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1.
Background: Chronic pain conditions may result from peripheral nerve injury, chronic peripheral inflammation, or sensory ganglia inflammation. However, inflammatory processes may also contribute to peripheral nerve injury responses. To isolate the contribution of local inflammation of sensory ganglia to chronic pain states, the authors previously developed a rat model in which long-lasting pain is induced by inflaming sensory ganglia without injuring the neurons. This results in prolonged mechanical pain, local increases in proinflammatory cytokines, increased neuronal hyperexcitability, and abnormal spontaneous activity.

Methods: The authors used whole cell patch clamp in acutely isolated small-diameter neurons to determine how localized inflammation (3-5 days) of L4 and L5 ganglia altered voltage-gated K+ and Na+ currents.

Results: Tetrodotoxin-sensitive Na+ currents increased twofold to threefold in neurons from inflamed ganglia. Tetrodotoxin-resistant Na+ currents increased more than twofold, but only in cells that bound isolectin B4. These increases occurred without shifts in voltage dependence of activation and inactivation. Similar results are seen in models of peripheral inflammation, except for the large magnitudes. Unlike most pain models, localized inflammation increased rather than decreased voltage-gated K+ currents, due to increased amplitudes of the sustained (delayed rectifier) and fast-inactivating transient components. The overall effect in current clamp experiments was an increase in excitability as indicated by decreased rheobase and lower action potential threshold.  相似文献   

2.
促甲状腺素及其受体与骨质疏松关系的研究进展   总被引:1,自引:0,他引:1       下载免费PDF全文
骨质疏松症(OP)是严重威胁老年人身心健康的常见疾病。随着人口老年化,老年性骨质疏松症发病率逐年增加。近年来内分泌性骨质疏松日见增多,促甲状腺激素(TSH)及促甲状腺激素受体(TSHR)与骨量减少、骨质疏松的关系倍受关注。成骨细胞和破骨细胞上的促甲状腺激素受体的作用是造成这一作用的关键。而此过程还会受到2型碘化甲腺氨酸脱碘酶、肿瘤坏死因子(TNF)等的影响。同时促甲状腺激素受体存在基因多态性,对其功能存在不同程度的影响,也可能是造成骨质疏松的重要原因。通过对这个领域的深入研究为内分泌性骨质疏松的防治提供依据。  相似文献   
3.
Background: Chronic pain models are commonly defined as either nerve-injury or inflammation models, but recent work suggests inflammatory processes are important in nerve injury-induced pain.

Methods: In the rat spinal nerve ligation model, the authors examined effects of systemic corticosteroid triamcinolone acetonide (TA) on the cytokine protein profile and sympathetic sprouting in the axotomized sensory ganglia, excitability of sensory neurons, and mechanical sensitivity.

Results: By postoperative day 3, marked increases (5- to 16-fold) in monocyte chemoattractant protein-1, growth-related oncogene (GRO/KC or CXCL1), and interleukin (IL)-6 were observed, whereas IL-4 and IL-2 levels fell more than fourfold. The increased cytokines and number of sympathetic basket formations in the sensory ganglia were reduced toward normal values by TA given starting at the time of injury. Interleukin-4 and IL-2 levels were not restored by TA. Systemic TA also reduced the firing rate and incidence of bursting activity, but not the overall incidence of spontaneous activity, in large- and medium-sized neurons. Mechanical hypersensitivity on postoperative day 3 was reduced by TA, and some effect could still be observed 4 days after cessation of TA. However, starting TA at day 7 was ineffective.  相似文献   

4.
目的 探讨互动微信群结合病例教学(case-based learning,CBL)在血管外科见习教学中的应用效果。方法 对随机分组的128名在血管外科临床见习的7年制学生分别实施互动微信群结合CBL(试验组)和单纯CBL(对照组);用统一的考核方法评估两组学生接受专业理论及临床知识的情况,评价两种教学在血管外科见习中的教学效果。用SPSS 22.0进行t检验。结果 试验组的理论考试成绩为(86.36±7.42)分,临床考试成绩为(88.44±7.62)分,高于对照组的(84.71±6.72)分和(86.22±6.41)分;试验组学生在学习兴趣、课堂气氛、自学能力、临床思维和团队精神共5方面的满意度也高于对照组。结论 互动微信群结合CBL能提高血管外科临床见习的教学效果,提高学生的自学能力及临床思维能力。  相似文献   
5.

