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91.
Bacterial ghosts (BGs) are empty bacterial envelopes of Gram-negative bacteria produced by controlled expression of cloned gene E, forming a lysis tunnel structure within the envelope of the living bacteria. BGs are devoid of cytoplasmic content and possess all bacterial bio-adhesive surface properties in their original state while not posing any infectious threat. BGs are ideally suited as an advanced drug delivery system (ADDS) for toxic substances in tumor therapy. The inner space of BGs can be loaded with either single components or combinations of peptides, drugs or DNA which provides an opportunity to design new types of (polyvalent) drug delivery vehicles. Uptake of BGs loaded with Doxorubicin (Dox) by CaCo2 cells led to effective Dox release from endo-lysosomal compartments and accumulation in the nucleus. Viability and proliferative capacity of the cells were significantly decreased (2–3 orders of magnitude) after internalization of Dox loaded BGs as compared to cells incubated with free Dox. The same effect was observed with leukemia cells. Melanoma cells also revealed a high capability to internalize BGs. These results indicate that BGs are able to target a range of types of cancer. BGs have also been investigated as DNA delivery vectors. Studies show DNA loaded BGs are efficiently phagocytosed and internalized by both professional APCs and tumor cells with up to 82% of cells expressing the plasmid-encoded reporter gene. Our studies with BGs as an ADDS system contribute (i) to optimize drug delivery for the treatment of cancer; (ii) define specific conditions for selection and preparation of BG formulations; (iii) and provide a background for the clinical application of BGs in cancer therapy.  相似文献   
92.
PURPOSE The purpose of this study was to examine the psychological effects of physical and verbal abuse in a cohort of older women.METHODS This observational cohort study was conducted at 40 clinical sites nationwide that are part of the Women’s Health Initiative (WHI) Observational Study. We surveyed 93,676 women aged 50 to 79 years using the mental health subscales and the combined mental component summary (MCS) score of the RAND Medical Outcomes Study 36-item instrument.RESULTS At baseline, women reporting exposure to physical abuse only, verbal abuse only, or both physical and verbal abuse had a greater number of depressive symptoms (1.6,1.6, and 3 more symptoms, respectively) and lower MCS scores (4.6, 5.4, and 8.1 lower scores, respectively) than women not reporting abuse. Compared with women who had no exposure to abuse, women had a greater increase in the number of depressive symptoms when they reported a 3-year incident exposure to physical abuse only (0.2; 95% confidence interval [CI], −0.21 to 0.60), verbal abuse only (0.18; 95% CI, 0.11 to 0.24), or both physical and verbal abuse (0.15; 95% CI, −0.05 to 0.36); and they had a decrease in MCS scores when they reported a 3-year incident exposure to physical abuse only (−1.12; 95% CI, −2.45 to 0.12), verbal abuse only (−0.55; 95% CI, −0.75 to −0.34), and both physical and verbal abuse (−0.44; 95% CI, −1.11 to −0.22) even after adjustment for sociodemographic characteristics.CONCLUSION Exposure to abuse in older, functionally independent women is associated with poorer mental health. The persistence of these findings suggests that clinicians need to consider abuse exposure in their older female patients who have depressive symptoms. Clinicians caring for older women should identify women at risk for physical and verbal abuse and intervene appropriately.  相似文献   
93.
介绍了远程医疗会诊车的性能特点、使用方法、功能及应用范围并提出了改进建议。  相似文献   
94.
95.
This cross-sectional analysis evaluated the effect of age and body mass index (BMI) on Three-Factor Eating Questionnaire scores in males. Subjects (n = 60) were recruited according to BMI status. Each completed the 51-item Three-Factor Eating Questionnaire. The group was split at the median age to produce a “younger” and “older” group for statistical analysis. A 2-way between-groups analysis of variance revealed a significant main effect of BMI on disinhibition (P = .003) and hunger (P = .041) with higher levels found in overweight males compared to healthy-weight counterparts. A significant main effect of age on hunger (P = .046) demonstrated older males were less susceptible to hunger than younger males. These insights provide a better understanding of eating behavior across the male life cycle and may assist health professionals to better guide men in weight management in the light of rising overweight/obesity.  相似文献   
96.
目的探讨内源性热休克蛋白90(HSP90)在缺氧心肌细胞丝氨酸苏氨酸蛋白激酶(AKT)相关信号通路中的作用。方法建立新生Wistar大鼠心肌细胞缺氧模型,将细胞分为正常组、缺氧组、加入HSP90特异性阻断剂格尔德霉素后再缺氧组(格尔德霉素+缺氧组)。于缺氧后1、3、6、12、24、48h用噻唑蓝法检测心肌细胞的活力;缺氧24h,原位缺口末端标记法检测心肌细胞凋亡指数(AI);缺氧1、3、6、12、24h,蛋白质印迹法检测大鼠心肌细胞中内源性HSP90及AKT表达水平。结果(1)缺氧24、48h,缺氧组、格尔德霉素+缺氧组细胞活力均较正常组明显下降(P〈0.05);格尔德霉素+缺氧组细胞活力缺氧12h即开始明显下降,缺氧48h时明显低于缺氧组(P〈0.05)。(2)缺氧24h,缺氧组细胞AI为(10.7±1.2)%,明显高于正常组[(1.9±0.3)%.P〈0.05];格尔德霉素+缺氧组细胞AI为(26、3±5.3)%,明显高于缺氧组(P〈0.01)。(3)缺氧12h,缺氧组心肌细胞内源性HSP90及AKT表达水平高于正常组与格尔德霉素+缺氧组;缺氧24h,缺氧组有所下降.格尔德霉素+缺氧组则下降更明显。结论内源性HSP90对维持心肌细胞的活力有重要作用.缺氧心肌细胞AKT表达水平可受内源性HSP90表达水平的影响。  相似文献   
97.
