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11.
The aim of this study was to quantitatively describe the relationships between joint angles and muscle architecture (lengths (Lf) and angles (Θf) of fascicles) of human triceps surae [medial (MG) and lateral (LG) gastrocnemius and soleus (SOL) muscles] in vivo for three men-cosmonaut after long-duration spaceflight. Sagittal sonographs of MG, LG, SOL were taken at ankle was positioned at 15° (dorsiflexion), 0° (neutral position), +15°, and +30° (plantarflexion), with the knee at 90° at rest and after a long-duration spaceflight. At each position, longitudinal ultrasonic images of the MG and LG and SOL were obtained while the cosmonauts was relaxed from which fascicle lengths and angles with respect to the aponeuroses were determined. After space flight plantarflexor force declined significantly (26%; p < 0.001). The internal architecture of the GM, and LG, and SOL muscle was significantly altered. In the passive condition, Lf changed from 45, 53, and 39 mm (knee, 0°, ankle, −15°) to 26, 33, and 28 mm (knee, 90° ankle, 30°) for MG, LG, and SOL, respectively. Different lengths and angles of fascicles, and their changes by contraction, might be related to differences in force-producing capabilities of the muscles and elastic characteristics of tendons and aponeuroses. The three heads of the triceps surae muscle substantially differ in architecture, which probably reflects their functional roles. Differences in fiber length and pennation angle that were observed among the muscles and could be associated with differences in force production and in elastic properties of musculo-tendinous complex and aponeuroses.  相似文献   
12.
目的:研究彩色多普勒超声联合癌胚抗原(CEA)和糖链抗原15-3(CA15-3)检测在乳腺癌诊断中的价值。方法:选取我院2010年2月~2011年1月的98例乳腺肿块患者,患者均行彩色多普勒超声检查,采用化学发光免疫法检测血清CEA、CA-153水平,并结合常规活检和术后诊断进行统计学分析。对比三者联合检测与单一检测的敏感性、准确性。结果:彩色多普勒超声、血清CEA、CA15-3检查及三者联合检查诊断乳腺癌的敏感性、准确性分别为86.11%、30.56%、47.22%、97.22%和88.78%、73.47%、77.55%、94.90%,联合检查的准确性、敏感性高于单一检查,差异有统计学意义(P0.05)。结论:彩色多普勒超声检测方法联合CEA、CA15-3检查可提升乳腺癌诊断的准确性和敏感性,降低漏诊率。  相似文献   
13.
Objectives:Stretch reflex responses were considered to be affected by the velocity of muscle fiber lengthening and angular velocity. However, the results of previous studies in vivo and in vitro are inconsistent in this regard. The purpose of the present study was to investigate the effects of the velocity of fascicle lengthening on the amplitude of the stretch reflex for each trial with a high angular velocity and wide range of motion.Methods:Thirteen healthy men volunteered for this study. While the ankle was passively moved from 100 to 80 deg at five different angular velocities (100, 200, 300, 500, and 600 deg⋅s-1), the velocity of fascicle lengthening in the soleus muscle was measured using ultrasonography. In addition, the amplitude of the short latency stretch reflex in the soleus muscle was also measured.Results:As angular velocity increased, the amplitude of the stretch reflex and velocity of fascicle lengthening significantly increased (both p<0.001). For each trial in all subjects, the amplitude of the stretch reflex was not correlated with the velocity of fascicle lengthening at any of the angular velocities.Conclusion:In conclusion, the stretch reflex size is not related to the fascicle behavior in each trial.  相似文献   
14.
