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排序方式: 共有90条查询结果,搜索用时 15 毫秒
1.
本研究旨在探讨牦牛不同部位皮肤内血管和神经的分布情况,及检测低氧诱导因子-1α(HIF-1α)在不同部位皮肤上的定位及相对表达量,探究牦牛皮肤对高原低氧环境的适应机制。采用HE、Masson’s三色和Verhoeff VG染色法,对成年牦牛皮肤内血管和神经结构进行观察与分析;采用免疫组织化学、实时荧光定量PCR和蛋白免疫印迹法,对HIF-1α的mRNA和蛋白在成年牦牛皮肤组织中表达与分布进行研究。结果表明,颈部血管与神经密度最高,前臂部和小腿部次之,跖部最低,部位间差异显著(P<0.05)。HIF-1α主要表达在表皮层、毛囊的上皮根鞘、皮脂腺、汗腺、血管、神经;颈部、前臂部和小腿部强阳性表达,跖部阳性表达。HIF-1α mRNA的相对表达量跖部明显低于其他部位(P<0.05),其他三个部位两两比较差异不显著(P>0.05)。HIF-1α蛋白相对表达量颈部最高,跖部最低,差异显著(P<0.05)。研究结果提示,成年牦牛不同部位皮肤内不同血管和神经形态结构相似,密度从颈部到前肢再到后肢差异显著。HIF-1α的差异性表达进一步说明皮肤在牦牛适应低氧环境中发挥作用。  相似文献   
2.
ObjectiveTo describe an ultrasound-guided approach to the dorsal aspect of the quadratus lumborum muscle (D-QL) and to evaluate the spread of methylene blue dye in canine cadavers.Study designProspective, experimental anatomical study.AnimalsA total of 12 canine cadavers.MethodsThe ultrasonographic landmarks and injection technique for the D-QL approach were determined in two cadavers. Correct needle tip position was confirmed by computed tomography. Bilateral ultrasound-guided injections were performed in 10 cadavers between the QL muscle, the vertebral body and the ventrocaudal aspect of the transverse process of the first lumbar vertebra (L1) using two volumes of methylene blue: low volume (LV) 0.3 mL kg–1 or high volume (HV) 0.5 mL kg–1. Staining of the main thoracolumbar trunk, dorsal and ventral branches of the thoracic (T) and lumbar (L) spinal nerves, sympathetic trunk and epidural space were assessed following dissection. Data between groups were compared using Mann–Whitney U test. Data are presented as median (range).ResultsThe ventral branches of spinal nerves T12, T13, L1, L2, L3 and L4 were stained in 10%, 70%, 100%, 90%, 60%, 0% and 30%, 100%, 100%, 100%, 50% and 30% after LV and HV injections, respectively. Multisegmental spread of the sympathetic trunk was found on 3 (3–4) and 5 (3–6) vertebral spinal levels following LV and HV injections, respectively (p = 0.005). The T13 segment of the sympathetic trunk was stained after all HV injections. Epidural spread was found in 20% and 30% of LV and HV injections, respectively.Conclusions and clinical relevanceThe injection of HV versus LV dye using the D-QL approach provided more consistent staining of the thoracolumbar nerve structures which innervate the abdominal wall and viscera. Clinical studies are required to evaluate the analgesic efficacy of the D-QL block for abdominal procedures in dogs in vivo.  相似文献   
3.
用乙醛酸诱发灾光技术研究了14-30周胎儿眼结膜的肾上腺素能神经纤维的分布。发现角膜巩缘的肾上腺素能神经纤维主要与角巩膜的血管伴行,纤维数量随胎龄增加而增加,角膜基质层于16周以后有少量纤维,角膜内皮层和上皮层未发现神经纤维。  相似文献   
4.
鸡胆囊的交感传入神经元定位研究   总被引:3,自引:0,他引:3  
选用体重1.5~2.5kg的成年母鸡6只,将CT—HRP溶液注入胆囊壁,动物存活3~4d后,经左心室灌流固定,取胸、腰和荐段各脊神经节,制成50gm的连续冰冻切片,TMB法呈色反应,置明视野显微镜下观片统计。结果发现:支配鸡胆囊的交感传入神经元胞体位于T2~T7脊神经节,其峰值位于T6脊神经节。  相似文献   
5.
The muscular architecture and the distribution of nerves with vasoactive intestinal polypeptide-like (VIP-like) immunoreactivity were examined in the gastroduodenal junction of the chicken. Both the outer and the inner muscle layers (tunica muscularis) and the muscularis mucosae were examined. The inner muscle layer was divided into two parts, namely its inner and outer parts. The outer muscle layer was not present in the pyloric part but was found in the proventriculus and the duodenum. The muscle strands of the outer muscle layer ran longitudinally but were absent at the isthmus and the pylorus. Most of the outer part of the inner muscle layer was located in or close to the pyloric part. The muscle strands in the outer part connected the pyloric part with other regions, namely the craniodorsal muscle, the tendinous centres and the isthmus. The inner part of the inner muscle layer was widely distributed in the stomach. In the pyloric part, the muscle strands of this layer followed a circular or spiral course. The muscularis mucosae was not present in the caudodorsal and cranioventral muscles of the gizzard. In addition, VIP-like immunoreactive nerve fibres were predominantly distributed in the inner part of inner muscle layer of the pyloric part. These results suggest that the ventriculopyloric orifice and the pyloric part itself constrict with a sphincter-like action.Abbreviations VIP vasoactive intestinal polypeptide  相似文献   
6.
