Six human embryonic stem cell lines were established from surplus blastocysts. The cell lines expressed alkaline phosphatase and molecules typical of primate embryonic stem cells, including Oct-4, Nanog, TDGF1, Sox2, ...Six human embryonic stem cell lines were established from surplus blastocysts. The cell lines expressed alkaline phosphatase and molecules typical of primate embryonic stem cells, including Oct-4, Nanog, TDGF1, Sox2, EBAF, Thy-1, FGF4, Rex-1, SSEA-3, SSEA-4, TRA-1-60 and TRA-1-81. Five of the six lines formed embryoid bodies that expressed markers of a variety of cell types; four of them formed teratomas with tissue types representative of all three embryonic germ layers. These human embryonic stem cells are capable of producing clones of undifferentiated morphology, and one of them was propagated to become a subline. Human embryonic stem cell lines from the Chinese population should facilitate stem cell research and may be valuable in studies of population genetics and ecology.展开更多
AIM: Direct neoplastic invasion of esophageal inlet is an uncommon but significant sequela of advanced head and neck carcinomas. The aim of this study was to seek an optimal CT or MRI criterion for determining the neo...AIM: Direct neoplastic invasion of esophageal inlet is an uncommon but significant sequela of advanced head and neck carcinomas. The aim of this study was to seek an optimal CT or MRI criterion for determining the neoplastic esophageal inlet involvement in order to help tumor staging and surgical planning. METHODS: CT and MRI of 78 head and neck tumor cases were investigated retrospectively. At the level of the esophageal inlet on axial CT and MRI scans, the distance between the posterior aspect of cricoid cartilage and the anterior aspect of vertebra (d-CV) was measured by two senior radiologists who were unaware of clinical findings. Then, according to pathologie evidence and follow-up findings, these patients were divided into patients group, including 32 cases with neoplastic invasion of esophageal inlet and control group, including 46 cases without neoplastic esophageal inlet involvement. The statistical difference based on d-CV between the two groups was determined. The optimal criterion of d-CV on CT or MRI was assessed and lts accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were evaluated respectively. RESULTS: In control group, d-CV at the esophageal inlet level was 0.94±0.15 cm on axial CT and 0.91±0.18 cm on axial MRI, whereas in patient group, d-CV was 1.24±0.32 cm on CT and 1.31±0.36 cm on MRI. There was a statistical significance in d-CV between the two groups on CT and MRI modalities (P<0.01). d-CV greater than 1.0 cm was the typicall feature of neoplastic invasion of the esophageal inlet with 73% sensitivity, 83% specificity, 79% accuracy, 76% PPV, 80% NPV on CT and 84% sensitivity, 77% specificity, 80% accuracy, 70% PPV, 88% NPV on MRI respectively. CONCLUSION: Except for other CT and MR imaging features of neoplastic invasion of esophageal inlet, d-CV greater than 1.0 cm is an optimal adjunct criterion for esophageal inlet invasion by advanced head and neck carcinomas.展开更多
The nonlinear models of the elastic and elastic-linear strain-hardening square plates with four immovably simply-supported edges are established by employing Hamiltons Variational Principle in a uniform temperature fi...The nonlinear models of the elastic and elastic-linear strain-hardening square plates with four immovably simply-supported edges are established by employing Hamiltons Variational Principle in a uniform temperature field. The unilateral equilibrium equations satisfied by the plastically buckled equilibria are also established. Dynamics and stability of the elastic and plastic plates are investigated analytically and the buckled equilibria are investigated by employing Galerkin-Ritzs method. The vibration frequencies, the first critical temperature differences of instability or buckling, the elastically buckled equilibria and the extremes depending on the final loading temperature difference of the plastically buckled equillibria of the plate are obtained. The results indicate that the critical buckling value of the plastic plate is lower than its critical instability value and the critical value of its buckled equilibria turning back to the trivial equilibrium are higher than the value. However, three critical values of the elastic plate are equal. The unidirectional snap-through may occur both at the stress-strain boundary of elasticity and plasticity and at the initial stage of unloading of the plastic plate.展开更多
AIM: To highlight the intestinal perforation (IP), an uncommon and catastrophic complication after combined liver-kidney transplantation.METHODS: Combined liver-kidney transplantation (LKTx) with left kidney excision ...AIM: To highlight the intestinal perforation (IP), an uncommon and catastrophic complication after combined liver-kidney transplantation.METHODS: Combined liver-kidney transplantation (LKTx) with left kidney excision and a cyst fenestration procedure on the right kidney were performed on a case of 46-year-old female with congenital polycystic disease (CPCD).RESULTS: Two sites of IP were noted 40-50 cm proximal to ileocecal area during emergent laparotomy 10 d postoperatively.Despite aggressive surgical and medical management,disease progressed toward a fatal outcome due to sepsis and multiple organ failure 11 d later.CONCLUSION: Long duration of operation without venovenous bypass, overdose of steroid together with postoperative volume excess may all contribute to the risk of idiopathic multiple IPs. Microbiology and pathology inspections suggested that the infected cyst of the fenestrated kidney might be one reason for the fatal intra-peritoneal infection. Thus for the CPCD patients who seem to be very susceptible to infectious complications, any sign of suspected renal-infection found before or during LKTx is indication for the excision of original kidney. And the intensity of immunosuppression therapy should be controlled cautiously.展开更多
基金This work was supported by grants from National Ba-sic Research Program of China(973 Program)(No:001CB509903,001CB509904)Hi-Tech Research and Development Program of China(973 Program)(No:2001A A216121.2004AA205010)+3 种基金National Natural Science Foun-dation of China(No:30040003)Science and Technology Committee of Shanghai Municipality(No:99DJ 14002,00DJI 4033,0IDJ 14003.03DJ 14017)Chinese Academy of Science(No:KSCX-2-3-08)Shanghai Municipal Edu-cation Commission and Shanghai Second Medical University.
