In machining the particle reinforced aluminum based composite material with high Si content using the cobalt-cemented tungsten carbide micro cutting tools, diamond like carbon (DLC) films are deposited on cobalt-cem...In machining the particle reinforced aluminum based composite material with high Si content using the cobalt-cemented tungsten carbide micro cutting tools, diamond like carbon (DLC) films are deposited on cobalt-cemented tungsten carbide micro-drills with two-step pretreatment method. Characteristics of DLC coated tools are investigated in bias-enhanced HFCVD system with the optimized hot filament arrangement. The optimization deposition technology is obtained and the wear mechanism of cutting tools is analyzed. The drilling performance of DLC coated tools is verified by the experiments of cutting particle reinforced aluminum based composite material (Si 15% in volume) compared with uncoated ones. Experimental results show that the two-step pretreatment method is appropriate for complex shaped cemented carbide substrates and ensures the good adhesive strength between the diamond film and the substrate. The cutting performance of DLC coated tool is enhanced 10 times when machining the Si particle reinforced aluminum based metal matrix composite compared with that of uncoated ones under the same cutting conditions.展开更多
A computer aided measurement system is used to measure the cutting temperature directly in high-speed machining by natural thermocouples and standard thermocouples. In this system the tool/workpiece interface temperat...A computer aided measurement system is used to measure the cutting temperature directly in high-speed machining by natural thermocouples and standard thermocouples. In this system the tool/workpiece interface temperature is measured by the tool/workpiece natural thermocouple, while the temperature distribution on the workpiece surface and that of interior are measured by some standard thermocouples prearranged at proper positions. The system can be used to measure cutting temperature in the machining with the rotary cutting tools, such as vertical drill and end milling cutter. It is practically used for the research on high-speed milling with hardened steel.展开更多
The thrust and the torque of various carbide drills are studied for the high-speed drilling of fiber reinforced epoxy composites. The orthogonal experiment is carried out with different feed speeds at high rotation sp...The thrust and the torque of various carbide drills are studied for the high-speed drilling of fiber reinforced epoxy composites. The orthogonal experiment is carried out with different feed speeds at high rotation speed. Experimental results show that the spindle rotation speed is the most influential factor. The thrust andthe torque decrease under the condition of high rotation rate. With the decrease of the feed speed, the thrust and the torque decrease. But the effect of the feed speed is less than that of the spindle rotation rate. Moreover, the effect of drill materials on the thrust and the torque is more notable than that of the drill geometries and the feed speed. The thrust is greatly affected by the feed speed while the torque is obviously affected by drill geometries.展开更多
Target made of 2519-T87 aluminum alloy was obliquely impacted by a projectile. Microstructural evolution around the crater was investigated by optical microscopy (OM), transmission electron microscopy (TEM), and e...Target made of 2519-T87 aluminum alloy was obliquely impacted by a projectile. Microstructural evolution around the crater was investigated by optical microscopy (OM), transmission electron microscopy (TEM), and electron backscattered diffraction (EBSD). The micro-hardness distribution near the crater after impact was studied. The results indicate that at the entering stage, the amount of adiabatic shear band (ASB) is the most, and the precipitates are as fine as those of the target material; the micro-hardness is higher than that at the other stages. At the stable-running stage, the amount of ASB reduces as the micro-bands increase; the precipitates tend to coarsen, which leads to the decrease of the micro-hardness. At the leaving stage, there is a large amount of micro-bands; the precipitates are refined, and the micro-hardness is higher than that at the stable-running stage. The difference in the micro-hardness of the impact stages is due to work hardening and precipitate coarsening, which is caused by adiabatic temperature rise in the alloy.展开更多
