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961.
962.
The energy metabolism of the English E-CMO strain of contagious equine metritis bacterium was studied in whole cells and cell extracts. This bacterium appears to have an active Krebs cycle and probably obtains energy by oxidative phosphorylation since glycolysis and the hexose monophosphate pathways appear to be absent. These conclusions are based on the findings that [U-14C]glucose incorporation by this bacterium is below the level of detection, and that respiration is stimulated by Krebs cycle intermediates (i.e., malate, citrate, and succinate), but not by glucose, fructose, maltose, or sucrose. Furthermore, support comes from the fact that enzymes generally associated with the Krebs cycle and electron transport (i.e., malate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase, fumarate hydratase, malate dehydrogenase [decarboxylating], cytochrome oxidase, superoxide dismutase, NADH dehydrogenase, and catalase) were detected. Those enzymes normally associated with glycolysis and the hexose monophosphate pathways (i.e., hexokinase, glucose 6-phosphate dehydrogenase, fructose biphosphate aldolase, glycerol 3-phosphate dehydrogenase, phosphoenolpyruvate carboxykinase, pyruvate kinase, phosphate acetyl transferase, acetate kinase, alcohol dehydrogenase, and lactate dehydrogenase) were below the level of detection. 相似文献
963.
964.
In the present study, we performed immunohistochemical studies to investigate the changes of Bcl-2 and Bax in the central nervous system of the transgenic mice expressing a human Cu/Zn SOD mutation. In contrast to the controls, a high density of Bcl-2-IR astrocytes were detected all around the gray matter of the spinal cord of the mutant transgenic mice. Bcl-2-IR astrocytes were also detected in the cerebellum and brainstem of transgenic mice. Specific immunoreactivity for Bax was seen in the spinal cord and brainstem of transgenic mice. Immunostaining for Bax was identified only in neurons and not in glial cells. Our present study demonstrated the distribution of Bcl-2 and Bax in detail using immunohistochemical methods through the central nervous system of the transgenic mice, for the first time. 相似文献
965.
Previous in vitro studies using cell cultures or brain slices have demonstrated that phospholipase D (PLD) in the nervous system is involved in the signaling mechanism in response to a variety of agonists. However, little is known about the pathophysiological role of PLD-mediated signaling in the adult brain. We examined the changes in the expression of a PLD isozyme, PLD1, in the adult rat hippocampus, using immunological approaches and an assay for PLD activity after transient forebrain ischemia (four-vessel occlusion model) that results in the selective delayed death of CA1 pyramidal cells and induces reactive astrocytes in the CA1 subfield. In the control hippocampus, PLD1 the level of immunoreactivity was very low. After ischemia, in parallel with the results of Western blot analysis and the PLD activity assay, immunohistochemical analysis of PLD1 demonstrated that the immunoreactive proteins peaked at 7-14 days and were most prominent in the CA1 and the dentate hilar region. The temporal and spatial patterns of immunoreactivity of both PLD1 and glial fibrillary acidic protein (GFAP) were very similar, indicating that reactive astrocytes express PLD1, confirmed by double staining for PLD1 and GFAP. These results demonstrate that reactive astrocytes upregulate PLD in vivo after injury in the adult rat hippocampus. 相似文献
966.
Kim JH Shin JH Shim TS Hong SJ Ko GY Lim JO Song HY 《Journal of vascular and interventional radiology : JVIR》2004,15(9):1003-1008
Covered retrievable expandable nitinol stents were successfully placed in nine patients with tuberculous bronchial strictures refractory to balloon dilation. Complications included stent migration (n = 1) and tissue hyperplasia at the proximal portion of the stent (n = 2). During the follow-up period (5-52 months), stricture recurred in three of five patients (60%) after temporary stent placement for 2 months, whereas stricture did not recur in the other four patients after temporary stent placement for 6 months. Temporary placement of covered retrievable stents appears to be an effective method for the treatment of patients with tuberculous bronchial strictures refractory to balloon dilation. 相似文献
967.
Kil-Ho Cho Sung Moon Lee Young Hwan Lee Kyung Jin Suh Sung Moon Kim Myung Jin Shin Han Won Jang 《Korean journal of radiology》2004,5(4):280-286
Objective
We wished to report on the MRI findings of non-infectious ischiogluteal bursitis.Materials and Methods
The MRI findings of 17 confirmed cases of non-infectious ischiogluteal bursitis were analyzed: four out of the 17 cases were confirmed with surgery, and the remaining 13 cases were confirmed with MRI plus the clinical data.Results
The enlarged bursae were located deep to the gluteus muscles and postero-inferior to the ischial tuberosity. The superior ends of the bursal sacs abutted to the infero-medial aspect of the ischial tuberosity. The signal intensity within the enlarged bursa on T1-weighted image (WI) was hypo-intense in three cases (3/17, 17.6%), iso-intense in 10 cases (10/17, 58.9%), and hyper-intense in four cases (4/17, 23.5%) in comparison to that of surrounding muscles. The bursal sac appeared homogeneous in 13 patients (13/17, 76.5%) and heterogeneous in the remaining four patients (4/17, 23.5%) on T1-WI. On T2-WI, the bursa was hyper-intense in all cases (17/17, 100%); it was heterogeneous in 10 cases and homogeneous in seven cases. The heterogeneity was variable depending on the degree of the blood-fluid levels and the septae within the bursae. With contrast enhancement, the inner wall of the bursae was smooth (5/17 cases), and irregular (12/17 cases) because of the synovial proliferation and septation.Conclusion
Ischiogluteal bursitis can be diagnosed with MRI by its characteristic location and cystic appearance. 相似文献968.
