Live donor liver transplantation in adults: graft size, related anatomical anomaly and imaging evaluation of donor

The shortage of cadaveric livers has sparked aninterest in adult live donor liver transplantation. Rightlobe donor hepatectomy is frequently required to ob-tain a graft of adequate size for adult recipients. Thisprocedure requires not only a precise understanding ofliver anatomy and anatomic anomaly, but also themeans of assessing them. This review focuses on thekey points in adult live donor liver transplantation us-ing the right lobe combined with our own experiencein 81 cases including graft size, related anatomicalanomaly and imaging evaluation of donor.

Impact of small-for-size liver grafts on medium-term and long-term graft survival in living donor liver transplantation: A meta-analysis

BACKGROUND Small-for-size grafts (SFSGs) in living donor liver transplantation (LDLT) could optimize donor postoperative outcomes and also expand the potential donor pool. Evidence on whether SFSGs would affect medium-term and long-term recipient graft survival is lacking. AIM To evaluate the impact of small-for-size liver grafts on medium-term and longterm graft survival in adult to adult LDLT. METHODS A systematic review and meta-analysis were performed by searching eligible studies published before January 24, 2019 on PubMed, EMBASE, and Web of Science databases. The primary outcomes were 3-year and 5-year graft survival. Incidence of small-for-size syndrome and short term mortality were also extracted. RESULTS This meta-analysis is reported according to the guidelines of the PRISMA 2009 Statement. Seven retrospective observational studies with a total of 1821 LDLT recipients were included in the meta-analysis. SFSG is associated with significantly poorer medium-term graft survival. The pooled odds ratio for 3-year graft survival was 1.58 [95% confidence interval 1.10-2.29, P = 0.014]. On the other hand, pooled results of the studies showed that SFSG had no significant discriminatory effect on 5-year graft survival with an odds ratio of 1.31 (95% confidence interval 0.87-1.97, P = 0.199). Furthermore, incidence of small-for-size syndrome detected in recipients of SFSG ranged from 0-11.4% in the included studies. CONCLUSION SFSG is associated with inferior medium-term but not long-term graft survival. Comparable long-term graft survival based on liver graft size shows that smaller grafts could be accepted for LDLT with appropriate flow modulatory measures. Close follow-up for graft function is warranted within 3 years after liver transplantation.

Outcome of patients undergoing right lobe living donor liver transplantation with small-for-size grafts

AIM:To investigate the outcome of living donor liver transplantation(LDLT)recipients transplanted with small-for-size grafts(SFSGs).METHODS:Between November 2001 and December2010,196 patients underwent LDLT with right lobe liver grafts at our center.Recipients were divided into 2 treatment groups:group A with an actuarial graft-to-recipient weight ratio(aGRWR)<0.8%(n=45)and group B with an aGRWR≥0.8%(n=151).We evaluated serum liver function markers within 4 wk after transplantation.We also retrospectively evaluated the outcomes of these patients for potential effects related to the recipients,the donors and the transplantation procedures based upon a review of their medical records.RESULTS:Small-for-size syndrome(SFSS)developed in 7 of 45 patients(15.56%)in group A and 9 of 151patients(5.96%)in group B(P=0.080).The levels of alanine aminotransferase and aspartate aminotransferase in group A were higher than those in group B during early period after transplantation,albeit not significantly.The cumulative 1-,3-and 5-year liver graft survival rates were 82.22%,71.11%and 71.11%for group A and 81.46%,76.82%,and 75.50%for group B patients,respectively(P=0.623).However,univariate analysis of risk factors associated with graft survival in group A demonstrated that the occurrence of SFSS after LDLT was the only significant risk factor affecting graft survival(P<0.001).Furthermore,multivariate analysis of our data did not identify any additional significant risk factors accounting for poor graft survival.CONCLUSION:Our study suggests that LDLT recipients with an aGRWR<0.8%may have liver graft outcomes comparable to those who received larger size grafts.Further studies are required to ascertain the safety of using SFSGs.

