BACKGROUND & AIMS: :To study the force-velocity characteristics of human knee-hip extension movement, a dynamometer, in which force was controlled by a servo system, was developed. Seated subjects pressed either bilaterally or unilaterally a force plate, a horizontal position of which was servo-controlled so as to equalize the measured force and a force command generated by a computer at a time resolution of 2 ms (force clamp). The force command was based on the relation between maximum isometric force and foot position within the range between 70% and 90% of "leg length" (LL: longitudinal distance between the sole of the foot and the hip joint), so that the same force relative to the maximum isometric force was consistently applied regardless of the foot position. By regulating the force according to this function, the force-velocity relation was determined. The force-velocity relation obtained was described by a linear function (n=17, r=-0.986 for 80% LL, r=-0.968 for 85% LL) within a range of force between 0.1 and 0.8F(0) (maximum isometric force). The maximum force extrapolated from the linear regression (F(max)) coincided with F(0) (n=17, F(0)/F(max)=1.00+/-0.09 for 80% LL and 1.00+/-0.20 for 85% LL). Also, the velocity at zero force (V(max)) was obtained from the extrapolation. When compared to the bilateral movements, unilateral movements gave rise to a smaller F(max) but the same V(max), suggesting that V(max) is independent of force and therefore represents the proper unloaded velocity. It is suggested that some neural mechanisms may be involved in the force-velocity relation of the knee-hip extension movement, and make it exhibit a linear appearance rather than a hyperbola.

背景与目标： : 为了研究人体膝关节-髋关节伸展运动的力-速度特性，开发了一种测力计，该测力计由伺服系统控制。就座的对象在两侧或一侧按压一个测力板，其水平位置受到伺服控制，以使测得的力和计算机以2 ms的时间分辨率 (力夹) 产生的力命令相等。力命令基于最大等距力和足部位置之间的关系，范围在 “腿长” 的70% 和90% 之间 (LL: 脚底和髋关节之间的纵向距离)，因此，无论脚的位置如何，都始终施加相对于最大等距力的相同力。通过根据此函数调节力，确定了力-速度关系。在0.1和0.8F(0) (最大等距力) 之间的力范围内，通过线性函数 (n = 17，对于80% LL，r =-0.986，对于85% LL，r =-0.968) 描述获得的力-速度关系。从线性回归外推的最大力 (F(max)) 与F(0) 一致 (对于80% LL，n = 17，F(0)/F(max)= 1.00 +/-0.09，对于85% LL，1.00 +/-0.20)。此外，通过外推获得了零力 (V(max)) 的速度。与双边运动相比，单边运动产生的F(max) 较小，但V(max) 相同，这表明V(max) 与力无关，因此代表适当的空载速度。建议某些神经机制可能参与膝髋伸展运动的力-速度关系，并使其表现出线性外观而不是双曲线。

BACKGROUND & AIMS: :This report is a study of structure, castability, mechanical properties as well as corrosion behaviour of titanium doped with up to 5 weight percentage (wt%) of a series of alloy elements, including Ta, Mo, Nb, Hf, Zr, Sn, Bi and Ag. The results indicate that, with addition of 1 wt% alloy element, Bi and Mo were most effective in enhancing the castability of titanium. With more alloy elements added, the castability values of most alloys more or less decreased. Except Ti-Mo system, all Ti alloys with a fine acicular morphology had the same crystal structure (hcp) as that of c.p. Ti with a typical lath type morphology. When 3 wt% or more Mo was added, a finer orthorhombic alpha'' phase was formed. The microhardness and bending strength values of Ti alloys were all higher than those of c.p. Ti. Among all alloys, Ti-Mo system exhibited the highest hardness and strength level. For a certain alloy, the bending strength did not necessarily increase with its alloy content. Except Ti-5Zr and Ti-Mo alloys, the bending moduli of most alloy systems were not much different from that of c.p. Ti. All alloys showed an excellent resistance to corrosion in Hanks' solution at 37 degrees C.

