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21.
22.
Human lung carcinoma tissues with histological types of adenocarcinoma, squamous cell and small cell carcinoma were investigated
for phospholipids. There were marked differences in the phospholipids between these lung carcinoma and normal lung tissue.
A marked decrease in saturated phosphatidylcholine (PC), predominantly the dipalmitoyl species, was noted in the carcinoma,
although they still contained 17–20% of the saturated classes. The lung carcinoma contained less phosphatidylglycerol (PG)
and lyso-bis-phosphatidic acid and more cardiolipin and phosphatidylinositol (PI) than the normal lung tissue. These alterations observed
in the lung carcinoma apppeared to show that they lose the characteristic feature of phospholipids in the lung tissue. The
differences in the lipid composition among different cell types of lung carcinoma were also noted. The squamous cell and small
cell carcinoma contained more triacylglycerol and relatively higher dienes I (monoenoic-monoenoic) and lower dienes II (saturated-dienoic)
of PG, respectively, as compared to adenocarcinoma. 相似文献
23.
Toshinobu Yoko Kanichi Kamiya Yoshihiro Ishino Sumio Sakka 《Journal of the American Ceramic Society》1984,67(8):154-C
The kinetics of copper-potassium ion exchange of potassium aluminosilicate glass have been investigated in molten CuCl at 550°C in air and nitrogen. The presence of oxygen dissolved in molten CuCl has a great effect on the Cu-K ion-exchange kinetics, i.e. ion exchange in nitrogen is controlled by the interdiffusion process of Cu+ and K+ in the glass, whereas ion exchange in air seems to be controlled by the Cu+ →Cu2+ oxidation reaction. 相似文献
24.
An T Nishio T Eguchi T Ono M Nomura A Akiyama K Hasegawa Y 《The Review of scientific instruments》2008,79(3):033703
Low-temperature ultrahigh vacuum frequency-modulation atomic force microscopy (AFM) was performed using a 1 MHz length-extension type of quartz resonator as a force sensor. Taking advantage of the high stiffness of the resonator, the AFM was operated with an oscillation amplitude smaller than 100 pm, which is favorable for high spatial resolution, without snapping an AFM tip onto a sample surface. Atomically resolved imaging of the adatom structure on the Si(111)-(7x7) surface was successfully obtained. 相似文献
25.
T. Yoshiie T. ItoH. Iwase Y. KanekoM. Kawai I. KishidaS. Kunieda K. SatoS. Shimakawa F. ShimizuS. Hashimoto N. HashimotoT. Fukahori Y. WatanabeQ. Xu S. Ishino 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(14):1740-1743
Changes in mechanical property of Ni under irradiation by 3 GeV protons were estimated by multi-scale modeling. The code consisted of four parts. The first part was based on the Particle and Heavy-Ion Transport code System (PHITS) code for nuclear reactions, and modeled the interactions between high energy protons and nuclei in the target. The second part covered atomic collisions by particles without nuclear reactions. Because the energy of the particles was high, subcascade analysis was employed. The direct formation of clusters and the number of mobile defects were estimated using molecular dynamics (MD) and kinetic Monte-Carlo (kMC) methods in each subcascade. The third part considered damage structural evolutions estimated by reaction kinetic analysis. The fourth part involved the estimation of mechanical property change using three-dimensional discrete dislocation dynamics (DDD). Using the above four part code, stress-strain curves for high energy proton irradiated Ni were obtained. 相似文献
26.
