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951.
DT Simeon SM Grantham-McGregor SP Walker CA Powell 《Canadian Metallurgical Quarterly》1993,87(5):526-528
This is the first report of the effects of a hurricane on children's health and nutritional status in which data were available preceding and following the event. When Hurricane Gilbert struck Jamaica in 1988, a longitudinal study was in progress in which children's weights and heights were recorded every 2 months and their morbidity histories taken every week. The investigation included 127 stunted (low height-for-age) and 32 non-stunted children aged 23-44 months, living in poor areas of Kingston. The data from the 4 months before and after the hurricane were compared. There was an increase in the occurrence of respiratory symptoms including rapid or difficult breathing (P < 0.04), coughs (P < 0.001) and nasal discharges (P < 0.001) during the first 2-month period after the hurricane. However there was no significant effect on the occurrence of diarrhoea and injuries. Deficits were also found in height gain (P < 0.001) during the same period. These adverse effects were found in spite of the large amount of food aid received and the aggressive health education programme implemented after the hurricane. 相似文献
952.
Purification and characterization of endogenous digoxin-like immunoreactive factors in chicken blood
JS Wei HC Cheng KJ Tsai DH Liu HH Lee DT Chiu TZ Liu 《Canadian Metallurgical Quarterly》1996,59(19):1617-1629
Studies have been performed to determine whether an endogenous material capable of binding to digoxin antibodies is present in the chicken plasma. In the blood of 12 chickens without feed control, endogenous digoxin-like immunoreactive factors (DLIF) binding of digoxin antibodies in enzyme immunoassays amounted to 866 / 302 pg digoxin equivalents/mL of plasma (mean +/- SEM). Immunoreactivity of DLIF increased to 1848***331 pg/mL with a double value of control after boiling and acid pretreating the plasma. The major purification steps employed in this report were gel filtration column chromatography, high performance liquid chromatography (HPLC) and isoelectric focusing (IEF). Using HPLC for the separation, at least 10 chicken DLIFs with different molecular weight (MW) have been found. The MW of the smallest is 300 daltons (Da) while the largest is 100 kDa. The value of the isoelectric point of the most abundant type of DLIF from untreated chicken plasma is 6.3 as determined by IEF. The partially purified DLIF inhibits Na+, K(+)-ATPase from a porcine cerebral cortex as well as three human red blood cell membrane preparations in a dose-response fashion. 相似文献
953.
OBJECTIVE: To test the hypothesis that interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) regulate granulocyte colony-stimulating factor (G-CSF) production by human placental villous core mesenchymal cells. METHODS: Villous core mesenchymal cells were isolated from placentas at 14-20 weeks' gestation and cultured in vitro. Cells were treated with IL-1 beta or TNF-alpha in dose-response and time-course studies. We measured G-CSF mRNA expression by Northern blot analysis and G-CSF protein production by enzyme-linked immunosorbent assay of the conditioned media. RESULTS: Unstimulated mesenchymal cells expressed negligible G-CSF. Steady-state G-CSF mRNA expression was maximal 3-6 hours after IL-1 beta treatment and 6-18 hours after TNF-alpha treatment. Each cytokine induced G-CSF protein production in dose-and time-dependent manners, with IL-1 beta more potent than TNF-alpha. The G-CSF mRNA expression and G-CSF protein production induced by the combination of both cytokines exceeded that induced by either cytokine alone. CONCLUSIONS: Interleukin-1 beta and TNF-alpha stimulate G-CSF production by placental villous core mesenchymal cells in vitro. These results identify a potential mechanism by which villous core mesenchymal cells mediate, in part, the placental response to these two cytokines. 相似文献
954.
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956.
