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81.
Cecily V. Bishop Michelle L. Sparman Jessica E. Stanley Alistair Bahar Mary B. Zelinski Richard L. Stouffer 《American journal of primatology》2009,71(5):384-392
To date, ultrasonography of monkey ovaries is rare and typically of low resolution. The objectives of this study were to use state‐of‐the‐art, high‐resolution, transabdominal ultrasonography with real‐time Doppler capabilities to: (1) determine whether one can reliably detect in real time the large dominant follicle, the corpus luteum (CL), and small (<2 mm) antral follicles on the ovaries of rhesus monkeys during the natural menstrual cycle; and (2) predict the follicular response of rhesus ovaries to controlled ovarian stimulation (COS) protocols. Rhesus monkeys were selected for transabdominal ultrasonography using a GE Voluson 730 Expert Doppler System at discrete stages of the menstrual cycle. Subsequently, serial ultrasound scanning was employed to observe growth of antral follicles and the CL. Finally, females were scanned to assess follicular growth during COS. The dominant structure and small antral follicles (<2 mm) were reliably visualized in real time. The follicle destined to ovulate could be identified by size differential by day 3 of the follicular phase. The number of small antral follicles present before onset of COS protocol correlated positively with the number of metaphase II‐stage oocytes collected after treatment. The results of this study demonstrate that the population dynamics of antral follicle pools can be noninvasively evaluated in monkeys during natural and pharmacologic ovarian cycles. Am. J. Primatol. 71:384–392, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
82.
摘要 目的:探讨泌尿系造影联合彩色多普勒对小儿先天性肾积水的诊断价值。方法:选取2018年11月~2021年11月在本院治疗的88例先天性肾积水患儿为研究对象,所有患儿均完善静脉肾盂造影及彩色多普勒超声检查,以病理诊断结果为金标准,对比两种检查方法对小儿先天性肾积水的诊断价值。结果:彩色多普勒超声检查结果显示,肾积水轻度、中度、重度患儿分别为10例、39例、39例,不同病情程度患儿比较,重度组收缩期峰值速度(PSV)、舒张期最小流速(EDV)均低于中度组和轻度组,重度组血流阻力指数(RI)高于中度组和轻度组(P<0.05),但轻度组与中度组PSV、EDV、RI比较差异无统计学意义(P>0.05)。与病理学诊断检查结果对比,彩色多普勒超声对中度、重度先天性肾积水患儿具有较高的诊断效能,其准确度分别为90.91%、93.18%,与病理诊断kappa值分别为0.795、0.862,具有较高的一致性;但对轻度肾积水诊断效能较低,kappa值为0.629,一致性一般。静脉肾盂造影对轻度先天性肾积水患儿具有较高的诊断效能,准确度为96.59%,与病理诊断kappa值为0.824,具有较高的一致性;但对中度、重度肾积水诊断效能较低,kappa值分别为0.583、0.565,一致性一般。彩色多普勒超声联合静脉肾盂造影诊断准确率高达94.32%,明显高于两检查方法单独应用(P<0.05)。结论:不同病情程度的先天性肾积水患儿具有不同超声征象,彩色多普勒超声对中、重度肾积水患儿具有较好的诊断价值,而静脉肾盂造影诊断轻度肾积水患儿的效能较好,将二者联合可提高对先天性肾积水的诊断准确率。 相似文献
83.
Background3D freehand ultrasound enables the creation of volumetric data. The acquisition of morphological features, such as muscle volume, is influenced by the variations in force applied to the skin with the ultrasound probe. To minimise the deformations, a concave-shaped plastic mount combined with a custom-shaped gel pad was developed for the ultrasound head, named Portico. This study analyses to what extent the Portico reduces muscle deformation and corresponding errors in estimating muscle volume.MethodTwenty medial gastrocnemius (MG) muscles were assessed (10 from typically developing children; 10 from children with spastic cerebral palsy). Two repetitions were acquired in each of the following approaches: (1) with the lower leg submerged in a water tank as a non-deformed reference; (2) probe-on-skin (PoS) as the conventional approach and (3) the newly introduced Portico. PoS and Portico data were registered with respect to the ones corresponding in a water tank. An in-house software package (Py3DFreeHandUS) was used to process the data and MG volume was estimated using MeVisLab. The minimal detectable change (MDC) was calculated.ResultsWith respect to the PoS approach, the Portico reduced muscle deformation by 46%. For both the typically developing and spastic cerebral palsy cohorts, lower MDCs were found when using the Portico.DiscussionDespite the improvements, the Portico did not yield statistically more reliable MG volume estimations than the traditional PoS approach. Further improvement can be attained by optimising the fit between the gel pad and the curvature of the limb, using a larger choice of Portico geometries. 相似文献
84.
