Changes in concentrations and transcripts of plant hormones in wheat seedling roots in response to Fusarium crown rot

Fusarium crown rot(FCR) is a soilborne disease causing severe yield losses in many wheat-growing areas of the world. Diseased plants show browning and necrosis of roots and stems causing white heads at maturity. Little is known about the molecular processes employed by wheat roots to respond to the disease. We characterized morphological, transcriptional and hormonal changes in wheat seedling roots following challenge with Fusarium pseudograminearum(Fp), the main pathogen of FCR. The pathogen inhibited root development to various extents depending on plants' resistance level. Many genes responsive to FCR infection in wheat roots were enriched in plant hormone pathways. The contents of compounds involved in biosynthesis and metabolism of jasmonic acid, salicylic acid, cytokinin and auxin were drastically changed in roots at five days post-inoculation. Presoaking seeds in methyl jasmonate for 24 h promoted FCR resistance, whereas presoaking with cytokinin 6-benzylaminopurine made plants more susceptible. Overexpression of TaOPR3, a gene involved in jasmonic acid biosynthesis, enhanced plant resistance as well as root and shoot growth during infection.

Residual Fatigue Life Prediction of Ball Bearings Based on Paris Law and RMS

Paris law can reflect the failure mechanism of materials and is usually used to be a method to predict fatigue life or residual fatigue life.But the variable which can represent the health of machine is hardly measured on line.To a degree,the difficulty of on-line application restricts the scope of application of Paris law.The relationship between characteristic values of vibration signals and the variable in the Paris equation which can describe the health of machine is investigated by taking ball bearings as investigative objects.Based on 6205 deep groove ball bearings as a living example,historical lives and vibration signals are analyzed.The feasibility of describing that variable in the Paris equation by the characteristic value of vibration signals is inspected.After that vibration signals decomposed by empirical mode decomposition（EMD）,root mean square（RMS） of intrinsic mode function（IMF） involving fault characteristic frequency has a consistent trend with the diameter of flaws.Based on the trend,two improved Paris models are proposed and the scope of application of them is inspected.These two Paris Models are validated by fatigue residual life data from tests of rolling element bearings and vibration signals monitored in the process of operation of rolling element bearings.It shows that the first improved Paris Model is simple and plain and it can be easily applied in actual conditions.The trend of the fatigue residual life predicted by the second improved Paris model is close to the actual conditions and the result of the prediction is slightly greater than the truth.In conclusion,after the appearance of detectable faults,these improved models based on RMS can predict residual fatigue life on line and a new approach to predict residual fatigue life of ball bearings on line without disturbing the machine running is provided.

Genetic Diversity of Fusarium solani f. sp. cucurbitae, the Causal Root and Crown Rot of Cucurbits (Melon) by Using Molecular Markers and Control

Detection of F. solani f. sp. cucurbitae causal agent of the crown and root rot disease of melon race 1, race 2 is difficult. It is based only on morphological characteristic. In this study, forty isolates identified as Fusarium solani based on morphological characterization, F. solani was one of the most frequently isolated species. Molecular identification of these isolates by PCR technique using species-specific primer, indicated that thirty-two isolates, amplified product 580 bp (race 1) and two isolate amplified product 580 bp (race 2), while six isolates were not amplified with primer of both races. Production of Trichothecenes (T2-toxen, DON.) by Fusarium solani was conducted on isolates confirmed as belonging in the F. solani by PCR. The results indicated that the presence of Tri5, Tri13 genes is coding the ability of synthesis mycotoxin. In vitro, the results indicated that NPs (AgNPs, MgNPs) and chemical (Phylex) possess the antifungal properties against at various level. Treatment with (AgNPs 150 ppm, MgNPs 2%, 3% ppm) and 3% Phylex resulted in maximum inhabitation of F. solani . In vivo, five characters (height plant, hoot ant root fresh and dry weight) were measured based on the greenhouse, field experimental results. Treatment with (AgNPs, MgNPs) and Phylex had higher measured parameters than positive control.