Tacrolimus dosage requirements in living donor liver transplant recipients with small-for-size grafts

AIM:To investigate the tacrolimus dosage requirements and blood concentrations in adult-to-adult right lobe living donor liver transplantation (AALDLT) recipients with small-for-size (SFS) grafts.METHODS: During January 2007 and October 2008, a total of 54 cases of AALDLT with an observation period of 6 mo were enrolled in this study. The 54 patients were divided into two groups according to graft-recipient body weight ratio (GRBW): SFS grafts group (Group S, GRBW<0.8%, n=8) and non-SFS grafts group (Group N, GRBW ≥0.8%, n=46). Tacrolimus 12-hour blood levels and doses were recorded during weeks 1,2,3 and 4 and months 2,3,4,5 and 6 in group S and group N. Meanwhile, acute rejection rates, liver and renal function test results, and the number of potentially interacting medications were determined at each interval in the two groups. A comparison of tacrolimus dosage requirements and blood levels were made weekly in the first month post-surgery, and monthly from months 2 to 6.RESULTS: There were no differences in the demo-graphic characteristics, acute rejection rates, liver and renal function test results, or the number of potentially interacting medications administered between the two groups. The tacrolimus dosage requirements in group S were significantly lower than group N at 2 wk (2.8±0.4 mg/d vs 3.6±0.7 mg/d, P=0.006), 3 wk (2.9±0.7 mg/d vs 3.9±0.8 mg/d, P=0.008), 4 wk (2.9±0.8 mg/d vs 3.9±1.0 mg/d, P=0.023) and 2 mo (2.8±0.7 mg/d vs 3.8 ±1.1 mg/d, P=0.033). Tacrolimus 12-h trough concentrations were similar between the two groups at all times except for 2 wk post-transplantation, when the concentrations were signifi cantly greater in group S recipients than in group N recipients (11.3±4.8 ng/mL vs 7.0±3.8 ng/mL, P=0.026).CONCLUSION: SFS grafts recipients have signifi cantly decreased tacrolimus dosage requirements compared with non-SFS grafts recipients in AALDLT during the first 2 mo post-surgery.

Outcomes of adult patients adopting small-for-size grafts in living donor liver transplantation: A systematic review and meta-analysis

Background: Small-for-size graft(SFSG) has emerged as one of the very contentions in adult-to-adult living donor liver transplantation(LDLT) as a certain graft size is related to recipients’ prognosis. Graftto-recipient weight ratio(GRWR)≥0.8% was considered as a threshold to conduct LDLT. However, this also has been challenged over decades as a result of technique refinements. For a better understanding of SFSG in practice, we conducted this meta-analysis to compare the perioperative outcomes and long-term outcomes between patients adopting the grafts with a lower volume(GRWR < 0.8%, SFSG group) and sufficient volume(GRWR ≥ 0.8%, non-SFSG group) in adult-to-adult LDLT. Data sources: The studies comparing recipients adopting graft with a GRWR < 0.8% and ≥ 0.8% were searched by three authors independently in Pub Med, Web of Science, Embase, the Cochrane Library, MEDLINE and Google Scholar databases until September 2018 and data were analyzed by RevMan 5.3.5. Results: Sixteen studies with a total of 3272 subjects were included in this meta-analysis. In terms of small-for-size syndrome(SFSS), no significant difference was found in subjects enrolled after year 2010(before 2010, OR = 3.00, 95% CI: 1.69–5.35, P = 0.0002;after 2010, OR = 1.23, 95% CI: 0.79–1.90, P = 0.36;P for interaction: 0.02). There was no significant difference in operative duration, blood loss, cold ischemia time, biliary complications, acute rejection, postoperative bleeding, hospitalization time, perioperative mortality, and 1-, 3-and 5-year overall survival rates between two groups. Conclusions: This meta-analysis suggested that adopting SFSG in adult LDLT has comparable outcomes to those with non-SFSG counterparts since 2010.