Fatigue cutting is a new approach for separating material. Man-made fatigue can be realized by applying a rotating bending load to a notched bar. To better utilize the new method, laser treatment is adopted in this st...Fatigue cutting is a new approach for separating material. Man-made fatigue can be realized by applying a rotating bending load to a notched bar. To better utilize the new method, laser treatment is adopted in this study. After laser radiation at the notch root, the fatigue cycle of the bar drops dramatically. Based on the experimental result, we draw the conclusion that the fatigue of the bar is influenced by the shape of the hardened area. A hardened area that has a small axial dimension and a relatively large radial dimension facilitates the fatigue. The desirable hardened area can be obtained by controlling the laser treatment parameters.展开更多
AIM: To develop a simplified and quick protocol to induce cirrhosis and standardize models of partial liver resection in rats. METHODS: In Fischer F344 rats two modified protocols of phenobarbital-carbon tetrachlori...AIM: To develop a simplified and quick protocol to induce cirrhosis and standardize models of partial liver resection in rats. METHODS: In Fischer F344 rats two modified protocols of phenobarbital-carbon tetrachloride (CCl4) (dilution 50%) gavage to induce cirrhosis (frequency adjusted according to weight, but each subsequent dose was systematically administered) were tested, i.e. the rapid and slow protocols. Prothrombin time (PT) and total bilirubin (TB) were also evaluated. Animals from the rapid group underwent 15% hepatectomy and animals from the slow group underwent 70% hepatectomy. RESULTS: Rapid protocol: This corresponded to 1 gavage/4 d over 6 wk (mortality 30%). Mean PT was 35.2 ±2.8 s (normal: ld.5 s), and mean TB was 1.8 ± 0.2 mg/dL (normal: 0.1 mg/dL). Slow protocol: This cop responded to 1 gavage/6 d over 9 wk (mortality 10%). Mean PT was 11.8 ± 0.2 s (normal: 14.5 s), and mean TB was 0.4 ± 0.04 mg/dL (normal: 0.1 mg/dL). Pathological analyses were performed in both protocols which showed persistent cirrhosis at 3 mo. Rat mortality in the rapid garage group who underwent 15% hepatectomy and in the slow garage group who underwent 70% hepatectomy was 50% and 70%, respectively, CONCLUSION: Our modified model is a simplified method to induce cirrhosis which is rapid (6 to 9 wk), efficient and stable up to 3 mo. Using this method, "Child Pugh A" or "Child Pugh BC" cirrhotic rats were obtained. Our models of cirrhosis and hepatectomy can be used in various situations focusing on postoperative survival.展开更多
AIM: To explore the feasibility of performing gastrectomy with D2 lymphadenectomy in gastric cancer patients with liver cirrhosis. METHODS: A total of 7 178 patients were admitted with a diagnosis of liver cirrhosis...AIM: To explore the feasibility of performing gastrectomy with D2 lymphadenectomy in gastric cancer patients with liver cirrhosis. METHODS: A total of 7 178 patients were admitted with a diagnosis of liver cirrhosis from January 1993 to December 2003. We reviewed the records of 142 patients who were diagnosed with liver cirrhosis and gastric adenocarcinoma during the same period. Gastrectomy with D2 lymph node dissection for carcinoma of the stomach was performed in 94 patients with histologically proven hepatic cirrhosis. RESULTS: All but 12 patients were dassified as Child's class A. Only 35 patients (37.2%) were diagnosed with cirrhosis before operation. Seventy-three patients underwent a subtotal gastrectomy (77.7%) and 21 patients (22.3%) underwent a total gastrectomy, each with D2 or more lymph node dissection. Two patients (3.8%) who had prophylactic intra-operative drain placement, died of postoperative complications from hepatorenal failure with intractable ascites. Thirty-seven patients (39.4%) experienced postoperative complications. The extent of gastric resection did not influence the morbidity whereas serum aspartate aminotransferase level (P = 0.011) and transfusion did (P = 0.008). The most common postoperative complication was ascites (13.9%) followed by wound infection (10.6%). CONCLUSION: We concluded that the presence of compensated cirrhosis, i.e. Child class A, is not a contraindication against gastrectomy with D2 or more lymph node dissection, when curative resection for gastric cancer is possible. Hepatic reserve and meticulous hemostasis are the likely determinants of operative prognosis.展开更多
