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  • 1
    Electronic Resource
    Electronic Resource
    Production of carbon clusters by laser ablation of polymers in vacuum (2002)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 91 (2002), S. 2449-2454 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Time-of-flight mass spectrometry was used for analyzing ionic species produced by Nd:YAG laser ablation of polymers [polypropylene (PP), polyethylene (PE), and polytetrafluoroethylene] in vacuum. The temporal variation of the mass distribution after the laser irradiation was investigated. The target polymers were decomposed to almost atomic species by the laser irradiation. After the laser irradiation, significant temporal evolution of carbon cluster ions (CnHm+, CnHm−, and CnFm−) was observed. This result indicates that the cluster ions are produced from atomic species via gas-phase reactions in the ablation plume with no ambient gases. The mass spectra of Cn− and CnHm− obtained from the PP and PE targets suggest that even carbon clusters (C2k) are hydrogenated more efficiently than odd ones (C2k+1) to produce C2kHm. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1434548
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  • 2
    Electronic Resource
    Electronic Resource
    Surface production of CF, CF2, and C2 radicals in high-density CF4/H2 plasmas (2000)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 88 (2000), S. 5585-5591 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Surface production of CF, CF2, and C2 radicals in high-density CF4/H2 plasmas was examined using laser-induced fluorescence spectroscopy. No significant amount of surface production was observed in pure CF4 plasmas. The addition of H2 into CF4 plasmas enhanced the surface production of CFx and C2 from fluorocarbon film deposited on the chamber wall. The characteristics of the surface production in cw discharges are reported, in comparison with surface production in pulsed discharges. In addition, it has been found that the surface production rates are determined not by the partial pressure but by the flow rate of H2, suggesting the significant consumption of feedstock H2 in discharges. The surface production of CFx and C2 indicates that these radicals are not the precursors for the deposition of fluorocarbon film in the CF4/H2 plasma. The deposition mechanism of fluorocarbon film in the CF4/H2 plasma is discussed, taking into account the surface production of CFx and C2. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1319974
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  • 3
    Electronic Resource
    Electronic Resource
    Distributions of C2 and C3 radical densities in laser-ablation carbon plumes measured by laser-induced fluorescence imaging spectroscopy (2002)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 91 (2002), S. 4033-4039 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We measured temporal variations of the distributions of C2 and C3 radical densities in carbon plumes produced by laser ablation of graphite in ambient He gas. Laser-induced fluorescence imaging spectroscopy was used for the measurement. The temporal variations of total numbers of C2 and C3 contained in plumes were evaluated by integrating the density distributions. The experimental observations have shown that the gas-phase production of C2 is comparable to the direct production from the target, while C3 is mainly produced in gas phase by three-body reactions between C and C2. In addition, we have discussed a scenario for the temporal evolution of heavy clusters (Cn with n≥4). The present results are useful for understanding initial formation processes of carbon clusters in laser-ablation plumes. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1455151
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  • 4
    Electronic Resource
    Electronic Resource
    Characteristics of C3 radicals in high-density C4F8 plasmas studied by laser-induced fluorescence spectroscopy (2000)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 88 (2000), S. 6201-6206 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Spatial and temporal variations of C3 density in high-density octafluorocyclobutane (c-C4F8) plasmas were examined using laser-induced fluorescence spectroscopy. The C3 density varied slowly for a long time after the initiation of discharge, suggesting the importance of surface chemistry for the formation of C3. Hollow-shaped spatial distributions (the C3 density adjacent to the chamber wall was higher than that in the plasma column) were observed in the C3 density. This result indicates that C3 radicals are produced from fluorocarbon film on the chamber wall and are lost in the plasma column due to electron impact processes. The surface production of C3 was also observed in the afterglow for 1 ms after the termination of rf power. The decay time constant of the C3 density in the late (〉1 ms) afterglow, where the surface production of C3 stopped, was almost independent of discharge parameters, suggesting that the loss of C3 due to gas-phase reactions is negligible. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1321029
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  • 5
    Electronic Resource
    Electronic Resource
    047 
Allogeneic Transplantation of Genetically Modified Primate Embryonic Stem Cells (2004)
    Oxford, UK; Malden, USA : Blackwell Science Inc
