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61.
番茄红素与成骨细胞、破骨细胞及骨质疏松症   总被引:1,自引:0,他引:1  
学术背景:骨质疏松症是较易发生的疾病,研究骨质疏松的发病机制寻找治疗骨质疏松的药物是预防老年性骨质疏松症的理想选择。目的:综述近几年来国内外关于氧化应激及番茄红素在骨质疏松发病中的作用的相关研究,为开发预防和治疗骨质骨质疏松的药物提供理论依据。检索策略:应用计算机检索Medline和Science Direct Online数据库1989-01/2007-04期间的相关文章,检索词为"oxidative stress,osteoclast,osteoblast,lycopene,osteoporosis",限定文章语言种类为English。同时计算机检索中国期刊全文数据库2000-01/2007-04期间的相关文章,检索词为"氧化应激,骨质疏松,成骨细胞,破骨细胞,番茄红素",限定文章语言种类为中文。对资料进行初审,选择有关人体内氧化应激形成机制、氧化应激与成骨细胞、氧化应激与破骨细胞、氧化应激与抗氧化剂、番茄红素与成骨细胞及破骨细胞和番茄红素与骨质疏松症关系的最新进展文献,共收集到121篇,排除综述类及重复研究。文献评价:符合纳入标准的31篇文献中,5篇涉及骨质疏松症的概述,20篇涉及氧化应激和抗氧化剂在骨质疏松症发病中作用的相关研究,6篇涉及番茄红素与氧化应激、成骨细胞、破骨细胞及绝经后骨质疏松关系的相关研究。资料综合:氧化应激是骨质疏松发病的一个危险因素。氧化应激不但作用于成骨细胞还作用于破骨细胞。国内外学者对于番茄红素的抗氧化性能研究取得了很大进展,已通过细胞培养观察到其对成骨细胞和破骨细胞均有作用,通过临床研究发现,番茄红素通过其抗氧化功能而影响成骨细胞和破骨细胞的功能,从而能够对骨质疏松症发生发展的病理过程进行有效干预,最终阻止和减缓骨质疏松症的发生。结论:番茄红素具有的抗氧化功能使其在骨质疏松的预防及治疗方面起着重要的作用。  相似文献   
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Abdominal surgery has traditionally been performed through large incisions into the peritoneal cavity. In the past decade, traditional open surgery has been increasingly replaced by minimally invasive laparoscopic and robotic techniques. In comparison to open surgery, these approaches can decrease postoperative pain, shorten the convalescence period, and improve cosmesis. Nonetheless, these techniques require multiple small entry incisions and are therefore associated with risk of wound infection and incisional hernia. The latest surgical advance is performance of procedures via natural body openings such as the mouth, anus, vagina, and bladder. To date, clinical experience with natural orifice translumenal endoscopic surgery (NOTES) is extremely limited. Herein, we describe the initial clinical case in which we evaluated the bladder as a portal for NOTES. Our experience indicates clinical feasibility of transvesical peritoneoscopy with existing clinical equipment, but additional refinements of the technique and associated instrumentation appear warranted. In comparison to other portals, the urinary tract seems to have distinct clinical advantages for NOTES.  相似文献   
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Background

Cystoscopy remains one of the most important diagnostic procedures for the lower urinary tract. Wireless capsule endoscopy was introduced in the 1990s but use to date is limited to gastroenterology.

Objective

We evaluated the feasibility in the pig model of using wireless capsule endoscopes (WCEs) for cystoscopy.

Design, setting, and participants

Experimental evaluation of capsule cystoscopy was performed in a 50-kg farm pig. The capsule was deployed into the bladder through a custom access sheath. Images were continuously transmitted at a rate of four frames per second to a laptop computer and processed using proprietary software. Manipulation of the WCE within the bladder was performed using a set protocol. The animal was then euthanized and gross inspection was performed.

Measurements

We measured the ability to deploy and manipulate the capsule within the bladder. Feasibility of capturing and retrieving images in real time was also assessed.

Results and limitations

The WCE was efficiently deployed and manipulated within the bladder passively and with the use of external magnets. The entire bladder mucosa was visualized. Real-time image transmission and capture were successful. No complications were seen during capsule cystoscopy. Minor urethral bleeding was observed after the experiment, likely related to placement of the access sheath required for deployment of the WCE. Limitations are that the evaluation of WCE was performed in the pig model, in only one female animal, using a nonsurvival approach. Furthermore, the study was not designed to differentiate normal from abnormal mucosal findings and focused solely on inspection of the bladder.

Conclusions

This report suggests that cystoscopy with a WCE is feasible. With this device, all aspects of the bladder mucosa could be visualized, and ongoing technologic and procedural developments are warranted for this new approach.  相似文献   
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Advances in robotic prostatectomy   总被引:2,自引:0,他引:2  
Robotic-assisted laparoscopic prostatectomy (RALP) has emerged as an important treatment option for localized prostate cancer. As such, methods to improve instrumentation, technique, outcomes, and cost require continued investigation. For example, a recently introduced four-armed robotic system has limited the need for bedside assistants, while an enhanced understanding of pelvic anatomy as visualized robotically has led to valuable modifications in operative technique. Increased surgeon experience has decreased perioperative morbidity, and has resulted in short-term pathologic and functional outcomes that compare favorably with open radical prostatectomy. Meanwhile, quality-of-life studies using validated instruments are helping to define the time course of patient recovery. Nevertheless, costs associated with robotic surgery remain daunting. As the follow-up of patients treated with RALP matures, future studies, ideally with a prospective, randomized design, will be needed to establish the long-term oncologic efficacy of the procedure and to evaluate the overall advantages of RALP compared with open surgery.  相似文献   
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