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61.
目的 制备环丙沙星固体脂质纳米粒并检测其抑菌效果。方法 以胆固醇为脂质,以吐温80为表面活性剂,采用乳化-低温固化法制备固体脂质纳米粒并对其进行表征,包括粒径、Zeta电位、载药量、包封率、分散性以及体外缓释。使用二倍稀释法测定药物对大肠杆菌的最低抑菌浓度。结果 透射电镜扫描可见环丙沙星-固体脂质纳米粒粒径呈球形,直径40~70nm;Zeta电位(-21.8±1.3) mV;包封率为77.54%;载药量31.10%;紫外-可见光谱见纳米粒中环丙沙星280nm处特征性吸收波峰;体外缓释72h的累计释放度为78.6%。环丙沙星固体脂质纳米粒的最低抑菌浓度为0.8μg/mL,环丙沙星最低抑菌浓度为1.6μg/mL。结论 采用乳化-低温固化法成功制备环丙沙星固体脂质纳米粒,方法简便。固体脂质纳米可提高环丙沙星抑菌效果。  相似文献   
62.
目的:评价应用小切口技术进行人工髓核假体置换治疗退行性腰椎间盘疾患的临床初步疗效。方法:2003年6月~2004年9月共施行人工髓核(PDN)置换术12例,男4例,女8例,平均年龄28.5岁。其中腰椎间盘突出症10例,椎间盘源性腰痛2例。包容型腰椎间盘突出症和椎间盘源性腰痛采用前路PDN置换,脱出游离型椎间盘突出症采用后路椎间盘摘除、前路PDN置换;术后评价内容包括临床和影像学结果。结果:平均前路切口长度4.2cm,前路平均手术时间80min,平均术中出血量110ml。PDN置入部位均为L4/5,共置入PR925型假体12枚。所有患者术后腰痛症状得到改善。术后平均随访6.5个月,影像学检查未见假体移位和脱出。结论:应用前路腹膜后小切口进行PDN置换在减少手术创伤的同时,可以有效防止髓核脱入椎管。近期效果肯定,但长期疗效有待进一步观察。  相似文献   
63.
Osteoclastogenesis inhibitory factor (OCIF) is a novel secreted protein that inhibits osteoclastogenesis both in vitro and in vivo. In this study, we examined the effects of OCIF on serum calcium (Ca) concentrations in normal mice and in hypercalcemic nude mice carrying tumors associated with humoral hypercalcemia of malignancy. In normal mice, a single intraperitoneal injection of OCIF reduced serum Ca levels in a dose-dependent manner. Significant decrease in serum Ca (by 1.6 ± 0.3 mg/dL, n = 5) was observed 2 h after the injection of OCIF at 20 mg/kg and the hypocalcemic effect continued for up to 12 h. Serum phosphate (Pi) concentrations also decreased in response to OCIF. Urinary excretion of Ca, Pi, and creatinine did not change significantly after injection of OCIF or vehicle. In hypercalcemic, tumor-bearing nude mice, a single intraperitoneal injection of OCIF at 20 mg/kg resulted in a dramatic decrease in serum Ca (maximal decrease 2.8 ± 0.37 mg/dL, n = 11), which continued for up to 24 h. The results suggest that OCIF decreased serum Ca through its inhibitory effect on bone resorption. Furthermore, it is suggested that OCIF has therapeutic potential for the treatment of hypercalcemic conditions such as malignancy-associated hypercalcemia.  相似文献   
64.
目的 探讨巨噬细胞游走抑制因子(macrophage migration inhibitory factor,MIF)和细胞周期蛋白D1(cyclin D1)在原发性肝细胞癌(hepatocellular carcinoma,HCC)组织中的表达及两者在肝癌发病机制及细胞周期调控中的关系.方法 应用定量PCR及Westem blot技术检测MIF和Cyclin D1在肝癌组织和癌旁组织的表达.化学合成MIF siRNA,将PLC细胞和HepG2细胞分成对照组、MIF siRNA 50 nmol/L干预组、MIF siRNA 1130 nmol/L干预组,脂质体法转染肝癌细胞PLC和HepG2,定量PCR技术和Western blot检测MIF siRNA干扰后MIF和Cyclin D1 mRNA和蛋白的表达变化.结果 MIF和Cyclin D1蛋白在肝癌组织中的相对表达量为0.825±0.13和0.843±0.104;MIF和Cyclin D1 mRNA在肝癌组织中的相对表达量为癌旁组织的(7.31±1.85)倍和(4.27±1.05)倍,与癌旁组织相比,差异均具有统计学意义(FMIF=15.5,P<0.01;fCyclin D1=87.5,P<0.01).应用小RNA干扰技术转染PLC和HepG2肝癌细胞后MIF mRNA分别下调71.2%±7.2%、87.4%±2.9%、74.3%±8.9%、88.4%±4.6%(FPLC=315.5,P<0.01;FHHepG2=201.2,P<0.01);MIF蛋白分别下调为0.33±0.03、0.11±0.02、0.81±0.08、0.36±0.02,并呈剂量依赖关系(FPLC=43.9,P<0.01;FHepG2:133.4,P<0.01).伴随MIF mRNA和蛋白的表达F调Cyclin D1 mRNA分别下调68.2%±3%、78.1%±1.4%、65.8%±4.7%、77.3%±2.6%(FPLC=1569,P<0.01;FHepG2=480.4,P<0.01);Cyclin D1蛋白下调0.28±0.06、0.15±0.03、0.44±0.04、0.13±0.02,亦呈剂量依赖关系,与对照组相比差异有统计学意义(P<0.01),两干预组相比差异有统计学意义(FPLC=35.5,P<0.01;FHepG2=114.7,P<0.01).结论 MIF和Cyclin D1在肝细胞癌中过表达,MIF可能在转录水平调控Cyclin D1的表达,并促使肿瘤细胞通过细胞周期检测点,继续增值和分化,导致肿瘤的形成.  相似文献   
65.
目的初步探讨巨噬细胞移动抑制因子(MIF)在大鼠急性坏死性胰腺炎(ANP)发病中的作用。方法健康雄性SD大鼠60只,随机分成三组,分别为对照组(腹腔注射生理盐水)、ANP组(腹腔注射左旋精氨酸)和干预组(腹腔注射左旋精氨酸+单克隆抗MIF抗体),每组20只。采用左旋精氨酸改良方法建立ANP模型,分别于3、6、12、24h四个不同时点处死5只大鼠,剖腹后从肠系膜上静脉取血,ELISA法测定血清MIF、TNF-α、IL-1、IL-6和IL-8水平 碘比法测定血淀粉酶 切取胰腺组织依据Kusske标准行胰腺病理学评分 Western blot法测定胰腺组织NF-κBp65蛋白的表达。结果ANP组血淀粉酶及胰腺组织病理学评分各时点㈦对照组相比均显著升高,干预组㈦ANP组相比均显著降低(P〈0.01) 胰腺组织NF-κBp65蛋白的表达于造模后3h开始呈持续性上调,与对照组相比其表达显著增多,在干预组其表达水平㈦ANP组相比明显下调(P〈0.01) 血清MIF、TNF-α、IL-1、IL-6各时点在ANP组与正常对照组相比其水平均有明显升高,在干预组其水平㈦ANP组相比显著降低(P〈0.05) 血清IL-8在6、12、24h不同时点水平变化同上述因子,但在3h时点其水平无明显升高 MIF、胰腺组织病理学评分及胰腺组织NF-κBp65蛋白的表达,两两之间均成正相关(P〈0.05)。结论腹腔注射左旋精氨酸建立ANP的模型是稳定的 MIF可能通过调控核因子NF-κB的途径影响血清TNF-α、IL-1、IL-6及IL-8水平而在大鼠急性胰腺炎发病过程中起一定的作用。  相似文献   
66.

