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11.
Outdoor culture of the thermophilic cyanobacterium Synechocystis aquatilis SI-2 with a vertical flat-plate photobioreactor (VFPP) was studied during the period of January to August of 1999 in the northern region of Japan (Kamaishi, Iwate, 39 degrees N, 142 degrees E). The aim of this study was to investigate the CO2 fixation ability of the VFPP device under various irradiation conditions. An average biomass productivity of over 30 g m(-2) day(-1), which corresponds to a CO2 fixation rate of 50 g m(-2) day(-1), was achieved during this period with a 192-l scale culture. The effects on biomass productivity of the light path, height of the reactor, cell concentration and irradiation were also investigated. Variation of the optimal cell concentration to achieve the highest productivity for outdoor operation is discussed. A cell concentration of 1-2 g l(-1) was found to be most suitable for the irradiation range of 1-12 MJ m(-2) day(-1) under the experimental conditions used. 相似文献
12.
Yosuke Andoh Takashi Kuramoto Norihide Yokoi Toshiro Maihara Kazuhiro Kitada Tadao Serikawa 《Mammalian genome》1998,9(4):287-293
To correlate rat genetic linkage maps with cytogenetic maps, we localized 25 new cosmid-derived simple sequence length polymorphism
(SSLP) markers and 14 existing genetic markers on cytogenetic bands of chromosomes, using fluorescence in situ hybridization
(FISH). Next, a total of 58 anchor loci, consisting of the 39 new and 19 previously reported ones, were integrated into the
genetic linkage maps. Since most of the new anchor loci were developed to be localized near the terminals of the genetic or
cytogenetic maps for each chromosome, the orientation and coverage of the whole genetic linkage maps were determined or confirmed
with respect to the cytogenetic maps. Thus, we provide here a new base for rat genetic maps.
Received: 9 September 1997 / Accepted: 11 November 1997 相似文献
13.
Follow-up testing of rodent carcinogens not positive in the standard genotoxicity testing battery: IWGT workgroup report 总被引:1,自引:0,他引:1
Kasper P Uno Y Mauthe R Asano N Douglas G Matthews E Moore M Mueller L Nakajima M Singer T Speit G;IWGT Workgroup 《Mutation research》2007,627(1):106-116
At the Plymouth Third International Workshop on Genotoxicity Testing in June 2002, a new expert group started a working process to provide guidance on a common strategy for genotoxicity testing beyond the current standard battery. The group identified amongst others "Follow-up testing of tumorigenic agents not positive in the standard genotoxicity test battery" as one subject for further consideration [L. Müller, D. Blakey, K.L. Dearfield, S. Galloway, P. Guzzie, M. Hayashi, P. Kasper, D. Kirkland, J.T. MacGregor, J.M. Parry, L. Schechtman, A. Smith, N. Tanaka, D. Tweats, H. Yamasaki, Strategy for genotoxicity testing and stratification of genotoxicity test results-report on initial activities of the IWGT Expert Group, Mutat. Res. 540 (2003) 177-181]. A workgroup devoted to this topic was formed and met on September 9-10, 2005, in San Francisco. This workgroup was devoted to the discussion of when it would be appropriate to conduct additional genetic toxicology studies, as well as what type of studies, if the initial standard battery of tests was negative, but tumor formation was observed in the rodent carcinogenicity assessment. The important role of the standard genetic toxicology testing to determine the mode of action (MOA) for carcinogenesis (genotoxic versus non-genotoxic) was discussed, but the limitations of the standard testing were also reviewed. The workgroup also acknowledged that the entire toxicological profile (e.g. structure-activity relationships, the nature of the tumor finding and metabolic profiles) of a compound needed to be taken into consideration before the conduct of any additional testing. As part of the meeting, case studies were discussed to understand the practical application of additional testing as well as to form a decision tree. Finally, suitable additional genetic toxicology assays to help determine the carcinogenic MOA or establish a weight of evidence (WOE) argument were discussed and formulated into a decision tree. 相似文献
14.
