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921.
MI Matee EF Lyamuya E Simon EC Mbena C Kagoma LP Samaranayake F Scheutz 《Canadian Metallurgical Quarterly》1996,73(5):292-294
The present study, based on 158 HIV seropositives and 167 HIV seronegatives, demonstrates that saliva collected with the Omni-SAL device and tested with GACELISA (an IgG antibody capture ELISA) is an effective non-invasive alternative to serum for anti-HIV IgG antibody screening. The study also shows that a conventional serum Western blot kit can be used, with slight modifications, for confirmatory testing of saliva specimens. Collecting saliva with the Omni-SAL device had a very good acceptance rate among Tanzanian subjects, and although this diagnostic method is not yet known by the general public, 65% of the study participants preferred to give saliva instead of blood for HIV testing. 相似文献
922.
JF Delaloye S Leyvraz E Outcha Adjahoto J Bauer P De Grandi 《Canadian Metallurgical Quarterly》1996,19(2):204-206
We report two cases of metastatic non-functioning pancreatic endocrine tumour with very elevated plasma levels of alpha-fetoprotein. In these two cases, serial plasma levels of alpha-fetoprotein, initially normal, correlated well with hepatic tumour progression and were associated with fatal outcome. These results suggest that elevated plasma concentration of alpha-fetoprotein may be caused by metastatic pancreatic endocrine tumour and than alpha-fetoprotein serial measurement may be useful in prognostic evaluation. 相似文献
923.
Reflex sympathetic dystrophy, characterized by pain, swelling, vasomotor instability, and trophic changes in an extremity, has been infrequently described in patients with occult malignancy. Two cases of reflex sympathetic dystrophy associated with local tumor involvement are reported. Both patients had a history of cancer in clinical remission. Despite aggressive physical therapy measures, the patients' symptoms persisted. Workup of the first patient found an apical paravertebral mass in the lung; biopsy revealed recurrent breast carcinoma. In the second case, workup found an axillary mass contiguous with the lower brachial plexus. Biopsy revealed lymphoma, a second primary malignancy. In both cases, medical treatment of the tumor was instituted, with consequent improvement of hand and shoulder function. Both patients required prolonged hospitalization and multiple procedures that might have been avoided if malignancy had been suspected. Spontaneous development of reflex sympathetic dystrophy in patients with a history of cancer should alert the physician to the possibility of occult malignancy. 相似文献
924.
Gaidis M.C. Friedrich S. Segall K. Prober D.E. Szymkowiak A.E. Moseley S.H. 《Applied Superconductivity, IEEE Transactions on》1996,6(1):1-4
We report the development of Nb-Ta-Al-Al2O3-Al superconducting tunnel junction structures for high energy resolution and high efficiency X-ray detection. These devices utilize a Ta X-ray absorber with superconductor “bandgap engineered” quasiparticle trapping to improve charge collection. Experimental results at 0.3 K are presented, showing energy resolution of 102 eV full-width-half-maximum for 6 keV X-rays. Collected charge is in excess of 5×106 electrons. The absorption efficiency is better than 35%. Devices thermally cycle with no change in characteristics 相似文献
925.
Francis E. Powell Brian W. Brooks 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1993,57(1):65-71
Dimensionless material balance equations describing an uninhibited enzyme hydrolysis process in a semi-batch reactor (i.e. fed-batch reactor) are formulated; numerical solution of these equations provided concentration profiles of the enzyme-substrate complex by using published kinetic parameters. The unrestricted values obtained are compared with estimates based separately on the reaction steady state and stationary state assumptions. Results are discussed in terms of the enzyme/substrate inventory used and it is found that the reaction steady state is a satisfactory approximation only when this ratio is sufficiently small. The stationary state may be a better approximation at other values, particularly when enzyme is added to substrate or when an empty tank is being filled. Reaction yields from semi-batch and batch operations are compared. Processing takes longer in the semi-batch operations and complete conversions are only practical in this mode when enzyme is added to substrate. 相似文献
926.
