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1.
An OUR-QGD gamma ray stereotactic body radiotherapy system (body knife), made in China, is described. According to its structure and the principle of gamma radiation revolved on a focus, the energy distribution of scattered radiation in its treatment room is calculated. The structural shielding of the wall, roof, and door for a certain treatment room is calculated according to the local radiation protection law.  相似文献   
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报告8例Wegener肉芽肿病。本组疾病的病理特点均表现为坏死性血管炎及肉芽形成。临床特点为:发热(38-40℃)、鼻塞、鼻衄、咳嗽、口腔及鼻咽部溃疡,皮下结节:X线表现为肺部多发性结节及空洞阴影,副鼻窦炎症。尿常规检查异常,诊断主要依靠病变组织活检。环磷酰胺和肾上腺皮质激素联合治疗效果显著。  相似文献   
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The hereditary characteristics of enzyme deficiency and dermatoglyphics in congenital color blindness (CCB) were studied. We propose that there is a linkage between the two loci on the X-chromosome determining CCB and glucose-6-phosphate dehydrogenase (G6PD), based on our study of a high incidence of G6PD deficiency in 156 male cases with CCB. The CCB gene is closely linked with that of G6PD deficiency from our pedigree investigations. The rise in the frequency of eight or more whorls, the low value of atd angle and the presenting rate of real palmar patterns of the thenar, hypothenar and I, areas presented the hereditary traits of congenital color blindness.  相似文献   
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Cyclic voltammetric responses are calculated for the case where the reduction of a substrate proceeds only via intramolecular electron transfer to the substrate molecule when it is bound to reduced catalyst molecules present in a single monolayer on the electrode surface. The dependences of the voltammetric responses on the equilibrium constant for the formation of the catalyst-substrate complex, the rate of its formation and the rate of intramolecular electron transfer are discussed. Procedures are described for estimating the rate constant for the intramolecular electron transfer reaction and for discriminating between mechanistic possibilities.  相似文献   
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OBJECTIVES: 1) To assess, with a peripheral magnetic resonance imaging system (pMRI), the prevalence of bony and soft tissue abnormalities in the knee joints of normal subjects, osteoarthritis (OA) patients, and individuals who have suffered an anterior cruciate ligament (ACL) rupture; and 2) to compare the prevalence among groups. METHODS: Magnetic resonance (MR) images of 28 healthy, 32 OA, and 26 ACL damaged knees were acquired with a 1.0-T pMRI system. Two radiologists graded the presence and severity of 9 MR image features: cartilage degeneration, osteophytes, subchondral cyst, bone marrow edema, meniscal abnormality, ligament integrity, loose bodies, popliteal cysts, and joint effusion. RESULTS: Ten of 28 healthy (35.7%), 24 of 26 ACL (92.3%), and all OA knees (100%) showed prevalent cartilage defects; 5 healthy (17.9%), 20 ACL (76.9%), and all OA knees (100%) had osteophytes; and 9 normal (32.1%), 21 ACL (80.8%), and 29 OA knees (90.6%) had meniscal abnormalities. One-half of the knees in the OA group (16 of 32, 50%) had subchondral cysts, and almost one-half had bone marrow edema (15 of 32, 46.9%). These features were not common in the ACL group (7.7%, and 11.5%, respectively) and were not observed in healthy knees. The OA group had the most severe cartilage defects, osteophytes, bone marrow edema, subchondral cysts, and meniscal abnormalities; the ACL group showed more severe cartilage defects, osteophytes, and meniscal abnormalities than did normal subjects. CONCLUSION: The results suggest that knees that have sustained ACL damage have OA-like reatures; most subjects (19 of 26, 73.1%) could be identified as in the early stage of OA. The prominent abnormalities present in ACL-damaged knees are cartilage defects, osteophytes, and meniscal abnormalities.  相似文献   
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