背景与目标： : 本报告研究了掺有高达5重量百分比 (wt %) 的一系列合金元素 (包括Ta，Mo，Nb，Hf，Zr，Sn，Bi和Ag) 的钛的结构，可铸造性，机械性能以及腐蚀行为。结果表明，添加1 wt % 合金元素时，Bi和Mo最有效地提高了钛的可铸造性。随着添加更多的合金元素，大多数合金的可铸造性值或多或少会降低。除Ti-Mo体系外，所有具有细针状形态的Ti合金均具有与c.p.相同的晶体结构 (hcp)。具有典型板条型形态的Ti。当添加3 wt % 或更多Mo时，形成了更细的正交晶型 α'' 相。Ti合金的显微硬度和弯曲强度值均高于c.p.Ti。在所有合金中，Ti-Mo体系表现出最高的硬度和强度水平。对于某种合金，弯曲强度不一定随其合金含量而增加。除Ti-5Zr和Ti-Mo合金外，大多数合金体系的弯曲模量与c.p.没有太大差异。Ti。所有合金在汉克斯溶液中在37 ℃ 下均表现出优异的耐腐蚀性。

BACKGROUND & AIMS: :In this study, the distribution, transfer and fate of both polychlorinated biphenyls (PCBs) and cyanotoxins via phytoplankton routes were systematically investigated in two Chinese lakes. Results indicated that PCB adsorption/bioaccumulation dynamics has significantly positive correlations with the biomass of green alga and diatoms. Total lipid content of phytoplankton is the major factor that influences PCB adsorption/bioaccumulation. Cyanobacterial blooms with relatively lower lipid content could also absorb high amount of PCBs due to their high cell density in the water columns, and this process was proposed as major route for the transfer of PCBs in Chinese eutrophic freshwater. According to these findings, a novel route on fates of PCBs via phytoplankton and a green bioadsorption concept were proposed and confirmed. In the practice of mechanical collections of bloom biomass from Lake Taihu, cyanotoxin/cyanobacteria and PCBs were found to be removed simultaneously very efficiently followed this theory.

背景与目标： : 在这项研究中，系统地研究了两个中国湖泊中通过浮游植物路线的多氯联苯 (pcb) 和氰基毒素的分布，转移和命运。结果表明，PCB的吸附/生物蓄积动力学与绿藻和硅藻的生物量呈显着正相关。浮游植物的总脂质含量是影响PCB吸附/生物积累的主要因素。由于水柱中细胞密度高，脂质含量相对较低的蓝藻水华也可以吸收大量的多氯联苯，这一过程被认为是中国富营养化淡水中多氯联苯转移的主要途径。根据这些发现，提出并证实了通过浮游植物获得多氯联苯命运的新途径和绿色生物吸附概念。在机械收集太湖盛开生物质的实践中，发现根据该理论同时非常有效地去除了氰基毒素/蓝细菌和多氯联苯。

BACKGROUND & AIMS: OBJECTIVES:The purposes of this study included the following: (1) to predict L3 contact force during side-lying lumbar manipulation by combining direct and indirect measurements into a single mathematical framework and (2) to assess the accuracy and confidence of predicting L3 contact force using common least squares (CLS) and weighted least squares (WLS) methods. METHODS:Five participants with no history of lumbar pain underwent 10 high-velocity, low-amplitude lumbar spinal manipulations at L3 in a side-lying position. Data from 5 low-force criterion standard trials where the L3 contact force was directly measured were used to generate participant-specific force prediction algorithms. These algorithms were used to predict L3 contact force in 5 experimental trials performed at therapeutic levels. The accuracy and effectiveness of CLS and WLS methods were compared. RESULTS:Differences between the CLS-predicted forces and the criterion standard-measured forces were 621.0 ± 193.5 N. Differences between the WLS-predicted forces and the criterion standard-measured forces were -3.6 ± 9.1 N. The 95% limits of agreement ranged from 234.0 to 1008.0 N for the CLS and -21.9 to 14.7 N for the WLS. During both the criterion standard and experimental trials, the CLS overestimated contact forces with larger variance than the WLS. CONCLUSION:This novel method to predict spinal contact force combines direct and indirect measurements into a single framework and preserves clinically relevant practitioner-participant contacts. As advanced instrumentation becomes available, this framework will enable advancements in training and high-quality research on mechanisms of spinal manipulative therapy.

