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991.
992.
A longitudinal perspective was employed to test the hypothesis that there is an increased risk of hospitalization among Antarctic winter-over personnel during the first year subsequent to this duty. Subjects were 327 enlisted Navy men who wintered-over between 1963 and 1974 and a control group of 2,396 enlisted men who volunteered and were accepted for winter-over duty but who did not winter-over. A 15-year period from 1965 to 1979 was established for follow-up. Follow-up of subjects subsequent to screening for Operation Deep Freeze was conducted in 6-month intervals for the first 4 years. Results indicated that the total rates of first hospitalization during the 6 months prior to Antarctic duty and the first 6 months in Antarctica among winter-over personnel were significantly lower than the rates for the control group. No significant difference in the rates of the two groups was observed for the 12 months subsequent to winter-over duty.  相似文献   
993.
Human Daudi lymphoblastoid cells, which are highly sensitive to the antiproliferative action of human leukocyte alpha-interferon (IFN-alpha), and IFN-resistant and IFN-sensitive Daudi subclones (Cl2 and Cl1, respectively), contain 2300 (Kd = 20 X 10(-12) M), 3000 (Kd = 45 X 10(-12) M), and 3700 (Kd = 52 X 10(-12) M) IFN-alpha binding sites per cell, respectively. Thus, these IFN-sensitive and IFN-resistant cells have similar numbers of high-affinity IFN-alpha receptors. IFN-receptor complexes that are insoluble in Triton X-100 accumulate in IFN-sensitive but not in IFN-resistant cells. The ligand-induced accumulation of Triton-insoluble complexes in IFN-sensitive cells was inhibited by cytochalasin B. This suggests that the solubility change of IFN-receptor complexes results from their interaction with the cytoskeletal matrix. The dissociation of IFN-alpha from IFN-sensitive and IFN-resistant cells can be resolved into fast and slow components. IFN-alpha dissociates more slowly from IFN-sensitive cells than from IFN-resistant cells. Very slow dissociation of IFN-alpha from Triton-insoluble complexes correlates with this difference. These observations suggest that IFN-receptor complexes become coupled to the cytoskeletal matrix in IFN-sensitive but not in IFN-resistant cells, and that such interaction is an important element in the mechanism of the antiproliferative action of IFN-alpha on Daudi cells.  相似文献   
994.
Painful calcinosis appeared at the wrist of an eight-year-old girl with lead poisoning. Careful history revealed that calcification occurred at the site of previous extravasation of calcium disodium edetate (EDTA) used in chelation therapy. Light microscopic, ultrastructural, electron activation, and X-ray diffraction studies demonstrated apatites with some suggestion of an admixture of octacalcium phosphate.  相似文献   
995.
996.
Deep-frozen cancellous allografts have been used to restore the proximal femur of 23 hips following failed total hip arthroplasty. The canal is cleared and reaming is performed under direct vision through a cortical window. A modified Huckstep prosthesis permits early weight-bearing on the distal femur regardless of the state of proximal bone, but retains the option for later restoration of proximal loading once grafts appear mature. This transfer has been performed on four occasions. All 23 patients have had relief of pain with early ambulation. The follow-up periods ranged from six to 30 months. With the exception of one deep infection, the grafts have not undergone resorption in this period of follow-up study. Consolidation appears slower when the defect has followed multiple operations than following an initial revision for prosthetic loosening. The basic bone bank facilities are required for the supply of frozen allografts.  相似文献   
997.
998.
The mammalian stratum corneum, formerly treated as a homogeneous film, is now more properly viewed as a two-compartment system. The cornified cell is protein-enriched and lipid-depleted, lying embedded in an expanded extracellular matrix of highly nonpolar lipids. Because of its strategic location between the cornified layer, this lipid matrix is responsible for many phenomena related to the permeability barrier, as well as cohesion and desquamation. Thus, manipulation of this compartment could lead to enhanced drug delivery and improved lubrication, as well.  相似文献   
999.
Hypochlorite-promoted transformations of trichothecenes, 3. Deoxynivalenol   总被引:1,自引:0,他引:1  
Treatment of deoxynivalenol [3] in MeOH with hypochlorite bleach containing added NaOH gave rise to a single major product, the 9 alpha, 10 alpha, 12 beta, 13 beta-diepoxy-8,15-hemiketal 4. Thus, the reaction followed a very different course from that observed for verrucarol [2], where rearrangement involving opening of the starting 12,13-epoxide and a haloform-like oxidation took place.  相似文献   
1000.
Major depression with psychotic features, dementia, and focal neurologic abnormalities appeared in a Haitian man without AIDS or other syndromes of immune compromise. Neurologic evaluation, including brain biopsy, was nondiagnostic, but CSF culture revealed human immunodeficiency virus (HIV).  相似文献   
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