Mucinous cystadenoma of the appendix is a rare condition and represents one of the three entities with the common name mucocele of the appendix. It is characterized by a cystic dilatation of the lumen with stasis of m...Mucinous cystadenoma of the appendix is a rare condition and represents one of the three entities with the common name mucocele of the appendix. It is characterized by a cystic dilatation of the lumen with stasis of mucus inside it. Histopathologically mucocele is divided into three groups： focal or diffuse mucosal hyperplasia, mucinous cystadenoma and mucinous cystadenocarcinoma. This condition is often associated with other neoplasia, especially adenocarcinoma of the colon and ovaries. We here describe a 57 year old male patient who presented with abdominal discomfort, constipation, fresh blood in stool and frequent urination. He had a big cystadenoma of the appendix associated with adenocarcinoma of the colon and hepatocellular carcinoma of the liver. The patient underwent right haemicolectomy, sigmoid colon resection and segmental resection of the liven Now 3 years later he has no evidence of disease relapse. According to this, we stress the need of accurate preoperative diagnosis and intraoperative exploration of the whole abdomen in these patients.展开更多
Adrenal pseudocysts are rare cystic masses that arise within the adrenal gland and are usually non-functional and asymptomatic. Adrenal pseudocysts consist of a fibrous wall without a cellular lining. We report a pati...Adrenal pseudocysts are rare cystic masses that arise within the adrenal gland and are usually non-functional and asymptomatic. Adrenal pseudocysts consist of a fibrous wall without a cellular lining. We report a patient with a 9 cm, left-sided suprarenal cystic mass who presented with abdominal discomfort of 2 years＇ duration. A 38-year-old woman was referred to our service for evaluation of abdominal discomfort and gastrointestinal symptoms. Routine laboratory tests were within normal limits. An abdominal computed tomography scan showed a 9 cm × 8 cm × 8 cm well-defined cystic lesion displacing the left kidney. Magnetic resonance imaging showed a cystic lesion with low signal intensity on the Tl-weighted image and high signal intensity on the T2-weighted image. A laparoscopic left adrenalectomy was performed to diagnose the lesion. The final pathology showed an adrenal pseudocyst without a cellular lining. The patient had no postoperative complications and she was discharged four days after surgery.展开更多
A new fluid bag buffer mechanism,which can provide large axial stiffness under the small displacement,is designed.The dynamic change laws of the mechanism stiffness and the internal pressure of the fluid bag are studi...A new fluid bag buffer mechanism,which can provide large axial stiffness under the small displacement,is designed.The dynamic change laws of the mechanism stiffness and the internal pressure of the fluid bag are studied when it is subjected to impact load.According to the protection performance for the flexible joint and the pressure change in the fluid bag during the impact process,the sensitivity of the geometric parameters of the fluid bag to the axial stiffness is analyzed by using the orthogonal experimental method,and the optimal parameter combination of the geometric parameters of the fluid bag under impact is obtained,leading to the displacement of the inner shell reduce by 41.4%.The results show that the internal pressure of the fluid bag is a rising process of oscillation and fluctuation.The sensitivity of the geometric parameters of the fluid bag to the displacement of the inner shell from high to low is as follows:Height H,radius r,wall thickness t,chamfer A.The correlation between the geometric parameters of the fluid bag and its internal pressure is:H is negatively correlated with the internal pressure,while the r,t,and A are positively correlated with the internal pressure.展开更多
Primary retroperitoneal mucinous cystadenomas (RMCs) are very rare and their biological behavior and histogenesis remain speculative. An accurate preoperative diagnosis of these tumors is difficult because no effectiv...Primary retroperitoneal mucinous cystadenomas (RMCs) are very rare and their biological behavior and histogenesis remain speculative. An accurate preoperative diagnosis of these tumors is difficult because no effective diagnostic measures have been established. We describe a 29-year-old woman with abdominal pain and a palpable mass. Computed tomography (CT) of the abdomen revealed a retroperi-toneal cystic mass which was resected successfully at laparotomy. Histopathological examination of the resected mass confirmed the diagnosis of RMC. There was no evidence of disease 2 years after surgery.展开更多