Effects of Two Composted Plant Pesticide Residues,Incorporated with Trichoderma viride,on Root-Knot Nematode in Balloonflower

Plant pesticide residues, such as chinaberry （Melia toosendan） residue and sand cypress （Sabina vulgaris） residue, are pesticidal plant materials discarded after the bioactive ingredient has been extracted with organic solvents. The only option for botanical pesticide residue utilization has been as landfill. Chinaberry residue （CBR） and sand cypress residue （SCR） were collected and composted in Yangling, Shaanxi Province, China. We studied the effects of chinaberry residue compost （CBRC）, CBRC incorporated with Trichoderma viride （CBRCT）, sand cypress residue compost （SCRC）, and SCRC incorporated with T. viride （SCRCv） on the root-knot nematode, Meloidogyne incognita, infesting the balloonflower （Platycodon grandiflorum）. Bioassay results indicated that stock solutions of the CBRCT and SCRCT extracts significantly inhibited egg hatching and caused high larval mortality, followed in degree by the CBRC and SCRC extracts. The CBR and SCR extracts caused very low inhibition of eggs and larvae. Supplementing potting mixtures with these four composts reduced the severity of root galling and increased the proportion of marketable roots. The severity of root galling decreased and the average weight of the marketable roots increased with an increase in all the composts when supplemented at rates from 5 to 30%. CBR- and SCR-supplemented pot soils also inhibited the nematodes, but CBR and SCR applied to the soil had a phytotoxic effect and inhibited balloonflower growth. Supplementing field soil with the composts reduced the severity of root galling and the populations of southern root-knot nematodes in the soil. CBRCT and SCRCT clearly enhanced the average weight of the marketable roots by 30.45 and 26.64%, respectively. Continuous supplementation with CBRCT or SCRCT in the same field significantly enhanced the control of the root-knot nematode, and the populations of nematodes continued to decrease with second inoculations. The populations of total Trichoderma spp. were distinctly enhanced and were maintained at high levels for a long time in the supplemented soils.

全瓷冠修复+iRoot SP糊剂根管充填治疗隐裂性牙髓炎患者的临床研究

目的:探究全瓷冠修复联合iRoot SP糊剂根管充填在隐裂性牙髓炎治疗中的应用价值。方法:选取2018年4月—2021年3月厦门大学附属第一医院思明分院收治的78例隐裂性牙髓炎患者,按照治疗方法将其分为常规组和治疗组,患者均予以i Root SP糊剂进行根管充填,常规组39例(患牙46颗)采用烤瓷冠进行牙冠修复,治疗组39例(患牙47颗)采用全瓷冠进行牙冠修复。比较两组治疗效果、疼痛情况、炎症指标水平、牙周情况、咀嚼功能、生活质量。结果:治疗组总有效率为94.87%,高于常规组的79.49%,差异有统计学意义(P<0.05)。术后1周,治疗组视觉模拟评分法(visual analogue scale,VAS)评分优于常规组,差异有统计学意义(P<0.05)。术后1 d两组肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素-8(interleukin-8,IL-8)、基质金属蛋白酶-8(matrix metalloproteinase-8,MMP-8)水平升高,但治疗组低于常规组,差异有统计学意义(P<0.05)。两组术后3个月龈沟出血指数(sulcus bleeding index,SBI)、牙龈指数(gingival index,GI)、牙周探诊深度(probing depth,PD)降低,且治疗组低于常规组,差异有统计学意义(P<0.05)。两组术后3个月咀嚼效率、咬合力升高,且治疗组高于常规组,差异有统计学意义(P<0.05)。术后3个月,两组口腔健康影响程度量表(oral health impact profile-14,OHIP-14)评分较术前降低,且治疗组低于常规组,差异有统计学意义(P<0.05)。结论:隐裂性牙髓炎患者iRoot SP糊剂根管充填后采用全瓷冠修复效果显著,能减轻炎症反应,缓解患者疼痛,有助于改善牙周情况,促进咀嚼功能恢复,提高生活质量。