Outcomes of right-lobe and left-lobe living-donor liver transplantations using small-for-size grafts

AIM To analyze the outcomes of living-donor liver transplantation(LDLT) using left-lobe(LL) or right-lobe(RL) small-for-size(SFS) grafts.METHODS Prospectively collected data of adult patients who underwent LDLT at our hospital in the period from January 2003 to December 2013 were reviewed. The patients were divided into the RL-LDLT group and the LL-LDLT group. The two groups were compared in terms of short-and long-term outcomes, including incidence of postoperative complication, graft function, graft survival, and patient survival. A SFS graft was defined as a graft with a ratio of graft weight(GW) to recipient standard liver volume(RSLV)(GW/RSLV) of < 50%. The Urata formula was used to estimate RSLV.RESULTS Totally 218 patients were included for analysis, with 199 patients in the RL-LDLT group and 19 patients in the LL-LDLT group. The two groups were similar in terms of age(median, 53 years in the RL-LDLT group and 52 years in the LL-LDLT group, P = 0.997) but had significantly different ratios of men to women(165:34 in the RL-LDLT group and 8:11 in the LL-LDLT group, P < 0.0001). The two groups were also significantly different in GW(P < 0.0001), GW/RSLV(P < 0.0001), and graft cold ischemic time(P = 0.007). When it comes to postoperative complication, the groups were comparable(P = 0.105). Five patients died in hospital,4(2%) in the RL-LDLT group and 1(5.3%) in the LLLDLT group(P = 0.918). There were 38 graft losses, 33(16.6%) in the RL-LDLT group and 5(26.3%) in the LL-LDLT group(P = 0.452). The 5-year graft survival rate was significantly better in the RL-LDLT group(95.2% vs 89.5%, P = 0.049). The two groups had similar 5-year patient survival rates(RL-LDLT: 86.8%, LL-LDLT: 89.5%, P = 0.476).CONCLUSION The use of SFS graft in LDLT requires careful tailormade surgical planning and meticulous operation. LLLDLT can be a good alternative to RL-LDLT with similar recipient outcomes but a lower donor risk. Further research into different patient conditions is needed in order to validate the use of LL graft.

Role of “reduced-size” liver/bowel grafts in the “abdominal wall transplantation” era

The evolution of multi-visceral and isolated intestinal transplant techniques over the last 3 decades has highlighted the technical challenges related to the closure of the abdomen at the end of the procedure.Two key factors that contribute to this challenge include:(1) Volume/edema of donor graft;and(2) loss of abdominal domain in the recipient.Not being able to close the abdominal wall leads to a variety of complications and morbidity that range from complex ventral hernias to bowel perforation.At the end of the 90's this challenge was overcome by graft reduction during the donor operation or bench table procedure(especially reducing liver and small intestine),as well as techniques to increase the volume of abdominal cavity by pre-operative expansion devices.Recent reports from a few groups have demonstrated the ability of transplanting a full-thickness,vascularized abdominal wall from the same donor.Thus,a spectrum of techniques have co-evolved with multivisceral and intestinal transplantation,ranging from graft reduction to enlarging the volume of the abdominal cavity.None of these techniques are free from complications,however in large-volume centers the combinations of both(graft reduction and abdominal widening,sometimes used in the same patient) could decrease the adverse events related to recipient's closure,allowing a faster recovery.The quest for a solution to this unique challenge has led to the proposal and implementation of innovative solutions to enlarge the abdominal cavity.

