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排序方式: 共有4471条查询结果,搜索用时 15 毫秒
91.
目的:研究小腿截肢患者站立状态下假肢对线对下肢受力特性的影响.方法:以假肢侧承重线和重力线作为评价指标,改变假肢矢状面和额状面的对线,采用激光测力平台测量患者静态站立时残侧承重线和重力线的位置,研究下肢受力状况的变化.结果:假肢侧承重线受踝关节对线的影响大于腿管对线调节的影响,并且力线随腿管与接受腔的前倾而前移,而额状面对线的影响很小;矢状面内重力线主要受踝关节对线调节的影响,并且与变化角近似正比例相关.结论:矢状面假肢对线调整对残侧下肢受力状况的影响较大,而额状面的对线调整影响较小. 相似文献
92.
Although ACL deficiency is shown to lead to joint degeneration, few quantitative data are reported on its effect on soft tissue structures surrounding the knee joint, specifically, the posterior cruciate and collateral ligaments. The kinematics of the stifle joint of sheep (N = 5) were measured during “normal” gait, as well as 4 and 20 weeks after ACL transection. These motions were reproduced using a unique robotic manipulator and the loads borne by PCL, MCL, and LCL during gait were determined. Our results demonstrated a significant decrease in mean PCL loads 20 weeks post‐ACL injury, at hoof‐strike (0% of gait, p = 0.034), hoof‐off (66% of gait, p = 0.006), peak‐swing (85% of gait, p = 0.026), and extension‐before‐hoof‐strike (95% of gait, p = 0.028). Mean MCL loads did not significantly increase following ACL transection, maybe due to large between‐animal variation. Finally, mean LCL loads indicated a significant decrease (p < 0.047) at 20 weeks across the entire gait cycle. From a clinical perspective, the load redistributions observed in cruciate and collateral ligaments following ACL injury indicate that these tissues can carry/adapt to the altered mechanical environment of the joint. The considerable variability in the magnitudes of change following ACL injury among animals also simulates clinical variability in humans after trauma. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:431–438, 2014. 相似文献
93.
Bread was a staple in the traditional Mediterranean diet of the early 1960s, as well as nowadays; however, it was a stone ground sourdough bread in Nicotera and probably in the Greek cohorts of the Seven Countries Study. In the present review, the nutritional characteristics of this food are analyzed in relation to its protective effects on coronary heart disease, metabolic diseases and cancer. According to our traditions, cultural heritage and scientific evidence, we propose that only cereal foods with low glycemic index (GI) and rich in fiber have to be placed at the base of the Mediterranean diet pyramid, whereas refined grains and high GI starchy foods have to be sited at the top. 相似文献
94.
Lucijan Skubic Lea Honjak Jeannette P. Staheli Michael R. Dyen Rebecca M. Ducore Lois M. A. Colgin Anne D. Lewis Mario Poljak 《Viruses》2021,13(4)
Papillomaviruses (PVs) are a diverse group of host species-specific DNA viruses, etiologically linked with various benign and malignant neoplasms of cutaneous and mucosal epithelia. Here, we describe the detection and characterization of the first two PVs naturally infecting Japanese macaques (Macaca fuscata), including the determination of their etiological association(s) with the development of original neoplasms. The molecular and phylogenetic analyses were performed on complete genome sequences of Macaca fuscata PV types 1 (MfuPV1) and 2 (MfuPV2), which were completely sequenced in samples of a malignant oral tumor and benign anogenital neoplasm of Japanese macaques, respectively. Subsequently, two type-specific quantitative real-time PCRs were developed to estimate viral loads of MfuPV1 and MfuPV2 and to evaluate their etiological roles. The in silico molecular analyses revealed that both viral genomes encode characteristic PV proteins with conserved functional domains and have a non-coding genomic region with regulatory sequences to regulate and complete the viral life cycle. However, additional experimental evidence is needed to finally confirm the presence and biological functionality of the molecular features of both novel PVs. While MfuPV1, together with PVs identified in other macaques, is classified into the Alphapapillomavirus (Alpha-PV) species 12, MfuPV2 is most likely a representative of the novel viral species within the Alpha-PV genus. Their relatively high viral loads suggest that both PVs are etiologically linked with the development of the original neoplasms. 相似文献
95.