Mucocoele of the appendix occurs when obstruction of the appendiceal lumen results in mucus accumulation and consequent abnormal dilatation. The most impor- tant aetiology, from a surgical perspective, is either mucin...Mucocoele of the appendix occurs when obstruction of the appendiceal lumen results in mucus accumulation and consequent abnormal dilatation. The most impor- tant aetiology, from a surgical perspective, is either mucinous cystadenoma or cystadenocarcinoma. In the latter, a spontaneous or iatrogenic rupture of the mucocoele can lead to mucinous intraperitoneal ascites, a syndrome known as pseudomyxoma peritonei. Optimal management of mucoceles is achieved through accurate preoperative identification and subsequent careful resection. We report two cases and subsequently discuss the clinical presentation of mucocoeles, their association with pseudomyxoma peritonei and an optimal management of both conditions.展开更多
A buffer bag mechanism is designed,which can provide axial impact protection under small displacement.The stiffness characteristics of the structure under impact load are studied.The stiffness of the mechanism and the...A buffer bag mechanism is designed,which can provide axial impact protection under small displacement.The stiffness characteristics of the structure under impact load are studied.The stiffness of the mechanism and the internal pressure change of the buffer bag are compared and analyzed,when the filling materials are liquid and gas respectively.Finally,the influence of initial fluid bag pressure,bulk modulus and shell thickness on the stiffness of the mechanism and the change of bag pressure are studied.The results show that the stiffness of the liquid bag is better than that of the gas bag when the filler is liquid and gas;the liquid bag has obvious pressure rise after the mechanism is subjected to axial force by 300 kN,and the gas bag has almost no pressure rise;the change of bulk modulus,which is1000,1500,2000 and 2500 MPa,has an obvious effect on the liquid bag,and it is positively correlated with the stiffness of the mechanism.The change of gas modulus,which is 28 and 44,has little effect on the stiffness of the mechanism;the thickness of the buffer bag,which is 5,10 and 15 mm,also has an obvious effect on the stiffness.The stiffness of the liquid bag is greater,and the protection for flexible joint is better in the same condition.展开更多
Solitary pancreatic involvement of tuberculosis is rare, especially in an immunocompetent individual, and it may be misdiagnosed as pancreatic cystic neoplasms. Pancreatic cystic neoplasms are being identified in incr...Solitary pancreatic involvement of tuberculosis is rare, especially in an immunocompetent individual, and it may be misdiagnosed as pancreatic cystic neoplasms. Pancreatic cystic neoplasms are being identified in increasing numbers, probably because of the frequent use of radiology and advances in endoscopic techniques. However, they are composed of a variety of neoplasms with a wide range of malignant potential, and it is often difficult to differentiate pancreatic tuberculosis mimicking cystic neoplasms from benign or malignant pancreatic cystic neoplasms. Non-surgical diagnosis of pancreatic tuberculosis is inconclusive and continues to be a challenge in many cases. If so, then laparotomy should be employed to establish the diagnosis. Therefore, pancreatic tuberculosis should be kept in mind during the differential diagnosis of solitary cystic masses in the pancreas. We report a patient who had solitary pancreatic tuberculosis masquerading as pancreatic serous cystadenoma.展开更多
In this study, magnetic core–shell structure Fe3O4@MCM-41 nanoparticles were synthesized with vesicles as soft templates. In the preparation, Fe Cl2 and tetraethy orthosilicate(TEOS) were selected as Fe processor and...In this study, magnetic core–shell structure Fe3O4@MCM-41 nanoparticles were synthesized with vesicles as soft templates. In the preparation, Fe Cl2 and tetraethy orthosilicate(TEOS) were selected as Fe processor and Si precursor, respectively. Stable vesicles first formed in 0.03 mol·L-11:2 mixture of anionic surfactant sodium dodecyl sulfate and cationic surfactant cetyltrimethyl ammonium bromide. Then, TEOS was added in the vesicle aqueous solution, leading to a highly dispersed solution. After high-temperature calcination, Fe3O4@MCM-41 nanoparticles were obtained. Their structure and morphology were characterized by Saturn Digisizer, transmission electron microscope and vibrating sample magneto-meter. The results indicate that the vesicles are spherical and their size could be tuned between 20 and 50 nm. The average grain diameter of synthesize magnetic core–shell Fe3O4@MCM-41 particles is 100–150 nm and most of them are in elliptical shape. The dispersion of magnetic particles is very good and magnetization values are up to 33.44 emu·g-1, which are superior to that of other Fe3O4 materials reported.展开更多
