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Chinese medical journal 09/2009; 122(17):2067-70. · 0.86 Impact Factor
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ABSTRACT: To evaluate the advantages of percutaneous radiofrequency ablation (PRFA) therapy with contralateral single lung ventilation (SLV) for liver carcinoma in the hepatic dome (LCHD).
The clinical data of 10 patients (the SLV group) with LCHD consecutively treated from January to December 2006 were retrospectively analyzed. And another 10 cases (the control group) with LCHD treated from January 2004 to December 2005 were selected with a strict inclusion criterion for compared test according to rules of same diagnosis, similar tumor bulk and site, same sex, similar age and liver function. The patients' ages and tumor diameters of the 2 groups were compared with t-test and the rates of complications and incomplete tumor ablation were compared with chi2-test.
There was no statistical difference in ages and tumor diameters between the 2 groups (P > 0.05). The average number of radiofrequency ablation needle punctures in the SLV group was significantly less than the control group (3.4 +/- 0.4 vs. 6.1 +/- 0.8, P < 0.01). There was no bronchial intubation related complications like hypoxemia, atelectasis, lung infection and no puncture related complications like pneumothorax, hemothorax, hemoperitoneum and bile leakage in the SLV group. Two cases in the control group had complications including pneumothorax (n = 1) and pleural effusion (n = 1). There was no mortality in the 2 groups. Though the rate of incomplete tumor necrosis in the SLV group was not statistically lower than that in the control group (10% vs. 40%), the occurrence rate of the undesirable event (complication and incomplete tumor necrosis) of the SLV group was significantly lower than that of the control group (10% vs. 60%, P < 0.05). The durations and costs of operating procedure were not significantly different between the 2 groups.
Left SLV makes PRFA for LCHD more efficient, effective and safe.
Zhonghua wai ke za zhi [Chinese journal of surgery] 10/2007; 45(17):1179-81.
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ABSTRACT: Varied temperature photoemission study is performed to investigate the quantum size effects on the thermal property of atomically flat Pb films grown on Si(111). The binding energies of the quantum well states for the films with thicknesses from 10 to 24 ML exhibit a linear increase with increasing temperature from 75 to 270 K. Under free electron approximation, thermal expansion coefficients of the thin films are determined, which manifest a large enhancement and oscillation behavior. The large enhancement is interpreted by a model based on the quantum confinement along the film normal direction. The oscillation is shown to be closely related to the structural instability and is a result of the formation of the quantized electronic states in thin films.
Applied Physics Letters 02/2007; 90(9):093120-093120-3. · 3.84 Impact Factor
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ABSTRACT: Ultrahigh vacuum atomic force microscopy is employed to measure the adhesive force of atomically flat (111) oriented Pb island on Si (111) surface at low temperature ( ∼ 60 K). The experimental results indicate that for the same (111) surface the adhesive force changes and oscillates with the island thickness. This phenomenon is shown to originate from the electron structure modulation by strong quantum size effects along the island surface normal direction, which modifies surface energy and leads to the observed oscillatory adhesive forces.
Applied Physics Letters 10/2006; 89(18):183109-183109-3. · 3.84 Impact Factor
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ABSTRACT: This paper summarizes our recent work on the study of quantum size effects (QSE) and novel physical properties of the Pb/Si
(111) heterostructure. Two different types of samples were investigated. One is wedge-shaped Pb islands, and the other is
atomically flat Pb thin films. With scanning tunneling microscopy (STM) manipulation, we observed an intriguing morphology
dynamics of the islands that swings between two extreme energy states, like that in a classical pendulum. We show that the
dynamics is a result of the competition between the QSE and the classical step free energy minimizing effect. For the second
type of the samples, the QSE is studied in terms of thickness-dependent film stability, electronic structure and physical
properties by using STM, angle-resolved photoemission spectroscopy (ARPES) and transport measurement. The results consistently
reveal the formation of quantum well states (QWS) due to electron confinement in the films. This size effect could greatly
modify the electronic structure near the Fermi level and lead to quantum oscillations in superconductivity, electron-phonon
coupling and thermal expansion. The work unambiguously demonstrates the possibility of quantum engineering of physical properties
of thin films by exploiting well-controlled and thickness-dependent QSE.
