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51.
52.
The tax exemption for not-for-profit hospitals has been subject to many recent challenges, in part related to concerns over whether these hospitals provide sufficient levels of community benefits to merit tax exemption. Computing the value of community benefits for California hospitals as the sum of uncompensated care, education and research, net income, money-losing services, and price discounts from for-profit hospitals reveals that 20 to 80 percent of hospitals would have met various recommended community benefits standards. There is a clear need for hospitals and their communities to establish dialogues on what levels of community benefits are appropriate.  相似文献   
53.
Purpose: To determine the mechanisms of vitreous changes during ocular inflammation. Methods: We investigated vitreous changes, with special emphasis on collagen, in an experimental model of ocular inflammation induced by intravitreal injection of endotoxin (Escherichia coli) in rabbits. Results: Inflammation caused gel contraction and loss of elasticity, accompanied by release of a water-like liquid from the gel, and increases in the amount of insoluble material and highmolecular-weight components of vitreous collagen, presumably due to extensive cross-links of the collagen molecules. Those changes were partially inhibited by intravitreal injection of superoxide dismutase. Conclusions: The crosslinks of vitreous collagen may promote vitreous gel contraction and release of a water-like liquid from the gel. Superoxide anion may play a role in this process.  相似文献   
54.
To assess the impact of surgical stimulation on regulation of ventilation in anaesthetized man, we measured ventilation and the ventilatory responses to either hyperoxic hypercapnia or to isocapnic hypoxaemia in fifteen subjects anaesthetized with enflurane 1.1 MAC, just prior to and then during a surgical procedure. Anaesthesia alone reduced ventilation, increased Paco2 decreased the response to carbon dioxide and virtually abolished the response to hypoxaemia. The addition of operation at the same level of anaesthesia augmented ventilation and reduced Paco2 but did not improve the anaesthesia-induced impairment of the responses to hypercarbia and hypoxaemia. Over the range of PCO2 and PO2, values studied, the effects of surgery were constant and independent of chemical drive. A.M. Lam, M.D., Resident; J.L. Clement, R.N.; R.L. Knill, M.D., F.R.C.P.(C), Associate Professor; Department of Anaesthesia, University Hospital, University of Western Ontario, London, Canada. This work was supported by the Medical Research Council of Canada, Development Grant 150. Address reprint requests to Dr. R.L. Knill, Department of Anaesthesia, University Hospital, 339 Windermere Road, London, Ontario, Canada, N6A 5A5.  相似文献   
55.
Fibrosarcoma is a rare tumour in children. The potential of malignancy has been questioned. We present three cases of fibrosarcoma in children. The follow-up periods range from 10 to 37 years. The first patient had pulmonary metastases at the time of diagnosis in 1958. The primary tumour in fossa ischio-rectalis was resected in 1960. Lung metastases were resected in 1960 and 1989. Radiotherapy was given in 1992. He is still alive with metastases 37 years after the first manifestation of disease. The second patient had a primary tumour and several local recurrences in the mandible. He is alive without evidence of disease 4 years after resection of pulmonary metastases and 21 years after resection of the primary tumour. The third patient has no signs of recurrence or metastasic spread 10 years after a wide excision of subcutanous tumours of the left upper arm. The cases demonstrate a special tumour-entity of low-grade malignancy, which show a good prognosis and a wide spectrum of biological behaviour.  相似文献   
56.