A hull structure is prone to local deformation and damage due to the pressure load on the surface.How to simulate surface pressure is an important issue in ship structure test.The loading mode of hydraulic actuator co...A hull structure is prone to local deformation and damage due to the pressure load on the surface.How to simulate surface pressure is an important issue in ship structure test.The loading mode of hydraulic actuator combined with high-pressure flexible bladder was proposed,and the numerical model of the loading device based on flexible bladder was established.The design and analysis method of high-pressure flexible bladder based on aramid-fiber reinforced thermoplastic polyurethane was proposed to break through the surface pressure loading technology of ship structures.The surface pressure loading system based on flexible bladder was developed.The ultimate strength verification test of the box girder under the combined action of bending moment and pressure was carried out to systematically verify the feasibility and applicability of the loading system.The results show that the surface pressure loading technology can be used well for applying uniform pressure to ship structures.Compared with the traditional surface loading methods,the improved device can be applied with horizontal constant pressure load,with rapid response and safe process,and the pressure load is always stable with the increase of the bending moment load during the test.The requirement for uniform loading in the comprehensive strength test of large structural models is satisfied and the accuracy of the test results is improved by this system.展开更多
The original 1992 Atlanta Classification Systemfor acute pancreatitis was revised in 2012 by the Atlanta Working Group,assisted by various national and international societies,through web-based consensus.This revised ...The original 1992 Atlanta Classification Systemfor acute pancreatitis was revised in 2012 by the Atlanta Working Group,assisted by various national and international societies,through web-based consensus.This revised classification identifies two phases of acute pancreatitis:early and late.Acute pancreatitis can be either oedematous interstitial pancreatitis or necrotizing pancreatitis.Severity of the disease is categorized into three levels:mild,moderately severe and severe,depending upon organ failure and local/systemic complications.According to the type of pancreatitis,collections are further divided into acute peripancreatic fluid collection,pseudocyst,acute necrotic collection,and walled-off necrosis.Insight into the revised terminology is essential for accurate communication of imaging findings.In this review article,we will summarize the updated nomenclature and illustrate corresponding imaging findings using examples.展开更多
文摘Mucinous cystadenoma of the appendix is a rare condition and represents one of the three entities with the common name mucocele of the appendix. It is characterized by a cystic dilatation of the lumen with stasis of mucus inside it. Histopathologically mucocele is divided into three groups： focal or diffuse mucosal hyperplasia, mucinous cystadenoma and mucinous cystadenocarcinoma. This condition is often associated with other neoplasia, especially adenocarcinoma of the colon and ovaries. We here describe a 57 year old male patient who presented with abdominal discomfort, constipation, fresh blood in stool and frequent urination. He had a big cystadenoma of the appendix associated with adenocarcinoma of the colon and hepatocellular carcinoma of the liver. The patient underwent right haemicolectomy, sigmoid colon resection and segmental resection of the liven Now 3 years later he has no evidence of disease relapse. According to this, we stress the need of accurate preoperative diagnosis and intraoperative exploration of the whole abdomen in these patients.
