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61.
Changes in insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding proteins (IGFBPs) were correlated with protein synthesis and breakdown using [1- 13C]leucine before chemotherapy and during subsequent febrile neutropenia (FN) in eight children with cancer, aged 6.3–17.5 y. IGF-I levels were similar to age-matched controls before chemotherapy (mean ±SEM: 250 ±28 and 228 ±22 μg l-1, respectively). During FN, IGF-I fell to 156 ±22 /ng l -1(p= 0:02), and rose to 276 ±27 μ g l -1 with recovery at 6 months (p = 0:004). Similarly, IGFBP-3 decreased from 4.0 ±0.2mgl-1 before chemotherapy to 3.0 ±0.3 mgl-1 during FN (p= 0:01), and returned to 4.1 ±0.2mgl -1 at 6 months (p= 0:01). IGF-I correlated with IGFBP-3 (r=+0:7, p <0:001). Scanning densitometry showed a decrease in IGFBP-3 from 94 to 54% during FN, when the presence of IGFBP-3 protease activity was observed. Compared with normal human serum, IGFBP-2 was elevated throughout the study. IGFBP-1 increased from 14.6 ±3.5 to 30.6 ±2.8/ngl-1 (p = 0:004), whereas serum insulin decreased from 26.5 ±6.8 to 7.8 ±0.8 mUl-1 (p= 0:03) before and during FN, respectively. Whilst IGF-I and IGFBP-3 fell, daytime growth hormone increased from 3.3 ±0.6 to 6.7±0.8mUl -1 (p= 0:01), and cortisol from 197 ±48 to 594±98nmoll -1 (p = 0:005). Albumin decreased from 47 ±2 to 38 ±2gl-1 (p= 0:004) and improved to 47 ±2gl-1 with recovery (p= 0:003). Protein synthesis increased from 4.5 ±0.4 to 5.0 ±0.6gkg-1 d-1 before chemotherapy and during FN, while protein breakdown rose from 5.4 ±0.4 to 6.3 ±0.4kg-1d-1. Increasing protein breakdown was related to falling IGF-I and IGFBP-3 levels. Modification of IGFBP-3 by circulating proteolytic activity may alter IGF bioavailability, allowing protein synthesis to increase during periods of severe catabolic stress.  相似文献   
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Pretibial myxoedema is a cutaneous mucinosis typically associated with Graves' disease, although it may also develop in subjects with non-thyrotoxic thyroid pathologies. This report presents a rare case of pretibial myxoedema occurring in a 58-year-old woman with biopsy-proven Hashimoto's thyroiditis. The hypothetical pathogenetic link between the two disorders is discussed with particular attention to the role of thyroid stimulating hormone receptor antibodies.  相似文献   
64.
Sendai virus multiplication in the presence of ceruloplasmin resulted in the appearance of qualitatively modified progens. There was an increase in the proportion of incomplete virus particles and a decrease in hemagglutinin and neuraminidase activities, in virus infectivity and antigenicity (with the exception of subviral fractions with predominant hemagglutinating activity). Virus progens obtained in the presence of ceruloplasmin had a higher sensitivity to detergent treatment; virus ghosts formed by re-aggregation of envelope fragments could be observed in the electron microscope.  相似文献   
65.
Sanders  NL; Bajaj  SP; Zivelin  A; Rapaport  SI 《Blood》1985,66(1):204-212
A study was carried out to explore requirements for the inhibition of tissue factor-factor VIIa enzymatic activity in plasma. Reaction mixtures contained plasma, 3H-factor IX or 3H-factor X, tissue factor (vol/vol 2.4% to 24%), and calcium. Tissue factor-factor VIIa activity was evaluated from progress curves of activation of factor IX or factor X, plotted from tritiated activation peptide release data. With normal plasma, progress curves exhibited initial limited activation followed by a plateau indicative of loss of tissue factor-factor VIIa activity. With hereditary factor X-deficient plasma treated with factor X antibodies, progress curves revealed full factor IX activation. Adding only 0.4 micrograms/mL factor X (final concentration) could restore inhibition. Inhibition was not observed in purified systems containing 6% to 24% tissue factor, factor VII, 0.5 micrograms/mL, factor IX, 13 micrograms/mL, and factor X up to 0.8 micrograms/mL, but could be induced by adding barium-absorbed plasma to the reaction mixture. Thus, both factor X and an additional material in plasma were required for inhibition. The amount of factor X needed appeared related to the concentration of tissue factor; adding more tissue factor at the plateau of a progress curve induced further activation. These results also indicate that inhibited reaction mixtures contained active free factor VII(a). Preliminary data suggest that inhibition may stem from loss of activity of the tissue factor component of the tissue factor- factor VII(a) complex.  相似文献   
66.
A case of intracranial meningioma is reported in a 5-month-old infant. To date, 25 cases have been reported in the world literature in children less than 1 year of age. Macrocephaly was the most prominent clinical finding. Skull radiological studies, head CT scans, and cerebral angiography were definitive tools in making the diagnosis. Pathological analysis was conclusive. Complete surgical extirpation was the treatment of choice; the tumor weighed 600 g. The child remains stable 24 months later.  相似文献   
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Invasiveness and metastatic potential are the two most important properties defining malignancy. The adeno-virus E1A (Ad-E1A) gene has a dual effect as a proliferative gene and as a tumor-suppressor gene, decreasing tumor growth and the metastatic potential of malignant cells. In order to study genes related with the antimetastatic effect of Ad-E1A in human cells, we performed a microarray analysis using OncoChiptrade mark. In three independent experiments, NIH3T3, IMR90 and MDA MB 435 cells were infected with pLPC retroviruses carrying the adenovirus 12S E1A gene or the GFP gene. We analyzed cDNA expression by using the CNIO OncoChipTM, a cDNA microarray containing a total of 6386 genes represented by 7237 clones. uPA, uPAr, tPA, PAI-1 and PAI-2 were also studied at RNA and protein levels. Microarrays of cDNA expression, RT-PCR and Western blot performed in IMR90 E1A-expressing cells showed downregulation of uPA, uPAr, tPA, PAI-1 and upregulation of PAI-2. These results were confirmed in NIH3T3 and MDA MB 435 breast carcinoma cells, with PAI-2 upregulation by RT-PCR and Western blot. In addition, zymographic analysis demonstrated that E1A expression greatly reduced the gelatinase activity of the pro-MMP2 and -MMP9 proteins. We propose that adenovirus E1A may orchestrate the expression of most members of the urokinase-plasminogen activation system, downregulating potentially invasive genes and upregulating PAI-2, which is associated with a better prognosis in human tumors.  相似文献   
70.
Persistent primitive sciatic artery   总被引:1,自引:0,他引:1  
  相似文献   
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