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991.
992.
A cell line designated "HEPFT" was established from a human fallopian tubal hepatoid carcinoma. This line grew well without interruption for 13 months and was subcultivated over 35 times. The cells were spherical and polygonal in shape and showed neoplastic and pleomorphic features such as a bizarre aggregation of chromatin granules, an irregular thickening membrane and multiple large nucleoli. The cells formed epithelial colonies with a jigsaw puzzle-like arrangement and multilayering without contact inhibition. The cells contained moderate to abundant amounts of eosinophilic cytoplasm and were immunohistochemically positive for alpha-fetoprotein. The cells proliferated rapidly, and the population doubling time was about 45 h. The chromosome number showed a wide distribution of aneuploidy. The modal chromosome number was stable in the hyper triploid range and many marker chromosomes were observed. The culture cells produced bile and a large amount of lentil lectin-reactive alpha-fetoprotein. The recently developed bacterial artificial chromosome array comparative genomic hybridization facilitated detailed analysis with high resolution and sensitivity. Different profiles of genomic copy-number abnormalities were demonstrated in various chromosomal regions in HEPFT cells. 相似文献
993.
Female Cycnotrachelus roelofsi (Coleoptera: Attelabidae) construct two types of leaf roll, i.e., cut-off cradles (CCs) and suspended cradles (SCs), in which
to lay eggs; these cradles are generally constructed using older and younger leaves, respectively. We conducted two experiments
to determine whether the quality of cradle leaves affects egg and larval survival. In the first experiment, we severed all
SCs from a tree and placed them on the ground with unmanipulated CCs in the early breeding season. In the second experiment,
we resuspended all CCs in a tree with unmanipulated SCs in the late breeding season. We also compared leaf mass per area (LMA),
polyphenol content, and nitrogen content between the two cradle types to determine whether there were any differences in leaf
quality. Larval mortality, probably caused by cradle herbivory, was significantly greater in severed SCs than in intact CCs
in the early season, suggesting that leaf quality had a profound effect on larval mortality in the terrestrial microhabitat.
In contrast, larval mortality did not differ between resuspended CCs and intact SCs in the late season, suggesting that leaf
quality had little effect on larval mortality in the arboreal microhabitat. LMA was higher in CCs than in SCs, but there were
no differences in the nitrogen and polyphenol contents. These results suggest that cradles constructed using mature, tough
leaves were more effective against terrestrial cradle herbivores than those constructed using new, soft leaves. 相似文献
994.
Ribonuclease P (RNase P) is involved in the processing of the 5' leader sequence of precursor tRNA (pre-tRNA). We have found that RNase P RNA (PhopRNA) and five proteins (PhoPop5, PhoRpp21, PhoRpp29, PhoRpp30, and PhoRpp38) reconstitute RNase P activity with enzymatic properties similar to those of the authentic ribozyme from the hyperthermophilic archaeon Pyrococcus horikoshii OT3. We report here that nucleotides A40, A41, and U44 at helix P4, and G269 and G270 located at L15/16 in PhopRNA, are, like the corresponding residues in Esherichia coli RNase P RNA (M1RNA), involved in hydrolysis by coordinating catalytic Mg(2+) ions, and in the recognition of the acceptor end (CCA) of pre-tRNA by base-pairing, respectively. The information reported here strongly suggests that PhopRNA catalyzes the hydrolysis of pre-tRNA in approximately the same manner as eubacterial RNase P RNAs, even though it has no enzymatic activity in the absence of the proteins. 相似文献
995.
996.
Richard Baran Martin Robert Makoto Suematsu Tomoyoshi Soga Masaru Tomita 《BMC bioinformatics》2007,8(1):72
Background
Density plot visualizations (also referred to as heat maps or color maps) are widely used in different fields including large-scale omics studies in biological sciences. However, the current color-codings limit the visualizations to single datasets or pairwise comparisons. 相似文献997.