Frontiers of Physics in China 01/2006; 1(3):323-333. · 0.90 Impact Factor
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ABSTRACT: We report the thickness-dependent (in terms of atomic layers) oscillation behavior of the perpendicular upper critical field Hc2perpendicular in the ultrathin lead films at the reduced temperature (t = T/Tc). Distinct oscillations of the normal-state resistivity as a function of film thickness have also been observed. Compared with the Tc oscillation, the Hc2perpendicular shows a considerable large oscillation amplitude and a pi phase shift. The oscillatory mean free path caused by the quantum size effect plays a role in Hc2perpendicular oscillation.
Physical Review Letters 01/2006; 95(24):247005. · 7.37 Impact Factor
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ABSTRACT: Using a low temperature growth method, we have prepared atomically flat Pb thin films over a wide range of film thickness on a Si-(111)-7 x 7 surface. The Pb film morphology and electronic structure are investigated in situ by scanning tunneling microscopy and angle-resolved photoemission spectroscopy. Well-defined and atomic-layer-resolved quantum-well states of the Pb films are used to determine the band structure and the electron-phonon coupling constant (lambda) of the films. We found an oscillatory behavior of lambda with an oscillation periodicity of two atomic layers. Almost all essential features in the Pb/Si(111) system, such as the growth mode, the oscillatory film stability, and the 9 monolayer envelope beating pattern, can be explained by our results in terms of the electron confinement in Pb films.
Physical Review Letters 09/2005; 95(9):096802. · 7.37 Impact Factor
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Yang Guo, Yan-Feng Zhang,
Xin-Yu Bao,
Tie-Zhu Han,
Zhe Tang,
Li-Xin Zhang,
Wen-Guang Zhu,
E G Wang,
Qian Niu,
Z Q Qiu,
Jin-Feng Jia,
Zhong-Xian Zhao,
Qi-Kun Xue
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ABSTRACT: We have fabricated ultrathin lead films on silicon substrates with atomic-scale control of the thickness over a macroscopic area. We observed oscillatory behavior of the superconducting transition temperature when the film thickness was increased by one atomic layer at a time. This oscillating behavior was shown to be a manifestation of the Fabry-Perot interference modes of electron de Broglie waves (quantum well states) in the films, which modulate the electron density of states near the Fermi level and the electron-phonon coupling, which are the two factors that control superconductivity transitions. This result suggests the possibility of modifying superconductivity and other physical properties of a thin film by exploiting well-controlled and thickness-dependent quantum size effects.
Science 01/2005; 306(5703):1915-7. · 31.20 Impact Factor
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ABSTRACT: We propose the concept of a "Coulomb sink" to elucidate the effect of Coulomb charging on coarsening of metal mesas grown on semiconductor surfaces. We show that a charged mesa, due to its reduced chemical potential, acts as a Coulomb sink and grows at the expense of neighboring neutral mesas. The theory explains qualitatively the most salient features of coarsening of charged Pb mesas on the Si(111) surface, as observed by a scanning tunneling microscope. It provides a potentially useful method for controlled fabrication of metal nanostructures.
Physical Review Letters 10/2004; 93(10):106102. · 7.37 Impact Factor
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ABSTRACT: Quantum size effects are successfully exploited in manipulating the growth of (111) oriented Pb islands on Si(111) substrate with a scanning tunneling microscope. The growth dynamics and morphology displayed can be well controlled through the quantum size effects defined by the island thicknesses and the interplay with the classical forces. The transition of growth modes from quantum to classical regime and the quantum beating in morphological dynamics are directly identified in real space and quantitatively analyzed. Atomic diffusion barriers, an important parameter in the thin film growth process, are also demonstrated to be modified by quantum size effects, and oscillate with a two-monolayer periodicity.
Phys. Rev. B. 74(7).