Hepatocellular carcinoma(HCC) is one of the most frequent neoplasms worldwide and in most cases it is associated with liver cirrhosis.Liver resection is considered the most potentially curative therapy for HCC patient...Hepatocellular carcinoma(HCC) is one of the most frequent neoplasms worldwide and in most cases it is associated with liver cirrhosis.Liver resection is considered the most potentially curative therapy for HCC patients when liver transplantation is not an option or is not immediately accessible.This review is aimed at investigating the current concepts that drive the surgical choice in the treatment of HCC in cirrhotic patients;Eastern and Western perspectives are highlighted.An extensive literature review of the last two decades was performed,on topics covering various aspects of hepatic resection.Early post-operative and long-term outcome measures adopted were firstly analyzed in an attempt to define an optimal standardization useful for research comparison.The need to avoid the development of post-hepatectomy liver failure represents the "conditio sine qua non" of surgical choice and the role of the current tools available for the assessment of liver function reserve were investigated.Results of hepatic resection in relationship with tumor burden were compared with those of available competing strategies,namely,radiofrequency ablation for early stages,and trans-arterial chemoembolization for intermediate and advanced stages.Finally,the choice for anatomical versus non-anatomical,as well as the role of laparoscopic approach,was overviewed.The literature review suggests that partial hepatectomy for HCC should be considered in the context of multi-disciplinary evaluation of cirrhotic patients.Scientific research on HCC has moved,in recent years,from surgical therapy toward non-surgical approaches and most of the literature regarding topics debated in the present review is represented by observational studies,whereas very few well-designed randomized controlled trials are currently available;thus,no robust recommendations can be derived.展开更多
AIM:To analyze the outcome of hepatocellular car-cinoma(HCC)resection in cirrhosis patients,related to presence of portal hypertension(PH)and extent of hepatectomy.METHODS:A retrospective analysis of 135 patients with...AIM:To analyze the outcome of hepatocellular car-cinoma(HCC)resection in cirrhosis patients,related to presence of portal hypertension(PH)and extent of hepatectomy.METHODS:A retrospective analysis of 135 patients with HCC on a background of cirrhosis was submitted to curative liver resection.RESULTS:PH was present in 44(32.5%)patients.Overall mortality and morbidity were 2.2% and 33.7%,respectively.Median survival time in patients with or without PH was 31.6 and 65.1 mo,respectively(P=0.047);in the subgroup with Child-Pugh class A cirrhosis,median survival was 65.1 mo and 60.5 mo,respectively(P=0.257).Survival for patients submitted to limited liver resection was not significantly different in presence or absence of PH.Conversely,median survival for patients after resection of 2 or more segments with or without PH was 64.4 mo and 163.9 mo,respectively(P=0.035).CONCLUSION:PH is not an absolute contraindication to liver resection in Child-Pugh class A cirrhotic patients,but resection of 2 or more segments should not be recommended in patients with PH.展开更多
Hepatocellular carcinoma(HCC) is the sixth most common type of cancer and the third most frequent cause of cancer-related death. Advances in preoperative assessment of HCC(e.g., imaging studies and liver function test...Hepatocellular carcinoma(HCC) is the sixth most common type of cancer and the third most frequent cause of cancer-related death. Advances in preoperative assessment of HCC(e.g., imaging studies and liver function tests), surgical techniques, and postoperative care have improved the surgical outcomes and survival of patients who undergo hepatic resection for HCC. However, in the last 20 years, the long-term survival after hepatectomy has remained unsatisfactory owing to the high rates of local recurrence and multicentric occurrence. Anatomical liver resection(AR) was introduced in the 1980 s. Although several studies have revealed tangible benefits of AR for HCC, these benefits are still debated. Because most HCCs occur in patients with liver cirrhosis and poor hepatic function, there are many factors that affect survival, including the surgical method. Nevertheless, many studies have documented the perioperative and long-term benefits of AR in various conditions. In this article, we review the results of several recently published, well-designed comparative studies of AR, to investigate whether AR provides real benefits on survival outcomes. We also discuss the potential pitfalls associated with this approach.展开更多
