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991.
MS Ellis 《Canadian Metallurgical Quarterly》1997,149(5):151-158
The explosive growth in Managed Care Organizations as a mechanism for providing health care in the United States has generated an equal explosion in litigation and new legislation related to problems within this delivery system. Abuses have included the "gagging" of physicians from providing full disclosure of medical options for their patients, inappropriate denial of care, denial of specialty referral, false claims data, insurer insolvency, economic credentialling, deselection, financial disincentives to render care, and lack of appeal or grievance mechanisms. These issues and others have resulted in injuries to patients and damage to the patient/physician relationship. This article discusses some of the more dramatic litigated cases and endeavors to alert both physicians and patients to potential legal matters that should be considered before becoming involved within this structure. 相似文献
992.
DB Reuben M Lee JW Davis MS Eslami DG Osterweil S Melchiore NT Weintraub 《Canadian Metallurgical Quarterly》1997,12(7):450-452
This study reports the development and preliminary validation of an instrument to measure geriatrics knowledge of primary care residents. A 23-item test was developed using questions selected from the American Geriatrics Society's Geriatrics Review Syllabus. Ninety-six internal medicine and family practice residents, 14 geriatrics fellows, and 11 geriatrics faculty members participated in the study. Findings support the reliability (Cronbach's alpha = 0.66) and validity (content and "known groups") of this short test. Predictive validity and sensitivity of the test to changes in knowledge will have to be further explored as residents progress through their training. 相似文献
993.
A comparative psychophysiological analysis of anxiety disorders of a permanent and paroxysmal nature
Observation of patients with panic disorders (PD) and generalized anxious disturbances (GAD) by means of contingent negative variation (CNV) revealed that they significantly differ from healthy individuals. Anxiety, depression and autonomic dysfunction were more pronounced in such patients. Both high amplitude of early CNV component and alteration of its habituation were quite typical for patients with PA in contrast to GAD patients and healthy individuals. There were no differences in CNV indices between the healthy group and the patients with GAD. PA patients differed from GAD ones by smaller manifestation of depression, shorter duration of the disease, shorter time of reaction. The data obtained have demonstrated qualitative psychophysiologic differences between PA and GAD groups of patients. They were mostly pronounced in both amplitude of early CNV and alteration of its habituation. PA patients were characterized by an increase of excitability in brain cortex and by surplus orientation activity. The authors suppose that specific CNV pattern reflects neurodynamics of "paroxysmal brain". 相似文献
994.
SD Gertz ML Rennels MS Forbes J Kawamura T Sunaga E Nelson 《Canadian Metallurgical Quarterly》1976,45(5):514-519
The effects of temporary vascular occlusion with surgical clips on the underlying endothelial lining were studied with scanning (SEM) and transmission (TEM) electron microscopy. Twenty-five rabbits were anesthetized and both common carotid arteries exposed. A Heifetz clip was used to occlude the right carotid artery for 5, 15, and 30 minutes, and 2 hours in five animals each. The clips were removed and the vessels immediately perfused with glutaraldehyde. In five remaining animals, the right carotid arteries were occluded for 30 minutes followed by removal of the clip and resumption of blood flow for 30 minutes prior to fixation. Combined SEM and TEM examination of the endothelium of compressed segments revealed "craters" and "balloons", blebs and vacuoles, swollen mitochondria, dilated granular endoplasmic reticulum, and subendothelial edema. There were also areas of endothelial cell flattening, discontinuity, and desquamation exposing the subendothelial tissues. Following restoration of flow, platelets and fibrin were found adherent to altered endothelial cells and to exposed subendothelial tissues. Endothelial craters and balloons were also found distal and, significantly less frequently, proximal to the site of occlusion. It is suggested that antiplatelet aggregating agents may prove beneficial for the prevention of thrombus formation at the site of the clip as well as craters and balloons distal to the clip following procedures requiring temporary vascular occlusion. 相似文献
995.
GJ Griffiths KB Robinson GO Cartwright MS Mclachlan 《Canadian Metallurgical Quarterly》1976,49(578):111-117
Eighty-eight kidneys obtained at necropsy from normotensive subjects aged over 50 years were examined histologically and by post-mortem pyelography and angiography. Moderate or severe scarring was present in 50%. Its distribution and the absence of calyceal deformity make pyelonephritic scarrig unlikely. Its extent was related to the severity of change in the renal vessels, but not to age. On pyelograms, scarring was difficult to distinguish from fetal lobation. Kidneys with the most severe histological changes in the vessels tended to show the most marked angiographic distortion, though in general the two techniques examine different parts of the renal vascular bed. Total renal area and "cortical" area, measured from the angiograms, were not significantly correlated with age, thouth both tended to be smaller in older subjects. These dimensions, particularly cortical area, were significantly correlated with vascular changes, being smallest when vessels were most markedly affected. Results suggest that the loss of renal tissue which occurs in the elderly, particularly selective loss of cortex, is more closely related to events in the renal vasculature than to age itself. 相似文献
996.
