芦笋复合果蔬汁稳定性的研究

探讨了稳定剂对芦笋复合果蔬汁的稳定性的影响.通过单一稳定剂的试验,发现黄原胶、果胶、CMC 3种稳定剂对芦笋复合果蔬汁的稳定效果较好,但是单一稳定剂很难解决芦笋复合果蔬汁长期稳定的问题.采用混合水平正交试验(L18(61×32))设计,对黄原胶、果胶、CMC3种稳定剂进行复配,然后通过6个月的贮藏实验,以相对粘度和浊度为测试指标,确定稳定剂的最佳添加质量分数为果胶0.04%,黄原胶0.06%,CMC 0.06 %.     

冰淇淋复配稳定剂的开发及其稳定机理研究

选用黄原胶、羧甲基纤维素、卡拉胶、魔芋葡甘露聚糖以及瓜尔豆胶等５种多糖进行不同的组合复配，通过对其流变性质的测定以及结合响应曲面分析，确定了５种复配稳定剂中不同多糖的最佳配比，其中４号复配稳定剂制得的冰淇淋具有优良的膨胀性、抗融化性和抗热波动性。运用差扫描量热仪测定了冰淇淋的玻璃相转变温度，并结合其流变性质以及冰晶形成时间的测定，着重讨论了复合多糖稳定剂对于冰晶的形成与冰晶长大的影响，从本质上探讨了复合多糖稳定剂稳定冰淇淋的机理。     

柑桔汁悬浮稳定机理的探讨

柑桔汁的混浊稳定机理研究 .结果表明 ,均质可以降低柑桔汁悬浮颗粒的大小 ,从而提高产品的稳定性 ,但是均质的压力高于 1 9.6MPa时 ,悬浮颗粒过小 ,贮存期间颗粒易合并而破坏混浊稳定性 .添加蔗糖可以增大柑桔汁的密度 ,稳定剂可以提高柑桔汁的粘度 ,从而降低了悬浮颗粒沉降速度 ,提高产品的稳定性 .研究还发现 ,复配稳定剂对柑桔汁稳定作用优于单一稳定剂 ,这是因为大分子之间产生协同作用所致     

稳定剂和乳化剂对低脂冰淇淋品质的影响

实验研究了一种稳定剂和两种乳化剂对低脂冰淇淋品质的影响.通过测定冰淇淋浆料的流变性质和脂肪失稳能力,以及冰淇淋的膨胀率和抗融化性,得出在低脂冰淇淋中稳定剂的添加量最佳质量分数为0.45％,由单甘酯和吐温80复配乳化剂的添加量最佳质量分数为0.1％.     

黄原胶和瓜尔豆胶的复配稳定剂对冰淇淋品质和流变性的影响

研究了黄原胶和瓜尔豆胶的复配胶作为冰淇淋稳定剂对冰淇淋品质和流变性的影响,测定了冰淇淋浆料的粘度,应用小幅振荡测定经硬化后冰淇淋成品的动态粘弹性,以及硬化冰淇淋的硬度和粘结度.结果表明,随复配胶用量的增加,冰淇淋浆料的粘度也随之增加,另外,Power law模型的流动指数和粘度指数、冰淇淋成品储能模量、及硬度、粘结度均呈增加趋势.实验结果还表明,随复配胶用量的增加,冰淇淋的弹性模量和稳定性得以提高.通过测定冰淇淋的膨胀率和抗融性,得出冰淇淋中复配胶的最佳添加量质量分数为0.35%.     

复配香辛料提取物体外阻断N-二甲基亚硝胺生成的效果

在确定桂皮、柚子皮、八角和花椒4种香辛料中活性物质最佳提取条件的基础上,利用所提取的活性物质在不同浓度下进行阻断N-二甲基亚硝胺生成的体外试验,并以不同比例进行复配,根据阻断率选出最佳复配比.结果显示:当桂皮、柚子皮、八角、花椒提取液四者达最佳复配比时,复配液具有较好的阻断效果.     