《Saudi Journal of Biological Sciences》2020,27(7):1722-1725
The value of thyroid scintigraphy in hyperthyroidism diagnosis has long been the subject of debate. Unresolved issue is whether scintigraphy should be performed routinely, selectively, or for all hyperthyroidism patients. So, this study is concerned with the evaluation of thyroid scintigraphy for identifying hyperthyroidism in comparison with thyroid stimulating hormone (TSH) and ultrasound. This is cross sectional study including convenient patients sample (n = 50, 15 males and 35 females) aged (20–50 years) with primary hyperthyroidism and were attending endocrine clinics at King Faisal Specialist Hospital and Research Centre. All patients performed clinical investigations (TSH, ultrasound and thyroid scintigraphy). Among these patients, 96%, 48/50, had positive findings for hyperthyroidism with thyroid SC (95% CI; 96.0–99.5%); 84%, 42/50, had positive findings for hyperthyroidism by US (95% CI; 70.9–92.8%); and 56%, 28/50, had positive findings for hyperthyroidism by TSH measurement (95% CI; 41.3.0–70.0%). There was very good agreement between scintigraphy diagnosis and ultrasonography (kappa score = 0.812 (P < 0.0001), 95% CI (0.77–0.85). In many cases, scintigraphy provides considerably more functioning and anatomic details than ultrasound. In conclusion, these findings bring forth practical aspects of thyroid scintigraphy utilization for hyperthyroidism. By combining functional and anatomical information in one step, scintigraphy provides non-invasive, simple, fast and cost effective hyperthyroidism diagnostic method and has the potential to replace TSH and ultrasonography in hyperthyroidism investigation. 相似文献
85.
86.
目的:探讨女性盆底功能障碍性疾病的相关因素及盆底超声测定压力性尿失禁SUI的临床意义。方法:选取我院2019年-2020年共收治的63例盆底功能障碍性疾病患者作为研究对象,将其分为研究组,另取同期来我院进行体检的63例健康女性作为对照组,对所有女性应用盆底超声检测,对比两组女性静息状态下和Valsalva状态下的盆底超声检查指标,对通过问卷调查方式,调查两组女性的一般临床治疗,对于女性盆底功能障碍性疾病的相关因素进行单因素分析与多因素分析,最终得出盆底肌功能障碍性疾病的相关因素。结果:在静息状态下通过盆底超声发现,研究组与对照组膀胱尿道后角、肛提肌裂孔面积、尿道倾斜度对比差异显著(P<0.05),两组女性膀胱颈位置、膀胱位置对比无明显差异(P>0.05);在Valsalva状态下通过盆底超声发现,研究组与对照组膀胱尿道后角、肛提肌裂孔面积、尿道倾斜度、膀胱颈位置、膀胱位置对比差异显著(P<0.05);两组女性年龄、BMI、孕次、产次、绝经情况以及白带清洁度是否≥Ⅲ度情况对比差异显著(P<0.05),两组女性子宫肌瘤史情况对比无显著差异(P>0.05);logistic回归分析结果显示,年龄、绝经情况、子宫肌瘤史和白带清洁度≥Ⅲ度不是盆底功能障碍性疾病的独立危险因素(P>0.05),BMI、孕次、产次为盆底功能障碍性疾病的独立危险因素(P<0.05)。结论:盆底肌超声在对盆底功能障碍性疾病患者压力性尿失禁的诊断中具有重要价值,在静息状态下和Valsalva状态下发现患者的膀胱经移动情况与尿道倾斜情况。年龄、BMI、孕次、产次、绝经情况以及白带清洁度是否≥Ⅲ度可能与盆底功能障碍性疾病具有一定关系,BMI、孕次、产次为盆底功能障碍性疾病的独立危险因素。 相似文献
87.
