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排序方式: 共有394条查询结果,搜索用时 15 毫秒
71.
S. Portnoy I. Siev-Ner N. Shabshin 《Computer methods in biomechanics and biomedical engineering》2013,16(11):1009-1019
Transtibial amputation prosthetic-users are at risk of developing deep tissue injury (DTI) while donning their prosthesis for prolonged periods; however, no study addresses the mechanical loading of the residuum during sitting with a prosthesis. We combined MRI-based 3D finite element modelling of a residuum with an injury threshold and a muscle damage law to study risks for DTI in one sitting subject in two postures: 30°-knee-flexion vs. 90°-knee-flexion. We recorded skin-socket pressures, used as model boundary conditions. During the 90°-knee-flexion simulations, major internal muscle injuries were predicted (>1000 mm3). In contrast, the 30°-knee-flexion simulations only produced minor injury ( < 14 mm3). Predicted injury rates at 90°-knee-flexion were over one order of magnitude higher than those at 30°-knee-flexion. We concluded that in this particular subject, prolonged 90°-knee-flexion sitting theoretically endangers muscle viability in the residuum. By expanding the studies to large subject groups, this research approach can support development of guidelines for DTI prevention in prosthetic-users. 相似文献
72.
大鼠脑内5-羟色胺在应激性溃疡形成中的作用 总被引:9,自引:0,他引:9
通过神经化学和神经药理学的方法,在大鼠观察了冷冻加束缚应激性溃疡的形成过程中,脑内5-羟色胺(5-HT)的作用。结果如下:1.在应激过程中,脑内5-HT 及其主要代谢产物5-羟吲哚乙酸(5-HIAA)的含量明显升高,特别是5-HIAA 的含量随着应激时间的延长持续上升,说明5-HT 的代谢加快。2.脑内5-HT 或5-HIAA 含量在应激45min 时与溃疡指数呈明显的负相关,而在应激180min 时则与溃疡指数呈明显的正相关。3.侧脑室注射5-HT或其前体5-羟色氨酸(5-HTP),对应激性溃疡的形成呈双重作用,小剂量时减轻而大剂量时加重溃疡的形成。4.腹腔注射5-HT 合成阻断剂对氯苯丙氨酸(pCPA)可降低大鼠脑内5-HT 和5-HIAA 含量,使应激60min 鼠的溃疡形成加重,而使应激180min 鼠的溃疡形成减轻。以上结果提示,在大鼠的冷冻加束缚应激性溃疡的形成过程中,脑内5-HT 起着一定的作用,它很可能在应激早期减轻而在应激晚期加重溃疡的形成。 相似文献
73.
Hydrogen gas inhalation protects against cutaneous ischaemia/reperfusion injury in a mouse model of pressure ulcer 下载免费PDF全文
Wei Fang Guizhen Wang Luyan Tang Huilin Su Huyan Chen Wanqing Liao Jinhua Xu 《Journal of cellular and molecular medicine》2018,22(9):4243-4252
Pressure ulcer formation depends on various factors among which repetitive ischaemia/reperfusion(I/R) injury plays a vital role. Molecular hydrogen (H2) was reported to have protective effects on I/R injuries of various internal organs. In this study, we investigated the effects of H2 inhalation on pressure ulcer and the underlying mechanisms. H2 inhalation significantly reduced wound area, 8‐oxo‐dG level (oxidative DNA damage) and cell apoptosis rates in skin lesions. H2 remarkably decreased ROS accumulation and enhanced antioxidant enzymes activities by up‐regulating expression of Nrf2 and its downstream components in wound tissue and/or H2O2‐treated endothelia. Meanwhile, H2 inhibited the overexpression of MCP‐1, E‐selectin, P‐selectin and ICAM‐1 in oxidant‐induced endothelia and reduced inflammatory cells infiltration and proinflammatory cytokines (TNF‐α, IL‐1, IL‐6 and IL‐8) production in the wound. Furthermore, H2 promoted the expression of pro‐healing factors (IL‐22, TGF‐β, VEGF and IGF1) and inhibited the production of MMP9 in wound tissue in parallel with acceleration of cutaneous collagen synthesis. Taken together, these data indicated that H2 inhalation suppressed the formation of pressure ulcer in a mouse model. Molecular hydrogen has potentials as a novel and alternative therapy for severe pressure ulcer. The therapeutic effects of molecular hydrogen might be related to its antioxidant, anti‐inflammatory, pro‐healing actions. 相似文献
74.
