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31.
JA Alaejos Fuentes T López-Alburquerque J De Portugal Alvarez 《Canadian Metallurgical Quarterly》1997,14(5):239-240
We report a 20-year-old man affected by glycogenosis type III with distal muscle weakness, more severe in distal leg muscles. The electromyogram showed myopathic features. Nerve conduction studies and central motor conduction after magnetic stimulation of the brain were normal. Our results suggest that there is no involvement of central motor pathways in this disease. 相似文献
32.
JA Carballido Rodríguez 《Canadian Metallurgical Quarterly》1997,21(7):641-643
A case of a large dentigerous cyst containing a canine tooth in the maxillary antrum is presented. This case is of interest due because of its extensiveness and the presence of a canine tooth in the roof of the maxillary sinus. In addition, this caused a right-sided epiphora. Enucleation of the cyst containing the ectopic tooth was made. 相似文献
33.
JA Burger A Ochs K Wirth DP Berger R Mertelsmann R Engelhardt M Roessle K Haag 《Canadian Metallurgical Quarterly》1997,8(2):200-202
BACKGROUND: The increase in portal vascular resistance is a significant complication of metastatic disease to the liver or locally advanced cancer, e.g., biliary cancer. PATIENTS AND METHODS: This paper describes the successful palliative treatment of two cancer patients with portal hypertension presenting with the symptoms of tense ascites, mesenteric congestion, and severe variceal bleeding. By creating a stenttract between a hepatic vein and a main branch of the portal vein and/or by placing an extendable stent into the portal vein, the transjugular intrahepatic portosystemic stent-shunt (TIPS) technique was used to decompress the portovascular system. RESULTS: The TIPS-technique offers a new, safe and effective palliation for malignant portal hypertension. In both patients, the symptoms of the portal hypertension disappeared after the procedure. This was accompanied by a significant improvement of the patients performance status allowing an early ambulation. CONCLUSION: Our findings demonstrate the feasibility and effectiveness of the TIPS procedure as a minimal invasive treatment for portal vein decompression in selected tumor patients. 相似文献
34.
M Fernández Arjona J Mu?oz-Delgado Salmerón S Shihadei PJ Colomar JA García Estevez 《Canadian Metallurgical Quarterly》1997,21(1):64-66
The application of frozen and radiation sterilized allogenic bone grafts for reconstructions in orthopaedic operations is described. Analysis of results of treatment of 1125 patients was performed. It was found that use of preserved bone allows to reduce the extend and duration of surgery. Nearly total substitution of grafts may be seen in 3 to 8 months after surgery. 相似文献
35.
SK Patterson JA Tworek MA Roubidoux MA Helvie HA Oberman 《Canadian Metallurgical Quarterly》1997,169(3):709-712
OBJECTIVE: The objective of this study was to describe the mammographic appearance with pathologic correlation of metaplastic carcinoma of the breast. CONCLUSION: Metaplastic carcinomas of the breast are masses with mammographic characteristics of low suspicion because of their histologic appearance. Metaplastic carcinoma should be included in the differential assessment of predominately circumscribed, noncalcified masses revealed on mammography. One salient feature that may distinguish metaplastic carcinomas is the occurrence of a circumscribed portion with a spiculated portion, which is seen in carcinomas that have a significant mixture of metaplastic and invasive carcinoma growth patterns. 相似文献
36.
The effect of chloroquine (CHQ) administration on antioxidant enzymes in rat liver and kidney was studied. Male Sprague-Dawley rats were administered 20 mg/kg CHQ once a week for 4 weeks (chronic treatment) or a single dose at 10 or 20 mg/kg (acute treatment). Antioxidant enzyme activities were determined in cytosolic fractions of liver and kidney, whereas reduced glutathione (GSH) and malondialdehyde (MDA) were determined in tissue samples. Results indicate minimal effects of acute CHQ treatment, whereas chronic treatment with CHQ differentially affected antioxidant enzymes in the two organs. Superoxide dismutase activity was increased nearly twofold, while activities of selenium glutathione peroxidase (GPX), catalase, and NAD (P) H: quinone oxidoreductase were decreased in livers of CHQ-treated rats compared to controls. No significant effects of CHQ on glutathione reductase, GSH, and MDA levels were seen in the liver. Fewer effects of CHQ were observed in the kidney where a decrease in GPX activity and an increase in MDA levels was seen. Lowering of antioxidant enzymes activities in the liver by CHQ could render the organ more susceptible to subsequent oxidative stress; while increased MDA production after CHQ treatment in the kidney indicate that the organ is being subjected to oxidative stress. This could have implications for prolonged chloroquine intake. 相似文献
37.