    Wound repair and regeneration 12 (2004), S. 0 
    Details
    ISSN: 1524-475X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Aim: To examine the efficacy and safety of human embryonic stem (ES) cell-based therapies, allogeneic transplantation of monkey ES cells would be useful. We transplanted genetically marked monkey ES cells into the allogeneic fetus. Methods and Results: Cynomolgus ES cells were transduced once using a simian immunodeficiency virus-based lentivirus vector encoding the GFP gene driven by the CMV promoter at 1, 10 and 100 transducing units per cell. Five days posttransduction, 60, 80 and 90% of the cells expressed GFP, respectively, and the expression levels were stable for 5 months. GFP expression was still observed after embryoid-body formation. The gene-marked ES cells were transplanted into the cynomolgus fetus in the abdominal cavity (n = 2) or liver (n = 1) after the first trimester. The fetuses were delivered 1 month posttransplantation. Transplanted cell progeny were detected (∼1%) in multiple tissues by quantitative PCR and in situ PCR of the GFP sequence. No teratoma was found in the tissues. Conclusions: Cynomolgus ES cells can be engrafted in the allogeneic fetus. We are now trying to transplant cynomolgus ES cells differentiated to neural or hematopoietic lineage.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1067-1927.2004.abstractbi.x
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  • 6
    Electronic Resource
    Electronic Resource
    A measurement method of absolute hydrogen atom density in plasmas by (2+1)-photon laser-induced fluorescence spectroscopy (2001)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 72 (2001), S. 2298-2304 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A technique of (2+1)-photon laser-induced fluorescence (LIF) spectroscopy has been developed for measuring hydrogen atom density in plasmas. In this method, the following two-step excitation scheme is employed to excite ground-state H atoms to the 4p state. In the first step, H atoms at the ground (1s) state are excited to the 2s state by two photons at a wavelength of 243 nm. Subsequently, the 2s state is excited to the 4p state by the third photon at 486 nm in the second step. Fluorescence emission at 486 nm (4p→2s, Hβ line) is detected to determine the H atom density at the ground state. Since the wavelength used in the first-step excitation is the half of the wavelength used in the second-step excitation, one tunable laser with a system for second harmonic generation can be utilized in the measurement. The absolute density was evaluated by comparing the intensity of LIF emission from H with that from Xe at a known gas pressure. The present method is suitable for diagnostics of reactive plasmas since optical dissociation of molecules and radicals can be avoided because of the low photon energy of the laser radiation. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1367356
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  • 7
    Electronic Resource
    Electronic Resource
    Compositional analysis of root cementum and dentin after Er:YAG laser irradiation compared with CO2 lased and intact roots using Fourier transformed infrared spectroscopy (2002)
    Copenhagen : Munksgaard International Publishers
    Journal of periodontal research 37 (2002), S. 0 
    Details
    ISSN: 1600-0765
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The present study examines the dental root after Er:YAG laser irradiation, compared with CO2 lased and non-treated surfaces, using Fourier Transformed Infrared (FTIR) spectroscopy. Freshly extracted human teeth were irradiated by Er:YAG laser at an energy output of 40 mJ/pulse, 10 Hz(0.4 watts), with or without water coolant, and by CO2 laser at an energy output of 0.5 watts in continuous wave mode without coolant. The surfaces were chalky and smooth after irradiation by Er:YAG laser with water coolant, were charred and irregular after irradiation by Er:YAG laser without water coolant, and were completely carbonized after CO2 laser irradiation. The FTIR profiles from samples of the surfaces that were irradiated by Er:YAG laser with water coolant were similar to those from non-treated samples, except for a slight decrease on the OH and amide bands, which are mainly related to organic components. This decrease was observed to be extreme after CO2 laser irradiation and moderate after Er:YAG laser irradiation without coolant. The formation of new bands showing toxic substances was observed to a large extent after CO2 laser irradiation and to a smaller extent after Er:YAG laser irradiation without water coolant. In contrast, no such bands were detected after Er:YAG laser irradiation with water coolant. The present results show that these laser treatments selectively ablated more organic components than inorganic components and that Er:YAG laser irradiation with water coolant did not cause major compositional changes or chemically deleterious changes in either root cementum or dentin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1034/j.1600-0765.2002.00657.x
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  • 8
    Electronic Resource
    Electronic Resource
    Combined examination of p27Kip1, p21Waf1/Cip1 and p53 expression allows precise estimation of prognosis in patients with gastric carcinoma (2001)
    Oxford UK : Blackwell Science Ltd
    Histopathology 39 (2001), S. 0 
    Details
    ISSN: 1365-2559