Between 1984 and 1996, the authors performed 499 liver transplants in 416 children less than 15 years old. The overall patient survival at 10 years was 76.5%. It was 71.3% for the 209 children grafted in 1984–1990; 78.5% for biliary atresia (n =?286), 87.3% for metabolic diseases (n?=?59), and 72.7% for acute liver failure (n?=?22). The 5-year survival was 73.6% for the 209 children grafted in 1984–1990 and 85% for the 206 grafted in 1991–1996. Scarcity of size-matched donors led to the development of innovative techniques: 174 children who electively received a reduced liver as a first graft in our center had a 5-year survival of 76% while 168 who received a full-size graft had a survival of 85% (NS). Results of the European Split Liver Registry showed 6-month graft survival similar to results obtained with full-size grafts collected by the European Liver Transplant Registry. Extensive use of these techniques allowed the mortality while waiting to be reduced from 16.5% in 1984–1990 to 10% in 1991–1992. It rose again to 17% in 1993, leading the authors to develop a program of living related liver transplantation (LRLT). The legal and ethical aspects are analyzed. Between July 1993 and October 1997, the authors performed 53 LRLTs with 90% survival. In elective cases, a detailed analysis was made of the 45 children listed for LRLT between July 1993 and March 1997 and the 79 registered on the cadaveric waiting list during the same period. Mortality while waiting was 2% and 14.5% for the LRLT and cadaveric lists, respectively. The retransplantation rate was 4.6% and 16.1% for LRLT and cadaveric transplants, respectively. Overall post-transplant survival was 88% and 82% for children who received a LRLT or a cadaveric graft, respectively. Overall survival from the date of registration was 86% and 70% (P?<?0.05) for LRLT or cadaveric LT respectively. The 2-year post-transplant survival in children less than 1?year of age at transplantation was 88.8% and 80.3% with a LRLT or cadaveric graft, respectively; patient survival after 3 months post-transplant was 95.8% and 91.9% for stable children waiting at home, 93.7% and 93.7% in children hospitalized for complications of their disease, and 89.5% and 77.7% for children hospitalized in an intensive care unit at the time of transplantation for children who received a LRLT or cadaveric graft, respectively. It is concluded that LRLT seems to be justified for multidisciplinary teams having a large experience with reduced and split liver grafting.  相似文献   
57.
Studies utilizing the expression of Fos protein as a marker of neuronal activation have revealed that pain of deep somatic or visceral origin selectively activates the ventrolateral periaqueductal gray (vlPAG). Previous anatomical tracing studies revealed that spinal afferents to the vlPAG arose from the superficial and deep dorsal horn and nucleus of the dorsolateral funiculus at all spinal segmental levels, with approximately 50% of vlPAG-projecting spinal neurons found within the upper cervical spinal cord. This study utilized detection of Fos protein to determine the specific populations of vlPAG-projecting spinal neurons activated by noxious deep somatic or noxious visceral stimulation. Pain of cardiac or peritoneal (i.e., visceral) origin activated neurons in the superficial and deep dorsal horn and nucleus of the dorsolateral funiculus of the thoracic cord, whereas pain of hindlimb (i.e., deep somatic) origin activated neurons in the same laminar regions but in the lumbosacral cord. Each of these deep noxious manipulations also activated neurons in the superficial and deep dorsal horn and nucleus of the dorsolateral funiculus of the upper cervical spinal cord. In a second set of experiments, the combination of retrograde tracing and Fos immunohistochemistry revealed that vlPAG-projecting spinal neurons activated by deep somatic pain were located in both the upper cervical and lumbosacral cord, whereas those activated by visceral pain were restricted to the thoracic spinal cord. Thus pain arising from visceral versus deep somatic body regions influences neural activity within the vlPAG via distinct spinal pathways. The findings also highlight the potential significance of the upper cervical cord in integrating pain arising from deep structures throughout the body.  相似文献   
58.
59.
In brief: Chronic compartment syndrome (CCS) of the leg is a recently recognized cause of recurrent leg pain in the exercising patient. Apart from rest, the only effective treatment is fasciotomy. This study reviews 39 fasciotomies that were performed on 16 patients with clinically determined CSS. Fourteen (88%) of the patients returned to full activity with few or no residual complaints. These results indicate that clinically identified features can distinguish CCS from other forms of recurrent leg pain. Compartment pressure measurements taken during exercise can confirm the diagnosis of CCS and determine the need for fasciotomy.  相似文献   
60.
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