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101.
102.
This investigation used a derivation of acoustic reflection (AR) technology to make cross-sectional measurements of changes due to aging in the oral and pharyngeal lumina of male and female speakers. The purpose of the study was to establish preliminary normative data for such changes and to obtain acoustic measurements of changes due to aging in the formant frequencies of selected spoken vowels and their long-term average spectra (LTAS) analysis. Thirty-eight young men and women and 38 elderly men and women were involved in the study. The oral and pharyngeal lumina of the participants were measured with AR technology, and their formant frequencies were analyzed using the Kay Elemetrics Computerized Speech Lab. The findings have delineated specific and similar patterns of aging changes in human vocal tract configurations in speakers of both genders. Namely, the oral cavity length and volume of elderly speakers increased significantly compared to their young cohorts. The total vocal tract volume of elderly speakers also showed a significant increment, whereas the total vocal tract length of elderly speakers did not differ significantly from their young cohorts. Elderly speakers of both genders also showed similar patterns of acoustic changes of speech production, that is, consistent lowering of formant frequencies (especially F1) across selected vowel productions. Although new research models are still needed to succinctly account for the speech acoustic changes of the elderly, especially for their specific patterns of human vocal tract dimensional changes, this study has innovatively applied the noninvasive and cost-effective AR technology to monitor age-related human oral and pharyngeal lumina changes that have direct consequences for speech production. 相似文献
103.
目的 用高效液相色谱法(HPLC法)测定去氧氟尿苷的含量及其有关物质。方法 采用Diamonsil C—粒(250mm×4.6mm,5μm),流动相为乙腈-水(1:1),检测波长为269nm,流速为0.8mL/min。结果 去氧氟尿苷质量浓度在10.0~200.4μg/mL范围内与峰面积线性关系良好,r:0.9999(n:5),平均回收率为100.2%,RSD=0.14%。结论 HPLC法简便、准确,专属性好,灵敏度高,可用于去氧氟尿苷含量及有关物质的测定。 相似文献
104.
处于青春期的青少年男女普遍进入一种试图发现、选择和试探自己的性心理需求对象的“寻梦”状态。在很长的一段时间里,“寻梦”双方的接触和亲近,具有未专一、不稳定、易更换的特点。这说明,交异性朋友不一定就产生爱情,而是泛指和不同性别的朋友来往,发展普通的友谊关系。从发展心理学角度看,交异性朋友是必要的和有益的,但应该受到理性约束。在校学生应该避免过早恋爱。 相似文献
105.
Objective:To evaluate the feasibility and safety of prenatal diagnosis by traneabdominal chorionic villus sam-pling(TA-CVS)via the guidance of B-mode ultrasound in the first trimester of gestation.To explore the technique of long time culture and chromosome preparation of villi in early pregnancy.To evaluate the feasibility of the above techniques in the application of the prenatal cytogenetic diagnosis.Methods:One hundred and thirty-five singleton pregnancies at risk were referred from January 2001 to Decem-ber 2007.Results:The average maternal age was 35.2 years.TA-CVS was performed in the 10~13th weeks of gestation and the average gestational age was 10.89 weeks.All attempts at sampling were successful.The rate of operation-associated fetal loss was 0.74%.The failure rate of prenatal diagnosis because of inadequate amount of specimen was 0.The average culture time was 5-7 days.The success rate of the cell culture was 98.5%.No maternal con-temination and bacterial contamination happened.Fifteen cases of abnormal karyotype and one case of confined pla-cantel mosaiciem were diagnosed.Conclusion:TA-CVS appears to be safe and feasible and might to be offered in the prenatal diagnosis in the first trimester of gestation.The technique of long time culture and chromosome preparation of villi is stable and reliable.It is feasible to apply these techniques in the clinical practice of prenatal cytogenetic diagnose in the early pregnancy. 相似文献
106.
107.
Objective To observe the effect of pulmonary circulation by 6% hydroxyethyl starch 130/0.4 during induction period from epidural block combined with general anesthesia. Methods Twenty-six hepatobiliary surgical patients with ASA Ⅰ-Ⅱ, aged 32 y-59 y, weighing 54 kg-73 kg, were randomized into 2 groups(n=13): hydroxyethyl starch 130/0.4 group(HS)and complex acetic acid Ringer's solution (RL). Above-mentioned solutions were infused 7 ml/kg respectively before induction. The pulmonary circulation hemodynamic parameters such as pulmonary arterial systolic pressure (PASP), pulmonary arterial diastolic pressure (PADP), mean pulmonary artery pressure(MPAP), pulmonary artery wedge pressure(PAWP), pulmonary vascular resistance(PVR) and right ventricular stroke work(RVSW) were recorded at base value(T0), 10 min after infusion(T1), 5 min after induction(T2), 5 rain after intubation(T3), 10 rain after intubation(T4)and 20 min after intubation(T5). Results PASP、PADP、MPAP、PAWP and CVP were significantly higher in group HS at T, than the values at T0 (P<0.05); PVR in group HS was obviously lower from T1 to T5 than the value at To (P<0.05 or P<0.01); RVSW was significantly higher in two groups at T1 than base value (P<0.05), but that in group HS was lower than base value (P<0.05 or P<0.01); HR obviously decreased in two groups from T2 to T5 as compared with the value at T0 (P<0.05); MAP was lower from T3 to T5 than the value at To (P<0.05 or P<0.01). PVR was obviously lower in group HS from T1 to T5 than that in group RL (P<0.05 or P<0.01); MAP obviously increased from T2 to T5 in group HS as compared with the value in group RL(P<0.05 or P<0.01). Conclusion 6% hydroxyethyl starch 130/0.4 can obviously reduce PVR during induction pe-riod from epidural block combined with general anesthesia. In all, there is no effect on pulmonary circulation by 6% hydroxyethyl starch 130/0.4. 相似文献
108.
