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71.
Hiroshi Ishii Shizu Hayashi James C Hogg Takeshi Fujii Yukinobu Goto Noriho Sakamoto Hiroshi Mukae Renaud Vincent Stephan F van Eeden 《Respiratory research》2005,6(1):87
Background
Studies from our laboratory have shown that human alveolar macrophages (AM) and bronchial epithelial cells (HBEC) exposed to ambient particles (PM10) in vitro increase their production of inflammatory mediators and that supernatants from PM10-exposed cells shorten the transit time of monocytes through the bone marrow and promote their release into the circulation.Methods
The present study concerns co-culture of AM and HBEC exposed to PM10 (EHC-93) and the production of mediators involved in monocyte kinetics measured at both the mRNA and protein levels. The experiments were also designed to determine the role of the adhesive interaction between these cells via the intercellular adhesion molecule (ICAM)-1 in the production of these mediators.Results
AM/HBEC co-cultures exposed to 100 μg/ml of PM10 for 2 or 24 h increased their levels of granulocyte-macrophage colony-stimulating factor (GM-CSF), M-CSF, macrophage inflammatory protein (MIP)-1β, monocyte chemotactic protein (MCP)-1, interleukin (IL)-6 and ICAM-1 mRNA, compared to exposed AM or HBEC mono-cultures, or control non-exposed co-cultures. The levels of GM-CSF, M-CSF, MIP-1β and IL-6 increased in co-cultured supernatants collected after 24 h exposure compared to control cells (p < 0.05). There was synergy between AM and HBEC in the production of GM-CSF, MIP-1β and IL-6. But neither pretreatment of HBEC with blocking antibodies against ICAM-1 nor cross-linking of ICAM-1 on HBEC blocked the PM10-induced increase in co-culture mRNA expression.Conclusion
We conclude that an ICAM-1 independent interaction between AM and HBEC, lung cells that process inhaled particles, increases the production and release of mediators that enhance bone marrow turnover of monocytes and their recruitment into tissues. We speculate that this interaction amplifies PM10-induced lung inflammation and contributes to both the pulmonary and systemic morbidity associated with exposure to air pollution. 相似文献72.
Fujisaki S Takahashi I Hara H Horiuchi K Nishino T Nishimura Y 《Journal of biochemistry》2005,137(3):395-400
The chromosomal ispA gene encoding farnesyl diphosphate synthase of Escherichia coli was disrupted by inserting a neo gene cassette. The null ispA mutants were viable. The growth yield of the mutants was 70% to 80% of that of the wild-type strain under aerobic conditions, and was almost the same as the wild-type under anaerobic conditions. The levels of ubiquinone-8 and menaquinone-8 were both significantly lower (less than 13% and 18% of normal, respectively) in the mutants than in the wild-type. The undecaprenyl phosphate level in the mutants was modestly lower (40% to 70% of normal) than in the wild-type strain. Thus the synthesis of all-E-octaprenyl diphosphate, the precursor of ubiquinone-8 and menaquinone-8, was decreased more severely than that of Z,E-mixed undecaprenyl diphosphate, the precursor of undecaprenyl monophosphates, under the conditions where the synthesis of farnesyl diphosphate was decreased. The condensation of isopentenyl diphosphate with dimethylallyl diphosphate was detected in the cell-free extracts of the mutants, although it was 5% of that in the wild-type strain. A low level of farnesyl diphosphate seems to be synthesized in the mutants by other prenyltransferases such as octaprenyl diphosphate synthase or undecaprenyl diphosphate synthase. 相似文献
73.
Yasuhiro Ikeda Shin-lchi Itagaki Shigeki Tsutsui Yasuo Inoshima Masashi Fukasawa Keizo Tomonaga Yukinobu Tohya Ken Maeda Masami Mochizuki Takayuki Miyazawa Takeshi Mikami 《Microbiology and immunology》1997,41(5):431-435
Feline syncytial virus (FSV) was isolated from feline peripheral blood mononuclear cells of FSV-seropositive cats. When the susceptibility of feline T-lymphocytes to FSV was examined using three strains of FSV, FSV antigens were detected in the FSV-infected T-lymphoblastoid cells. Further, a diversity of biological properties, including replication kinetics and syncytia formation, was noted among the strains, and condensation of chromatin and the fragmentation of cellular DNA were observed in the infected cells. From these data, we conclude that FSV is lymphotropic and can induce apoptosis in the lymphocytes. 相似文献
74.
