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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
M. Fujita J. Tajima T. Nakagawa S. Abo A. Kinomura F. Pszti M. Takai R. Schork L. Frey H. Ryssel 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2002,190(1-4):26-33
A rapid shrinkage in the minimum feature size of integrated circuits requires analysis of dopants in their shallow source–drain and their extensions with an enhanced depth resolution. Rutherford backscattering spectroscopy (RBS) combining a medium-energy He ion beam with a detector of improved energy resolution should meet the requirement of a depth resolution better than 5 nm at a depth of 10–20 nm in the next 10 years. A toroidal electrostatic analyzer of 4×10−3 energy resolution has been used to detect the scattered ions of a medium-energy He ion beam. Five keV As+ implanted Si or SiO2 samples were measured. Depth profiling results using the above technique are compared with those of glancing-angle RBS by MeV energy He ions. Limitations in the energy resolution due to various energy-spread contributions have been clarified. 相似文献
972.
The various complex mathematical transformations previously proposed for eliminating methodological errors of multicolor radiation pyrometry are mainly reduced to the determination of such combinations of wavelengths or corrections of registered brightness for the spectral distribution of the radiating capacity of the object being thermometered at which its equivalent radiating capacity is equal to unity. Mathematical formulas of the determining parameters of multicolor pyrometry of radiation have been obtained. Engineering techniques for calculating the critical values of the determining and adjustable parameters at which the application of multicolor optical thermometry is excluded because of large errors have been developed. Algorithms of a priori and a posteriori calibration systems of multicolor pyrometry of radiation of objects with practically any spectral distribution of the radiating capacity are proposed. 相似文献
973.
F. H. Wittmann 《Sadhana》2002,27(4):413-423
The crack path through composite materials such as concrete depends on the mechanical interaction of inclusions with the cement-based matrix. Fracture energy depends on the deviations of a real crack from an idealized crack plane. FRACTURE energy and strain softening of normal, high strength, and self-compacting concrete have been determined by means of the wedge splitting test. In applying the numerical model called “numerical concrete” crack formation in normal and high strength concrete is simulated. Characteristic differences of the fracture process can be outlined. Finally results obtained are applied to predict shrinkage cracking under different boundary conditions. Crack formation of high strength concrete has to be seriously controlled in order to achieve the necessary durability of concrete structures. 相似文献
974.
F Hau 《Canadian Metallurgical Quarterly》1993,36(3):297-304
PURPOSE: To determine the efficacy, dose-response relationship, and safety of 30, 60, and 90 mg of a single intravenous dose of an aminobisphosphonate, pamidronate (APD), for the treatment of moderate to severe hypercalcemia of malignancy. PATIENTS AND METHODS: Patients with histologically proven cancer and a corrected serum calcium level of at least 12.0 mg/dL after 48 hours of normal saline hydration were enrolled in a double-blind, multicenter, randomized clinical trial. Pamidronate in 30-, 60-, or 90-mg doses was administered as a single 24-hour infusion. Serum calcium corrected for albumin, urine hydroxyproline, and calcium excretion, and serum parathyroid hormone (PTH) (1-84) were determined before and after pamidronate therapy. RESULTS: Thirty-two men and 18 women entered the study. A dose-response relationship for normalization of corrected serum calcium was seen after pamidronate administration. Corrected serum calcium normalized in 40% of patients who received 30 mg, in 61% of patients who received 60 mg, and in 100% of patients who received 90 mg of pamidronate. The decline in the serum calcium level was associated with decreased osteoclastic skeletal resorption evidenced by a decrease in urine calcium and hydroxyproline excretion. Among those with a normalized corrected serum calcium level, the mean (median) duration of normalization of the corrected serum calcium value was 9.2 (4), 13.3 (5), and 10.8 (6) days in the 30-, 60-, and 90-mg treatment groups, respectively. The response of hypercalcemia to pamidronate was not significantly influenced by the presence of skeletal metastases. PTH 1-84, suppressed in patients on entry into this study, increased to a greater extent in those patients with osteolytic skeletal metastases compared with those with humoral hypercalcemia of malignancy. Clinical improvement, including improved mental status and decreased anorexia, accompanied the decline in the corrected serum calcium level in all three treatment groups. Side effects included low-grade fever, asymptomatic hypocalcemia, hypomagnesemia, and hypophosphatemia. CONCLUSIONS: A single-dose infusion of 60 to 90 mg of pamidronate was highly effective and well tolerated and normalized corrected serum calcium in nearly all patients (61% to 100%) with hypercalcemia of malignancy. 相似文献
975.