Introduction:

Laparoscopy is a constantly evolving field of surgery. New technology, applications, and benefits prompt continual improvement. We have developed a Single Port Access (SPA) surgical technique that allows for the entire cholecystectomy to be performed through a single incision within the umbilicus while maintaining safe standard dissection and retraction techniques of currently performed multi-port laparoscopic cholecystectomy.

Methods:

Fifteen consecutive patients underwent SPA cholecystectomy. Indications were cholelithiasis, cholecystitis, CBD stones, and biliary akinesia. The entire procedure was performed through a single umbilical incision measuring <1.8 cm within the umbilicus. Three trocars and a rigid grasper were inserted through separate fascial sites within the same skin incision. The cholecystectomy procedures are then performed in the standard fashion described in multi-port cholecystectomy.

Results:

Fifteen patients successfully underwent Single Port Access cholecystectomy. One patient required a second 5-mm port site secondary to difficulty with retraction of a large liver. Operative times averaged 107 minutes. Blood loss, patient recovery, and outcomes have been comparable to those of standard multi-port procedures. No umbilical hernias have been seen at 2 years of follow-up.

Conclusion:

We present the SPA cholecystectomy as an alternative to multi-port cholecystectomy. In the first 2 years, SPA surgery has evolved into a technique easily taught and performed without the restrictions of new equipment or added cost.  相似文献   
67.

Objective

To evaluate and compare the diagnostic performances of high-resolution ultrasonography and 99mTc-sestamibi scintigraphy for the preoperative localization of abnormal parathyroid glands and to evaluate the ability of US for additional diagnostic roles in detecting thyroid malignancy in patients with pHPT.

Materials and methods

Preoperative localization images of 115 parathyroid adenomas from high-resolution ultrasonography (US) and 99mTc-sestamibi scintigraphy (SS) were studied from 105 patients, who had undergone parathyroidectomy. Sensitivity, accuracy, and positive predictive value were calculated for the identification of adenomas in lesions and patients for both US and SS, respectively, and US and SS diagnostic performances were compared using generalized estimating equation.

