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71.
The effect of various treatments in vitro and in vivo on the binding of 125I-labeled anti-rat serum albumin Fab'' to rat tissue polyribosomes 总被引:1,自引:0,他引:1
With 125I-labeled Fab' specific for rat liver serine dehydratase it has been possible to localize polyribosomes synthesizing the enzyme under several different environmental conditions. Evidence is presented to show that, following the administration of amino acids in vivo, the relative synthetic capabilities of free and membrane-bound polyribosomes synthesizing serine dehydratase vary with time. Early during the period of induction of the enzyme by administration of amino acids or by feeding a high protein diet the majority of the newly synthesized enzyme is derived from membrane-bound polyribosomes. Later in the induction process an increasing proportion of the enzyme is synthesized by the free polyribosomes. Subcellular localization studies clearly show that serine dehydratase is synthesized by both subclasses of hepatic membrane-bound polyribosomes, the loose and tight membrane-bound polyribosomes, as well as by the free polyribosomes. It was found that the membrane-bound polyribosomes are the preferential sites of synthesis of the majority of serine dehydratase molecules in the Morris hepatomas 5123C and 7800. It is concluded that the synthesis of the enzyme, serine dehydratase, in rat liver is not discretely compartmentalized in either class of free or membrane-bound polyribosomes. Rather, the relative proportions of the serine dehydratase synthesizing polyribosomes within these two classes of polyribosomes can vary depending on the metabolic and physiologic state of the liver cell. 相似文献
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An infant with a typical Edwards syndrome and a modal chromosome number of 46 is reported. In all cells analyzed one chromosome G was missing and an additional chromosome similar to a pair No. 16 was present. The phenotype of the child indicates that the extra element is a translocation between G and 18 chromosomes as in one case described previously. 相似文献
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76.
Ethane-1-hydroxy-1, 1-diphosphonate (EHDP) was administered in a dose of 20 mg/kg/d to 21 patients with symptomatic Paget's disease. All patients were treated for 6 months and then followed for an additional 6 months. There was a striking decline in serum alkaline phosphatase and urinary hydroxy-proline excretion observed after 3 months of therapy which was not significantly improved in the succeeding 3 months. Concomitantly there was marked improvement in clinical symptoms and bone scans. Following cessation of therapy, continued biochemical and clinical evidence of remission persisted. Several patients on repeat treatment with EHDP appeared to respond promptly. Side effects were minimal except for a possibly related osteomalacia and increased incidence of pathologic fractures. 相似文献
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Gray scale B-scans in renal sinus lipomatosis show a variety of features which must be differentiated from clinically significant pathological processes. Normal kidneys show dense homogeneous central echoes. In renal sinus lipomatosis, however, the central echoes are divided and become more sparse (Type I), interspersed with small relatively echo-free areas (Type II), or outline a single relatively echo-free area resembling a mass (Type III). In contrast to similar features in hydronephrosis or multiple cysts, the relatively echo-free areas in lipomatosis are ill-defined and do present several weak internal echoes. 相似文献
79.
Chromosome analysis of lymphocytes from the peripheral blood of 20 patients with sarcoidosis and 10 healthy controls showed a significantly greater number of hypomodal cells among the patients. Two patients receiving systemic treatment with glucocorticoids had many chromosomal aberrations. 相似文献
80.
This study was based on 192 patients treated surgically for 228 metastatic lesions of the long bones from 1986 through 1995. The survival rate was 0.3 at 1 year after surgery. The surgical treatment consisted of resection and reconstruction of the involved bone (18), intralesional curettage (133), or stabilization only (77). Reconstruction was achieved by an endoprosthesis in 54 cases, by an osteosynthetic device in 162, by cement only in 10. In two cases no reconstruction was performed. The local failure rate was 11% and the median time to failure was 8 months. Local failure was most frequent in patients with kidney cancer (24%) and in diaphyseal and distal femoral lesions (20%). Among 162 operations involving osteosynthetic devices, 22 (14%) were failures as compared with one of 54 (2%) endoprostheses. Sixty percent of the patients received preoperative or postoperative radiotherapy. Five of the six patients who had surgery for local tumor progression had not received radiotherapy. Eight of 10 nonunions and all five patients who developed a stress fracture had been treated with radiotherapy. It is concluded that endoprosthetic reconstructions are preferable to osteosynthetic devices. The skeletal complications associated with radiotherapy may be circumvented by the use of endoprostheses. 相似文献