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11.
目的 从声学角度客观地检测京剧的嗓音特征 ,为京剧演唱者嗓音的训练和保护提供参考。方法 对 73名 1 6~ 5 7岁不同行当的专业京剧演员或学员 ,利用Dr Speech计算机频谱分析系统对元音 /a/、/i/歌唱舒适音和唱段进行声学参数的检测和分析。结果 各行当元音 /a/、/i/歌唱舒适音的基频 (fundamentalfrequency,F0 )分别是 :丑角 (2 72 6± 42 0 )Hz( x±s ,下同 )、(30 4 2± 2 2 1 )Hz;小生 (499 3± 34 0 )Hz,(485 4± 1 8 7)Hz;老生 (335 6± 6 0 0 )Hz,(31 7 9± 45 1 )Hz ;花脸 (31 9 0±6 1 3)Hz,(34 0 1± 6 8 8)Hz;老旦 (42 7 6± 47 2 )Hz,(437 7± 45 8)Hz ;花旦 (5 35 8± 48 8)Hz,(5 6 1 6± 2 9 2 )Hz ;青衣 (5 48 0± 6 9 5 )Hz,(5 43 5± 79 3)Hz;其它声学参数 :频率微扰 (pitchperiodperturbation,或Jitter)、振幅微扰 (amplitudeperturbation ,或Shimmer)和声门噪声能量 (也称标准化噪声能量级 ,normalizednoiseenergy ,NNE)均在软件提供的正常值范围内 ;京剧演员歌唱音域的跨度为 1 7~ 2 8个八度 ,最低音和多数最高音均比西洋唱法的高音声部相应的值高。结论 京剧嗓音有着独特的声学特征 ;结果对其嗓音的训练和保护有一定的临床参考  相似文献   
12.
Skin expansion in burn patients can be a useful method for secondary skin resurfacing, scar revision or facial remodelling. However, complications and problems occur more often in these patients than in any other. In this paper the incidence of complication in the first and second stages of expansion will be presented. Several rules will then be stated and we will clarify the indications for skin expansion in the treatment of hypertrophic scars, contractures, and post-burn destructions.Lecture given at the first State of the art course on burn reconstruction — Milano, May 1994  相似文献   
13.
Summary To evaluate whether knowledge of plasma levels of anti-epileptic drugs has an effect on therapeutic outcome, 127 epileptic outpatients were randomly assigned to two groups (A and B). Plasma levels of group A were reported to the treating physician who attempted to keep the plasma levels within the therapeutic range. The treating physician was not informed of the results of plasma lavel determinations of group B. Data from 105 patients were available for assessment at the end of the study year. Therapeutic results of groups A and B were not significantly different. The reduction in seizure frequency was associated with an increase in plasma concentrations of the anti-epileptic drugs. Thus, under the conditions of the study, knowledge of plasma levels of anti-epileptic drugs did not further improve therapeutic results.
Zusammenfassung Um festzustellen, ob die Kenntnis des Plasmaspiegels der Antiepileptika das Therapieergebnis verbessern kann, wurden 127 ambulant behandelte Patienten mit Epilepsie in randomisierter Reihenfolge in zwei Gruppen eingeteilt (A und B). Die Plasmaspiegel der Antiepileptika in Gruppe A wurden dem behandelnden Arzt mitgeteilt, der versuchen sollte, die Plasmaspiegel in den Therapeutischen Bereich zu bringen. Die Ergebnisse der Plasmaspiegelbestimmung in Gruppe B (Kontrollgruppe) wurden dem behandelnden Arzt nicht mitgeteilt. Am Ende des Untersuchungsjahres konnten die Daten von 105 Patienten ausgewertet werden. Das Behandlungsergebnis von Gruppe A und von Gruppe B war am Ende des Beobachtungsjahres nicht signifikant verschieden. Die Abnahme der Anfallshäufigkeit ging mit einem Anstieg der Plasmakonzentration der Antiepileptika einher. Somit konnte unter den Bedingungen dieser Studie das Therapieergebnis durch die Kenntnis der Plasmaspiegel der Antiepileptika nicht weiter verbessert werden.
