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61.
62.
Epilog, a Unix-based real-time operational support system for electroencephalogram (EEG) waveform acquisition, storage, analysis, display, and printing, is described. The system is designed to be used for diagnosis and surgical planning in a large epilepsy program. The implemented system has two monitoring units consisting of four rooms with their associated computer, video, and medical support systems. A central computer hub performs Epilog services for each unit. Each hub acquires and processes up to 256 channels of EEG 24 h per day, and serves as a control center for much of the automation in the unit. The EEG data structures and data flow used in Epilog are discussed.<> 相似文献
63.
Ribonuclease A variants with potent cytotoxic activity 总被引:1,自引:0,他引:1
Select members of the bovine pancreatic ribonuclease A (RNase A) superfamily are potent cytotoxins. These cytotoxic ribonucleases enter the cytosol, where they degrade cellular RNA and cause cell death. Ribonuclease inhibitor (RI), a cytosolic protein, binds to members of the RNase A superfamily with inhibition constants that span 10 orders of magnitude. Here, we show that the affinity of a ribonuclease for RI plays an integral role in defining the potency of a cytotoxic ribonuclease. RNase A is not cytotoxic and binds RI with high affinity. Onconase, a cytotoxic RNase A homolog, binds RI with low affinity. To disrupt the RI-RNase A interaction, three RNase A residues (Asp-38, Gly-88, and Ala-109) that form multiple contacts with RI were replaced with arginine. Replacing Asp-38 and Ala-109 with an arginine residue has no effect on the RI-RNase interaction. In addition, these variants are not cytotoxic. In contrast, replacing Gly-88 with an arginine residue yields a ribonuclease (G88R RNase A) that retains catalytic activity in the presence of RI and is cytotoxic to a transformed cell line. Replacing Gly-88 with aspartate also yields a ribonuclease (G88D RNase A) with a decreased affinity for RI and cytotoxic activity. The cytotoxic potency of onconase, G88R RNase A, and G88D RNase A correlate with RI evasion. We conclude that ribonucleases that retain catalytic activity in the presence of RI are cytotoxins. This finding portends the development of a class of chemotherapeutic agents based on pancreatic ribonucleases. 相似文献
64.
Dietary conjugated linoleic acid normalizes impaired glucose tolerance in the Zucker diabetic fatty fa/fa rat 总被引:2,自引:0,他引:2
KL Houseknecht JP Vanden Heuvel SY Moya-Camarena CP Portocarrero LW Peck KP Nickel MA Belury 《Canadian Metallurgical Quarterly》1998,244(3):678-682
Conjugated linoleic acid (CLA) is a naturally occurring fatty acid which has anti-carcinogenic and anti-atherogenic properties. CLA activates PPAR alpha in liver, and shares functional similarities to ligands of PPAR gamma, the thiazolidinediones, which are potent insulin sensitizers. We provide the first evidence that CLA is able to normalize impaired glucose tolerance and improve hyperinsulinemia in the pre-diabetic ZDF rat. Additionally, dietary CLA increased steady state levels of aP2 mRNA in adipose tissue of fatty ZDF rats compared to controls, consistent with activation of PPAR gamma. The insulin sensitizing effects of CLA are due, at least in part, to activation of PPAR gamma since increasing levels of CLA induced a dose-dependent transactivation of PPAR gamma in CV-1 cells cotransfected with PPAR gamma and PPRE X 3-luciferase reporter construct. CLA effects on glucose tolerance and glucose homeostasis indicate that dietary CLA may prove to be an important therapy for the prevention and treatment of NIDDM. 相似文献
65.
Plain film imaging remains important for the diagnosis and surveillance of scoliosis, as well as for the detection of complications after surgery. New means of treating scoliosis have become established and should be understood by the radiologist. To the well-known postoperative complications, including pneumothorax, pneumonia, and gastrointestinal obstruction, are added new specific potential problems with the new surgical methodology. 相似文献
66.
67.
PA Fowler LW Evans NP Groome A Templeton PG Knight 《Canadian Metallurgical Quarterly》1998,13(12):3530-3536
Maternal serum concentrations of inhibin-A, inhibin-B, activin-A, activin-AB, pro-alphaC-related inhibin forms, total follistatin, steroids and gonadotrophins were measured longitudinally in six normal singleton pregnancies. Maternal venous blood was collected randomly during a spontaneous follicular phase prior to donor insemination, at 5, 7, 9, 11, 16, 20, 24, 28, 32 and 36 weeks after the first missed menses and in the early puerperium. Steroid and gonadotrophin profiles conformed to previous reports. While at week 5 of gestation inhibin-A, activin-A and follistatin concentrations were similar to those at the follicular phase, all three increased progressively (P < 0.001) to maximal concentrations in week 36: approximately 48-fold (3740 +/- 1349 ng inhibin-A/ml), approximately 22-fold (6109 +/- 1443 ng activin-A/ml) and approximately 10-fold (3563 +/- 418 ng follistatin/ml) higher. Pro-alphaC concentrations reached a maximum in weeks 5 (approximately 5-fold, P < 0.001) and 36 (1027 +/- 174 pg/ml, P < 0.01). Inhibin-B (71 +/- 23 pg/ml prior to pregnancy) was undetectable (<12 pg/ml) between week 5-16 of gestation but increased slightly in the third trimester (26 +/- 7 pg/ml in week 36). Activin-AB was undetectable throughout pregnancy. Post-partum concentrations of inhibin-A (41 +/- 12 ng/ml), inhibin-B (<12 pg/ml), activin-A (950 +/- 149 pg/ml), pro-alphaC (128 +/- 22 pg/ml) and follistatin (990 +/- 79 ng/ml) were substantially lower than at week 36 of gestation. The activin-A:follistatin ratio increased from 0.5 in week 5 to 1.8 in week 36, suggesting that more free activin-A is available in the maternal circulation during late pregnancy. 相似文献
68.