背景与目标：

BACKGROUND & AIMS: :A three-dimensional static model is described to evaluate the forces on low-back muscles and on the spine during manual handling tasks and other forceful activities. It is simple to use either with a calculator or programmed onto a micro-computer, whilst being more accurate than existing simple models. Comparisons are made with a more sophisticated model that requires mathematical libraries and programming skills. As predictions are similar, so is the area of validity: the proposed model's accuracy is good for light tasks but poorer for strenuous ones.

背景与目标： : 描述了一个三维静态模型，以评估在手动处理任务和其他有力活动期间对下背部肌肉和脊柱的作用力。它可以简单地与计算器一起使用或编程到微型计算机上，同时比现有的简单模型更准确。使用需要数学库和编程技能的更复杂的模型进行比较。由于预测是相似的，因此有效性领域也是相似的: 所提出的模型的准确性对于轻型任务是好的，而对于繁重的任务则较差。

BACKGROUND & AIMS: :Healing of the rat Achilles tendon is sensitive to mechanical loading, and the callus strength is reduced by 3/4 after 14 days, if loading is prevented. Exogenous GDFs stimulate tendon healing. This response is influenced by loading: without loading, cartilage and bone formation is initiated. This implies BMP signaling is crucial during tendon healing and influenced by mechanical loading. We therefore asked if mechanical loading influences the gene expression of the BMP signaling system in intact and healing tendons, and how the BMP signaling system changes during healing. The genes were four BMPs (OP-1/BMP-7, GDF-5/CDMP-1/BMP-14, GDF-6/CDMP-2/BMP-13, and GDF-7/CDMP-3/BMP-12), two receptors (BMPR1b and BMPR2), and the antagonists follistatin and noggin. The Achilles tendon was transected in rats and left to heal. Half of the rats had one Achilles tendon unloaded by injection of Botox in the calf muscles. Ten tendons were analyzed before transection and for each of four time points. All genes except noggin were expressed at all time points, but followed different patterns during healing. Loading strongly decreased the expression of follistatin, which could lead to increased signaling. The BMP system appears involved in tendon maintenance and healing, and may respond to mechanical loading.

背景与目标： : 大鼠跟腱的愈合对机械负荷敏感，如果防止负荷，则在14天后愈伤组织强度降低3/4。外源性GDFs刺激肌腱愈合。这种反应受负荷影响: 在没有负荷的情况下，开始软骨和骨形成。这意味着BMP信号在肌腱愈合过程中至关重要，并受到机械负荷的影响。因此，我们询问机械负荷是否会影响完整和愈合肌腱中BMP信号系统的基因表达，以及BMP信号系统在愈合过程中如何变化。基因是四个bmp (OP-1/BMP-7，GDF-5/CDMP-1/BMP-14，GDF-6/CDMP-2/BMP-13和GDF-7/CDMP-3/BMP-12)，两个受体 (BMPR1b和BMPR2) 以及拮抗剂follistatin和noggin。在大鼠中横切跟腱并使其愈合。通过在小腿肌肉中注射肉毒杆菌毒素，一半的大鼠的跟腱被卸载。在横切之前和四个时间点中的每一个都分析了十根肌腱。除noggin外，所有基因均在所有时间点表达，但在愈合过程中遵循不同的模式。负载强烈降低了卵泡抑素的表达，这可能导致信号传导增加。BMP系统似乎参与肌腱的维护和愈合，并且可能对机械负荷做出反应。

