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201.
Axonotmesis of the left sciatic nerve was performed on adult male Wistar rats. T1 values of the crushed nerve samples were determined with proton magnetic resonance spectroscopy. Denervation changes of the dependent hind plantar flexor muscles were assessed with proton magnetic resonance imaging of their cross-sectional area and muscle force measurements. However, Tl relaxation time of the crushed nerve samples remained prolonged implying the absence of nerve regeneration. This would be in contradiction with what is known about regeneration after simple crash and the muscle force and magnetic resonance imaging measurements of the dependent plantar flexor muscles. These studies indicated that sufficient nerve regeneration had taken place to restore their muscle force and volume. A model is suggested to explain the persistence of prolonged Tl values in the presence of muscle force recovery. 相似文献
202.
M. Milčinski E. Henze R. Lietzenmayer M. Clausen R. Weller V. Hombach W. E. Adam M. Porenta 《European journal of nuclear medicine and molecular imaging》1991,18(1):17-22
The quantification of myocardial perfusion abnormalities is necessary to allow comparison of repeated studies, especially in the evaluation of the success of medical, interventional or combined treatment in stable coronary artery disease or in evolving myocardial infarction. The purpose of this study was to assess inter-observer reproducibility of tomographic study processing using a semi-automatic quantitative programme. Technetium 99m hexakis-2-methoxyisobutylisonitrile (99mTc-Sestamibi) was chosen for tomographic imaging of repeated rest-stress studies in patients with stable coronary artery disease. The quantification was performed using a modification of the Cedars polar coding and comparison with the normal data base. The perfusion defects were quantified separately for each standard perfusion area [left anterior descending (LAD), right coronary (RCA) and left circumflex (LCX) arteries] and total area of hypoperfused myocardium. The inter-observer variability for 40 tomographic studies was accomplished. The defects were the largest in the LAD perfusion area (average 19.7% of the normalized LAD supply area) with an inter-observer correlation of 0.84 for this region. The greatest variability was found for the LCX region (r=0.55) and is attributed to a small average perfusion defect (7.1%), only 18 studies having abnormal perfusion in this area. In total, an average 14.3% of the left ventricular myocardium was significantly hypoperfused, and the inter-observer correlation was 0.87. These results show good inter-observer reproducibility using semi-automatic quantitation of perfusion defects. Careful interpretation of smaller defects in the evaluation of treatment results is advised when repeated 99mTc-Sestamibi single photon emission tomography studies are processed by more than one observer.The work was performed at Nuclear Medicine Department in Ulm.
Offprint requests to: M. Milinski 相似文献
203.
Two newborn infants with duodenal and jejunal atresia and agenesis of the dorsal mesentery represent our surgical experience with "apple peel" small bowel or "christmas tree" demormity. The first patient had the typical appearance of this condition. The postoperative course was complicated by hyperbilirubinemia, septicemia, and disseminated intravascular coagulation. The infant is in satisfactory condition 1.5 years after operation. The second patient had agenesis of the dorsal mesentery without spiraling of the bowel around its vascular stalk. The child died after 1 month, with complete absence of extrahepatic bile ducts as seen at a second laparotomy. Neither child had been subjected to gastrostomy. 相似文献
204.
Atropine and scopolamine, injected intraventricularly, abolished typical emotional behaviour with aggression and autonomic and motor phenomena, as well as with clonic-tonic convulsions of intraventricularly injected muscarine. On the other hand, adrenergic and dopaminergic blocking agents, antihistamines, 5-hydroxytryptamine antagonists, antiepileptic drugs, and 5-hydroxytryptamine, administered intraventricularly, failed to antagonize the gross behavioural effects of intraventricular muscarine. However, ganglionic and sometimes neuromuscular blocking agents, as well as catecholamines and histamine injected intraventricularly, antagonized the emotional behaviour with aggression and depressed the autonomic and motor phenomena of small doses of intraventricular muscarine. In addition, emotional behaviour with aggression and autonomic and motor phenomena evoked by high doses of intraventricular muscarine were resistant to these antagonists administered intraventricularly. From these experiments it is concluded that the sites activated by muscarine in the CNS producing aggressive behaviour have the following characteristics: in high doses muscarine acted on muscarinic cholinoceptive sites, while in small doses it activated the cholinoceptive sites having muscarinic and nicotinic characteristics. Finally, the ability of single intraventricular injections of muscarine to trigger and to maintain the long-lasting gross behavioural effects cannot be ascribed to a rapid detonator transmission, but rather to an action that differs from a conventional transmitter function. 相似文献
205.