Rahmah Noordin Makoto Itoh Eisaku Kimura Rohana Abdul Rahman Balachandran Ravindran Rohela Mahmud Taniawati Supali Mirani Weerasooriya 《Filaria journal》2007,6(1):1-4
Background
Sustainable and equitable health programmes require a grounded understanding of the context in which they are being implemented. This socio-cultural understanding is pivotal for effective delivery of elimination programmes. Standardised valid methods are needed for gathering authentic socio-cultural insights. The currently recommended protocol for collecting Lymphatic Filariasis (LF) related socio-cultural data, while moving in the right direction, is inadequate. To collect data which provides an understanding of local health beliefs and practices, and communities' understanding of LF, techniques must be developed that are both valid and time efficient. An approach developed in the Pacific provides a basic snapshot of socio-cultural insights which are crucial to the development of relevant and sustainable health education and elimination programmes.Summary
The increasing interest in socio-cultural LF research presents a unique opportunity for coupling socio-cultural and bio-medical understandings of LF. To address the backlog in the socio-cultural sphere will require investment of time and effort to integrate valid qualitative approaches into current data collection methodologies. 相似文献998.
Youhei Tanaka Naohiro Hayashibara Tomoya Enokido Makoto Takizawa 《Cluster computing》2007,10(1):81-93
In this paper, we discuss how to realize fault-tolerant applications on distributed objects. Servers supporting objects can
be fault-tolerant by taking advantage of replication and checkpointing technologies. However, there is no discussion on how
application programs being performed on clients are tolerant of clients faults. For example, servers might block in the two-phase
commitment protocol due to the client fault. We newly discuss how to make application programs fault-tolerant by taking advantage
of mobile agent technologies where a program can move from a computer to another computer in networks. An application program
to be performed on a faulty computer can be performed on another operational computer by moving the program in the mobile
agent model. In this paper, we discuss a transactional agent model where a reliable and efficient application for manipulating objects in multiple computers is realized in the mobile agent
model. In the transactional agent model, only a small part of the application program named routing subagent moves around computers. A routing subagent autonomously finds a computer which to visit next. We discuss a hierarchical navigation
map which computer should be visited price to another computer in a transactional agent. A routing subagent makes a decision
on which computer visit for the hierarchical navigation map. Programs manipulating objects in a computer are loaded to the
computer on arrival of the routing subagent in order to reduce the communication overhead. This part of the transactional
agent is a manipulating subagent. The manipulation subagent still exists on the computer even after the routing subagent leaves the computer in order to hold
objects until the commitment. We assume every computer may stop by fault while networks are reliable. There are kinds of faulty
computers for a transactional agent; current, destination, and sibling computers where a transactional agent now exists, will move, and has visited, respectively. The types of faults are detected
by neighbouring manipulation subagents by communicating with each other. If some of the manipulation subagents are faulty,
the routing subagent has to be aborted. However, the routing subagent is still moving. We discuss how to efficiently deliver
the abort message to the moving routing subagent. We evaluate the transactional agent model in terms of how long it takes
to abort the routing subagent if some computer is faulty.
相似文献
Makoto TakizawaEmail: |
999.
Shizuyo Sutou Miho Kunishi Toshiyuki Kudo Pimprapar Wongsrikeao Makoto Miyagishi Takeshige Otoi 《BMC biotechnology》2007,7(1):44
Background
Since prion gene-knockout mice do not contract prion diseases and animals in which production of prion protein (PrP) is reduced by half are resistant to the disease, we hypothesized that bovine animals with reduced PrP would be tolerant to BSE. Hence, attempts were made to produce bovine PRNP (bPRNP) that could be knocked down by RNA interference (RNAi) technology. Before an in vivo study, optimal conditions for knocking down bPRNP were determined in cultured mammalian cell systems. Factors examined included siRNA (short interfering RNA) expression plasmid vectors, target sites of PRNP, and lengths of siRNAs. 相似文献1000.
Yosuke Shikama Yasusei Kudo Naozumi Ishimaru Makoto Funaki 《Journal of cellular physiology》2015,230(12):2981-2989