Chinnamaruthu Jayachitra Senguttuvan Jamuna Mohammad Ajmal Ali Subramaniam Paulsamy Fahad M.A. Al-Hemaid 《Saudi Journal of Biological Sciences》2018,25(2):293-297
Cissus setosa is an indigenous medicinal herb commonly used for the treatment of gastro ulcers. In the current investigation the aerial methanolic extract of C. setosa was investigated for their antiulcer activity using pylorus ligation and ethanol in experimental rats. The extract was administered at the doses of 200 and 400 mg/kg b.w. orally for 3 days. However, higher dose of the extract subsequently reduced gastric ulcer induced aberrations by pylorus ligation (70.05%) and ethanol (78.16%) as judged by their altered biochemical parameters such as free acidity, total acidity, total carbohydrate, total protein and pepsin activity. Furthermore, macroscopic examination of rat’s stomach also showed that the pretreatment with methanolic extract notably lowered the pylorus ligation and ethanol induced ulcers. As perceived in the present study, evidently, our findings basically supports the potency of the methanol extracts of C. setosa to treat gastrointestinal related disorders, thus lends pharmacological credence to the suggested folklore use. 相似文献
75.
Diminished circulating concentration of interleukin‐35 in Helicobacter pylori‐infected patients with peptic ulcer: Its association with FOXP3 gene polymorphism,bacterial virulence factor CagA,and gender of patients 下载免费PDF全文
76.
目的:分析艾司美拉唑治疗胃溃疡患者成本效果的影响因素。方法:回顾性分析2014年9月-2018年1月我院诊治的胃溃疡患者220例的临床病例资料,根据治疗药物的不同分为观察组120例与对照组100例,对照组给予奥美拉唑+克拉霉素+阿莫西林治疗,观察组给予艾司美拉唑+克拉霉素+阿莫西林,两组均持续治疗观察2周,对比两组治疗成本、治疗效果、不良反应的发生情况和成本效果,以及影响艾司美拉唑治疗胃溃疡患者成本效果的因素。结果:观察组与对照组患者完成治疗周期的成本费用分别为567.14±48.23元、551.49±45.61元,两组比较差异无统计学意义(P0.05)。观察组与对照组的治疗总有效率分别为95.83%(115/120)和82.00%(82/100),观察组显著高于对照组(P0.05)。观察组与对照组治疗期间的腹胀、便秘、恶心、口腔异味等不良反应发生率为8.33%(10/120)和11.00%(11/100),对比差异无统计学意义(P0.05)。观察组C/E与ΔC/E值均显著低于对照组(P0.05)。多因素logistic回归分析显示病程、溃疡直径、不良反应为影响艾司美拉唑治疗胃溃疡成本效果的主要因素(P0.05)。结论:艾司美拉唑治疗胃溃疡患者成本效果好,且不会增加不良反应的发生,病程、溃疡直径、不良反应为影响成本效果的主要因素。 相似文献
77.
目的:探讨彩超定位下的腔镜深筋膜下交通支离断术(SEPS)联合湿性换药技术治疗下肢静脉性溃疡(VU)的方法及效果。方法:回顾性分析了8例VU患者共8条C6级下肢SEPS手术联合湿性换药技术的方法和效果。术前用彩色多普勒超声对功能不全交通支(ICPV)行体表定位,进行SEPS+大隐静脉高位结扎剥脱术+硬化剂注射术,术后湿性换药技术溃疡换药。结果:超声准确定位下SEPS联合湿性换药术后所有C6级患肢VU均在短期内愈合,随访期间无溃疡复发。结论:SEPS联合湿性换药技术治疗VU术后安全,疗效确切,并发症少。 相似文献
78.
