AIM： To identify clinical parameters, and develop an Upper Gastrointesinal Bleeding （UGIB） Etiology Score for predicting the types of UGIB and validate the score. METHODS： Patients with UGIB who underwent endoscop...AIM： To identify clinical parameters, and develop an Upper Gastrointesinal Bleeding （UGIB） Etiology Score for predicting the types of UGIB and validate the score. METHODS： Patients with UGIB who underwent endoscopy within 72 h were enrolled. Clinical and basic laboratory parameters were prospectively collected. Predictive factors for the types of UGIB were identified by univariate and multivariate analyses and were used to generate the UGIB Etiology Score. The best cutoff of the score was defined from the receiver operating curve and prospectively validated in another set of patients with UGIB. RESULTS： Among 261 patients with UGIB, 47 （18%） had variceal and 214 （82%） had non-variceal bleeding. Univariate analysis identified 27 distinct parameters significantly associated with the types of UGIB. Logistic regression analysis identified only 3 independent factors for predicting variceal bleeding; previous diagnosis of cirrhosis or signs of chronic liver disease （OR 22.4, 95% CI 8.3-60.4, P 〈 0.001）, red vomitus （OR 4.6, 95% CI 1.8-11.9, P = 0.02）, and red nasogastric （NG） aspirate （OR 3.3, 95% CI 1.3-8.3, P = 0.011）. The UGIB Etiology Score was calculated from （3.1× previous diagnosis of cirrhosis or signs of chronic liver disease） ＋ （1.5× red vomitus） ＋ （1.2× red NG aspirate）, when 1 and 0 are used for the presence and absence of each factor, respectively. Using a cutoff ≥ 3.1, the sensitivity, specificity, accuracy, positive predictive value （PPV）, and negative predictive value （NPV） in predicting variceal bleeding were 85%, 81%, 82%, 50%, and 96%, respectively. The score was prospectively validated in cases （46 variceal and 149 another set of 195 UGIB non-variceal bleeding）. The PPV and NPV of a score ≥ 3.1 for variceal bleeding were 79% and 97%, respectively. CONCLUSION： The UGIB Etiology Score, composed of 3 parameters, using a cutoff ≥ 3.1 accurately predicted variceal bleeding and may help to guide the choice of initial therapy for UGIB before endoscopy.展开更多
Objectives To assess the regional diastolic function in patients with hypertrophic cardiomyopathy （HCM） by using single-beat, real-time, three-dimensional echocardiography （RT-3DE）. Methods Sixty-five patients wit...Objectives To assess the regional diastolic function in patients with hypertrophic cardiomyopathy （HCM） by using single-beat, real-time, three-dimensional echocardiography （RT-3DE）. Methods Sixty-five patients with HCM in sinus rhythm together with fifty age- and gender-matched normal controls were studied by two dimensional echocardiography （2DE） and RT-3DE. The parameters analyzed by RT-3DE included： left ventrieular （LV） volumes, left ventricular ejection fraction （LVEF）, end diastolic sphericity index （EDSI）, diastolic dyssynchrony index （DDI）, dispersion end diastole （DISPED）, and normalized 17 segmental volume-time curves. Results Evaluated by RT-3DE, LVEF was slightly lower compared with 2DE （63.2 ± 6.8% vs. 59.1 ± 6.4%, P 〈 0.0001）. Normal subjects had relatively uniform volumetric curves for all LV segments. In HCM patients, the segmental volumetric curves were dyssynchronous. Increased DDI and DISPED in end diastole were observed in patients with HCM （9.95 ± 3.75, 41.76 ± 17.19, P 〈 0.0001）, and not all abnormal volumetric segments occurred in the hypertrophic regions. Conclusions Patients with HCM have presented regional diastolic dyssynchrony in the diastole phase, and this preclinical lesion can be recognized by single-beat RT-3DE.展开更多
Numerous experimental studies reveal that the mechanical and deformational behaviors of sands are dependent on the combined effect of void ratio and stress. To predict this complex behavior of sands, a hypo-elastic mo...Numerous experimental studies reveal that the mechanical and deformational behaviors of sands are dependent on the combined effect of void ratio and stress. To predict this complex behavior of sands, a hypo-elastic model is developed based on the cross-anisotropic elasticity model, which involves four parameters: bulk module, tangent Young's module, volume deformation coefficient and Poisson ratio. A parameter defined as virtual peak deviatoric stress dependent on state parameter is introduced into hyperbolic stress strain relationship to determine tangent Young's module. In addition, an existing fitting equation for isotropic compression curves and an existing dilatancy equation, which can consider the effect of state of sands, are employed to determine bulk module and volume deformation coefficient. Thirteen model constants are involved in the proposed model, the values of which are fixed for a sand over a wide range of initial void ratios and initial confining pressures. Well known experimental data for drained and undrained triaxial compression tests of Toyoura sand are successfully modeled.展开更多
The theoretical light curves of contact binaries are calculated with and without putting in the contact binary evolution model.Firstly,we do not use the contact binary evolution model.A comparison of the light curve i...The theoretical light curves of contact binaries are calculated with and without putting in the contact binary evolution model.Firstly,we do not use the contact binary evolution model.A comparison of the light curve is performed with and without the deformation caused by rotation and tides.It shows that the light curve presents many differences,especially on the bottom and top.Secondly,we adopt the contact binary model [Huang R Q,et al.Chin J Astron Astrophys,2007,7:235-244;Song H F,et al.Chin J Astron Astrophys,2007,7:539-550] and compute the theoretical light curve with and without rotational and tidal effects by studying three binary systems(with low-,intermediate-and high-mass components).The bottom and top of the theoretical light curves are discussed and compared to observations.The results show that taking into account the rotational effect has a better agreement with observations than without it.Therefore,the deformation of the light curve of contact binaries caused by rotation and tides is very important.Meanwhile,the rotational and tidal effect can advance the start of the semi-detached,contact phase and the time of mass-reversal.展开更多