亲水胶体对含酒精O/W(水包油)乳状液稳定性的影响

研究了卡拉胶、刺槐豆胶,及其混和胶作为稳定剂,对以酪蛋白酸钠稳定的含酒精O/W乳状液体系稳定性的影响.结果表明,单独添加一定浓度的卡拉胶可改善体系的分层稳定性,而单独加入刺槐豆胶会加速体系失稳,当m(卡拉胶)∶m(刺槐豆胶)=4∶1加入到体积分数为15%的酒精乳状液中,加入量为0.02%时体系稳定性最好.同时研究了两多糖的加入方式、热处理时间,以及蔗糖存在下对乳状液稳定性及黏度的影响.结果表明,卡拉胶与刺槐豆胶分别加入到乳状液中稳定效果较好,并且卡拉胶和刺槐豆胶分别在90℃保温6min后加入有利于体系的稳定;质量分数为10%的蔗糖存在增强了复合胶存在下体系的稳定性.     

微管干预剂对缺氧心肌细胞糖酵解途径关键酶的影响

目的 了解微管干预剂对缺氧心肌细胞糖酵解途径关键酶的影响. 方法体外培养心肌细胞,分为单纯缺氧组、缺氧+微管解聚剂(秋水仙碱)组、缺氧+低浓度微管稳定剂组、缺氧+中浓度微管稳定剂组、缺氧+高浓度微管稳定剂组,后3组加入的微管稳定剂为紫杉醇,浓度分别为5、10、15 μmol/L.采用激光共聚焦显微镜观察微管形态学变化,检测细胞活力及己糖激酶、丙酮酸激酶、磷酸果糖激酶、乳酸脱氢酶的活性. 结果缺氧+微管解聚剂组和缺氧+高浓度微管稳定剂组心肌细胞微管结构破坏显著,细胞活力亦明显下降[缺氧1.0 h,2组细胞活力分别为(89.99±3.47)%、(84.56±6.61)%,明显低于单纯缺氧组(97.44±1.76)%(P<0.01)],前3种酶的活性亦明显降低;缺氧+低浓度微管稳定剂组前3种酶的活性与单纯缺氧组基本近似;缺氧+中浓度微管稳定剂组微管结构损伤显著轻于其他组,前3种酶的活性于缺氧6.0 h内高于单纯缺氧组.缺氧后各组乳酸脱氢酶活性升高. 结论适当浓度的微管稳定剂能明显减轻微管结构损伤,促使缺氧早期心肌细胞糖酵解酶活性增强.     

机械瓣置换术后早期患者华法林稳定剂量的影响因素分析

目的对影响心脏机械瓣置换术后早期患者华法林稳定剂量的相关因素进行分析,以期指导患者术后早期的抗凝治疗。方法 2012年7月至2014年4月门诊随访时登记在四川大学华西医院行机械瓣置换术后早期(≤6个月)288例患者的基本信息(姓名、性别、年龄、身高、体质量等)、一般临床资料(心功能、心律、手术方式等)及门诊复查时的抗凝治疗相关数据,其中男93例、女195例,年龄21~68(47.30±9.31)岁。本研究所采用的目标国际标准化比值(INR)范围为1.60~2.20,可接受的INR范围为1.50~2.30。以周为单位进行华法林剂量的调整,当INR超出可接受的范围时进行相应的华法林剂量调整。以纳入患者的性别、年龄、身高、体质量、体质量指数、体表面积及相关临床因素为观察指标,分析这些指标与术后早期患者华法林稳定剂量的相关性。结果性别是影响机械瓣置换术后早期患者华法林稳定剂量的因素之一(P0.05),女性患者术后早期抗凝治疗所需的华法林稳定剂量低于男性患者。而在不同年龄、心律、心功能、手术方式的患者之间华法林稳定剂量的差异并无统计学意义(P0.05)。术前合并的疾病对患者早期华法林稳定剂量无显著影响(P0.05);同期行射频消融术的心房颤动患者则其术后所需的华法林稳定剂量显著低于那些未同期行射频消融术的心房颤动患者(P0.05)。年龄、身高、体质量、体质量指数、体表面积与华法林稳定剂量之间有相关性,其影响程度(R2)分别为1.2%,3.2%,3.5%,1.1%,4.2%;以华法林稳定剂量为因变量,以年龄、身高、体质量、体质量指数、体表面积为自变量的多元回归分析方程可解释6.1%的华法林稳定剂量。结论在机械瓣置换术后早期给予患者抗凝治疗时应考虑不同的术前因素、药物因素及人口学因素对患者华法林稳定剂量的影响;华法林稳定剂量与年龄、身高、体质量、体质量指数、体表面积具有相关性,但只能解释6.1%的华法林稳定剂量,并不能很好地指导这些患者术后的抗凝治疗。     