《Cytokine》2016
Helicobacter pylori (H. pylori) infection is among the most prevalent human infections. CXCL12 is a well-known CXC chemokine involved in inflammation and play major roles in angiogenesis. There is currently very limited data on the role of CXCL12 in peptic ulcer disease. Hence, we aimed to explore whether CXCL12 is involved in the pathogenesis of peptic ulcer induced by H. pylori. In this study, we enrolled 102 H. pylori-infected patients, including 51 with active ulcer (GA) and 51 with healing ulcer (GH). We also recruited 50 healthy subjects as control, which did not show any sign or symptoms of chronic inflammatory diseases, infection, or immune-related disorders. Endoscopy was performed to determine the stage of the disease. ELISA was used for detection of H. pylori infection and CXCL12 measurement. We also employed western blotting to detect CXCL12 in ulcerative lesions of H. pylori. Demographic data were also collected by questionnaire. Our results demonstrated that CXCL12 serum levels in GA group (151.8 ± 18.31 pg/mL) were significantly higher than those in GH (36.89 ± 6.78 pg/mL) and control groups (33.77 ± 9.12 pg/mL) (P < 0.0001). However, we did not observe a significant difference between GH and control groups. Moreover, overexpression of CXCL12 in gastric lesions of patients in GA group was confirmed by Western blot analysis. According to the result of the present study, it could be concluded that CXCL12 is involved in the pathogenesis and healing of H. pylori-induced peptic ulcer. CXCL12 serum levels may also be used to distinguish between GA and GH phases of the disease. 相似文献
79.
目的:探讨三联疗法与胃复春联合治疗幽门螺杆菌(Hp)阳性胃溃疡的临床疗效。方法:选择2011年11月到2014年11月在我院就诊的240例Hp阳性胃溃疡患者,随机分为实验组(n=120)和对照组(n=120)。对照组采用三联疗法,实验组在对照组基础上加服胃复春。比较两组患者的临床疗效、Hp根除率、胃泌素、胃动素水平。结果:实验组患者的总有效率和Hp根除率均明显高于对照组,具有显著性差异(均P0.05)。实验组治疗后胃泌素水平低于治疗前,亦低于对照组治疗后,具有显著性差异(均P0.05),胃动素变化无显著性差异。结论:三联疗法联合胃复春治疗Hp阳性胃溃疡能有效根除Hp,降低胃泌素水平,治疗效果良好。 相似文献
80.
Cleavage of Rabbit Myelin Basic Protein by Pepsin 总被引:13,自引:13,他引:0
Rapid cleavage of bovine and guinea pig myelin basic proteins by pepsin at pH 6.0 is limited to the Phe-Phe bond in the middle of the molecule. In the rabbit protein, however, rapid cleavages occur elsewhere in addition to the Phe87-Phe88 bond in regions in which there are amino acid substitutions. Rapid cleavage occurs at the Leu151-Phe152 bond, at which Ile-151 has been replaced by Leu, the residue that actually contributes the scissile bond. Rapid cleavages occur at the Phe44-Phe45 and Leu109-Ser110 bonds, which in the bovine and guinea pig proteins are relatively resistant under the experimental conditions (pH 6.0). The increased susceptibility of these bonds in the rabbit protein appears to be related to the replacement of Gly-46 by Ser and the change in the sequence immediately NH2-terminal to Leu-109, from Leu-Ser to Thr-Val. These cleavages of the rabbit protein at the four very susceptible bonds have permitted us to isolate peptides (1-44), (45-87), (88-109), (110-151), and (152-168) in high yield. We have also isolated peptides (88-151), (1-14), and (15-44) in low yield; the latter two result from limited cleavage at the relatively resistant Tyr14Leu15 bond. Peptide (88-109) has been chromatographically resolved into species differing in the degree of methylation of Arg-105; this resolution is thought to result from differences in hydrogen bonding ability of the guanidinium groups. 相似文献