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Fatal and non-fatal stingray envenomation   总被引:2,自引:0,他引:2  
A fatality occurred in a previously healthy 12-year-old boy after a penetrating chest injury from a stingray barb. The injury occurred under freak circumstances. Death was a result of cardiac tamponade which was secondary to venom-induced, localized myocardial necrosis and spontaneous perforation, six days after the direct penetration of the right ventricle by the barb. Three other cases of less serious stingray envenomation are described which illustrate the significant localized morbidity that may occur without immediate wound exploration and toilet after adequate anaesthesia. We also report a study of a series of 100 minor stingray envenomations which, when treated, resulted in no morbidity. It is possible that local infiltration with 1% plain lignocaine may have a direct counteraction against stingray venom that remains in the wound area. Stingray venom has insidious, but powerful, localized tissue necrosing properties in humans.  相似文献   
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This study empirically examines the practices of non-physician providers (NPPs) within three large competitive health maintenance organizations (HMOs), as well as the physicians' and NPPs' views regarding the ideal role of NPPs. These roles are compared with NPP delegation patterns incorporated in the modeling methodology developed by the Graduate Medical Education National Advisory Committee (GMENAC). GMENAC recommended relatively high levels of delegation by physicians to NPPs. One of the HMO sites made use of NPPs at rates even higher than GMENAC's national ideals, while the rates at the other two were lower. The normative ideals for pediatric NPPs developed at each HMO were consistently higher than their actual roles. Concerns with acceptance and the role of NPPs are clearly no longer issues. Instead, the limits on NPP involvement appear to relate to considerations of costs, availability, and the increasing numbers of physicians competing for similar opportunities.  相似文献   
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Emphysematous pyelonephritis is a severe life-threatening infection which continues to carry significant morbidity and mortality. We present a case recently managed at our institution by laparoscopic nephrectomy. The patient survived, and in comparison to some of the more conventionally managed patients in the literature, made an extremely speedy recovery. We would advocate this option to be seriously considered when patients are suitable and appropriately trained surgeons are available.  相似文献   
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Regulation of T cell-dependent immune responses is mediated in part by bone marrow-derived antigen presenting cells (APC) that (a) process and present antigens which engage the T cell receptor and (b) secrete cytokines that influence the threshold of T cell activation. The anterior chamber of the eye is lined by the corneal endothelium (which rests on a stroma and epithelium that is devoid of class II MHC + APC) and iris/ciliary body (which contain significant numbers of bone marrow-derived cells, one third of which are class II MHC +). When tested in vitro, these potential APCs fail to present antigens in a form that activates T cells. Moreover, iris/ciliary body cells actually suppress activation of T cells exposed to antigens on conventional APC. In addition, aqueous humor under normal circumstances contains factors (one of which is TGFB) that are potent inhibitors of antigen-driven T cell activation, but spare other aspects of T cell function. Evidence suggests that the bone marrow-derived cells in iris/ciliary body are the source of this factor. Thus, the anterior chamber contains powerful forces that can prevent induction and can suppress expression of T cell mediated immunity. It is proposed that these forces are responsible for immunologic privilege and anterior chamber associated immune deviation, and for suppressing pathologic proliferation and inflammation in the anterior segment of the eye.  相似文献   
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The effect of total-lymphoid irradiation on survival of canine pancreas and kidney allografts was studied. TLI had a marked immunosuppressive effect as measured by in vitro immune responses and reduced circulating leukocytes. Despite the changes, median graft survival times for animals treated with 800 cGy (9 days) or 1800 cGy (9.5 days) were not significantly different from untreated control animals (7 days). The addition of low-dose antithymocyte globulin (10 mg/kg/day) on post-transplant days 0, 2, 4, 6, 8, and 10 had no measurable synergistic effect. Similarly, median segmental pancreas allograft survival times after 1700-2200 cGy of TLI treatment (16.5 days) were only marginally longer than those of untreated controls (9 days). The only animal to maintain a graft for greater than 200 days was matched to the donor in mixed lymphocyte culture (MLC). This animal was able to reject a third-party skin graft after 8 days while a graft from the original donor was still surviving after 21 days when the pancreas graft failed from a chronic-type rejection. These results indicate that TLI alone or in combination with ATG will not be predictably effective as a method of prolonging allograft survival. The role of matching major histocompatibility complex antigens in TLI treatment requires clarification.  相似文献   
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Surgical services are an important part of modern health care, but providing them to isolated rural citizens is especially difficult. Public policy initiatives could influence the supply, training, and distribution of surgeons, much as they have for rural primary care providers. However, so little is known about the proper distribution of surgeons, their contribution to rural health care, and the safety of rural surgery that policy cannot be shaped with confidence. This study examined the volume and complexity of inpatient surgery in rural Washington state as a first step toward a better understanding of the current status of rural surgical services. Information about rural surgical providers was obtained through telephone interviews with administrators at Washington's 42 rural hospitals. The Washington State Department of Health's Commission Hospital Abstract Recording System (CHARS) data provided a count of the annual surgical admissions at rural hospitals. Diagnosis-related group (DRG) weights were used to measure complexity of rural surgical cases. Surgical volume varied greatly among hospitals, even among those with a similar mix of surgical providers. Many hospitals provided a limited set of basic surgical services, while some performed more complex procedures. None of these rural hospitals could be considered high volume when compared to volumes at Seattle hospitals or to research reference criteria that have assessed volume-outcome relationships for surgical procedures. Several hospitals had very low volumes for some complex procedures, raising a question about the safety of performing them. The leaders of small rural hospitals must recognize not only the fiscal and service benefits of surgical services--and these are considerable--but also the potentially adverse effect of low surgical volume on patient outcomes. Policies that encourage the proper training and distribution of surgeons, the retention of basic rural surgical services, and the rational regionalization of complex surgery are likely to enhance the convenience and safety of surgery for rural citizens.  相似文献   
10.
One possible complication in infant pneumonectomy is mediastinal shift that can fatally kink or compress airways and vessels. Rigid prostheses have been used to prevent these problems; however, they cannot be adjusted as the child grows. We report a case of expandable prosthesis implantation in a 24-day-old infant. During the 18 months postimplantation, the prosthesis was periodically injected with a saline/contrast solution to maintain the mediastinum in a midline position as the child grew. At 24-month follow-up the prosthesis was still in place, and midline position of the mediastinum maintained.  相似文献   
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