文摘Six human embryonic stem cell lines were established from surplus blastocysts. The cell lines expressed alkaline phosphatase and molecules typical of primate embryonic stem cells, including Oct-4, Nanog, TDGF1, Sox2, EBAF, Thy-1, FGF4, Rex-1, SSEA-3, SSEA-4, TRA-1-60 and TRA-1-81. Five of the six lines formed embryoid bodies that expressed markers of a variety of cell types; four of them formed teratomas with tissue types representative of all three embryonic germ layers. These human embryonic stem cells are capable of producing clones of undifferentiated morphology, and one of them was propagated to become a subline. Human embryonic stem cell lines from the Chinese population should facilitate stem cell research and may be valuable in studies of population genetics and ecology.
文摘AIM: Direct neoplastic invasion of esophageal inlet is an uncommon but significant sequela of advanced head and neck carcinomas. The aim of this study was to seek an optimal CT or MRI criterion for determining the neoplastic esophageal inlet involvement in order to help tumor staging and surgical planning. METHODS: CT and MRI of 78 head and neck tumor cases were investigated retrospectively. At the level of the esophageal inlet on axial CT and MRI scans, the distance between the posterior aspect of cricoid cartilage and the anterior aspect of vertebra (d-CV) was measured by two senior radiologists who were unaware of clinical findings. Then, according to pathologie evidence and follow-up findings, these patients were divided into patients group, including 32 cases with neoplastic invasion of esophageal inlet and control group, including 46 cases without neoplastic esophageal inlet involvement. The statistical difference based on d-CV between the two groups was determined. The optimal criterion of d-CV on CT or MRI was assessed and lts accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were evaluated respectively. RESULTS: In control group, d-CV at the esophageal inlet level was 0.94±0.15 cm on axial CT and 0.91±0.18 cm on axial MRI, whereas in patient group, d-CV was 1.24±0.32 cm on CT and 1.31±0.36 cm on MRI. There was a statistical significance in d-CV between the two groups on CT and MRI modalities (P<0.01). d-CV greater than 1.0 cm was the typicall feature of neoplastic invasion of the esophageal inlet with 73% sensitivity, 83% specificity, 79% accuracy, 76% PPV, 80% NPV on CT and 84% sensitivity, 77% specificity, 80% accuracy, 70% PPV, 88% NPV on MRI respectively. CONCLUSION: Except for other CT and MR imaging features of neoplastic invasion of esophageal inlet, d-CV greater than 1.0 cm is an optimal adjunct criterion for esophageal inlet invasion by advanced head and neck carcinomas.
基金The project supported by the National Natural Science Foundation of China(10272002)the Doctoral Program from the Ministry of Education of China(20020001032)
文摘The nonlinear models of the elastic and elastic-linear strain-hardening square plates with four immovably simply-supported edges are established by employing Hamiltons Variational Principle in a uniform temperature field. The unilateral equilibrium equations satisfied by the plastically buckled equilibria are also established. Dynamics and stability of the elastic and plastic plates are investigated analytically and the buckled equilibria are investigated by employing Galerkin-Ritzs method. The vibration frequencies, the first critical temperature differences of instability or buckling, the elastically buckled equilibria and the extremes depending on the final loading temperature difference of the plastically buckled equillibria of the plate are obtained. The results indicate that the critical buckling value of the plastic plate is lower than its critical instability value and the critical value of its buckled equilibria turning back to the trivial equilibrium are higher than the value. However, three critical values of the elastic plate are equal. The unidirectional snap-through may occur both at the stress-strain boundary of elasticity and plasticity and at the initial stage of unloading of the plastic plate.
文摘AIM: To highlight the intestinal perforation (IP), an uncommon and catastrophic complication after combined liver-kidney transplantation.METHODS: Combined liver-kidney transplantation (LKTx) with left kidney excision and a cyst fenestration procedure on the right kidney were performed on a case of 46-year-old female with congenital polycystic disease (CPCD).RESULTS: Two sites of IP were noted 40-50 cm proximal to ileocecal area during emergent laparotomy 10 d postoperatively.Despite aggressive surgical and medical management,disease progressed toward a fatal outcome due to sepsis and multiple organ failure 11 d later.CONCLUSION: Long duration of operation without venovenous bypass, overdose of steroid together with postoperative volume excess may all contribute to the risk of idiopathic multiple IPs. Microbiology and pathology inspections suggested that the infected cyst of the fenestrated kidney might be one reason for the fatal intra-peritoneal infection. Thus for the CPCD patients who seem to be very susceptible to infectious complications, any sign of suspected renal-infection found before or during LKTx is indication for the excision of original kidney. And the intensity of immunosuppression therapy should be controlled cautiously.
