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101.
目的 探讨老年人急性阑尾炎的临床特点,更好地把握腹腔镜阑尾切除(LA)术的方法和特点。方法 回顾分析50例老年人急性阑尾炎LA的临床资料。结果 LA均获成功,患者全部治愈,无严重的并发症发生,肠功能恢复时间及住院时间均缩短。结论 老年人反应迟钝,阑尾炎进展快,易发生坏疽及穿孔,合并症多,手术风险较高,LA是安全、可行的,除个别腹膜后阑尾炎外,其余均可施行LA。 相似文献
102.
目的:基于累及头颈部淋巴组织病变的临床不典型性,旨在探讨MRI对其进行鉴别诊断的客观依据。方法:对本组22例可疑累及头颈部淋巴组织的各类病变进行MRI检查并与病理学结果进行对照。结果:MRI对本组22例累及淋巴组织病变的诊断与病理学诊断的符合率(21/22)约为95%。结论:MRI是对累及头颈部淋巴组织病变的重要检查手段,并能为明确其诊断提供客观依据。 相似文献
103.
104.
The systolic hump in the aortic blood pressure wave is defined as the aorticresistance component proportional to the aortic
blood flow superimposed on the windkessel component. An electrical analogue comprising a series resistance (aortic resistance)
plus a resistance (peripheral resistance) and capacitance (aortic compliance) in parallel (i.e. windkessel component) is used
for analysis. Curve fitting using the leastsquares method is performed on calculated and measured blood pressure waves from
dogs under haemodynamical conditions induced by infusion of three drugs (noradrenaline, isoproterenol and acetylcholine).
The curve fitting RMS (root mean square) errors are <3% for blood pressure waves and <30% for blood flow waves, with good
agreement between measured and calculated blood flow waveforms. Infusion of noradrenaline and acetylcholine is found to induce
a significant decrease and increase in the aortic resistance, respectively. Although only a small fraction of the blood pressure
wave, the systolic hump has a marked effect on the systolic pressure waveform. 相似文献
105.
David W. Farley DDS John D. Jones DDS Robert J. Cronin DDS MS 《Journal of prosthodontics》1998,7(2):84-90
Phonetics, esthetics, function, and comfort form the foundation of a successful dental prosthesis. A review of the mechanics of speech as well as common speech problems encountered with a removable maxillary prosthesis are presented. The use of a palatogram to aid the clinician in the assessment and resolution of speech problems associated with a maxillary denture is demonstrated. 相似文献
106.
碱性成纤维细胞生长因子(bFGF)加速猪背部创伤修复的实验研究 总被引:30,自引:0,他引:30
实验采用猪背部创伤模型,观察重组的碱性成纤维细胞生长因子(bFGF)对创伤修复的作用。在无菌条件下用特制打孔器在猪背部切割皮肤,形成2.5cm2的园型创面。将150个创面分成5组,分别以bFGF(60u/cm2创面),bFGF((60u/cm2创面)加SD-Ag、SD-Ag、生理盐水以及不治疗等方法处理,每间隔一天换药一次。实验结果表明,bFGF具有显著促进肉芽组织生长、加速创面再上皮化率以及增加创面愈合组织抗张力强度等作用。FGF显著促修复效应的确切机制尚不完全清楚,可能包括直接与间接效应两方面。 相似文献
107.
Abstract: The use of neuromuscular electrical stimulation (NMES) for rehabilitation of gait in spinal patients is widely known. The best results can be obtained with the use of biomechanical sensors and a closed loop NMES system. One of the biggest problems faced in the design of control systems for closed-loop operation, in gait rehabilitation, is the variation of the mechanical conditions during the phases of gait. This work presents a new approach to ease the design of rule-based closed loop systems for operation in conditions such as gait rehabilitation. 相似文献
108.
胫骨延长术是矫治小儿麻痹后遗症下肢短缩最常见的术式,但如何恢复或改善术后的功能,目前尚无一套系统的程序。本文作者根据自行设计的胫骨延长休后功能康复的临床观察,作较系统地介绍,并就该程序的合理性,进行了讨论与论证。 相似文献
109.
Summary— To investigate if the functional alterations observed in resistance arteries of spontaneously hypertensive rats (SHRs) were also present at the coronary level, in vitro experiments were performed in mesenteric resistance arteries (MRA) and in right (RIC) and left interventricular coronary (LIC) arteries taken from 15–25-week-old SHR and age-matched Wistar Kyoto rats WKYs. Using a passive extension protocol, internal diameters corresponding to 100 mmHg intraluminal pressure (D100) were determined and vessels were set up to a normalized internal diameter (0.9 D100). SHR mesenteric resistance arteries had a significantly smaller diameter compared to WKY arteries, whereas both types of SHR coronary arteries had a greater diameter compared to those of WKY rats. In arteries in the absence of contracting agonist, nitro-L-arginine (NOLA, 100 μM) induced a progressive rise in basal tone, which could be reversed by subsequent addition of L-arginine (100 μM) but not D-arginine (100 μM). When expressed as percent of maximal contractions induced by agonists (noradrenaline, NA [10 μM] in MRA; serotonin, 5-HT [10 μM], in RIC and LIC), these contractions were significantly stronger in WKY compared to SHR coronary and mesenteric resistance arteries. In NA-precontracted MRA and 5HT-precontracted coronary arteries in the presence of indomethacin (10 μM), the magnitude of acetylcholine-induced maximal relaxations (expressed as percent of maximal contractions induced by agonists) was greater in WKY compared to SHR arteries. After a 30-min incubation period, NOLA (100 μM) completely inhibited relaxations induced by acetylcholine (0.01–10 μM) in all types of precontracted arteries. Subsequent additions of sodium nitroprusside, (SNP, 10 μM) induced complete relaxations in all preparations. These results show that a basal release of NO or NO-like compound by endothelial cells is present in isolated mesenteric resistance and coronary arteries of WKY rats and SHRs. The contribution of endothelium-derived relaxing factor-nitric oxide (EDRF-NO) to arterial tone was lower in MRA compared to coronary arteries in both strains and in SHR compared to WKY arteries. In the SHR preparations, the impaired relaxation induced by acetylcholine appeared to be due to a functional alteration of the endothelium in the presence of normal reactivity of the smooth muscle cells. 相似文献
110.
甘草黄酮的提取分离和含量测定 总被引:21,自引:0,他引:21
封士兰 《兰州大学学报(医学版)》1998,(4)
目的:充分利用甘草资源。方法:从提取过甘草酸的废渣中提取甘草黄酮并进行含量测定。结果:用碱酸处理和用大孔树脂处理黄酮含量高,收率也高。结论:从甘草废渣中提取甘草黄酮具有较好的社会效益和经济效益 相似文献