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61.
We report the imaging findings of an abdominal aggressive angiomyxoma, which communicated with the gastrointestinal tract. The literature on this rare tumor is reviewed.  相似文献   
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63.
We report 21 cases of stress injury of the distal radial growth plate-occurring in gymnasts before skeletal maturity. The injury appears to be caused by inability of the growth plate to withstand rotational and compressive forces. Our observations have confirmed that the skeletal age of gymnasts is retarded, which increases the length of time during which the epiphysis is at risk of damage.  相似文献   
64.
We describe the results of process mapping of nuclear emergency management procedures in four European countries. We find clear differences and explore these in relation to their suitability for building a shared understanding across the emergency management team of the evolving situation and a balanced appreciation of the uncertainties. Our findings indicate that there are some issues that cause concern in that the procedures may run smoothly and efficiently but they may also risk underestimating uncertainty or ignore key issues that have only been identified by a minority of experts or models. We are concerned that they do not facilitate the building of shared mental models that the literature such as that on highly reliable organisations has shown is important.  相似文献   
65.
Two-dimensional linear and contact finite element analyses were conducted of total hip arthroplasty using metal-backed, porous ingrowth acetabular components. The stress transmission characteristics from the component to the surrounding bone were given special attention. Resultant loads of 20 and 40 degrees medial of vertical were studied, and the influence of adding a metal flange to the rim of the cup was evaluated. The results indicated that when a conventional metal-backed component (without a flange) is initially implanted and subjected to normal loading, these components may experience distraction between the component and the surrounding bone at inferior sites. Compressive stresses in the superior dome cancellous bone, however, will be substantial. If complete porous ingrowth is achieved, the superior dome compressive stresses will be reduced and substantial shear stresses created. In addition, high local bone stresses were found at the component rim. If bone ingrowth is achieved only in specific locations, stress transmission will be dictated by those locations and may differ markedly from the case of complete bone ingrowth. In the event that no porous ingrowth is achieved and a fibrous layer forms around the component, the interface stresses will be similar to those calculated for the natural hip. The addition of a flange to the rim of the cup will reduce the magnitude of the radial stresses transmitted to the cancellous bone superiorly and medially by directly transferring some of the load to the lateral wall of the pelvis. The flange will also help to relieve the high local stresses that are found at the component rim.  相似文献   
66.
AIM: Our aim was to determine how the risk associated with presence of low transcutaneous oxygen tension (tcPO2) for subsequent major amputation in patients with skin ulcers or gangrene and peripheral arterial disease, compares with the risks associated with low peripheral pressures and low amplitude of pulse waves. Secondly, we determined whether combination of measurements of oxygen tension with that of the pressures or pulse wave amplitude predicts amputation better than pressure, wave or oxygen tension measurements alone. METHODS: Measurements were carried out to obtain foot tcPO2, ankle and toe pressures, pressure indices, and toe pulse wave amplitude in 75 limbs with skin lesions and arterial disease of 66 patients referred to the vascular laboratory. These variables were related to the risk of a subsequent major amputation during a median time of 4.2 years, using Cox proportional hazards model. RESULTS: Low oxygen tension was associated with increased risk of amputation (relative risks 2.16 and 2.55 for tcPO2 < or = 10 mmHg and < or = 20 mmHg, respectively, P<0.05; relative risk 2.22 for tcPO2 < or = 30 mmHg, P=0.07). The relative risks associated with cutoff values of ankle and toe pressures and pressure indices varied from 2.53 (toe < or = 20 mmHg, P<0.05) to 5.83 (ankle < or = 50 mmHg, P<0.001) and the relative risk associated with low wave amplitude (< or = 4 mm) was 3.41, P<0.01. The cutoff values of tcPO2 became insignificant when included in the models together with each pressure variable or pulse amplitude separately. In contrast, wave amplitude remained significantly associated with increased risk of amputation after controlling for each pressure variable (P<0.05). CONCLUSIONS: TcPO2 < or = 10 mmHg and < or = 20 mmHg are related significantly to increased risk of amputation in patients with skin lesions and arterial disease, but these relative risks are similar in magnitude or smaller than those associated with low cutoff values of pressures, pressure indices or pulse wave amplitude. Low wave amplitude does provide significant information in addition to peripheral pressures with respect to the risk of amputation. On the other hand, low tcPO2 does not provide significant information in addition to peripheral pressures or pulse wave amplitude.  相似文献   
67.
D C Carter 《Surgery》1992,111(6):602-603
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68.
The synthesis and structure-activity relationships of C-terminal octapeptide analogues of anaphylatoxin C5a have been studied. The introduction of hydrophobic amino acids into the N-acetylated native octapeptide (N-Ac-His-Lys-Asp-Met-Gln-Leu-Gly-Arg-OH) (1) has led to an analogue with 100 times more activity than the native octapeptide in inhibiting the binding of 125I-labeled anaphylatoxin C5a to human neutrophil membrane receptors. The observed apparent binding Ki's for the compounds (8-10) are in the range of 1-3 microM, and they possess nearly full agonist activity, despite the fact that these analogues are one-eighth or -ninth the size of the natural ligand anaphylatoxin C5a.  相似文献   
69.
70.
阳痿是男子精神上最痛苦的一种常见的性功能障碍疾病,在中医男科诸证中,占有较大的比例。细读《实用中医内科学》、部分男科学专著及公开发表的论文,运用辨证论治的方法开展对阳痿的治疗及研究,仍然是当前的主导方向。在临床实践中常常会遇到这样的病例:除了阳痿以及因阳痿产生的痛苦外,其余无任何症状,无虚象、无实象、舌脉亦然。熟记分型标准,也不能对号入座。可以说,以阳痿为主诉而就诊者,无证可辩的并非少数,辨证而后论治,无证可辨论治也就无所依凭了。通过反复阅读古代文献及现代男科学专著,结合临床经验,就阳痿的治疗谈一点体会。性功…  相似文献   
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