  相似文献   
14.
The TRAM flap has become the gold standard in breast reconstruction but suffers from the disadvantages of poor color match, different texture, and impaired sensation compared to the normal breast. This study reports on a two-stage procedure to address these problems. The first stage consists of insertion of a tissue expander and surgical delay of the TRAM flap. The second stage consists of removal of the tissue expander and transposition of a deepithelized TRAM flap into the tissue expanded cavity. (The capsule is excised.) Four cases of breast reconstruction are reported. The advantage of this procedure is that it offers the benefits of tissue expansion, viz., normal color match, texture, and sensation, and in addition, reconstruction is achieved with autologous tissue by a pedicled TRAM flap. The vascularity of the TRAM is enhanced by a surgical delay procedure.  相似文献   
15.
In severe vaginal malformations, when the distance between the upper vaginal pouch and perineum is too long (6 cm or more), reconstruction of the vagina can be performed by colonic interposition or by long cutaneous flaps obtained by the tissue expansion technique. Two female adolescents were treated using expanded labial skin flaps. Dissection and anastomosis between the vaginal remnant and cutaneous tube was performed by the transtrigonal approach. Results were satisfactory at 2.5-year follow-up. In our opinion, expanded labial skin-flap vaginoplasty has three main advantages: (1) it permits the construction of a large, soft, well-vascularized neovagina using non-hair-bearing labial skin; (2) it obviates postoperative dilations and prevents delayed strictures; and (3) a transtrigonal approach permits an easy vaginal dissection and a careful, tension-free anastomosis.  相似文献   
16.
Assessment of patellar maltracking using combined static and dynamic MRI   总被引:7,自引:0,他引:7  
Between January 1995 and Jul 1997, 474 patients with anterior knee pain resistant to conservative treatment were referred for MR of the knee. The MR examination consisted of routine sequences with an additional patellofemoral dynamic examination using a technique that has been developed at this institution. The dynamic study examines both knees simultaneously, with the patient supine and the quadriceps loaded. No gating or restraint apparatus is needed. Patellar subluxation or tilt was present in 188(40 %) of cases, bilateral in 104 and unilateral in 84 cases (right 39, left 45). It was classified as mild in 51 %, moderate in 39 % and severe in 10 %. Subluxation was more prevalent in females than males (42 % vs. 37 %) and this was most obvious in the severe group where 68 % were female. In 90 knees selected at random, four measurements of patellofemoral morphology were obtained using reconstructed images from a volume gradient echo sequence. These measurements were correlated with the degree of subluxation or tilt. A tibial tubercle distance greater than 20 mm, a femoral sulcus angle greater than 150 degrees, sulcus depth less than 4 mm were specific for subluxation but no measurement proved to be sufficiently sensitive to preclude a tracking study. MRI can be used to define more precisely the anatomy of the extensor mechanism and its relationship to the femur and tibia, in both a static and dynamic setting. In this way, patients with anterior knee pain can be classified more accurately and the outcomes of treatment more reliably assessed. Received: 17 September 1999; Revised: 31 January 2000; Accepted: 4 February 2000  相似文献   
17.
目的建立豚鼠血液流变学各指标的正常参考范围,供学者及同行作研究或实验时参考。方法用心脏采血法采集豚鼠血液5ml、肝素抗凝,雄性44只、雌性23只;用MVIS-2020全自动血液流变学分析仪检测豚鼠血液流变学各指标。结果豚鼠全血黏度(高切)正常值:雄性(5.17±0.72)mpas,雌性(4.86±0.69)mpas;全血黏度(低切):雄性(10.37±1.59)mpas,雌性(9.34±1.38)mpas;血浆黏度:雄性(1.42±0.15)mpas,雌性(1.40±0.13)mpas;全血还原黏度:雄性(6.28±0.90)mpas,雌性(5.93±0.88)mpas;红细胞压积:雄性0.42±0.03,雌性0.37±0.02。结论动物种系之间血液流变学指标存在差异;豚鼠血液流变学结果与性别有关。  相似文献   
18.