Healing Mechanism and Osteogenic Capacity of Bovine Bone Mineral—Human Amniotic Mesenchymal Stem Celland Autogenous Bone Graft in Critical Size Mandibular Defect

Experiments on maxillofacial bone tissue engineering showed the promising result;however, its healing mechanisms and effectiveness had not been fully understood. The aim of this study is to compare the bone healing mechanism and osteogenic capacity between bovine bone mineral loaded with hAMSC and autogenous bone graft in the reconstruction of critical size mandibular bone defect. Critical size defects were made at the mandible of 45 New Zealand white rabbits reconstructed with BBM-hAMSC, BBM alone, and ABG, respectively. At the end of first, second, and twelfth weeks, five rabbits from each experimental week were sacrificed for histology and immunohistochemistry staining. Expressions of vascular endothelial growth factor (VEGF), bone mor-phogenic proteins-2 (BMP2), Runx2 and the amount of angiogenesis were analyzed in the first and second week groups, while expressions of Runx2, osteocalcin, collagen type-I fibres, trabecular area and bone incorporation were analyzed in the twelfth week groups. The result showed that expressions of VEGF, BMP2 and Runx2 as well as the amount of angiogenesis were higher in ABG compared with BBM-hAMSC group in the first and second weeks of healing. The result of twelfth week of healing showed that expressions of Runx2 and osteocalcin as well as the thickness of collagen type-I fibres were significantly higher in BBM-hAMSC compared to ABG group, while there was no statistically difference in trabecular area and bone incorporation between BBM-hAMSC and ABG group. This study concluded that early healing activities were higher in auto-genous bone graft than in BBM-hAMSC, while osteogenic activities in the late stage of healing were higher in BBM-hAMSC compared to autogenous bone graft. It was also concluded that the osteo-genic capacity of BBM-hAMSC was comparable to autogenous bone graft in the reconstruction of critical size defect in the mandible.

Graft-to-recipient weight ratio lower to 0.7% is safe without portal pressure modulation in right-lobe living donor liver transplantation with favorable conditions

BACKGROUND: The low graft-to-recipient weight ratio(GRWR) in adult-to-adult living donor liver transplantation(LDLT) is one of the major risk factors affecting graft survival. The goal of this study was to evaluate whether the lower limit of the GRWR can be safely reduced without portal pressure modulation in right-lobe LDLT. METHODS: From 2005 to 2011, 317 consecutive patients from a single institute underwent LDLT with right-lobe grafts without portal pressure modulation. Of these, 23 had a GRWR of less than 0.7%(group A), 27 had a GRWR of ≥0.7%, 【0.8%(group B), and 267 had a GRWR of more than and equal to 0.8%(group C). Medical records, including recipient, donor, operation factors, laboratory findings and complications were reviewed retrospectively. RESULTS: The baseline demographics showed low model for end-stage liver disease score(mean 16.3±8.9) and high percentage of hepatocellular carcinoma(231 patients, 72.9%). Three groups by GRWR demonstrated similar characteristics except recipient body mass index and donor gender. For smallforsize syndrome, there were 3(13.0%) in group A, 1(3.7%) in group B, and 2 patients(0.7%) in group C(P【0.001). Hepatic artery thrombosis was more frequently observed in group A than in groups B and C(8.7% vs 3.7% vs 1.9%, P=0.047). However, among the three groups, graft survival rates at 1 year(100% vs 96.3% vs 93.6%) and 3 years(91.7% vs 73.2% vs 88.1%) were not different(P=0.539). In laboratory measurements,there was no group difference in total bilirubin and albumin. However, prothrombin time was longer in group A within postoperative 1 week and platelet count was lower in groups A and B within postoperative 1 month. CONCLUSION: A GRWR lower to 0.7% is safe and does not need to modulate portal pressure in adult-to-adult LDLT using the right-lobe in favorable conditions including low model for end-stage liver disease score.

