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991.
Immunization of cancer patients with tumor-specific antigenic peptides is currently being tested in several clinical studies. We have examined the induction of CTL responses in mice after various modalities of peptide vaccination, to explore protocols that could be applied to humans. Our first model antigen was P198, which results from a point mutation in a normal gene. While two immunizations with peptide P198 in SBAS-1c adjuvant induced measurable CTL responses in less than 10% of DBA/2 mice, the addition of IL-12 to the peptide adjuvant mixture resulted in high CTL responses in nearly all mice. This strong enhancing effect of IL-12 was observed with 1,000 and 300 units and decreased gradually as the doses were reduced to 30 units. When IL-12 was replaced by other cytokines acting on T cells or antigen-presenting cells, such as IFN-gamma, IL-2, IL-6, IL-7, GM-CSF or MCP-3, no significant enhancing effect was observed. The same effect of IL-12 was obtained with peptide P1A, which is a major tumor-specific antigen of mastocytoma P815 and is encoded by a gene that is specifically activated in tumors. 相似文献
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995.
D. Allan Drummond 《Current biology : CB》2009,19(17):R740-R742
996.
Microbiological and biotechnological characteristics of intensification of aerobic processing of organic waste have been reviewed, with a view for revealing two types of correlations: (1) between the quality of the composts obtained and the microorganisms involved in composting and (2) between physicochemical parameters and consumer properties of the composts. 相似文献
997.
The mesophilic and psychrotolerant microbiota of the air, soil, water, and bottom sediments of the Kinderlinskaya cave (South
Urals, Russia) and the factors affecting the structure of microbial communities were investigated. The pattern of microbial
distribution in soils was shown to depend on both the configuration of the cave and the level of recreational load. The lowest
numbers of bacteria and micromycetes were found in the poorly visited, difficult-to-access sites. Coliform bacteria were revealed
in all soil and sediment samples and in some water samples. Micromycetes belonged to 19 genera, with Geomyces pannorum as the dominant species. Air movement was shown to be the main factor affecting the density of the aerial microbiota. 相似文献
998.
999.
The Rho‐associated (ROCK) serine/threonine kinases have emerged as central regulators of the actomyosin cytoskeleton, their main purpose being to promote contractile force generation. Aided by the discovery of effective inhibitors such as Y27632, their roles in cancer have been extensively explored with particular attention focused on motility, invasion and metastasis. Recent studies have revealed a surprisingly diverse range of functions of ROCK. These insights could change the way ROCK inhibitors might be used in cancer therapy to include the targeting of stromal rather than tumour cells, the concomitant blocking of ROCK and proteasome activity in K‐Ras‐driven lung cancers and the combination of ROCK with tyrosine kinase inhibitors for treating haematological malignancies such as chronic myeloid leukaemia. Despite initial optimism for therapeutic efficacy of ROCK inhibition for cancer treatment, no compounds have progressed into standard therapy so far. However, by carefully defining the key cancer types and expanding the appreciation of ROCK's role in cancer beyond being a cell‐autonomous promoter of tumour cell invasion and metastasis, the early promise of ROCK inhibitors for cancer therapy might still be realized. 相似文献
1000.
The flowering time is the most susceptible period for primary infection of wheat heads byFusarium spp. During this period spores can be deposited into the opened wheat florets where they may later cause infections. We quantitatively
explored the relationship between variables related to the flowering process and the infection level byFusarium graminearum in single spikelets. We imitated open (chasmogamous) and closed (cleistogamous) flowering by injecting well-defined amounts
of spores into and between wheat florets. Applying the spores between the florets resulted in weaker disease symptoms and
significantly lower amounts ofFusarium mycotoxins. With larger numbers of spores, the disease symptoms became more pronounced and the mycotoxin amounts per spikelet
increased significantly.
Our results indicate that the probability of primary infection is approximately proportional to the number of spores reaching
the open florets during the flowering process. The breeding of wheat lines which flower partially or completely cleistogamously
might reduce theFusarium susceptibility in wheat. 相似文献