B. B. Mršulja B. J. Mršulja M. Spatz U. Ito J. T. Walker Jr. I. Klatzo 《Acta neuropathologica》1976,36(1):1-8
Summary Behaviour of biogenic amines was studied in the brains of Mongolian gerbils subjected to unilateral occlusion of the common carotid artery. Assays on the hemispheres ipsilateral to occlusion revealed in symptom-positive animals a progressive decrease in norepinephrine and dopamine, and an increase in serotonin throughout the duration of an ischemic insult. In post-ischemic periods following the release of the clip, changes in biogenic amine levels generally conformed to the principles of a previously described maturation phenomenon, with delayed reactions occurring after the shorter ischemic insults. 相似文献
206.
Dr. L. Stárka CSc Dr. R. Hampl CSc Dr. M. Bičíková Dr. J. Obenberger CSc 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1976,199(3):261-266
Summary The occurrence of testosterone, estrone, and estradiol-17 in aqueous humor and vitreous body of the rabbit eye was demonstrated. The identity of the steroid hormones was confirmed by their chromatographic properties, microreactions, and radiochemically by crystallization to constant specific activity of their labeled acetates. The levels of testosterone and estrogens in rabbit male and female plasma, aqueous, and vitreous were determined by radioimmunologic assay. The concentrations of the steroid hormones in plasma are higher than in aqueous and vitreous. However, testosterone in aqueous circulates in free form and lacks the binding to sexual hormone-binding globulin as in plasma.
Zusammenfassung Bericht über das Vorkommen von Testosteron, Oestron und Oestradiol-17 im Kammerwasser und Glasörper des Kaninchenauges. Die Art der Steroide wurde mittels Chromatographie, Mikroreaktionen und radiochemisch ermittelt. Der Testosteron- und Oestrogenspiegel im männlichen und weiblichen Kaninchenplasma, im Kammerwasser und Glaskörper wurde radioimmunologisch bestimmt. Die Plasmakonzentration der Steroidhormone lag höher als diejenige im Kammerwasser oder Glaskörper. Testosteron zirkuliert jedoch im Kammerwasser in freier Form, im Plasma dagegen ist es überwiegend an Sexualhormonebindende Globuline gebunden.相似文献
207.
Th1 dominance in HAM/TSP and the optico-spinal form of multiple sclerosis versus Th2 dominance in mite antigen-specific IgE myelitis 总被引:6,自引:0,他引:6
Horiuchi I Kawano Y Yamasaki K Minohara M Furue M Taniwaki T Miyazaki T Kira Ji 《Journal of the neurological sciences》2000,172(1):17-24
To clarify the Th1/Th2 balance in spinal cord inflammation, we used ELISA to measure the total and allergen-specific IgE in 69 patients with clinically definite multiple sclerosis (MS), including 24 patients with the optico-spinal form of MS, 45 with HAM/TSP, 30 HTLV-I carriers without HAM/TSP, 40 patients with acute myelitis, 43 with neurodegenerative disorders, and 42 healthy subjects, and flow cytometry to study the intracellular IFNgamma-positive versus IL-4-positive cell ratio (intracellular IFNgamma/IL-4 ratio) in peripheral blood CD4(+) T cells in 40 patients with MS, including 17 patients with the optico-spinal form of MS, 23 with HAM/TSP, 22 with acute myelitis, 23 with neurodegenerative disorders, and 36 healthy subjects. Patients with HAM/TSP showed a significantly higher intracellular IFNgamma/IL-4 ratio, lower IL-4(+)/IFN-gamma(-) cell percentages, lower total IgE level, and lower frequency of cedar pollen-specific IgE than did the controls. The patients with optico-spinal MS showed a significantly higher intracellular IFNgamma/IL-4 ratio and higher IL-4(-)/IFN-gamma(+) cell percentages than the controls even at remission or in the convalescence phase. In contrast, in the patients with acute myelitis, the total serum IgE level and the frequency of mite antigen-specific IgE were significantly elevated in comparison to the controls, while those having mite antigen-specific IgE myelitis showed a significantly lower IFNgamma/IL-4 ratio in the CD4(+) T cells in comparison to the controls. These findings suggest that the Th1 cell response is predominant in HAM/TSP and optico-spinal MS, whereas the Th2 cell response is predominant in mite antigen-specific IgE myelitis. 相似文献
208.