Fusarium pseudograminearum and F.culmorum affect the root system architecture of bread wheat

Yield losses of bread wheat due to crown rot can be more severe when drought conditions occur during the grain-filling period.Root architecture characteristics are important for soil exploration and belowground resource acquisition and are essential for adaptation to water-limited environments.Traits such as root angle,length and density have been strongly associated with acquisition efficiency and contribute to yield stability of the crop.The impact of crown rot pathogens on wheat root architecture is poorly understood.We examined differences in root angle,length and number,as well as dry root weight of the crown rot-susceptible bread wheat cultivar,Livingston inoculated with one of two crown rot pathogens Fusarium culmorum or Fusarium pseudograminearum in a transparent-sided root observation chamber.Significant adverse impacts on plant health and growth were revealed by visual discolouration of the leaf sheaths;fresh and dry shoot weight;leaf area of the oldest and the youngest fully expanded leaf and leaf number.Values of most recorded root system measurements were reduced when inoculated with either F.culmorum or F.pseudograminearum.In contrast,root angle was increased in the presence of F.culmorum but was not significantly changed by F.pseudograminearum.The development of whiteheads and grain losses in bread wheat caused by crown rot have previously been associated with blockages of the vascular systems.The method employed here was able to identify differences in the pathogen impacts on roots,which were not detected using previous systems.This research indicates that in the presence of F.culmorum and F.pseudograminearum infection,not only reductions in the size and biomass of the shoot system but also changes in the length,biomass and architecture of the root system could play an important role in yield loss.

Application of magnetic Barkhausen noise in non-destructive testing fields of residual stress

Magnetic Barkhausen noise （ MBN） is a phenomenon of electromagnetic energy due to the movement of magnetic domain walls inside ferromagnetic materials when they are locally magnetized by an alternating magnetic fields. According to Faraday＇s law of electromagnetic induction, the noise can be received by the coil attached to the surface of the material being magnetized and the noise carries the message of the characteristics of the material such as stresses, hardness, phase content, etc. Based on the characteristic of the noise, researching about the relationship between the residual stress in the welding assembly and the noise are carried out. Furthermore, data process is performed by RMS （Root Mean Square） equation and Power Spectrum analysis.

Phytophthora Root and Crown Rot on Fruit Trees in Bulgaria

Phytophthora root and crown rot was found on the fruit trees in Bulgaria for the first time in the period 1998-1999. Monitoring of the disease spread from 2000 to 2007 points out incidence between 2 and 14 per cent, in some orchards and nurseries in the Southern part of Bulgaria. The following Phytophthora species were identified based on morphological and cultural characteristics, and temperature requirements： Phytophthora cactorum, Phytophthora citrophthora, Phytophthora drechsleri, Phytophthora cryptogea, Phytophthora hybrid specie and Pythium. Prevailing specie was P. cactorum. P. cryptogea and P. cactorum were confirmed by application of molecular methods. Nutritional requirements of P. cactorum and P. citrophthora were studied. Most Nitrogen sources stimulated the mycelial growth of P. cactorum to a higher extend, and reduced the colony size ofP. citrophthora. Different Carbon sources were utilized well by P. cactorum, and only saccharose and maltose had a stimulating effect on the mycelial growth of P. citrophthora. MgSO4.7H20 was the preferred sulfur source for both fungi, as L-cysteine and L-methionine only for P. cactorum. Phytophthora infection leads to physiological changes in the.host plant tissues. The tendency traced out is： about disorders in the amino acid metabolism, increase in the total sugars and slight reduction of the cellulose content. The total nitrogen, phosphorus and potassium content are reduced and the calcium and magnesium are increased. Photosynthesis of inoculated plants was suppressed and transpiration was increased.