75.
Morphological and biochemical differentiation of limb bud cells cultured in chemically defined medium 总被引:4,自引:0,他引:4
Kenichiro Karasawa Koji Kimata Kenichiro Ito Yukinobu Kato Sakaru Suzuki 《Developmental biology》1979,70(2):287-305
When chick limb buds were isolated from stage 22–23 embryos and cultured in chemically defined medium “BGJb,” the explants grew and, after about 9 days, showed good chondrogenesis of recognizable cartilage segments. Cartilage-type proteoglycan (termed PCS-H) was not synthesized during early days of culture, but by Day 9, it became a major proteoglycan constituent of the tissue. Freshly dissociated limb bud cells, when plated as monodispersed cultures at a density of 7 × 106 cells/ml of BGJb, did not undergo chondrogenic differentiation and, instead, assumed the appearance of unhealthy or degenerated cells. During 9 days of culture, even though proteoglycans were synthesized, they were nevertheless of much smaller molecular size than PCS-H. When limb bud cells were cultured as a pellet containing 7 × 106 cells in 1 ml of BGJb, a more tightly packed aggregate of about 2 × 106 cells appeared in an inner region of the pullet during the first 24 hr of culture, and by Day 12 the aggregate had differentiated into a cartilage nodule surrounded by a thin layer of what appear to be ectodermal cells. As the conversion of aggregate into cartilage nodule progressed, newly formed proteoglycans gradually became more like cartilage-type proteoglycans, and by Day 12 they had many chemical and physical characteristics similar to those of the proteoglycans isolated from fully differentiated cartilages. The results indicate that the initial association of limb bud cells is an important factor for the chondrogenesis in BGJb and further suggest that the tight binding of the cell surfaces to one another may directly or indirectly stimulate the mechanism of synthesis of cartilage-type proteoglycans. 相似文献
76.
Kazuhiko Ishihara Makoto Kurihara Yukinobu Goso Hiroyoshi Ota Tsutomu Katsuyama Kyoko Hotta 《Glycoconjugate journal》1996,13(5):857-864
Eight monoclonal antibodies (MAbs), designated RGM21 RGM42, were generated against mucin purified from the rat gastric mucosa. By applying ELISA, all of these MAbs were proved to react not only with the purified mucin, but also with the oligosaccharide mixture obtained from the antigenic mucin by alkaline borohydride treatment. Treatment of the mucin-attached ELISA well with trypsin, sodium periodate or galactose oxidase prior to the addition of the MAb was applied to characterize these MAbs. Histochemical observation indicated that all these MAbs were able to stain the formalin fixed-paraffin embedded sections of the rat gastroduodenal mucosa. Although each of these MAbs reacted with distinct mucus-producing cells localized in particular regions of the gastroduodenal mucosa, their staining specificity could generally be classified into four groups. These MAbs might be useful for estimating the physiological and pathological changes of mucins in the gastric mucosa. 相似文献
77.