Follicular growth in the feline ovary is usually detected indirectly, through behavior observation, vaginal smears, or more invasively, by estradiol assay in blood. This study was designed to describe follicular dynamics by transabdominal ultrasonography. Secondly, the stage of follicular growth was associated to behavioral and vaginal changes. Ovarian ultrasonography was performed during nine anovulatory and 12 ovulatory cycles. Forty-eight follicles were followed during anovulatory cycles: on the first day of estrus behavior, 4.8 ± 0.2 follicles (2 to 7 per female) of 2.3 ± 0.01 mm mean diameter were present. Follicular growth continued at a rate of 0.2 ± 0.04 mm per day. At least one follicle in the cohort reached a diameter greater than 3.0 mm. Maximal follicular growth (when one follicle of the cohort reached the maximal diameter observed for the whole estrus) was reached 3.8 ± 0.3 days after the onset of estrus with the largest follicle reaching a diameter of 3.5 ± 0.04 mm. Growth of the various follicles within a cohort was not exactly synchronous. When no ovulation took place, the follicular diameter decreased by 0.1 ± 0.01 mm per day until the end of estrus. The first day after the end of behavioral estrus, the diameter of the largest follicle in each cohort was 2.7 ± 0.05 mm. No correlation was found between follicular development and either vaginal smear characteristics, or time elapsed since the onset of estrus. When ovulations were mechanically induced after one follicle had reached 3.0 mm in diameter, artificial insemination produced normal pregnancy rate and litter size: four pregnant females out of nine, and 2 to 4 kittens per litter. Ultrasonography proved thus to allow the monitoring of follicular growth in the female cat, with low correlation with behavior and vaginal smear modifications. Further studies are needed to evaluate the interest of an ultrasonographic ovarian follow-up to determine the optimal moment for ovulation induction prior to artificial insemination.  相似文献   
15.
The goal of this study was to evaluate the relation between kittens' birth weights and biometrical factors from the kittens and the mother during pregnancy. Knowing fetal birth weight could help in detecting abnormalities before parturition. A Caesarean-section or a postnatal management plan could be scheduled. Consequently, the neonatal mortality rate should be decreased. We used ultrasonographic measurements of femur length (FL) or fetal biparietal diameter (BPD), pregnancies, and maternal factors to obtain a model of prediction. For this purpose, linear mixed-effects models were used because of random effects (several fetuses for one queen and a few paired measurements) and fixed effects (litter size, pregnancy rank, weight, wither height, and age of the queen). This study was performed in 24 purebred queens with normal pregnancies and normal body conditions. Queens were scanned in the second half of pregnancy, using a micro-convex probe. They gave birth to 140 healthy kittens whose mean birth weight was 104 g (ranged 65 to 165 g). No correlation between the birth weight and the age of the queen, as a maternal factor alone, was observed. But the birth weight was found to be inversely proportional to the pregnancy rank and the litter size. Moreover, birth weight increased when the weight and wither height of queen increased. BPD and FL increased linearly during pregnancy so a model was used to estimate mean birth weight. Using this model, we found a correlation between mean birth weights and an association of parameters: maternal factors (wither height and age), and litter size.  相似文献   
16.
Limited evidence is available as to whether Kampo medicine modifies gastrointestinal function in humans. We investigated the effect of a Kampo medicine, Hange-koboku-to (Banxia-houpo-tang, HKT), on patients with functional dyspepsia (FD) and on healthy volunteers with regard to gastric motility. The gastric emptying rate (GER) in FD patients was significantly lower than in the healthy subjects. GER in FD patients and in healthy volunteers showed a significant increase after 2 weeks of medication with HKT. Furthermore, gastrointestinal symptoms improved significantly in the FD patients after the administration of HKT. These results suggest that HKT improves delayed gastric emptying and acts as a prokinetic agent.  相似文献   
17.
目的:评价用B超测量足月胎儿各生理参数来评估胎儿宫内生长的准确性与真实性。方法:414例住院分娩的足月头位单胎孕妇在分娩前4天内超声测量胎儿的双顶径(BPD),枕额径(OFD),枕额周径(HC),腹围(AC),腹横径(ATD),股骨长度(FL)每个参数测量2次,取平均值。出生后24小时内测量新生儿各相应生理参数。用SAS软件进行统计学分析,结果 表明胎儿及新生儿各生理参数均呈正态分布。超声测量的BPD,OFD,HC,AC,ATD,FL与实际测量的结果均有一定相关性。计算二组数据的相关系数,分别为0.710,0.370,0.587,0.698,0.635,0.826。其中BPD,AC,FL相关性较好。结论 临床可选用双顶径,腹围,股骨长等参数来评价胎儿宫内生长发育及推算胎儿体重。  相似文献   
18.
