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排序方式: 共有759条查询结果,搜索用时 46 毫秒
101.
102.
EF Smit E Fokkema B Biesma HJ Groen W Snoek PE Postmus 《Canadian Metallurgical Quarterly》1998,77(2):347-351
Deep vein thrombosis (DVT) and pulmonary embolism (PE) are major complications associated with total knee arthroplasty. The American College of Chest Physicians recommends twice-daily, fixed-dose low-molecular-weight heparin (LMWH) as routine prophylaxis in this patient population. This study represents a cost analysis of ardeparin and enoxaparin, the two LMWHs currently available for this indication in the United States. Costs for treating DVT, PE, and major bleeding episodes were derived from values reported in the literature. Both ardeparin and enoxaparin were found to produce significant cost savings when used routinely as DVT prophylaxis after knee replacement surgery compared with no prophylaxis. Based on the currently available data, enoxaparin 40 mg once daily appears to be the least costly LMWH for routine pharmacoprophylaxis of DVT in patients undergoing knee replacement surgery. 相似文献
103.
FO Omara D Flipo C Brochu F Denizeau P Brousseau EF Potworowski M Fournier 《Canadian Metallurgical Quarterly》1998,54(7):561-577
Rat splenocyte mixed leukocyte reaction (MLR), splenic natural killer (NK) cell activity, and phagocytic activities of splenic, peritoneal, and peripheral blood leukocytes (PBLs) were evaluated in vitro to determine the immunotoxicity of mixtures containing low levels of methylmercury (MeHg), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and Aroclor polychlorinated biphenyls (PCBs). The mixtures were based on the concentrations of the chemicals in fish flesh. Leukocytes from male Fischer rats were exposed to MeHg (0.1-2 microg/ml), PCDD/PCDF mixtures (1-15 pg/ml) of three PCDDs (2,3,7,8-tetrachlorodibenzo-p-dioxin, 1,2,3,7,8-pentachlorodibenzo-p-dioxin, and 1,2,3,4,7,8-hexachlorodibenzo-p-dioxin) and two PCDFs (2,3,7,8-tetrachlorodibenzofuran and 1,2,3,7,8-pentachlorodibenzofuran), three Aroclor PCB (Aroclor 1242, 1254, and 1260) mixtures (0.01-0.5 microg/ml), or combinations of MeHg/PCB/PCDD/PCDF mixtures for 24 or 72 h before immunological assays. Phagocytosis and NK cell cytotoxicity were evaluated with a flow cytometer, and MLR of Fischer rat responder splenocytes cultured with mitomycin C-treated Long-Evans splenocytes by [3H]thymidine uptake. Exposure to MeHg (2 microg/ml) alone or with PCB/ PCDD/PCDF resulted in significant cytolethality in rat splenocytes, peritoneal leukocytes, and PBLs at 24 h exposure. Treatment with Aroclor PCB mixtures, PCDD/PCDF mixtures, 0.1 microg MeHg/ml (noncytolethal), or PCB/PCDD/PCDF mixtures with 0.1 microg MeHg/ml caused no suppression of splenocyte MLR response, splenic NK cell-mediated lysis of Yac-l cells, or phagocytosis of fluorescent beads by splenic, peritoneal, and peripheral blood phagocytic cells. The results indicate that in vitro exposure of rat leukocytes to low levels of MeHg, Aroclor PCB mixtures, PCDD/PCDF mixtures, or MeHg/PCB/PCDD/PCDF mixtures had no suppressive effects on the immune functions assayed, and thus produced no additive immunotoxicity. However, in order to predict the potential risk of these chemical mixtures to the human immune system, in vivo animal studies with blood (tissue) levels compatible with the levels of MeHg, PCBs, and PCDDs/PCDFs in exposed human populations should be evaluated. 相似文献
104.
BACKGROUND: Simultaneous abuse of cocaine and alcohol is widespread and increasingly detected in patients seeking emergent care. This double-blind, randomized, within-subjects study used a paradigm more closely approximating practices of drug abusers to better understand the pathogenesis of cocaine-alcohol abuse. METHODS: Subjects meeting DSM-IV criteria for cocaine dependence and alcohol abuse participated in three drug administration sessions: four doses of intranasal cocaine (1 mg/kg every 30 min) with oral alcohol (1 g/kg) administered following the initial cocaine dose and a second dose (120 mg/kg) at 60 min calculated to maintain plasma alcohol concentration at approximately 100 mg/dL during cocaine administration; four doses of cocaine/placebo alcohol; four doses of cocaine placebo/alcohol. Pharmacokinetic, physiological, and behavioral effects were followed over 8 hours. RESULTS: Cocaine-alcohol produced greater euphoria and increased perception of well-being relative to cocaine. Heart rate significantly increased following cocaine-alcohol administration relative to either drug alone. Cocaine concentrations were greater following cocaine-alcohol administration. Cocaethylene had a longer halflife with increasing concentrations relative to cocaine at later time points. CONCLUSIONS: Enhanced psychological effects during cocaine-alcohol abuse may encourage ingestion of larger amounts of these substances over time placing users at heightened risk for greater toxicity than with either drug alone. 相似文献
105.