SYNTHESIS AND SIZING PROPERTIES OF GRAFT STARCHES AS WARP SIZING MATERIALS FOR POLYESTER/COTTON BLEND SPUN YARN

Grafting a number of monomers such as acrylic acid, acrylamide, methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, butyl methacrylate and vinyl acetate onto granular corn starch was carried out respectively in aqueous dispersion by using cerie ammonium nitrate as an initiator under nitrogen atmosphere. Conversion of monomer, grafting ratio and grafting efficiency were measured by the method of combining the chemical quantitative analysis with the weight. The adhesive power of the starch graft copolymers to polyester/cotton fiber was evaluated by measuring the breaking strength and elongation of the roving impregnated with the paste. The viscosity change of the size paste before and after grafting was studied. The mechanical properties of polyester/cotton fibre yarn sized by the graft starch were tested. The main conclusions are as follows: (1) monomers which were graft coplymerized onto starch have a significant influence upon the viscosity of the size paste; (2) the adhesive power

Small for size syndrome difficult dilemma: Lessons from 10 years single centre experience in living donor liver transplantation

AIM To analyze the incidence, risk factors, prevention, treatment and outcome of small for size syndrome(SFSS) after living donor liver transplantation(LDLT). METHODS Through-out more than 10 years: During the period from April 2003 to the end of 2013, 174 adult-to-adults LDLT(A-ALDLT) had been performed at National Liver Institute, Menoufiya University, Shibin Elkoom, Egypt. We collected the data of those patients to do this cohort study that is a single-institution retrospective analysis of a prospectively collected database analyzing the incidence, risk factors, prevention, treatment and outcome of SFSS in a period started from the end of 2013 to the end of 2015. The median period of follow-up reached 40.50 m, range(0-144 m). RESULTS SFSS was diagnosed in 20(11.5%) of our recipients. While extra-small graft [small for size graft(SFSG)], portal hypertension, steatosis and left lobe graft were significant predictors of SFSS in univariate analysis(P = 0.00, 0.04, 0.03, and 0.00 respectively); graft size was the only independent predictor of SFSS on multivariate analysis(P = 0.03). On the other hand, there was lower incidence of SFSS in patients with SFSG who underwent splenectomy [4/10(40%) SFSS vs 3/7(42.9%) no SFSS] but without statistical significance, However, there was none significant lower incidence of the syndrome in patients with right lobe(RL) graft when drainage of the right anterior and/or posterior liver sectors by middle hepatic vein, V5, V8, and/or right inferior vein was done [4/10(28.6%) SFSS vs 52/152(34.2%) no SFSS]. The 6-mo, 1-, 3-, 5-, 7-and 10-year survival in patients with SFSS were 30%, 30%, 25%, 25%, 25% and 25% respectively, while, the 6-mo, 1-, 3-, 5-, 7-and 10-year survival in patients without SFSS were 70.1%, 65.6%, 61.7%, 61%, 59.7%, and 59.7% respectively, with statistical significant difference(P = 0.00). CONCLUSION SFSG is the independent and main factor for occurrence of SFSS after A-ALDLT leading to poor outcome. However, the management of this catastrophe depends upon its prevention(i.e., selecting graft with proper size, splenectomy to decrease portal venous inflow, and improving hepatic vein outflow by reconstructing large draining veins of the graft).

THE ADHESIVE CAPACITY OF STARCH GRAFT COPOLYMERS TO POLYESTER/COTTON FIBER

The advantages of using starch graft copolymers as warp sizes in textile were briefly discussed, and the factors of affecting adhesive capacity to the fiber were analysed. By using eerie ammonium nitrate as an initiator under nitrogen atomosphere, a number of vinyl and/or acrylic monomers such as acrylic acid, acrylamide, methyl acrylate, ethyl acrylate, butyl acrylate, hydroxyethyl acrylate, methyl methacrylate, butyl methacrylate, vinyl acetate and the combinations among them were graft copolymerized respectively onto granular corn starch in aqueous dispersion. The adhesive capacity of these starch graft copolymers to polyester/cotton fibers was evaluated by a slightly sized rovings according to V. K. Aggarwal’s method which measures the breaking strength and elongation of the rovings impregnated with the size paste. The influences of the monomers and their combinations, the grafting technological processes and the pretreatment methods before graft copolymerization upon adhesive capacity have been

Expression of iNOS in early injury in a rat model of small-for-size liver transplantation