Background and objective: Cytokines have an important role in the pathogenesis of rheumatoid arthritis (RA). Although plasma levels of IL-6 have been related to musculoskeletal ultrasound (MSUS) synovitis in early DMARD-naïve RA, there are no similar studies in established disease. Methods: 64 RA patients treated with non-biological DMARDs and 30 healthy controls were included in this prospective cross-sectional study. A blood sample was taken before evaluation of disease activity (DAS28) and ultrasonography (all tests performed in a blinded fashion). MSUS was performed by one of two ultrasound-trained rheumatologists on 10 joints of both hands. Gray scale (GS) and pD (power Doppler) synovitis were evaluated using a semi-quantitative scale (0–3) in individual joints, and their sum (score 10) was calculated. Plasma cytokines (IL-2, IL-4, IL-6, IL-10, IL-17, TNF, IFN-γ, and VEGF) were quantified by flow cytometry. Results: Levels of all cytokines, excepting VEGF, were significantly higher in RA patients than in controls (P  0.05). In RA patients, IL-6, but not other cytokines, correlated positively with DAS28 and swollen joint count (P  0.01), as well as with 10-joint pD score, and GS and pD of both wrists (P < 0.01 for all tests). In multiple linear regression, the association of IL-6 with 10-joint pD score was maintained even after adjustment for DAS28. However, there was no correlation of IL-6 with tender joint count, 10-joint GS score, or presence of erosions. Conclusion: We demonstrated an association of inflammatory findings on MSUS and plasma IL-6 independently of DAS28 in established RA.  相似文献   
19.
Geometric and tendon excursion methods have both been used extensively for estimating plantarflexor muscle moment arm in vivo. Geometric measures often utilize magnetic resonance imaging, which can be costly and impractical for many investigations. Estimating moment arm from tendon excursion measured with ultrasonography may provide a cost-effective alternative to geometric measures of moment arm, but how well such measures represent geometry-based moment arms remains in question. The purpose of this study was to determine whether moment arms from tendon excursion can serve as a surrogate for moment arms measured geometrically. Magnetic resonance and ultrasound imaging were performed on 19 young male subjects to quantify plantarflexor moment arm based on geometric and tendon excursion paradigms, respectively. These measurements were weakly correlated that approached statistical significance (R2 = 0.21, p = 0.052), and moment arm from tendon excursion under-approximated geometric moment arm by nearly 40% (p < 0.001). This weak correlation between methods is at odds with a prior report (N = 9) of a strong correlation (R2 = 0.94) in a similar study. Therefore, we performed 92,378 regression analyses (19 choose 9) to determine if such a strong correlation existed in our study population. We found that certain sub-populations of the current study generated similarly strong coefficients of determination (R2 = 0.92), but 84% of all analyses revealed no correlation (p > 0.05). Our results suggest that the moment arms from musculoskeletal geometry cannot be otherwise obtained by simply scaling moment arms estimated from tendon excursion.  相似文献   
20.
《Reproductive biology》2023,23(3):100786
Serum inhibin B (INHB) concentrations are associated with testicular volumes (TV) in all periods of childhood. The aim of the study was to investigate the relationship between TV measured by ultrasonography (US) and cord blood inhibin B and total testosterone (TT) concentrations, stratified by mode of delivery. In total 90 male infants were included. Testes of healthy, term newborns were evaluated by US on the third day after delivery. TV were calculated using two formulae: The ellipsoid formula [length (mm) × width (mm2) × π/6] and Lambert formula [length (mm) x width (mm) x height (mm) x 0.71]. Cord blood was taken for the determination of total testosterone (TT) and INHB. TT and INHB concentrations were evaluated according to TV percentiles (<10th, 10th-90th, >90th). There was a strong positive correlation between mean TV calculated with both formulae by percentile group (r = 0.777, r = 0.804, r = 0.846; p < 0.001). Cord blood INHB, but not TT were significantly lower in newborns with TV < 10th percentile compared to those with TV between 10 and 90th percentile and > 90th percentile (p < 0.05). There was a positive correlation between left and right TV calculated by either formula, and cord blood INHB (r = 0.212, 0.313, 0.320, 0.246, p < 0.05), not TT. There was no significant difference between hormones and TV when grouped by mode of delivery (p > 0.05). The Lambert and ellipsoid formulas are equally reliable in calculating neonatal testicular by ultrasound. INHB concentration is high in cord blood and positively correlated with neonatal TV. Cord blood INHB concentration may be an indicator for early detection of testicular structure and function disorders in neonates.  相似文献   
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