Okuno M Minami K Okumachi A Miyawaki K Yokoi N Toyokuni S Seino S 《American journal of physiology. Endocrinology and metabolism》2007,292(1):E158-E165
We recently found that pancreatic acinar cells isolated from normal adult mouse can transdifferentiate into insulin-secreting cells in vitro. Using two different animal models of type 1 diabetes, we show here that insulin-secreting cells can also be generated from pancreatic acinar cells of rodents in the diabetic state with absolute insulin deficiency. When pancreatic acinar cells of streptozotocin-treated mice were cultured in suspension in the presence of epidermal growth factor and nicotinamide under low-serum condition, expressions of insulin genes gradually increased. In addition, expressions of other pancreatic hormones, including glucagon, somatostatin, and pancreatic polypeptide, were also induced. Analysis by the Cre/loxP-based direct cell lineage tracing system revealed that these newly made cells originated from amylase-expressing pancreatic acinar cells. Insulin secretion from the newly made cells was significantly stimulated by high glucose and other secretagogues. In addition, insulin-secreting cells were generated from pancreatic acinar cells of Komeda diabetes-prone rats, another animal model of type 1 diabetes. The present study demonstrates that insulin-secreting cells can be generated by transdifferentiation from pancreatic acinar cells of rodents in the diabetic state and further suggests that pancreatic acinar cells represent a potential source of autologous transplantable insulin-secreting cells for treatment of type 1 diabetes. 相似文献
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We examined life history traits and spermathecal morphology of both sexual and thelytokous Schwiebea mite species to determine ecological and morphological attributes during the evolution of parthenogenesis in this lineage.
We reconstructed a molecular phylogeny of eight Japanese species using the internal transcribed spacer 1 (ITS1) of the ribosomal
DNA (rDNA) and compared the sex ratio, developmental period, and egg number (fecundity) of each species within a species group
by rearing them in the laboratory. Habitat preference was also analyzed from both collection and literature data. The reconstructed
molecular phylogeny suggested that parthenogenesis evolved independently multiple times in this lineage. There were three
clusters in the tree, in each of which the idiosoma, leg, setae, and spermathecal morphology of females was similar or identical;
this suggested that mites in the same cluster were sister species. There was no relationship between sexual mode and life
history traits or habitat preference. These results suggest that sexual and asexual species use different microhabitats. Because
S. similis (sexual), S. elongata (thelytokous), and S. estradai (thelytokous) were in the same cluster and spermathecae of the first two were similar while that of the last was distinctively
reduced, we hypothesized that speciation occurred in this order and that spermathecae are reduced and eventually lost during
the course of parthenogenetic evolution. 相似文献
18.
Norihide Hinomoto Masahiko Muraji Takashi Noda Toru Shimizu Kenjiro Kawasaki 《Biological Control》2004,31(3):642
We developed multiplex polymerase chain reaction methods to identify five Orius (Heteroptera: Anthocoridae) species that occur commonly in Japan: Orius sauteri, Orius minutus, Orius strigicollis, Orius nagaii, and Orius tantillus. The method amplified internal transcribed spacer 1 of the nuclear ribosomal DNA by using five primers simultaneously and produced species-specific banding patterns upon agarose gel electrophoresis. Reliability of the method was tested for 350 individuals of 23 strains, and consistent results were obtained. Dichotomous keys are also provided for easy and quick species identification. 相似文献
19.
Tactile displays provoke tactile sensations by artificially stimulating tactile receptors. While many types of tactile displays have been developed, electrotactile displays that exploit electric stimulation can be designed to be thin, light, flexible and thus, wearable. However, the high voltages required to stimulate tactile receptors and limited varieties of possible sensations pose problems. In our previous work, we developed an electrotactile display using a micro-needle electrode array that can drastically reduce the required voltage by penetrating through the high-impedance stratum corneum painlessly, but displaying various tactile sensations was still a challenge. In this work, we demonstrate presentation of tactile sensation of different roughness to the subjects, which is enabled by the arrangement of the electrodes; the needle electrodes are on the fingertip and the ground electrode is on the fingernail. With this arrangement, the display can stimulate the tactile receptors that are located not only in the shallow regions of the finger but also those in the deep regions. It was experimentally revealed that the required voltage was further reduced compared to previous devices and that the roughness presented by the display was controlled by the pulse frequency and the switching time, or the stimulation flow rate. The proposed electrotactile display is readily applicable as a new wearable haptic device for advanced information communication technology. 相似文献
20.
T. Sasaki Natalia A. Pronina M. Maeshima I. Iwasaki N. Kurano S. Miyachi 《Plant biology (Stuttgart, Germany)》1999,1(1):68-75
Abstract: The number and cross-sectional area of vacuoles in Chlorococcum littorale cells visualized with a differential interfer ence fluorescence microscope increased after their transfer from air to 40% CO2 . An immunological observation indicated that the level of subunit B of vacuolar H*ATPase also increased under 40% CO2 conditions. The activity of nitrate-sensitive ATP-ase associated with the vacuolar membrane was 2–fold higher in 40% CO2 -- grown cells than in air-grown cells. The effects of inhi bitors on the ATPase activity confirmed that these activities were derived from vacuolar-type H-ATPase. These results sug gest that vacuole development associated with that of vacuolar H+ -ATPase occurred during the acclimatization of C. littorale cells to extremely high CO2 conditions. 相似文献