On basis of bond dissociation energies (BDEs) for BH2, B(OH)2, BCl2, and BCl, the diffusion Monte Carlo (DMC) method is applied to explore the BDEs of HB-H, HOB-OH, ClB-Cl, and B-Cl. The effect of the choice of ...On basis of bond dissociation energies (BDEs) for BH2, B(OH)2, BCl2, and BCl, the diffusion Monte Carlo (DMC) method is applied to explore the BDEs of HB-H, HOB-OH, ClB-Cl, and B-Cl. The effect of the choice of orbitals, as well as the backflow transformation, is studied. The Slater-Jastrow DMC algorithm gives BDEs of 359.1±0.12 kJ/mol for HB-H, 410.5±0.50 kJ/mol for HOB-OH, 357.8±1.46 kJ/mol for ClB-Cl, and 504.5±0.96 kJ/mol for B-Cl using B3PW91 orbitals and similar BDEs when B3LYP orbitals are used. DMC with backflow corrections (BF-DMC) gives a HB-H BDE of 369.9±0.12 kJ/mol which is close to one of the available experimental value (375.8 kJ/mol). In the case of HOB-OH BDE, the BF-DMC calculation is 446.04-1.84 k J/mol that is closer to the experimental BDE. The BF-DMC BDE for ClB-Cl is 343.2±2.34 kJ/mol and the BF-DMC B-Cl BDE is 523.3±0.33 kJ/mol, which are close to the experimental BDEs, 341.9 and 530.0 kJ/mol, respectively.展开更多
AIM:To determine the role of CD133 in cholangiocarcinoma progression. METHODS:CD133 protein expression was evaluated by immunohistochemistry in 34 cholangiocarcinoma specimens.In addition,proliferation,chemoresistance...AIM:To determine the role of CD133 in cholangiocarcinoma progression. METHODS:CD133 protein expression was evaluated by immunohistochemistry in 34 cholangiocarcinoma specimens.In addition,proliferation,chemoresistance and invasive properties of CD133-enriched(CD133 + ) and CD133-depleted(CD133 )RMCCA1 cholangiocarcinoma cells were studied and compared. RESULTS:Strong CD133 expression was observed in 67.6%(23/34)of the cholangiocarcinoma specimens. Strong expression of CD133 was significantly associated with nodal metastasis(P=0.009)and positive surgical margin status(P=0.011).In the in vitro study, both the CD133 + and CD133 cells had similar proliferation abilities and resistance to chemotherapeutic drugs.However,the CD133 + cells had a higher invasive ability compared with CD133 cells. CONCLUSION:CD133+cells play an important role in the invasiveness of cholangiocarcinoma.Targeting of the CD133+cells may be a useful approach to improve treatment against cholangiocarcinoma.展开更多
Diffusion-weighted magnetic resonance imaging(DWI)is a well established method for the evaluation of intracranial diseases,such as acute stroke.DWI for extracranial application is more difficult due to physiological m...Diffusion-weighted magnetic resonance imaging(DWI)is a well established method for the evaluation of intracranial diseases,such as acute stroke.DWI for extracranial application is more difficult due to physiological motion artifacts and the heterogeneous composition of the organs.However,thanks to the newer technical development of DWI,DWI has become increasingly used over the past few years in extracranial organs including the abdomen and pelvis.Most previous studies of DWI have been limited to the evaluation of diffuse parenchymal abnormalities and focal lesions in abdominal organs,whereas there are few studies about DWI for the evaluation of the biliopancreatic tract.Although further studies are needed to determine its performance in evaluating bile duct,gallbladder and pancreas diseases,DWI has potential in the assessment of the functional information on the biliopancreatic tract concerning the status of tissue cellularity,because increased cellularity is associated with impeded diffusion,as indicated by a reduction in the apparent diffusion coefficient.The detection of malignant lesions and their differentiation from benign tumor-like lesions in the biliopancreatic tract could be improved using DWI in conjunction with findings obtained with conventional magnetic resonance cholagiopancreatography.Additionally,DWI can be useful for the assessment of the biliopancreatic tract in patients with renal impairment because contrast-enhanced computed tomography or magnetic resonance scans should be avoided in these patients.展开更多
