slices of the adrenal medulla was studied with whole-cell patch-clamp. Excitatory postsynaptic currents (EPSCs) were evoked by local field stimulation or occurred spontaneously especially when external [K+] was increased. EPSCs were carried by channels sharing biophysical and pharmacological properties of neuronal-type nicotinic receptors (nAChRs). A single-channel conductance (gamma) of 43-45 pS was found from nonstationary variance analysis of EPSCs. Spontaneous EPSCs were tetrodotoxin-insensitive and Ca(2+)-dependent and occurred in burst-like clusters. Quantal analysis of spontaneous EPSCs gave a quantal size of 20 pA and amplitude histograms were well described by binomial models with low values of quantal content, consistent with a small number of spontaneously active release sites. However, rare large amplitude EPSCs suggest that the total number of sites is higher and that extrajunctional receptors are involved. Our estimates of quantal content and size at the chromaffin cell neuronal nicotinic synapse may be useful in characterizing central neuronal-type nicotinic receptor-mediated cholinergic synaptic transmission. 相似文献
3.
AG Niessen JG Bollemeijer RJ de Keizer PH de Meijer 《Canadian Metallurgical Quarterly》1994,138(15):770-775
OBJECTIVE: To assess how often the aetiology is established in patients with uveitis, what systemic disease are found and what is the contribution of the internist to the diagnostic process. DESIGN: Retrospective study. SETTING: University Hospital Leiden, the Netherlands. METHOD: From January 1987 to April 1992, 342 patients presented with uveitis. All patients underwent a standard ophthalmological examination. Referral to an internist and individualised laboratory screening followed in patients with recurrent, chronic, bilateral or panuveitis. Recorded were: ophthalmological data, results of laboratory screening, results of analysis by the internist, final diagnosis and presence of systemic disease. RESULTS: 149 (44%) patients were examined by the internist, 18 (5.2%) were seen by another specialist. In 169 (49%) patients a specific diagnosis was made. 74 (22%) had a systemic disease, 74 a primary ocular disease. In 28 (8%) a systemic disease was presumed (5% were HLA-B27 positive, 3% had abnormal laboratory results); 5 (1%) patients had endophthalmitis as a complication of a septic process. CONCLUSION: In approximately 1/3 of the patients with uveitis a systemic disease was found. Examination by the internist tailored to the individual patient is essential in the evaluation of uveitis patients. 相似文献
4.
5.
Planning is an essential function of project management. Yet, many small- and medium-sized contractors do a relatively poor job of operational planning. Better prebid plans will reduce costs, shorten schedules, and improve labor productivity. Unfortunately, the published literature offers little guidance for smaller contractors on what constitutes effective planning. Most papers describe planning as a macrolevel process for owners. Most emphasize scope definition for industrial projects. This paper describes a microlevel planning process for contractors. It consists of eight steps which are: (1) assess contract risks; (2) develop a preliminary execution plan; (3) develop site layout plans; (4) identify the sequences that are essential-to-success; (5) develop detailed operational plans; (6) develop proactive strategies to assure construction input into design; (7) revise the preliminary plan; and (8) communicate and enforce the plan. The entire process is illustrated with a case study project and is fully illustrated with figures which show how to integrate the work of multiple contractors, keep key resources (crews or equipment) fully engaged with no downtime, provide time buffers so the work of follow on crews can be efficiently done, expedite the schedule using multiple work stations and concurrent work, ways to communicate the work plan to the superintendent and foremen, and how to assess the feasibility of various work methods. The steps are easy to understand and implement. They will yield immediate positive results. 相似文献
6.
C Wang ME Nicol MK Chakrabarti A Holdcroft JG Whitwam 《Canadian Metallurgical Quarterly》1993,16(6):354-357
We compared high frequency ventilation (HFV) to conventional mechanical ventilation (CMV) under normoxic and normocapnic condition in surfactant depleted rabbits with bilateral pneumothoraces. We hypothesized that lower airway pressures would be required with HFV under these conditions. We applied CMV and HFV in 8 anaesthetized rabbits with a prototype ventilator at frequencies of 30, 100, 200, and 300 cycles/min. A positive end-expiratory pressure (PEEP) just below the pressure sufficient to open the air leak from the pneumothoraces was applied at all frequencies. Airway pressures, gas exchange, heart rate, and mean arterial pressure were recorded. Peak airway pressure decreased significantly from 2.50 to 2.10 kPa when the frequency of ventilation was increased from 30 to 300 cycles/min. There were no significant changes in mean airway pressure, PaO2, arterial pH, heart rate, and mean arterial pressure when HFV was compared to CMV. In conclusion, during HFV peak airway pressures measured at the mouth were decreased. Our ability to maintain adequate gas exchange in the face of ongoing pulmonary air leaks may reflect lower alveolar pressures. 相似文献
7.
