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11.
12.
Renal length has been measured by ultrasound in 237 subjects with homozygous sickle cell (SS) disease, 147 with sickle cell-hemoglobin C (SC) disease, and in 78 age-matched controls with a normal hemoglobin (AA) genotype. As expected, renal length increased with age in all genotypes but mean length was significantly greater in SS disease compared with SC disease (mean difference 4.3 mm after adjustment for height) and significantly greater in both genotypes than in AA controls (SS/AA difference 9.2 mm, SC/AA difference 5.0 mm after adjustment for height). Examination of relationships between renal length and some hematological indices (hemoglobin, fetal hemoglobin, reticulocyte counts, alpha thalassemia status) in SS or SC disease showed only a significant negative correlation with hemoglobin and positive correlation with reticulocyte count in SS disease. Further analysis suggested that the stronger relationship was between renal length and high reticulocyte count. The mechanism of renal enlargement is unknown although glomerular hypertrophy and increased renal blood volume are likely contributors. 相似文献
13.
M Hessing D Kanters H Takeya C van 't Veer TM Hackeng S Iwanaga BN Bouma 《Canadian Metallurgical Quarterly》1993,317(3):228-232
Human C4b-binding protein (C4BP) functions as a cofactor to factor I in the degradation of C4b and accelerates the decay rate of the C4b2a complex. In this study we describe a monoclonal antibody directed against the alpha-chain of C4BP that inhibits the binding of C4b to C4BP. In order to identify the structural domain of the alpha-chain of C4BP that interacts with C4b, tryptic fragments of C4BP were generated. Amino acid sequence analysis of the fragments revealed that the residues Ser333-Arg356 of the alpha-chain of C4BP contain the epitope of this antibody, and as a consequence, that this part of the alpha-chain of C4BP is likely to be involved in the interaction with C4b. 相似文献
14.
One hundred and six episodes of bleeding from esophageal or gastric varices in 72 patients with cirrhosis of the liver were randomized to treatment either with intravenous terlipressin 2 mg initially and 1 mg every four hours for 24 hours together with bolus injection and continuous infusion of placebo, or with somatostatin 250 micrograms as a bolus and continuous infusion of 250 micrograms/h somatostatin for 24 hours and placebo injections. Standard treatment with transfusions, fluid and electrolyte correction, and lactulose was administered in both groups. In the terlipressin group, 48 out of 53 bleeding episodes (91%) and in the somatostatin group 43 out of 53 bleeds (81%) were initially stopped by the vasoactive drugs. Four of the five bleeds not arrested by terlipressin, and nine of the ten bleeds not arrested by somatostatin, were stopped by balloon tamponade. In one patient in each group variceal bleeding could not be stopped initially, and both patients died. The failure rate of the vasoactive treatment alone, including rebleeds within the study period, was 17% in the terlipressin, and 28% in the somatostatin, group. The initial hemostasis, including balloon tamponade, were 98%, and the definitive bleeding control rates were 89% in both groups. The hospital mortality rate was 21% (11/53) in the terlipressin, and 21% (11/53) in the somatostatin, group. Blood transfusions and duration of bleeding did not differ significantly. The study indicates that a large proportion of bleeds from esophageal and fundic varices can be stopped initially (86%) and definitively controlled (77%) by vasoactive drugs alone. 相似文献
15.
CM Wheeler CA Parmenter WC Hunt TM Becker CE Greer A Hildesheim MM Manos 《Canadian Metallurgical Quarterly》1993,20(5):286-289
OBJECTIVES: To confirm the risk factors for genital human papillomavirus (HPV) infection. GOAL OF THIS STUDY: To investigate risk factors for HPV detection apart from the correlated risk factors for cervical neoplasia. STUDY DESIGN: Cervical human papillomavirus (HPV) DNA was assessed in 357 cytologically normal women attending the University of New Mexico student health center. Cervical swab samples were obtained for HPV DNA detection and typing using a PCR-based DNA amplification system. Possible determinants of cervical HPV were examined including age, ethnicity, history of sexually transmitted disease, oral contraceptive use, smoking, age at first intercourse, lifetime number of sex partners, marital status, and history of pregnancy. RESULTS: A 44.3% overall prevalence of cervical HPV was observed. On univariate analysis, factors associated with increasing HPV prevalence included higher lifetime number of sex partners and single marital status. After adjustment for potential confounding variables, we found that HPV prevalence increased with higher lifetime number of sexual partners. CONCLUSION: These findings, along with those from the companion reports in this issue of the journal, support the sexual route of transmission of the virus. 相似文献
16.