A Ilnicka B Paw?owska J Czyzewska I G?ogowska J Korlak M Rodo K Bieganowska W Szirkowiec E Zdzienicka J Zaremba 《Canadian Metallurgical Quarterly》1996,30(1):65-75
The effects of 1-hydroxyethylidene-1, 1-bisphosphonate (HEBP) and two Chinese traditional (Kampo) medicines, Dai-saiko-to and Saiko-ka-ryukotsu-borei-to on spontaneous soft tissue (heart and tongue) mineralization in DBA/2NCrj mice were studied. These agents were given orally for 4 weeks to DBA/2NCrj mice. After 2 weeks of administration in the heart, 0.006 and 0.03% (w/v) HEBP decreased calcium content by 90 and 30%, respectively, while 0.27 and 2.7 mg/ml Dai-saiko-to reduced calcium content by 30 and 45%, respectively. Saiko-ka-ryukotsu-borei-to (0.27 mg/ml) reduced both calcium and phosphorus content by 50 and 35%, respectively. However, their inhibitory effects on the heart were not observed after 4 weeks of administration. The compounds delayed the onset of increases of bulk calcium and phosphorus content. In the tongue, at 4 weeks, 0.006 and 0.03% (w/v) HEBP reduced calcium content by 30 and 45%, respectively, while two Kampo medicines (at both concentrations used) significantly reduced the content of calcium (by 27-79%) and phosphorus (by 24-32%). These results strongly suggest that two Kampo medicines as well as HEBP may be useful in preventing and curing soft tissue calcification. 相似文献
927.
Compatibilization of poly(2,6-dimethyl (PPE) with 1,4 phenylene-ether) PA6 has been achieved in two steps: first, (PPE) was functionalized with N-methyl-4-nitro-phthalimide; then, functionalized PPE was allowed to react, by melt blending, with the amine end group of PA6, giving a trans-imidation product. The reaction path was followed by torque measurements in a Brabender apparatus and the products characterized by infrared (i.r.) and nuclear magnetic resonance (NMR) spectroscopy. The above PPE/PA6 blends, modified with a suitable rubbery component (Kraton G), showed a remarkable Izod impact strength value, compared to the uncompatibilized mixture (170 versus 30 Jm–1). The maximum impact values were obtained with 1.65% functionalized PPE. 相似文献
928.
A study is made of the efficiency with which filters average the output signal of a force transducer. The dependence of the
base of the filter on the pulse-tracking period is determined for two measurement regimes: with a specified number of discrete
signal readings; with a specified averaging time. The effect of the damping factor on the accuracy of the signal averaging
is also examined.
Translated from Izmeritel'naya Tekhnika, No. 6, pp. 52–56, June, 1996 相似文献
929.
E Donnadieu A Trautmann M Malissen J Trucy B Malissen E Vivier 《Canadian Metallurgical Quarterly》1994,269(52):32828-32834
The integrity of the T cell receptor complex (CD3-TCR) transduction machinery is central to T cell development and to T cell effector function. Molecular dissection of the multimeric CD3-TCR complex revealed that at least two associated polypeptides, CD3 zeta and CD3 epsilon, autonomously couple antigenic recognition event to early and late events of the intracytoplasmic activation cascade. A 18-amino acid motif based on a tandem YXXL stretch, the activation receptor homology sequence 1 (ARH-1) motif, is necessary and sufficient to the transducing properties of both CD3 zeta and CD3 epsilon. Stimulation of chimeric molecules made of ecto- and transmembrane domains of various cell surface proteins and intracytoplasmic domains of CD3 epsilon or CD3 zeta leads to an increase in the intracellular Ca2+ concentration ([Ca2+]i) in Jurkat cells. We describe here that a similar CD25/zeta chimeric molecule was unable to induce a detectable [Ca2+]i rise upon CD25 cross-linking once expressed in the murine thymoma BW-. A Ca2+ influx could, however, be triggered in BW- cells by thapsigargin, i.e. following depletion of Ca2+ stores. Somatic cell hybrids made from BW- and either thymocytes or mature lymph node T cells reconstituted the coupling of CD3 zeta to the Ca2+ signal via an ARH-1 motif-dependent pathway. However, pervanadate-induced Ca2+ mobilization, a phenomenon attributed to tyrosine phosphorylation, was impaired in BW-cells and reconstituted in hybridomas. In contrast to the Ca2+ response, IL-2 production was induced in both BW- and hybrids cells, which questions the functional relevance of [Ca2+]i augmentation in T cell activation. In conclusion, the properties of the BW- thymoma, which define a novel group of CD3 zeta transduction cell mutants, as well as its complementation by somatic cell fusion demonstrate that this cell line represents a useful model to dissect the signaling pathway that couples CD3 zeta to Ca2+ mobilization by genetic reconstitution. 相似文献
930.