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991.
992.
DM Haig A Percival J Mitchell I Green D Sargan 《Canadian Metallurgical Quarterly》1995,45(3-4):221-236
An in vitro culture system is described which allows an analysis of the signals responsible for the survival, growth and functional maturation of afferent lymph dendritic cells (ALDC), a subpopulation of migrating dermal dendritic cells involved in antigen carriage and presentation to T-cells. Purified ALDC survived and grew for up to 30 days in lymph node conditioned medium and survived 14 days in recombinant ovine (rov) TNF-alpha whereas none were detected after 24 h in rov GM-CSF, rov IFN-gamma or rh M-CSF. However, when rov GM-CSF was added to cultures along with rov TNF-alpha, increased numbers of ALDC compared with input numbers (growth) were recorded on Days 14 and 21. In contrast, when 50-200 units ml-1 of rov IFN-gamma were added to cultures of ALDC along with TNF-alpha or rov TNF-alpha plus rov GM-CSF, cell survival and growth was inhibited. Antibody blocking studies confirmed the cytokine specificity of these effects. ALDC cultured in rov TNF-alpha or rov TNF-alpha plus rov GM-CSF retained MHC Class-II and ov CD-1 antigen expression and accessory function for autologous ov CD-4 T-cell proliferation, although at reduced levels compared with freshly isolated cells. Neither fresh nor cultured ALDC expressed coagulation factor XIIIa. 相似文献
993.
994.
995.
A. F. Lisovskii T. É. Gracheva E. S. Cherepenina I. V. Manzheleev 《Powder Metallurgy and Metal Ceramics》1988,27(6):445-449
Translated from Poroshkovaya Metallurgiya, No. 6(306), pp. 40–44, June, 1988. 相似文献
996.
997.
Vuong S.T. Lau A.C. Chan R.I. 《IEEE transactions on pattern analysis and machine intelligence》1988,14(3):384-393
The basic ideas underlying an Estelle-C compiler, which accepts an Estelle protocol specification and produces a protocol implementation in C, are presented. The implementation of the ISO (International Organization for Standardization) class-2 transparent protocol, using the semiautomatic approach, is discussed. A manual implementation of the protocol is performed and compared to the semiautomatic implementation. The semiautomatic approach to protocol implementation offers several advantages over the conventional manual one, including correctness and modularity in protocol implementation code, conformance to the specification, and reduction in implementation time. Finally, ongoing development of a new Estelle-C compiler is presented 相似文献
998.
The chromium content in foods is relatively low and the most foods have a content below 0.1 ppm. Only spices, cacao, cacao products, poppy and whole meal products contain higher contents. The often published high chromium content of corn germ oil could not be verified. We did not find any chromium enrichment in the entrails of a cow. In addition the chromium contents of each food are strong deviated. The analysed values were sometimes lower than in literature. We expect that the elder values are higher because of different contaminations in some cases. 相似文献
999.
Transfer coefficients behind a system of parallel channels and in an annular channel of complex form
As a result of measuring the temperature (concentration) field behind the source, the transfer coefficients are determined for flow in a tube behind a system of parallel channelsZ/d = 50) and in an annual channel of complex cross section.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 55, No. 6, pp. 897-902, December, 1988. 相似文献
1000.