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991.
992.
A case is discussed of the use of medical images from the internet to support claims of injury. There were several inconsistencies in both history and examination even prior to the presentation of the specimen radiograph from the internet. Clinicians are advised to be vigilant, to question histories that do not match with examination findings, to ensure that all radiographs are adequately labelled with patient-specific information and to look for radiographic inconsistencies such as the presence or absence of accessory ossicles.  相似文献   
993.
The Department of Defense issued a Request for Proposal (RFP) for its next generation Picture Archiving and Communications System in January of 1997. The RFP was titled Digital Imaging Network-Picture Archiving and Communications System (DIN-PACS). Benchmark testing of the proposed vendors' systems occurred during the summer of 1997. This article highlights the methods for test material and test system organization, the major areas tested, and conduct of actual testing. Department of Defense and contract personnel wrote test procedures for benchmark testing based on the important features of the DIN-PACS Request for Proposal. Identical testing was performed with each vendor's system. The Digital Imaging and Communications in Medicine (DICOM) standard images used for the Benchmark Testing included all modalities. The images were verified as being DICOM standard compliant by the Mallinckrodt Institute of Radiology, Electronic Radiology Laboratory. The Johns Hopkins University Applied Physics Laboratory prepared the Unix-based server for the DICOM images and operated it during testing. The server was loaded with the images and shipped to each vendor's facility for on-site testing. The Defense Supply Center, Philadelphia (DSCP), the Department of Defense agency managing the DIN-PACS contract, provided representatives at each vendor site to ensure all tests were performed equitably and without bias. Each vendor's system was evaluated in the following nine major areas: DICOM Compliance; System Storage and Archive of Images; Network Performance; Workstation Performance; Radiology Information System Performance; Composite Health Care System/Health Level 7 communications standard Interface Performance; Teleradiology Performance; Quality Control; and Failover Functionality. These major sections were subdivided into workable test procedures and were then scored. A combined score for each section was compiled from this data. The names of the involved vendors and the scoring for each is contract sensitive and therefore can not be discussed. All of the vendors that underwent the benchmark testing did well. There was no one vendor that was markedly superior or inferior. There was a typical bell shaped curve of abilities. Each vendor had their own strong points and weaknesses. A standardized benchmark protocol and testing system for PACS architectures would be of great value to all agencies planning to purchase a PACS. This added information would assure the purchased system meets the needed functional requirements as outlined by the purchasers PACS Request for Proposal.  相似文献   
994.
Neural tube defects are a common, complex disorder with genetic and environmental components to risk. We investigated the previously reported interaction between homozygosity for the thermolabile variant at the methylenetetrahydrofolate reductase and heterozygosity for the 844ins68 allele at the cystathionine beta-synthase loci in cases with lumbosacral myelomeningocele and their parents. Using control allele frequencies from our sample pooled with those published in the literature, we confirm a marginally significant interaction at these two loci. This finding suggests that additional, larger studies are warranted to investigate this possible interaction in more detail.  相似文献   
995.
996.
BACKGROUND: Cosmetic results after skin surgery are a key component of patient satisfaction and self-image. Various lasers have been used to attempt scar improvement, without consistent results. The optimal time to initiate laser treatment has not been determined. A recent study using a noncooled 585 nm pulsed dye laser starting on the day of suture removal demonstrated substantial improvement in scar appearance. OBJECTIVE: To determine the efficacy of the 595 nm cryogen-cooled pulsed dye laser in the treatment of surgical scars starting on the day of suture removal. METHODS: Sixteen patients with postoperative linear scars of greater than 2 cm were treated three times at 4- to 8-week intervals with a 595 nm cryogen-cooled pulsed dye laser. All patients had Fitzpatrick skin types I to IV. Each scar was divided at the midline into two fields, with half receiving treatment using a 7 mm spot size at 1.5 ms with 8 J/cm2 and a 30 ms spray duration with a 10 ms delay. The other half was not treated. Scars were evaluated for pigmentation, vascularity, pliability, and height by a blinded examiner using the Vancouver Scar Scale (VSS). In addition, the same blinded examiner evaluated the cosmetic appearance using a scale from 0 (worst) to 10 (best) prior to the second treatment and 1 month after the final treatment. RESULT: SThe average sum of all parameters in the VSS showed significant improvement from 1-month post-treatment to the final evaluation of 60% compared with the control of -3%. Also, scars in the treated portions scored an average of 2 points higher in the overall cosmetic appearance by the same blinded examiner based on a scale of 0 (worst) to 10 (best). Among the individual parameters in the VSS, the most significant improvements were found in vascularity and pliability. CONCLUSION: The cryogen-cooled 595 nm pulsed dye laser is a safe and effective option to improve the cosmetic appearance of surgical scars in skin types I to IV starting on the day of suture removal.  相似文献   
997.
2004年12月26日,苏门答腊外海的一次海底地震引发的海啸袭击了东南亚沿海大部分地区,包括拥有大量游客的泰国旅游胜地普吉岛。最初报道称约有100人死亡,300人受伤,后续报道中死亡和受伤的人数急剧上升。得到最初消息后,德国空军空运司令部立即做好了用空客A-310MRT医疗后送飞机  相似文献   
998.
P-selectin expressed on the surface of endothelium mediates leukocyte adhesion in vitro and rolling in vivo. Several inducers of cell-surface P-selectin expression on endothelial cells (EC) have previously been identified, all of which yield transient cell-surface expression of P- selectin lasting minutes to a few hours. We now show that a T- lymphocyte product, interleukin-3 (IL-3), stimulates the long-term endothelial cells (HUVEC). IL-3 induced cell-surface P-selectin expression in two phases. An initial peak at 10 minutes was followed by a prolonged upregulation beginning 16 hours after IL-3 addition and lasting at least 4 days. The level of P-selectin expression induced by IL-3 added for 48 hours was similar to that induced by treatment of HUVEC for 10 minutes with thrombin, and the effect of adding IL-3 for 48 hours followed by thrombin for 10 minutes was additive. Induction of cell-surface P-selectin expression by IL-3 was blocked by pretreatment of EC with a blocking monoclonal antibody against the IL-3 receptor alpha-chain. Lipopolysaccharide (LPS), tumor necrosis factor alpha (TNF alpha) and a mutant form of IL-3 with decreased potency did not induce cell-surface P-selectin expression after 48 hours' incubation with HUVEC, suggesting that the effect was specific to IL-3. The increase in cell-surface P-selectin expression occurring after 16 hours of incubation with IL-3 was accompanied by a similar prolonged increase in the steady-state mRNA level that was not observed at 10 minutes after IL-3 addition. As T-lymphocyte infiltration is a hallmark of chronic inflammation, our observations suggest that the secretion of IL-3 by T lymphocytes may serve to maintain the inflammatory state during chronic inflammation.  相似文献   
999.
1000.
The cutaneous form of polyarteritis nodosa in children is extremely rare. Findings are usually limited to the skin, muscles and joints. It has a benign but often chronic course. We describe an 8-y-old girl with cutaneous PAN, with extensive livedo reticularis on lower and upper extremities, tender subcutaneous nodules, arthralgia and right ankle swelling. Skin biopsy revealed vasculitis of small and medium-sized blood vessels characterized by fibrinoid necrosis. The use of prednisolone resulted in clinical improvement initially, but recurrence occurred during tapering. She showed marked improvement with additional high dose methyl prednisolone monthly.  相似文献   
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