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991.
Although stress fractures are well recognized, their frequency, sequelae and complex aetiology are often under-rated. In this case report, we describe an unusual case of simultaneous bilateral stress fractures of the proximal tibial shaft in a young man, exposed to a sudden increase in unaccustomed joint loading due to his part-time occupation. The pathogenesis is discussed. 相似文献
992.
Borna disease (BD) is a virus-induced immunopathologic disease of the central nervous system in a variety of species from birds to primates and probably in humans. Severe inflammatory reactions lead to tissue destruction and finally to cortical brain atrophy. After experimental infection of the rat, intraparenchymal CD8+ T cells, MHC class I Ags on Borna disease virus (BDV)-infected neurons, and numerous nerve cell lesions were present. Treatment of BDV-infected rats with the mAb OX-8 directed against CD8+ cells inhibited the immunopathologic reactions and reduced MHC class I Ag expression. Neuronal lesions were minimal and no loss of brain substance could be observed. Because BDV has no acute cytopathic effects, we provide evidence that the presence of CD8+ T cells within the brain parenchyma and the expression of MHC class I Ags on neurons play a major role for immunopathologic brain tissue destruction and virus-infected neurons in vivo can be destroyed by T cell-mediated cytotoxicity. 相似文献
993.
CA Pototschnig I Schneider HE Eckel WF Thumfart 《Canadian Metallurgical Quarterly》1996,105(7):521-524
Botulinum toxin A was used preoperatively to temporarily paralyze the intrinsic laryngeal muscles to hinder movements during the healing period after operation. In addition, toxin was injected into the cricopharyngeal muscle to allow a better passive drainage of the saliva into the esophagus. We treated six patients. Three suffered from chronic aspiration problems after multiple lower cranial nerve lesions, and three patients were apallic (after stroke and major brain injury). Two weeks before scheduled operation, we injected the toxin into the posterior cricoarytenoid muscles, the aryepiglottic muscles, and the vocalis muscle on both sides, as well as the cricopharyngeal muscle. The amount of injected toxin varied between 1.0 and 1.4 mL, equal to 200 to 280 units of botulinum toxin A (Dysport). After a complete palsy of these muscles (controlled by direct electromyography), a closure of the larynx was performed. After laminotomy and exposure of the intralaryngeal structures, the false vocal cords were mobilized and adapted with sutures. Because involuntary movements of the intralaryngeal musculature were absent, primary healing without complications occurred in all cases. Aspiration and related complications disappeared in all patients. In addition, the intensity of patient care could be considerably reduced. Preoperative use of botulinum toxin A allows sufficient laryngeal closure. This procedure is especially useful in the treatment of children and young adults, preserving the ability of later speech rehabilitation because of the return of voluntary movements of the intrinsic laryngeal muscles 6 months after the injection. Furthermore, this technique, as minimal surgical intervention, can be performed in high-risk patients. 相似文献
994.
The behavioral effects of alpha-MSH, MCH, and alpha-MSH + MCH were investigated in the ventromedial nucleus (VMN) and medial preoptic area (MPOA) (bilateral, 100 ng in 0.5 microliter). Infusion of alpha-MSH into the VMN increased aggressive behavior; in the MPOA it reduced exploration and increased anxiety. In both areas it stimulated sexual behavior. MCH also stimulated sexual behavior in the MPOA and VMN and had an anxiogenic effect in the MPOA. The effect of alpha-MSH on aggression and exploration was antagonized by MCH. When given together, the two peptides were mutually antagonistic on anxiety. This study indicates that MCH has central nervous system effects and may be a partial alpha-MSH agonist. 相似文献
995.
996.
997.
Significant advances in this past decade have improved our understanding of erectile physiology. A variety of tests are available for diagnosing impotence. SRE testing provides objective physiological information that is useful for indexing erectile capability and formulating a rational treatment plan. As such, SRE testing is a powerful noninvasive tool for assessing dysfunction. Nonetheless, in making a final diagnosis, the skillful clinician relies on more than one assessment parameter and on clinical acumen. 相似文献
998.
Capillary electrophoresis has been presented as a resourceful technique for monitoring the purity of synthetic metallophthalocyanines and evaluating comparatively purification procedures. In this study, the tetrasulfonated cobalt(II) phthalocyanine was synthesized by the condensation method and submitted to several purification procedures such as continuous Soxhlet extraction with ethanol and dioxane, percolation through a gel-filled chromatographic column, and salting-out precipitation in acid medium followed by washing with alkaline solution. The efficiency of each procedure, or combined procedures, was then evaluated by capillary electrophoresis in citrate buffer solution under constant voltage conditions and direct UV-VIS detection at 630 nm and 260 nm. The inorganic anion and cation composition of the purified fractions was also investigated by indirect UV analysis in chromate/cetyltrimethylammonium bromide (CTAB) and imidazole/hydroxyisobutyric acid (HIBA) electrolyte systems, at 254 nm and 214 nm, respectively. The electropherograms obtained at 630 nm showed a high-intensity peak surrounded by satellite peaks of small intensity with migration time of approximately 5-6 min. This profile is indicative of the formation of positional isomers under the synthesis conditions. The electropherograms obtained at 260 nm were useful to monitor contaminants, such as reaction by-products or unreacted starting materials. The salting-out precipitation of the crude product led to a good-quality product with 80% purity (elemental analysis based on nitrogen content), which is comparable to the purity of commercially available tetrasulfonated derivatives. Both UV and infrared (IR) spectra of the purified product resemble that of standards. The capillary electrophoresis ion analysis of the treated product revealed the presence of sodium carbonate as the major contaminant. The combined treatment of salting-out precipitation followed by percolation in a Sephadex column (Pharmacia, S?o Paulo, Brazil) was successful for the removal of carbonate ion. However, the percolation procedure seemed to cause minor demetallation of the macrocycle ring, as confirmed by the presence of free cobalt(II) in the electropherogram of the column eluted fraction. 相似文献
999.
Superficial angiomyxomas are rare, benign, dermal and subcutaneous tumours. We describe a 12-year-old girl who presented with a nodular swelling in the midline of her scalp that had been present since birth. Histological examination revealed an ill-defined myxoid lesion within the dermis, comprising spindle cells, blood vessels and occasional multi-nucleate giant cells. Immunohistochemical staining was negative for S-100, cytokeratin and smooth muscle actin, but focally positive for CD34. Our patient is unusual in that the angiomyxoma was present at birth, which has not previously been described. The importance of screening patients with cutaneous myxomas for cardiac lesions is discussed. 相似文献
1000.
PR Brakeman AA Lanahan R O'Brien K Roche CA Barnes RL Huganir PF Worley 《Canadian Metallurgical Quarterly》1997,386(6622):284-288