Root to crown ratio of permanent teeth of people living in Shanghai

The aim of this study is to assess if there is a significant difference between crown to root ratio of male and female permanent teeth in Chinese people in Shanghai.Methods: For this purpose one thousand four hundred (700,male and 700,female) extracted teeth were collected between age 25-35 and the crown length (CL) and root length (RL) of permanent teeth were measured by a precise caliper.Statistical analyses were performed with the SPSS 17 software by Student's t-test method.Results: The mean crown length of permanent teeth of male was found to be larger than that of female except for maxillary central incisor and the mean root length of male was found to be comparatively larger than that of female.Conclusion: There was a significant difference in root to crown ratio (RL/CL) between male maxillary teeth and mandibular teeth and female ones.The RL/CL ratio of male tends to be larger than those of female in Shanghai population.

Preliminary Study on Mixed Use of Agaricus bisporus Residue and Microbial Agent to Control Cucumber Root-knot Nematode

Single or mixed use ofAgaricus bisporus residue and microbial agent had better control effect on cucumber root-knot nematode disease in greenhouse. The results showed that the control effect of single use of A. b/sporus residue was 32.9% - 34.7%, and the yield increasing rate was 2.1% - 8.7% ; the control effect of mixed use ofA. b/sporus residue and microbial agent was 59. 1% - 63. 6%, and yield increasing rate was 2.6% - 3.5%. The experimental dose had no ad- verse effects on soil physical and chemical properties. The mixed use of A. b/sporus residue and microbial agent was one of the effective ways to control root-knot nematode disease.

二氧化锆髓腔固位冠修复低牙合龈距磨牙的临床效果

目的 评估二氧化锆髓腔固位冠修复低牙合龈距磨牙的临床效果。方法 对2020年1月—2022年1月就诊的46例(50颗)根管治疗后的低牙合龈距磨牙采用二氧化锆髓腔固位冠修复。分别于修复完成后1、6、12个月复查,对修复体完整性、邻接紧密度、边缘密合情况、基牙情况、牙周状况及修复体松动或脱落情况进行评估。结果 1个月复查,50颗磨牙修复后各项评价指标均达到临床可接受水平。6个月复查,6颗患牙牙龈轻度充血,修复体及基牙牙体无异常。12个月复查,仅2颗患牙修复体邻接关系欠佳;2颗患牙牙龈轻度充血,未发现修复体及基牙牙体问题。结论 对根管治疗后的低牙合龈距磨牙采用二氧化锆髓腔固位冠修复既可保护牙体避免折裂,又可提升黏结效果且兼具美观,临床应用效果良好。