Expanded bed adsorption(EBA),a promising and practical separation technique,has been widely studied in the past two decades.The development of adsorbents for EBA process is a challenging course,with the special design...Expanded bed adsorption(EBA),a promising and practical separation technique,has been widely studied in the past two decades.The development of adsorbents for EBA process is a challenging course,with the special design and preparation according to the target molecules and specific expanded bed systems.Many types of supporting matrices for expanded bed adsorbents have been developed,and their preparation methods are being consummated gradually.These matrices are activated and then coupled with ligands to form functionalized adsorbents,including ion-exchange adsorbents,affinity adsorbents,mixed mode adsorbents,hydrophobic charge induction chromatography adsorbents and others.In this review,the preparation of the matrices for EBA process is summa-rized,and the coupling of ligands to the matrices to prepare functionalized adsorbents is discussed as well.展开更多
The interaction between a solute atom and an extended dislocation was investigated using a continuum approximation method with force multipoles.The dislocation core structure of extended dislocation was modeled with t...The interaction between a solute atom and an extended dislocation was investigated using a continuum approximation method with force multipoles.The dislocation core structure of extended dislocation was modeled with the Peierls-Nabarro model discretized with a number of infinitesimal Volterra dislocations.The interaction energy and force between a nickel solute atom and perfect and extended dislocation in copper were successfully calculated using the force multipoles.The results clearly show that the core structure of extended dislocation weakens the interaction with solute atoms.The interaction energy and force for extended dislocations are almost the half of those for perfect dislocations.展开更多
Asymptotic energy expansion method is extended for polynomial potentials having rational powers. New types of recurrence relations are derived for the potentials of the form rig, mN are positive integers while coeffic...Asymptotic energy expansion method is extended for polynomial potentials having rational powers. New types of recurrence relations are derived for the potentials of the form rig, mN are positive integers while coefficients bk ∈ C. As in the case of even degree polynomial potentials with integer powers, all the integrals in the expansion can be evaluated analytically in terms of F functions. With the help of two examples, we demonstrate the usefulness of these expansions in getting analytic insight into the quantum systems having rational power polynomial potentials.展开更多
文摘On basis of bond dissociation energies (BDEs) for BH2, B(OH)2, BCl2, and BCl, the diffusion Monte Carlo (DMC) method is applied to explore the BDEs of HB-H, HOB-OH, ClB-Cl, and B-Cl. The effect of the choice of orbitals, as well as the backflow transformation, is studied. The Slater-Jastrow DMC algorithm gives BDEs of 359.1±0.12 kJ/mol for HB-H, 410.5±0.50 kJ/mol for HOB-OH, 357.8±1.46 kJ/mol for ClB-Cl, and 504.5±0.96 kJ/mol for B-Cl using B3PW91 orbitals and similar BDEs when B3LYP orbitals are used. DMC with backflow corrections (BF-DMC) gives a HB-H BDE of 369.9±0.12 kJ/mol which is close to one of the available experimental value (375.8 kJ/mol). In the case of HOB-OH BDE, the BF-DMC calculation is 446.04-1.84 k J/mol that is closer to the experimental BDE. The BF-DMC BDE for ClB-Cl is 343.2±2.34 kJ/mol and the BF-DMC B-Cl BDE is 523.3±0.33 kJ/mol, which are close to the experimental BDEs, 341.9 and 530.0 kJ/mol, respectively.