BACKGROUND & AIMS: BACKGROUND AND PURPOSE:Effects of imatinib mesylate, a Kit receptor tyrosine kinase inhibitor, on spontaneous activity of interstitial cells of Cajal (ICC) and smooth muscles in the stomach were investigated. EXPERIMENTAL APPROACH:Effects of imatinib on spontaneous electrical and mechanical activity were investigated by measuring changes in the membrane potential and tension recorded from smooth muscles of the guinea-pig stomach. Its effects on spontaneous changes in intracellular concentration of Ca(2+) ([Ca(2+)](i)) (Ca(2+) transients) were also examined in fura-2-loaded preparations. KEY RESULTS:Imatinib (1-10 microM) suppressed spontaneous contractions and Ca(2+) transients. Simultaneous recordings of electrical and mechanical activity demonstrated that imatinib (1 microM) reduced the amplitude of spontaneous contractions without suppressing corresponding slow waves. In the presence of nifedipine (1 microM), imatinib (10 microM) reduced the duration of slow waves and follower potentials in the antrum and accelerated their generation, but had little affect on their amplitude. In contrast, imatinib reduced the amplitude of antral slow potentials and slow waves in the corpus. CONCLUSIONS AND IMPLICATIONS:Imatinib may suppress spontaneous contractions of gastric smooth muscles by inhibiting pathways that increase [Ca(2+)](i) in smooth muscles rather than by specifically inhibiting the activity of ICC. A high concentration of imatinib (10 microM) reduced the duration of slow waves or follower potentials in the antrum, which reflect activity of ICC distributed in the myenteric layers (ICC-MY), and suppressed antral slow potentials or corporal slow waves, which reflect activity of ICC within the muscle bundles (ICC-IM), presumably by inhibiting intracellular Ca(2+) handling.

背景与目标：

BACKGROUND & AIMS: :The NCCN HER2 Testing in Breast Cancer Task Force was convened to critically evaluate the ability of the level of HER2 expression or gene amplification in breast cancer tumors to serve as a prognostic and a predictive factor in the metastatic and adjuvant settings, to assess the reliability of the methods of measuring HER2 expression or gene amplification in the laboratory, and to make recommendations regarding the interpretation of test results. The Task Force is a multidisciplinary panel of 24 experts in breast cancer representing the disciplines of medical oncology, pathology, radiation oncology, surgical oncology, epidemiology, and patient advocacy. Invited members included members of the NCCN Breast Cancer Panel and other needed experts selected solely by the NCCN. During a 2-day meeting, individual task force members provided didactic presentations critically evaluating important aspects of HER2 biology and epidemiology: HER2 as a prognostic and predictive factor; results from clinical trials in which trastuzumab was used as a targeted therapy against HER2 in the adjuvant and metastatic settings; the available testing methodologies for HER2, including sensitivity, specificity, and ability to provide prognostic and predictive information; and the principles on which HER2 testing should be based. Each task force member was charged with identifying evidence relevant to their specific expertise and presentation. Following the presentations, an evidence-based consensus approach was used to formulate recommendations relating to the pathologic and clinical application of the evidence to breast cancer patient evaluation and care. In areas of controversy, this process extended beyond the meeting to achieve consensus. The Task Force concluded that accurate assignment of the HER2 status of invasive breast cancer is essential to clinical decision making in the treatment of breast cancer in both adjuvant and metastatic settings. Formal validation and concordance testing should be performed and reported by laboratories performing HER2 testing for clinical purposes. If appropriate quality control/assurance procedures are in place, either immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH) methods may be used. A tumor with an IHC score of 0 or 1+, an average HER2 gene/chromosome 17 ratio of less than 1.8, or an average number of HER2 gene copies/cell of 4 or less as determined by FISH is considered to be HER2 negative. A tumor with an IHC score of 3+, an average HER2 gene/chromosome 17 ratio of greater than 2.2 by FISH, or an average number of HER2 gene copies/cell of 6 or greater is considered HER2 positive. A tumor with an IHC score of 2+ should be further tested using FISH, with HER2 status determined by the FISH result. Tumor samples with an average HER2 gene/chromosome ratio of 1.8 to 2.2 or average number of HER2 gene copies/cell in the range of greater than 4 to less than 6 are considered to be borderline, and strategies to assign the HER2 status of such samples are proposed.