谷朊粉废水提取物在肉制品中的应用

介绍了一种从谷朊粉废水中提取戊聚糖的工艺,由此工艺得到的产品(戊聚糖质量分数约70%,蛋白质质量分数约20%)能较好地保持戊聚糖的特性.研究了其它添加剂(卡拉胶)对戊聚糖的乳化性,戊聚糖对肉制品持油、持水性以及其质构的影响.谷朊粉废弃水提取物与卡拉胶的复配产品在添加量(质量分数)为6%时能使肉制品有较好的持油性和相应的质构.     

Dynamic glenohumeral stability provided by three heads of the deltoid muscle

The deltoid is a large bulky muscle, comprising approximately 20% of the shoulder muscles. Therefore, the function of the deltoid as a stabilizer is thought to be significant. The current authors quantified dynamic glenohumeral stability provided by three heads of the deltoid by a new biomechanical parameter, the dynamic stability index. The dynamic stability index considers not only the force vectors generated by individual shoulder muscle, but also the concavity compression mechanism. The higher the dynamic stability index, the greater the dynamic stability. The deltoid generated significant shear force and compressive force in the position of anterior shoulder instability. The deltoid provided dynamic stability with the arm in the scapular plane and only decreased the stability of the shoulder with the arm in the coronal plane. The mid and posterior heads should be strengthened vigorously in anterior shoulder instability in conservative and operative treatment, because they provide more stability generating higher compressive force and lower shear force than the anterior head. Scapular muscles should be balanced to avoid the vulnerable glenohumeral position where the arm is extended beyond the scapular plane. Anatomic reattachment of the detached labrum onto the glenoid rim in the anterior instability is important to enhance the effect of compressive force component generated by the muscles.     

腰椎后路手术对硬膜囊容量和脊柱稳定性的影响

目的 :进一步了解腰椎后路手术对脊柱功能的影响 ,为临床合理选择术式提供依据。方法 :采用平行光三维测量系统 ,对 12具人新鲜尸体腰椎实施全椎板切除、半椎板切除及交叉半椎板切除 ,对其屈伸状态下硬膜囊容量和脊柱稳定性的定量变化结果进行双因素方差分析。结果 :腰椎屈曲活动时硬膜囊容量增大 ,仰伸位变小 ;全椎板切除与交叉半椎板切除 ,硬膜囊容量改变相近 ,但均较半椎板切除明显增大 (P <0 0 1) ;任何一种腰椎后路手术 ,均能破坏腰椎稳定性 ,其中半椎板切除与交叉半椎板切除破坏性较小 ,而与全椎板切除相比较 ,后者破坏性大于前二者 (P <0 0 1)。结论 :下腰椎疾病后路手术应尽量保留棘突及其韧带 ,交叉半椎板切除可使椎管得到充分减压 ,同时又较好地保留脊柱的稳定性     

Postural stability during long-term treatment of cancer patients with epidural opioids

Ten cancer patients treated with stable doses of epidural opioids were tested for postural stability. The postural stability was measured using a quantitative Romberg's test, performed on a computerized force-plate system. Sway tendencies in the sagittal and the transverse directions were recorded. The postural stability of the patients was compared with values obtained from healthy controls. Comparing the cancer patients with the controls, postural stability in eight out of ten patients was intact. The study suggests that long-term epidural opioid treatment has little influence on the patient's ability to stand safely.     

