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61.
腰椎节段形态对峡部、小关节应力及小关节接触力影响的有限元分析 总被引:1,自引:0,他引:1
目的:探讨腰椎形态结构变化对峡部裂性滑脱及小关节退变的作用和意义。方法:采用改良的“非种子区域分割方法”及非平行“最佳切割平面”等一系列新型计算机辅助设计(CAD)方法精确建立包括椎间盘高度、腰椎小关节角、椎间盘前凸角改变的L4~L5活动节段有限元模型;在2700N轴向压缩载荷条件下,分别对各有限元模型的峡部、小关节应力、小关节接触力以及椎间盘负载进行测试。结果:压缩载荷下,腰椎活动节段峡部、小关节等效应力及小关节接触力随椎间盘高度的减小而减小,随小关节角的增大而增加,随椎间盘前凸角的增加而减小。结论:椎间盘高度、腰椎小关节角、椎间盘前凸角等形态结构变化对腰椎节段有限元模型的峡部、小关节应力及小关节接触力有明显的影响。提示腰椎峡部应力性骨折及小关节退变的发生与椎间盘高度、腰椎小关节角、椎间盘前凸角等解剖形态因素有关。 相似文献
62.
Lin Bo Wang Jian Guo Shen Li Feng Dong Chao Yang Xu Wen Jun Chen Shu Duo Xie Xiang Yang Song Ning Dai Xiao Ming Yuan 《Journal of gastrointestinal surgery》2008,12(8):1359-1363
We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study
was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness
for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively
evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When
pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic
local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early
gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had
SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic
local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative
procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric
cancer. 相似文献
63.
Eric Racine Marie-Josée Dion Christine A. C. Wijman Judy Illes Maarten G. Lansberg 《Neurocritical care》2009,11(3):345-352
Background
Advances in intensive care medicine have increased survival rates of patients with critical neurological conditions. The focus of prognostication for such patients is therefore shifting from predicting chances of survival to meaningful neurological recovery. This study assessed the variability in long-term outcome predictions among physicians and aimed to identify factors that may account for this variability. 相似文献64.
背景:与小肠黏膜下层等材料相比,脱细胞血管具有天然管状结构,与输尿管形态结构相近,替代输尿管时仅需端端吻合即可,手术操作简单,血管外壁光滑,获取及制备方法简便等优点。
目的:拟应用同种颈动脉血管无细胞基质体外构建输尿管。
设计、时间及地点:观察性实验,于2006-09/2008-06在上海交通大学医学院附属新华医院动物实验中心完成。
材料:长风杂交白猪由上海松联实验动物公司提供。上海交通大学医学院实验动物中心提供的健康成年大鼠8只,用于血管无细胞基质的动物毒性实验。
方法:剥去猪颈动脉血管外膜,PBS冲洗若干遍,然后将血管置于pH 7.1 的PBS中4 ℃下振荡清洗,0.5%十二烷基硫酸钠振荡24 h,后使用双蒸水4 ℃下反复振荡洗涤1周,每日换双蒸水2次。对于解剖过程中肌肉残留相对稍多的血管,在双蒸水洗涤前以混合消化液37 ℃下振荡消化约2 h,再行双蒸水洗涤。制备的无细胞基质置于青、链霉素溶液中,4 ℃保存,完成脱细胞支架制备。
主要观察指标:光镜及电镜观察脱细胞后管壁无细胞基质片的主要成分。将同种异体来源内皮祖细胞培养增殖后植入血管无细胞基质,观察细胞生长情况,并进行血管无细胞基质动物毒性实验。拉力实验了解血管无细胞基质材料的收缩性能。
结果:颈动脉血管无细胞基质中已无细胞成分,无细胞基质主要由胶原成分组成。扫描电镜未见该材料表面存在细胞及细胞碎片,同时发现该无细胞基质存在孔隙样结构。体外同种异体来源的内皮祖细胞培养增殖后植入血管无细胞基质,细胞黏附于无细胞基质。血管无细胞基质按毒性分级属于无毒级。拉力实验说明该无细胞基质具有一定的韧性和牵张性。
结论:采用胰酶和十二烷基硫酸钠制备的颈动脉血管无细胞基质材料无细胞残留,具有一定的韧性和牵张性,种植于其中的种子细胞具备一定的生长能力。 相似文献
65.