BACKGROUND: Living donor liver transplantation has been widely accepted as the treatment of choice for end-stage liver disease. Large amounts of nitric oxide generated by inducible nitric oxide synthase (iNOS) have been shown to play an important role in many inflammatory and immune reactions, but expression of iNOS in small-for-size liver transplantation is unknown. The aims of this study were to determine the time course of iNOS mRNA and protein as well as the redox state of liver biopsies in a rat model of small-for-size liver transplantation. METHODS: Male Sprague-Dawley rats were divided into a control group, a warm ischemia-reperfusion (IR) group, and a small-for-size liver graft group. Real-time RT-PCR and Western blotting were used to characterize the time course of the expression of iNOS mRNA and protein, respectively. Malondialdehyde (MDA) and superoxide dismutase (SOD) were used as markers to characterize the redox state of liver tissues, and the time courses of MDA and SOD levels were also measured. RESULTS: The expression of iNOS mRNA and protein levels in the warm IR and small-for-size graft groups both significantly increased after reperfusion, and peaked at 3 hours. Moreover, the increase in MDA was accompanied by increased iNOS in the period of 1-24 hours after reperfusion. The MDA levels in the warm IR and small-for-size graft groups significantly increased after reperfusion, peaked at 3 hours, and decreased thereafter. The direction of change in SOD was opposite that of the change in MDA. CONCLUSIONS: The expression of iNOS mRNA and protein is activated after reperfusion both in hepatic warm IR injury and small-for-size liver graft. Furthermore, the results of this study suggest that iNOS contributes to the damage in warm IR injury and small-for-size grafts via free oxygen radicals.

Early graft dysfunction following adult-to-adult livingrelated liver transplantation:Predictive factors and outcomes

AIM:To describe a condition that we define as early graft dysfunction(EGD)which can be identified preoperatively. METHODS:Small-for-size graft dysfunction following living-related liver transplantation(LRLT)is characterized by EGD when the graft-to-recipient body weight ratio(GRBWR)is below 0.8%.However, patients transplanted with GRBWR above 0.8%can develop dysfunction of the graft.In 73 recipients of LRLT(GRBWR>0.8%),we identified 10 patients who developed EGD.The main measures of outcomes analyzed were overall mortality,number of re-transplants and length of stay in days(LOS).Furthermore we analyzed other clinical pre-transplant variables,intraoperative parameters and post transplant data.RESULTS:A trend in favor of the non-EGD group(3-mo actuarial survival 98%vs 88%,P=0.09;3-mo graft mortality 4.7%vs 20%,P=0.07)was observed as well as shorter LOS(13 d vs 41.5 d;P=0.001)and smaller requirement of peri-operative Units of Plasma (4 vs 14;P=0.036).Univariate analysis of pre- transplant variables identified platelet count,serum bilirubin,INR and Meld-Na score as predictors of EGD. In the multivariate analysis transplant Meld-Na score (P=0.025,OR:1.175)and pretransplant platelet count(P=0.043,OR:0.956)were independently associated with EGD. CONCLUSION:EGD can be identified preoperatively and is associated with increased morbidity after LRLT. A prompt recognition of EGD can trigger a timely treatment.

Research on the Sizing Performance of Starch Grafted Poly-hydroxy Alkyl-acid Esters

Starch grafted poly-hydroxy alkyl-acid esters were prepared via graft polymerization.Different characteristics of grafted starches were tested such as viscosity,viscosity stability,adhesion as well as properties of sized yarns.Sizing performance was analyzed from the aspect of physical and chemical reactions between polymer molecules.It shows that starch grafted poly-hydroxy alkyl-acid esters have excellent sizing performance and could absolutely be used as sizes for polyester-cotton yarns.