Neuromuscular training improves single-limb stability in young female athletes

STUDY DESIGN: Controlled single-group pretest/posttest design. OBJECTIVE: The purpose of this study was to determine if a 6-week neuromuscular training program designed to decrease the incidence of anterior cruciate ligament (ACL) injuries would improve single-limb postural stability in young female athletes. We hypothesized neuromuscular training would result in an improvement in postural stability, with the greatest improvement taking place in the medial-lateral direction. BACKGROUND: Balance training has become a common component of programs designed to prevent ACL injury. Rehabilitation programs can improve postural stability following ACL injury and reconstruction; however, there is limited information available which quantifies improvement of postural stability following neuromuscular training designed to prevent ACL injuries in a healthy population. METHODS AND MEASURES: Forty-one healthy female high school athletes (mean age, 15.3 years; age range, 13-17 years) participated in this study. Single-limb postural stability for both lower extremities was assessed with a Biodex Stability System. The neuromuscular training program consisted of three 90-minute training sessions per week for 6 weeks. Following the completion of the training program, each subject was re-evaluated to determine change in total, anterior-posterior, and medial-lateral single-limb stability. Two-way analysis of variance models were used to determine differences between pretraining and posttraining and between limbs. RESULTS: The subjects showed a significant improvement in single-limb total stability (P = .004) and anterior-posterior stability (P = .001), but not medial-lateral stability (P = .650) for both the right and left lower extremity following training. In addition, the subjects demonstrated significantly better total postural stability on the right side as compared to the left (P = .026). CONCLUSIONS: A 6-week neuromuscular training program designed to decrease the incidence of ACL injuries improves objective measures of total and anterior-posterior single-limb postural stability in high school female athletes.     

Optimizing the glenoid contribution to the stability of a humeral hemiarthroplasty without a prosthetic glenoid

BACKGROUND: In a shoulder requiring arthroplasty, if the glenoid is flat or biconcave, the surgeon can restore the desired glenoid stability by using a glenoid prosthesis with a known surface geometry or by modifying the surface of the glenoid to a geometry that provides the desired glenoid stability. This study tested the hypotheses that (1) the stability provided by the glenoid is reduced by the removal of the articular cartilage; (2) the stability contributed by the glenoid is compromised by loss of its articular cartilage, and this lost stability can be restored by spherical reaming along the glenoid centerline; and (3) the stability of a reamed glenoid is comparable with that of a native glenoid and with that of a polyethylene glenoid with similar surface geometry; and (4) the glenoid stability can be predicted from the glenoid surface geometry. METHODS: The stability provided by the glenoid in a given direction can be characterized by the maximal angle that the humeral joint reaction force can make with the glenoid centerline before the humeral head dislocates; this quantity is defined as the balance stability angle in the specified direction. The balance stability angles were both calculated and measured in eight different directions for an unused polyethylene glenoid component and eleven cadaveric glenoids in four different states: (1) native without the capsule or the rotator cuff, (2) denuded of cartilage and labrum, (3) after reaming the glenoid surface around the glenoid centerline with use of a spherical reamer with a radius of 25 mm, and (4) after reaming around the glenoid centerline with use of a spherical reamer with a radius of 22.5 mm. RESULTS: The calculated and measured balance stability angles for each direction in each glenoid were strongly correlated. Denuding the glenoids of the articular cartilage reduced the glenoid contribution to stability, especially in the posterior direction. Reaming the glenoid restored the stability to values comparable with those of the normal glenoid. For example, the average calculated balance stability angle (and standard deviation) in the posterior direction for all eleven glenoids was 24 degrees for the native glenoids, 14 degrees for the denuded glenoids, 25 degrees for the glenoids reamed to a radius of 25 mm, and 33 degrees for the glenoids reamed to a radius of 22.5 mm. The values for the glenoids reamed to 25 mm (25 degrees ) were similar to those of a polyethylene glenoid of the same radius of curvature. For glenoids reamed to 22.5 mm, the average difference between the actual balance stability angle and that predicted from the glenoid geometry was 3.4 degrees +/- 2.4 degrees. CONCLUSIONS: The glenoid contribution to shoulder stability was decreased by the removal of cartilage and labrum and was restored by spherical reaming to a level similar to resurfacing the glenoid with a polyethylene component.     