背景与目标： : 乳腺癌工作组的NCCN HER2测试是为了严格评估乳腺癌肿瘤中HER2表达或基因扩增水平在转移和辅助环境中作为预后和预测因素的能力，评估实验室中测量HER2表达或基因扩增方法的可靠性，并就测试结果的解释提出建议。该工作组是由24位乳腺癌专家组成的多学科小组，代表医学肿瘤学，病理学，放射肿瘤学，外科肿瘤学，流行病学和患者倡导等学科。受邀成员包括NCCN乳腺癌小组的成员以及NCCN单独挑选的其他所需专家。在为期2天的会议中，个别工作组成员提供了教学报告，批判性地评估了HER2生物学和流行病学的重要方面: HER2作为预后和预测因素; 曲妥珠单抗在辅助和转移环境中被用作针对HER2的靶向治疗的临床试验结果; HER2可用的测试方法，包括敏感性，特异性以及提供预后和预测信息的能力; 以及HER2测试应基于的原则。每个工作队成员都负责确定与其特定专业知识和陈述相关的证据。演讲结束后，使用基于证据的共识方法来制定有关证据在乳腺癌患者评估和护理中的病理和临床应用的建议。在有争议的领域，这一进程超出了会议的范围，以达成共识。工作组得出结论，准确分配浸润性乳腺癌的HER2状态对于辅助和转移性乳腺癌治疗的临床决策至关重要。正式验证和一致性测试应由进行HER2测试的实验室进行并报告，以用于临床目的。如果有适当的质量控制/保证程序，则可以使用免疫组织化学 (IHC) 或荧光原位杂交 (FISH) 方法。IHC评分为0或1 + 、平均HER2基因/染色体17比率小于1.8、或平均HER2基因拷贝数/细胞数为4或更少 (由FISH测定) 的肿瘤被认为是HER2阴性。IHC评分为3 + 、FISH平均HER2基因/17号染色体比率大于2.2或HER2基因拷贝/细胞平均数为6或更大的肿瘤被认为是HER2阳性。IHC评分为2 + 的肿瘤应使用FISH进一步检测，HER2状态由FISH结果确定。具有1.8至2.2的平均HER2基因/染色体比率或HER2基因拷贝/细胞的平均数在大于4至小于6的范围内的肿瘤样品被认为是临界的，并且提出了分配此类样品的HER2状态的策略。

BACKGROUND & AIMS: :In 1998 the Society for Academic Emergency Medicine's (SAEM's) Board of Directors asked the SAEM Public Health and Education Task Force to develop recommendations for prevention, screening, and counseling activities to be conducted in emergency departments (EDs). The Task Force's work was divided into two phases: 1) a discussion of the rationale for preventive services in the ED, along with generation of a preliminary list of prevention activities that could be studied for ED implementation; and 2) a formal evidence-based review of topics chosen from the preliminary list, along with recommendations for ED implementation and further study. This paper represents Phase I of the project. Phase II, the formal evidence-based review and recommendations, is published separately in this issue.

背景与目标： : 1998年，学术急诊医学协会 (SAEM's) 董事会要求SAEM公共卫生和教育工作组为在急诊科 (EDs) 进行的预防，筛查和咨询活动制定建议。专责小组的工作分为两个阶段: 1) 讨论在ED中提供预防服务的理由，并生成可研究用于ED实施的预防活动的初步清单; 2) 对从初步清单中选择的主题进行正式的循证审查，以及对ED实施和进一步研究的建议。本文代表了该项目的第一阶段。第二阶段，正式的循证审查和建议，在本期单独发表。

BACKGROUND & AIMS: :The aim of this study was to improve the sensitivity of magnetic resonance-acoustic radiation force imaging (MR-ARFI) to minimize pressures required to localize focused ultrasound (FUS) beams, and to establish safe FUS localization parameters for ongoing ultrasound neuromodulation experiments in living non-human primates. We developed an optical tracking method to ensure that the MR-ARFI motion-encoding gradients (MEGs) were aligned with a single-element FUS transducer and that the imaged slice was prescribed at the optically tracked location of the acoustic focus. This method was validated in phantoms, which showed that MR-ARFI-derived displacement sensitivity is maximized when the MR-ARFI MEGs were maximally aligned with the FUS propagation direction. The method was then applied in vivo to acquire displacement images in two healthy macaque monkeys (M fascicularis) which showed the FUS beam within the brain. Temperature images were acquired using MR thermometry to provide an estimate of in vivo brain temperature changes during MR-ARFI, and pressure and thermal simulations of the acoustic pulses were performed using the k-Wave package which showed no significant heating at the focus of the FUS beam. The methods presented here will benefit the multitude of transcranial FUS applications as well as future human applications.

