BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require furt...BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require further clinical evaluation and investigation.AIM To explore the application value of the"five steps four quadrants"modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients.METHODS A total of 52 patients who underwent LPD via the"five steps four quadrants"modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively.The patients'body mass index(BMI),preoperative laboratory indices,intraoperative variables and postoperative complications were recorded.The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed.RESULTS Among the 52 patients,36 were males and 16 were females,and the average age was 62.2±11.0 years.There were 26 patients with pancreatic head cancer,16 patients with periampullary cancer,and 10 patients with distal bile duct cancer.The BMI was 22.3±3.3 kg/m²,and the median total bilirubin(TBIL)concentration was 57.7(16.0-155.7)µmol/L.All patients successfully underwent the"five steps four quadrants"modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage.Correlation analysis revealed significant associations between preoperative BMI(r=0.3581,P=0.0091),TBIL level(r=0.2988,P=0.0341),prothrombin time(r=0.3018,P=0.0297)and lymph node dissection time.Moreover,dissection time was significantly correlated with intraoperative blood loss(r=0.7744,P<0.0001).Further stratified analysis demonstrated that patients with a preoperative BMI≥21.9 kg/m²and a TIBL concentration≥57.7μmol/L had significantly longer lymph node dissection times(both P<0.05).CONCLUSION The"five steps four quadrants"modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD.This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve;thus,it is worthy of further clinical promotion and application.展开更多
In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements ha...In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements have been applied for establishing, the stoichiometry and whenever possible, the stability constants of the chelates formed. The method of continuous variations was necessary to determine first whether, the metal ion and the ligand ethylene diamine form one or more than one chelate, when more than one chelate formed, the results obtained depend on the wavelength and for meaningful conclusions the wavelengths were carefully selected. The empirical formulae of the chelates were further substantiated by the molar ratio method. The effect of time and temperature on the formation and stability of these chelates in solution is also studied. The stability constants, K1 and K2 for the copper (II) chelates were calculated, though reliable, and are comparable to literature values.展开更多
The Global Energy Interconnection is an important strategic approach used to achieve efficient worldwide energy allocation.The idea of developing integrated power,information,and transportation networks provides incre...The Global Energy Interconnection is an important strategic approach used to achieve efficient worldwide energy allocation.The idea of developing integrated power,information,and transportation networks provides increased power interconnection functionality and meaning,helps condense forces,and accelerates the integration of global infrastructure.Correspondingly,it is envisaged that it will become the trend of industrial technological development in the future.In consideration of the current trend of integrated development,this study evaluates a possible plan of coordinated development of fiber-optic and power networks in the Pan-Arctic region.Firstly,the backbone network architecture of Global Energy Interconnection is introduced and the importance of the Arctic energy backbone network is confirmed.The energy consumption and developmental trend of global data centers are then analyzed.Subsequently,the global network traffic is predicted and analyzed by means of a polynomial regression model.Finally,in combination with the current construction of fiber-optic networks in the Pan-Arctic region,the advantages of the integration of the fiber-optic and power networks in this region are clarified in justification of the decision for the development of a Global Energy Interconnection scheme.展开更多
Ene-chtorination of the otefins bearing isopropenyl moieties has been achieved in good yieid by using catcium hypochiorite and sodium biphosphate. An efficient synthesis of San Jose ScaLe's sex pheromone is descri...Ene-chtorination of the otefins bearing isopropenyl moieties has been achieved in good yieid by using catcium hypochiorite and sodium biphosphate. An efficient synthesis of San Jose ScaLe's sex pheromone is described.展开更多