AIM: To evaluate the characters, risks and benefits of laparoscopic cholecystectomy (LC) in cirrhotic portal hypertension (CPH) patients.METHODS: Altogether 80 patients with symptomatic gallbladder disease and CPH, in...AIM: To evaluate the characters, risks and benefits of laparoscopic cholecystectomy (LC) in cirrhotic portal hypertension (CPH) patients.METHODS: Altogether 80 patients with symptomatic gallbladder disease and CPH, including 41 Child class A,32 Child class B and 7 Child class C, were randomly divided into open cholecystectomy (OC) group (38 patients) and LC group (42 patients). The cohorts were well-matched for number, age, sex, Child classification and types of disease.Data of the two groups were collected and analyzed.RESULTS: In LC group, LC was successfully performed in 36 cases, and 2 patients were converted to OC for difficulty in managing bleeding under laparoscope and dense adhesion of Calot's triangle. The rate of conversion was 5.3%. The surgical duration was 62.6±15.2 min. The operative blood loss was 75.5±15.5 mL. The time to resume diet was 18.3±6.5 h. Seven postoperative complications occurred in five patients (13.2%). All patients were dismissed after an average of 4.6±2.4 d. In OC group, the operation time was 60.5±17.5 min. The operative blood loss was 112.5±23.5 mL. The time to resume diet was 44.2±10.5 h.Fifteen postoperative complications occurred in 12patients (30.0%). All patients were dismissed after an average of 7.5±3.5 d. There was no significant difference in operation time between OC and LC group. But LC offered several advantages over OC, including fewer blood loss and lower postoperative complication rate, shorter time to resume diet and shorter length of hospitalization in patients with CPH.CONCLUSION: Though LC for patients with CPH is difficult, it is feasible, relatively safe, and superior to OC.It is important to know the technical characters of the operation, and pay more attention to the meticulous perioperative managements.展开更多
AIM: To examine the hepatitis C virus (HCV) levels and immunological markers in cirrhotic patients after splenectomy. METHODS: HCV RNA titers as well as cellular and humoral immune markers were determined in 20 ci...AIM: To examine the hepatitis C virus (HCV) levels and immunological markers in cirrhotic patients after splenectomy. METHODS: HCV RNA titers as well as cellular and humoral immune markers were determined in 20 cirrhotic patients after splenectomy and in 32 cirrhotic controls with an intact spleen. RESULTS: Serum HCV RNA titers were lower in the splenectomized patients than in the controls (186 ± 225 × 10^3 copies/mL vs 541 ± 417×10^3 copies/mL, P〈0.01). HCV RNA was judged to have been spontaneously eradicated in 4 splenectomized patients, but in none of the controls. Natural killer cell activity was higher in the splenectomized patients than in the controls (41.2 ± 19.3% vs 24.7 ± 15.3%, P〈 0.01), and natural killer cell activity was negatively correlated to HCV RNA titers in the splenectomized patients except in those with serotype 2-related infection. The CEH/CD8 ratio was significantly lower in the splenectomized patients than in the controls. CONCLUSION: The findings suggest that splenectomy may diminish virus burden in cirrhotic patients with HCV infection at least in part, through augmentation of natural killer cell activity.展开更多
AIM: To estimate the contribution of autoimmune thrombocytopenia to hepatitis C virus-related liver cirrhosis (type C cirrhosis), we evaluated the influence of splenectomy upon platelet-associated immunoglobulin G ...AIM: To estimate the contribution of autoimmune thrombocytopenia to hepatitis C virus-related liver cirrhosis (type C cirrhosis), we evaluated the influence of splenectomy upon platelet-associated immunoglobulin G (PAIgG) levels and platelet numbers. METHODS: PAIgG titers and immune markers were determined in 24 type C cirrhotic patients with an intact spleen, 17 type C cirrhotic patients submitted to splenectomy, and 21 non-C cirrhosis with an intact spleen. RESULTS: Thrombocytopenia (PLT〈15×10^4/μL) in type C cirrhosis was diagnosed in all patients with an intact spleen, 8 patients submitted to splenectomy, and in 19 non-C cirrhosis with intact spleen. Elevated titers of PAIgG at more than 25.0 ng/107cells were detected in all cirrhotic patients except for one splenectomized patient. PAIgG titers (ng/10^7cells) were significantly higher in the type C cirrhosis with an intact spleen (247.9 ± 197.0) compared with the splenectomized patients (125.6±87.8) or non-C cirrhosis (152.4± 127.4). PAIgG titers were negatively correlated with platelet counts in type C cirrhotic patients with an intact spleen. In comparison with the type C cirrhosis with an intact spleen, the splenectomized patients had a reduced CD4/CD8 ratio and serum neopterin levels. The spleen index (cm^2) was negatively correlated with platelet counts in the non-C cirrhosis, but not in the type C cirrhosis. CONCLUSION: Our data indicate that the autoimmune mechanism plays an important role in thrombocytosis complicated by HCV-positive cirrhosis. In addition, splenectomy may impair T cells function through, at least in part, a reduction of CD4/CD8 ratio, consequently suppressing PAIgG production.展开更多
