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91.
A membrane-coated fiber (MCF) array approach was developed for quantitative assessment of skin absorption from chemical mixtures, which was based on the similarity in the absorption mechanisms of the MCF membrane and the stratum corneum of the skin. A set of probe compounds were used to detect the relative molecular interaction strengths of chemicals with the vehicle and the membranes, which provided a linkage between the skin permeability (log k) and MCF partition coefficients (log KF). A predictive model was established via multiple linear regression analysis of the data matrix of experimentally measured log k value and log KFm values; log k=a0+a1 log KF1+a2 log KF2+...+an log KFm, where m is the number of diverse MCFs. Twenty-five probe compounds and three MCFs (polydimethylsiloxane for lipophilic, polyacrylate for polarizable, and CarboWax for polar interactions) were used to demonstrate the model development processes in the MCF array approach. The skin permeability of the probe compounds was measured with conventional diffusion cell experiments using dermatomed porcine skin. Three predictive models were established for skin permeability prediction from chemical mixtures in water, 50% ethanol, and 1% sodium lauryl sulfate (SLS) with R2 values of 93, 91, and 83, respectively. The log k and log KF values were considerably altered by the addition of ethanol or SLS into the dose vehicle; however, their correlations to skin permeability remained strong under various conditions. These results suggested that the experimentally based MCF array approach can be used to predict skin absorption from chemical mixtures in different vehicles or formulations. 相似文献
92.
Ten patients with subhepatic fluid collections complicating laparoscopic Cholecystectomy were successfully treated by interventional radiological procedures. The series included five abscesses, three hematomas, one biloma, and one serous collection. Abdominal pain or fever developed from 3 to 21 days after the laparoscopic intervention. All patients were asymptomatic 72 h after percutaneous drainage and there were no complications related to the procedure. Subhepatic fluid accumulations are common findings after laparoscopic cholecystectomies and have been considered an unreliable indicator of infection or other postoperative complications. However, the significance of these collections should not be underestimated in symptomatic patients. In such cases we propose diagnostic aspiration and drainage, when necessary, to safely and promptly establish the precise diagnosis and treatment. More serious complications can be avoided by early percutaneous intervention. 相似文献
93.
鼻内窥镜诊治脑脊液漏的临床研究 总被引:1,自引:0,他引:1
目的 探讨鼻内窥镜手术治疗脑脊液鼻漏临床相关因素。方法 对17例(19漏)内窥镜下修补脑脊液鼻漏患者的临床资料作回顾性分析。结果 脑脊液鼻漏17例中,外伤性15例,自发性2例,内窥镜下瘘口修补术一次性治愈15例,成功率88.2%,失败2例,再次修补成功,其中1例颅内高压术后腰穿持续引流减压。结论 内窥镜手术修补脑脊液鼻漏准确、微创;冠位CT薄层扫描对术前瘘口解剖定位有重要意义;影响手术效果的因素与修补材料的固定有关,与修补材料本身无明显关系;术后适当腰穿引流对于临床提示颅内压高、修补区薄弱病例仍需采用。 相似文献
94.
目的:评价经皮顺行交锁钉治疗股骨干骨折的临床疗效.方法:对79例82处股骨干骨折采用髋部小切口经皮顺行交锁钉治疗,观察疗效.结果:75例(92%)获得了良好的解剖对位并达到一期愈合,6例(8%)迟缓愈合.另外,由于再次手术1例(1%)发生了深部感染.失血量较少(平均小于100 mL),切口平均长25 mm.1年后随访只有10%髋部疼痛.结论:与传统手术方式相比,经皮技术术中出血少、对周围组织创伤少,是一个安全又有效的方法. 相似文献
95.
Shinya Kodashima Mitsuhiro Fujishiro Naohisa Yahagi Naomi Kakushima Masanori Nakamura Masao Omata 《Digestive endoscopy》2006,18(2):151-153
Endoscopic resection has been accepted as the standard treatment for intramucosal gastric tumors of differentiated type. However, the indication was limited to small tumors to achieve en bloc resection and prevent local recurrence in cases of conventional endoscopic mucosal resection (EMR) such as the strip biopsy and the cap technique. To avoid multi‐fragmental resection, we have developed endoscopic submucosal dissection (ESD) as a new endoscopic resection technique. ESD is a remarkable technique, because we make it possible to remove the lesions en bloc regardless of size, shape, coexisting ulcer, and location. However, it is difficult or impossible to resect recurrent tumors en bloc in conventional EMR owing to hard fibrosis, and some patients need laparotomy. Using ESD, we can dissect the submucosal layer as we directly look at the submucosa, and remove the lesion safely and reliably even in cases of hard fibrosis. The key to treatment of recurrent tumors in ESD are as follows: (i) using enough submucosal injection solution (we use a mixture of Glyceol and 1% 1900 kDa hyaluronic acid preparation); (ii) incising the mucosa without fibrosis; (iii) understanding characteristics of various cutting devices, and changing other devices in difficult situations. In these ways we can remove the majority of the recurrent tumors en bloc. Hence, we consider that ESD is a very effective treatment which achieves excellent en bloc and complete resection rates and enables patients with intramucosal gastric tumors to a recurrent‐free survival even in recurrent tumors. 相似文献
96.