Esophagorespiratory fistula: long-term results of palliative treatment with covered expandable metallic stents in 61 patients 总被引:18,自引:0,他引:18
PURPOSE: To evaluate long-term clinical results of palliative treatment of esophagorespiratory fistulas (ERFs) with covered expandable metallic stents. MATERIALS AND METHODS: Sixty patients with ERFs due to esophageal or bronchogenic carcinoma and one patient with ERF due to pressure necrosis caused by initial esophageal stent placement for esophageal carcinoma were treated with covered expandable esophageal or tracheobronchial metallic stents. Information about technical success of stent placement, initial clinical success and failure, fistula reopening, and complications was obtained. Survival curves for both patient groups with initial clinical success and failure were obtained and compared with Kaplan-Meier methods and log-rank test. RESULTS: Stent placement was technically successful in all patients, with no immediate procedural complications. The stent completely sealed off the fistula in 49 (80%) of 61 patients so that they had no further aspiration symptoms (initial clinical success). Twelve (20%) of 61 patients had persistent aspiration symptoms due to incomplete ERF closure (initial clinical failure). During follow-up, the fistula reopened in 17 (35%) of 49 patients with initial clinical success: In eight patients, the reopened ERF was sealed off successfully with stent placement or balloon dilation. In two patients with reopened ERF caused by food impaction, the reopened fistula resolved spontaneously. Seven patients did not undergo further treatment. All patients died during follow-up, and mean survival was 13.4 weeks (range, 1-56 weeks) after stent placement. Mean survival in patients with initial clinical success was significantly longer than that in patients with initial clinical failure (15.1 vs 6.2 weeks, P <.05). CONCLUSION: Covered expandable metallic stents were placed in 61 patients with ERFs, but the initial clinical success rate was poor and the rate of reopening was high; however, interventional treatment was effective for sealing off reopened ERFs. Copyright RSNA, 2004 相似文献
969.
Jin Kyu Kim Jun Jae Shin Sang Keun Park Yong Soon Hwang Tae Hong Kim Hyung Shik Shin 《Journal of Korean Neurosurgical Society》2013,54(4):296-301
Objective
We conducted a retrospective study examining the outcomes of intracerebral hemorrhage (ICH) in patients with chronic kidney disease (CKD) to identify parameters associated with prognosis.Methods
From January 2001 to June 2008, we treated 32 ICH patients (21 men, 11 women; mean age, 62 years) with CKD. We surveyed patients age, sex, underlying disease, neurological status using Glasgow Coma Scale (GCS), ICH volume, hematoma location, accompanying intraventricular hemorrhage, anti-platelet agents, initial and 3rd day systolic blood pressure (SBP), clinical outcome using the modified Rankin Scale (mRS) and complications. The severity of renal functions was categorized using a modified glomerular filtration rate (mGFR). Multifactorial effects were identified by regression analysis.Results
The mean GCS score on admission was 9.4±4.4 and the mean mRS was 4.3±1.8. The overall clinical outcomes showed a significant relationship on initial neurological status, hematoma volume, and mGFR. Also, the outcomes of patients with a severe renal dysfunction were significantly different from those with mild/moderate renal dysfunction (p<0.05). Particularly, initial hematoma volume and sBP on the 3rd day after ICH onset were related with mortality (p<0.05). However, the other factors showed no correlation with clinical outcome.Conclusion
Neurological outcome was based on initial neurological status, renal function and the volume of the hematoma. In addition, hematoma volume and uncontrolled blood pressure were significantly related to mortality. Hence, the severity of renal function, initial neurological status, hematoma volume, and uncontrolled blood pressure emerged as significant prognostic factors in ICH patients with CKD. 相似文献970.
Animals' rhythmic movements, such as locomotion, are considered to be controlled by neural circuits called central pattern generators (CPGs), which generate oscillatory signals. Motivated by this biological mechanism, studies have been conducted on the rhythmic movements controlled by CPG. As an autonomous learning framework for a CPG controller, we propose in this article a reinforcement learning method we call the "CPG-actor-critic" method. This method introduces a new architecture to the actor, and its training is roughly based on a stochastic policy gradient algorithm presented recently. We apply this method to an automatic acquisition problem of control for a biped robot. Computer simulations show that training of the CPG can be successfully performed by our method, thus allowing the biped robot to not only walk stably but also adapt to environmental changes. 相似文献