文摘Adrenal pseudocysts are rare cystic masses that arise within the adrenal gland and are usually non-functional and asymptomatic. Adrenal pseudocysts consist of a fibrous wall without a cellular lining. We report a patient with a 9 cm, left-sided suprarenal cystic mass who presented with abdominal discomfort of 2 years＇ duration. A 38-year-old woman was referred to our service for evaluation of abdominal discomfort and gastrointestinal symptoms. Routine laboratory tests were within normal limits. An abdominal computed tomography scan showed a 9 cm × 8 cm × 8 cm well-defined cystic lesion displacing the left kidney. Magnetic resonance imaging showed a cystic lesion with low signal intensity on the Tl-weighted image and high signal intensity on the T2-weighted image. A laparoscopic left adrenalectomy was performed to diagnose the lesion. The final pathology showed an adrenal pseudocyst without a cellular lining. The patient had no postoperative complications and she was discharged four days after surgery.
基金supported by the Fun⁃damental Scientific Research Business Expenses of Central Universities(No.NJ2020024).
文摘A new fluid bag buffer mechanism,which can provide large axial stiffness under the small displacement,is designed.The dynamic change laws of the mechanism stiffness and the internal pressure of the fluid bag are studied when it is subjected to impact load.According to the protection performance for the flexible joint and the pressure change in the fluid bag during the impact process,the sensitivity of the geometric parameters of the fluid bag to the axial stiffness is analyzed by using the orthogonal experimental method,and the optimal parameter combination of the geometric parameters of the fluid bag under impact is obtained,leading to the displacement of the inner shell reduce by 41.4%.The results show that the internal pressure of the fluid bag is a rising process of oscillation and fluctuation.The sensitivity of the geometric parameters of the fluid bag to the displacement of the inner shell from high to low is as follows:Height H,radius r,wall thickness t,chamfer A.The correlation between the geometric parameters of the fluid bag and its internal pressure is:H is negatively correlated with the internal pressure,while the r,t,and A are positively correlated with the internal pressure.
文摘Primary retroperitoneal mucinous cystadenomas (RMCs) are very rare and their biological behavior and histogenesis remain speculative. An accurate preoperative diagnosis of these tumors is difficult because no effective diagnostic measures have been established. We describe a 29-year-old woman with abdominal pain and a palpable mass. Computed tomography (CT) of the abdomen revealed a retroperi-toneal cystic mass which was resected successfully at laparotomy. Histopathological examination of the resected mass confirmed the diagnosis of RMC. There was no evidence of disease 2 years after surgery.
文摘Mucocoele of the appendix occurs when obstruction of the appendiceal lumen results in mucus accumulation and consequent abnormal dilatation. The most impor- tant aetiology, from a surgical perspective, is either mucinous cystadenoma or cystadenocarcinoma. In the latter, a spontaneous or iatrogenic rupture of the mucocoele can lead to mucinous intraperitoneal ascites, a syndrome known as pseudomyxoma peritonei. Optimal management of mucoceles is achieved through accurate preoperative identification and subsequent careful resection. We report two cases and subsequently discuss the clinical presentation of mucocoeles, their association with pseudomyxoma peritonei and an optimal management of both conditions.
基金supported by the Fundamental Research Funds for the Central Universities(No.NS2019003)。
文摘A buffer bag mechanism is designed,which can provide axial impact protection under small displacement.The stiffness characteristics of the structure under impact load are studied.The stiffness of the mechanism and the internal pressure change of the buffer bag are compared and analyzed,when the filling materials are liquid and gas respectively.Finally,the influence of initial fluid bag pressure,bulk modulus and shell thickness on the stiffness of the mechanism and the change of bag pressure are studied.The results show that the stiffness of the liquid bag is better than that of the gas bag when the filler is liquid and gas;the liquid bag has obvious pressure rise after the mechanism is subjected to axial force by 300 kN,and the gas bag has almost no pressure rise;the change of bulk modulus,which is1000,1500,2000 and 2500 MPa,has an obvious effect on the liquid bag,and it is positively correlated with the stiffness of the mechanism.The change of gas modulus,which is 28 and 44,has little effect on the stiffness of the mechanism;the thickness of the buffer bag,which is 5,10 and 15 mm,also has an obvious effect on the stiffness.The stiffness of the liquid bag is greater,and the protection for flexible joint is better in the same condition.