FDA’S Perspectives on Cardiovascular Devices 总被引:1,自引:0,他引:1
Eric A. Chen Sonna M. Patel-Raman Kathryn O’Callaghan Matthew G. Hillebrenner 《Journal of cardiovascular translational research》2009,2(2):143-146
The Food and Drug Administration (FDA) decision process for approving or clearing medical devices is often determined by a
review of robust clinical data and extensive preclinical testing of the device. The mission statement for the Center for Devices
and Radiological Health (CDRH) is to review the information provided by manufacturers so that it can promote and protect the
health of the public by ensuring the safety and effectiveness of medical devices deemed appropriate for human use (Food, Drug
& Cosmetic Act, §903(b)(1, 2(C)), December 31, 2004; accessed December 17, 2008 ). For high-risk devices, such as ventricular assist devices (VADs), mechanical heart valves, stents, cardiac resynchronization
therapy (CRT) devices, pacemakers, and defibrillators, the determination is based on FDA’s review of extensive preclinical
bench and animal testing followed by use of the device in a clinical trial in humans. These clinical trials allow the manufacturer
to evaluate a device in the intended use population. FDA reviews the data from the clinical trial to determine if the device
performed as predicted and the clinical benefits outweigh the risks. This article reviews the regulatory framework for different
marketing applications related to cardiovascular devices and describes the process of obtaining approval to study a cardiovascular
device in a U.S. clinical trial. 相似文献
66.
100例性病患者心理健康状况调查分析 总被引:3,自引:1,他引:2
目的:探讨性病患者的心理健康状况,为临床治疗和护理提供依据。方法:采用症状自评量表(SCL-90)对100例性病患者的心理健康状况进行测验。结果:100例性病患者SCL-90检测的阳性率为51%,阳性样本因子分居前的是敌对、强迫症状、抑郁、人际敏感。结论:性病患者广泛存在的心理问题,在药用治疗的同时应注意心理方面的治疗和疏导。 相似文献
67.
Eric Y. T. Chan Daniel K. Ng Chung-hong Chan Ka-li Kwok Pok-yu Chow Josephine M. Cheung Suk-yu Leung 《Sleep & breathing》2009,13(1):59-63
Background and objective The purpose of this study is to assess whether Chinese children with high apnea–hypopnea index (AHI) are sleepier by a modified Epworth Sleepiness Scale (ESS).
Materials and methods Records were retrospectively reviewed. We included children who were between 3 and 12 years old, admitted for overnight polysomnogram
because of suspected obstructive sleep apnea syndrome (OSAS). A modified ESS was used to assess excessive daytime sleepiness
(EDS) of the children.
Results One hundred ninety-two Chinese children were included. Children with high AHI, defined as AHI > 5.0, were sleepier than children with AHI less than or equal
to 5. After adjustment by age, gender, and obesity, children with high AHI remained significantly sleepier. Modified ESS was
significantly correlated with AHI (rho = 0.124, 95% CI = 0.004–0.281). Modified ESS score of >8 was the best cutoff point
with the sensitivity and specificity of 0.29 and 0.91, respectively. The odds ratio of children with modified ESS > 10 having
high AHI was 4.231 (95%CI = 1.248 to 14.338) and children with modified ESS > 8 had the highest odds ratio, 4.295(95%CI = 1.66
to 11.1), of having high AHI.
Conclusion
Chinese children with high AHI appear to be sleepier than children with low AHI. Children with suspected OSAS and high modified ESS,
i.e., ESS > 8, had significantly higher odds ratio of having high AHI. Increased sleepiness is a specific but not a sensitive
symptom in snoring children with high AHI. Screening for EDS in snoring children may help us identify those with high AHI
and prioritize the management of those children.
All authors worked and the study was carried out in Kwong Wah Hospital in Hong Kong. There was no conflict of interest and
no specific source of funding for the study. 相似文献
68.
69.
A case of untreated fusarial onychomycosis leading to serious consequences is reported. Fusarium solani is a widespread fungus and an occasional human pathogen. It usually invades rapidly in immunocompromised hosts, and often results in a poor outcome despite treatment. We report a woman with diabetes mellitus who had untreated fusarial infection of the nails, which developed into subcutaneous fusariosis, superinfected by bacteria, and then evolved into osteomyelitis that subsequently resulted in septic shock. Early management of mycotic nails in immunocompromised hosts is crucial to prevent life‐threatening disease. 相似文献
70.
Jing‐Ping Zhang Limin Zheng Jiang‐Hai Wang Karl‐Eric Magnusson Xin Liu 《Phytotherapy research : PTR》2009,23(6):844-850
Ganoderma sinensis has been used widely in Oriental countries for the prevention and treatment of various diseases including cancer. Previous studies have shown that the lipid extract from Ganoderma exhibits direct cytotoxicity against tumor cells. Here, it is reported that the lipid extract from germinating G. sinensis spores, at lower concentrations that have no direct tumoricidal activity, induce potent antitumor immune responses in human monocytes/macrophages. Upon stimulation with the lipid extract, monocytes/macrophages exhibited markedly increased production of proinflammatory cytokines and surface expression of costimulatory molecules. Conditioned medium from stimulated cells effectively suppressed the growth of tumor cells. Apparently, the lipid extract triggered macrophage activation via a mechanism different from that associated with LPS. Moreover, it was observed that the lipid extract could partially re‐establish the antitumor activity of the immunosuppressive tumor‐associated macrophages. These results indicated that in addition to its direct tumoricidal activity, the lipid extract from G. sinensis spores could exert antitumor activity by stimulating the activation of human monocytes/macrophages. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献