Grant R. Caddy MD MRCP Consultant Gastroenterologist Tony C.K. Tham MD FRCP Consultant Gastroenterologist 《Best Practice & Research: Clinical Gastroenterology》2006,20(6):1085
Symptomatic BDS commonly cause significant morbidity and attempt at stone removal should be attempted if possible. Complications of CBDS include biliary colic, jaundice, cholangitis and pancreatitis. Investigations aimed to predict the presence of stones within the bile duct include serum bilirubin, AST, ALP, common bile duct diameter and age as independent predictors of choledocholithiasis. TUS is a sensitive test in detecting bile duct dilatation but the sensitivity is reduced in its ability to detect choledocholithiasis. A NIH consensus statement found that ERC, MRC and EUS were comparable in their sensitivities, specificities and accuracy rates for detection of choledocholithiasis. ERC and stone removal using a balloon or basket is often performed following EST. EBD may be performed if patients have uncorrected coagulopathies but the risk of pancreatitis is higher than for EST (although the risk of bleeding complications is lower for EBD). ML is often required in difficult to remove CBDS and using this device, CBDS can be removed in 90–95% of cases. Other forms of lithotripsy including laser lithotripsy and EHL are confined to specialised centres and the evidence for their use is based on small studies. ESWL may clear stones from the bile duct in up to 93% of patients but frequently ERC and stone fragment removal is required post ESWL. The role of medical therapy in difficult to remove CBDS (or in CBDS in patients with severe co-morbid illness preventing ERC + stone removal) is still currently uncertain due to a lack of large randomised control trials. 相似文献
97.
Edward McNulty Joshua Cohen Tony Chou Kendrick Shunk 《Catheterization and cardiovascular interventions》2006,67(1):46-48
We present two patients with angulated, proximal left circumflex lesions, one a chronic total occlusion and one an acute subtotal occlusion. In both cases, use of the deflectable tip Venture Catheter (Velocimed, Minneapolis, MN) facilitated guide wire passage and successful percutaneous coronary intervention (PCI) after prior attempts at guide wire passage with standard wires were unsuccessful. 相似文献
98.
Bruce E. Lewis Colin Sumida Ming H. Hwang Henry S. Loeb 《Catheterization and cardiovascular interventions》1992,26(4):295-299
Four selected cases of emergent IABP insertion in PV patients are presented. After angiographic documentation of critical iliac stenosis, conservative peripheral angioplasty was performed prior to IABP insertion. No patient experienced a peripheral ischemic event associated with IABP use. © 1992 Wiley-Liss, Inc. 相似文献
99.
A gastrostomy was fashioned laparoscopically in a 15 year old patient with a severe head injury. A preceding attempt at percutaneous endoscopic gastrostomy had failed. The gastrostomy tube was inserted into the stomach under vision and the stomach attached to the anterior abdominal wall by sutures. 相似文献
100.
目的:回顾性分析27例无精子症患者经皮附睾穿刺取精术(PESA)所获精子冷冻复苏后行卵细胞胞质内单精子注射(ICSI)治疗后的效果及妊娠结局。方法:将诊断性附睾穿刺以及PESA治疗周期ICSI后所剩余活精子以常规方法加以冷冻,将复苏后找到了足量活精子并行ICSI的病例归为冻精组,而采用新鲜PESA活精子ICSI的病例则归为对照组。比较冻精组与对照组的受精率、种植率、临床妊娠率,同时分析两组间的妊娠并发症、新生儿出生及畸形等情况。结果:冻精组15个周期、对照组100个周期分别注射MⅡ期成熟卵子163、1 157个,受精率冻精组显著高于对照组(84.05%vs73.29%,P<0.05),种植率、临床妊娠率则两组间差异无显著性(23.07%vs15.73%;53.33%vs37.00%,P>0.05),新生儿出生体重差异亦无显著性(P>0.05)。冻精组共妊娠8例,已分娩5例,继续妊娠3例。对照组妊娠37例,已分娩30例,1例死胎;继续妊娠3例;流产4例。两组均未出现重大的妊娠并发症及新生儿畸形。结论:采用PESA冷冻精子ICSI是治疗男性无精子症的一种经济、有效、安全的方法;但PESA冻精复苏率有待于进一步提高。 相似文献