文摘Solitary pancreatic involvement of tuberculosis is rare, especially in an immunocompetent individual, and it may be misdiagnosed as pancreatic cystic neoplasms. Pancreatic cystic neoplasms are being identified in increasing numbers, probably because of the frequent use of radiology and advances in endoscopic techniques. However, they are composed of a variety of neoplasms with a wide range of malignant potential, and it is often difficult to differentiate pancreatic tuberculosis mimicking cystic neoplasms from benign or malignant pancreatic cystic neoplasms. Non-surgical diagnosis of pancreatic tuberculosis is inconclusive and continues to be a challenge in many cases. If so, then laparotomy should be employed to establish the diagnosis. Therefore, pancreatic tuberculosis should be kept in mind during the differential diagnosis of solitary cystic masses in the pancreas. We report a patient who had solitary pancreatic tuberculosis masquerading as pancreatic serous cystadenoma.
基金Supported by the Natural Science Foundation of Heilongjiang Province(B201010)the Education Department of Heilongjiang Province(12511595)
文摘In this study, magnetic core–shell structure Fe3O4@MCM-41 nanoparticles were synthesized with vesicles as soft templates. In the preparation, Fe Cl2 and tetraethy orthosilicate(TEOS) were selected as Fe processor and Si precursor, respectively. Stable vesicles first formed in 0.03 mol·L-11:2 mixture of anionic surfactant sodium dodecyl sulfate and cationic surfactant cetyltrimethyl ammonium bromide. Then, TEOS was added in the vesicle aqueous solution, leading to a highly dispersed solution. After high-temperature calcination, Fe3O4@MCM-41 nanoparticles were obtained. Their structure and morphology were characterized by Saturn Digisizer, transmission electron microscope and vibrating sample magneto-meter. The results indicate that the vesicles are spherical and their size could be tuned between 20 and 50 nm. The average grain diameter of synthesize magnetic core–shell Fe3O4@MCM-41 particles is 100–150 nm and most of them are in elliptical shape. The dispersion of magnetic particles is very good and magnetization values are up to 33.44 emu·g-1, which are superior to that of other Fe3O4 materials reported.
文摘A hull structure is prone to local deformation and damage due to the pressure load on the surface.How to simulate surface pressure is an important issue in ship structure test.The loading mode of hydraulic actuator combined with high-pressure flexible bladder was proposed,and the numerical model of the loading device based on flexible bladder was established.The design and analysis method of high-pressure flexible bladder based on aramid-fiber reinforced thermoplastic polyurethane was proposed to break through the surface pressure loading technology of ship structures.The surface pressure loading system based on flexible bladder was developed.The ultimate strength verification test of the box girder under the combined action of bending moment and pressure was carried out to systematically verify the feasibility and applicability of the loading system.The results show that the surface pressure loading technology can be used well for applying uniform pressure to ship structures.Compared with the traditional surface loading methods,the improved device can be applied with horizontal constant pressure load,with rapid response and safe process,and the pressure load is always stable with the increase of the bending moment load during the test.The requirement for uniform loading in the comprehensive strength test of large structural models is satisfied and the accuracy of the test results is improved by this system.
文摘The original 1992 Atlanta Classification Systemfor acute pancreatitis was revised in 2012 by the Atlanta Working Group,assisted by various national and international societies,through web-based consensus.This revised classification identifies two phases of acute pancreatitis:early and late.Acute pancreatitis can be either oedematous interstitial pancreatitis or necrotizing pancreatitis.Severity of the disease is categorized into three levels:mild,moderately severe and severe,depending upon organ failure and local/systemic complications.According to the type of pancreatitis,collections are further divided into acute peripancreatic fluid collection,pseudocyst,acute necrotic collection,and walled-off necrosis.Insight into the revised terminology is essential for accurate communication of imaging findings.In this review article,we will summarize the updated nomenclature and illustrate corresponding imaging findings using examples.
