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101.
胶原酶诱导不同部位脑出血大鼠模型的神经功能比较   总被引:1,自引:1,他引:0  
目的 观察胶原酶诱导纹状体和内囊部位脑出血模型的行为学和神经纤维损伤差异.方法 利用立体定向技术,将一定量的Ⅳ型胶原酶用微量进样器分别精确注入大鼠纹状体和内囊诱导脑出血模型,观察两组大鼠的运动功能差异,并进行大体形态学和神经纤维受损程度的比较.结果 内囊组大鼠的运动功能受损程度明显重于纹状体组大鼠,前者的神经纤维破坏程度显著重于后者.结论 不同部位的脑出血模型的神经损害程度存在差异,内囊区脑出血模型更适合于研究神经纤维的损伤机制及神经纤维的再生和修复.  相似文献   
102.
针对目前我国户外广告发展状况,简述了计算机技术在户外广告设计、规划中的应用及其影响。  相似文献   
103.
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   
104.
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   
105.
This is a retrospective review of the results at our institution of using multi-detector CT angiography (CTA) to localise lower gastrointestinal (GI) bleeding. We hypothesised that in our patient population: (i) CTA was unlikely to demonstrate bleeding in patients who were haemodynamically stable; (ii) in haemodynamically unstable patients in whom CTA was undertaken, the results could be used to select patients who would benefit from catheter angiography; and (iii) in haemodynamically unstable patients in whom CTA was undertaken, a subgroup of patients could be identified who would benefit from primary surgical treatment, avoiding invasive angiography completely. A retrospective review was conducted of the clinical records of all patients undergoing CTA for lower GI haemorrhage at our institution between 1 January 2005 and 30 June 2007. Out of the 20 patients examined, 10 had positive CTAs demonstrating the bleeding site. Nine were haemodynamically unstable at the time of the study. Four patients with positive CT angiograms were able to be treated directly with surgery and avoided invasive angiography. Ten patients had negative CTAs. Four of these were haemodynamically unstable, six haemodynamically stable. Only one required intervention to secure haemostasis, the rest stopped spontaneously. No haemodynamically stable patient who had a negative CTA required intervention. CTA is a useful non-invasive technique for localising the site of lower GI bleeding. In our patient population, in the absence of haemodynamic instability, the diagnostic yield of CTA was low and bleeding was likely to stop spontaneously. In haemodynamically unstable patients, a positive CTA allowed patients to be triaged to surgery or angiography, whereas there was a strong association between a negative CTA and spontaneous cessation of bleeding.  相似文献   
106.
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   
107.
Objective The aim of this study was to understand the role of PET/CT in monitoring the therapeutic effect of radiotherapy (RT) on lung cancer with Wistar rats. Methods Thirty Wistar in-bred strain rats (6-8 weeks, weighed 180-280 g, female, ordinary) were made into Lewis pulmonary tumor model rats. 18F-fluorodeoxyglucose (FDG) PET/CT was performed when tumor reached 1.5-2.0 cm in greatest diameter (4-6 weeks) as a baseline. In order to get the optimal time point of PET/CT for moni-toring RT effect in rat cancer model, PET/CT was performed at the 3rd day, 1st, 2nd, 3rd, and 4th week after giving single dose of 5 Gy to each rat. Standardized uptake values (SUV) from FDG PET were measured and rats were sacrificed at different time point for validation. Besides, the expressions of glucose transport1 (Glut1) in tumor tissue were studied using immunohistochemistry. The level of tumor cell apoptosis, degra-dation, and necrosis were observed. SPSS 11.0 software was used for data analyses. Results A negative correlation of SUV uptake and time after RT and negative correlation of Glut1 expression and time after RT were observed in rat tumors, respectively. Positive correlation of SUV uptake and Glut1 expression in rat tumors was observed (Spearman rank correlation test, rs = 0.97, P < 0.01). Before RT, the SUV in rat tumor was 1.28 ± 0.31 and was decrease to 1. 00 ± 0.23 at the 3rd day and 0.18 ± 0. 10 at the 4th week after RT (F=15. 126, P<0.05). Before RT, the Glut1 in rat tumor was 0.2558 ±0.03 and was decrease to 0. 2320 ± 0. 01 at the 3rd day and 0. 1320±0.04 at the 4th week after RT. The amounts of tumor cell apopto-sis, degradation, and necrosis increased with time after RT. Conclusion Though FDG PET could monitor the therapeutic effect at the 3rd day after giving single dose of RT to rat lung tumor model, the optimal time was the the 4th week after treatment.  相似文献   
108.
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   
109.
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   
110.
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   
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