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排序方式: 共有238条查询结果,搜索用时 15 毫秒
231.
R. K. Kumar 《Cellular and molecular life sciences : CMLS》1978,34(6):768-769
Summary Retrograde lymphatic permeation of the liver by a malignant neoplasm is an unusual phenomenon and has apparently not been reported with colonic carcinoma. This paper presents such a case; the features of the lesion are similar to those described for other primary sites.Acknowledgment. The author thanks the staff of the Department of Morbid Anatomy at St. Vincent's Hospital, Sydney, for their cooperation and assistance with this case. 相似文献
232.
Ishii KJ Kawagoe T Koyama S Matsui K Kumar H Kawai T Uematsu S Takeuchi O Takeshita F Coban C Akira S 《Nature》2008,451(7179):725-729
Successful vaccines contain not only protective antigen(s) but also an adjuvant component that triggers innate immune activation and is necessary for their optimal immunogenicity. In the case of DNA vaccines, this consists of plasmid DNA; however, the adjuvant element(s) as well as its intra- and inter-cellular innate immune signalling pathway(s) leading to the encoded antigen-specific T- and B-cell responses remain unclear. Here we demonstrate in vivo that TANK-binding kinase 1 (TBK1), a non-canonical IkappaB kinase, mediates the adjuvant effect of DNA vaccines and is essential for its immunogenicity in mice. Plasmid-DNA-activated, TBK1-dependent signalling and the resultant type-I interferon receptor-mediated signalling was required for induction of antigen-specific B and T cells, which occurred even in the absence of innate immune signalling through a well known CpG DNA sensor-Toll-like receptor 9 (TLR9) or Z-DNA binding protein 1 (ZBP1, also known as DAI, which was recently reported as a potential B-form DNA sensor). Moreover, bone-marrow-transfer experiments revealed that TBK1-mediated signalling in haematopoietic cells was critical for the induction of antigen-specific B and CD4(+) T cells, whereas in non-haematopoietic cells TBK1 was required for CD8(+) T-cell induction. These data suggest that TBK1 is a key signalling molecule for DNA-vaccine-induced immunogenicity, by differentially controlling DNA-activated innate immune signalling through haematopoietic and non-haematopoietic cells. 相似文献
233.
Xu SZ Sukumar P Zeng F Li J Jairaman A English A Naylor J Ciurtin C Majeed Y Milligan CJ Bahnasi YM Al-Shawaf E Porter KE Jiang LH Emery P Sivaprasadarao A Beech DJ 《Nature》2008,451(7174):69-72
Mammalian homologues of Drosophila melanogaster transient receptor potential (TRP) are a large family of multimeric cation channels that act, or putatively act, as sensors of one or more chemical factor. Major research objectives are the identification of endogenous activators and the determination of cellular and tissue functions of these channels. Here we show the activation of TRPC5 (canonical TRP 5) homomultimeric and TRPC5-TRPC1 heteromultimeric channels by extracellular reduced thioredoxin, which acts by breaking a disulphide bridge in the predicted extracellular loop adjacent to the ion-selectivity filter of TRPC5. Thioredoxin is an endogenous redox protein with established intracellular functions, but it is also secreted and its extracellular targets are largely unknown. Particularly high extracellular concentrations of thioredoxin are apparent in rheumatoid arthritis, an inflammatory joint disease that disables millions of people worldwide. We show that TRPC5 and TRPC1 are expressed in secretory fibroblast-like synoviocytes from patients with rheumatoid arthritis, that endogenous TRPC5-TRPC1 channels of the cells are activated by reduced thioredoxin, and that blockade of the channels enhances secretory activity and prevents the suppression of secretion by thioredoxin. The data indicate the presence of a previously unrecognized ion-channel activation mechanism that couples extracellular thioredoxin to cell function. 相似文献
234.
