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981.
The bending response of sandwich plates with stiff laminated face sheets is studied by a six-noded triangular element having seven degrees of freedom at each node. The element formulation is based on a refined higher-order plate theory having all the features for an accurate modeling of sandwich plates with affordable unknowns. The refined plate theory is quite attractive but suffers from a problem concerned with an interelement continuity requirement when it is used in finite element analysis. The problem has been dealt satisfactorily in this new element, which is applied to the analysis of sandwich plates of different kinds. 相似文献
982.
E Mangieri G Tanzilli F Barillà M Ciavolella G Serafini M Nardi F Mangiaracina G Scibilia LJ Dell'Italia PP Campa 《Canadian Metallurgical Quarterly》1997,79(9):1261-1263
This study demonstrated an immediate and short-lasting endothelin-1 release in the circulation of patients with severe chronic congestive heart failure during isometric handgrip exercise, but not in normal subjects. Our data suggest that endothelin-1 levels may increase transiently during daily physical activity, thus contributing to progressive deterioration of left ventricular function. 相似文献
983.
984.
985.
N Sang PP Claudio Y Fu N Horikoshi U Graeven R Weinmann A Giordano 《Canadian Metallurgical Quarterly》1997,16(11):1321-1333
Conserved regions 1 and 2 as well as the amino terminus of E1A are required for the transforming activity of the E1A oncoprotein. We show here that the amino terminus of 243R E1A has transactivation activity when brought to a promoter in yeast. Recruitment to a specific promoter is essential. Mutagenesis studies correlated the transactivation function with the extreme amino terminus and the conserved region 1 of E1A. Cotransfection assays in rodent cells confirmed that two overlapping but distinguishable domains, amino acids 1-65 and 37-80, can transactivate independently when targeted to a promoter. We also observed that when recruited to the proliferating cell nuclear antigen (PCNA) promoter, the amino-terminal region was sufficient to transactivate the PCNA promoter. On the other hand, deletion of the amino terminus of E1A resulted in failure to induce PCNA expression. Fusion of VP16 with the amino-terminal-deleted E1A mutant was able to restore the ability to induce the PCNA promoter. We further show that the amino-terminal region also is required for 243R E1A to repress the transactivation mediated by a universal transactivator DBD.VP16 and DBD.E1A. This repression could be specifically relieved by overexpression of TBP but not TFIIB. In addition, we show that the amino terminus of E1A is involved in in vitro interaction with the TATA binding protein (TBP). Thus the amino-terminal transforming region of E1A may regulate cellular gene expression in species that are distant in evolution via a common mechanism, functionally targeting TBP. 相似文献
986.
G Fiore PP Donadio P Gianferrari C Santacroce A Guermani 《Canadian Metallurgical Quarterly》1998,64(3):83-87
OBJECTIVE: To evaluate CVVH (Continuous Veno-Venous Hemofiltration) as acute renal replacement treatment in postoperative care of liver transplantation. DESIGN: Retrospective study. SETTING: Intensive Care Unit, year 1995. PATIENTS: 86 OLT performed in 1995, 11 of them underwent acute renal replacement treatment. In the same period, in the ICU were admitted 237 patients, and 20 underwent acute renal replacement treatment (control group). Evaluation with SOFA (Sepsis-related Organ Failure Assessment) score. INTERVENTION: CVVH performed heparin free, pump system, polyamide or polysulphone 0.6 mq membrane hemofilter device, blood flow 150-200 ml/min, UF rate 1000-1200 ml/h, clearance 16-20 ml/min. MEASUREMENTS: Coagulation monitoring (PT as INR, PTT, fibrinogen, antithrombin III, d-dimer, platelet count) was performed 3 times a day or on variation of the clinical conditions. RESULTS: SOFA score did not differ between the two groups. Mortality was higher in the patients treated with CVVH. CVVH was performed from 16 to 18 hrs/day for 9.90 +/- 2.33 days. Three patients developed clinical bleeding before CVVH, 3 during CVVH but 1 of them underwent repeated surgical procedures. CONCLUSIONS: We cannot demonstrate that CVVH doesn't affect bleeding, but we can say that, for the complexity of the post OLT patients, CVVH can be the treatment of choice in case of renal replacement treatment. 相似文献
987.
