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81.
Hans-Peter Schlake Karl-Heinz Grotemeyer Ingolf Böttger Ingo Wilhelm Husstedt Günter Brune 《Neurosurgical review》1987,10(3):191-196
Migraine is considered to be a functional neurological disorder. In classical migraine (headache associated with prodromal visual field disturbances) and migraine accompagnée (headache associated with transient neurological symptoms), disturbances of cerebral blood flow and amine metabolism are thought to be pathogenetic factors. However, conventional methods of neuroimaging (CAT, NMR) usually do not yield any pathological findings in patients. Since 123I-iodoamphetamine (123I-IMP) crosses the intact blood brain barrier, 123I-IMP-SPECT is used for the assessment of cerebral perfusion in various neurological diseases, including functional disorders. 123I-IMP-SPECT was performed on 5 patients with classical migraine and 18 patients with migraine accompagnée. At the time of investigation, all patients were symptom-free. Cerebral blood flow was decreased in all patients with migraine accompagnée, and often corresponded to the site of headache as well as to the topography of transient neurological symptoms. This reduction was most obvious in a patient with persisting neurological symptoms. Most patients with classical migraine, however, did not show any alteration of cerebral perfusion. It appears that migraine--and in particular migraine accompagnée--is characterized by a permanent alteration not only of cerebral blood flow but also of neuronal activity. Migraine attacks may occur in connection with exacerbations of preexisting metabolic alterations. 相似文献
82.
Characterisation of surface-modified solid lipid nanoparticles (SLN): influence of lecithin and nonionic emulsifier. 总被引:1,自引:0,他引:1
M A Schubert C C Müller-Goymann 《European journal of pharmaceutics and biopharmaceutics》2005,61(1-2):77-86
Solid lipid nanoparticles (SLN), an alternative colloidal drug delivery system to polymer nanoparticles, emulsions and liposomes, are generally produced by high pressure melt-emulsification. However, the harsh production process is not applicable for formulations containing shear and temperature sensitive compounds. For that reason, subsequent adsorptive SLN loading might be a promising alternative. The aim of the present study was the development and characterisation of surface-modified SLN for adsorptive protein loading by variation of both the lipid matrix and the emulsifier concentration in the continuous phase. Variations in SLN composition resulted in particle sizes between 674 and 61 nm corresponding to specific surfaces of 4.5 m(2)/g and 48.9 m(2)/g and zeta potentials between -23.4 mV and -0.9 mV. In dependence of SLN surface properties, albumin payload ranged from 2.5 to 15%. Thermoanalysis, X-ray diffraction and electron microscopy revealed anisometrical and crystalline particles. In vitro cytotoxicity was low in terms of both haemolysis, which was between 1 and 2%, and neutral red test (NRT) showing a half lethal dose between 1.1 and 4.6%. 相似文献
83.
Results of total and subtotal colon resections in children. 总被引:2,自引:0,他引:2
AIM: The treatment of long-segment neuronal intestinal malformations confronts the paediatric surgeon with the problems of diagnosis, suitable surgical methods and postoperative care. The evidence based only on ganglion cells is inadequate to decide about the required extent of resection and does not exclude hypoganglionosis and disseminated dysganglionosis. For the surgical treatment, pouch procedures as well as the usual resection techniques according to Rehbein, Soave, and Duhamel are discussed. Since studies with greater numbers of patients are rare, we present here our own results. METHODS: 48 patients with long segment intestinal malformations were treated in our hospital between 1990 and 2000. A total of 35 patients were examined 1.5-6 years after definitive surgical therapy. Rehbein's anterior resection was performed in all cases. RESULTS: Our findings showed that the surgical treatment with Rehbein's technique offers good results, both with respect to complications as well as to the postoperative course, although a 4 cm long aganglionic segment remains in situ. We found that results were better after ascendorectostomy (n = 22) compared to ileorectostomy (n = 11). Earlier publications of this group (13) show that the histology of the proximal resection margin is decisive for the prognosis. Hypo- and aganglionic segments should be completely resected while short IND segments of the colon or terminal ileum may remain in situ. However, the additional effect of the aganglionic segment of the distal rectum and the decreased peristaltic flow of the pre-anastomotic bowel has to be taken into account. Further investigations are required to find out whether a combination of Soave's endorectal pull-through with a remaining neuronal dysplastic segment proximal to the resection margin may give better results or if the frequency of postoperative enterocolitis and incontinence increased in cases of long segment intestinal neuronal malformations. Accurate diagnosis of myenteric plexus is decisive for an optimal treatment and therefore, considering our results, it is essential that in case of newborns getting to hospital with colon obstruction and suspicion of neuronal intestinal malformation full thickness biopsies from the distal and proximal colon may be taken simultaneously with the enterostomy. Generally ileostomy is performed in patients suspected of long-segment neuronal intestinal malformations. Mucosa suction biopsies from the distal and proximal stoma side are less informative compared to full thickness biopsies. 相似文献
84.