Picrorhiza kurrooa Royle ex Benth., a high value medicinal herb of alpine Himalaya and a source of hepatoprotective picrosides, is listed as
‘endangered’ due to heavy collection from its natural habitat. The present report deals with successful propagation of this
species using both conventional and in vitro techniques. Vegetative propagation was achieved by rooting runner cuttings with indole-3-butyric acid (IBA) or α-naphtheleneacetic
acid (NAA) treatment before planting. Nearly 87% rooting success was achieved by treatment of cuttings with 50.0 μM IBA. Seeds were given a presoaking treatment with gibberellic acid (GA3), 6-benzylaminopurine (BAP) or a combination of both to influence germination. More than 11-fold improvement in germination
was recorded in seeds treated with 250.0 μM GA3. In vitro shoot multiplication was achieved through sprouting of axillary buds using nodal segment. Multiple shoots were formed following
culture for 3 weeks on Murashige and Skoog (MS; 1962. Physiologia Plantarum 15: 473–497) medium containing 1.0 μM BAP. Cent
percent rooting success, without basal callus formation, was observed when individual microshoots were placed in MS medium
supplemented with IBA. The plantlets raised using conventional as well as tissue culture methods were hardened and successfully
established in the experimental field located at 2450 m elevation. In addition, strategies have been discussed to encourage
cultivation and in situ conservation of this highly valued medicinal herb so as to reduce pressure on its natural populations. 相似文献
88.
89.
《Chemical Speciation and Bioavailability》2013,25(4):163-173
ABSTRACTTotal aluminum, arsenic, calcium, cadmium, iron, lead, potassium, magnesium, nickel and zinc were determined in black tea by electro thermal atomic absorption spectrometry after ultrasonic assisted pseudo-digestion with mixture of acid and oxidant. All the metals were also determined in the tea infusions in order to know the percentage of each element leached into the liquor. A conventional acid digestion on electric hot plate was used to obtain total metals under study for comparative purpose. Analytical results for Al, As, Ca, Cd, Fe, K, Mg, Ni, Pb and Zn obtained by ultrasound assisted pseudodigestion, and conventional wet digestion methods showed a good agreement, thus indicating the possibility of using ultrasonic assisted digestion sample preparation instead of intensive treatments inherent with the acid digestion methods on electric hot plate. The validity and accuracy of both procedures were checked by using certified sample of NIES No. 7 (Tea Leaves). Non significant differences were observed for P>0.05 when comparing the values obtained by both methods (paired t-test).Principal component analysis (PCA) was applied in order to determine the different amount of metals as main sources of variability in the data sets and to establish the relation between samples (branded and nonbranded tea samples) and micronutrient, trace and toxic metals (variables). Hierarchical cluster analysis (HCA) was used to explore the different branded and nonbranded tea samples grouping according to the essential and toxic metals as additional information to the out put obtained by PCA. 相似文献
90.
Amena Ali Abuzer Ali Abu Tahir Mohammed Afroz Bakht Mohamed Jawed Ahsan 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):135
We reported herein an efficient, environmentally friendly synthesis of hydrazine carboxamides (6a–l) in a water-glycerol (6:4) solvent system using ultrasonic irradiation. Ultrasonicated reactions were found to be much faster and more productive than conventional synthesis. The prepared compounds (6a–l) were tested against nine panels of 60 cancer cell lines according to the National Cancer Institute (NCI US) protocol. N-(4-Chlorophenyl)-2-(2-oxoindolin-3-ylidene)hydrazine-1-carboxamide (6b) was discovered to be promising anticancer agents with higher sensitivity against CCRF-CEM, HOP-92, UO-31, RMPI-8226, HL-60(TB), and MDA-MB-468 with percent growth inhibitions (%GIs) of 143.44, 33.46, 33.21, 33.09, 29.81, and 29.55 respectively. Compounds (6a–l) tested showed greater anticancer activity than Imatinib, except for compound 6k. Compounds 6b and 6c were found to be lethal on the CCRF-CEM leukaemia cell line, with %GIs of 143.44 and 108.91, respectively. Furthermore, molecular docking analysis was performed to investigate ligand binding affinity at the active site of epidermal growth factor (EGFR). 相似文献