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221.
Summary The neural tissue of the monkey pineal contains both acetyl and butyryl cholinesterases. Acetylcholinesterase was localized in the cisternae of the nuclear membrane, rough endoplasmic reticulum, on the plasma membrane of the neurones, and on the axolemma of both non-myelinated and myelinated fibres. The enzyme was not found in the axosomatic or axo-dendritic synapses. It is therefore suggested that the pineal neurones have a cholinergic function rather than a cholinoceptive one.This study was supported by the WHO. 相似文献
222.
Summary Seeds ofSolanum surattense Burm. f. collected from areas of Bhopal (India) affected by methylisocyanate gas showed chromosome aberrations in root cells, and growth retardation and chlorophyll mutation of seedlings, the frequencies of which varied from one locality to another. 相似文献
223.
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
224.
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
225.
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
226.
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
227.
This study described the structural, dielectric, and piezoelectric behavior of Pb1?x Sr x [(Zr0.52Ti0.48)0.95(Mn1/3Nb2/3)0.05]O3 ceramics (PSZT-PMN, x = 0, 0.025, 0.050, and 0.075), prepared by a semi-wet route. X-ray diffraction, dielectric, and piezoelectric investigations were carried out to analyze the crystal structure. The relative dielectric constant and dielectric loss were both calculated as the functions of temperature. The room-temperature dielectric constant reaches a maximum for a Sr2+-modified PZT-PMN ceramic with an x value of 0.050, which corresponds to the morphotropic phase boundary (MPB). Raman spectroscopy studies also confirm the existence of this MPB for x = 0.050. The piezoelectric strain coefficients (d 33) value shows a maximum response for this composition. In addition, the phase transition temperature decreases significantly when the Sr2+ concentration increases in the PZT-PMN ceramics. 相似文献
228.
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