Background:Since the first success in an adult patient,living donor liver transplantation(LDLT)has become an universally used procedure.Small-for-size syndrome(SFSS)is a well-known complication after partial LT,especi...Background:Since the first success in an adult patient,living donor liver transplantation(LDLT)has become an universally used procedure.Small-for-size syndrome(SFSS)is a well-known complication after partial LT,especially in cases of adult-to-adult LDLT.The definition of SFSS slightly varies among transplant physicians.The use of a partial liver graft has risks of SFSS development.Persistent portal vein(PV)hypertension and PV hyper-perfusion after LT were identified as the main factors.Hence,various approaches were explored to modulate PV flow and decrease PV pressure in order to alleviate this syndrome.Herein,the definition,clinical symptoms,pathophysiology,basic research,as well as preventive and treatment strategies for SFSS are reviewed based on an extensive review of the literature and on our own experiences.Data sources:The articles were collected through PubMed using search terms“liver transplantation”,“living donor liver transplantation”,“living liver donation”,“partial graft”,“small-for-size graft”,“small-forsize syndrome”,“graft volume”,“remnant liver”,“standard liver volume”,“graft to recipient body weight ratio”,“sarcopenia”,“porcine”,“swine”,and“rat”.English publications published before March 31,2020 were included in this review.Results:Many transplant surgeons performed PV flow modulation,including portocaval shunt,splenic artery ligation and splenectomy.With these techniques,patient outcome has been improved even when using a"small"graft.Other factors,such as preoperative recipients’nutritional and skeletal muscle status,graft congestion,and donor factors,were also identified as risk factors which all have been addressed using various strategies.Conclusions:The surgical approach controlling PV flow and pressure could help to prevent SFSS especially in severely ill recipients.In the absence of efficacious medications to resolve SFSS,conservative treatments,including aggressive fluid balance correction for massive ascites,anti-microbiological展开更多
Small-for-size syndrome (SFSS) in adult-to-adult living-related donor liver transplantation (LRLT) remains the greatest limiting factor for the expansion of segmental liver transplantation from either cadaveric or liv...Small-for-size syndrome (SFSS) in adult-to-adult living-related donor liver transplantation (LRLT) remains the greatest limiting factor for the expansion of segmental liver transplantation from either cadaveric or living donors. Portal hyperperfusion, venous pathology, and the arterial buffer response signif icantly contribute to clinical and histopathological manifestations of SFSS. Here, we review the technical aspects of surgical and radiological procedures developed to treat SFSS in LRLT, along with the pathophysiology of this condition.展开更多
Neuroendocrine neoplasms (NENs) of the stomach, duo- denum, appendix or rectum that are small (≤ 1 cm) and well differentiated can be considered "early" tumors, since they generally have a (very) good progn...Neuroendocrine neoplasms (NENs) of the stomach, duo- denum, appendix or rectum that are small (≤ 1 cm) and well differentiated can be considered "early" tumors, since they generally have a (very) good prognosis. In the new WHO classification of 2010, these neoplasms are called neuroendocrine tumors/ carcinoids (NETs), grade (G) 1 or 2, and distinguished from poorly differentiated neuroendocrine carcinomas (NECs), G3. NETs are increasing, with a rise in the age-adjusted incidence in the U.S.A. by about 700 % in the last 35 years. Improved early detection seems to be the main reason for these epidemiological changes. Both the better generalavailability of endoscopy, and imaging techniques, have led to a shift in the discovery of smaller-sized (≤ 10-20 mm) intestinal NETs/carcinoids and earlier tumor stages at diagnosis. Endoscopic screening is therefore effective in the early diagnosis, not only of colorectal adenocarcinomas, but also of NETs/carcinoids. Endoscopic removal, followed up with endoscopic surveillance is the treatment of choice in NETs/carcinoids of the stomach, duodenum and rectum that are ≤ 10 mm in size, have a low proliferative activity (G1), do not infiltrate the muscular layer and show no angioinvasion. In all the other intestinal NENs, optimal treatment generally needs surgery and/or medical therapy depending on type, biology and stage of the tumor, as well as the individual situation of the patient.展开更多
The cover and size distributions of surface rock fragment in hillslopes were investigated by using digital photographing and treating technique in a small catchment in wind-water erosion crisscross region of the Loess...The cover and size distributions of surface rock fragment in hillslopes were investigated by using digital photographing and treating technique in a small catchment in wind-water erosion crisscross region of the Loess Plateau. The results indicated that the maximal cover of rock fragment was pre-sented at mid-position in steep hillslope. Rock fragment presented a general decreasing-trend along the hillslope in gentle hillslope. Rock fragment cover was positively related to gradient, rock fragment size decreased generally along the hillslope, and the size reduced with the gradient. The mean size of rock fragment was at a range of 6―20 mm in the steep hillslope, rock fragment size > 50 mm was rarely presented. The covers of rock fragment at different positions were markedly related to the quantities of rock fragment < 40 mm. The area of rock fragment of 2―50 mm accounted for 60% or more of the total area, dominating the distribution of rock fragment in the hillslopes.展开更多