Millicent Ford Rauch Sara Royce Hynes James Bertram y Redmond Rebecca Robinson Cicely Williams Hao Xu Joseph A. Madri Erin B. Lavik 《The European journal of neuroscience》2009,29(1):132-145
Angiogenesis precedes recovery following spinal cord injury and its extent correlates with neural regeneration, suggesting that angiogenesis may play a role in repair. An important precondition for studying the role of angiogenesis is the ability to induce it in a controlled manner. Previously, we showed that a coculture of endothelial cells (ECs) and neural progenitor cells (NPCs) promoted the formation of stable tubes in vitro and stable, functional vascular networks in vivo in a subcutaneous model. We sought to test whether a similar coculture would lead to the formation of stable functional vessels in the spinal cord following injury. We created microvascular networks in a biodegradable two-component implant system and tested the ability of the coculture or controls (lesion control, implant alone, implant + ECs or implant + NPCs) to promote angiogenesis in a rat hemisection model of spinal cord injury. The coculture implant led to a fourfold increase in functional vessels compared with the lesion control, implant alone or implant + NPCs groups and a twofold increase in functional vessels over the implant + ECs group. Furthermore, half of the vessels in the coculture implant exhibited positive staining for the endothelial barrier antigen, a marker for the formation of the blood–spinal cord barrier. No other groups have shown positive staining for the blood–spinal cord barrier in the injury epicenter. This work provides a novel method to induce angiogenesis following spinal cord injury and a foundation for studying its role in repair. 相似文献
109.
ZENG Rong HU Zi-bing GUO Wei-tao LIN Hao SUN Xin WEI Jin-song WU Shao-ke 《中华创伤杂志(英文版)》2007,12(1):167-172
To explore the electrophysiological proper-ties of differentiation of rat bone marrow-derived stromal stem cells (rBMSCs) to neuron-like cells in vitro by edaravone, a new type of free radical scavenger. Methods: Stromal stem cells were separated from rat bone marrow with Ficoll-Paque reagent and expanded in different culture medium in vitro, rBMSCs were induced by edaravone containing serum-free L-DMEM. Morphologic observation and Western blot analysis including the ex-pression of Nav1.6, Kv1.2, Kv1.3, Cav1.2 were performed, and whole patch-clamp technique was used. Results: Cyton contraction and long processes were shown in differentiated stromal stem cells. Nav1.6, Kv1.2, Kv1.3 and Cav1.2 were expressed in both differentiated and undifferentiated cells. However, the expression of channel proteins in differentiated cells was up-regulated. Consistently, their resting potential and outward currents were also enhanced in the differentiated cells, which was especially significant in the outward rectifier potassium current. Conclusion: In vitro, neuron-like cells derived from rBMSCs, induced by edaravone, possess electrophysiologi-cal properties of neurons. 相似文献
110.
目的 通过监测脑血流速度、颈静脉球部血氧饱和度(SjvO2)、血压、心率(HR)和不良反应发生率等,综合评价艾司洛尔用于控制开颅手术苏醒期患者脑过度灌注的效果.方法 选择择期在全身麻醉下行开颅肿瘤切除术的患者,随机分为艾司洛尔组(E组,20例)和对照组(C组,20例).E组患者从拔管即刻起给予艾司洛尔0.6 mg·kg1·h-1静脉持续滴注15 min C组患者从拔管即刻起给予0.9%氯化钠溶液静脉持续滴注.分别监测两组患者术前、术后拔管即刻及拔管后15、30、45、60 min时的大脑中动脉平均血流速度(MCAVm)、SivO2平均动脉压(MAP)及HR,并记录不良反应发生例数.结果 E组术后15和30 min的MCA Vm、sjvO2及HR均显著低于C组(P值均<0.01),术后15 Min的MAP显著低于C组(P<0.05).无一例患者发生与艾司洛尔相关的药物不良反应.结论 艾司洛尔是控制术后脑过度灌注的理想药物. 相似文献