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41.
42.
Magnetic resonance (MR) imaging was performed on 14 patients with histologically proved osteosarcoma (mean age, 14.4 years). There was excellent correlation of intramedullary tumor extent as determined with MR imaging and pathologic examination (r = 99%). This was facilitated by the presence of a chemical shift artifact at the tumor-marrow interface on the T1-weighted images. The correlation between CT and pathologic findings was not as good (r = 84%). In a single patient, however, a 10-cm length of sclerotic bone was incorrectly interpreted as being tumor. If this case is excluded, the correlation between CT and pathologic findings improves significantly (r = 96%). T2-weighted images were optimal in demonstrating soft-tissue bulk and breach of the epiphysis or cortex. Vascular involvement was also readily defined. The T2 value of the tumor soft-tissue component decreased in patients who were deemed to have responded well to therapy. Two patients with very high T2 values after chemotherapy developed wide-spread metastatic disease and died. Phosphorus-31 MR spectroscopy of five patients with osteosarcoma showed elevated levels of phosphomonoesters (PMEs), inorganic phosphate (Pi), and phosphodiesters (PDEs). PME and PDE peak areas decreased in three patients after chemotherapy, while Pi peak areas increased. 相似文献
43.
M. E. Kon’shin B. Ya. Syropyatov A. L. Efremov T. F. Odegova M. M. Vakhrin 《Pharmaceutical Chemistry Journal》2008,42(7):387-388
Chlorides of 2-arylaminocinchoninic acid pyridinioacetylhydrazides were synthesized via interaction of the chloroacetylhydrazides
of these acids with pyridine and its derivatives. These compounds showed antimicrobial activity and influenced blood coagulation.
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 42, No. 7, pp. 12–13, July, 2008. 相似文献
44.
45.
R Oner S Agarwal A J Dimovski G D Efremov G H Petkov C Altay A Gurgey T H Huisman 《Hemoglobin》1991,15(1-2):67-76
We describe the occurrence of a chromosome with a G----A mutation at position +22 relative to the Cap site that was found in five patients with beta-thalassemia. All patients had a common type of beta-thalassemia mutation on the second chromosome, namely the frameshift at codon 8 (-AA), the IVS-I-110 (G----A) and the IVS-II-1 (G----A) mutations. The beta genes of two patients, including the 5' and 3' untranslated regions, were completely sequenced and no other mutations, except a few polymorphic sites, were observed. Dot-blot analyses failed to demonstrate this G----A mutation at +22 in nearly 400 beta-thalassemia chromosomes and 180 normal chromosomes. Heterozygotes have the features of a high Hb A2-beta-thalassemia heterozygosity, although the hematological parameters might be less abnormal than observed in heterozygotes for the more common beta-thalassemia mutations. The possibility has been presented suggesting that this mutation might impair the binding of mRNA to ribosomes. Another mutation in this segment of DNA, i.e. a C----G mutation at position +20, is observed exclusively on a chromosome which also carries the C----G mutation at IVS-II-745. It is postulated that the +20 C----G mutation accentuates the beta-thalassemia condition caused by the IVS-II-745 mutation; the mechanism might be similar to that suggested for the G----A at +22 mutation. 相似文献
46.
While avid accumulation of gallium-67 citrate and technetium-99m methylene diphosphonate (MDP) occurs initially in most cases of primary Ewing sarcoma, uptake after therapy is less well defined. Thirty patients with Ewing sarcoma who underwent Ga-67 and bone scintigraphy at diagnosis, at completion of therapy, and at relapse from 1978 to 1988 were evaluated. All 30 patients showed less primary site Ga-67 activity following therapy. Twenty-three of 28 patients who underwent corresponding bone scintigraphy showed less uptake, but residual activity was usually more intense than with Ga-67. Avid reaccumulation of Ga-67 occurred in four of five patients with primary site relapse, while patients who underwent bone scintigraphy showed less change. It was concluded that a greater decrease in Ga-67 than in Tc-99m MDP uptake often occurs in patients successfully treated for primary Ewing sarcoma. Information obtained at Ga-67 scintigraphy is most likely to be helpful if results of bone scintigraphy remain abnormal or if occult relapse is suspected. 相似文献
47.
A A Baranauska?te E L Nasonov E E Efremov L V Kurmanova M V Eremeeva S K Solov'ev V Iu Kovalev O V Lopaeva A G Kobylianski? 《Terapevticheski? arkhiv》1991,63(5):75-78
EIA was used to measure the concentration of fibronectin in plasma and cryoprecipitates of 37 patients suffering from systemic lupus erythematosus coupled with cryoglobulinemia. A definite relationship was discovered between the level of cryoglobulins and the activity of SLE, the concentration of fibronectin in plasma and liver damage. A tendency was revealed towards increase of the fibronectin content in plasma of patients with a high level of antibodies to native DNA and CIC as was a significant correlation between the concentration of cryoglobulin protein and the concentration of fibronectin in cryoprecipitates. 相似文献
48.
Patricia Ann Firby MSc DipEd RGN RCNT RNT DipNurs Lecturer Karen A Luker PhD BNurs RGN RHV DN Cert Professor of Community Nursing Ann-Louise Caress BNurs RGN RHV DN Cert Research Assistant 《Journal of advanced nursing》1991,16(8):987-995
Computers have only recently begun to find a place in the everyday work of health care staff. The use of computer-assisted learning (CAL) in patient education is in its infancy. However, the medium appears to offer several advantages to patients. The successful integration of the medium into clinical practice requires the acceptance and support of staff members. Little research exists to date which examines staff responses to the introduction of CAL into their workplace. This small study (n = 14) aims to explore the reactions of staff to the introduction of an experimental CAL package for use in the education of renal patients on continuous ambulatory peritoneal dialysis (CAPD). The opinions of staff members to CAL are probed and their views ascertained regarding the usefulness of CAL to both staff and patients. Results suggest that, despite their initial reservations about CAL, staff were generally positive about the medium. 相似文献
49.
Image processing and volume rendering have been applied to magnetic resonance (MR) images to produce three-dimensional views of the surface of the brain. Four healthy volunteers and 17 patients with a variety of disorders underwent MR imaging of the head, and these images were processed and subjected to volume rendering. The resulting three-dimensional views depict abnormalities of the brain surface, as well as important landmarks of normal brain surface anatomy such as precentral, postcentral, superior temporal, and inferior frontal gyri, which are difficult to identify on cross-sectional images. 相似文献
50.