PA Marcovitz V Shayna RA Horn A Hepner WF Armstrong 《Canadian Metallurgical Quarterly》1996,78(4):404-408
Although the accuracy of dobutamine stress echo (DSE) for detecting coronary artery disease (CAD) has been established, its role in determining prognosis is less well defined. The purpose of this study was to evaluate the prognostic significance of DSE in patients with known or suspected CAD. Follow-up was obtained on 291 patients an average of 15 months after clinically indicated DSE. Studies were stratified with respect to resting and inducible wall motion abnormalities into 1 of 4 responses: normal, ischemic, fixed, and mixed. Hard end points of nonfatal myocardial infarction and cardiac death were tabulated for outcome. Statistically significant differences in the incidence of hard cardiac end points were noted for 2 of 4 DSE responses. A normal DSE was associated with a statistically lower likelihood of a hard cardiac event than was a DSE demonstrating resting or inducible abnormalities (p = 0.001). DSE with a mixed response (resting abnormality with additional inducible ischemia) was associated with a higher likelihood of cardiac events by multivariate analysis (p = 0.003). By multiple logistic regression analysis of dobutamine response, age, and cardiac risk factors, only a mixed response on DSE was independently associated with the occurrence of a hard cardiac event in the follow-up period. In addition, left ventricular dysfunction on the resting echocardiogram was associated with a worse prognosis in patients with major noncardiac disease. We conclude that dobutamine response is an independent predictor of cardiac events compared with traditional risk factor analysis and that DSE can identify high- and low-risk subsets of patients with known or suspected CAD. 相似文献
957.
JT Douglas BE Rogers ME Rosenfeld SI Michael M Feng DT Curiel 《Canadian Metallurgical Quarterly》1996,14(11):1574-1578
The utility of adenoviral vectors for gene therapy is currently limited due, in part, to the widespread distribution of the cellular receptor for the adenovirus fiber that precludes the targeting of specific cell types. In order to develop a targeted adenovirus, it is therefore necessary both to ablate endogenous viral tropism and to introduce novel tropism. We hypothesized that these two goals could be achieved by employing a neutralizing anti-fiber antibody, or antibody fragment, chemically conjugated to a cell-specific ligand. To test this concept, we chose to target the folate receptor, which is overexpressed on the surface of a variety of malignant cells. Therefore, we conjugated folate to the neutralizing Fab fragment of an anti-fiber monoclonal antibody. This Fab-folate conjugate was complexed with an adenoviral vector carrying the luciferase reporter gene and was shown to redirect adenoviral infection of target cells via the folate receptor at a high efficiency. Furthermore, when complexed with an adenoviral vector carrying the gene for herpes simplex virus thymidine kinase, the Fab-folate conjugate mediated the specific killing of cells that overexpress the folate receptor. This work thus represents the first demonstration of the retargeting of a recombinant adenoviral vector via a non-adenoviral cellular receptor. 相似文献
958.
The thermal stresses that may develop due to crystal anisotropy within the microstructure of beryllium and certain other hcp
materials are described. The magnitude of the unrelaxed thermal stress in polycrystalline beryllium is estimated numerically.
The calculated values for the local thermal stresses that might occur in polycrystalline beryllium are comparable to the bulk
stresses that are measured for yielding and fracture. The possible influence of these stresses on the initiation of cleavage
cracks in rolled beryllium sheet and in extruded beryllium plate is described.
N. R. Borch, formerly with Lawrence Radiatior. Laboratory, University of California, Livermore, Calif. 相似文献
959.
D4 dopamine receptor-mediated signaling events determined in transfected Chinese hamster ovary cells
CL Chio RF Drong DT Riley GS Gill JL Slightom RM Huff 《Canadian Metallurgical Quarterly》1994,269(16):11813-11819
A Chinese hamster ovary (CHO) cell line stably expressing a recombinant human D4 dopamine receptor made from a synthetic gene has been used to determine potential D4-mediated signaling events. We designed and synthesized a modified gene coding for a human D4 receptor with reduced G + C content but unaltered encoded amino acids. Stable expression of this gene was obtained in two cell lines, inducible expression in CHO lacI cells and constitutive expression in HEK293 cells. In CHO lacI cells induced to express D4 receptors but not in uninduced cells, dopamine and quinpirole inhibit forskolin-stimulated cAMP accumulation and potentiate ATP-stimulated [3H]arachidonic acid release through a mechanism that requires protein kinase C but is unaffected by membrane-soluble cAMP analogs. In addition, D4 receptor activation causes an increase in the rate of extracellular acidification measured by microphysiometry. This response is unaffected by protein kinase C down-regulation but is inhibited by removal of extracellular sodium and inhibitors of NaH-1 exchange, suggesting the involvement of a Na+/H+ exchanger. All responses are blocked by clozapine and are sensitive to pertussis toxin. D4 receptors, like other G(i)/G(o)-linked receptors, mediate multiple signaling events, and the pathways activated are similar to those used by D2 and D3 receptors expressed in similar cells. 相似文献
960.