背景与目标： : 这项研究的目的是提高磁共振声辐射力成像 (mr-arfi) 的灵敏度，以最大程度地减少定位聚焦超声 (FUS) 束所需的压力，并为正在进行的超声神经调节实验建立安全的FUS定位参数在活着的非人类灵长类动物中。我们开发了一种光学跟踪方法，以确保mr-arfi运动编码梯度 (meg) 与单元件FUS换能器对齐，并且在声学焦点的光学跟踪位置处规定了成像切片。该方法在幻影中得到验证，表明当MR-ARFI meg与FUS传播方向最大对齐时，MR-ARFI衍生的位移灵敏度最大化。然后将该方法应用于体内，以获取两只健康的猕猴 (M fascicularis) 的位移图像，这些图像显示了大脑中的FUS光束。使用MR测温法获取温度图像，以提供MR-ARFI期间体内大脑温度变化的估计值，并使用k波封装对声脉冲进行压力和热模拟，该封装在FUS的焦点处没有明显的加热束。此处介绍的方法将使多种经颅FUS应用以及未来的人类应用受益。

BACKGROUND & AIMS: BACKGROUND:Neuro-ventilatory efficiency (NVE), defined as the tidal volume to electrical diaphragm-activity ratio (VT/EAdi) at the beginning and end of the weaning process after acute hypoxaemic respiratory failure, may provide valuable information about patient recovery. METHODS:This observational study included 12 patients breathing with neurally adjusted ventilatory assist (NAVA). When a spontaneous breathing trial (SBT) with pressure support of 7 cm H2O and PEEP was unsuccessful, NAVA was used and the level was adjusted to obtain an EAdi of ∼60% of maximal EAdi during SBT. VT and EAdi were recorded continuously. We compared changes in NVE between NAVA and SBT at the first failed and first successful SBT. RESULTS:When patients were switched from NAVA to SBT, NVE was significantly reduced during both unsuccessful and successful SBT (-56 and -38%, respectively); however, this reduction was significantly lower when SBT was successful (P=0.01). Between the first and last day of weaning, we observed that NVE decreased with NAVA [40.6 (27.7-89.5) vs 28.8 (18.6-46.7); P=0.002] with a significant decrease in NAVA level, whereas it remained unchanged during SBT [15.4 (10.7-39.1) vs 19.5 (11.6-29.6); P=0.50] with significant increases in both EAdi and VT and no difference in respiratory rhythm. CONCLUSIONS:These results suggest that in patients after respiratory failure and prolonged mechanical ventilation, changes in VT and NVE, between SBTs are indicative of patient recovery. Larger clinical trials are needed to clarify whether changes in NVE reliably predict weaning in patients ventilated with NAVA.

背景与目标：

BACKGROUND & AIMS: The development of cardiopulmonary bypass (CPB) to support the systemic circulation during cardiac surgical procedures became a clinical reality in 1953. Although the use of CPB for the treatment of post-infarction cardiogenic shock met with little success, intra-aortic balloon counterpulsation was used successfully in 1968 to reduce ischaemic injury in a patient with cardiogenic shock. Today, a broad spectrum of circulatory assist devices for short- and long-term application is available. Three major indication groups for the use of support devices are established. In low-cardiac-output syndrome after cardiac surgical procedures, short-term devices are utilised to enable myocardial recovery. In transplantation candidates suffering from drug-resistant pump failure, the implantation of long-term devices as a bridge to heart transplantation is indicated, and in NYHA class IV patients with contraindications to heart transplantation, the implantation of long-term devices as an alternative to transplantation is under discussion. In the literature, post-cardiotomy support survival is less than 30% on average. About 70% of mechanically bridged patients have survived to undergo heart transplantation and were transplanted with over 90% survival. Major problems during mechanical support are infection, bleeding, and thromboembolism. In view of patients' natural course without support, these clinical results are favourable.

