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101.
The presented adsorption--process KOMBISORBON is applied for high efficient off-gas purification, preferably of polychlorinated dioxins and furans from off-gas of incineration plants, which are generated, when these are operated under unfavourable conditions [2]. This off-gas purification process complies with german laws, which limit the concentration of these substances to less than 0.1 ng toxicity equivalents (TE) per cubic metre of gas [1]. The adsorbent, the adsorption process and its plant concept (fixed bed) is described in detail including economics and obtained operation results. Alternative removal technologies are briefly outlined. 相似文献
102.
H Grunze RW Greene HJ M?ller T Meyer J Walden 《Canadian Metallurgical Quarterly》1998,791(1-2):330-334
Actions of the new antiepileptic drug lamotrigine were characterised using whole cell patch clamp recordings from rat CA1 pyramidal cells in vitro. The results suggest that lamotrigine, besides its previously described effect on the fast sodium inward current and calcium currents, modulates the transient potassium outward current ID. This may be an effective mechanism to inhibit pathological excitation. 相似文献
103.
The goal of work was to investigate the electrogenic transport of Na ions by Na+,K(+)-ATPase in membrane fragments absorbed on a planar bilayer lipid membrane. The photorelease of ATP from an inactive precursor, caged ATP, induced a transient current and changes in the net system capacitance measured during the application of an alternating voltage. The increments of capacitance (delta c) decreased with the increase in the frequency of the applied voltage. The characteristic frequency F0 of the steepest slope of the curve significantly decreased in solutions with high ionic strength (either NaCl or choline chloride), in which Na+ transport is decelerated. The value of delta c correlated with the total charge delta q transported across the membrane. The capacitance increments decreased when the Na+ concentration in solution decreased. At a concentration below 2 mM the increment became negative. The increase in membrane capacitance can be attributed to the charge relaxation process inside the protein, as discovered in the cells by other methods. The characteristic frequency F0 depends on the time constants of charge redistribution. The nonlinear dependences of delta c on delta q were explained by a voltage bias across the membrane fragments resulting from pumping. The potentials corresponding to the maximum capacitance change were similar to the midpoint potentials of the equilibrium charge distribution and depended on the Na+ concentrations in solution. The model enabled also the determination of the total capacitance of the active region of a lipid membrane with the adsorbed protein containing membrane fragments. 相似文献
104.
STUDY DESIGN: Retrospective analysis of 31 cases of cervical spondylotic myelopathy treated by four-level subaxial cervical corpectomy. OBJECTIVE: To determine whether extremes of anterior decompression and fusion have inordinate or unique levels of morbidity. SUMMARY OF BACKGROUND DATA: There is a paucity of data on experience with four-level corpectomy. However, counsel against such surgery can be found. MATERIALS AND METHODS: The records and studies of 31 consecutive cases of cervical spondylotic myelopathy, treated by four-level corpectomy, were retrospectively analyzed. Patients in 26 cases were observed longer than 2 years. No hardware was used in the procedures. External orthosis, worn for 6 months, was a Philadelphia-type collar in 25 patients and a halo vest in 6. RESULTS: Three patients died within 3 weeks of surgery (9.7%). Delayed radiculopathy occurred in four patients after surgery, three had acute graft complications, and one had pseudomeningocele, for a morbidity rate of 25.8%. There was no infection or worsened myelopathy. CONCLUSIONS: No unique morbidity is associated with extremes of subaxial decompression when compared with surgery of lesser extent. 相似文献
105.
HJ Cho JK Kim HC Park JK Kim DS Kim SO Ha HS Hong 《Canadian Metallurgical Quarterly》1998,154(1):224-230
In the present study, we evaluated changes in brain-derived neurotrophic factor (BDNF) immunoreactivity in the rat lumbar (L) 5 dorsal root ganglion (DRG) and areas where afferents from the DRG terminate, the L5 spinal cord and gracile nuclei, following unilateral sciatic nerve transection or crush. From 3 days to 4 weeks following cut or crush injury, the percentage of medium and large BDNF-immunoreactive neurons in the ipsilateral DRG increased significantly compared with those on the contralateral side. Following cut injury, there was no significant change in the percentage of small BDNF-immunoreactive neurons in the ipsilateral DRG; however, the intensity of immunoreactivity of these cells decreased. Following crush injury, however, both the percentage and intensity of small BDNF-immunoreactive neurons in the ipsilateral DRG significantly increased. Following cut injury, the expression of BDNF-immunoreactive axonal fibers decreased markedly in the ipsilateral superficial laminae of the L5 spinal cord and increased significantly in the ipsilateral deeper laminae of the spinal cord and gracile nuclei. Crush injury induced a marked increase in the expression of BDNF-immunoreactive axonal fibers in the superficial laminae of the spinal cord and gracile nuclei. These differences in BDNF response in the DRG and spinal cord after cut or crush injuries may reflect differences in trophic support to the injured DRG neurons and altered neuronal activity in the spinal cord and gracile nuclei following different types of peripheral nerve injury. 相似文献
106.