The congenital dyserythropoietic anemias comprise a group of rare hereditary disorders of erythropoiesis, characterized by ineffective erythropoiesis as the predominant mechanism of anemia and by characteristic morpho...The congenital dyserythropoietic anemias comprise a group of rare hereditary disorders of erythropoiesis, characterized by ineffective erythropoiesis as the predominant mechanism of anemia and by characteristic morphological aberrations of the majority of erythroblasts in the bone marrow. Congenital dyserythropoietic anemia type II is the most frequent type. All types of congenital dyserythropoietic anemias distinctly share a high incidence of iron loading. Iron accumulation occurs even in untransfused patients and can result in heart failure and liver cirrhosis. We have reported about a patient who presented with liver cirrhosis and intractable ascites caused by congenital dyserythropoietic anemia type II. Her clinical course was further complicated by the development of autoimmune hemolytic anemia. Splenectomy was eventually performed which achieved complete resolution of ascites, increase of hemoglobin concentration and abrogation of transfusion requirements.展开更多
文摘In machining the particle reinforced aluminum based composite material with high Si content using the cobalt-cemented tungsten carbide micro cutting tools, diamond like carbon (DLC) films are deposited on cobalt-cemented tungsten carbide micro-drills with two-step pretreatment method. Characteristics of DLC coated tools are investigated in bias-enhanced HFCVD system with the optimized hot filament arrangement. The optimization deposition technology is obtained and the wear mechanism of cutting tools is analyzed. The drilling performance of DLC coated tools is verified by the experiments of cutting particle reinforced aluminum based composite material (Si 15% in volume) compared with uncoated ones. Experimental results show that the two-step pretreatment method is appropriate for complex shaped cemented carbide substrates and ensures the good adhesive strength between the diamond film and the substrate. The cutting performance of DLC coated tool is enhanced 10 times when machining the Si particle reinforced aluminum based metal matrix composite compared with that of uncoated ones under the same cutting conditions.
文摘A computer aided measurement system is used to measure the cutting temperature directly in high-speed machining by natural thermocouples and standard thermocouples. In this system the tool/workpiece interface temperature is measured by the tool/workpiece natural thermocouple, while the temperature distribution on the workpiece surface and that of interior are measured by some standard thermocouples prearranged at proper positions. The system can be used to measure cutting temperature in the machining with the rotary cutting tools, such as vertical drill and end milling cutter. It is practically used for the research on high-speed milling with hardened steel.
文摘The thrust and the torque of various carbide drills are studied for the high-speed drilling of fiber reinforced epoxy composites. The orthogonal experiment is carried out with different feed speeds at high rotation speed. Experimental results show that the spindle rotation speed is the most influential factor. The thrust andthe torque decrease under the condition of high rotation rate. With the decrease of the feed speed, the thrust and the torque decrease. But the effect of the feed speed is less than that of the spindle rotation rate. Moreover, the effect of drill materials on the thrust and the torque is more notable than that of the drill geometries and the feed speed. The thrust is greatly affected by the feed speed while the torque is obviously affected by drill geometries.
基金Project (201191107) supported by Science and Technology Plan of Xinjiang,China
文摘Target made of 2519-T87 aluminum alloy was obliquely impacted by a projectile. Microstructural evolution around the crater was investigated by optical microscopy (OM), transmission electron microscopy (TEM), and electron backscattered diffraction (EBSD). The micro-hardness distribution near the crater after impact was studied. The results indicate that at the entering stage, the amount of adiabatic shear band (ASB) is the most, and the precipitates are as fine as those of the target material; the micro-hardness is higher than that at the other stages. At the stable-running stage, the amount of ASB reduces as the micro-bands increase; the precipitates tend to coarsen, which leads to the decrease of the micro-hardness. At the leaving stage, there is a large amount of micro-bands; the precipitates are refined, and the micro-hardness is higher than that at the stable-running stage. The difference in the micro-hardness of the impact stages is due to work hardening and precipitate coarsening, which is caused by adiabatic temperature rise in the alloy.