文摘Background:Since the first success in an adult patient,living donor liver transplantation(LDLT)has become an universally used procedure.Small-for-size syndrome(SFSS)is a well-known complication after partial LT,especially in cases of adult-to-adult LDLT.The definition of SFSS slightly varies among transplant physicians.The use of a partial liver graft has risks of SFSS development.Persistent portal vein(PV)hypertension and PV hyper-perfusion after LT were identified as the main factors.Hence,various approaches were explored to modulate PV flow and decrease PV pressure in order to alleviate this syndrome.Herein,the definition,clinical symptoms,pathophysiology,basic research,as well as preventive and treatment strategies for SFSS are reviewed based on an extensive review of the literature and on our own experiences.Data sources:The articles were collected through PubMed using search terms“liver transplantation”,“living donor liver transplantation”,“living liver donation”,“partial graft”,“small-for-size graft”,“small-forsize syndrome”,“graft volume”,“remnant liver”,“standard liver volume”,“graft to recipient body weight ratio”,“sarcopenia”,“porcine”,“swine”,and“rat”.English publications published before March 31,2020 were included in this review.Results:Many transplant surgeons performed PV flow modulation,including portocaval shunt,splenic artery ligation and splenectomy.With these techniques,patient outcome has been improved even when using a"small"graft.Other factors,such as preoperative recipients’nutritional and skeletal muscle status,graft congestion,and donor factors,were also identified as risk factors which all have been addressed using various strategies.Conclusions:The surgical approach controlling PV flow and pressure could help to prevent SFSS especially in severely ill recipients.In the absence of efficacious medications to resolve SFSS,conservative treatments,including aggressive fluid balance correction for massive ascites,anti-microbiological
文摘Small-for-size syndrome (SFSS) in adult-to-adult living-related donor liver transplantation (LRLT) remains the greatest limiting factor for the expansion of segmental liver transplantation from either cadaveric or living donors. Portal hyperperfusion, venous pathology, and the arterial buffer response signif icantly contribute to clinical and histopathological manifestations of SFSS. Here, we review the technical aspects of surgical and radiological procedures developed to treat SFSS in LRLT, along with the pathophysiology of this condition.
文摘Neuroendocrine neoplasms (NENs) of the stomach, duo- denum, appendix or rectum that are small (≤ 1 cm) and well differentiated can be considered "early" tumors, since they generally have a (very) good prognosis. In the new WHO classification of 2010, these neoplasms are called neuroendocrine tumors/ carcinoids (NETs), grade (G) 1 or 2, and distinguished from poorly differentiated neuroendocrine carcinomas (NECs), G3. NETs are increasing, with a rise in the age-adjusted incidence in the U.S.A. by about 700 % in the last 35 years. Improved early detection seems to be the main reason for these epidemiological changes. Both the better generalavailability of endoscopy, and imaging techniques, have led to a shift in the discovery of smaller-sized (≤ 10-20 mm) intestinal NETs/carcinoids and earlier tumor stages at diagnosis. Endoscopic screening is therefore effective in the early diagnosis, not only of colorectal adenocarcinomas, but also of NETs/carcinoids. Endoscopic removal, followed up with endoscopic surveillance is the treatment of choice in NETs/carcinoids of the stomach, duodenum and rectum that are ≤ 10 mm in size, have a low proliferative activity (G1), do not infiltrate the muscular layer and show no angioinvasion. In all the other intestinal NENs, optimal treatment generally needs surgery and/or medical therapy depending on type, biology and stage of the tumor, as well as the individual situation of the patient.
基金the Program for Innovative Research Team in University (Grant No. IRT0749)the National Natural Science Foundation of China (Grant No. 50479063)
文摘The cover and size distributions of surface rock fragment in hillslopes were investigated by using digital photographing and treating technique in a small catchment in wind-water erosion crisscross region of the Loess Plateau. The results indicated that the maximal cover of rock fragment was pre-sented at mid-position in steep hillslope. Rock fragment presented a general decreasing-trend along the hillslope in gentle hillslope. Rock fragment cover was positively related to gradient, rock fragment size decreased generally along the hillslope, and the size reduced with the gradient. The mean size of rock fragment was at a range of 6―20 mm in the steep hillslope, rock fragment size > 50 mm was rarely presented. The covers of rock fragment at different positions were markedly related to the quantities of rock fragment < 40 mm. The area of rock fragment of 2―50 mm accounted for 60% or more of the total area, dominating the distribution of rock fragment in the hillslopes.