To analyze the effects of width and thickness of each composition element of mixed steel U-rib-stiffened plates on the welding residual stress distribution, the distribution of the U-rib and the plate residual stress ...To analyze the effects of width and thickness of each composition element of mixed steel U-rib-stiffened plates on the welding residual stress distribution, the distribution of the U-rib and the plate residual stress was calculated using a simplified calculation method. The method involved welding the mixed steel U-rib-stiffened plates for a structure with different sizes and different strength ratios of U-rib to plate. Based on a welding residual stress numerical simulation method validated by the blind hole method test, the distribution law of the mixed steel U-rib stiffened plate was studied. The results showed that the change of plate width has little impact on the welding residual stress and that the ratio of the thicknesses of the plate to U-rib stiffeners, the thickness of the plate, and the thickness of the U-rib has a great influence on the distribution of the welding residual stress. The thickness of plate and steel strength also greatly influenced the distribution width of the residual tensile stress. While analyzing the compression capacity of U-rib-stiffened plates, the simplified distribution of welding residual stress was used.展开更多
We investigate the absorption properties of cyclotrimethylene trinitramine(RDX) single crystals from ~15 to150 cm^(-1) using the terahertz time-domain spectroscopy. We observe that all the absorption modes exhibit str...We investigate the absorption properties of cyclotrimethylene trinitramine(RDX) single crystals from ~15 to150 cm^(-1) using the terahertz time-domain spectroscopy. We observe that all the absorption modes exhibit strong anisotropic behavior in terms of the crystal orientations. We demonstrate that the anharmonic phonon model can well describe the temperature-dependent behaviors of these absorption modes. These results indicate that the intermolecular interaction plays a major role in the collective motion of large number of RDX molecules. Our findings provide important information for understanding and controlling the dynamic properties in the explosive materials.展开更多
The catalytic performance of a series of cobalt(Ⅱ) hydroxamates (CoL2) and the synergistic catalytic action of the cobalt complexes combined with N-hydroxyphthalimide (NHPI) in the aerobic oxidation of p-xylene to p-...The catalytic performance of a series of cobalt(Ⅱ) hydroxamates (CoL2) and the synergistic catalytic action of the cobalt complexes combined with N-hydroxyphthalimide (NHPI) in the aerobic oxidation of p-xylene to p-toluic acid (PTA) were investigated. The results showed that the existing synergistic action in the catalytic oxidation can shorten the induction period of the radical reaction and improve the yield of PTA.展开更多
BACKGROUND Single loop reconstruction(SLR) was routine in our institution for patients undergoing pancreatico-duodenectomy(PD). Roux-en Y reconstruction with an isolated gastric limb(RIGL) recently became the reconstr...BACKGROUND Single loop reconstruction(SLR) was routine in our institution for patients undergoing pancreatico-duodenectomy(PD). Roux-en Y reconstruction with an isolated gastric limb(RIGL) recently became the reconstruction of choice.AIM To evaluate the impact of RIGL on incidence and severity of delayed gastric emptying(DGE).METHODS This is a single institution, retrospective analysis of patients undergoing PD. All patients undergoing PD from July 2010 through December 2016 were included in the study. Outcome of RIGL were compared to SLR. Primary measure of outcome included incidence and severity of DGE. Secondary measures of outcome were overall complications and postoperative mortality.RESULTS One hundred and seventy-nine patients were included in the study. Fifty-two had RIGL, 127 had SLR. Overall complication rate was 40.2%, patients in the RIGL group experienced lower rates of DGE(15.4% vs 59.1%, P = 0.001). Other patient related outcomes were also significantly reduced: day of nasogastric tube removal(3 vs 5, P < 0.001), regain of normal diet(8 vs 9, P < 0.001). On multivariate analysis RIGL was associated independently with reduced rates of DGE(P < 0.001, OR 0.14)CONCLUSION The current study shows that RIGL reduces the rate of DGE after PD. Further prospective randomized controlled trials are required to affirm the current data.展开更多
In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores....In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores.The thermodynamic model was constructed and the solubility of malachite Cu2(OH)2CO3 in the ammonia-ammonium chloride-ethylenediamine(En)-water system was calculated using the exponential computation method based on both mass balance and charge balance.It is found that the solubility of copper can be increased and the free ammonia concentration can be decreased by submitting partial ammonia with ethylenediamine.The lower free ammonia concentration in the solution is a guarantee to the lower evaporating rate of ammonia.The conditions of malachite Cu2(OH)2CO3 converting to atacamite Cu(OH)1.5Cl0.5 were also studied.A group of experiments were designed to validate the veracity of the results of the thermodynamic calculation.It is found that the thermodynamic model is reliable and it can guide the leaching process.展开更多