文摘Fatigue cutting is a new approach for separating material. Man-made fatigue can be realized by applying a rotating bending load to a notched bar. To better utilize the new method, laser treatment is adopted in this study. After laser radiation at the notch root, the fatigue cycle of the bar drops dramatically. Based on the experimental result, we draw the conclusion that the fatigue of the bar is influenced by the shape of the hardened area. A hardened area that has a small axial dimension and a relatively large radial dimension facilitates the fatigue. The desirable hardened area can be obtained by controlling the laser treatment parameters.
文摘AIM: To develop a simplified and quick protocol to induce cirrhosis and standardize models of partial liver resection in rats. METHODS: In Fischer F344 rats two modified protocols of phenobarbital-carbon tetrachloride (CCl4) (dilution 50%) gavage to induce cirrhosis (frequency adjusted according to weight, but each subsequent dose was systematically administered) were tested, i.e. the rapid and slow protocols. Prothrombin time (PT) and total bilirubin (TB) were also evaluated. Animals from the rapid group underwent 15% hepatectomy and animals from the slow group underwent 70% hepatectomy. RESULTS: Rapid protocol: This corresponded to 1 gavage/4 d over 6 wk (mortality 30%). Mean PT was 35.2 ±2.8 s (normal: ld.5 s), and mean TB was 1.8 ± 0.2 mg/dL (normal: 0.1 mg/dL). Slow protocol: This cop responded to 1 gavage/6 d over 9 wk (mortality 10%). Mean PT was 11.8 ± 0.2 s (normal: 14.5 s), and mean TB was 0.4 ± 0.04 mg/dL (normal: 0.1 mg/dL). Pathological analyses were performed in both protocols which showed persistent cirrhosis at 3 mo. Rat mortality in the rapid garage group who underwent 15% hepatectomy and in the slow garage group who underwent 70% hepatectomy was 50% and 70%, respectively, CONCLUSION: Our modified model is a simplified method to induce cirrhosis which is rapid (6 to 9 wk), efficient and stable up to 3 mo. Using this method, "Child Pugh A" or "Child Pugh BC" cirrhotic rats were obtained. Our models of cirrhosis and hepatectomy can be used in various situations focusing on postoperative survival.
文摘AIM: To explore the feasibility of performing gastrectomy with D2 lymphadenectomy in gastric cancer patients with liver cirrhosis. METHODS: A total of 7 178 patients were admitted with a diagnosis of liver cirrhosis from January 1993 to December 2003. We reviewed the records of 142 patients who were diagnosed with liver cirrhosis and gastric adenocarcinoma during the same period. Gastrectomy with D2 lymph node dissection for carcinoma of the stomach was performed in 94 patients with histologically proven hepatic cirrhosis. RESULTS: All but 12 patients were dassified as Child's class A. Only 35 patients (37.2%) were diagnosed with cirrhosis before operation. Seventy-three patients underwent a subtotal gastrectomy (77.7%) and 21 patients (22.3%) underwent a total gastrectomy, each with D2 or more lymph node dissection. Two patients (3.8%) who had prophylactic intra-operative drain placement, died of postoperative complications from hepatorenal failure with intractable ascites. Thirty-seven patients (39.4%) experienced postoperative complications. The extent of gastric resection did not influence the morbidity whereas serum aspartate aminotransferase level (P = 0.011) and transfusion did (P = 0.008). The most common postoperative complication was ascites (13.9%) followed by wound infection (10.6%). CONCLUSION: We concluded that the presence of compensated cirrhosis, i.e. Child class A, is not a contraindication against gastrectomy with D2 or more lymph node dissection, when curative resection for gastric cancer is possible. Hepatic reserve and meticulous hemostasis are the likely determinants of operative prognosis.