良性阵发性位置性眩晕的临床特征及心理因素对复位后残余症状的影响研究

背景良性阵发性位置性眩晕(BPPV)是以具有自限性、易反复发作为特点的临床常见病,手法复位治疗可以取得较好疗效,复位后部分患者会出现残余症状。近年来对BPPV治疗效果影响因素的研究较多,但对具体病因间的治疗效果比较及残余症状发生的影响因素仍有待探讨。目的分析继发性BPPV的临床特征,探讨BPPV的病因分类对疾病复发率的影响及BPPV复位后发生残余症状的影响因素。方法选取2019年4月—2021年4月就诊于吉林大学第一医院耳鼻咽喉头颈外科眩晕门诊及耳内科住院患者中确诊为BPPV的患者共340例,患者均同意行手法复位治疗。按是否存在原发病将患者分为原发性BPPV(原发组)、继发性BPPV(继发组)。继发组再按病因的不同分为5个亚组,主要病因包括突发性聋(SSNHL)、前庭性偏头痛(VM)、梅尼埃病(MD)、前庭神经炎(VN)、其他(如颅脑及耳部手术、Hunt综合征、颞骨骨折等)。比较原发组、继发组之间的临床特征及预后情况。随访至首次复位后3个月,再按患者随访期内有无残余症状发生将患者分为出现残余症状组、未出现残余症状组。比较两组间临床特征及不同时段(诊断时、治疗后4周、治疗后3个月)焦虑自评量表(SAS)、抑郁自评量表(SDS)评分的差异,分析BPPV复位后发生残余症状的独立影响因素。结果340例患者中,原发组184例(54.1%)、继发组156例(45.9%)。继发组较原发组患者发病年龄小,经2次以上复位治疗所占比例高,一次复位成功率低,3个月内复发率、残余症状发生率、诊断时SAS评分、诊断时SDS评分高(P<0.05)。继发性BPPV患者中不同病因患者年龄比较,差异有统计学意义(P<0.05);其中其他(如颅脑及耳部手术、Hunt综合征、颞骨骨折等)病因患者年龄小于SSNHL、VM、MD、VN患者(P<0.05)。继发性BPPV患者中不同病因患者性别、受累半规管、复位次数、一次复位成功率、3个月内复发率、残余症状发生率及各时段SAS、SDS评分比较,差异无统计学意义(P>0.05)。首次复位后3个月,出现残余症状组133例,未出现残余症状组207例。残余症状主要表现为头部昏沉感(59.40%,79/133)、不稳感(24.06%,32/133)及头颈部不适(9.77%,13/133),出现两种及以上症状者占6.77%(9/133)。出现残余症状组继发性病因所占比例、复位次数>2次所占比例高于未出现残余症状组(P<0.05);出现残余症状组伴随疾病复发所占比例少于未出现残余症状组,诊断时、治疗后4周、治疗后3个月SAS、SDS评分高于未出现残余症状组(P<0.01)。多因素Logistic回归分析结果显示,诊断时SAS评分(OR=1.231,95%CI=1.117~1.357,P<0.001)、SDS评分(OR=1.209,95%CI=1.113~1.314,P<0.001)是BPPV患者复位后残余症状发生的影响因素。结论继发性BPPV具有复位后残余症状发生率较高、复发率高的特点,焦虑、抑郁情绪会影响复位后残余症状的发生。

三维打印导板在残冠残根根管治疗中的应用

目的:探讨三维打印导板在残冠残根根管治疗中的应用疗效。方法:选取72例残冠残根患者作为研究对象,随机分为两组。导板组三维打印导板重建残冠残根冠方平面,确定参照点;对照组在残冠残根剩余牙体边缘或邻牙边缘找寻参照点,两组均采用Protaper Gold器械预备结合热牙胶垂直加压充填。对两组各项指标及疗效进行分析。结果:导板组患者主尖就位率、恰充率、成功率、充填精确性均优于对照组,且平均治疗时间也短于对照组,差异均具有统计学意义(P<0.05);同时导板组患者前磨牙与磨牙的精确性差异无统计学意义(P>0.05),而对照组患者前磨牙与磨牙的精确性差异有统计学意义(P<0.05)。结论:残冠残根根管治疗中采用三维打印导板恢复冠方参照点,能有效减小根管治疗误差,提高治疗效率和成功率,增加患牙远期留存率。

番茄颈腐根腐病病原菌鉴定及抗性品种筛选

番茄颈腐根腐病是设施番茄冬春生产中最严重的病害之一,严重威胁我国设施番茄的安全生产。近年来番茄颈腐根腐病在我国番茄主产区发生日益严重,培育抗病品种是防治该病最经济有效的方法。本试验采集典型症状的发病植株进行病原菌分离纯化,综合运用形态学观察、分子生物学鉴定和致病性测定方法,确定病原菌为尖孢镰刀菌番茄颈腐根腐病专化型(Fusarium oxysporum f.sp.radicis-lycopersici,Forl)。之后利用分离的病原菌通过苗期人工接种鉴定结合抗性基因分子标记方法,对32个番茄商品种进行抗颈腐根腐病鉴定分析,结果显示有18个表现抗病,与分子标记Frl-ZL的鉴定结果一致,可用于番茄抗颈腐根腐病育种或生产。