A retrospective survey of 44 children with colorectal perforating injuries secondary to shrapnel and high velocity bullets is presented. Seven patients had the injury limited to the colon or rectum. All patients were operated upon within 7 hr from the their colonic wounds and 20 underwent a colostomy. Five of the patients repaired primarily had their injuries to the left side of the colon or rectum. None of the patients undergoing primary repair suffered from an anastomotic leak. The mortality rate after primary repair was 16.6% and after colostomy 10%. The mortality was significantly different in the group of patients who had additional injuries where a colostomy procedure was associated with a lower mortality rate (11% versus 21%). Shock on admission and during operation affected survival adversely in all patients. The average hospital stay of survivors was 24 days with "primary repair" and 36 days with "colostomy." 相似文献
997.
P. H. JONES BASc MS PhD FIE CPEng S. HERAT BSc MEngSc CEng MICE MIE 《Water and Environment Journal》1994,8(2):165-170
The use of cement kilns for managing solid and hazardous wastes is facilitated by the high temperature, long gas retention periods, natural alkaline environment, minimum amount of waste produced and high thermal capacity. The main benefits include energy recovery, conservation of fossil fuels, reduction in cement production costs and the use of already existing facilities.
The test burns conducted in cement kilns worldwide have demonstrated very high destruction efficiencies for most stable organic compounds, with toxic contaminants barely above the background levels.
There are several cement plants in the US and Europe presently using solid and hazardous wastes as supplementary fuel. The application of this technology in Australia has been ignored in the past. An international conference (Kilnburn'92) on the role of cement kilns in waste management was held recently in Australia and has enhanced the implementation of this technology in Australia. 相似文献
The test burns conducted in cement kilns worldwide have demonstrated very high destruction efficiencies for most stable organic compounds, with toxic contaminants barely above the background levels.
There are several cement plants in the US and Europe presently using solid and hazardous wastes as supplementary fuel. The application of this technology in Australia has been ignored in the past. An international conference (Kilnburn'92) on the role of cement kilns in waste management was held recently in Australia and has enhanced the implementation of this technology in Australia. 相似文献
998.
The Baumgartner perfusion technique was used to test the ability of rehydrated lyophilized human platelets to adhere to the thrombogenic surface of a denuded arterial vessel segment and to undergo platelet activation under conditions of high shear. Twenty preparations of washed platelets were stabilized by 1-hour or 2-hour exposure to paraformaldehyde before freeze-drying in a Virtis 600 lyophilizer. The response of these fixed-dried preparations was compared with that of non-fixed platelets in fresh citrated whole blood. The outcome of each perfusion experiment was quantified in photomicrographs by morphometric estimation of the percent area of the vessel segment covered by adherent platelets after immunofluorescent staining with monoclonal antibodies to glycoprotein Ib (CD42) or glycoprotein IIbIIIa (CD41a). Evidence of activation in nonadherent platelets was examined by flow cytometry for CD62 and GP53 expression. In addition, thromboxane B2 was measured by radioimmunoassay as an index of platelet responsiveness to activation conditions during perfusion. The percent vessel coverage observed with lyophilized platelets in recombined whole blood was somewhat less than that of platelets in fresh whole blood (39% vs 73%, respectively). In other perfusion experiments performed with non-denuded vessel segments, the percent coverage was reduced by half or more for both types of platelet preparation. Scanning electron microscopy confirmed that the lyophilized platelets did not adhere to areas of intact endothelium. Furthermore, the lyophilized platelets showed a small-but-significant rise in CD62 or CD63 activation antigen expression and generated thromboxane B2 at about one third the rate of fresh platelets in these perfusion experiments. The thromboxane generation during perfusion was inhibited in fresh or lyophilized platelet preparations by pretreatment with indomethacin or PGE-1. We interpret these data as evidence of the ability of our lyophiilized platelet preparations to respond at least partially to physiologic stimuli and to adhere to appropriate thrombogenic sites to support hemostasis. 相似文献
999.
B. R. Simon Rosser Ph.D. MPH Laura Gurak Ph.D. Keith J. Horvath Ph.D. J. Michael Oakes Ph.D. Joseph Konstan Ph.D. Gene P. Danilenko MS 《Journal of Computer-Mediated Communication》2009,14(3):602-626
This study documents our experience in designing, testing, and refining human subjects' consent protocol in 3 of the first NIH-funded online studies of HIV/STI sexual risk behavior in the USA. We considered 4 challenges primary: a) designing recruitment and enrollment procedures to ensure adequate attention to subject considerations; b) obtaining and documenting subjects' consent; c) establishing investigator credibility through investigator-participant interactions; d) enhancing confidentiality during all aspects of the study. Human consent in online studies appears more relative, continuous, inherent, tenuous, and diverse than in offline studies. Reasons for declining consent appear related to pragmatic concerns not human subjects' risks. Reordering the consent process, and short, chunked, stepwise, tailored consent procedures may enhance communicating information and documenting consent. 相似文献
1000.
Supracondylar femur fractures above a total knee replacement are rare injuries that may be challenging to treat. We present a case of an elderly woman whose supracondylar femur fracture was not deemed amenable to conventional treatment. This patient underwent fixation of her femur fracture above a total knee replacement using an Ilizarov external fixator. The fixator was removed at 10 weeks, at which time the fracture was solidly healed. At the most recent follow-up, the patient is 19 months postinjury. She is fully weight bearing without walking aids and has a knee range of motion of 0 degree to 110 degrees. 相似文献