Comparing the severity of obstructive sleep apnea in patients referred by urban and rural physicians
WV McCall DL Reynolds DM Reboussin EF Haponik B Cooper JD Edinger 《Canadian Metallurgical Quarterly》1998,59(6):358-361
The occurrence of a subdural hematoma caused by the rupture of an intracranial aneurysm is rare. In our case, the patient is a 43-year-old woman who suffered from sudden onset of severe headache. Computed tomographic (CT) scan disclosed a subdural hematoma associated with subarachnoid hemorrhage. CT angiography and digital subtraction angiography revealed an elongated aneurysm adhering to the dura in the left Sylvian fissure. The subdural hematoma was evacuated and the aneurysm clipped. The patient made a full recovery. 相似文献
106.
IJ Diel EF Solomayer SD Costa C Gollan R Goerner D Wallwiener M Kaufmann G Bastert 《Canadian Metallurgical Quarterly》1998,339(6):357-363
We report an unusual case of peripheral primitive neuroectodermal tumor (pPNET) in an infant presenting with congenital cutaneous nodules and a t(7;22)(p21;q11.2). The biologic behavior of the tumor diverged over time from a slowly growing tumor with multiple cutaneous nodules to a more aggressive neoplasm characterized by pulmonary metastases and a soft tissue mass showing additional cytogenetic alterations. 相似文献
107.
L von Berger I Henrichs S Raptis E Heinze W Jonatha WM Teller EF Pfeiffer 《Canadian Metallurgical Quarterly》1976,58(2):264-267
Plasma gastrin was determined simultaneously in 19 newborn infants and their respective mothers shortly after birth and in ten neonates before and after the first feeding. The gastrin concentrations in the umbilical vein plasma of the newborn infants were significantly higher than in the peripheral vein plasma of their mothers. The values were statistically not different from those obtained in the neonates before the first feeding. There was an increase in gastrin concentrations after the first feeding. From these results it is suggested that gastrin is produced in the neonate independently from the mother. It is already secreted after the first feeding. Experiments in rats showed that 125I-gastrin is not transported through the placenta. From these findings we assume that most likely the gastrin measured in plasma of newborn infants is of neonatal origin. 相似文献
108.
Seven general surgeons in a prepaid group practice previously shown to have a mean operative work load of 9.2 hernia equivalents (HE) per week were found to have a standardized mean daytime working week of 56.2 hours, exclusive of evening activities of which 50.7 hours were devoted to professional activities. The surgeons also devoted a mean of 6.7 evening hours per week to professional activities for a mean net professional week of 57.4 hours. Comparisons with a population of previously studied community surgeons revealed that the prepaid group surgeons were able to produce a surgical output more than double that of the community surgeons while devoting only one and a half as much time to professional activities. Economies in the utilization of surgical manpower in the prepaid group appear to stem from: 1) restriction of practice setting to a single geographic location, 2) restriction of patients to surgical patients, 3) reduced surgeon waiting time in the office, and 4) the utilization of paraprofessional personnel for selected operative assisting. These economies were achieved while the prepaid group surgeons were observed to average more time per patient visit both on rounds and in the office than the community surgeons. 相似文献
109.
Two-year disease-free survival is considered highly predictive of therapeutic success with neuroblastoma and death from neuroblastoma greater than 5 years after diagnosis is a rare event. We report of an unusual case of death from neuroblastoma 20 years after diagnosis; a literature review and discussion of this rare phenomenon of late recurrence is also included. Five additional cases of late recurrence, defined as greater than 5 years after diagnosis, were found in the literature with adequate detail to be reviewed. Advanced disease was present at diagnosis in five of six cases; three of six had disseminated disease. No age or sex differences were noted. A peculiar tencency for recurrence during the teenage years, preceded by a long disease-free interval, was also present in all cases, perhaps a reflection of maturational alterations in the immune system or hormonal changes that previously had suppressed extensive disease. This phenomenon of late recurrence in neuroblastoma, albeit rare, adds another facet to the clinical behavior of an enigmatic and therapeutically unyielding childhood tumor. 相似文献
110.