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891.
Effect of age on calcium-dependent proteins in hippocampus of senescence-accelerated mice 总被引:5,自引:0,他引:5
H. J. Armbrecht M. A. Boltz V. B. Kumar J. F. Flood J. E. Morley 《Brain research》1999,842(2):189-293
The senescence-accelerated P8 mouse (SAMP8) is a well-characterized model for the age-related decline in acquisition and retention. Calcium-dependent protein kinase C (PKC) and calcium-calmodulin-dependent protein kinase (CAM K) have been implicated in these processes in the hippocampus. Therefore, the expression of hippocampal PKC and CAM K was determined in SAMP8 mice aged 4, 8, and 12 months. As measured by Western blotting, total hippocampal PKC-gamma protein declined linearly with age. In addition, the distribution of the PKC-gamma also changed with age. The amount of PKC in the particulate fraction declined linearly with age relative to the soluble PKC. The decline in total PKC and particulate PKC correlated with the previously reported decline in retention but not with the decline in acquisition. Western blotting revealed no consistent change in CAM KII protein levels. In addition to protein levels, Ca-dependent protein kinase activity may also be affected by changes in intracellular Ca concentration. Therefore, the levels of calbindin and the plasma membrane Ca pump, two proteins involved in maintaining low levels of intracellular Ca, were measured in the hippocampus. Calbindin protein declined progressively with age, but there was no significant change in total plasma membrane Ca pump expression. These studies demonstrate a decrease in the amount and distribution of hippocampal PKC-gamma in the SAMP8 between 4 and 12 months that is associated with decreased retention. 相似文献
892.
目的探讨不同治疗方案树幽门螺杆菌(HP)感染患者的治疗效果。方法选择HP感染患者313例,其中消化性溃疡218例,随机分成治疗组[质子泵抑制剂(PPI)+克拉霉素+阿莫西林106例,其中消化性溃疡75例];对照Ⅰ组(PPI+克拉霉素+硝基咪唑类103例,其中消化性溃疡73例);对照Ⅱ组(PPI+阿莫西林+硝基咪唑类104例;其中消化性溃疡70例)。结果PPI+克拉霉素+阿莫西林的HP根除率显著高于PPI+克拉霉素+硝基咪唑类组及PPI+阿莫西林+硝基咪唑类组;同时PPI+克拉霉素+阿莫西林组溃疡愈合率也显著高于对照组。结论选择PPI+克拉霉素+阿莫西林更能有效地根除HP,并可加速溃疡愈合。 相似文献
893.
894.
Y. Oribe M. Fujimura T. Kita N. Katayama M. Nishitsuji J. Hara S. Myou S. Nakao 《Clinical and experimental allergy》2005,35(3):262-267
BACKGROUND: Gastrooesophageal reflux (GER) is a frequent cause of chronic cough. Several investigators have indicated that inhibitors of H(+)K(+)ATPase (proton pump inhibitors; PPIs) could relieve coughing via inhibition of acid reflux. However, we considered that PPIs might directly inhibit increased cough reflex sensitivity. OBJECTIVE: The present study was designed to examine whether PPIs directly inhibit antigen-induced increase in cough reflex sensitivity and to elucidate the mechanism. METHODS: Actively sensitized guinea-pigs were challenged with aerosol antigen (ovalbumin, OVA) and cough reflex sensitivity to inhaled capsaicin was measured 24 h later. The PPIs (omeprazole and rabeprazole) or the histamine H(2) blocker cimetidine were administered intraperitoneally 1 h before OVA challenge and before measuring cough reflex sensitivity, then bronchoalveolar lavage fluid (BALF) was immediately collected. The pH of the fluid obtained by bronchial washing was determined after examining the effect of rabeprazole on the cough response to capsaicin. RESULTS: The number of coughs elicited by capsaicin was significantly increased 24 h after challenge with OVA compared with saline, indicating antigen-induced increase in cough reflex sensitivity. Both PPIs dose dependently and significantly inhibited antigen-induced cough hypersensitivity. Omeprazole did not influence the antigen-induced increase in the total number of cells or ratio (%) of eosinophils in BALF. Cimetidine did not affect the antigen-induced cough hypersensitivity or cellular components of BALF. The pH of the bronchial washing fluid was significantly decreased in antigen-challenged animals. Rabeprazole did not affect the antigen-induced decrease in the pH of bronchial washing fluid. CONCLUSION: These findings show that PPIs, but not histamine H(2) blockers, can directly decrease antigen-induced cough reflex hypersensitivity, while the mechanism remains unclear. 相似文献
895.