The most common pattern in subacute sclerosing panencephalitis, is in the cerebral hemisphere white matter on T2-weighted
images with or without atrophy. Brain-stem lesions are rare. We report brain-stem involvement in two children with subacute
sclerosing panencephalitis. A peculiar pattern, with involvement of the pons with extension to both middle cerebellar peduncles
and substantia nigra but sparing the pontine tegmentum, is suggested.
Received: 10 January 2000/Accepted: 18 April 2000 相似文献
209.
Brozzetti S Meli C Polistena A Musto F De Toma G Cavallaro A 《Il Giornale di chirurgia》2000,21(3):95-98
Multiple carcinoid tumors of the small bowel with more than 3 lesions are very unusual. The authors report a case with 4 lesions, 2 of those localized in the jejunum with more advanced infiltration of the wall and extension to regional mesenteric lymph nodes, revealed by ultrasonography. The relative low incidence and particularly the vague, nonspecific clinical presentation, the unusual site in the jejunum, and failure of the radiological examine of one year before lead to not suspect this condition prior to US examination. However, the feature of asymmetric, concentric thickening of the bowel wall requiring a more accurate exam by CT with oral contrast was able to confirm the suspect of the intestinal tumor. The patient, 80 year old, underwent radical surgery with a wide lymph nodes dissection as well as double resection of the jejunum and distal ileum. The post-surgical outcome was uneventful. A 12-month follow-up is free of the disease. 相似文献
210.
目的 在上海骨关节疾病患者中筛选吲哚美辛引起不良反应的危险因素。方法 利用回顾性流行病学调查方法 ,调查服用吲哚美辛的骨关节疾病患者的一般情况、原发疾病、疾病家族史、服用非甾体抗炎药前生活质量评估、饮食习惯、生活方式、非甾体抗炎药服用情况和不良反应发生情况等 ,通过单因素和多因素分析从中筛选吲哚美辛不良反应发生的相关因素。结果 上海骨关节疾病患者中口服吲哚美辛的不良反应发生率为 48 1%。因子“合并药物治疗”(比值比 0 166,95%可信区间 0 0 3 7~ 0 74)、“饮酒史”(比值比 0 795,95%可信区间 0 675~ 0 93 7)、“来自于健康问题的何种程度的紧张或压力会影响你的生活” (比值比0 917,95%可信区间 0 848~ 0 992 )评分的降低分别使口服吲哚美辛不良反应发生的危险增高。而因子“与 6mon前比较 ,服用非甾体抗炎药前的健康状况如何” (比值比1 2 3 6,95%可信区间 1 0 2 2~ 1 496)评分的升高将使口服吲哚美辛不良反应发生的危险增高。结论 “合并药物治疗”、“饮酒史”、“与 6mon前比较 ,服用非甾体抗炎药前的健康状况如何”是吲哚美辛不良反应发生的危险因子 相似文献