背景与目标： 体外循环 (CPB) 的发展以支持心脏外科手术过程中的全身循环成为临床现实1953年。尽管使用CPB治疗梗塞后心源休克收效甚微，但主动脉内球囊反搏1968年成功用于减少心源休克患者的缺血性损伤。如今，可以使用广泛的短期和长期应用循环辅助设备。建立了使用支持设备的三个主要指示组。在心脏外科手术后的低心输出量综合征中，使用短期设备来恢复心肌。在患有抗药性泵衰竭的移植候选者中，建议植入长期装置作为心脏移植的桥梁，而在NYHA IV级有心脏移植禁忌症的患者中，植入长期装置作为替代移植正在讨论中。在文献中，心脏切开术后支持生存率平均低于30%。大约70% 的机械桥接的患者存活下来接受心脏移植，并以超过90% 的存活率移植。机械支持期间的主要问题是感染，出血和血栓栓塞。鉴于患者的自然病程没有支持，这些临床结果是有利的。

BACKGROUND & AIMS: AIM:The aim of this study was to compare the surface roughness of different composite resins using atomic force microscope (AFM) and a profilometer after storage in different solutions. MATERIALS AND METHODS:Eight different composite resins were used in this study. Twenty specimens of each composite resin material were prepared using a 2-mm thick and 8-mm diameter stainless steel mold. After the composites had been placed in the mold, they were polymerized with a LED curing unit. The surfaces of all specimens were polished using aluminum oxide discs, and the specimens were then divided into four groups. The specimens in the experimental groups were stored in cola, coffee, or red wine, while the control group was stored in distilled water. Specimen surface roughness was examined after 30 days using an AFM and a profilometer, and the data obtained were subjected to analysis. RESULTS:Evaluation of the surface roughness of composite resins using a profilometer revealed no statistically significant difference between the groups, but significant differences were found using the AFM. The mean surface roughness of nanohybrid composites was lower than that of microhybrid composites. CONCLUSIONS:The surface roughness of the composite resins varies with storage in different solutions, depending on the organic matrix structure and inorganic fillers of the resin.

背景与目标：

BACKGROUND & AIMS: :We studied the effect of bioactive compounds Trepel and Suvar on proliferation and enzyme activity of hepatocytes. It was noted that the bioactive compounds activated enzymes in hepatocytes and stimulated their proliferation after mechanical injury to the liver in 18-day-old rats.

背景与目标： : 我们研究了生物活性化合物Trepel和Suvar对肝细胞增殖和酶活性的影响。已注意到，在18天大的大鼠中，生物活性化合物激活了肝细胞中的酶并刺激了其对肝脏的机械损伤后的增殖。

BACKGROUND & AIMS: :There is no consensus on the optimal rehabilitation protocol after platelet-rich plasma (PRP) treatment for tendinopathy despite basic science studies showing the critical role of mechanical loading in the restoration of tendon structure and function posttreatment. In this article, we will review tendon mechanobiology, platelet biology, and review levels I and II Achilles tendon clinical studies paying particular attention to the role of mechanical loading in rehabilitation of injured tendons. Animal studies emphasize the synergistic effect of mechanical tendon loading and PRP to treat tendon injury while clinical studies described minimal details on loading protocols.

背景与目标： : 尽管基础科学研究表明机械负荷在治疗后肌腱结构和功能恢复中的关键作用，但富含血小板血浆 (PRP) 治疗肌腱病后的最佳康复方案尚无共识。在本文中，我们将回顾肌腱力学生物学，血小板生物学，并回顾I和II级跟腱临床研究，特别注意机械负荷在受伤肌腱康复中的作用。动物研究强调机械肌腱加载和PRP在治疗肌腱损伤方面的协同作用，而临床研究则描述了加载方案的最低细节。