Results

Preoperative imaging by both modalities localized 105 (93.8%) of the 112 parathyroid lesions confirmed at surgery and histology. Sensitivity, accuracy, and positive predictive value were 93.1% and 92.2%, 90.4% and 89.5%, and 96.9% and 96.9% by US and SS, respectively, without any statistically significant differences (P = 0.796, 0.796, 0.879). US found incidental thyroid nodules in 47 patients (47/107, 43.9%), and 7 patients (7/107, 6.5%) were confirmed to have malignancy based on pathology results (all had papillary thyroid carcinoma).

Conclusion

Neck ultrasonography and 99mTc-sestamibi scintigraphy are complementary methods of the preoperative localization of parathyroid adenomas. Neck ultrasounds add an additional thyroid gland evaluation, and can be useful in the detection of incidental thyroid gland lesions, especially malignant nodules.  相似文献   
68.
轻微型肝性脑病作为肝性脑病的早期阶段,临床症状不明显,表现缺乏特异性,目前诊断困难。近年来血氧水平依赖功能磁共振成像(BOLD-fMRI)新技术逐渐运用于肝性脑病的研究,通过探测不同状态下各脑功能区神经元的活动,不仅可以定位异常活动脑功能区,还可以发现脑功能区连接作用改变。尤其是BOLD-fMRI联合其他MR技术的应用,对于轻微型肝性脑病的病理基础和发病机制的研究,实现了从微观到宏观、从结构到功能的全面探讨,能对其早期诊断治疗提供更有价值的依据。  相似文献   
69.
The objective of this retrospective study was to evaluate the outcome of patients with acute necrotizing pancreatitis treated by active percutaneous necrosectomy. By searching the radiological, surgical and internal medicine databases, all patients with acute necrotizing pancreatitis treated by active percutaneous necrosectomy between 1992 and 2004 were identified. Demographic, laboratory, and clinical data, and details about invasive procedures were collected by reviewing patient charts, radiological and surgical reports. The computed tomography severity index (CTSI) scores were determined by reviewing CT images. Eighteen patients were identified. Median Ranson score on admission was 2. The Acute Physiology and Chronic Health Evaluation (APACHE) II score was median 22. Median CTSI score was 7. Initially all patients were treated with CT-guided drainage placement. Because passive drainage proved not to be effective, subsequent minimally invasive, percutaneous necrosectomy was performed. Eight out of 18 patients recovered fully without the need for surgery. Ten of 18 patients required additional surgical necrosectomy. For one of ten patients, percutaneous necrosectomy allowed postponing surgery by 39 days. Four of ten surgically treated patients died: three from septic multiorgan failure, one from pulmonary embolism. Percutaneous minimally invasive necrosectomy can be regarded as a safe and effective complementary treatment modality in patients with necrotizing pancreatitis. It is suitable for a subset of patients to avoid or delay surgery.  相似文献   
70.
目的:探讨不同品种芦荟的蒽甙的抑菌作用研究.方法:选取新鲜的皂质芦荟、木立芦荟、龙山芦荟、中华芦荟和库拉索芦荟叶各10条作为研究对象.测定并比较不同品种芦荟叶皮和叶肉中蒽醌的含量的差异;测定不同品种芦荟叶皮中的蒽醌对大肠杆菌、金色葡萄球菌、枯草芽孢杆菌、铜绿假单胞菌的抑菌效果的差异;测定芦荟蒽醌对各受试菌的最小抑菌浓度.结果:不同品种的芦荟叶皮中的蒽醌含量均高于叶肉中的含量,且差异均具有统计学意义;皂质芦荟、木立芦荟、龙山芦荟叶皮中的蒽醌含量高于中华芦荟和库拉索芦荟,且差异具有统计学意义;不同芦荟品种中的蒽醌对大肠杆菌、金色葡萄球菌、枯草芽孢杆菌、铜绿假单胞菌都有一定的抑菌效果,其中皂质芦荟中的蒽醌对大肠杆菌、金色葡萄球菌、枯草芽孢杆菌的抑菌效果均比较理想,抑菌环直径均超过了7mm;中华芦荟和库拉索芦荟中的蒽醌对各受试菌的抑菌效果相对较差,抑菌环直径均未超过5mm.芦荟中蒽醌溶液在较低浓度下对个受试菌均有不同程度的抑菌能力,其中对大肠杆菌和金色葡萄球菌的最小抑菌浓度均为0.125mg/mL,对枯草芽孢杆菌的最小抑菌浓度为0.063mg/mL,对铜绿假单胞菌的最小抑菌浓度为0.25mg/mL.结论:不同品种的芦荟叶皮中的蒽醌含量均高于叶肉中的含量,皂质芦荟中的蒽醌对各受试菌的抑菌效果比较理想,芦荟蒽醌对枯草芽孢杆菌的抑菌效果最敏感.  相似文献   
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