observations from the field and the taboratory show that en echelon fractures withinfracture zones have a foede1 within Ricdel structure’ The tensile fallure mecbanism of en echelonfractures can be described by the p...observations from the field and the taboratory show that en echelon fractures withinfracture zones have a foede1 within Ricdel structure’ The tensile fallure mecbanism of en echelonfractures can be described by the pile-ups of sbear crack-dislocations. A fractal model can be used tosimulate the Riedel within Xiedel geometry, allowing the direct rneasarement of tbe ftactal dimen sions of en echelon fractare systems. The energy dissipation of tbe en ccbe1on fracture system canbe deduced using a fracil damage evo1ution model which exptalns tbe evo1ution process of en eche lon fracture svstems. The fractal nature of the fractures can be used to dcrive an accurate estimateof total energy dissipation.展开更多
New Schiff base Macrocyclic compound of 2,3: 11, 12:20, 21:29, 30-tetrabenzo-1,13,16,19,31,34-hexaoxa-5,6,8,9,23,24,26,27-octaaza-7,25-dithione-2,3:4,5:9,10:11,12:22, 23:27,28:29,30 cyclo-[36]ene (thione2B4[36] ene-O6...New Schiff base Macrocyclic compound of 2,3: 11, 12:20, 21:29, 30-tetrabenzo-1,13,16,19,31,34-hexaoxa-5,6,8,9,23,24,26,27-octaaza-7,25-dithione-2,3:4,5:9,10:11,12:22, 23:27,28:29,30 cyclo-[36]ene (thione2B4[36] ene-O6N8) containing THF has been prepared. It crystallizes in the monoclinic, space group P21/n. with parameters a=9.829(5) b=24.23(1), c=10.181(9), β=92.93(5)°, Z=2, V=2422(3)3, Dc=1.25gcm-3. Data collection: Rigaku AFC-5R diffractometer,(MoKα, λ=0.71069), ω /2θ scans. θmax=25°, empirical absorption correction, 4658 measured reflections, 4387 independent, 1743 observed reflections [I≥3σ(I)]. The final R=0.056. RW=0.069,S=1 .54, (Δ/σ)max=0.01,Δρmax=0.36e-3.展开更多
The reaction of (-)-menthyl gloxylate 2 with homoallyl silyl ether 3 under I ewis acid conditions gave optically active one-reaction product 4 with de in a range of 20-45°and 4-chloro-2-hydroxy carboxylate 5 The ...The reaction of (-)-menthyl gloxylate 2 with homoallyl silyl ether 3 under I ewis acid conditions gave optically active one-reaction product 4 with de in a range of 20-45°and 4-chloro-2-hydroxy carboxylate 5 The effect of suloxy group and Lewis acid on the regio- and stereochemistry and distribution of 4 and 5 in the mixture of the product product was examined.展开更多
field attraction test of (7R,8S)-cis-7,8-epoxy-2- methyloctadec-17-ene (= 7R,8S-epo-2me-17ene-18Hy), a trace component of the sex pheromone gland of the Asian gypsy moth,(Lymantria dispar), traps that were baited with...field attraction test of (7R,8S)-cis-7,8-epoxy-2- methyloctadec-17-ene (= 7R,8S-epo-2me-17ene-18Hy), a trace component of the sex pheromone gland of the Asian gypsy moth,(Lymantria dispar), traps that were baited with the trace component attracted more L. dispar than traps baited with (7S,8R)-cis-7,8-epoxy-2-methyloctadec-17-ene (= 7S,8R-epo-2me-17ene-18Hy) and unbaited traps. However, traps baited with 7R,8S-epo-2me-17ene-18Hy were less attractive than traps baited with (+)-disparlure [=(7R,8S)-cis-7,8-epoxy-2-methyloctadecane], the sex pheromone of L. dispar. Combination tests with (?)-disparlure, 7R,8S-epo-2me-17ene-18Hy, and 7S,8R-epo-2me- 17ene-18Hy revealed that 7R,8S-epo-2me-17ene-18Hy acted synergistically with (?)-disparlure.展开更多
Growth hormone (GH) is a polypeptide hormone secreted by the pituitary, which promotes animal growth, muscle development, metabolism regulation and other important physiological functions. In this study, a pair of m...Growth hormone (GH) is a polypeptide hormone secreted by the pituitary, which promotes animal growth, muscle development, metabolism regulation and other important physiological functions. In this study, a pair of mGH short hairpin RNA (shRNA) was designed according to mouse ( Mus musculus) GH mRNA sequence; pSingle-tTS-mGH shRNA-RFP, an integrated controllable expression vector of mGH shRNA, was constructed successfully. The recombinant vector was transfected into mouse pituitary tumor cell line AtT-20. After addition of doxycyelin ( DOX), the expression of red fluorescent protein (RFP) was observed un- der a fluorescent microscope. The expression level of mGH in cells was detected by quantitative Realtime PCR (qRT-PCR) and Western blot. After DOX induction, the relative expression level of GH mRNA in cells transfected with GH shRNA was reduced by about 70% compared with that in DOX-free group and other control groups, exhibiting extremely significant differences (P 〈 0.01 ) ; moreover, the relative expression level of GH protein was reduced by about 90% ; the expression level of GH mRNA and GH protein exhibited no significant difference among other groups (P 〉 0.05). In this study, a controllable expression vector of GH shRNA with high gene silencing efficiency was constructed successfully, which could be used to reveal GH autocfine / paracrine interactions and analyze functions of GH gene in growth, development and disease occurrence of animals by regulating GH expression levels.展开更多