文摘AIM： To identify clinical parameters, and develop an Upper Gastrointesinal Bleeding （UGIB） Etiology Score for predicting the types of UGIB and validate the score. METHODS： Patients with UGIB who underwent endoscopy within 72 h were enrolled. Clinical and basic laboratory parameters were prospectively collected. Predictive factors for the types of UGIB were identified by univariate and multivariate analyses and were used to generate the UGIB Etiology Score. The best cutoff of the score was defined from the receiver operating curve and prospectively validated in another set of patients with UGIB. RESULTS： Among 261 patients with UGIB, 47 （18%） had variceal and 214 （82%） had non-variceal bleeding. Univariate analysis identified 27 distinct parameters significantly associated with the types of UGIB. Logistic regression analysis identified only 3 independent factors for predicting variceal bleeding; previous diagnosis of cirrhosis or signs of chronic liver disease （OR 22.4, 95% CI 8.3-60.4, P 〈 0.001）, red vomitus （OR 4.6, 95% CI 1.8-11.9, P = 0.02）, and red nasogastric （NG） aspirate （OR 3.3, 95% CI 1.3-8.3, P = 0.011）. The UGIB Etiology Score was calculated from （3.1× previous diagnosis of cirrhosis or signs of chronic liver disease） ＋ （1.5× red vomitus） ＋ （1.2× red NG aspirate）, when 1 and 0 are used for the presence and absence of each factor, respectively. Using a cutoff ≥ 3.1, the sensitivity, specificity, accuracy, positive predictive value （PPV）, and negative predictive value （NPV） in predicting variceal bleeding were 85%, 81%, 82%, 50%, and 96%, respectively. The score was prospectively validated in cases （46 variceal and 149 another set of 195 UGIB non-variceal bleeding）. The PPV and NPV of a score ≥ 3.1 for variceal bleeding were 79% and 97%, respectively. CONCLUSION： The UGIB Etiology Score, composed of 3 parameters, using a cutoff ≥ 3.1 accurately predicted variceal bleeding and may help to guide the choice of initial therapy for UGIB before endoscopy.
文摘Objectives To assess the regional diastolic function in patients with hypertrophic cardiomyopathy （HCM） by using single-beat, real-time, three-dimensional echocardiography （RT-3DE）. Methods Sixty-five patients with HCM in sinus rhythm together with fifty age- and gender-matched normal controls were studied by two dimensional echocardiography （2DE） and RT-3DE. The parameters analyzed by RT-3DE included： left ventrieular （LV） volumes, left ventricular ejection fraction （LVEF）, end diastolic sphericity index （EDSI）, diastolic dyssynchrony index （DDI）, dispersion end diastole （DISPED）, and normalized 17 segmental volume-time curves. Results Evaluated by RT-3DE, LVEF was slightly lower compared with 2DE （63.2 ± 6.8% vs. 59.1 ± 6.4%, P 〈 0.0001）. Normal subjects had relatively uniform volumetric curves for all LV segments. In HCM patients, the segmental volumetric curves were dyssynchronous. Increased DDI and DISPED in end diastole were observed in patients with HCM （9.95 ± 3.75, 41.76 ± 17.19, P 〈 0.0001）, and not all abnormal volumetric segments occurred in the hypertrophic regions. Conclusions Patients with HCM have presented regional diastolic dyssynchrony in the diastole phase, and this preclinical lesion can be recognized by single-beat RT-3DE.
基金Project(2010BC732101)supported by the National Basic Research Program of China
文摘Numerous experimental studies reveal that the mechanical and deformational behaviors of sands are dependent on the combined effect of void ratio and stress. To predict this complex behavior of sands, a hypo-elastic model is developed based on the cross-anisotropic elasticity model, which involves four parameters: bulk module, tangent Young's module, volume deformation coefficient and Poisson ratio. A parameter defined as virtual peak deviatoric stress dependent on state parameter is introduced into hyperbolic stress strain relationship to determine tangent Young's module. In addition, an existing fitting equation for isotropic compression curves and an existing dilatancy equation, which can consider the effect of state of sands, are employed to determine bulk module and volume deformation coefficient. Thirteen model constants are involved in the proposed model, the values of which are fixed for a sand over a wide range of initial void ratios and initial confining pressures. Well known experimental data for drained and undrained triaxial compression tests of Toyoura sand are successfully modeled.
基金supported by the National Natural Science Foundation of China (Grant No.10933002)
文摘The theoretical light curves of contact binaries are calculated with and without putting in the contact binary evolution model.Firstly,we do not use the contact binary evolution model.A comparison of the light curve is performed with and without the deformation caused by rotation and tides.It shows that the light curve presents many differences,especially on the bottom and top.Secondly,we adopt the contact binary model [Huang R Q,et al.Chin J Astron Astrophys,2007,7:235-244;Song H F,et al.Chin J Astron Astrophys,2007,7:539-550] and compute the theoretical light curve with and without rotational and tidal effects by studying three binary systems(with low-,intermediate-and high-mass components).The bottom and top of the theoretical light curves are discussed and compared to observations.The results show that taking into account the rotational effect has a better agreement with observations than without it.Therefore,the deformation of the light curve of contact binaries caused by rotation and tides is very important.Meanwhile,the rotational and tidal effect can advance the start of the semi-detached,contact phase and the time of mass-reversal.
