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101.
Tissue engineering is an application for gene therapy that is in its infancy. We show that simple liposomal-mediated gene transfer could result in a potentially useful biological effect in the field of wound healing. cDNA encoding the 165 amino acid form of vascular endothelial growth factor complexed to commercially available liposomes was injected into rat skin 1 week before raising a random pattern 3 x 10 cm flap. The flap survival was enhanced by 14 percent, and was accomplished without accessing the arterial inflow of the territory. These results were statistically significant (p<0.002) and reproducible. No adverse effects were seen. Histological analysis of the angiogenesis localized much of the new vessel formation to the area around the hair follicles. Polymerase chain reaction amplification of extracted flap tissue confirmed the presence of the transgene.  相似文献   
102.
103.
Insulin-like growth factor-1 (Igf-1), a critical mediator of tissue repair, is significantly decreased in diabetic wounds. Furthermore, decreased levels of hypoxia-inducible factor 1-alpha (Hif-1alpha) and its target genes are also associated with impaired wound healing in diabetic mice. The aim of our study was to examine whether the reduced levels of Igf-1 are responsible for the reduction in Hif-1alpha protein synthesis and activity in diabetic wounds. We provide evidence that Igf-1 regulates Hif-1alpha protein synthesis and activity during wound repair. In addition, Igf-1 stimulated phosphytidylinositol 3-kinase activity in diabetic fibroblasts, which, in turn, increased activation of the translational regulatory protein, p70 S6 kinase. Moreover, improved healing of diabetic wounds by addition of recombinant IGF-1 protein was associated with an increase in Hif-1alpha protein synthesis and function in vivo.  相似文献   
104.
目的:本研究的目的是观察注射疗法及复合小针刀疗法治疗肌筋膜疼痛综合征对自主神经系统功能的影响。方法:选择40例诊断明确的肌筋膜疼痛病人,随机分为两组,每组20例。Ⅰ组:采用注射疗法治疗;IS组:采用注射疗法加小针刀治疗。观察两组病人治疗前后心率变异(HRV)的频域变化,低频LF、超低频LLF、高频HF、低高频比LF/HF及心率变异指数HR-Ⅵ;用视觉模拟评分法(VAS)评定治疗前后疗效并随访观察其远期疗效。结果:①HRV频域指标组内比较:LF、LLF、HF以及HRVI治疗前舆治疗后1min比较有显着性差异(P〈0.05),与5min、10min比较有非常显着性差异(P〈0.01)。LF/HF治疗前与治疗后5min、10min比较有显着性差异(P〈0.05)。组间治疗后1、5、10min,两两比较无显着性差异。②组间比较:病人治疗后临床症状、VAS评分均较治疗前降低.治疗前后IS组有非常显着性差异(P〈0.01)。两组VAS降低率有非常显着性差异(P〈0.01)。③回访病例中,两组治疗有效率比较有显着性差异(P〈0.05)。结论:注射疗法以及复合小针刀疗法均可有效改善肌筋膜疼痛病人的自主神经功能,其机制可能是通过调节、稳定自主神经系统功能达到缓解疼痛。注射疗法复合小针刀疗法的远期疗效优于单纯注射疗法。  相似文献   
105.
Background: The authors determined whether desflurane altered myocardial excitation-contraction coupling and electrophysiologic behavior in the same manner as isoflurane and sevoflurane.

Methods: The effects of desflurane on isometric force in guinea pig ventricular papillary muscles were studied in modified standard and in 26 mm K+ Tyrode solution with 0.1 [mu]m isoproterenol. Desflurane effects on sarcoplasmic reticulum Ca2+ release were also determined by examining its actions on rat papillary muscles, guinea pig papillary muscles in low-Na+ Tyrode solution, and rapid cooling contractures. Normal and slow action potentials were recorded using a conventional microelectrode technique. Ca2+ and K+ currents of guinea pig ventricular myocytes were examined.

Results: Desflurane (5.3% and 11.6%) decreased peak force to approximately 70% and 40% of the baseline, respectively, similar to the effects of equianesthetic isoflurane concentrations. With isoproterenol in 26 mm K+ Tyrode solution, desflurane markedly depressed late peaking force and modestly depressed early peak force. The rested state contractions of rat myocardium or guinea pig myocardium in low-Na+ Tyrode solution were modestly depressed, whereas rapid cooling contractures were virtually abolished after desflurane administration. Desflurane significantly prolonged the action potential duration. Desflurane reduced L-type Ca2+ current and the delayed outward K+ current but did not alter the inward rectifier K+ current.  相似文献   

