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81.
Gastroplasty is currently one of the most common surgical procedures performed on the morbidly obese for weight loss. An adequate
result can be assured only if the pouch that is created is less than 30 ml and the channel that connects that pouch to the
distal stomach is approximately 1 cm in diameter. The current method to size the pouch is to occlude the esophagus and the
outlet of the pouch and to measure with a manometer through a naso-gastric tube. We contend this method is both time consuming
and adds to the potential of complications. Through the use of a calibration balloon tube the size of the pouch can be quickly
and safely estimated. It can also be used to size the channel between the pouch and the distal stomach and check for leaks.
The technique of how this tube has been used over the past 6 years is described. By the use of a calibration balloon tube,
three problem areas in gastric stapling surgery for morbid obesity are avoided, namely: inappropriate pouch size, inappropriate
channel size and postoperative leaks. 相似文献
82.
Nebulization of aqueous solutions is a convenient delivery system to deliver drugs to the lungs because it can produce droplets small enough to reach the alveolar region. However, the droplet size might be affected by the changes in the temperature and the concentration of the nebulizing solution in the reservoir during nebulization. In this study, the changes in the droplet size over the nebulization time using a PariBoy air-jet and a Multisonic ultrasonic nebulizer have been studied. The findings were related to changes in the temperature, concentration, surface tension, viscosity and saturated vapour pressure of the nebulizing solution. By using the jet nebulizer, an increase in the droplet size followed by a decrease has been observed. This observation could be attributed to the approx. 7 degrees C reduction of the temperature during the first 2 min in the jet nebulizer reservoir which increased the viscosity of the nebulizing solution. After this initial period of time, the increasing drug concentration induced a reduction of the surface tension and, consequently, a decrease in the droplet size. However, with the ultrasonic nebulizer a temperature increase of approx. 20 degrees C during the first 6 min in the nebulizing solution was observed leading to a decrease in droplet size, viscosity and surface tension and an increasing saturated vapour pressure. This again led to smaller average droplet sizes. 相似文献
83.
Drug release from reservoir pellets compacted with some excipients of different physical properties 总被引:2,自引:0,他引:2
sa Tunn Elisabet Brjesson Gran Frenning Gran Alderborn 《European journal of pharmaceutical sciences》2003,20(4-5):469-479
The aim of the present study was to investigate the influence of the size and the porosity of excipient microcrystalline cellulose (MCC) particles on the densification and the deformation during compaction and the consequent effect on the drug release from reservoir pellets. Drug pellets consisting of salicylic acid and microcrystalline cellulose were prepared by extrusion-spheronisation and spray-coated with ethyl cellulose (ethanol solution). Excipient pellets of different size and porosity were prepared by extrusion-spheronisation or direct spheronisation. Five binary mixtures of reservoir pellets and excipient particles were prepared in the proportion 1:7 and lubricated. After compaction the reservoir pellets were retrieved and analysed to determine the intragranular porosity, surface area, shape and drug release. The reservoir pellets were shown to undergo extensive deformation and densification during compaction, resulting in a preserved or even prolonged drug release time. The mode of deformation of the reservoir pellets seems to be critical for the compression-induced change in drug release. Formation of large indents has a negative effect on the release time, while the use of small particles or small deformable agglomerates has a protective effect. We also hypothesize that the coating structure changes during compaction and the final structure of the coating is the net effect of two parallel processes, one reducing and one prolonging the drug transport time across the coating. 相似文献
84.
非小细胞肺癌淋巴结大小与转移的关系 总被引:4,自引:0,他引:4
目的:评估非小细胞肺癌淋巴结大小与转移的相关性.方法:从形态测量学角度,分析258例非小细胞肺癌患者纵隔和肺门的淋巴结.记录每例淋巴结数目、最大径及病理结果.计算转移频数与淋巴结大小的相关性.回顾性分析其中80例患者术前CT扫描的淋巴结所见,与组织病理学诊断相对照.结果:检查258例标本的2 892枚淋巴结.140例患者为pN0期,118例为淋巴结阳性.2 487枚淋巴结(86.0%)无转移,405枚淋巴结(14.0%)有转移.无转移淋巴结平均直径是(7.05±3.7)mm,转移淋巴结是(10.7±4.7)mm,(P<0.005).1 954枚无转移淋巴结(78.5%)和180枚转移淋巴结(44.3%)直径<10mm.140例无转移淋巴结的患者中,102例(72.9%)至少有一枚淋巴结>10mm118例转移患者中,13.0%淋巴结<10mm.80例CT扫描评估的敏感性是57.0%,特异性80.2%结论:淋巴结大小不能作为评估非小细胞肺癌转移浸润的可靠参数. 相似文献
85.
宫颈肿瘤大小在Ⅰb ~Ⅱ期宫颈癌中的临床意义 总被引:2,自引:0,他引:2
[目的]探讨宫颈肿瘤大小的临床意义。[方法]自1992年1月至1997年12月收治手术治疗的Ⅰb~Ⅱ期(FIGO分期)宫颈癌患者398例,将其中302例有完整资料的患者根据宫颈肿瘤的最大横径分为<4cm组和≥4cm两组,分析了两组患者的生理病理因素、失败模式及其预后,并采用COX模型进行多因素生存分析。[结果]与<4cm组比较,≥4cm组中分期较晚,淋巴结转移,高位淋巴结转移及宫颈深肌层浸润的比例更高。宫颈大肿瘤组(≥4cm组)的单纯盆腔复发率(22.0%)高于<4cm组(7.6%)。宫颈大肿瘤组(≥4cm组)的5年生存率(59.29%)明显低于<4cm组(82.15%,P<0.01)。多因素生存分析显示宫颈局部肿瘤大小,淋巴结转移,阴道残端,肌层浸润深度及组织学类型是影响预后最重要的因素(P<0.05)。[结论]宫颈肿瘤≥4cm的患者更易发生深肌层浸润和盆腔淋巴结转移,盆腔复发率高,预后差。 相似文献
86.