BACKGROUND: The effects of stroke on classically nondominant hemisphere functions have received less attention than those on the dominant hemisphere, but visuospatial neglect and denial of illness both produce significant morbidity. SUMMARY OF COMMENT: The early literature on denial of illness is discussed and the etiological theories are examined. These are explanations based on deficits of higher mental function, impaired sensory input (especially proprioceptive), an abnormal representation of body image, psychodynamic defense mechanisms, and/or premorbid personality factors. CONCLUSIONS: Denial of illness is an important consequence of stroke. No explanation thus far proposed is entirely satisfactory. The consequences on rehabilitation and strategies for therapy have not been adequately investigated. 相似文献
8.
ST O'Sullivan GT McGreal A Lyons L Burke JG Geoghegan MP Brady 《Canadian Metallurgical Quarterly》1994,47(9):851-852
A case of histologically confirmed Paget's disease of the breast in a 72 year old man, without underlying breast carcinoma, is reported. This report raises questions about the pathogenesis of this condition and suggests that Paget's disease is an independent, intraepidermal carcinoma rather than a direct extension of intraductal carcinoma of the breast to the nipple and areola. 相似文献
9.
BACKGROUND: Previous studies have documented greater use of health services by depressed persons and have postulated that health care costs could be reduced overall through better recognition and treatment of depression. OBJECTIVE: To determine whether a greater burden of medical illness contributes to excess charges for diagnostic tests among older adults with symptoms of depression. DESIGN: Prospective cohort study. SETTING: A primary care group practice at an academic institution. PATIENTS: 3767 patients 60 years of age and older who completed testing on the Centers for Epidemiologic Studies Depression Scale (CES-D) during routine office visits. MEASUREMENTS: Charges for all inpatient and ambulatory diagnostic testing for 2 years, including clinical pathology, diagnostic imaging, and special procedures; number of visits to the ambulatory care center or emergency department; and number of hospitalizations. The Ambulatory Care Group case-mix approach, which is based on ambulatory diagnoses, was used as a measure of health status and expected resource consumption. RESULTS: Patients with symptoms of depression (CES-D scores > or = 16) were significantly younger (66.6 compared with 68.1 years; P < 0.001), more likely to be white (50.5% compared with 33.9%; P = 0.001), and more likely to be female (75.8% compared with 67.6%; P = 0.001) than were those without these symptoms (CES-D scores < 16). They also had more nonpsychiatric comorbid conditions, had more visits to the ambulatory care center (9.2 compared with 7.8; P < 0.001), were more likely to use the emergency department (52.3% compared with 40%; P = 0.001), were more likely to be hospitalized (22.4% compared with 17%; P = 0.002), and had greater median total diagnostic test charges for a period of 1 year ($583 compared with $387; P < 0.001). The difference in charges, most of which were clinical pathology charges (54.2%), persisted into the second year. Ambulatory Care Group assignment was independently associated with diagnostic test charges. The CES-D summary score was not independently associated with diagnostic test charges when controlling for Ambulatory Care Group assignment. CONCLUSIONS: Patients with symptoms of depression accrue greater average diagnostic test charges. However, these data suggest that such patients also have a greater burden of comorbid nonpsychiatric illness. Efforts to improve outcome and decrease cost for patients who have late-life depression must target interventions to improve the care of psychiatric and medical illness concurrently. 相似文献
10.
WI Bensinger KS Schiffman L Holmberg FR Appelbaum R Maziarz P Montgomery E Ellis S Rivkin P Weiden K Lilleby S Rowley S Petersdorf JP Klarnet W Nichols A Hertler R McCroskey CH Weaver CD Buckner 《Canadian Metallurgical Quarterly》1997,19(12):1183-1189
The purpose of this study was to determine the outcome of patients with metastatic breast cancer treated with high-dose busulfan (Bu), melphalan (Mel) and thiotepa (TT) followed by peripheral blood stem cell (PBSC) infusion. Fifty-one patients with chemotherapy refractory (n = 32) or responsive (n = 19) metastatic breast cancer received Bu (12 mg/kg), Mel (100 mg/m2) and TT (500 mg/m2) followed by PBSC collected after chemotherapy and growth factor (n = 43) or growth factor alone (n = 8). The 100 day treatment-related mortality was 8% including one death from cytomegalovirus pneumonia, one from aspiration pneumonia and two from regimen-related toxicity (RRT). Seven of 28 refractory (25%) and 5/7 (71%) responsive patients with evaluable disease achieved a complete response of all measurable disease or all soft tissue disease with at least improvement in bone lesions (PR*). Fifteen of 51 patients (29%) are alive and progression-free a median of 423 days (range 353-934) after treatment, 5/32 (16%) with refractory disease and 10/19 (53%) with responsive disease. The probabilities of progression-free survival (PFS) at 1.5 years for the patients with refractory (n = 32) and responsive (n = 19) disease were 0.24 and 0.53, respectively. These preliminary data suggest that high-dose Bu/Mel/TT has significant activity in patients with advanced breast cancer and may be superior to some previously published regimens. 相似文献