基金Supported by Rajavithi Hospital Project Grant and Thailand Research Fund(RSA52)
文摘AIM:To determine the role of CD133 in cholangiocarcinoma progression. METHODS:CD133 protein expression was evaluated by immunohistochemistry in 34 cholangiocarcinoma specimens.In addition,proliferation,chemoresistance and invasive properties of CD133-enriched(CD133 + ) and CD133-depleted(CD133 )RMCCA1 cholangiocarcinoma cells were studied and compared. RESULTS:Strong CD133 expression was observed in 67.6%(23/34)of the cholangiocarcinoma specimens. Strong expression of CD133 was significantly associated with nodal metastasis(P=0.009)and positive surgical margin status(P=0.011).In the in vitro study, both the CD133 + and CD133 cells had similar proliferation abilities and resistance to chemotherapeutic drugs.However,the CD133 + cells had a higher invasive ability compared with CD133 cells. CONCLUSION:CD133+cells play an important role in the invasiveness of cholangiocarcinoma.Targeting of the CD133+cells may be a useful approach to improve treatment against cholangiocarcinoma.
基金Supported by Clinical research grant from Pusan National University Hospital
文摘Diffusion-weighted magnetic resonance imaging(DWI)is a well established method for the evaluation of intracranial diseases,such as acute stroke.DWI for extracranial application is more difficult due to physiological motion artifacts and the heterogeneous composition of the organs.However,thanks to the newer technical development of DWI,DWI has become increasingly used over the past few years in extracranial organs including the abdomen and pelvis.Most previous studies of DWI have been limited to the evaluation of diffuse parenchymal abnormalities and focal lesions in abdominal organs,whereas there are few studies about DWI for the evaluation of the biliopancreatic tract.Although further studies are needed to determine its performance in evaluating bile duct,gallbladder and pancreas diseases,DWI has potential in the assessment of the functional information on the biliopancreatic tract concerning the status of tissue cellularity,because increased cellularity is associated with impeded diffusion,as indicated by a reduction in the apparent diffusion coefficient.The detection of malignant lesions and their differentiation from benign tumor-like lesions in the biliopancreatic tract could be improved using DWI in conjunction with findings obtained with conventional magnetic resonance cholagiopancreatography.Additionally,DWI can be useful for the assessment of the biliopancreatic tract in patients with renal impairment because contrast-enhanced computed tomography or magnetic resonance scans should be avoided in these patients.
基金Supported by the National Natural Science Foundation of China (20876139, 20776129) and the National Basic Research Program of China (2007CB707805).
文摘Expanded bed adsorption(EBA),a promising and practical separation technique,has been widely studied in the past two decades.The development of adsorbents for EBA process is a challenging course,with the special design and preparation according to the target molecules and specific expanded bed systems.Many types of supporting matrices for expanded bed adsorbents have been developed,and their preparation methods are being consummated gradually.These matrices are activated and then coupled with ligands to form functionalized adsorbents,including ion-exchange adsorbents,affinity adsorbents,mixed mode adsorbents,hydrophobic charge induction chromatography adsorbents and others.In this review,the preparation of the matrices for EBA process is summa-rized,and the coupling of ligands to the matrices to prepare functionalized adsorbents is discussed as well.
文摘The interaction between a solute atom and an extended dislocation was investigated using a continuum approximation method with force multipoles.The dislocation core structure of extended dislocation was modeled with the Peierls-Nabarro model discretized with a number of infinitesimal Volterra dislocations.The interaction energy and force between a nickel solute atom and perfect and extended dislocation in copper were successfully calculated using the force multipoles.The results clearly show that the core structure of extended dislocation weakens the interaction with solute atoms.The interaction energy and force for extended dislocations are almost the half of those for perfect dislocations.
文摘Asymptotic energy expansion method is extended for polynomial potentials having rational powers. New types of recurrence relations are derived for the potentials of the form rig, mN are positive integers while coefficients bk ∈ C. As in the case of even degree polynomial potentials with integer powers, all the integrals in the expansion can be evaluated analytically in terms of F functions. With the help of two examples, we demonstrate the usefulness of these expansions in getting analytic insight into the quantum systems having rational power polynomial potentials.