基金Supported by Health Research Program of Anhui,No.AHWJ2022b032。
文摘BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require further clinical evaluation and investigation.AIM To explore the application value of the"five steps four quadrants"modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients.METHODS A total of 52 patients who underwent LPD via the"five steps four quadrants"modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively.The patients'body mass index(BMI),preoperative laboratory indices,intraoperative variables and postoperative complications were recorded.The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed.RESULTS Among the 52 patients,36 were males and 16 were females,and the average age was 62.2±11.0 years.There were 26 patients with pancreatic head cancer,16 patients with periampullary cancer,and 10 patients with distal bile duct cancer.The BMI was 22.3±3.3 kg/m²,and the median total bilirubin(TBIL)concentration was 57.7(16.0-155.7)µmol/L.All patients successfully underwent the"five steps four quadrants"modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage.Correlation analysis revealed significant associations between preoperative BMI(r=0.3581,P=0.0091),TBIL level(r=0.2988,P=0.0341),prothrombin time(r=0.3018,P=0.0297)and lymph node dissection time.Moreover,dissection time was significantly correlated with intraoperative blood loss(r=0.7744,P<0.0001).Further stratified analysis demonstrated that patients with a preoperative BMI≥21.9 kg/m²and a TIBL concentration≥57.7μmol/L had significantly longer lymph node dissection times(both P<0.05).CONCLUSION The"five steps four quadrants"modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD.This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve;thus,it is worthy of further clinical promotion and application.
文摘In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements have been applied for establishing, the stoichiometry and whenever possible, the stability constants of the chelates formed. The method of continuous variations was necessary to determine first whether, the metal ion and the ligand ethylene diamine form one or more than one chelate, when more than one chelate formed, the results obtained depend on the wavelength and for meaningful conclusions the wavelengths were carefully selected. The empirical formulae of the chelates were further substantiated by the molar ratio method. The effect of time and temperature on the formation and stability of these chelates in solution is also studied. The stability constants, K1 and K2 for the copper (II) chelates were calculated, though reliable, and are comparable to literature values.
基金supported by the Corporation Science and Technology Program of Global Energy Interconnection Group Ltd. (GEIGC-D-[2018]024)by the National Natural Science Foundation of China (61472042, 61772079)
文摘The Global Energy Interconnection is an important strategic approach used to achieve efficient worldwide energy allocation.The idea of developing integrated power,information,and transportation networks provides increased power interconnection functionality and meaning,helps condense forces,and accelerates the integration of global infrastructure.Correspondingly,it is envisaged that it will become the trend of industrial technological development in the future.In consideration of the current trend of integrated development,this study evaluates a possible plan of coordinated development of fiber-optic and power networks in the Pan-Arctic region.Firstly,the backbone network architecture of Global Energy Interconnection is introduced and the importance of the Arctic energy backbone network is confirmed.The energy consumption and developmental trend of global data centers are then analyzed.Subsequently,the global network traffic is predicted and analyzed by means of a polynomial regression model.Finally,in combination with the current construction of fiber-optic networks in the Pan-Arctic region,the advantages of the integration of the fiber-optic and power networks in this region are clarified in justification of the decision for the development of a Global Energy Interconnection scheme.
文摘Ene-chtorination of the otefins bearing isopropenyl moieties has been achieved in good yieid by using catcium hypochiorite and sodium biphosphate. An efficient synthesis of San Jose ScaLe's sex pheromone is described.