文摘Hepatocellular carcinoma(HCC) is one of the most frequent neoplasms worldwide and in most cases it is associated with liver cirrhosis.Liver resection is considered the most potentially curative therapy for HCC patients when liver transplantation is not an option or is not immediately accessible.This review is aimed at investigating the current concepts that drive the surgical choice in the treatment of HCC in cirrhotic patients;Eastern and Western perspectives are highlighted.An extensive literature review of the last two decades was performed,on topics covering various aspects of hepatic resection.Early post-operative and long-term outcome measures adopted were firstly analyzed in an attempt to define an optimal standardization useful for research comparison.The need to avoid the development of post-hepatectomy liver failure represents the "conditio sine qua non" of surgical choice and the role of the current tools available for the assessment of liver function reserve were investigated.Results of hepatic resection in relationship with tumor burden were compared with those of available competing strategies,namely,radiofrequency ablation for early stages,and trans-arterial chemoembolization for intermediate and advanced stages.Finally,the choice for anatomical versus non-anatomical,as well as the role of laparoscopic approach,was overviewed.The literature review suggests that partial hepatectomy for HCC should be considered in the context of multi-disciplinary evaluation of cirrhotic patients.Scientific research on HCC has moved,in recent years,from surgical therapy toward non-surgical approaches and most of the literature regarding topics debated in the present review is represented by observational studies,whereas very few well-designed randomized controlled trials are currently available;thus,no robust recommendations can be derived.
文摘AIM:To analyze the outcome of hepatocellular car-cinoma(HCC)resection in cirrhosis patients,related to presence of portal hypertension(PH)and extent of hepatectomy.METHODS:A retrospective analysis of 135 patients with HCC on a background of cirrhosis was submitted to curative liver resection.RESULTS:PH was present in 44(32.5%)patients.Overall mortality and morbidity were 2.2% and 33.7%,respectively.Median survival time in patients with or without PH was 31.6 and 65.1 mo,respectively(P=0.047);in the subgroup with Child-Pugh class A cirrhosis,median survival was 65.1 mo and 60.5 mo,respectively(P=0.257).Survival for patients submitted to limited liver resection was not significantly different in presence or absence of PH.Conversely,median survival for patients after resection of 2 or more segments with or without PH was 64.4 mo and 163.9 mo,respectively(P=0.035).CONCLUSION:PH is not an absolute contraindication to liver resection in Child-Pugh class A cirrhotic patients,but resection of 2 or more segments should not be recommended in patients with PH.
文摘Hepatocellular carcinoma(HCC) is the sixth most common type of cancer and the third most frequent cause of cancer-related death. Advances in preoperative assessment of HCC(e.g., imaging studies and liver function tests), surgical techniques, and postoperative care have improved the surgical outcomes and survival of patients who undergo hepatic resection for HCC. However, in the last 20 years, the long-term survival after hepatectomy has remained unsatisfactory owing to the high rates of local recurrence and multicentric occurrence. Anatomical liver resection(AR) was introduced in the 1980 s. Although several studies have revealed tangible benefits of AR for HCC, these benefits are still debated. Because most HCCs occur in patients with liver cirrhosis and poor hepatic function, there are many factors that affect survival, including the surgical method. Nevertheless, many studies have documented the perioperative and long-term benefits of AR in various conditions. In this article, we review the results of several recently published, well-designed comparative studies of AR, to investigate whether AR provides real benefits on survival outcomes. We also discuss the potential pitfalls associated with this approach.
文摘AIM: To evaluate the characters, risks and benefits of laparoscopic cholecystectomy (LC) in cirrhotic portal hypertension (CPH) patients.METHODS: Altogether 80 patients with symptomatic gallbladder disease and CPH, including 41 Child class A,32 Child class B and 7 Child class C, were randomly divided into open cholecystectomy (OC) group (38 patients) and LC group (42 patients). The cohorts were well-matched for number, age, sex, Child classification and types of disease.Data of the two groups were collected and analyzed.RESULTS: In LC group, LC was successfully performed in 36 cases, and 2 patients were converted to OC for difficulty in managing bleeding under laparoscope and dense adhesion of Calot's triangle. The rate of conversion was 5.3%. The surgical duration was 62.6±15.2 min. The operative blood loss was 75.5±15.5 mL. The time to resume diet was 18.3±6.5 h. Seven postoperative complications occurred in five patients (13.2%). All patients were dismissed after an average of 4.6±2.4 d. In OC group, the operation time was 60.5±17.5 min. The operative blood loss was 112.5±23.5 mL. The time to resume diet was 44.2±10.5 h.Fifteen postoperative complications occurred in 12patients (30.0%). All patients were dismissed after an average of 7.5±3.5 d. There was no significant difference in operation time between OC and LC group. But LC offered several advantages over OC, including fewer blood loss and lower postoperative complication rate, shorter time to resume diet and shorter length of hospitalization in patients with CPH.CONCLUSION: Though LC for patients with CPH is difficult, it is feasible, relatively safe, and superior to OC.It is important to know the technical characters of the operation, and pay more attention to the meticulous perioperative managements.
