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71.
K. Itoh 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1977,30(1):89-105
Summary Direct projections from the pretectum in the cat were investigated by means of the Nauta-Gygax and the Fink-Heimer method in an attempt to identify the morphological substrates subserving possible neural mechanisms involved in visual behaviour and reflexes.Degeneration in the diencephalon was found ipsilaterally in the nucleus limitans, lateral pulvinar nucleus, lateral posterior nucleus, lateral dorsal nucleus, dorsal and ventral lateral geniculate nuclei, centre medianparafascicular complex, central medial nucleus, paracentral nucleus, central lateral nucleus, ventroanterior and ventrolateral nuclear complex, zona incerta, H field of Forel and the reticular nucleus. The pretectal fibers projecting to the ventral lateral geniculate nucleus appeared to be topically organized.In the midbrain, the pretectal fibers were observed to terminate ipsilaterally within the superior colliculus, nucleus of Darkschewitsch, dorsolateral portion of the red nucleus, lateral terminal nucleus of the accessory optic tract and the reticular formation, and bilaterally within the central gray, interstitial nucleus of Cajal and the rostral portion of the nucleus of Edinger-Westphal. Degeneration in the superior colliculus was marked in laminae II, III and IV. The fibers arising from more anterior part of the pretectum appeared to be distributed more medially in laminae II and III.The pretectopontine fibers terminated ipsilaterally in the paramedial and the dorsolateral pontine nuclei as well as the reticular formation. In the inferior olivary complex, degeneration was found in caudal levels of the dorsal cap and -nucleus, and additionally in the rostral portion of the dorsal accessory olive. 相似文献
72.
应用模糊极小极大神经网络研究了化合物复杂结构和性能(QSAR)之间的关系,用该法进行几组化合物致癌的识别,结果优于线性回归的方法,对此作出一些分析。 相似文献
73.
Makino S Miyamoto T Nakajima S Kabe J Baba M Mikawa H Furusho M Fukuda K Nakagawa T Naitou H 《Allergy》2000,55(2):135-140
BACKGROUND: In Japan in 1993, the Japanese Society of Allergology (JSA) developed guidelines for diagnosis and management of asthma (JGL), which were based on the concept that asthma is a chronic inflammatory disorder of the airway. METHODS: This survey study was intended to investigate the recognition and utilization of JGL among physicians who had treated asthma. The survey comprised two methods: a quantitative mail survey and a qualitative door-to-door survey conducted by trained interviewers. RESULTS: In the mail survey, a total of 1028 physicians responded; 552 members of the JSA and 476 nonmembers. Ninety-four percent of JSA members were aware of adult asthma management guidelines, while 53% of nonmembers were aware of them. Although approximately half of the physicians, both members and nonmembers, found differences between the asthma management policies in JGL and their previous policies, most of them utilized JGL once they read it. In the qualitative door-to-door survey, 80-90% of physicians evaluated JGL as good after they read it. CONCLUSIONS: JGL was recognized and utilized by most JSA members, but only half of nonmember physicians were aware of JGL, although they utilized JGL after they read it. Further action to implement JGL among nonspecialist physicians is needed to improve management of asthma. 相似文献
74.
Masahito Katoh Yasushi Itoh Kazumasa Ogasawara Kiichi Kajino Hiroki Nishihori Akio Takahashi Naoto Matsuki Kazuya Iwabuchi Takato O. Yoshida Robert A. Good Kazunori Ono 《European journal of immunology》1996,26(5):976-980
In a previous study, we identified T cell receptor and major histocompatibility complex (MHC) contact sites on the pigeon cytochrome c p43-58 peptide. Positions 46 and 54 of p43-58 were shown to be the MHC-binding sites. Specific amino acids were identified on the MHC-binding sites which bound to the relevant I-A molecule. In the present study, using NOD (I-Ag7) mice, we established a T cell hybridoma, NOE33-1-2, specific for a p43-58 analog 46R50E54A with arginine (R) and alanine (A) at positions 46 and 54, respectively. Interestingly, NOE 33-1-2 recognized 46R50E54A in the presence of not only I-Ag7, but also I-Ad, s, u and v. In contrast to previous reports that promiscuous T cells were able to recognize peptide antigens with various HLA-DR or I-E molecules consist of monomorphic α and polymorphic β chains, the promiscuous T cell clone NOE33-1-2 recognized peptides with various I-A molecules lacking the monomorphic chain. 相似文献
75.
Three monkeys with travel vision and 5 controls were observed with their mothers during the first 6 months of age and then for another 3 months after they had been placed in social isolation. In the home cage, the experimental animals did not differ from controls except that two held a hand before their eyes in a stereotyped fashion not previously reported for animals. In an unfamiliar environment the blind animals did not look at an observer, threatened less than normal, and were awkward in moving around. Animals who held hands before eyes tended to approach a flickering visual stimulus. 相似文献
76.