非体外循环冠状动脉旁路移植术的血流动力学研究 总被引:15,自引:0,他引:15
目的:分析非体外循环冠状动脉旁路移植术中血流动力学的变化。方法:2000年6月至2001年1月,连续32例病人接受非体外循环冠状动脉旁路移植术,术中、术后对各吻合血管的血流动力学指标进行持续监测。全组完成前降支吻合32例、右冠状动脉26例、回旋支28例、对角支8例。结果:本组死亡例。行前降支冠状动脉吻合时血流动力学指标无明显变化。右冠状动脉吻合时影响右心功能。回旋支及对角支冠状动脉吻合时对血流动力学有明显的影响,导致平均肺动脉压(MPAP)、肺毛细血管楔压(PAWP)、中心静脉压(CVP)明显升高,每搏指数(SVI)及左室每搏功指数(LVSWI)有明显下降;心排指数(CI)有一定的下降趋势。行主动脉近心端吻合时尽管已无心脏搬动,但MPAP、SVRI及肺循环阻力指数(PVRI)仍较诱导后有明显升高,CI有明显下降。术毕及术的2、6、16h各血流动力学指标趋于正常,CI有明显改善。结论:非体外循环冠状动脉旁路移植行前降支及右冠状动脉吻合时对血流动力学影响较小,回旋支及对角支冠状动脉吻合时对血流动力学有明显的影响,术毕及术后2、6、16h各血流动力学指标趋于正常,心脏功能有明显改善。 相似文献
896.
897.
Advances in endourology have made transluminal balloon dilatation a safe and effective procedure for the treatment of ureteral strictures. Bilateral ureteral stricture was treated with retrograde balloon dilatation and ureteral stenting in a 59-year-old-woman. The patient had previously undergone abdominoperineal resection and adjuvant radiotherapy due to rectosigmoid adenocarcinoma. Subsequently, unilateral ureteroenteric fistula was detected on follow-up retrograde ureteropyelography. To our knowledge, this is the first case of ureteroenteric fistula after balloon dilatation for ureteral stricture in a patient with predisposing factors for compromised vascularity of the ureter. 相似文献
898.
899.
A Heat Transfer Model of Thermal Balloon Endometrial Ablation 总被引:3,自引:1,他引:2
A heat transfer model was developed for thermal balloon endometrial ablation treatment for menorrhagia. The model includes heat conduction through the uterus wall, cooling due to blood perfusion through the uterine tissue and the contribution of metabolic heat generation. A parameter sensitivity study indicated that metabolic heat generation had a minimal effect, but model predictions were sensitive to blood perfusion rate. However, within the range of expected perfusion rates, the model calculates damage depths (3–6 mm) close to the range for effective treatment. Using a blood perfusion rate of 0.0028 m
t
3
m
b
-3
s
s
-1
the predicted burn depth (4 mm) correlated well with experimental measurements (4.2 ± 0.6 mm) reported elsewhere for a treatment temperature of 92°C and time of 6 mins (Neuwirth, R. S. et al. The endometrial ablator: A new instrument. Obstet. Gynecol. 83:792–796, 1994). If no vaporization of water in the tissue occurs, the model predicts that the same burn depth of 4 mm can be obtained with increased treatment temperature (130°C) and shorter treatment time (1.4 min). Steeper temperature profiles through the uterine wall suggest that, in the absence of other changes due to higher temperatures, the deeper layers of the myometrium and the serosa would be protected from thermal damage when using higher treatment temperatures for a shorter duration. However, if vaporization occurs at 105°C, the model predicts little benefit in using treatment temperatures above 120°C up to 160°C. For further validation of the model, in vivo studies using the high temperature treatments are needed to measure temperature profiles through the uterine wall, blood perfusion rates, and the other effects of temperature on uterine tissue. © 2001 Biomedical Engineering Society.
PAC01: 8719Pp, 8710+e, 8780-y, 8719Tt 相似文献
900.
S. Raghunandhan Srividya Prashanth Kiran Natarajan R. S. Anand Kumar Mohan Kameswaran 《Indian journal of otolaryngology and head and neck surgery》2009,61(2):99-104
The surgical management of sinusitis was revolutionized worldwide with the advent of the rigid Hopkins rod nasal endoscopes
three decades ago. The traditional Messerklinger technique, was thus propagated worldwide by Prof. Stammberger, from the University
of Graz in Austria and has come into vogue as functional endoscopic sinus surgery (FESS). The principal aim behind this procedure
was the maximal preservation of the nasal mucosal integrity, while providing optimal disease clearance. Today, the introduction
of a new technological innovation called ‘balloon sinuplasty’, has taken the field of sinus surgery a step further. This new
technology is very similar to the principles of balloon angioplasty and today, this system has added an efficient, non-invasive
tool in the armamentarium of the innovative endoscopic rhinologist. This FDA approved technique, in recent times has provided
excellent results in various centers across the western world. We share our first surgical experience with the introduction
of this cutting-edge technology in India. 相似文献