文摘To analyze the effects of width and thickness of each composition element of mixed steel U-rib-stiffened plates on the welding residual stress distribution, the distribution of the U-rib and the plate residual stress was calculated using a simplified calculation method. The method involved welding the mixed steel U-rib-stiffened plates for a structure with different sizes and different strength ratios of U-rib to plate. Based on a welding residual stress numerical simulation method validated by the blind hole method test, the distribution law of the mixed steel U-rib stiffened plate was studied. The results showed that the change of plate width has little impact on the welding residual stress and that the ratio of the thicknesses of the plate to U-rib stiffeners, the thickness of the plate, and the thickness of the U-rib has a great influence on the distribution of the welding residual stress. The thickness of plate and steel strength also greatly influenced the distribution width of the residual tensile stress. While analyzing the compression capacity of U-rib-stiffened plates, the simplified distribution of welding residual stress was used.
文摘We investigate the absorption properties of cyclotrimethylene trinitramine(RDX) single crystals from ~15 to150 cm^(-1) using the terahertz time-domain spectroscopy. We observe that all the absorption modes exhibit strong anisotropic behavior in terms of the crystal orientations. We demonstrate that the anharmonic phonon model can well describe the temperature-dependent behaviors of these absorption modes. These results indicate that the intermolecular interaction plays a major role in the collective motion of large number of RDX molecules. Our findings provide important information for understanding and controlling the dynamic properties in the explosive materials.
基金supported by the National Natural Science Foundation of China(Grant No.20072025).
文摘The catalytic performance of a series of cobalt(Ⅱ) hydroxamates (CoL2) and the synergistic catalytic action of the cobalt complexes combined with N-hydroxyphthalimide (NHPI) in the aerobic oxidation of p-xylene to p-toluic acid (PTA) were investigated. The results showed that the existing synergistic action in the catalytic oxidation can shorten the induction period of the radical reaction and improve the yield of PTA.
文摘BACKGROUND Single loop reconstruction(SLR) was routine in our institution for patients undergoing pancreatico-duodenectomy(PD). Roux-en Y reconstruction with an isolated gastric limb(RIGL) recently became the reconstruction of choice.AIM To evaluate the impact of RIGL on incidence and severity of delayed gastric emptying(DGE).METHODS This is a single institution, retrospective analysis of patients undergoing PD. All patients undergoing PD from July 2010 through December 2016 were included in the study. Outcome of RIGL were compared to SLR. Primary measure of outcome included incidence and severity of DGE. Secondary measures of outcome were overall complications and postoperative mortality.RESULTS One hundred and seventy-nine patients were included in the study. Fifty-two had RIGL, 127 had SLR. Overall complication rate was 40.2%, patients in the RIGL group experienced lower rates of DGE(15.4% vs 59.1%, P = 0.001). Other patient related outcomes were also significantly reduced: day of nasogastric tube removal(3 vs 5, P < 0.001), regain of normal diet(8 vs 9, P < 0.001). On multivariate analysis RIGL was associated independently with reduced rates of DGE(P < 0.001, OR 0.14)CONCLUSION The current study shows that RIGL reduces the rate of DGE after PD. Further prospective randomized controlled trials are required to affirm the current data.
基金Project(2007CB613604)supported by the National Basic Research Program of ChinaProject(50674104)supported by the National Natural Science Foundation of China
文摘In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores.The thermodynamic model was constructed and the solubility of malachite Cu2(OH)2CO3 in the ammonia-ammonium chloride-ethylenediamine(En)-water system was calculated using the exponential computation method based on both mass balance and charge balance.It is found that the solubility of copper can be increased and the free ammonia concentration can be decreased by submitting partial ammonia with ethylenediamine.The lower free ammonia concentration in the solution is a guarantee to the lower evaporating rate of ammonia.The conditions of malachite Cu2(OH)2CO3 converting to atacamite Cu(OH)1.5Cl0.5 were also studied.A group of experiments were designed to validate the veracity of the results of the thermodynamic calculation.It is found that the thermodynamic model is reliable and it can guide the leaching process.
文摘observations from the field and the taboratory show that en echelon fractures withinfracture zones have a foede1 within Ricdel structure’ The tensile fallure mecbanism of en echelonfractures can be described by the pile-ups of sbear crack-dislocations. A fractal model can be used tosimulate the Riedel within Xiedel geometry, allowing the direct rneasarement of tbe ftactal dimen sions of en echelon fractare systems. The energy dissipation of tbe en ccbe1on fracture system canbe deduced using a fracil damage evo1ution model which exptalns tbe evo1ution process of en eche lon fracture svstems. The fractal nature of the fractures can be used to dcrive an accurate estimateof total energy dissipation.
