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31.
Twenty-one children who had been diagnosed as having laryngomalacia by direct laryngoscopy in infancy were reviewed 7 to 12 years later. The natural history of the disease is documented. A wide variation in the time of onset and duration of the stridor was found and there was a high incidence of feeding difficulties. A previously reported association with mental retardation or cerebral palsy is not confirmed. 4 out of the 21 children had early speech problems. 相似文献
32.
In an infant with Menkes's steely-hair syndrome, early treatment (from 21 days of age) with parenteral copper failed to halt the disease. In addition to urinary tract abnormalities, panlobular emphysema was present a finding not previously noted in the syndrome. 相似文献
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Platelets secrete a low-molecular-weight protein, platelet factor four (PF-4), which binds to and neutralizes heparin and related sulfated glycosaminoglycans (GAGs). To examine the interactions of PF-4 with the GAGs present on endothelial cell surfaces, we incubated 125I-PF-4 with cell suspensions derived from confluent monolayers of cultured bovine aortic endothelium. Binding of 125I-PF-4 was inhibited by a 100-fold excess of nonradioactive PF-4 and varied with duration and temperature of incubation. At 4 degrees C, binding reached equilibrium at 20 minutes with kd = 2.87 mumol/L and Bmax of 63.83 pmol/10(5) cells. Binding capacity was reduced 83.4% by brief incubation of endothelial cells with trypsin and 46.67% by incubation with Flavobacterium heparinase, but was unchanged by chondroitin-ABCase treatment. At 37 degrees C, PF-4 was internalized by confluent monolayer of bovine aortic endothelial cells primarily through low-affinity adsorptive endocytosis. The internalized PF-4 was degraded to amino acids and small peptides with 50% conversion after 18-hour incubation. These studies demonstrate that a secreted platelet protein can bind to and enter endothelial cells. Binding may explain the rapid clearance of released PF-4 from plasma and could have important local effects on endothelial structure and function. 相似文献
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Mueller PR; Silverman SG; Tung G; Brink JA; Cardenosa G; Saini S; Forman BH; Hahn PF 《Radiology》1989,173(1):278-279
A new tray has been designed for use during procedures involving needles and other sharp objects. The tray includes a foam adhesive pad, marked into 10 sections, into which the sharp objects can be placed point first. After the procedure, the objects can be safely withdrawn by their handles and then discarded. The tray has been used in more than 250 procedures. 相似文献
37.
Superparamagnetic iron oxide-enhanced MR imaging: pulse sequence optimization for detection of liver cancer 总被引:3,自引:0,他引:3
Fretz CJ; Elizondo G; Weissleder R; Hahn PF; Stark DD; Ferrucci JT Jr 《Radiology》1989,172(2):393-397
The effects of magnetic resonance (MR) pulse sequences and timing parameters on tumor-liver contrast were studied in an animal model of metastatic liver cancer. Six spin-echo (SE), three inversion-recovery (IR), and four gradient-echo (GRE) sequences were evaluated at 0.6 T before and after injection of super-paramagnetic iron oxide. GRE techniques, irrespective of echo time and flip angle, showed the greatest change in signal intensity (enhancement) of the liver after administration of iron oxide. Single-acquisition GRE sequences (16 seconds) matched the contrast-to-noise ratio (C/N) performance of the most effective 6.4-minute SE sequences. Multiexcitation GRE sequences showed tumor-liver C/Ns per unit time that were significantly (P less than .05) higher than those achieved with SE and IR sequences. GRE sequences, which recruit intravoxel dephasing as an additional source of transverse relaxation enhancement (T2*), show a higher C/N per unit time and in this respect seem superior to SE and IR sequences for MR imaging with superparamagnetic iron oxide. 相似文献
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Krabbe KS Mortensen EL Avlund K Pilegaard H Christiansen L Pedersen AN Schroll M Jørgensen T Pedersen BK Bruunsgaard H 《Neurobiology of aging》2009,30(5):769-781
The purpose of the study was to test the hypothesis that single nucleotide polymorphisms (SNPs) within interleukin (IL)-18, TNF-alpha, IL-6 and IL-10 gene promoter regions are risk factors for cognitive decline in healthy octogenarians, and to isolate the strongest inflammatory biomarkers of cognitive function in the peripheral blood. The Wechsler Adult Intelligence Scale was administered to 112 individuals at ages 80 and 85. An IL-18 haplotype was an independent risk factor of poor Performance IQ. The TNF-308GA genotype was related to individual declines in Verbal IQ, and the IL-10-592 CC genotype was related to better Verbal IQ at the age of 80. Circulating levels of TNF-alpha, sTNFRs, and IL-6 were negatively correlated with IQ at age 85 and less strongly to IQ at age 80 with activation of the TNF system as the strongest biomarker. In conclusion, SNPs related to high proinflammatory or low anti-inflammatory activity are independent risk factors of reduced cognitive function in octogenarians. Only the IL-18 haplotype was associated with inflammation in the peripheral blood and only with regard to circulating TNF-alpha. 相似文献
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