Bannerman DM Lemaire M Yee BK Iversen SD Oswald CJ Good MA Rawlins JN 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,142(3):395-401
Although a number of studies have implicated the hippocampal formation in social recognition memory in the rat, a recent study in this laboratory has demonstrated that selective cytotoxic lesions, confined to the hippocampus proper (encompassing the four CA subfields and the dentate gyrus), are without effect on this behaviour. This finding suggests that the hippocampus proper does not subserve social recognition memory in the rat, but does not preclude the possibility that other areas of the hippocampal formation, such as the entorhinal cortex or subiculum, could support this form of learning. The present study addressed this issue by examining the effects of selective cytotoxic retrohippocampal (RHR) lesions (including both the entorhinal cortex and subiculum) on social recognition memory in the rat. RHR lesions produced a mild social recognition memory impairment, although lesioned animals still displayed a reduction in investigation time between the first and second exposure to the juvenile. This result is consistent with other studies which have implicated the retrohippocampal or parahippocampal area in olfactory recognition memory processes. It also suggests, however, that other areas, out with the retrohippocampal region, are also likely to play an important role in social recognition memory. 相似文献
77.
78.
The properties of cells of the striate visual cortex (V1) have been studied in the normal adult sheep and in new-born lambs without visual experience, the majority of cells in the lamb are orientation specific, but 20% are non-oriented compared to only 3% cells in the adult. In the lamb there was little or no facilitation of binocularly-driven cells by simultaneous stimulation of both receptive fields. Cells which responded only to binocular stimulation of particular disparities ('obligate binocular' cells) were rarely encountered. In the adult, 15% of the sample were obligate binocular cells and a further 28% showed binocular facilitation. Simple and complex receptive fields were found in similar proportions in both new-born lambs and adult sheep. End-stopped cells comprised 17% of the sample in adults but only 2% in the lambs. Direction sensitive cells were found more frequently in the sheep (21% of cells) than in the lamb (4% of cells). It is concluded that facilitatory processes in binocular cells and inhibitory mechanisms generally, seem much less developed in the lamb. 相似文献
79.
Evans DL Kaur H Leary J Praveen K Jaso-Friedmann L 《Developmental and comparative immunology》2005,29(12):1049-1064
Nonspecific cytotoxic cells (NCC) are the first identified and most extensively studied killer cell population in teleosts. NCC kill a wide variety of target cells including tumor cells, virally transformed cells and protozoan parasites. The present study identified a novel evolutionarily conserved oligodeoxynucleotide (ODN) binding membrane protein expressed by channel catfish (Ictalurus punctatus) NCC. Peptide fingerprinting analysis of the ODN binding protein (referred to as NCC cationic anti-microbial protein-1/ncamp-1) identified a peptide that was used to design degenerate primers. A catfish NCC cDNA library was used as template with these primers and the PCR-amplified product was sequenced. The translated sequence contained 203 amino acids (molecular mass of 22,064.63 Da) with characteristic lysine rich regions and a pI=pH 10.75. Sequence comparisons of this protein indicated similarity to zebrafish (51.2%) histone family member 1-X and (to a lesser extent) to trout H1. A search of EST databases confirmed that ncamp-1 is also expressed in various tissues of channel catfish as well as zebrafish. Inspection for signature repeats in ncamp-1 and comparisons with histone-like peptides from different species indicated the presence of multiple lysine based motifs composed of AKKA or PKK repeats. The novel protein was cloned, expressed in E. coli and the recombinant was used to generate rabbit anti-serum. The recombinant ncamp-1 bound GpC and CpG ODNs and was detected with homologous anti-ncamp-1 polyclonal antibodies. Western blots of NCC membranes using anti-ncamp-1 serum detected a 29 kDa protein. Binding competition experiments demonstrated that anti-ncamp-1 antibodies and GpC bound to the same protein on NCC. Two different truncated forms of ncamp-1 as well as the full-length recombinant protein exhibited anti-microbial activity. The present study demonstrated the expression by NCC of a new membrane protein that may participate in the recognition of bacterial DNA and as such participate in innate anti-microbial immune responses in teleosts. 相似文献
80.
Sabine Siegemund Nicole Schütze Marina A. Freudenberg Manfred B. Lutz Reinhard K. Straubinger Gottfried Alber 《Immunobiology》2008,212(9-10):739-750
Induction of the interleukin-12 (IL-12) cytokine family comprising IL-12, IL-23, IL-27, and IL-12p40 by intracellular pathogens is required for orchestration of cell-mediated immune responses. Macrophages (MΦ) have been shown to be a source of IL-12 following TLR4-dependent activation by Salmonella (S.). In this study another antigen-presenting cell type, the conventional dendritic cell (cDC), was analyzed and its cytokine responses compared with those of MΦ. We generated bone marrow-derived conventional dendritic cells (BMDC) and macrophages (BMMΦ) by incubating murine bone marrow cells with supernatants containing granulocyte/macrophage colony-stimulating factor (GM-CSF) or macrophage colony-stimulating factor (M-CSF), respectively. Stimulation of BMDC and BMMΦ with S. enterica serovar Enteritidis (SE) or LPS resulted in the release of IL-12 and IL-23 by BMDC but not by BMMΦ. Furthermore, BMDC secreted approx. 20-fold more IL-12p40 and IL-27p28 than BMMΦ. However, BMDC and BMMΦ produced similar levels of IL-10. Using BMDC originating from wild-type (wt), TLR2def and TLR4def mice, we show that in BMDC the induction of IL-12, IL-23, and IL-27p28 by SE is dependent on TLR4, whereas low-level production of p40 is also mediated by pattern recognition receptors (PRR) other than TLR4. Interestingly, LPS- and SE-provoked responses of BMDC were remarkably similar indicating that LPS is the primary danger molecule of SE. Taken together, our results point to cDC rather than MΦ as the major producers of the IL-12 family members during in vitro infection with SE. The mechanisms of recognition of SE, however, appear to be the same for cDC and MΦ 相似文献