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Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献
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In seven patients (mean age 22 years) with injuries of the pelvic ring, the rupture of the symphysis was treated by polydioxanone ligaments. Complete rupture of the ileosacral joint was treated twice by additional external fixation, twice a compression screw osteosynthesis was applied. Incomplete iliosacral rupture in another three cases was not operated. Patients were treated functionally without signs of loosening or instability. After a control examination after 5 months all patients were free of symptoms in the area of the symphysis. Infection of the operation area did not accur. In our opinion the advantages of this method are simple operative technique, reduced risk of infection and no need for removal of metallic implants. Our excellent initial experience with synthetic PDS ligaments in operative treatment of symphysis ruptur seem to justify its application for other injuries like iliosacral or acromioclavicular rupture. 相似文献
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E J Kohlberger J R?decke J Waninger R Salm G Ruf H Walz 《Helvetica chirurgica acta》1990,57(1):157-160
The extracorporeal piezoelectric lithotripsy (EPL) is a new method for non-operative therapy of symptomatic gallbladder and problematic bile duct stones. The rare intrahepatic calculi were similarly disintegrated. Best results were reached with EPL as adjuvant measure or combined with oral cheno- and ursodeoxycholic acid therapy. EPL compared to other lithotripsy techniques is performed without any analgesia. That means advantage and patient's benefit. 相似文献
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导数光谱系数倍率法测定多组分体系感冒清胶囊中盐酸吗啉胍的含量 总被引:1,自引:0,他引:1
This paper provides a basic principle and experimental technique of derivative signal multiplier spectrophotometry in multicomponent mixture. A microcomputer was used to process the spectral data measured on a manual spectrophotometer (UV-7520) for the determination of moroxydine hydrochloride in Gan Mao Qing capsules. Quantitative analysis of multicomponent mixture can be done without sample separation. The selection of optimal wavelength pairs is performed through the program with a computer. The method needs no special spectrophotometer and is simple, rapid and easy to operate. The mean recovery was 99.98 +/- 0.53% (n = 12). 相似文献
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Requirement for binding of catalytically active factor VIIa in tissue factor-dependent experimental metastasis. 总被引:26,自引:2,他引:24 下载免费PDF全文
Tissue factor (TF), the initiating cell surface receptor of the coagulation cascade, plays important roles in embryogenesis, angiogenesis, and tumor cell metastasis. It is controversial whether proteolytic function of TF complexed with its serine protease ligand VIIa is required for metastatic tumor dissemination. We show here in a model for TF-dependent experimental hematogenous metastasis, that TF supports metastasis by both proteolytic activity of the TF-VIIa complex and currently undefined functions of the cytoplasmic domain. We demonstrate that ligand binding of VIIa to TF is required for metastasis. Antimetastatic properties of covalently inactivated VIIa provide evidence that ligand binding is insufficient per se to support metastasis, emphasizing that proteolytic activity is necessary for the metastatic process. Ala or Asp mutations of cytoplasmic serine residues were introduced to preclude or mimic phosphorylation. In vivo analysis of these mutants suggests that local protease generation on the tumor cell surface does not serve simply to activate the cytoplasmic domain of TF by serine phosphorylation. Thus, extracellular functions of the catalytically active TF-VIIa complex cooperate with specific functions of the TF cytoplasmic domain to support the complex process of hematogenous tumor cell dissemination. 相似文献
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