文摘New Schiff base Macrocyclic compound of 2,3: 11, 12:20, 21:29, 30-tetrabenzo-1,13,16,19,31,34-hexaoxa-5,6,8,9,23,24,26,27-octaaza-7,25-dithione-2,3:4,5:9,10:11,12:22, 23:27,28:29,30 cyclo-[36]ene (thione2B4[36] ene-O6N8) containing THF has been prepared. It crystallizes in the monoclinic, space group P21/n. with parameters a=9.829(5) b=24.23(1), c=10.181(9), β=92.93(5)°, Z=2, V=2422(3)3, Dc=1.25gcm-3. Data collection: Rigaku AFC-5R diffractometer,(MoKα, λ=0.71069), ω /2θ scans. θmax=25°, empirical absorption correction, 4658 measured reflections, 4387 independent, 1743 observed reflections [I≥3σ(I)]. The final R=0.056. RW=0.069,S=1 .54, (Δ/σ)max=0.01,Δρmax=0.36e-3.
文摘The reaction of (-)-menthyl gloxylate 2 with homoallyl silyl ether 3 under I ewis acid conditions gave optically active one-reaction product 4 with de in a range of 20-45°and 4-chloro-2-hydroxy carboxylate 5 The effect of suloxy group and Lewis acid on the regio- and stereochemistry and distribution of 4 and 5 in the mixture of the product product was examined.
基金support of the "Cooperative Research Program for Agriculture Science and Technology Development(Project No.PJ01175601)" Rural Development Administration,Republic of Korea
文摘field attraction test of (7R,8S)-cis-7,8-epoxy-2- methyloctadec-17-ene (= 7R,8S-epo-2me-17ene-18Hy), a trace component of the sex pheromone gland of the Asian gypsy moth,(Lymantria dispar), traps that were baited with the trace component attracted more L. dispar than traps baited with (7S,8R)-cis-7,8-epoxy-2-methyloctadec-17-ene (= 7S,8R-epo-2me-17ene-18Hy) and unbaited traps. However, traps baited with 7R,8S-epo-2me-17ene-18Hy were less attractive than traps baited with (+)-disparlure [=(7R,8S)-cis-7,8-epoxy-2-methyloctadecane], the sex pheromone of L. dispar. Combination tests with (?)-disparlure, 7R,8S-epo-2me-17ene-18Hy, and 7S,8R-epo-2me- 17ene-18Hy revealed that 7R,8S-epo-2me-17ene-18Hy acted synergistically with (?)-disparlure.
基金Supported by National Natural Science Foundation of China(31101683,31272405)Priority Academic Program Development of Jiangsu Higher Education Institutions(2014)Science and Technology Innovation Fund for Students in Yangzhou University(No.x2015719)
文摘Growth hormone (GH) is a polypeptide hormone secreted by the pituitary, which promotes animal growth, muscle development, metabolism regulation and other important physiological functions. In this study, a pair of mGH short hairpin RNA (shRNA) was designed according to mouse ( Mus musculus) GH mRNA sequence; pSingle-tTS-mGH shRNA-RFP, an integrated controllable expression vector of mGH shRNA, was constructed successfully. The recombinant vector was transfected into mouse pituitary tumor cell line AtT-20. After addition of doxycyelin ( DOX), the expression of red fluorescent protein (RFP) was observed un- der a fluorescent microscope. The expression level of mGH in cells was detected by quantitative Realtime PCR (qRT-PCR) and Western blot. After DOX induction, the relative expression level of GH mRNA in cells transfected with GH shRNA was reduced by about 70% compared with that in DOX-free group and other control groups, exhibiting extremely significant differences (P 〈 0.01 ) ; moreover, the relative expression level of GH protein was reduced by about 90% ; the expression level of GH mRNA and GH protein exhibited no significant difference among other groups (P 〉 0.05). In this study, a controllable expression vector of GH shRNA with high gene silencing efficiency was constructed successfully, which could be used to reveal GH autocfine / paracrine interactions and analyze functions of GH gene in growth, development and disease occurrence of animals by regulating GH expression levels.