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81.
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Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images.  相似文献   
84.
Tsai  LH; White  L; Raines  E; Ross  R; Smith  RG; Cushley  W; Ozanne  B 《Blood》1994,83(1):51-55
Platelet-derived growth factors (PDGF) are potent regulators of cell proliferation. The three isoforms of PDGF AA, AB, and BB are encoded by two genes: PDGF A and PDGF B. The v-sis oncogene is homologous to the PDGF-B gene. v-sis can transform cells that express the appropriate PDGF receptors. Two different types of receptors, PDGF-alpha and PDGF- beta, also encoded by two genes, have been identified. We show that two cell lines. SMS-SB and NALM-6, both derived from pre-B-cell acute lymphocytic leukemias, express the PDGF-A chain gene, and one of them, SMS-SB, releases PDGF-A chains into the media. The SMS-SB cells also express the PDGF-beta receptor, whereas NALM-6 cells express the PDGF- alpha receptor and bind PDGF. This extends the possible targets for PDGF to the B-cell lineage lymphocytes.  相似文献   
85.
胃复安引起过敏性荨麻疹1例   总被引:1,自引:0,他引:1  
1 病例报告 男 ,2 4岁 ,因晨起饮冷开水后 ,阵发性上腹痛伴恶心 1h,呕吐 1次来就诊 ,其间无腹泻 .既往无眩晕及肝肾疾病史 .查体 :T36 .8℃ ,HR79次· min- 1 ,BP14.1/10 .2 k Pa,一般状况可 ,咽、扁桃体不充血 ,心肺未见异常 ,腹部平坦 ,未见明显肠型及蠕波 ,左上腹深压痛 ,无肌卫及反跳收稿日期 :2 0 0 0 -0 7-2 1; 修回日期 :2 0 0 0 -0 8-2 3作者简介 :丁向清 (196 8-) ,男 (汉族 ) ,湖北省应城市人 .主治医师 .Tel.(0 431) 79710 16 Ext. 6 6 5 12痛 ,肝脾未及 ,肠鸣音略亢进无气过水声 ,肾区无叩痛 ,胸腹透未见异常 ,WBC 5 .3…  相似文献   
86.
The principal objective of this paper is to provide health practitioners with information on the positive aspects of shorter stature for use in counseling short children with poor self-images. Another objective is to provide information on the physical capabilities, health potential and psychosocial characteristics of shorter stature as a baseline for deciding whether a healthy short child should receive growth hormone therapy. The information presented here was obtained from review of publications covering medical and nutritional research, gerontological studies, athletic performance and environmental, biological and engineering aspects of the human body. It was found that the popular belief in the superiority of tall stature is based primarily on social bias rather than on a scientific foundation. Studies indicating that taller people are healthier or more productive than shorter ones have ignored a wide range of evidence that shorter people are highly creative, productive, long-lived, athletic and better for the environment. The authors urge medical and scientific professionals to consider the many advantages of shorter stature in terms of health, social and environmental benefits.  相似文献   
87.
Corrosion of lead sheet used for structural radiation protection in the Princess Alexandra Hospital radiology department has been identified. The corrosion is thought to have been caused by organic acid vapours released from oregon timber wall panelling. Non-destructive testing (NDT) and X-ray transmission measurements were used to define the extent and severity of damage, and subsequently to provide the data necessary for estimation of staff and public radiation doses. Although radiation dose limits have not been exceeded, corrective actions including structural modifications and staff information sessions have been undertaken.  相似文献   
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89.
Localized renal cell carcinoma (RCC) responds well to surgery. Patients often question how long they have to be on surveillance after their surgery. Several follow-up patterns have been described in the literature. Until 2009, no published established Canadian guidelines existed to assist Canadian health-care practitioners in the surveillance of these patients. We present 3 cases of RCC that recurred 10 years or longer after the initial nephrectomy. These cases emphasize the need for careful long-term follow-up, as recommended in the Canadian Urological Association guidelines. We also discuss the optimism of prolonged disease survival in the era of novel therapeutic agents that target angiogenesis.  相似文献   
90.
Elevated levels of intact parathyroid hormone (iPTH) are not uncommon after renal transplantation, and this disturbance may affect renal allograft function. This study investigated whether iPTH levels were related to histopathological findings of acute rejection in kidney graft biopsies. Thirty-eight renal transplant recipients (29 males, nine females; mean age 29.5±10.3years) were studied. Renal allograft biopsy was performed in each case to investigate increased creatinine levels. Lymphocyte and macrophage infiltration of the interstitium was evaluated immunohistochemically with monoclonal antibodies to CD3 and CD68. Expression of HLA-DR and fibronectin were also studied. The proportion of interstitial cell staining was graded semiquantitatively. Serum calcium, phosphorus and iPTH levels before and after the renal transplantation were compared. Patients were grouped according to their stabilized iPTH levels at 3 months post-transplantation. Group I ( n =13) exhibited persistently elevated iPTH levels (levels elevated since surgery), and Group II ( n =25) showed persistently low-normal iPTH levels. The mean age of the Group I patients was significantly lower, and their serum calcium levels post-transplantation were significantly higher than those in Group II ( P =0.02 and P =0.03, respectively). Persistent elevation of iPTH was strongly associated with interstitial T-cell density, macrophage density, and glomerular fibronectin expression in the renal allograft biopsies ( P <0.05). Also, the time to fibrosis was significantly shorter in Group I ( P =0.02). The study revealed that PTH has a potent immunomodulatory effect, and that persistent hyperparathyroidism has a significant impact on renal allograft outcome. The data indicate that the serum iPTH level is a valuable indicator of immune response, and that regular monitoring of serum iPTH levels is essential after renal transplantation.  相似文献   
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