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目的:制备银杏内酯B(GB)柔性纳米脂质体,并对其体外透皮规律进行研究。方法:采用薄膜分散法制备银杏内酯B柔性纳米脂质体,并对其形态及粒径大小进行分析;采用改良的 Franz 扩散池进行体外透皮吸收试验,比较银杏内酯B醇溶液、银杏内酯B柔性纳米脂质体及普通银杏内酯B纳米脂质体的经皮累积渗透量及渗透速率。结果:此方法制得的脂质体平均包封率为(89.52±1.76)%,平均粒径为(208.3±25.49) nm,Zata电位为-49.2 mV。柔性纳米脂质体8 h的累积透过量为189.97 μg·cm-2,8 h的渗透速率为23.75 μg·cm-2·h-1。结论:柔性纳米脂质体包封率较高,稳定性良好,可显著促进银杏内酯B的透皮吸收。  相似文献   
3.
目的:了解弹性义齿修复的临床效果,为临床应用提供参考。方法:152例门诊缺牙患者,制作弹性义齿修复体188件,上颌130件,下颌58件。Kennedy一类缺损修复6件,Kennedy二类缺损修复4件,Kennedy三类缺损修复102件,Kennedy四类缺损修复76件。通过1-4年的观察,从形态和功能、固定和稳定、颜色和美观以及对组织保健判断对义齿的满意程度,并进行临床效果评价。结果:79例95件弹性义齿具有良好的美观效果,颜色满意,感觉舒适,满意和较满意率达100%,Kennedy三、四类缺损修复率为94.74%。弹性义齿对Kennedy一类缺损修复的满意和比较满意率为66.67%;对Kennedy二类缺损修复的满意和比较满意率为50.00%;对Kennedy三类缺损修复的满意和比较满意率为96.15%;对Kennedy四类缺损修复的满意和比较满意率为84.21%。结论:(1)弹性义齿是一种美观、舒适、对基牙预备甚少的可摘局部义齿修复形式。(2)弹性义齿较适合咀嚼压力小而缺牙数目不多的前牙和前磨牙缺失的修复。  相似文献   
4.
A 50-year-old woman presented with a 5-year history of mild pain in her right knee, which had increased over the last 2 years. A palpable mass over the anterolateral aspect of the knee was obvious and the last 3 months she was experiencing locking episodes with consequent knee effusion. The differential diagnosis was driven between meniscal cyst, pigmented villonodular synovitis, synovial sarcoma, synovial chondromatosis, and aneurysm. After a diagnostic arthroscopy, the lesion was excised by a limited lateral arthrotomy. The pathologic findings revealed a synovial cyst. Intra-articular synovial cysts are uncommon, nonsymptomatic, and mostly incidental findings on magnetic resonance imaging (MRI) and arthroscopy. This lateral meniscus synovial cyst (2.5 × 2.5 cm) was enlarged within the intracondylar notch and produced disabling knee symptoms. The peculiarity of this lesion was the tumor-like appearance: its large size, the progress of symptoms, and the multilobulated, nonhomogenous signal on the MRI scan. One year postoperatively, the patient is asymptomatic and the MRI obtained at 6 months revealed no remnant of the fully excised cyst.  相似文献   
5.
吸氧对纤维支气管镜检查患者相关血气指标的干预和影响   总被引:1,自引:1,他引:0  
目的:了解中等浓度吸氧在纤维支气管镜(FB)检查中的安全性和价值。方法:在行FB检查人群中随机选择25例,分别观察FB置人气道(置镜)前后及中等浓度吸氧前后患动脉血氧分压(PaO2)、动脉血二氧化碳分压(PaCO2)和血氧饱和度(SpO2)的变化。结果:置镜使患SpO2和Pa02有显下降(P<0.001),而PaCO2差异无显性(P>0.05)。接着吸氧5L/min后,Sp02和PaO2与置镜后比较,有明显提高(P<0.001),而PaCO2变化无统计学意义(P>0.05)。l3例患置镜前和吸氧后PaO2及SpO2比较,差异均具明显显性(P<0.01),而PaCO2无明显变化(P>0.05)。结论:吸中等浓度氧对普通行FB检查的患是安全的,可完全补偿因FB置入所引起的PaO2下降,而对PaCO2影响很小,对于有原发PaCO2升高的患,安全性尚有待进一步研究。  相似文献   
6.
We report the case of a 4-year-old child with an atypical presentation of an aspirated unwitnessed foreign body in the airway. During an attempt to obtain a biopsy of what appeared to be a mucosal growth, the foreign body was removed. This may be the first report of foreign body removal in a child this young, using a flexible fiberoptic bronchoscope. Pediatr Pulmonol. 1994; 18:51–52. © 1994 Wiley-Liss. Inc.  相似文献   
7.
Bile leak after laparoscopic cholecystectomy   总被引:2,自引:2,他引:0  
Summary Laparoscopic cholecystectomy has now become the preferred surgical approach to symptomatic cholelithiasis. With the widespread use of this technique there have appeared reports of complications. We report the case of a patient who developed a cystic duct stump bile leak after laparoscopic cholecystectomy. Percutaneous drainage of the biloma, endoscopic retrograde cholangiopancreatography and papillotomy led to resolution of the problem. The literature on cystic duct stump leaks after laparoscopic cholecystectomy is reviewed and the various therapeutic modalities are outlined.  相似文献   
8.
Eigenstructure assignment using output feedback is reformulated using an auxiliary principle of minimization of control effort. In the general eigenstructure assignment procedure, the feedback gain matrix is uniquely determined for a set of explicitly specified desired eigenvalues and eigenvectors. However, for the controller design proposed in this paper, only the most necessary constraints are imposed on the desired eigenvalues and eigenvectors, and the unspecified model parameters of the closed-loop system are determined by minimizing the control effort. Numerical examples are presented for comparison of the proposed method with standard eigenstructure assignment methods, and an experimental example gives an insight into the feasibility of the proposed control algorithm with application to the vibration control of flexible structures undergoing forced vibration.  相似文献   
9.
Total colonoscopy is arguably the best method available for examination of the colon and rectum. Colonoscopy costs are high and rising and it may be that in the future practitioners will be unable to afford to colonoscope all of the patients presently being examined. This retrospective study was undertaken in an attempt to examine the cost, in terms of lesions missed, of a limited endoscopy programme. During a 15 year period, 1426 colonoscopies were performed at Wellington Hospital, New Zealand. Total colonoscopy was possible in 79% of all patients. Three perforations occurred. Nine patients bled and two required blood transfusion after biopsy or ‘snaring’ of polyps. After exclusion of patients with continuous inflammatory bowel disease (IBD) 75% of all lesions were found in or distal to the descending colon. More cancers were found in patients colonoscoped because of bleeding. Thirty-two of 93 cancers diagnosed were proximal to the descending colon but 18 presented with bleeding. A further seven had a radiological abnormality. Only 7.5% of colorectal cancers would be missed by flexible sigmoidoscopy (65 cm) and 758 of the costs of total colonoscopy would be avoided if only patients presenting with bleeding and IBD were offered total colonoscopy and patients with radiological abnormalities were treated according to the abnormality. This compromise, based on the data presented, may represent a rational way to reduce colonoscopy costs.  相似文献   
10.
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