Hepatorenal syndrome(HRS) is defined as a functional renal failure in patients with liver disease with portal hypertension and it constitutes the climax of systemic circulatory changes associated with portal hypertens...Hepatorenal syndrome(HRS) is defined as a functional renal failure in patients with liver disease with portal hypertension and it constitutes the climax of systemic circulatory changes associated with portal hypertension.This term refers to a precisely specified syndrome featuring in particular morphologically intact kidneys,where regulatory mechanisms have minimised glomerular filtration and maximised tubular resorption and urine concentration,which ultimately results in uraemia.The syndrome occurs almost exclusively in patients with ascites.Type 1 HRS develops as a consequence of a severe reduction of effective circulating volume due to both an extreme splanchnic arterial vasodilatation and a reduction of cardiac output.Type 2 HRS is characterised by a stable or slowly progressive renal failure so that its main clinical consequence is not acute renal failure,but refractory ascites,and its impact on prognosis is less negative.Liver transplantation is the most appropriate therapeutic method,nevertheless,only a few patients can receive it.The most suitable "bridge treatments" or treatment for patients ineligible for a liver transplant include terlipressin plus albumin.Terlipressin is at an initial dose of 0.5-1 mg every 4 h by intravenous bolus to 3 mg every 4 h in cases when there is no response.Renal function recovery can be achieved in less than 50% of patients and a considerable decrease in renal function may reoccur even in patients who have been responding to therapy over the short term.Transjugular intrahepatic portosystemic shunt plays only a marginal role in the treatment of HRS.展开更多
Slow diffusion of diethylether into a concentrated solution of K2C454.H20 and two equivalents of 18-crown-6 in pyridine affords dark orange crystals of bis（potassium{18-crown-6}）（3-cyclobutene-1,2-dithione-3,4-dith...Slow diffusion of diethylether into a concentrated solution of K2C454.H20 and two equivalents of 18-crown-6 in pyridine affords dark orange crystals of bis（potassium{18-crown-6}）（3-cyclobutene-1,2-dithione-3,4-dithiolate） [K（C12H2406）]2（CnS4）. The crystal structure determination （monoclinic, P 2t/n, a = 12.2095（8） A, b = 11.3263（8） A, c = 14.0552（7） A, fl = 101.032（3）~, Z = 2） shows the presence of C4S42 - ions with almost undistorted D4h symmetry having C-C bond lengths of 1.442（10） A and 1.478（8） A and C-S bond lengths of 1.651（8） A and 1.664（7） A. Since the K＋ ions are shielded in a half-spherical way by the crown ether ligands, the crystal structures is built of centrosymmetric molecular entities [（18-crown-6）K（C4S4）K（18-crown-6）]. The K＋ ions have eight of coordination number, C4S42- acts as a chelating and bridging ligand towards two K＋ with K-S distances of 3.434（2） A and 3.380（2） A.展开更多
Refrigeration coefficient, ε, is usually calculated by using the First Law of Thermodynamics. In this paper, a new derivation process is introduced through the combination of the Second Law of Thermodynamics with the...Refrigeration coefficient, ε, is usually calculated by using the First Law of Thermodynamics. In this paper, a new derivation process is introduced through the combination of the Second Law of Thermodynamics with the First Law of Thermodynamics. As a result, two new calculation equations for refrigeration coefficient are proposed. One equation is equivalent to the common method, but its form is a little complicated for real calculation. Another equation is the further simplification, and can be used to calculate the refrigeration coefficient instead of common method with a oermit error.展开更多
Chemical reactions (such as hydrogenation, hydroformylation, alkylation, esterification, etc.) at supercritical conditions afford opportunities to manipulate the solubility of reactants and products, to eliminate inte...Chemical reactions (such as hydrogenation, hydroformylation, alkylation, esterification, etc.) at supercritical conditions afford opportunities to manipulate the solubility of reactants and products, to eliminate interphase transport limitations in the reaction systems, and to be beneficial to the environment. This review concentrates on the most recent developments after 2001 with only a brief summary of pioneering research work before 2001.展开更多
文摘Hepatorenal syndrome(HRS) is defined as a functional renal failure in patients with liver disease with portal hypertension and it constitutes the climax of systemic circulatory changes associated with portal hypertension.This term refers to a precisely specified syndrome featuring in particular morphologically intact kidneys,where regulatory mechanisms have minimised glomerular filtration and maximised tubular resorption and urine concentration,which ultimately results in uraemia.The syndrome occurs almost exclusively in patients with ascites.Type 1 HRS develops as a consequence of a severe reduction of effective circulating volume due to both an extreme splanchnic arterial vasodilatation and a reduction of cardiac output.Type 2 HRS is characterised by a stable or slowly progressive renal failure so that its main clinical consequence is not acute renal failure,but refractory ascites,and its impact on prognosis is less negative.Liver transplantation is the most appropriate therapeutic method,nevertheless,only a few patients can receive it.The most suitable "bridge treatments" or treatment for patients ineligible for a liver transplant include terlipressin plus albumin.Terlipressin is at an initial dose of 0.5-1 mg every 4 h by intravenous bolus to 3 mg every 4 h in cases when there is no response.Renal function recovery can be achieved in less than 50% of patients and a considerable decrease in renal function may reoccur even in patients who have been responding to therapy over the short term.Transjugular intrahepatic portosystemic shunt plays only a marginal role in the treatment of HRS.
文摘Slow diffusion of diethylether into a concentrated solution of K2C454.H20 and two equivalents of 18-crown-6 in pyridine affords dark orange crystals of bis（potassium{18-crown-6}）（3-cyclobutene-1,2-dithione-3,4-dithiolate） [K（C12H2406）]2（CnS4）. The crystal structure determination （monoclinic, P 2t/n, a = 12.2095（8） A, b = 11.3263（8） A, c = 14.0552（7） A, fl = 101.032（3）~, Z = 2） shows the presence of C4S42 - ions with almost undistorted D4h symmetry having C-C bond lengths of 1.442（10） A and 1.478（8） A and C-S bond lengths of 1.651（8） A and 1.664（7） A. Since the K＋ ions are shielded in a half-spherical way by the crown ether ligands, the crystal structures is built of centrosymmetric molecular entities [（18-crown-6）K（C4S4）K（18-crown-6）]. The K＋ ions have eight of coordination number, C4S42- acts as a chelating and bridging ligand towards two K＋ with K-S distances of 3.434（2） A and 3.380（2） A.
基金Supported by Shanghai Leading Academic Displine Project(No.B604)
文摘Refrigeration coefficient, ε, is usually calculated by using the First Law of Thermodynamics. In this paper, a new derivation process is introduced through the combination of the Second Law of Thermodynamics with the First Law of Thermodynamics. As a result, two new calculation equations for refrigeration coefficient are proposed. One equation is equivalent to the common method, but its form is a little complicated for real calculation. Another equation is the further simplification, and can be used to calculate the refrigeration coefficient instead of common method with a oermit error.
基金the National Key Fundamental Research Project (No. G2000048009) SINOPEC, China.
文摘Chemical reactions (such as hydrogenation, hydroformylation, alkylation, esterification, etc.) at supercritical conditions afford opportunities to manipulate the solubility of reactants and products, to eliminate interphase transport limitations in the reaction systems, and to be beneficial to the environment. This review concentrates on the most recent developments after 2001 with only a brief summary of pioneering research work before 2001.