Lohmueller KE Indap AR Schmidt S Boyko AR Hernandez RD Hubisz MJ Sninsky JJ White TJ Sunyaev SR Nielsen R Clark AG Bustamante CD 《Nature》2008,451(7181):994-997
Quantifying the number of deleterious mutations per diploid human genome is of crucial concern to both evolutionary and medical geneticists. Here we combine genome-wide polymorphism data from PCR-based exon resequencing, comparative genomic data across mammalian species, and protein structure predictions to estimate the number of functionally consequential single-nucleotide polymorphisms (SNPs) carried by each of 15 African American (AA) and 20 European American (EA) individuals. We find that AAs show significantly higher levels of nucleotide heterozygosity than do EAs for all categories of functional SNPs considered, including synonymous, non-synonymous, predicted 'benign', predicted 'possibly damaging' and predicted 'probably damaging' SNPs. This result is wholly consistent with previous work showing higher overall levels of nucleotide variation in African populations than in Europeans. EA individuals, in contrast, have significantly more genotypes homozygous for the derived allele at synonymous and non-synonymous SNPs and for the damaging allele at 'probably damaging' SNPs than AAs do. For SNPs segregating only in one population or the other, the proportion of non-synonymous SNPs is significantly higher in the EA sample (55.4%) than in the AA sample (47.0%; P < 2.3 x 10(-37)). We observe a similar proportional excess of SNPs that are inferred to be 'probably damaging' (15.9% in EA; 12.1% in AA; P < 3.3 x 10(-11)). Using extensive simulations, we show that this excess proportion of segregating damaging alleles in Europeans is probably a consequence of a bottleneck that Europeans experienced at about the time of the migration out of Africa. 相似文献
235.
Santosh Kumar Prusty Pratap K. J. Mohapatra C. K. Mukherjee 《Systemic Practice and Action Research》2014,27(4):397-416
The Indian Shrimp Industry has exhibited an interesting phenomenon of fast growth in the early nineties (1990–1994), decline in the mid-nineties (1995–1997), and slow revival in the recent years (1997–2009). The cyclic behavior of the Industry, though, was much discussed in the literature, but no explanation regarding such behavior was explicitly discussed in the literature. The strategies following such behavior were mostly ad-hoc and symptomatic in nature. In this paper, we have analyzed the Industry’s past behavior using a systems approach and have developed the structure of the Industry in the form of a system archetype, which explained the cyclic behavior of the Industry. The system archetypical structure of the Industry was made keeping the existing system archetypes as the foundation. The system archetype developed here is generic enough to explain any growth-decline-revival behavior of an industry or organization. The archetype of Indian Shrimp Industry also helped us in designing sustainable strategies for the Industry that included controlling over-expansion in a shrimp farming zone and controlling pollution generation by each shrimp farm. 相似文献
236.
Kumar KA Sano G Boscardin S Nussenzweig RS Nussenzweig MC Zavala F Nussenzweig V 《Nature》2006,444(7121):937-940
Malaria infection starts when mosquitoes inject sporozoites into the skin. The parasites enter the blood stream and make their way to the liver where they develop into the exo-erythrocytic forms (EEFs). Immunization with irradiated sporozoites (IrSp) leads to robust protection against malaria infection in rodents, monkeys and humans by eliciting antibodies to circumsporozoite protein (CS) that inhibit sporozoite infectivity, and T cells that destroy the EEFs. To study the role of non-CS antigens in protection, we produced CS transgenic mice that were tolerant to CS T-cell epitopes. Here we show that in the absence of T-cell-dependent immune responses to CS, protection induced by immunization with two doses of IrSp was greatly reduced. Thus, although hundreds of other Plasmodium genes are expressed in sporozoites and EEFs, CS is a dominant protective antigen. Nevertheless, sterile immunity could be obtained by immunization of CS transgenics with three doses of IrSp. 相似文献
237.
Saran Debasis Kumar Atul Bathula Sivaiah Klaumünzer David Sahu Kisor K 《矿物冶金与材料学报》2022,29(7):1435-1452
238.
Saran Debasis Kumar Atul Bathula Sivaiah Klaumünzer David Sahu Kisor K 《矿物冶金与材料学报》2022,29(7):1435-1452