A biomechanical comparison of Schuhli nuts or cement augmented screws for plating of humeral fractures

Schuhli locking nuts can be used in poor quality cortical bone to enhance fixation stability as an alternative to cement augmented screws. This study compared the fixation strength and stability of plate constructs using Schuhli locking nuts with standard screws and cement augmented screws for fixation of simulated humeral shaft fractures in a test model with osteoporosis. The constructs were tested in axial compression, 4-point bending, and torsion to determine fixation stability. The humeri were cycled in torsion (4.5 Nm) for 1000 cycles to simulate upper extremity use during the early postoperative period and retested for stability. The Schuhli locking nuts and cement augmented screws had significantly greater fixation stability than the standard screws before (range, 6-14 times greater) and after cycling in torsional loading (range, 3-3.6 times greater). Although cement augmented screws and Schuhli augmentation showed increased fixation stability compared with the standard screws in axial and 4-point bending before cycling (range, 1.3-1.4 times greater), this was not significant. Compared with Schuhli fixation, cement augmented screws showed no significant difference in fixation stability in all loading modes before and after cycling. Schuhli locking nuts offer the stability of cement augmentation while avoiding its potential adverse effects on fracture healing with extravasation and thermal necrosis.     

盂肱关节骨性结构对肩关节稳定性影响的研究进展

目的对盂肱关节骨性结构对肩关节稳定性影响的研究作一综述。方法查阅近年来国内外有关肩关节稳定性影响因素及盂肱关节骨性结构在肩关节稳定性中作用的文献,并进行分析总结。结果盂肱关节骨性结构影响肩关节稳定的具体因素包括盂肱关节骨性结构嵌合匹配指数、盂肱关节的外形和弧度、头-盂表面的几何形态关系(关节盂扭转角及头干角)等。结论 以往的研究经验和临床报道已初步确定了骨性结构与肩关节不稳之间的关系,但仍有许多系统的、多方面(包括解剖、生物力学、临床)的研究有待进一步完善。     

Intrinsic stability of unused and retrieved polyethylene glenoid components

The surface geometry of polyethylene components can be altered by in vivo use. The purpose of this investigation is to document the effects of these changes on the intrinsic stability provided by the glenoid component. We validated a method of measuring the intrinsic stability of glenoid components as indicated by the balance stability angle (the maximal angle between the glenoid centerline and the resultant humeral force before dislocation of the humeral head occurs). We compared observed values with those predicted for unused glenoid components for which the geometry was known. We then applied this method to retrieved glenoid components in which the surface geometry had been altered by in vivo use. The balance stability angles measured in retrieved glenoids were often substantially reduced: 11 of 24 glenoids had diminished balance stability angles of at least 30% in at least one direction. We concluded that the surface geometry of polyethylene glenoid components can be altered by in vivo use in a manner that may compromise their contribution to glenohumeral stability.     

Controversies in soft-tissue anterior cruciate ligament reconstruction: grafts, bundles, tunnels, fixation, and harvest

Increased stability has been reported with both autografts and allografts for anterior cruciate ligament (ACL) reconstruction. However, meta-analysis has shown significantly lower overall knee stability rates and more than double the abnormal stability rate with allografts. Some issues surrounding allograft sterilization (ie, risk of disease transmission) are unresolved, and cost is also a concern. Single-bundle ACL reconstruction can produce high stability rates when tunnels are properly placed, but there is evidence that double-bundle repair may offer greater rotatory stability. Cortical fixation has been associated with increased stability owing to the high stiffness of cortical bone. Anterior and posterior approaches are both recommended. The controversy related to single-bundle versus double-bundle ACL reconstruction remains unresolved.     

A modular spinal rod linkage system to provide rotational stability

The effect of cross linkage on the in vitro stability of paired Harrington distraction rods was studied in an unstable fracture model using calf spine segments. Cross linkage used in conjunction with sublaminar wires significantly improved torsional stability, improved lateral bending stability, and had no adverse affect on stability for axial, forward flexion, or extension loading compared to rods alone, rods with bridges, and wired rods.