OBJECTIVE: We report on 3 patients who underwent laparoscopic antireflux procedures for persistent symptoms of GERD after biopolymer injection. METHODS: Experienced laparoscopic surgeons completed all 3 procedures laparoscopically. In 2 patients, there was an extramural extravasation of the polymer outside and adherent to the esophageal wall. In these patients, a partial posterior fundoplication was used. The third patient, who had the polymer material deposits removed preoperatively by endoscopic mucosal resection, underwent a Nissen fundoplication. RESULTS: Postoperative recovery was uneventful in all cases. At follow-up of 6 to 12 months, all patients were symptom free, off medical therapy, and experiencing no dysphagia. CONCLUSION: Surgical therapy for patients after failed biopolymer injection is safe and effective. The choice of surgery may depend on whether the polymer mass can be removed preoperatively.  相似文献   
98.
目的 构建含人端粒酶反转录酶(hTERT)核心启动子调控的人钠/碘同向转运体(hNIS)基因重组腺病毒,并靶向转染至肺癌A549细胞中特异性表达.探讨hTERT启动子调控的hNIS基因介导放射性碘治疗肿瘤的可能性.方法 应用AdEasy系统构建重组腺病毒Ad-hTERT-hNIS,同时构建巨细胞病毒(CMV)启动子调控的hNIS重组腺病毒Ad-CMV.hNIS作为阳性对照,不含hNIS的重组腺病毒Ad-CMV作为阴性对照.应用反转录.聚合酶链反应(RT-PCR)方法验证hTERT在转染肿瘤细胞中的转录活性,摄碘实验检测表达的hNIS蛋白功能,细胞克隆形成实验评价131I对转染肿瘤细胞的毒性作用.结果 成功构建重组腺病毒Ad-hTERT-hNIS、Ad-CMV-hNIS及Ad-CMV,并经PCR验证正确.RT-PCR证实hNIS cDNA能从Ad-hTERT-hNIS转染的细胞中扩增出来.Ad-hTERT-hNIS和Ad-CMV-hNIS转染的肺癌A549细胞摄碘能力比阴性对照组Ad-CMV转染的细胞分别提高了23和31倍,且摄碘能力可以被NaClO4抑制.Ad-hTERT-hNIS和Ad-CMV-hNIS转染的肺癌A549细胞均可被131I杀死,2组细胞成活率分别为(31.2±1.45)%和(23.6±4.08)%,而阴性对照组和未转染病毒组分别为(89.0 ±2.99)%和(91.2 ±4.63)%.结论 hTERT启动子调控的hNIS重组腺病毒转染肿瘤细胞后,应用131I治疗有望成为一种新的基因靶向治疗手段.  相似文献   
99.
BACKGROUND/PURPOSE: Laser-induced autofluorescence spectroscopy provides excellent possibilities for medical diagnostics of different tissue pathologies including cancer. However, to create the whole picture of pathological changes, investigators collect spectral information from patients in vivo or they study different tumor models to obtain objective information for fluorescent properties of every kind of healthy and diseased tissue. Therefore, it is very important to find the most appropriate, and close to the human skin, animal samples from the fluorescence point of view, which will allow the extrapolation of the animal data to human spectroscopic diagnostics. METHODS: In the present work, we examined the autofluorescence properties of different animal skin tissues, which are considered as the most common skin models. A nitrogen laser was used as an excitation source. Samples of healthy mouse, chicken and pig skin in vivo and/or ex vivo were studied and were compared with results obtained from investigations of healthy human skin in vivo. RESULTS AND CONCLUSION: Specific features of the recorded spectra are discussed and the possible origin of the obtained fluorescence signals is proposed. Quantitative evaluation of data extrapolation for each skin type is also depicted.  相似文献   
100.
金军  付伟  钟声 《中国骨伤》2007,20(12):821-822
目的分别应用三针锁针加压器外固定和空心拉力钉内固定疗法治疗股骨颈骨折,探讨股骨颈骨折最佳治疗方法.方法应用三针锁针加压器外固定治疗股骨颈骨折63例,其中男24例,女39例;年龄55~89岁,平均(64.5±3.2)岁;Garderl Ⅰ型2例,Ⅱ型15例,Ⅲ型38例,Ⅳ型8例.应用空心拉力钉内固定治疗63例,其中男29例,女34例;年龄45~76岁,平均(62.2±2.9)岁;Garden Ⅰ型4例,Ⅱ型24例,Ⅲ型28例,Ⅳ型7例.对其疗效进行分析.结果126例除2例死亡外均得到随访.115例愈合,其中10例股骨头坏死.外固定组愈合58例,股骨头坏死4例,死亡1例;内固定组愈合57例,股骨头坏死6例,死亡1例.根据Harris功能评定标准评价疗效,外固定组62例中优24例,良26例,可8例,差4例,优良率80.65%;内固定组62例中优23例,良27例,可6例,差6例,优良率80.65%.Harris评分外固定组平均(80.40±1.21)分,内固定组平均(79.14±1.47)分,两组Harris评分比较差异无统计学意义(P>0.05).结论采用内外固定治疗股骨颈骨折疗效无明显差异,但外固定创伤小、费用低、可早期离床;而采用拉力钉内固定器医疗成本高,卧病时间相对较长,且需二次手术取内固定钉.  相似文献   
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