Benign solitary fibrous tumour, a rare mesenchymal tumour of adults, usually arises from the pleura. Only a few cases have been reported in the retroperitoneum and, to our knowledge, there has been no report of its imaging features. We describe the MRI features of benign solitary fibrous tumour arising from the pre-sacral space. 相似文献
107.
We investigated the contact guidance phenomenon of rat dermal fibroblasts (RDF) on microgrooved polystyrene substrates. Grooves were 1 microm deep, and between 1 and 10 microm wide. Light microscopy and digital image analysis (DIA) showed that RDF were oriented on all microgrooved substrates. Scanning electron microscopy showed that RDF cultured on 1 or 2 microm wide grooves were positioned on top of the ridges. On the wider 5 and 10 microm grooves, the cells were able to descend into the grooves. In confocal laser scanning microscopy, focal adhesions were lying in the same direction as the actin filament where they attached to. DIA confirmed an orientational behavior of focal adhesions and actin filaments on microgrooves. There were no differences in the measured orientation between the different grooves. Besides, no obvious preference was found for focal adhesions to lie along edges of the surface ridges. Transmission electron microscopy showed that focal adhesions were able to bend along the edges of ridges. On the basis of our observations, we suggest that the breakdown and formation of fibrous cellular components, especially in the filopodium, is influenced by the microgrooves. The microgrooves create a pattern of mechanical stress, which influences cell spreading and cause the cell to be aligned with surface microgrooves. 相似文献
108.
109.
BACKGROUND: Gastroesophageal reflux has been implicated in otolaryngologic problems, particularly chronic hoarseness that cannot be attributed to other causes. PATIENTS AND METHODS: To study this relationship between gastroesophageal reflux and chronic hoarseness we used 24-h dual-site ambulatory pH-recordings in 68 patients with chronic hoarseness and laryngeal lesions suggestive of acid irritation. RESULTS: Thirty-eight patients (56%) had evidence of at least one esophago-pharyngeal reflux episode. The mean number of esophago-pharyngeal episodes was 6.7 +/- 12 within 24 hours (range: 1-34 episodes). The mean duration of these episodes was 201 +/- 28 seconds (range: 6 seconds-19.6 minutes). Most patients with esophago-pharyngeal reflux had no evidence of pathologic gastroesophageal reflux. Only 28.9% of the patients with esophago-pharyngeal reflux episodes also had pathologic gastroesophageal phageal reflux, whereas 23.3% of the patients without esophago-pharyngeal reflux had no gastroesophageal reflux disease. The esophago-pharyngeal reflux occurred mainly in the upright position. CONCLUSIONS: Occult esophago-pharyngeal reflux, predominantly in the upright position, appears to be common and severe in patients with chronic hoarseness. Gastroesophageal reflux may be an important factor in the pathogenesis of chronic hoarseness. The causative mechanisms are not clear. 相似文献
110.
The overall rate of complications after ileal pouch-anal anastomosis is 60%. This rate, however, includes complications such as bowel-obstruction and hernias. Pouch-related complications occur after ileal pouch-anal anastomosis with a frequency of 15-25%. In an analysis of the recent literature the main risk factors are: tension of the ileal pouch-anal anastomosis, anastomotic leakage, lack of protective ileostomy, preoperatively undiagnosed Crohn's disease and the experience of the surgeon. We classified pouch related-complications into (1) surgical complications (leakage, bleeding, pelvic sepsis, fistulas); (2) technical problems (long S-pouch spout, rectal cuff stenosis, etc.); (3) functional problems (anal sphincter insufficiency, night incontinence, hypermotility, evacuation disorders); (4) pouchitis; (5) pouch neoplasias. Pathogenesis, diagnostic features, and medical and surgical therapy are discussed in detail. In our own series of 11 pouch-redo operations we had 6 pouch fistulas (3 related to Crohn's disease, 3 postoperative fistulas), 3 wrongly constructed pouches, 1 chronic pouchitis and 1 long S-pouch spout. In 3 cases the pouch had to be excised completely. Two patients remained with a permanent ileostomy. In 6 patients the pouch could be preserved on long term. Due to the technical complexity, the need to understand pathophysiology and the need for a differentiated diagnostic procedure, this operation should be performed only in specialised centers. 相似文献