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91.
PC Montecucchi A Anastasi R de Castiglione V Erspamer 《Canadian Metallurgical Quarterly》1980,16(3):191-199
The skin of the South American frog Phyllomedusa sauvagei contains a new active polypeptide, sauvagine, which does not belong to any of the peptide families hitherto described in the amphibian skin. The purification procedure involved several successive steps: dialysis, precipitation with ethanol and acetone, gel filtration and ion exchange chromatography. Two forms of sauvagine were separated. The major component (sauvagine I) was submitted to acid hydrolysis. The sauvagine molecule appeared to possess clear hydrophobic characteristics and to consist of a straight chain of 40 amino acid residues, among which the glutamyl-, aspartyl- leucyl- and isoleucyl-residues were particularly well represented. The elucidation of the amino acid sequence in the sauvagine molecule is in progress. 相似文献
92.
上网本
我办公室有办公用笔记本电脑,家里有台式PC,而华硕Eee PC 1000HE算是我的随身电脑。 相似文献
93.
AL Barry PC Fuchs C Thornsberry JC McLaughlin SG Jenkins DJ Hardy SD Allen 《Canadian Metallurgical Quarterly》1996,15(8):676-678
Three methods approved by the National Committee for Clinical Laboratory Standards for testing the susceptibility of anaerobic bacteria were used to evaluate the fluoroquinolone, trovafloxacin. The methods gave essentially comparable results with 126 anaerobes and with three quality control strains. A collaborative study defined the quality control range for trovafloxacin MICs. Trovafloxacin had good in vitro activity against the more common anaerobes (MIC 90 < = or 2.0 micrograms/ml). 相似文献
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We analyzed signal-averaged electrocardiograms (ECG) obtained in 50 patients with recent myocardial infarction (RMI: 25 anterior and 25 inferior) and 20 normal subjects to determine the relationship between the initial portion of the signal-averaged QRS complex and cardiac function and infarct size. We examined (1) the root mean square voltage (RMS10-40, microV), (2) the integration (A10-40, microV.msec) at 10-msec intervals over the first 40 msec of the signal-averaged QRS complex, and (3) the intervals (T) of the magnitude of the signal-averaged ECG achieved at 10-microV intervals over the first 40 microV (T10-40, msec). The mean RMS10-40 (p < 0.01) and A10-40 (A10, p < 0.05; A20-40, p < 0.01) were significantly lower and the T10-40 (p < 0.01) was significantly longer in RMI patients than in normal subjects. The RMS10-40 (p < 0.01) and A10-40 (p < 0.05) were significantly lower and the T10-40 (T10.20, p < 0.01; T30.40, p < 0.05) was significantly longer in patients with anterior RMI patients than in patients with inferior RMI. The A30 was correlated with the ejection fraction and total creatine kinase (CK) release in all patients (r = 0.73, and -0.78, respectively, p < 0.001). These results suggest that the A30 may be an important predictor of ventricular dysfunction and infarct size in patients with RMI. 相似文献
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PURPOSE: The aim of this study was to determine the concentration of interleukin-1 alpha in human embryo culture medium with or without oviductal cell coculture and to correlate the interleukin-1 alpha levels with pregnancy. METHODS: Culture media from 32 in vitro fertilization and embryo transfer cycles were assayed for interleukin-1 alpha by immunoassay technique. Human embryos were cultured in Earles' balanced salt solution supplemented with 15% preovulatory serum (sEBSS) in 16 of these cycles, while embryos in the rest of the cycles were cocultured with human oviductal cells in sEBSS. RESULTS: Both sEBSS and spent sEBSS after embryo culture contained low or undetectable levels of interleukin-1 alpha in the pregnant and nonpregnant cycles. On the other hand, oviductal cells significantly increased the amount of interleukin-1 alpha immunoreactivity in the conventional culture medium or coculture medium (P < 0.001, Mann-Whitney rank sum test). The concentrations of interleukin-1 alpha in the spent sEBSS after oviductal cell culture and after coculture with human embryos were 1.5 +/- 1.0 and 1.3 +/- 0.9 pg/ml, respectively. There was no difference in the interleukin-1 alpha concentration between the pregnant and the nonpregnant coculture cycles. CONCLUSIONS: These data showed that human oviductal cells produced interleukin-1 alpha immunoreactivity in a coculture system. However, this production could not be used as a marker for successful embryo implantation. 相似文献
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CR Deible P Petrosko PC Johnson EJ Beckman AJ Russell WR Wagner 《Canadian Metallurgical Quarterly》1998,19(20):1885-1893
For cardiovascular biomaterials, thrombosis, thromboembolism and vascular graft occlusion are believed to be precipitated by the adsorption of proteins containing adhesive ligands for platelets. Polyethylene-glycol-diisocyanate (PEG-diisocyanate, 3400 MW) may potentially react with protein amines to form molecular barriers on adsorbed proteins on biomaterials, thereby masking adhesive ligands and preventing acute surface thrombosis. To test this notion, PE, PTFE, and glass microconduits were pre-adsorbed with fibrinogen and treated with PEG-diisocyanate, non-reactive PEG-dihydroxyl, or remained untreated. Following perfusion of 111In-labeled platelets in whole human blood for 1 min (wall shear rate = 312 s(-1)), PEG-diisocyanate treated surfaces experienced 96% (PE), 97% (PTFE) and 94% (glass) less platelet deposition than untreated surfaces. Similar reductions were seen for PEG-diisocyanate versus PEG-dihydroxyl treatment. Low shear perfusions of plasma for 1 h prior to blood contact did not reduce the inhibitory effect of PEG-diisocyanate. Platelet adhesion onto collagen-coated glass coverslips and platelet deposition onto preclotted Dacron were also reduced by treatment with PEG-diisocyanate (93 and 91%, respectively). Protein-reactive PEG may thus have utility in forming molecular barriers on surface-associated proteins to inhibit acute thrombosis on cardiovascular biomaterials. 相似文献