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31.
32.
Dexamethasone treatment attenuates early seawater instillation-induced acute lung injury in rabbits. 总被引:8,自引:0,他引:8
Ding Xinmin Duan Yunyou Peng Chaosheng Feng Huasong Zhou Pingkun Meng Jiguang Xue Zhiqian Xu Qinzhi 《Pharmacological research》2006,53(4):372-379
There is very little evidence on the value of giving corticoids in cases of seawater drowning induced acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Therefore, this study aimed to investigate whether dexamethasone treatment can attenuate seawater instillation-induced acute lung injury in rabbits. Seawater (4 ml/kg body weight) was instilled into the lower trachea of ventilated, anesthetized rabbits. Then these rabbits were assigned randomly 20 min later to receive intravenous injection of 1mg/kg body weight of dexamethasone (dissolving in 2 ml of normal saline) or 2 ml of normal saline. All animals demonstrated immediate drops in arterial oxygen tension (PaO2) and the total thoracic compliance, which were significantly improved after 2 h of dexamethasone treatment. Histopathological study also indicated that dexamethasone treatment markedly attenuated lung histopathological changes, alveolar hemorrhage and inflammatory cells infiltration with evidence of decreasing of myeloperoxidase (MPO) activity and tumor necrosis factor-alpha (TNF-alpha) concentration in lung tissue. In addition, dexamethasone treatment reduced extravascular lung water and lung epithelial-endothelial barrier permeability, up-regulated the expression of surfactant protein-A (SP-A) and alpha-epithelial Na+ channel, and increased Na+/K+-adenosine triphosphatase (Na+/K+-ATPase) activity and Na+/K+-ATPase-alpha1 protein abundance. Thus, these data indicate that dexamethasone treatment might be of benefit in patients with seawater aspiration-induced ALI. 相似文献
33.
34.
Manuel P Magalh?es 《Revista portuguesa de cardiologia》2003,22(10):1197-1199
35.
Abnormal spinal interactions from hand afferents to forearm muscles in writer's cramp. 总被引:1,自引:0,他引:1
G Louren?o J-P Bleton C Iglesias M Vidailhet V Marchand-Pauvert 《Clinical neurophysiology》2007,118(10):2215-2226
OBJECTIVE: Spinal reflexes from hand to wrist muscles were investigated in writer's cramp. METHODS: Stimulus-triggered rectified EMG averages after ulnar nerve and cutaneous stimulation, in wrist flexors and extensors during tonic contraction, were compared in 18 controls and 19 patients. RESULTS: On the patient dystonic side, ulnar-induced EMG suppression was decreased in wrist extensors, and facilitation in wrist flexors modified dependent on the dystonic wrist posture during writing. No change was found on the patient non-dystonic side. Cutaneous stimulation increased wrist flexor EMG on both sides of the patients with normal wrist posture during writing, but had no effect in controls and patients with abnormal wrist posture. CONCLUSIONS: Comparison between cutaneous and mixed nerve stimuli suggests that spindle afferents from intrinsic hand muscles may mediate patients' ulnar-induced EMG modulations. Abnormal proprioceptive control was only observed on dystonic side, while bilateral unusual cutaneous control was found in patients. Changes in spinal transmission were partly related to the dystonic wrist posture, suggesting that systems involved in sensory processing can be differentially altered in writer's cramp. SIGNIFICANCE: Changes in spinal transmission, probably related to peripheral and/or cortical inputs, might either take part in primary or adaptive mechanisms underlying writer's cramp. 相似文献
36.
