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排序方式: 共有785条查询结果,搜索用时 15 毫秒
71.
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M Varma DL Rudolph M Knuchel WM Switzer KG Hadlock M Velligan L Chan SK Foung RB Lal 《Canadian Metallurgical Quarterly》1995,33(12):3239-3244
Immunoassays based on the highly immunogenic transmembrane protein of human T-cell lymphotropic virus type 1 (HTLV-1) (protein 21c) are capable of detecting antibodies in all individuals infected with HTLV-1 and HTLV-2. However, because of antigenic mimicry with other cellular and viral proteins, such assays also have a large proportion of false-positive reactions. We have recently identified an immunodominant epitope, designated GD21-I located within amino acids 361 to 404 of the transmembrane protein, that appears to eliminate such false positivity. This recombinant GD21-I protein was used in conjunction with additional recombinant HTLV type-specific proteins and a whole virus lysate to develop a modified Western blot (immunoblot) assay (HTLV WB 2.4). The sensitivity and specificity of this assay were evaluated with 352 specimens whose infection status was determined by PCR assay for the presence or absence of HTLV-1/2 proviral sequences. All HTLV-1-positive (n = 102) and HTLV-2-positive (n = 107) specimens reacted with GD21-1 in the HTLV WB 2.4 assay, yielding a test sensitivity of 100%. Furthermore, all specimens derived from individuals infected with different viral subtypes of HTLV-1 (Cosmopolitan, Japanese, and Melanesian) and HTLV-2 (IIa0, a3, a4, IIb1, b4, and b5) reacted with GD21-I in the HTLV WB 2.4 assay. More importantly, HTLV WB 2.4 analysis of 81 PCR-negative specimens, all of which reacted to recombinant protein 21e in the presence or absence of p24 and p19 reactivity in the standard WB assay, showed that only two specimens retained reactivity to GD21-I, yielding an improved test specificity for the transmembrane protein of 97.5%. None of 41 specimens with gag reactivity only or 21 HTLV-negative specimens demonstrated reactivity to GD21-I. In an analysis of additional specimens (n = 169) from different geographic areas for which PCR results were not available, a substantial increase in the specificity of GD21-I detection was demonstrated, with no effect on the sensitivity of GD21-I detection among specimens from seropositive donors. Thus, the highly sensitive, GD21-I-based HTLV WB 2.4 assay eliminates the majority of false-positive transmembrane results, thereby increasing the specificity for serologic confirmation of HTLV-1 and HTLV-2 infections. 相似文献
74.
We describe here one instance of an acute occlusion of an angioplastied LAD coronary artery occurring during a treadmill stress test performed 2 d after the procedure. The occlusion occurred during the recovery period after a reasonably high level of stress was achieved without evidence of ischaemia. Similar instances described in the literature are summarized and discussed. In the light of these data, it might be prudent to avoid early post-PTCA exercise stress testing. 相似文献
75.
76.
Harbans Lal 《Drug development and industrial pharmacy》1979,5(2):133-149
Tools of Drug Development
Drug development is the foremost objective of most pharmacologists in the pharmaceutical companies and some pharmacologists in the other research institutions. To meet this objective, thousands of new chemical compounds must be evaluated in order to discover one which can be safely employed in the treatment of human illness. Such evaluation requires an enormous number of experimental subjects specially prepared for this purpose. Since use of human patients for initial screening of new chemicals is not feasible one must depend on laboratory animals that can be used repeatedly and extensively. 相似文献
Drug development is the foremost objective of most pharmacologists in the pharmaceutical companies and some pharmacologists in the other research institutions. To meet this objective, thousands of new chemical compounds must be evaluated in order to discover one which can be safely employed in the treatment of human illness. Such evaluation requires an enormous number of experimental subjects specially prepared for this purpose. Since use of human patients for initial screening of new chemicals is not feasible one must depend on laboratory animals that can be used repeatedly and extensively. 相似文献
77.
Ableitung eines Modells der ideal assoziierten Mischung unter Berücksichtigung einer elektrolytischen Dissoziation für flüssige Oxide. Behandlung von allgemeinen Gesetzmäβigkeiten der ideal assoziierten Mischung für binäre Silicatsysteme und Oxidsysteme. Überprüfung der Brauchbarkeit des Modells am Beispiel der Systeme Blei(II)-oxid–Siliciumdioxid bei 1100 °C und Calciumoxid–Eisen(II)-oxid bei 1600 °C. Berechnung der Anteile der in unterschiedlichen Komplexen vorhandenen Elemente und der Aktivitäten der Molekularkomponenten. 相似文献
78.
Behandlung von molekularer Schlackentheorie, Ionentheorie der Schlacke und elektrochemische Vorstellungen bei Schlackenungleichgewichten. Definition eines pO-Wertes in Analogie zum pH-Wert als Maβ für den Basengrad der Schlacke. Kennzeichnung des sauren und basischen Verhaltens von Oxyden durch ihre pO-Werte. Erläuterung des Zusammenhanges zwischen dem Redoxpotential von Schlacken und dem pO-Wert. 相似文献
79.
80.
V. K. Raizada V. S. Tripathi Darshan Lal G. S. Singh C. D. Dwivedi A. K. Sen 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1993,56(3):265-270
Butyraldehyde is an important chemical for many industrial applications, especially in the production of polyvinylbutyral. A systematic study of its synthesis by catalytic dehydrogenation of butanol, using zinc oxide as catalyst has been carried out. The effect of the method of preparation of zinc oxide on its catalytic activity for the title reaction has also been studied. The optimum conditions for maximum yield have been worked out and on the basis of secondary electron micrograms the reasons for higher activity/selectivity in the case of zinc oxide calcined from zinc hydroxide is attributed to the presence of hexagonal morphology. A kinetic study for the best zinc oxide catalyst has been carried out and the rate equation has been determined. 相似文献