两性霉素B脂质体粒度测定方法研究 总被引:1,自引:0,他引:1
目的:建立两性霉素B脂质体粒度检测方法,通过测定一组性质不同的样品,找出最佳测定方法。方法:用计算机的图像一数字处理技术结合扫描电镜、透射电镜和激光光散射粒度测定仪分别测定两性霉素B脂质体的粒度。结果:电镜法测定两性霉素B脂质体的粒度为20—100nln,平均粒径为55—75nm;激光光散射法测定两性霉素B脂质体的粒度为30—200nm,平均粒径为50—180nm。结论:激光光散射法能较好反映两性霉素B脂质体在使用时的真实粒度,且方法快速、简便,是一种较好的两性霉素B脂质体粒度测定方法。 相似文献
87.
Helicobacter pylori Risk Associated with Sibship Size and Family History of Gastric Diseases in Japanese Adults 总被引:1,自引:4,他引:1
Helicobacter pylori is thought to be a cause of gastric cancer. Risk factors of H. pylori positivity were investigated among 4,361 public service workers in Japan. Sera and information on family history and lifestyle were collected, and H. pylori antibody was measured using the sera. Sex- and age-adjusted odds ratios of factors expected to influence H. pylori seropositivity were calculated. The factors with a significant influence were included in a logistic regression model and the final model was obtained by backward elimination. Sibship size (4 and more vs. 1), smoking habit (current vs. never), and paternal and siblings' histories of gastric diseases showed significant relationships to H. pylori seropositivity, with odds ratios (95% confidence intervals) of 1.5 (1.0–2.1), 0.8 (0.7–0.9), 1.5 (1.3–1.8) and 1.7 (1.1–2.6) respectively. However, spouse's history was not related. In the final model, sibship size and paternal history remained as positive factors, and smoking as a negative one. Contradictory results on the relationship between H. pylori status and smoking among recent studies indicate the existence of hidden confounding factors. It is suggested that infection from family members in childhood considerably affects the H. pylori status of Japanese adults, whereas infection between adults is rare. 相似文献
88.
We have applied stereological methods to estimate the number and perikaryal size of primary sensory neurons in celloidin-embedded trigeminal ganglia of male albino rats, specifically looking for inter-individual and side variability. The mean total number of neurons per ganglion was 35,300, with a moderate variability among ganglia. On average, 66% of the neurons were classified as A-type and 34% as B-type. Although for individual cases there could be notable side differences in the number of neurons of each type, on a population basis these differences were not significant. Mean neuronal volume was four times larger for A- than for B-cells, and both populations exhibited a moderate variability among individuals. High intra-animal side differences were found for A-cells, which were on average a significant 23.5% larger in the right ganglia. B-cells did not show significant side differences. The distribution of individual volumes around the mean value was consistently skewed to the right, particularly in the case of A-cells, which partially overlapped with the largest B-cells. In the right ganglion the distribution of A-cells, but not of B-cells, showed a rightward bias, revealing the increase in bigger neurons. The existence of larger A-type neurons in the right trigeminal ganglion may provide a structural substrate for some somesthetically based complex behaviors which are best performed by rats using their right vibrissae. 相似文献
89.
目的 分析不同口径连续环形撕囊对后囊浑浊的影响。方法 回顾 10 1眼分别以囊口直径 4 5~ 5 0mm和 6 0~7 0mm连续环形撕囊 ,行白内障超声乳化联合后房人工晶状体植入术 ,观察术后后囊浑浊的情况。结果 随访 1年 ,A组采用小口径连续环形撕囊 68眼中 1年发生后囊浑浊 2 5眼 ( 3 6 8% ) ,其中 2级 2 1眼 ( 3 0 9% ) ,3级 4眼 ( 5 9% ) ;B组采用大口径连续环形撕囊 3 3眼中 1年发生后囊浑浊 2 6眼 ( 78 8% ) ,其中 2级 18眼 ( 5 4 5 % ) ,3级 8眼 ( 2 4 2 % )。 2组间发生后囊浑浊 2级、3级 ( χ2 =4 2 976,P <0 0 5 ;χ2 =5 5 0 73 ,P <0 0 5 )差异均具有显著意义。结论 小口径截囊者后囊浑浊发生率低于大口径截囊者。 相似文献
90.
紫杉醇注射液的制备及其物理稳定性的初步评价 总被引:3,自引:0,他引:3
目的制备紫杉醇注射液 ,初步评价其物理稳定性。方法采用混合表面活性剂和混合溶剂对紫杉醇进行增溶 ,制备了紫杉醇注射液。选择适当的等渗液稀释后 ,用激光NICOMP3 80 /ZLS系统测不同时间下相应动态光散射光谱的体积分布频率、散射强度分布频率图谱。结果与结论注射液稀释后的动态光散射光谱 6h内无明显差别 ,粒径大小及分布均符合静脉滴注要求。该制剂制备工艺简单 ,室温放置 1 5a后注射液外观澄清 ,稀释后测定粒径与粒径分布无明显变化 ,物理稳定性良好。 相似文献