含双键单体接枝改性角蛋白浆料制备及性能

角蛋白浆料作为一类新型环保纺织浆料具有广阔应用前景,然而角蛋白浆料上浆纱线在烘干后易出现浆膜脆裂的问题。文中通过化学改性法制备接枝改性角蛋白浆料,在角蛋白主链上引入与被浆纱线结构相似的柔性支链,改善浆膜的强力、柔韧性,同时提高浆膜对纱线的黏附性。制备出一系列乙烯基单体改性角蛋白浆料。结果表明,改性角蛋白制备条件:在20℃的条件下,接枝单体为甲基丙烯酸甲酯时,单体用量为100%,引发剂用量为3%,接枝体系pH值为7,接枝2 h;在20℃的条件下,接枝单体为衣康酸时,单体用量为60%,引发剂用量为3%,接枝体系pH值为7,接枝1 h。在上述两种条件下的浆膜力学性能最佳;浆料的黏附性、浆纱的拉伸性能、耐磨性能及毛羽降低率均增强。

砧木规格对‘八重寒绯樱’嫁接苗生长的影响

以钟花樱为砧木嫁接‘八重寒绯樱’,探究砧木地径规格对嫁接苗的成活率、接口愈合、株高及接口径的影响。结果表明:小规格(6~9 mm)砧木嫁接‘八重寒绯樱’时嫁接苗成活和接口愈合情况最好,嫁接成活率为83.33%,全愈率为80%,3种规格砧木的愈合良好率均达90%以上;砧木越粗时,嫁接苗的生长量越大,其中大规格(16~20 mm)砧木的嫁接苗株高和接口径分别为311.47 cm和16.56 mm;‘八重寒绯樱’嫁接苗速生期生长量占总生长量的57.74%~58.04%,株高和接口径速生期持续时间、接口径速生期生长量均与砧木大小呈正比,株高速生期生长量以中规格(10~15 mm)和大规格砧木的较高。

云南核桃主要栽培品种的嫁接技术研究

核桃植株酚类物质含量高、易氧化,导致嫁接成活率低,成为影响良种繁育推广的一个难题。开展影响核桃嫁接成活率诸因子及作用的研究,对提高核桃嫁接成活率、推广优良新品种具有重要意义。以云南省3个主要核桃栽培品种漾濞泡核桃、云新高原、娘青核桃为试验材料,研究不同嫁接砧木和不同接穗对苗木成活率及其生长节律的影响。结果表明:1)采用1年生铁核桃苗作砧木和采用芽苗作砧木对各品种嫁接成活率存在较大影响,用芽苗砧嫁接的漾濞泡核桃、娘青核桃的成活率明显高于用1年生铁核桃砧嫁接的。2)3个核桃品种选用不同砧木嫁接后,苗高、地径生长都符合“S”型生长曲线。3)3个核桃品种选用不同砧木嫁接成活后,生长态势存在明显差异,用1年生铁核桃砧嫁接的漾濞泡核桃、娘青核桃后期苗高、地径生长量均高于用芽苗砧嫁接的生长量。4)用漾濞泡核桃顶芽和侧芽进行芽苗砧嫁接试验显示,侧芽嫁接出圃率远大于顶芽嫁接出圃率,侧芽嫁接的苗木长势明显优于顶芽嫁接。

微波场中土豆淀粉丙烯酸接枝浆料的制备及性能

在微波场中实现土豆淀粉与丙烯酸的接枝共聚 ,可制备土豆接枝淀粉。对接枝共聚物用红外光谱进行了表征 ,采用粗纱法研究了土豆淀粉 丙烯酸接枝浆料对棉与涤棉混纺纱的粘着性能。

亚固相条件下接枝淀粉的制备与性能

在亚固相条件下制备淀粉-丙烯酸丁酯接枝淀粉,并进行性能测试。利用淀粉大分子的结构特点,对玉米淀粉与丙烯酸类单体在亚固相条件下进行接枝共聚,分析了引发剂的用量、单体的用量、反应时间、反应温度、亚固相程度等因素对淀粉接枝共聚反应的影响。扫描电镜和红外光谱试验表明玉米淀粉与丙烯酸丁酯实现了接枝共聚。对所研制的接枝淀粉浆料性能进行测试,结果表明该浆料性能好于磷酸酯淀粉,适用于涤棉混纺纱上浆。