Murein-lipoprotein of Escherichia coli: a protein involved in the stabilization of bacterial cell envelope. 总被引:13,自引:0,他引:13
Hideho Suzuki Yukinobu Nishimura Seiichi Yasuda Akiko Nishimura Masao Yamada Yukinori Hirota 《Molecular & general genetics : MGG》1978,167(1):1-9
Summary Two independent mutants of Escherichia coli lacking murein-lipoprotein have been found. One mutant whose mutation was named lpo was subjected to detailed analyses. The absence of both found and unbound lipoproteins was shown by electrophoretic analysis of 14C-arginine labelled membrane proteins of the mutant. Nor was serologically cross-reacting material detected in the mutant by the Ouchterlony-method. Sequestering magnesium from mutant cell suspensions by ethylenediaminetetraacetic acid caused cell lysis, which was prevented in the presence of 0.5 M sucrose. Incubation in culture media at a very low level of magnesium resulted in the formation of blebs in the mutant. Examination of mutant cells by electron microscopy showed that the outer membrane of the mutant was uneven with small irregular protuberances, some of which pinched off forming vesicles of various sizes. Phosphotungstate used for negative-staining penetrated into the periplasmic space of the mutant cells. The mutants leaked a considerable fraction of their periplasmic enzymes. These physiological and morphological alterations in the lipoproteinless mutant suggest that murein-lipoprotein helps to maintain the outer envelope structure by connecting the outer membrane with murein so that the outer membrane may fulfil its physiological functions as a barrier to the environment. 相似文献
78.
Kenji Hamasaki Takehiko Yamanaka Koichi Tanaka Yukinobu Nakatani Nobusuke Iwasaki David S. Sprague 《Ecological Research》2009,24(3):597-605
To clarify the major factors affecting odonate assemblages in rural reservoir ponds among within-habitat environments, land
use around ponds and spatial autocorrelation, we surveyed odonate adults (Zygoptera and Anisoptera) in 70 study ponds in Ibaraki
Prefecture, Japan, during three sampling periods in 2005. Redundancy analyses (RDA) for these three factor groups were executed
to determine their strength in explaining the odonate species composition. Their relative contributions were also evaluated
by the method of variation partitioning. A total of 41 odonate species were recorded in the study ponds, and 24 of them, excluding
rare species, were used for our analysis. Summed effects including all three factor groups explained approximately 39% of
the variation in odonate species composition. We found that spatial autocorrelation was the most important, though the within-habitat
environment and land use had comparable effects. We conclude that spatial autocorrelation should be considered in this type
of analysis, though we could not clearly explain what caused such a spatial structure. Pond area and debris that had accumulated
at the bottom of ponds were selected as the within-habitat environment, and the forests and paddy fields around ponds were
selected for land use after the procedure of forward stepwise selection. These results suggest that the recent decrease of
forests around the ponds has had a negative effect on the odonate assemblages. 相似文献
79.
Mizushina Y Yagita E Kuramochi K Kuriyama I Shimazaki N Koiwai O Uchiyama Y Yomezawa Y Sugawara F Kobayashi S Sakaguchi K Yoshida H 《Archives of biochemistry and biophysics》2006,446(1):69-76
5-(Hydroxymethyl)-2-furfural (HMF), a pyrolysate of carbohydrate isolated from instant coffee (Coffea arabica L.), selectively inhibits the activities of mammalian DNA polymerase lambda (pol lambda) and terminal deoxynucleotidyltransferase (TdT) which are family X pols, in vitro. The compound influenced neither the activities of replicative DNA polymerases such as alpha, delta, and epsilon, nor even the activity of pol beta which is from the same family and thought to have a very similar three-dimensional structure to the pol beta-like region of pol lambda. Since parts of HMF such as furan, furfuryl alcohol, and 2-furaldehyde did not influence the activities of any enzymes tested, the substituted form of furan with a hyroxymethyl group and a formyl group might be important for the inhibition of pol lambda and TdT. The inhibitory effect of HMF on intact pol lambda (i.e., residues 1-575), a truncated pol lambda lacking the N-terminal BRCA1 C-terminus domain (133-575, del-1 pol lambda) and another truncated pol lambda lacking the N-terminal proline-rich region (245-575, del-2 pol lambda) was dose-dependent, and 50% inhibition was observed at a concentration of 26.1, 10.3, and 4.6 microM, respectively. The IC(50) value of HMF for TdT was the same as that for del-2 pol lambda (5.5 microM). The HMF-induced inhibition of both pol lambda and TdT activities was competitive with respect to both the DNA template-primer and the dNTP substrate. On the basis of these results, HMF was suggested to bind to the pol beta-like region of pol lambda and TdT. 相似文献
80.