In this study, exposure experiments were conducted to assess the effects of polystyrene nanoparticles (PS) and amine-modified polystyrene nanoparticles (APS) at environmental concentrations (1, 10, and 100 µg L??1) on two fungal species (Geotrichum candidum and Aspergillus niger), isolated from leaf litter in streams, concerning their growth and metabolic activity. Results showed that PS at 1 and 10 µg L??1 have hormesis effects on G. candidum growth. Compared with G. candidum, A. niger had higher sensitivity to nanoplastic exposure. Besides, the peroxidase and cellobiohydrolase activities of A. niger were significantly inhibited by nanoplastics (except 1 µg L??1 PS), which would weaken its metabolic activity in carbon cycling. These results provided a new thought on how the growth and functions of aquatic fungi cope with the stress induced by nanoplastics. Overall, the study provided evidence for the different responses of aquatic fungi to nanoplastics in streams.

  相似文献   
6.
4-氯正丁酸乙酯和甘氨酰胺盐酸盐以无水乙醇为溶剂,在碳酸氢钠存在下,加热回流反应20 h,最后经异丙醇重结晶制得中枢兴奋剂吡拉西坦,收率约58%,纯度99.6%.  相似文献   
7.
We sought to investigate the impact of full annuloplasty rings versus C-shape bands on mitral annular geometry in the presence of fibroelastic deficiency (FED), as assessed by intraoperative three-dimensional transesophageal echocardiography (3DTEE). We retrospectively selected 65 patients who underwent mitral valve repair for severe mitral regurgitation caused by FED using full rings (the Ring group, n?=?30) and C-shape bands (the Band group, n?=?35). 71 controls without valvular heart disease were also included. Thorough 3DTEE inspections were performed for the entire cohort to measure morphological parameters of mitral annulus before and after surgery. Mid-term repair durability and left atrial diameter were followed up. The preoperative 3DTEE parameters, including annular diameters, area, height and aorto–mitral angle, were significantly larger in the FED groups than normal, and were comparable between two groups using different annuloplasty devices. After repair, the anterior–posterior diameter, annulus circumference and area were significantly larger in the Band group than in the Ring group. The aorto–mitral angle became comparable with normal value in the Ring group (p?=?0.728), but not in the Band group (p?=?0.011). Follow-up echocardiographic data showed a significant correlation between postoperative aorto–mitral angle and reduced left atrial diameter at 50.3 months after surgery (r?=?0.63; p?<?0.001). In conclusion, compared with C-shape bands, full rings may impose less narrowing on aorto–mitral angle, which correlates well with mid-term left atrial reverse remodeling.  相似文献   
8.
股骨干骨折为临床上常见骨折,因其解剖的特殊性,骨折后往往移位明显。股骨干为下肢主要负重骨之一,治疗不当容易出现畸形、功能障碍。股骨干骨折的治疗方法有多种,包括非手术治疗和手术治疗,其主要目的是恢复股骨正常的力线和长度,不同治疗方法各有利弊。本文主要介绍股骨干骨折治疗的研究进展。  相似文献   
9.
目的探讨“中国早期胃癌筛查流程专家共识意见”在广东地区胃癌风险人群中的应用价值。方法纳入2018年3月—2019年3月在广东地区进行早期胃癌筛查的居民,采用量化的新型胃癌筛查评分系统进行胃癌初筛,根据初筛结果将患者分为高危组、中危组和低危组,比较各组精查胃镜下早期胃癌、癌前疾病、癌前病变的检出率,统计学分析采用卡方检验。结果完成精查胃镜检查共545例,其中高危组32例,中危组184例,低危组329例。精查胃镜结果显示,早期胃癌检出率方面,高危组(12.5%)>中危组(1.1%)>低危组(0),差异有统计学意义(χ2=41.85,P<0.01);癌前疾病检出率方面,高危组(60.9%)>中危组(52.4%)>低危组(34.3%),差异有统计学意义(χ2=18.00,P<0.01);癌前病变检出率分别为17.9%、8.8%及8.8%,差异无统计学意义(χ2=2.58,P=0.28)。内镜病变检出阳性率组间比较,高危组(71.9%)>中危组(57.1%)>低危组(40.1%),差异有统计学意义(χ2=21.54,P<0.01)。结论“中国早期胃癌筛查流程专家共识意见”在广东地区胃癌风险人群的早期胃癌及癌前疾病筛查中具有较好的应用价值。  相似文献   
10.
电压门控氯通道是表达于细胞膜或细胞器质膜上的一类阴离子跨膜通道蛋白,具有调节细胞容积、参与细胞迁移、增殖与凋亡以及氧化应激等生物学功能,本综述总结近年来该通道生物学功能及其与疾病的相关研究进展。  相似文献   
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