Nelson G Ordó?ez 《Modern pathology》2006,19(1):34-48
The histologic distinction between peritoneal epithelioid mesotheliomas and serous carcinomas diffusely involving the peritoneum may be difficult, but it can be facilitated by the use of immunohistochemistry and electron microscopy. D2-40 and podoplanin are two recently recognized lymphatic endothelial markers that can be expressed in normal mesothelial cells and mesotheliomas. The purpose of this study is to compare the value of these new mesothelial markers with those that are commonly used for discriminating between mesotheliomas and serous carcinomas, and also to determine the current role of electron microscopy in distinguishing between these malignancies. A total of 40 peritoneal epithelioid mesotheliomas and 45 serous carcinomas of the ovary (15 primary, 30 metastatic to the peritoneum) were investigated for the expression of the following markers: D2-40, podoplanin, calretinin, keratin 5/6, thrombomodulin, MOC-31, Ber-EP4, B72.3 (TAG-72), BG-8 (Lewis(Y)), CA19-9, and leu-M1 (CD15). All 40 (100%) of the mesotheliomas reacted for calretinin, 93% for D2-40, 93% for podoplanin, 93% for keratin 5/6, 73% for thrombomodulin, 13% for Ber-EP4, 5% for MOC-31, 3% for BG-8, and none for B72.3, CA19-9, or leu-M1. All 45 (100%) serous carcinomas were positive for Ber-EP4, 98% for MOC-31, 73% for B72.3, 73% for BG-8, 67% for CA19-9, 58% for leu-M1, 31% for keratin 5/6, 31% for calretinin, 13% for D2-40, 13% for podoplanin, and 4% for thrombomodulin. After analyzing the results, it is concluded that Ber-EP4 and MOC-31 are the best negative mesothelioma markers for differentiating between epithelioid mesotheliomas and serous carcinomas. The best discriminators among the positive markers for mesotheliomas are D2-40, podoplanin, and calretinin. From a practical point of view, Ber-EP4 and MOC-31, in combination with calretinin, and/or D2-40 or podoplanin allow the differential diagnosis to be established between mesothelioma and serous carcinoma in nearly all instances. As a clear distinction could be made between these two malignancies in all of the cases in which electron microscopy was performed, this technique can be very useful in establishing the correct diagnosis when the immunohistochemical results are equivocal or further support of a diagnosis of either mesothelioma or serous carcinoma is needed. 相似文献
37.
E Chankiewitz D Peschke L Herberg I Bazwinsky E Mühlbauer H-J Br?mme E Peschke 《Experimental and clinical endocrinology & diabetes》2006,114(5):262-269
The New Zealand obese mouse (NZO/Hl) is characterised by hereditary obesity and type-2 diabetes, including insulin resistance, hyperinsulinaemia, and glucose intolerance. In other diabetic models, it has been revealed that the proper functioning of the glucose transporter isoform 2 (GLUT2) is essential for adequate secretion of insulin. The aim of this study was to compare the distribution of islet cells and GLUT2, as well as the expression of GLUT2-mRNA, in the pancreas of NZO mice and metabolically unimpaired NMRI (Naval Medical Research Institute) mice. Pancreas tissue was obtained from different stages of development. For molecular determination of the expression level of GLUT2-mRNA, total-RNA was extracted from the pancreas and analysed by quantitative real-time RT-PCR. All investigated NZO mice displayed increased weight, elevated hyperinsulinaemia, and slightly enhanced blood glucose levels compared with the NMRI control mice. By means of immunofluorescence microscopy drastically reduced insulin levels were detected, which might be compensated by the observed islet cell hyperplasia and hypertrophy. Furthermore, the normally peripheral localisation of the alpha-cells within islets was disturbed. By contrast, there were no changes in somatostatin cell distribution. However, considerable differences appeared with regard to GLUT2: whereas the beta-cells of NMRI mice showed dense immunostaining of the GLUT2 transporter on the cell surface, in all age groups of NZO mice, GLUT2 on the plasma membranes was reduced and dispersed in the cytoplasm. These findings agree with the molecular biological results, which displayed decreased mRNA-expression of GLUT2. In summary, the observed alteration of islet morphology and of GLUT2 expression in diabetic mice complements our previous results from a superfusion protocol and further clarifies the mechanisms of diabetogenesis in NZO mice. 相似文献
38.
网络环境下医学专题检索服务的深化 总被引:3,自引:2,他引:1
分析网络环境下图书馆定题服务的现状和价值,提出跟踪服务的方式,进行分阶段的、具体的定题服务,并实例分析分阶段定题服务的优势。 相似文献
39.
对鲜山药中水溶性粗多糖的提取工艺进行了研究,通过单因素试验和L9(34)正交试验,研究了料液比、提取温度、时间和乙醇体积分数对粗多糖得率的影响,极差分析及方差分析结果表明提取温度和料液比是影响山药粗多糖提取的主要因素,较优的工艺为料液比1 g:9 mL,温度50 ℃,时间2.5 h,乙醇体积分数75%,在此工艺条件下,鲜山药粗多糖得率为0.2449%(以鲜山药质量计). 相似文献
40.
目的建立胰胆管合流异常的动物模型。方法选用健康杂种猫10只。术前禁食12 h,3.5%戊巴比妥钠麻醉后,取上腹正中切口约6 cm切开各层至腹腔。于胆总管入十二指肠处旁边,切开胰腺背膜,解剖胰管;靠近十二指肠处分别纵向切开胰管、胆管长约4~6 mm的切口。6-0线间断吻合切口,造成类似人类的胰胆管合流的共同通道。术后20天胆道造影。结果术后动物精神、食欲良好,无萎靡、烦燥等表现,造影显示胰胆管合流共同通道延长。结论本动物模型最接近于人类的胰胆管合流异常生理,优于其他动物模型。 相似文献