988.
MC Rasch H Schellekens CM van Dijck EB Haagsma PP Michielsen AH van Buuren H St?tter J van Hattum 《Canadian Metallurgical Quarterly》1998,43(8):1719-1724
A novel recombinant interferon-alpha B/D hybrid was applied to assess tolerability, antiviral effect, and biological activity in chronic hepatitis B. The study was designed as an open nonrandomized trial. Treatment comprised a two-week run-in phase with 16 MU three times a week followed by 14 weeks with 64 MU three times a week (or 48 MU if toxicity occurred with 64 MU). Total follow-up was 36 weeks. Nineteen patients were included; three discontinued treatment during the run-in with 16 MU. Fourteen of 16 patients had 14 weeks of treatment with > or = 32 MU three times a week. Fourteen dose reductions were necessary in nine patients. The adverse experience profile was similar to other interferon-alphas. HBV-DNA decreased using all doses studied. HBV-DNA became undetectable in five patients, two of whom had HBeAg seroconversion. No HBsAg seroconversion was observed. It is concluded that interferon-alpha B/D is well tolerated in high doses. The anti-viral effect starts at at least 16 MU three times a week. 相似文献
989.
AJ Mundt PP Connell T Campbell JH Hwang J Rotmensch S Waggoner 《Canadian Metallurgical Quarterly》1998,71(2):151-158
Epidemiologic and in vitro data have shown that the association of house-dust mite (HDM) allergy and snail allergy in the same patients was due to cross-reactivity between HDM and snail allergenic components. However, the cross-reacting allergen(s) have not yet been identified. In vitro reactivity of seven patients' sera to the various extracts and hemolymph of four different Helix snail species was analyzed by IgE detection and immunodots and Western blots. Cross-reactivity between snails and Dermatophagoides pteronyssinus was assessed by immunodot and ELISA inhibition in two patients. Heterologous inhibition of the snail immunodot and ELISA was observed in one serum. Western blotting showed a specific binding on all four snail species extracts; molecular weights of snail allergens ranged from < 21 to 200 kDa. Marked individual differences were observed in the seven sera under study; most sera demonstrated IgE recognition of multiple bands, illustrating that no single allergen is responsible for cross-reactivity between snail and mite. These results confirm that cross-reactivity exists between snails of the Helix genus and HDM. This cross-reactivity, involving more than a single allergen, may be of clinical significance in atopic patients allergic to D. pteronyssinus. The identity of the cross-reacting allergens remains to be determined. Potential candidates include the thermostable minor allergens of D. pteronyssinus, tropomyosin and hemocyanin. 相似文献
990.
Drosophila imaginal discs undergo extensive pattern formation during larval development, resulting in each cell acquiring a specific adult fate. The final manifestation of this pattern into adult structures is dependent on pulses of the steroid hormone ecdysone during metamorphosis, which trigger disc eversion, elongation and differentiation. We have defined genetic criteria that allow us to screen for ecdysone-inducible regulatory genes that are required for this transformation from patterned disc to adult structure. We describe here the first genetic locus isolated using these criteria: crooked legs (crol). crol mutants die during pupal development with defects in adult head eversion and leg morphogenesis. The crol gene is induced by ecdysone during the onset of metamorphosis and encodes at least three protein isoforms that contain 12-18 C2H2 zinc fingers. Consistent with this sequence motif, crol mutations have stage-specific effects on ecdysone-regulated gene expression. The EcR ecdysone receptor, and the BR-C, E74 and E75 early regulatory genes, are submaximally induced in crol mutants in response to the prepupal ecdysone pulse. These changes in gene activity are consistent with the crol lethal phenotypes and provide a basis for understanding the molecular mechanisms of crol action. The genetic criteria described here provide a new direction for identifying regulators of adult tissue development during insect metamorphosis. 相似文献