For a robot to cohabit with people, it should be able to learn people’s nonverbal social behavior from experience. In this
paper, we propose a novel machine learning method for recognizing gestures used in interaction and communication. Our method
enables robots to learn gestures incrementally during human–robot interaction in an unsupervised manner. It allows the user
to leave the number and types of gestures undefined prior to the learning. The proposed method (HB-SOINN) is based on a self-organizing
incremental neural network and the hidden Markov model. We have added an interactive learning mechanism to HB-SOINN to prevent
a single cluster from running into a failure as a result of polysemy of being assigned more than one meaning. For example,
a sentence: “Keep on going left slowly” has three meanings such as, “Keep on (1)”, “going left (2)”, “slowly (3)”. We experimentally tested the clustering performance of the proposed method against data obtained from measuring gestures
using a motion capture device. The results show that the classification performance of HB-SOINN exceeds that of conventional
clustering approaches. In addition, we have found that the interactive learning function improves the learning performance
of HB-SOINN. 相似文献
27.
We cloned two genes encoding DNA polymerases from the hyperthermophilic archaeon Pyrodictium occultum. The deduced primary structures of the two gene products have several amino acid sequences which are conserved in the alpha-like (family B) DNA polymerases. Both genes were expressed in Escherichia coli, and highly purified gene products, DNA polymerases I and II (pol I and pol II), were biochemically characterized. Both DNA polymerase activities were heat stable, but only pol II was sensitive to aphidicolin. Both pol I and pol II have associated 5'-->3' and 3'-->5' exonuclease activities. In addition, these DNA polymerases have higher affinity to single-primed single-stranded DNA than to activated DNA; even their primer extension abilities by themselves were very weak. A comparison of the complete amino acid sequences of pol I and pol II with two alpha-like DNA polymerases from yeast cells showed that both pol I and pol II were more similar to yeast DNA polymerase III (ypol III) than to yeast DNA polymerase II (ypol II), in particular in the regions from exo II to exo III and from motif A to motif C. However, comparisons region by region of each polymerase showed that pol I was similar to ypol II and pol II was similar to ypol III from motif C to the C terminus. In contrast, pol I and pol II were similar to ypol III and ypol II, respectively, in the region from exo III to motif A. These findings suggest that both enzymes from P. occultum play a role in the replication of the genomic DNA of this organism and, furthermore, that the study of DNA replication in this thermophilic archaeon may lead to an understanding of the prototypical mechanism of eukaryotic DNA replication. 相似文献
28.
F Kagitani Y Kuroiwa S Wakana T Shiroishi N Miyoshi S Kobayashi M Nishida T Kohda T Kaneko-Ishino F Ishino 《Canadian Metallurgical Quarterly》1997,25(17):3428-3432
We have established a systematic screen for imprinted genes using a subtraction-hybridization method with day 8.5 fertilized and parthenogenetic embryos. Two novel imprinted genes, Peg1/Mest and Peg3, were identified previously by this method, along with the two known imprinted genes, Igf2 and Snrpn. Recently three additional candidate imprinted genes, Peg5-7 , were detected and Peg5 is analyzed further in this study. The cDNA sequence of Peg5 is identical to Neuronatin, a gene recently reported to be expressed mainly in the brain. Two novel spliced forms were detected with some additional sequence in the middle of the known Neuronatin sequences. All alternatively spliced forms of Peg5 were expressed only from the paternal allele, confirmed using DNA polymorphism in a subinterspecific cross. Peg5/Neuronatin maps to sub-distal Chr 2, proximal to the previously established imprinted region where imprinted genes cause abnormal shape and behavior in neonates. 相似文献
29.
We report here an autopsy case of Binswanger's disease (BD) without hypertension and associated with cerebral infarction in the terminal stage. The female patient, who was 74 years old at the time of death, had initially demonstrated manic-depressive disorder-like mental disorder, followed by dementia and neurological deficits. A brain CT scan showed white matter low attenuation bilaterally and symmetrically. BD was clinically diagnosed despite the lack of hypertension. In the terminal stage, she suffered an infarction in the left anterior cerebral artery region, and died of pneumonia. Neuropathologically, we found the infarction of the left anterior cerebral artery region, demyelination, fibrillary gliosis, lacunae and arteriosclerosis of the small arteries and arterioles in the white matter. 相似文献