TP Le LW Church G Corradin RL Hunter Y Charoenvit R Wang P de la Vega J Sacci WR Ballou N Kolodny S Kitov GM Glenn RL Richards CR Alving SL Hoffman 《Canadian Metallurgical Quarterly》1998,16(2-3):305-312
Only low antibody levels were obtained from vaccinating human volunteers with single-chain peptide from the Plasmodium falciparum circumsporozoite protein (PfCSP). This resulted in modest protection against sporozoite challenge. In addition, HLA restriction limits the probability of synthesis of a vaccine effective for a diverse population. We report immunization studies with a multiple antigen peptide (MAP) system consisting of multiple copies of a B-cell epitope from the central repeat region of the PfCSP in combination with a universal T-cell epitope, the P2P30 portion of tetanus toxin. This MAP4(NANP)6P2P30 vaccine was highly immunogenic in four different strains of mice when used with various safe and nontoxic adjuvants. When this MAP vaccine was encapsulated in liposomes with lipid A and adsorbed to aluminium hydroxide and given three times at 4-week intervals, the resultant antibody prevented 100% of sporozoites from invading and developing into liver stage infection. This high degree of immunogenicity of MAP4(NANP)6P2P30 vaccine formulated in liposomes, lipid A and aluminum hydroxide provides the foundation for consideration of human trials with this formulation. 相似文献
69.
MA van Rossum TJ Fiselier MJ Franssen AH Zwinderman R ten Cate LW van Suijlekom-Smit WH van Luijk RM van Soesbergen NM Wulffraat JC Oostveen W Kuis PF Dijkstra CF van Ede BA Dijkmans 《Canadian Metallurgical Quarterly》1998,41(5):808-816
AIMS: To determine whether left ventricular volumes and ejection fractions calculated from single plane two-dimensional echocardiograms using the algorithm (0.85A2L) correlate with those calculated using the biplane Simpson's method, and whether small changes in volumes and ejection fraction occurring post-infarction could be detected from single-plane as well as from biplane two-dimensional echocardiograms. METHODS AND RESULTS: Serial two-dimensional echocardiograms were obtained in 371 patients from the DEFIANT II trial a mean of 2 days, 1 week and 6 months post-infarction. Single plane volumes from the apical four chamber and apical long axis correlated closely with biplane Simpson's left ventricular volumes. Both single-plane left ventricular volumes significantly over-estimated biplane Simpson's volumes. Biplane Simpson's ejection fractions were consistently slightly under-estimated from the single-plane images. Differences between biplane Simpson's and single-plane volumes increased independently with increasing left ventricular size and distortion. The small changes in left ventricular volumes and ejection fraction over time were as reliably detected from single plane as from biplane images. CONCLUSION: Single-plane left ventricular volumes over-estimate biplane Simpson's volumes and under-estimate ejection fraction, and these discrepancies are amplified in dilated hearts with abnormal shape. 相似文献
70.
T Hong MW King S Michielsen LW Cheung C Mary R Guzman R Guidoin 《Canadian Metallurgical Quarterly》1998,44(6):776-785
There have been reports suggesting that polypropylene (PP) monofilament sutures are associated with mechanical failure. To overcome this problem, a new monofilament suture made from polyvinylidene fluoride, under the trade name of Teflene, has been developed. Few studies have measured the in vitro properties of Teflene sutures, and those that have, have been limited to a few tensile properties of the straight suture such as tensile strength, elongation, and creep behavior. The in vitro performance properties of Teflene sutures were evaluated and compared with those of commercial sutures made from PP such as Prolene and Surgilene in four sizes, 2-0, 3-0, 4-0, and 5-0. The performance properties of sutures included both the physical properties of straight sutures, such as suture diameter, tensile strength, elongation, surface roughness, coefficient of friction, bending stiffness, and tissue drag, and the knot characteristics, such as knot pull strength, knot run-down, and knot security. Existing standard test methods and testing instruments were used if available to measure certain suture properties such as diameter, tensile strength, knot pull strength, and some physical properties. The other novel test methods and unique accessory devices needed to perform the tests for measuring tissue drag, knot run-down, coefficient of friction, and knot security were developed in the authors' laboratories, and the comparative results are reported for the first time. From the test results, Teflene sutures were found in general to possess equivalent characteristics to those of existing PP commercial sutures, but some differences also were observed, such as greater elongation and less knot run-down. These differences may give them a unique feel and handling performance, especially in terms of making a knot, sliding it into position, and causing less damage to adjacent tissue. 相似文献