F. Wastin J. Rebizant J.P. Sanchez A. Blaise J. Goffart J.C. Spirlet C.T. Walker J. Fuger 《Journal of Alloys and Compounds》1994,210(1-2):83-89
Twelve new ternary intermetallic compounds of light actinide elements from Th to Pu, namely U4Tc7Si6, U4Tc7Ge6, Np4Ru7Ge6, U2Tc3Si5, Np2Re3Si5, Pu2Re3Si5, Th2Mo3Si4, U2Mo3Si4, U2Mo3Ge4, Np2Mo3Si4, Np2Mo3Ge4, and Pu2Mo3Si4, were obtained. The structures of these compounds are discussed as well as some preliminary physical property studies. Magnetic susceptibility measurements show that An2Mo3(Si or Ge)4 compounds are paramagnetic at all temperatures studied and that U4Tc7Si6 orders antiferromagnetically around 25 K. Mössbauer spectroscopy on Np4Ru7Ge6 does not show a magnetic splitting down to 4.2 K. 相似文献
17.
D.L Orphal C.E Anderson Jr. R.R Franzen J.D Walker P.N Schneidewind M.E Majerus 《International Journal of Impact Engineering》1993,14(1-4):551-560
Calculations of steel target penetration by L/D ≤ 1 tungsten and tungsten alloy projectiles have been extended to L/D = 1/32 over the velocity range 1.5 to 5 km/s. The ratio of crater to projectile diameter tends to 1 as L/D decreases over this entire velocity range. For impact velocities of 1.5 and 3 km/s, penetration depth normalized by projectile length, P/L, increases with decreasing projectile L/D up to a maximum value and then decreases for still lower L/D. Experiments at impact velocities of 2 and 3 km/s confirm these results. For 5 km/s impact velocity, the calculations show P/L increasing with decreasing projectile L/D over the entire range 1/32 ≤ L/D ≤ 1. The projectile L/D for which the maximum P/L occurs appears to depend on the impact velocity. P/L generally scales with impact velocity as P/L vf(L/D) where f(L/D) ranges from 0 for a long rod to, we believe, 2 in the limit as projectile L/D approaches zero. The calculations show for 1/8 ≤ L/D ≤ 1/2, P/L v0.9; for L/D = 1/16, P/L v1.5; and for L/D = 1/32, the new results give P/L v1.9. 相似文献
18.
The effects of chronic injection of U50,488H (trans-3,4-dichloro-N-[2-(1-pyrrolidinyl)cyclohexyl]benzeacetamidel++ +), a selective kappa opioid agonist, on the properties of the binding sites of tritiated U69593 [(5 alpha,7 alpha,8 beta)-(-)-N-methyl-N-(7-(1-pyrrolidinyl)-1-oxaspiro (4,5)dec-8-yl)benzeneacetamide], another selective kappa opioid agonist, and mechanical responses to U50,488H of the heart were studied. Rats received injection twice a day with U50,488H for 4 days. Binding studies on the crude membrane homogenates revealed that there was no change in maximum binding, but a significant increase in Kd after the treatment, indicating that the number of kappa binding sites remained unchanged whereas the affinity of the binding sites to kappa-agonist decreased. The study on the mechanical responses to U50,488H in the isolated perfused heart preparation showed that although the agonist at 10(-6) M caused MR2266 reversible reductions in heart rate and force of contraction as well as ventricular ectopic beat in the heart of rats in the control group, its effects were absent in the U50,488H-treated group, indicating the development of tolerance to the mechanical effects of U50,488H on the heart. The results indicate that the development of tolerance to the mechanical effects of a kappa-agonist after chronic treatment with the agonist was not accompanied by down-regulation, but only a slight and significant reduction in affinity of kappa binding sites in the rat heart. 相似文献
19.
Jing Wang Walker D.M. Xiang Lu Majhi A. Kruseman B. Gronthoud G. Villagra L.E. van de Wiel P.J.A. Eichenberger S. 《Design & Test of Computers, IEEE》2007,24(3):226-234
Excessive power supply noise during test can cause overkill. This article discusses two models for supply noise in delay testing and their application to test compaction. The proposed noise models avoid complicated power network analysis, making them much faster than existing power noise analysis tools. can cause performance degradation and 相似文献
20.
An adaptive alignment scheme for packaging two-dimensional (2D) arrays of optoelectronic systems interconnected by free-space optics is presented. A method of using three quadrant detectors to detect alignment errors in six degrees of freedom is described. However, the complexity of this system increases due to the interactions among the detected error signals. A novel control algorithm is presented to eliminate the interaction and simplify the design of the closed-loop feedback control. A computer simulation compares different algorithms and shows the effectiveness of the proposed algorithm. An experimental closed-loop feedback system demonstrated the principle of the error detection and correction of the proposed system with initial errors in multiple degrees of freedom 相似文献