文摘AIM: To examine the hepatitis C virus (HCV) levels and immunological markers in cirrhotic patients after splenectomy. METHODS: HCV RNA titers as well as cellular and humoral immune markers were determined in 20 cirrhotic patients after splenectomy and in 32 cirrhotic controls with an intact spleen. RESULTS: Serum HCV RNA titers were lower in the splenectomized patients than in the controls (186 ± 225 × 10^3 copies/mL vs 541 ± 417×10^3 copies/mL, P〈0.01). HCV RNA was judged to have been spontaneously eradicated in 4 splenectomized patients, but in none of the controls. Natural killer cell activity was higher in the splenectomized patients than in the controls (41.2 ± 19.3% vs 24.7 ± 15.3%, P〈 0.01), and natural killer cell activity was negatively correlated to HCV RNA titers in the splenectomized patients except in those with serotype 2-related infection. The CEH/CD8 ratio was significantly lower in the splenectomized patients than in the controls. CONCLUSION: The findings suggest that splenectomy may diminish virus burden in cirrhotic patients with HCV infection at least in part, through augmentation of natural killer cell activity.
文摘AIM: To estimate the contribution of autoimmune thrombocytopenia to hepatitis C virus-related liver cirrhosis (type C cirrhosis), we evaluated the influence of splenectomy upon platelet-associated immunoglobulin G (PAIgG) levels and platelet numbers. METHODS: PAIgG titers and immune markers were determined in 24 type C cirrhotic patients with an intact spleen, 17 type C cirrhotic patients submitted to splenectomy, and 21 non-C cirrhosis with an intact spleen. RESULTS: Thrombocytopenia (PLT〈15×10^4/μL) in type C cirrhosis was diagnosed in all patients with an intact spleen, 8 patients submitted to splenectomy, and in 19 non-C cirrhosis with intact spleen. Elevated titers of PAIgG at more than 25.0 ng/107cells were detected in all cirrhotic patients except for one splenectomized patient. PAIgG titers (ng/10^7cells) were significantly higher in the type C cirrhosis with an intact spleen (247.9 ± 197.0) compared with the splenectomized patients (125.6±87.8) or non-C cirrhosis (152.4± 127.4). PAIgG titers were negatively correlated with platelet counts in type C cirrhotic patients with an intact spleen. In comparison with the type C cirrhosis with an intact spleen, the splenectomized patients had a reduced CD4/CD8 ratio and serum neopterin levels. The spleen index (cm^2) was negatively correlated with platelet counts in the non-C cirrhosis, but not in the type C cirrhosis. CONCLUSION: Our data indicate that the autoimmune mechanism plays an important role in thrombocytosis complicated by HCV-positive cirrhosis. In addition, splenectomy may impair T cells function through, at least in part, a reduction of CD4/CD8 ratio, consequently suppressing PAIgG production.
文摘The congenital dyserythropoietic anemias comprise a group of rare hereditary disorders of erythropoiesis, characterized by ineffective erythropoiesis as the predominant mechanism of anemia and by characteristic morphological aberrations of the majority of erythroblasts in the bone marrow. Congenital dyserythropoietic anemia type II is the most frequent type. All types of congenital dyserythropoietic anemias distinctly share a high incidence of iron loading. Iron accumulation occurs even in untransfused patients and can result in heart failure and liver cirrhosis. We have reported about a patient who presented with liver cirrhosis and intractable ascites caused by congenital dyserythropoietic anemia type II. Her clinical course was further complicated by the development of autoimmune hemolytic anemia. Splenectomy was eventually performed which achieved complete resolution of ascites, increase of hemoglobin concentration and abrogation of transfusion requirements.