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91.
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
92.
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
93.
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
94.
95.
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
96.
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
97.
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
98.
腹腔镜与开腹手术治疗子宫内膜癌的临床对比分析——前瞻性随机对照研究 总被引:7,自引:4,他引:3
目的 探讨腹腔镜手术治疗子宫内膜癌的临床效果.方法 将1998年8月~2004年12月术前确诊为子宫内膜癌的患者60例分为2组,分别施以腹腔镜下及腹式广泛子宫切除,术中根据子宫肌层受侵情况决定是否行盆腔淋巴结清扫术,前瞻性研究两组围手术期及生存情况.结果 与开腹组比较,腹腔镜组手术时间长[(247.8±77.8)min vs(196.6±63.7)min,t=2.789,P=0.007],术中出血量相近[(265.0±187.6)ml vs(350.0±210.9)ml,t=-1.649,P=0.104],切除盆腔淋巴结数量相近[(22.0±5.0)个vs(22.8±5.2)个,t=-0.607,P=0.546],术后并发症发生率差异无显著性(10/30 vs15/30,χ2=1.714,P=0.190),术后肛门排气时间早[(44.3±11.1)min vs(55.2±12.8)min,t=-3.524,P=0.000],住院时间短[(8.7±3.2)d vs(10.2±2.0)d,t=-2.177,P=0.034].腹腔镜组随访(28.6±17.4)月,均无瘤存活;开腹组随访(28.9±16.6)月,3例因转移或复发死亡.结论 腹腔镜手术可达到与开腹手术一样的效果,可以作为治疗子宫内膜癌的术式之一,但应在有条件的医院逐步开展. 相似文献
99.
Hp相关胃炎患者血清表皮生长因子(ECG)和β2—微球蛋白(β2—MG)水平研究 总被引:1,自引:0,他引:1
目的探索EGF和β2-MG在CSG -CAG -GC演变模式中的变化规律 ,探讨Hp对EGF和β2-MG有无影响。方法应用尿素酶试验法、血清学试验法和组织学诊断法 ,进行Hp检查 ,应用放射免疫法检测血清EGF及β2-MG水平。结果(一)EGF水平(μg/L) :(1)按CSG -CAG -GC逐渐升高 ,依次为0.3229±0.225 ,0.8823±0.2549,1.3999±0.8935,GC组高于CSG组 (P<0.01) ,也高于CAG组 (P<0.05) ,CAG组高于CSG组 (P<0.01)。(2)CSG患者Hp(+)组 (0.2404±0.1103)低于Hp( -)组 (0 .4492±0.2931) (P<0.01) ;CAG患者Hp(+)组 (0 .8119±0.279)低于Hp(- )组(1.0056±0.1704) ,GC患者Hp(+)组 (1.159±0 .9229)低于Hp(- )组(1 .4963±0 .9127) ,均无统计学差异 (P>0.05)。(二 ) β2-MG水平 (mg/l) :(1)按CSG -CAG -GC顺序增高 ,依次为 :1.659±0.4321 ,1 .9661±1 .0802,2.3431±0 .5951 ,GC组高于CSG组 (P<0.01),CAG组高于CSG组 ,GC组高于CAG组 ,均无统计学意义 (P>0.05)。(2)同一胃病Hp( +)组与Hp( -)组比较血清β2-MG水平均无明显差异 (P>0.05)。结论按CSG -CAG -GC ,EGF水平逐渐升高 ,β2-MG有此种趋势。Hp有降低EGF的作用 ,Hp对β2-MG水平无明显影响 相似文献
100.
33例肝占位性病变MRI误诊的分析 总被引:1,自引:0,他引:1
我院1988年以来4000余例腹部MRI中,发现肝占位性病变误诊33例。所用机型为美国Disonics公司0.5T超导MRI,自旋回波序列(SE序列)、常规T1加权(T1WI)、质子加权(PDWI)、T2加权(T2WI),覆盖全肝。其中,PHC误诊为MHC5例、MHC误诊为PHC6例、PHC误为HHE5例、MHC误诊为HHE2例、HHE误诊为PHC6例、肝硬化结节误诊为PHC2例、炎性假瘤误诊为PHC3例、肝结核误诊为PHC1例、HCY误诊为HHE3例。本文从病变的影像学特征和扫描技术方面详细探讨了误诊的原因和鉴别诊断要点。 相似文献