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Invasive monitoring is an important aspect of the care of the infant or child with multisystem organ dysfunction or severe acute respiratory failure. The indications for these procedures in children vary little from current recommendations for adults. The size, anatomy, physiologic responses, and pathophysiologic processes in children frequently require modifications in the placement and maintenance of these lines, and in the interpretation of the data. The literature suggests that although the absolute numbers may vary, broad therapeutic goals may be identified and treated in pediatric patients as in older patients.  相似文献   
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Angiotensin-converting enzyme (ACE) was studied immunohistochemically in conjunctival biopsies from 6 patients with systemic sarcoidosis, 4 patients with posterior non-sarcoid uveitis and in specimens from 4 patients with chalazion of the eyelid. Specimens with sarcoid granulomas showed intense ACE-positive immunoreactivity in epitheloid cells of the granuloma, whereas chalazion granulomas did not contain ACE-immunoreactivity. There was no difference in staining patterns between specimens without granulomas. Thus immunohistochemical staining for ACE may be of help in differentiating conjunctival granulomatous tissue of a chalazion from sarcoid granuloma.  相似文献   
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A consecutive series of patients (1978–1981) comprising all patients with acute leukaemia from a population of 475000 inhabitants was reviewed. Thus, 94 patients were diagnosed as having acute leukaemia. No patients were lost from follow-up. The incidence figures of ALL and AML differed significantly from those of Sweden as a whole. 9 patients were < 15 years old. The median age of adult patients was 64 years, 60.8% being ≥ 60 years old. Of adult patients with AML, 20% had a preleukaemic history (chronic myeloproliferative disorders, myelodysplastic syndromes and others). None of 6 patients with leukaemia as a metamorphosis of a chronic myeloproliferative disorder achieved a complete remission. The overall remission rate of the remaining adult patients was 25%. Treated patients, 15–39 years old, with AML without any preleukaemic history, had a complete remission rate of 80% compared to 12% for patients ≥ 60 years old with the same diagnosis. Of 60 patients with ‘primary’ AML, 14 were not treated, mainly because of advanced age and complicating diseases. Most of these patients died within a week of admission.  相似文献   
107.
Nerve growth factor (NGF) gene expression in central nervous system (CNS) glia appears to be associated with active glial growth. To study the underlying molecular mechanisms, we examined the effects of a number of growth-related factors on NGF mRNA expression in glial cultures. Our results suggest that glial membrane interaction, as a consequence of growth, actively inhibits NGF gene expression in CNS glia.  相似文献   
108.
Three isoforms of human tau protein were compared for their abilities to induce microtubule assembly. The three isoforms, tau 3 (tau containing three microtubule-binding domains), tau 4 (tau containing four microtubule-binding domains) and tau 4L (tau containing four microtubule binding domains plus a 58-amino-acid insert near the N-terminus) were expressed in E. coli and purified using ammonium sulfate precipitation, ion exchange, and size exclusion chromatography. All three isoforms induced microtubule assembly at micromolar concentrations and showed similar critical concentrations for assembly of 0.4-0.45 microM. However, tau 4 induced microtubule formation at a rate five- to tenfold faster than either tau 3 or tau 4L. The rate of microtubule elongation seen with tau 4 was twofold greater than with tau 3 or tau 4L, suggesting that the faster rate of microtubule assembly seen with tau 4 was due, at least in part, to faster elongation. Tau 4 induced a greater number of microtubules to form at steady state than did tau 3 or tau 4L. The microtubules generated with each tau isoform had similar steady-state length distributions and were equally susceptible to cold-induced disassembly. These results indicate that the additional microtubule-binding domain in tau 4 enhances microtubule assembly, while the 58-amino-acid insert negates the stimulatory effect of the fourth microtubule-binding domain.  相似文献   
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Thirty gallium scans, using currently acceptable dosage levels (5-6 mCi) and a conventional rotating gamma camera, were performed on 20 patients with lymphoma or infection. Compared to planar scans, SPECT increased sensitivity and lesion detection from 48% to 89% in lymphoma, and from 50% to 80% in infection. The predictive value of a negative site was 81% in lymphoma and 67% in infection. Gallium utility is markedly increased by SPECT imaging. A normal gallium SPECT scan is highly accurate in ruling out disease.  相似文献   
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