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Combined examination of p27Kip1, p21Waf1/Cip1 and p53 expression allows precise estimation of prognosis in patients with gastric carcinoma Aims: In order to estimate the prognostic values of p27Kip1, p21Waf1/Cip1, and p53, alone and in combination, we investigated immunohistochemically the expression of p27Kip1, p21Waf1/Cip1, and p53 proteins in gastric carcinomas. Methods and results: The expression of p27Kip1, p21Waf1/Cip1, and p53 was immunohistochemically examined in 140 gastric carcinomas. Positive expression of p27Kip1 and p21Waf1/Cip1 correlated significantly with a favourable prognosis (P 〈 0.05), whereas, positive expression of p53 tended to correlate with poor prognosis. Multivariate survival analysis revealed that TNM stage of tumour (P 〈 0.001), lymph node state (P=0.005), and p27Kip1 expression (P=0.006) were independent prognostic factors. A striking stratification of mortality rate was found when patients were divided into four groups according to the expression of p21Waf1/Cip1 and p27Kip1. The mortality rate was higher in patients with both p21Waf1/Cip1- and p27Kip1-negative gastric carcinoma than in patients with one or both positive carcinomas (P 〈 0.01). In addition, if the four p21Waf1/Cip1/p27Kip1 groups were compared based on p53 status, p53+ cases tended to have a higher mortality rate than p53- cases. Conclusion: Our results suggest that low expression of both p27Kip1 and p21Waf1/Cip1 could be useful as markers of poorer prognosis, and the combined examination of p27Kip1, p21Waf1/Cip1 and p53 expression allows reliable estimation of prognosis for patients with gastric carcinoma.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2559.2001.01283.x
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  • 9
    Electronic Resource
    Electronic Resource
    Elemental diet modulates the growth of Clostridium difficile in the gut flora (2004)
    Oxford, UK : Blackwell Publishing Ltd
    Alimentary pharmacology & therapeutics 20 (2004), S. 0 
    Details
    ISSN: 1365-2036
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background and aims : Tube feeding is regarded as a risk factor for Clostridium difficile-associated diarrhoea. Recently, we reported that C. difficile toxin was frequently found in patients receiving an elemental diet. The present study was conducted to clarify whether elemental diets are associated with the growth of C. difficile in the gut flora.Methods : C. difficile was cultured for 72 h in various concentrations of elemental diet containing 3% thioglycollate, and the growth rate or activity of C. difficile was evaluated by Gram stain or by measuring optical density at 560 nm. Faecal samples from 10 healthy adults were cultured in elemental diet + 3% thioglycollate. RNA was extracted from faeces with glass powder, which can eliminate PCR inhibitors, and mRNA of C. difficile toxin B was measured by reverse transcription PCR.Results : Maximum OD560 value during culture in thioglycollate-containing elemental diet was 2.4 times higher than that in thioglycollate alone (P = 0.0163). Viability of C. difficile was decreased in thioglycollate but not in thioglycollate-containing elemental diet. Toxin B mRNA was detected in five faecal samples (50%) before culture and in all samples after culture.Conclusions : Our results suggest that an elemental diet can modulate the growth of C. difficile in the gut flora.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2036.2004.01969.x
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  • 10
    Electronic Resource
    Electronic Resource
    Glicentin, an active enteroglucagon, has a significant trophic role on the small intestine but not on the colon in the rat (2001)
    Oxford UK : Blackwell Science Ltd
    Alimentary pharmacology & therapeutics 15 (2001), S. 0 
    Details
    ISSN: 1365-2036
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Many experiments have indicated that the gut glucagons (enteroglucagons) are associated with cell proliferation in the small intestine. However, recent studies have failed to show trophic effects of glicentin (enteroglucagon) on the intestine.〈section xml:id="abs1-2"〉〈title type="main"〉Aims:To examine the effects of glicentin on intestinal proliferation in vivo in the rat.〈section xml:id="abs1-3"〉〈title type="main"〉Methods:Rats were established on total parenteral nutrition for 6 days. Four experimental groups were given daily doses of 1, 4, 20 and 80 μg/rat of glicentin via the jugular vein. Rats fed by total parenteral nutrition and rats fed chow ad libitum were used as controls. Tissues taken from the duodenum, jejunum, ileum and colon were fixed in Carnoy’s fluid and microdissected to determine the metaphase arrest scores and crypt fission ratios.〈section xml:id="abs1-4"〉〈title type="main"〉Results:The mean metaphase arrest scores per crypt of the small intestine were significantly increased in the rats given 4, 20 and 80 μg of glicentin. These responses were dose-dependent, and were most prominent in the ileum. Crypt fission of the ileum was significantly decreased in the 20 and 80 μg glicentin groups. Glicentin had no effects on proliferation or fission in the colon.〈section xml:id="abs1-5"〉〈title type="main"〉Conclusions:Glicentin is trophic to the rat small intestine, but not the colon.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2036.2001.01082.x
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