90年代以来凸显的新保守主义思潮与唐浩明历史小说之间具有一种内在的精神互动。其具体表现是作家对曾国藩、张之洞、杨度等被传统认知所定格的否定性历史人事,在历史维度上实行“同情”性评判,在价值层面上追求“同理”性思考。当然,因与传统文化过于同构而缺乏更加主动的超越,也使作家创作在取得突破性成就的同时,出现了忽视思想者历史作用和宽容暴力专制压迫这样两个值得注意的问题。  相似文献   
7.
8.
GAO Qun  NING Xin-jie  WANG Hui 《园艺学报》2018,34(8):1527-1531
The survival, proliferation and differentiation of Schwann cells are the decisive factors of peripheral nerve regeneration. Autophagy is an important mechanism to regulate homeostasis and make Schwann cells pass the stress period, thus providing protection for the survival of Schwann cells and becoming a key factor on nerve regeneration. Recent studies indicate that a number of microRNAs participate in the activity of Schwann cells and play an important regulatory role in the process of nerve injury repair. In our studies, we found that microRNAs played an important regulatory role in autophagy at the early stage of nerve injury. Therefore, the relationship between microRNAs and autophagy in Schwann cells during the regeneration and repair of peripheral nerve injury is described in this paper.  相似文献   
9.
AIM: To evaluate the guiding effect of high-frequency stimulation (HFS) on renal denervation (RDN), and to compare the similarities and differences of blood pressure changes at the time of electrical stimulation and radiofrequency ablation. METHODS: A total of 6 Kunming dogs were included in this study. Renal artery abnormalities were excluded by angiography. High-frequency stimulation and radiofrequency ablation were performed at the same sites from distal to proximal segments of the renal artery. Invasive blood pressure (BP) was recorded during the whole procedure. The change of the blood pressure was analyzed. HE and Masson staining was adopted to detect the structural changes in the wall of the renal artery and surrounding tissues. The immumohistochemical staining for tyrosine hydroxylase (TH) was used to observe the renal nerve damage after ablation. RESULTS: Electrical stimulation and radiofrequency ablation were delivered in a total of 50 sites. The BP increasing response was induced at 34% sites (n=17), while the rest sites (66%, n=33) had no response. Compared with the baseline, HFS caused the increases in systolic BP of (0.34±3.38), (0.41±3.04), (10.47±5.73), (13.27±3.63), (10.17±1.87) and (0.78±1.87) mmHg in 6 serial 20 s time segments during 120 s of HFS at positive BP response sites. Similarly, the increases in systolic BP by (-0.88±3.44), (-1.64±3.47), (13.17±3.12), (12.82±3.21), (9.50±2.68) and (-6.09±2.21) mmHg were observed during 120 s of ablation procedure at the same sites in 6 serial 20 s time segments. At non-responding sites, HFS and ablation failed to cause a significant increase in systolic BP. The mean area of nerves in the response sites was (0.51±0.28) mm2, whereas that in non-response sites was (0.09±0.06) mm2 (P<0.01). The average absorbance values of TH in renal nerves at ablation and non-ablation sites were 0.031±0.015 and 0.085±0.018 (P<0.01), respectively. CONCLUSION: Renal sympathetic nerves can be effectively mapped by HFS. Radiofrequency ablation guided by HFS is valid to injure sympathetic nerves around renal artery.  相似文献   
10.
为了研究交感神经对小鼠妊娠早期(妊娠第1~9天)子宫内膜发育的影响,本试验采用交感神经阻断剂6-羟多巴胺(6-OHDA,100 mg·kg~(-1)体质量)腹腔注射成年雌性昆明小白鼠,损毁外周交感神经.利用放射免疫分析法、组织学和免疫组织化学技术,检测了小鼠妊娠早期血清17β-雌二醇水平、子宫腺发育和子宫内膜细胞增殖的变化.结果显示:(1)在妊娠第1天(E1)、E5和E7 6-OHDA处理组血清中17β-雌二醇的含量分别降低了63.4%(P<0.01)、35.7%(P<0.05)和25.5%(P<0.05),而在E3和E9分别升高了79.3%(P<0.05)和156.7%(P<0.01);(2)6-OHDA处理降低了妊娠早期子宫腺的比例,与同期对照组相比分别下降了37.5%、38.6%、41.8%、61.4%和58.1%(P<0.01);(3)6-OHDA处理降低了妊娠早期子宫内膜细胞的增殖,使E1、E3、E5、E7和E9子宫内膜增殖细胞分别减少了27.2%、30.2%、40.7%、27.2%和27.7%(P<0.01).上述结果表明,交感神经对雌激素的分泌以及妊娠早期子宫组织结构的重建具有重要的调控作用,进而调节动物早期胚胎的着床和发育.  相似文献   
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