85.
Studies of the blood lipid peroxide status and vitamin E levels in patients with chronic active hepatitis and alcoholic liver disease 总被引:1,自引:0,他引:1
M Mézes A Pár P Németh T Jávor 《International journal of clinical pharmacology research》1986,6(4):333-338
As free radicals and lipid peroxidation are involved in the pathogenesis of different inflammatory diseases of the liver, the blood malondialdehyde content, the activity or quantity of free radical eliminating enzymes and the natural antioxidant, vitamin E serum level has been studied in ten patients with chronic active hepatitis and in six subjects with alcoholic liver disease. Thirty healthy volunteers served as controls. The serum malondialdehyde/thiobarbituric acid reactive substance and its concentrations increased significantly in both hepatitis groups. The superoxide dismutase content was also raised in the patients' sera. The serum glutathione peroxidase (GSH-Px) activity was decreased in both groups, while the red blood cell GSH-Px showed a significantly lower activity in the alcoholic hepatitis patients. Serum catalase activity and vitamin E levels in both types of chronic hepatitis were not significantly different from the healthy controls. 相似文献
86.
87.
88.
89.
Selda Sarikaya Bektas Acikg?z Ismail Hakki Tekk?k Y Yücel Güngen 《Journal of clinical neuroscience》2007,14(9):901-904
We report a 24-year-old woman with an intramedullary conus ependymoma associated with holocord syringohydromyelia and syringobulbia. The tumor was removed and surgery for decompression of the syringohydromyelia was not considered at the first operation. In the follow-up examinations, MRI showed significant and steady improvement of syringohydromyelia. Symptoms associated with syringohydromyelia also disappeared. The cause of syringohydromyelia accompanying intradural spinal cord tumors appears to be either direct blockade of the central canal or secondary interruption of the central canal flow by compression of the perimedullary cerebrospinal fluid flow. As removal of the mass often corrects both these likely causes of the syringohydromyelia, no additional treatment for the drainage of the hydromyelia cavity syrinx is usually necessary. 相似文献
90.
F J von Baumgarten G Burkhard D Englert P Kraus H G Mertens G Müller-Berghaus H Przuntek 《European neurology》1987,27(3):149-154
Fibrinopeptide A (FPA), platelet-secreted protein, platelet factor 4 and beta-thromboglobulin were determined in the cerebrospinal fluid of patients who had suffered from subarachnoid hemorrhage and were treated with 6 g tranexamic acid or 4 million KIU aprotinin to prevent rebleeding. Platelet-secreted proteins and FPA were cleared from the cerebrospinal fluid within 3 days after bleeding. Their vasoactive and thrombotic capability is limited to the initiation period of vasospasm that usually comes to clinical observation 3-8 days after bleeding. Increased thrombotic activity of the cerebrospinal fluid, as reflected by high levels of FPA and platelet-secreted protein, seemed to promote the occurrence of neurological deficits. 相似文献