106.
Vascular 18F-FDG uptake marker represents inflammation in atherosclerotic lesions, but whether inflammation can be reversed by risk-modifying interventions has not, to our knowledge, been demonstrated. In this study, we evaluated the change of vascular 18F-FDG uptake in response to lifestyle intervention on serial PET/CT scans and further assessed how the findings relate to atherogenic risk reduction. METHODS: A total of 60 healthy adults underwent 18F-FDG PET/CT scans and atherogenic risk-factor assessment at baseline and again after 17.1 +/- 8.3 mo of practicing lifestyle modification. The PET/CT images were evaluated for the presence of vascular 18F-FDG lesions, and vessel-to-blood-pool 18F-FDG ratios were measured. Indices from summed ratios of positive lesions were compared and correlated to atherogenic risk factors. RESULTS: At follow-up, significant reductions in diastolic blood pressure (P < 0.05), total cholesterol (P < 0.05), and low-density lipoprotein level (P < 0.05) and an increase in high-density lipoprotein (HDL) level (P < 0.0001) were demonstrated. On the initial PET/CT scan, 50 of 60 subjects showed 1 or more 18F-FDG-positive lesions (5.9 +/- 5.0/subject), leading to a total of 352 vascular sites. On follow-up, 18F-FDG-positive lesions were significantly reduced to 2.1 +/- 2.2 sites per subject (P < 0.0001) and a total of 124 sites (64.8% reduction). Follow-up 18F-FDG-positive rates were significantly reduced for the aorta and iliac arteries. In addition, significant reductions in the whole-body 18F-FDG index from 1.39 +/- 1.23 to 0.53 +/- 0.59 (P < 0.0001) and carotid 18F-FDG index from 0.08 +/- 0.16 to 0.03 +/- 0.06 (P = 0.01) were shown. The whole-body 18F-FDG index correlated with total cholesterol (P < 0.05) and HDL level (P < 0.05), and the magnitude of reduction in the 18F-FDG index closely correlated to the amount of increase in plasma HDL level (P = 0.005). CONCLUSION: Our study demonstrated that vascular 18F-FDG uptake is reversed in response to atherogenic risk reduction by lifestyle intervention and that the magnitude of improvement correlates to increases in plasma HDL levels. Thus, serial 18F-FDG PET/CT may be useful for monitoring improvements in the inflammatory component of atherosclerotic lesions in response to risk modification.  相似文献   
107.
Cooking processes that gelatinize granules or disrupt structure might increase the glucose and insulin responses because a disruption of the structure of starch by gelatinization increases its availability for digestion and absorption in the small intestine. We hypothesized that the uncooked form of rice, which has a relatively low degree of gelatinization even though in powder form, would result in lower metabolic glucose and insulin responses compared with cooked rice (CR). To assess the effects of the gelatinization of rice on metabolic response of glucose and insulin, we investigated the glucose and insulin responses to 3 rice meals of different gelatinization degree in female college students (n = 12): CR (76.9% gelatinized), uncooked rice powder (UP; 3.5% gelatinized), and uncooked freeze-dried rice powder (UFP; 5.4% gelatinized). Uncooked rice powders (UP and UFP) induced lower glucose and insulin responses compared with CR. The relatively low gelatinization degree of UPs resulted in low metabolic responses in terms of the glycemic index (CR: 72.4% vs UP: 49.7%, UFP: 59.8%) and insulin index (CR: 94.8% vs UP: 74.4%, UFP: 68.0%). In summary, UPs that were less gelatinized than CR induced low postprandial glucose and insulin responses.  相似文献   
108.
COPD机械通气病人下呼吸道感染致病菌分布特点   总被引:1,自引:0,他引:1  
①目的 探讨慢性阻塞性肺病(COPD)病人机械通气后下呼吸道感染致病菌的特点。②方法 取32例COPD并发呼吸衰竭行机械通气病人下呼吸道分泌物做痰细菌学培养,同时做药物敏感试验。③结果 32例病人共分离出菌株76株,阳性率71.7%,其中混合感染10例次。其中革兰阴性杆菌(GNB)58株,占76.3%;阳性球菌10株,占13.2%;真菌8株,占10.5%。常见致病菌以铜绿假单胞菌、鲍曼不动杆菌和肺炎杆菌为主,GNB中铜绿假单胞菌和不动杆菌的耐药率高。④结论 COPD应用机械通气病人下呼吸道感染以革兰阴性杆菌为主,耐药性高。  相似文献   
109.
大学生心理健康教育干预研究   总被引:11,自引:2,他引:9  
目的 研究高校心理健康干预模式 ,提高大学生心理健康水平。方法 采取分层整群抽样的方法 ,运用SCL - 90自评量表对该院学生测试评分 ,分别进行实施心理健康干预模式 (心理教育、心理预防、心理训练 )前后状况调查 ,比较学生心理测试总体水平。结果 学校心理健康教育干预实施后一年 ,学生心理测试 8项因子分均值低于心理健康干预实施前 ,其中强迫、人际关系、焦虑、恐怖、偏执因子分实施前后有显著性差异 (P <0 0 5 )。结论 学校实施心理健康教育干预能有效地维护大学生心理健康 ,促进大学生心理发展 ,提高大学生心理素质  相似文献   
110.
52例疑为L_(4-5)或L_5~S_1椎间盘突出的患者,同时行选择性腰升静脉造影(SALV)和碘水脊髓造影.43例手术和病理证实46个椎间盘突出.本文对两种检查方法诊断准确性,适应性和并发症进行了比较.临床疑诊为腰椎间盘突出者,脊髓造影可疑或正常,SALV是有诊断价值的.  相似文献   
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