Maria I. Sanchez-Codez Katherine Moyer Isabel Benavente-Fernndez Amy L. Leber Octavio Ramilo Asuncion Mejias 《Viruses》2021,13(2)
The role of rhinoviruses (RVs) in children with clinical syndromes not classically associated with RV infections is not well understood. We analyzed a cohort of children ≤21 years old who were PCR+ for RV at a large Pediatric Hospital from 2011 to 2013. Using univariate and multivariable logistic regression, we analyzed the associations between demographic, clinical characteristics, microbiology data, and clinical outcomes in children with compatible symptoms and incidental RV detection. Of the 2473 children (inpatients and outpatients) with an RV+ PCR, 2382 (96%) had compatible symptoms, and 91 (4%) did not. The overall median age was 14 months and 78% had underlying comorbidities. No differences in RV viral loads were found according to the presence of compatible symptoms, while in children with classic RV symptoms, RV viral loads were higher in single RV infections versus RV viral co-infections. Bacterial co-infections were more common in RV incidental detection (7.6%) than in children with compatible symptoms (1.9%, p < 0.001). The presence of compatible symptoms independently increased the odds ratio (OR, 95% CI) of hospitalization 4.8 (3.1–7.4), prolonged hospital stays 1.9 (1.1–3.1), need for oxygen 12 (5.8–25.0) and pediatric intensive care unit (PICU) admission 4.13 (2.0–8.2). Thus, despite comparable RV loads, disease severity was significantly worse in children with compatible symptoms. 相似文献
96.
JL Adams M Murray N Patel MT Sawkin RC Boardman C Pham H Kaur D Patel JL Yager L Pontiggia J Baxter 《HIV medicine》2021,22(1):28-36
97.
Leandro Neckel Cristian A. Faller Matej Babi
Oscar R. K. Montedo Carlos P. Bergmann Rolf Janssen 《Materials》2021,14(1)
A study on the strength of ceramic fiber bundles based on experimental and computational procedures is presented. Tests were performed on single filaments and bundles composed of two fibers with different nominal fiber counts. A method based on fiber rupture signals was developed to estimate the amount of filament rupture during the test. Through this method, the fiber bundle true strength was determined and its variation with the initial fiber count observed. By using different load-sharing models and the single filament data as input parameter, simulations were also developed to verify this behavior. Through different approaches between experiments and simulations, it was noted that the fiber bundle true strength increased with the fiber count. Moreover, a variation of the fibers’ final proportion in the bundles relative to the initial amount was verified in both approaches. Finally, discussions on the influence of different load-sharing models on the results are presented. 相似文献
98.
目的 研究稳恒磁场对小鼠肾组织中丙二醛 (MDA)含量及谷胱甘肽过氧化物酶 (GSH Px)活性的影响。方法 采用磁感应强度 (B)为 2 4 6± 4 2mT ,42 0± 2 1mT ,63 5± 3 0mT ,85 1± 2 9mT的稳恒磁场分别作用于小鼠 ,每天平均 4h ,1 5d后处死小鼠检测肾脏组织中MDA的含量及GSH Px活性。结果 B为 2 4 6± 4 2mT ,42 0± 2 1mT ,63 5± 3 0mT ,85 1± 2 9mT磁场暴露的小鼠 ,其肾组织中MDA含量较对照组明显减少 (P <0 0 1 ) ,B为 42 0± 2 1mT ,63 5± 3 0mT的磁场暴露的小鼠 ,其肾组织中GSH Px活性明显增加 (P <0 0 1 ) ,但B为 2 4 6±4 2mT ,85 1± 2 9mT时的GSH Px活性没有明显的变化。结论 提示一定磁感应强度的稳恒磁场对小鼠的肾组织的脂质过氧化代谢产生影响 ,降低了氧化物的生成 ,对延缓衰老有积极作用 相似文献
99.
《Sleep medicine》2014,15(8):853-859
Short sleep duration, poor sleep quality, and insomnia frequently characterize sleep in pregnancy during all three trimesters. We aimed: (i) to review the clinical evidence of the association between conditions of sleep loss during pregnancy and adverse pregnancy outcomes; and (ii) to discuss the potential pathophysiological mechanisms that may be involved. A systematic search of cross-sectional, longitudinal studies using Medline, Embase, and PsychINFO, and MeSH headings and key words for conditions of sleep loss such as ‘insomnia’, ‘poor sleep quality’, ‘short sleep duration’, and ‘pregnancy outcome’ was made for papers published between January 1, 1960 and July 2013. Twenty studies met inclusion criteria for sleep loss and pregnancy outcome: seven studies on prenatal depression, three on gestational diabetes, three on hypertension, pre-eclampsia/eclampsia, six on length of labor/type of delivery, eight on preterm birth, and three on birth grow/birth weight. Two main results emerged: (i) conditions of chronic sleep loss are related to adverse pregnancy outcomes; and (ii) chronic sleep loss yields a stress-related hypothalamic–pituitary–adrenal axis and abnormal immune/inflammatory, reaction, which, in turn, influences pregnancy outcome negatively. Chronic sleep loss frequently characterizes sleep throughout the course of pregnancy and may contribute to adverse pregnancy outcomes. Common pathophysiological mechanisms emerged as being related to stress system activation. We propose that in accordance to the allostatic load hypothesis, chronic sleep loss during pregnancy may also be regarded as both a result of stress and a physiological stressor per se, leading to stress ‘overload’. It may account for adverse pregnancy outcomes and somatic and mental disorders in pregnancy. 相似文献
100.