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NH Hwang RS Meltzer MA Moehring JD Thomas BF Vandenberg AP Yoganathan 《Canadian Metallurgical Quarterly》1996,42(1):24-26
Three study sites along the roads with different automobile traffic densities were selected and cattle milk samples were collected every month from all the three sites. Lead concentration in samples were determined through atomic absorption spectrometer. Milk collected from area of heavy traffic contained 4.6-7.2 ppm of Pb, which is much higher than its permissible limit (0.3 ppm) according to FDA. 相似文献
887.
RS Stern 《Canadian Metallurgical Quarterly》1998,134(9):1089-1091
OBJECTIVE: To document changes in type of financing for office-based visits for the treatment of common skin conditions and to dermatologists. DESIGN: Data from a national survey of visits to office-based practitioners conducted by the National Center for Health Statistics were used. The stratified sampling technique permits estimation of the total number of office visits with specific characteristics in the United States. SETTING: A national probability sample of visits to office-based practitioners occurring in 1995. SUBJECTS: In 1995, 36,875 visits were sampled. Of these, 2121 were for common skin problems to any physician and 1886 were visits for any reason to dermatologists. MAIN OUTCOME MEASURES: The distribution source of payment and presence of managed care arrangements for office visits for common skin problems and to dermatologists. INTERVENTION: None. RESULTS: In 1995, preferred provider and health maintenance organizations provided payment for 34% of all ambulatory care and 38% of office visits for common skin complaints. CONCLUSION: Managed care is already the dominant mechanism of payment for the treatment of skin disease for many patient groups and in many areas of the country. Preferred provider organizations are much more likely to employ dermatologists to provide care of common skin problems than are health maintenance organizations. If the recent trends continue, by year 2000 most patients seen by dermatologists will be seen under the auspices of managed care systems. 相似文献
888.
MD Pegram RS Finn K Arzoo M Beryt RJ Pietras DJ Slamon 《Canadian Metallurgical Quarterly》1997,15(5):537-547
INTRODUCTION: Determination of the optimal electrode configuration during implantable cardioverter defibrillator (ICD) implantation remains largely an empirical process. This study investigated the feasibility of using a finite element model of the thorax to predict clinical defibrillation metrics for internal defibrillation in humans. Computed defibrillation metrics from simulations of three common electrode configurations with a monophasic waveform were compared to pooled metrics for similar electrode and waveform configurations reported in humans. METHODS AND RESULTS: A three-dimensional finite element model was constructed from CT cross-sections of a human thorax. Myocardial current density distributions for three electrode configurations (epicardial patches, right ventricular [RV] coil/superior vena cava [SVC] coil, RV coil/SVC coil/subcutaneous patch) and a truncated monophasic pulse with a 65% tilt were simulated. Assuming an inexcitability threshold of 25 mA/cm2 (10 V/cm) and a 75% critical mass criterion for successful defibrillation, defibrillation metrics (interelectrode impedance, defibrillation threshold current, voltage, and energy) were calculated for each electrode simulation. Values of these metrics were within 1 SD of sample-size weighted means for the corresponding metrics determined for similar electrode configurations and waveforms reported in human clinical studies. Simulated myocardial current density distributions suggest that variations in current distribution and uniformity partially explain differences in defibrillation energy requirements between electrode configurations. CONCLUSION: Anatomically realistic three-dimensional finite element modeling can closely simulate internal defibrillation in humans. This may prove useful for characterizing patient-specific factors that influence clinically relevant properties of current density distributions and defibrillation energy requirements of various ICD electrode configurations. 相似文献
889.
A phase I study of TNP-470 administered to patients with advanced squamous cell cancer of the cervix
AP Kudelka T Levy CF Verschraegen CL Edwards S Piamsomboon W Termrungruanglert RS Freedman AL Kaplan DG Kieback CA Meyers KA Jaeckle E Loyer M Steger R Mante G Mavligit A Killian RA Tang JU Gutterman JJ Kavanagh 《Canadian Metallurgical Quarterly》1997,3(9):1501-1505
A Phase I study of the novel angiogenesis inhibitor TNP-470 was performed. Patients with inoperable recurring or metastatic squamous cell cancer of the cervix with evaluable disease, no coagulopathy, and adequate renal, hepatic, and hematological function were eligible. One course of treatment consisted of an i.v. infusion of TNP-470 over 60 min every other day for 28 days, followed by a 14-day rest period. The starting dose was 9.3 mg/m2. Eighteen evaluable patients were treated, with a median age of 48 years (range 27-55) and performance status Zubrod 1 (range 0-2). Grade 3 neurotoxicities consisting of weakness, nystagmus, diplopia, and ataxia were encountered in two patients receiving the 71.2 mg/m2 dose. An intermediate dose level of 60 mg/m2 was evaluated and found to be well tolerated by three patients. Only one patient experienced grade 3 nausea on the 60 mg/m2 dose level. No myelosuppression, retinal hemorrhage, weight loss, or significant alopecia were observed. One patient had a complete response, which continues for 26 months, and three patients with initially progressive disease stage had stable disease for 5, 7.7, and 19+ months. Other Phase I studies, including over 200 patients, were performed concurrently with this study. Based on this experience, the dose of TNP-470 recommended for further studies is 60 mg/m2 as a 60-min i.v. infusion every Monday, Wednesday, and Friday. Neurotoxicity was dose limiting, but appears to be reversible. Otherwise, the treatment was well tolerated. The drug may be active in squamous cell cancer of the cervix. Further studies of TNP-470 in squamous cell cancer of the cervix are warranted. 相似文献
890.
RS McCuskey J Nishida D McDonnell C Williams O Koldovsky 《Canadian Metallurgical Quarterly》1997,71(3):202-206
A Rehabilitation Information System was created in July 1993 in order to register war victims in need of physical rehabilitation all over Croatia. The system is currently operating and presented data covers the period from July 1991 to July 1995. Approximately 15,000 questionnaires had been completed and returned from medical institutions on in total 8589 disabled war victims in need of rehabilitation. People with severe disabilities comprised about 20% of all in need of rehabilitation. Those reported injured were 3.5 times more than those in need of physical rehabilitation. Most common types of injuries were fractures with a permanent disabling condition (3109 persons), peripheral nerve injuries (1213 persons) and amputations (956 persons). Traumatic brain injuries were registered for 594 and spinal cord injuries for 262 persons. Causes of injuries were explosive devices (such as mines, mortar shell shrapnel, etc.) in 37% of cases, bullets in 22%, accidents in 7%, other (such as fire, blast injuries, etc.) and unknown causes in 34%. 相似文献