纤维桩+复合树脂+氧化锆全瓷冠修复根管治疗后后牙楔状缺损的疗效分析

目的:探究纤维桩+复合树脂+氧化锆全瓷冠修复根管治疗后后牙楔状缺损患者的效果及美观满意度。方法:纳入2022年1月-2023年1月在笔者医院就诊的102例后牙楔状缺损患者,根据患者自主选择意愿分为研究组(n=50)和对照组(n=52),对照组行金属桩核+金属烤瓷冠修复,研究组行纤维桩+复合树脂+氧化锆全瓷冠修复。6个月后,对比两组临床疗效,观察两组牙周健康情况(牙龈指数、菌斑指数、龈沟出血指数),检测牙周炎症[肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)、白细胞介素-4(Interleukin-4,IL-4)、白细胞介素-6(Interleukin-6,IL-6)],调查美观满意度[美国公共健康服务标准(United states public health service,USPHS)]和实用度(咀嚼功能、咬合情况、语言功能),比较两组并发症发生情况。结果:治疗后,研究组治疗有效率达92.00%,高于对照组的76.92%(P<0.05);两组牙周健康相关指数及TNF-α、IL-4、IL-6均较治疗前降低,且研究组降低幅度大于对照组(P<0.05);治疗后,研究组牙齿表面形态、色泽协调性、边缘着色满意度均高于对照组(P<0.05),两组咀嚼功能、咬合情况、语言功能均较治疗前提高,但差异无统计学意义(P>0.05);两组并发症发生率比较治疗组低于对照组(P<0.05)。结论:采用纤维桩+复合树脂+氧化锆全瓷冠修复根管治疗后后牙楔状缺损能够减轻炎症反应,提升患者牙周健康,增加美观满意度及实用度,疗效显著,安全性高。

地膜残留对内蒙古河套灌区玉米生长及土壤环境的影响

以内蒙古河套灌区覆膜玉米农田残膜分布状态为研究对象,设置0(对照CK)、75kg·hm^(-2)、150kg·hm^(-2)、300kg·hm^(-2)、450kg·hm^(-2)和600kg·hm^(-2)共6个残膜量梯度,分析不同残膜量对玉米产量及构成要素、根系质量及主根数、土壤含水率及容重的影响。结果表明:(1)残膜量与玉米产量呈负相关关系,残膜量超过300kg·hm^(-2)时玉米产量与对照产量差异显著(P<0.05)。随残膜量从0增加到600kg·hm^(-2),玉米秃尖增加,百粒重显著降低(P<0.05)。(2)增加残膜量降低了玉米根系质量和主根数,玉米根系自土壤汲取水分和营养的能力下降。(3)土壤残膜阻碍土壤水分运移,残膜量在300~450kg·hm^(-2)土壤水分下渗缓慢;残膜量超过600kg·hm^(-2)阻碍土壤毛细管水的运移和降水的渗透。采用科学合理的土壤残膜污染治理与地膜回收途径,减少土壤地膜残留,有助于促进玉米产量和土壤质量提升,实现农业绿色可持续发展。

牙周内窥镜与离体观察牙石残留率的对比研究

目的 通过牙周内窥镜观察无保留价值的牙周炎患牙经龈下刮治后残留牙石部位及牙石量,比较镜下根面牙石残留率与离体牙根面牙石的残留率的差异。方法 纳入23例患者33颗牙周炎患牙132个牙根面作为研究对象,进行龈下刮治及根面平整术,牙周内窥镜下采集牙周袋内牙石残留情况、计算牙石残留率,与拔除患牙后根面牙石残留率对比研究,分析内窥镜对牙周袋内根面观察的准确性。结果 前牙和下颌磨牙两者观察的结果没有统计学差异,但在前磨牙和上颌磨牙的对比发现,内窥镜观察的牙石残留率要低于体外直视情况,结果具有统计学差异(P <0.05)。前牙组各个牙根面牙石残留率基本一致,无统计学差异。在前磨牙组的远中根面、上颌磨牙的颊侧和远中根面、下颌磨牙的远中根面两者的观察结果具有统计学差异(P <0.05)。结论牙周内窥镜可以直视看到龈下牙根表面,在其辅助下可以更彻底地清除龈下牙石,在前牙区牙周内窥镜的观察效果显著。