M Miranda F Amicarelli AR Volpe A Poma L Masciocco M Carmignani 《Canadian Metallurgical Quarterly》1993,24(6):1319-1322
1. The present paper reports the effects of liposome-entrapped tyrosinase (EC 1.14.18.1. L-Tyrosine, L-3,4-dihydroxyphenylalanine: oxygen oxidoreductase) infusion on the catecholamine contents of rat plasma. The actions of liposomes and free tyrosinase have also been investigated. 2. From the experiments, evidence has been obtained that liposome-entrapped tyrosinase is able to affect specifically L-3,4-dihydroxyphenylalanine (L-DOPA) levels which increase dramatically. 3. The possible use of liposome-entrapped tyrosinase to raise L-DOPA levels in catecholamine related disorders is discussed. 4. Liposomes without tyrosinase provoke no significant changes of catecholamine or L-DOPA levels while free tyrosinase does induce a change but in a less constant fashion than the liposome-entrapped enzyme. 相似文献
976.
M Loscertales Abril F Jaldo Alba E Díaz Lucas E Narbona López A Ruiz Extremera E Ocete Hita JA Molina Font 《Canadian Metallurgical Quarterly》1993,39(4):339-342
Four patients who complained of symptoms and signs compatible with biliary tract disease and in whom the diagnosis of gallbladder (three cases) and common bile duct ascariasis (one case) was made sonographically are reported. In two patients with gallbladder ascariasis, cholecystectomy corroborated the presence of the round-worms, and was curative. The third patient was a pregnant woman (32nd gestational week) who took piperazine citrate, and a second sonogram performed 29 days later was completely normal. The fourth patient with common bile duct ascariasis underwent choledochotomy with extraction of one ascaris lumbricoides from the common duct, and a T tube was left in place for 15 days. All patients received antiparasitics and had a favorable outcome. Ultrasonography is an important noninvasive diagnostic procedure in the work-up of these patients, who usually describe a clinical picture suggesting gallstone disease: this is especially true in the presence of pregnancy. 相似文献
977.
978.
CB Henk S Grampp P Wiesbauer A Zoubek F Kainberger M Breitenseher GH Mostbeck H Imhof 《Canadian Metallurgical Quarterly》1998,38(6):509-522
Ewing's sarcoma is a highly malignant neoplasm of the bone whose origin is still uncertain. A strong relationship exists between Ewing's sarcoma and tumors of neural origin (Ewing family of tumors). Ewing's sarcoma must be distinguished from other round-cell tumors like lymphoma and neuroblastoma and also must be differentiated from osteogenic sarcomas. On plain radiographs, Ewing's sarcoma appears as a lytic or mixed lytic-sclerotic, rarely as predominantly sclerotic lesion with margins Lodwick grade III. It is located primarily in the diaphyseal and metadiaphyseal regions of the long bones of the lower extremities. A large soft tissue tumor is usually present. Magnetic resonance imaging is the imaging modality of choice to evaluate the extent of the primary lesion, to monitor the response to neoadjuvant chemotherapy and to follow up non-resected Ewing's sarcomas. Bone scintigraphy is necessary to detect skeletal metastasis, and 201thallium scanning has been shown to be sensitive in the monitoring of treatment response. Today, computed tomography is not longer used to image the tumor site; however, spiral CT of the lungs plays a central role as a staging and follow-up tool. 相似文献
979.
F Soubrier 《Canadian Metallurgical Quarterly》1996,57(3):155-159
In this study, we investigated the immunoreactivity of the Technicon Immuno 1 PSA assay, a monoclonal-polyclonal sandwich immunoassay, with free and ACT-complexed PSA. Assay calibrators prepared with free PSA (standard Immuno 1 calibrators) and calibrators consisting of 90% ACT-complexed and 10% free PSA (90:10 calibrators) yielded virtually identical PSA recoveries at all concentrations tested. Concentrations of total PSA at approximately 4 and 10 ng/mL, prepared in varying ratios of free PSA to PSA-ACT complex, recovered from 92-104% at 4 ng/mL and from 98-102% at 10 ng/mL. Additionally, an excellent correlation of serum total PSA values from a panel of 40 prostatic cancer patient samples was obtained using calibration curves generated with the standard Immuno 1 calibrators or the 90:10 calibrators. These results demonstrate that the Technicon Immuno 1 PSA assay measures free and ACT-complexed PSA on an equal molar basis. 相似文献
980.
Y Kato S Yamaguchi H Sano Y Ogura K Katada G Takeshita F Imai T Kanno M Abe 《Canadian Metallurgical Quarterly》1996,39(4):113-115
A patient with subacute bacterial endocarditis and a peripheral mycotic aneurysm is presented. We used a combined multi-slice surface anatomy scanning (SAS) and contrast-enhanced MR angiography image to determine the exact location of the small lesion by applying a skin marker on the scalp and visualizing the relationship of the marker to the brain surface structures and to the lesion. This technique was useful for the removal of a small peripheral aneurysm using only a limited craniotomy. 相似文献