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BACKGROUND: Few reports have been made regarding the long term safety of implantable venous access devices used for the delivery of chemotherapeutic agents. The authors' goals were to determine the frequency of complications in patients receiving chemotherapy with these devices; to determine whether complications were associated with the mode of chemotherapy delivery (push/bolus or infusional regimens); and to evaluate the influence of other risk factors, including home-based versus hospital-based administration. METHODS: A total of 152 oncology patients at the John L. McClellan Memorial Veterans Administration Medical Center in Little Rock, Arkansas (ages 26-81 years; mean age, 62 years), who underwent surgical placement of an Infus-a-Port (Strato, Inc., Beverly, MA) between May 1, 1992 and May 31, 1994, were evaluated retrospectively for postplacement device complications, such as infection, thrombosis, and mechanical failure. RESULTS: Twenty-seven patients experienced 1 complication each: 17 episodes of device-related sepsis, cellulitis, or fever of unknown origin; 8 episodes of thrombosis or catheter occlusion; 1 episode of drug extravasation; and 1 mechanical failure. Patient age, frequency of port accession, mode of chemotherapy delivery, tumor type, and neutropenia were evaluated as risk factors, but none was statistically significant. Complications were more frequent during the first 90 days after implantation, but they continued to occur throughout the observation period. CONCLUSIONS: Complications attributable to an implantable venous access device were infrequent in this patient population. No differences in complications for patients receiving home-based versus hospital-based chemotherapy administration were noted, opening the possibility of significant time and cost savings with home treatment.  相似文献   
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108 patient were operated on the Neurosurgical Department of the Military Clinical Hospital in Wroc?aw since 1989 till 1991. The stability of the lumbar spine after hemilaminectomy and laminectomy with disc excision and interbody fusion was analysed. The period after operation ranged from 6 months to 2 years. Signs of clinical and radiological instability were the base of the study. Respective segmental motions in maximal ante- and retroflexion were calculated. Horizontal intercorporal dislocation was assessed. No signs of instability where found in the analysed material. The results after laminectomy and hemilaminectomy were similar. The failures were not caused by instability.  相似文献   
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The fall in transepithelial electrical resistance which accompanies aldosterone stimulation of short-circuit current (Isc) in toad urinary bladder has been studied further to evaluate the possible causal role of this response in hormonal stimulation of Na+ transport. A steady-state change in tissue conductance was found to depend upon both the simultaneous stimulation of transport by the steroid and the metabolic state of the tissue. Changes in metabolic state alone did not alter resistance. A sustained increase in Na+ transport, dependent on pretreatment with aldosterone and elicited by addition of glucose, could be obtained without a sustained decrease in resistance. Amiloride, an inhibitor of Na+ uptake, produced changes in Isc that were linearly correlated with its effects on tissue conductance. On the basis of the conductance-Isc relationship with amiloride, the Isc response to aldosterone was about two-fold higher than would be predicted from its effects on conductance alone. Despite the apparent lack of a simple quantitative dependence of the change in Isc on the change in conductance when the response is fully developed, the results suggest that conductance changes may mediate the initial or early stage of the response.  相似文献   
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