目的:观察天然骨缝牵张成骨过程中组织和细胞超微结构的变化。方法:对牵张成骨的缝区组织经过系列处理,进行超薄切片、透射电镜观察。结果:间充质细胞在牵引早期大量增生,并不断分化为成纤维细胞和成骨细胞,后2种细胞的超微结构显示出具有活跃的合成和分泌功能。1周标本成纤维细胞沿牵引力的长轴方向排列,胞核增大,在其周围包绕着发达并扩张的内质网系统;3周标本大量增生活跃的成骨细胞和成纤维细胞,成骨细胞核仁增大、粗面内质网扩张、核糖体丰富、线粒体增多、富含紧密排列的嵴;5、8周标本中骨细胞形成并发育成熟,骨基质逐渐矿化,清晰可见新形成的胶原纤维、哈氏管,以及骨基质矿化的过程。结论:三维牵张过程中,成纤维细胞、成骨细胞活跃,缝区形成新骨。  相似文献   
19.
The purpose of this work was to study the possibility of neutralizing high-calcium fly ash expansion during hydration. The object of the study was the fly ash of Berezovskaya GRES, which is capable of independent setting and hardening. The test in the Le Chatelier molds showed that the divergence of indicator arms was 90–100 mm 1 day after mixing with water. The expansion and cracking of the fly ash could be completely prevented by silica fume addition in an amount of 42.9% by weight of the fly ash. At the same time, the compressive strength of specimens from the fly ash–sand paste in a ratio of 1:5 at the age of 28 days was 1.47 MPa. The isothermal heat release at a temperature of 20 °C for 10 days reached 500 kJ/kg. XRF and DTA results showed that free lime in the fly ash was completely hydrated in 11 days and gave the greatest expansion in the absence of silica fume. The presence of silica fume made the lime hydration incomplete and decreased the expansion. Unslaked free lime remained in the system. Exothermic data showed that silica fume inhibited CaO hydration from the reaction start.  相似文献   
20.
Recycled rubber waste (RW) is produced at an alarming rate due to the deposition of 1.5 billion scrap tires annually around the globe, which causes serious threats to the environment due to its open land filling issues. This study investigates the potential application of RW in concrete structures for mitigating the alkali–silica reaction (ASR). Various proportions of RW (5%, 10%, 15%, 20%, and 25%) partially replaced the used aggregates. RW was procured from a local rubber recycling unit. Cubes, prisms, and mortar bar specimens were prepared using a mixture design recommended by ASTM C1260 and tested for evaluating the compressive and flexural strengths and expansion in an ASR conducive environment for specimens incorporating RW. It was observed that the compressive and flexural strength decreased for specimens incorporating RW compared to that of the control specimens without RW. For example, an 18% and an 8% decrease in compressive and flexural strengths, respectively, were observed for specimens with 5% of RW by aggregates volume at 28 days. Mortar bar specimens without RW showed an expansion of 0.23% and 0.28% at 14 and 28 days, respectively, indicating the potential ASR reactivity in accordance with ASTM C1260. A decrease in expansion was observed for mixtures incorporating RW. Specimens incorporating 20% of RW by aggregate volume showed expansions of 0.17% at 28 days, within the limit specified by ASTM C1260. Moreover, specimens incorporating RW showed a lower reduction in compressive and flexural strengths under an ASR conducive environment compared to that of the control specimen without RW. Micro-structural analysis also showed significant micro-cracking for specimens without RW due to ASR. However, no surface cracks were observed for specimens incorporating RW. It can be argued that the use of RW in the construction industry assists in reducing the landfill depositing issues with the additional benefit of limiting the ASR expansion.  相似文献   
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