维吾尔族与汉族不同矢状骨面型人群前牙冠根比研究

目的:研究维吾尔族与汉族不同矢状骨面型人群前牙冠根比。方法:选取符合纳入标准的236例CBCT影像资料,按照矢状骨面型分为4组。A组:骨性Ⅰ类(汉族30例,维吾尔族30例),B组:骨性Ⅱ类1分类(汉族30例,维吾尔族30例);C组:骨性Ⅱ类2分类(汉族30例,维吾尔族28例);D组:骨性Ⅲ类(汉族30例,维吾尔族28例)。测量上下颌前牙根长、冠长,计算冠根比,并进行统计学分析。结果:①B组中,维吾尔族与汉族上颌切牙、下颌尖牙冠根比差异有统计学意义(P<0.05);C组中,维吾尔族与汉族下颌侧切牙冠根比差异有统计学意义(P<0.05)。②在汉族四组比较中,D组上下颌前牙冠根比大于A、B组,C组上颌前牙冠根比大于B组,C组上颌切牙冠根比大于A组(P<0.05);在维吾尔族四组比较中,D组上下颌前牙冠根比大于A、B组,C组上颌前牙冠根比大于B组,C组上颌切牙冠根比大于A组(P<0.05)。结论:维吾尔族与汉族在骨性Ⅱ类1分类上颌切牙、下颌尖牙和骨性Ⅱ类2分类的下颌侧切牙冠根比具有差异性,种族是影响上下颌前牙冠根比的一个重要因素。维吾尔族、汉族的骨性Ⅲ类及骨性Ⅱ类2分类冠根比相对较大,正畸医生应根据冠根比设计矫治方案,并在矫治过程中密切关注冠根比变化。

磨牙区不同冠根比例种植体的动力学及疲劳分析研究

目的 探讨磨牙区种植体长度一致下,二期修复时产生的不同种植体冠根比例对种植体系统及周围骨的受力影响,从而获得磨牙区最适合冠根比值区间,为增加种植体临床寿命提供新思路。方法 通过三维有限元方法分析冠根比例为1∶1.5、1∶1、1.5∶1、2∶1、2.5∶1、3∶1的种植体系统的基台、中央螺丝、种植体、皮质骨和松质骨受力情况、疲劳寿命和安全系数。结果 在动态载荷作用力下,种植体构件和周围骨受力随冠根比例增加而增大。种植体系统应力集中在基台和种植体连接处。疲劳寿命和安全系数随着冠根比例增加而减小。结论 在种植体冠根比例大于1的情况下,基台-种植体连接处发生疲劳折断是种植体的潜在危险之一。冠根比例≤1时,种植体各构件可以获得良好的预后和远期效应。但由于有限元方法的特殊性,还有待临床进一步的深入研究。

葛根渣中资源性化学成分分析及膳食纤维提取工艺研究

目的对葛根渣中资源性化学成分进行分析,并考察膳食纤维提取最佳工艺,以期为发现葛根渣资源价值和提升资源化利用效率提供参考。方法通过苯酚-硫酸法、酸碱消煮法分别对葛根渣中的多糖和粗纤维含量进行测定分析,基于单因素试验采用α-淀粉酶、糖化酶和木瓜蛋白酶进行膳食纤维的制备,并测定膳食纤维的膨胀力,确定最佳工艺参数。结果葛根渣中多糖含量为10.30%,粗纤维含量为15.58%;酶法制备膳食纤维的最佳工艺条件为:复合酶(α-淀粉酶、糖化酶)添加比例1:3、添加总量4%、酶解时间75 min、酶解温度65℃,蛋白酶添加总量为0.3%。结论葛根渣中多糖、粗纤维等资源性化学成分丰富,所建立的膳食纤维提取工艺可行,研究结果可为葛根渣的转化增效及粗细高值化利用模式提供科学依据。