DR Gehlert DT Stephenson DA Schober K Rash JA Clemens 《Canadian Metallurgical Quarterly》1997,31(5):705-713
Peripheral benzodiazepine receptors (PBRs) are expressed in a variety of tissues but are normally found at low levels in the brain. Following various types of nerve injury, a reactive gliosis results that exhibits a high expression of this receptor. To further characterize the expression of PBRs following neuronal injury, we evaluated PBR expression in the facial nucleus following facial nerve axotomy (FNA). Injury to a peripheral nerve results in a complex series of metabolic and morphological changes around the injured neuron. Transections of the facial nerve results in a rapid activation of both astrocytes and microglia around axotomized motor neurons. FNA resulted in an increase in the staining for both astrocytes (glial fibrillary acidic protein) and activated microglia (OX42). There was also a reduction in synaptic contacts with the motor nucleus as evidenced by reduced staining for the synaptic marker, synaptophysin. In sections labeled with [3H]-PK11195, the subsequent autoradiograms displayed marked increases in the labeling for PBRs. This increase was observed at 5, 7 and 10 days after nerve transection. The increase was primarily in the level of expression (Bmax), with no change in the affinity of the ligand (Kd). The increase in PBR expression after FNA supports the hypothesis that PBRs can be used as a sensitive marker for CNS injury. 相似文献
38.
Bladder psoas hitch is an surgical technique which, in very complicated cases, like repeated failures of vesico-ureteral re-implants or undiversions, allow us to bridge the shortness of the ureter and obtain a good vesico-ureteral reimplant. The surgical maneuver is described and several of the 11 cases operated by this technique are commented. The results are presented. 相似文献
39.
JA Koutcher AA Alfieri RL Stolfi ML Devitt JR Colofiore LD Nord DS Martin 《Canadian Metallurgical Quarterly》1993,53(15):3518-3523
The combination of N-(phosphonacetyl)-L-aspartate, 6-methylmercaptopurine, and 6-aminonicotinamide has been shown to be an effective antineoplastic regimen and also to enhance the effects of other chemotherapeutic agents. The mechanism of action of this combination of drugs is not known definitively, but one possible mechanism is biochemical modulation of energy metabolism and inhibition of production of tumor ATP. Tumor-bearing mice were treated with N-(phosphonacetyl)-L-aspartate, followed 17 h later by 6-methylmercaptopurine and 6-aminonicotinamide. 31P nuclear magnetic resonance spectroscopic studies demonstrated a significant depletion of high energy phosphates at 10 h post-6-methylmercaptopurine and 6-aminonicotinamide. The addition of radiation at this time was shown to induce a significantly longer tumor growth delay and a greater number of regressions (including durable complete regressions) than either chemotherapy or radiation alone. The combination of chemotherapy and radiation was found to be supra-additive compared to the antineoplastic effects of either modality administered separately, without a measurable increase in host toxicity. 相似文献
40.
The binding thermodynamics of the HIV-1 protease inhibitor acetyl pepstatin and the substrate Val-Ser-Gln-Asn-Tyr-Pro-Ile-Val-Gln, corresponding to one of the cleavage sites in the gag, gag-pol polyproteins, have been measured by direct microcalorimetric analysis. The results indicate that the binding of the peptide substrate or peptide inhibitor is entropically driven; i.e., it is characterized by an unfavorable enthalpy and a favorable entropy change, in agreement with a structure-based thermodynamic analysis based upon an empirical parameterization of the energetics. Dissection of the binding enthalpy indicates that the intrinsic interactions are favorable and that the unfavorable enthalpy originates from the energy cost of rearranging the flap region in the protease molecule. In addition, the binding is coupled to a negative heat capacity change. The dominant binding force is the increase in solvent entropy that accompanies the burial of a significant hydrophobic surface. Comparison of the binding energetics obtained for the substrate with that obtained for synthetic nonpeptide inhibitors indicates that the major difference is in the magnitude of the conformational entropy change. In solution, the peptide substrate has a higher flexibility than the synthetic inhibitors and therefore suffers a higher conformational entropy loss upon binding. This higher entropy loss accounts for the lower binding affinity of the substrate. On the other hand, due to its higher flexibility, the peptide substrate is more amenable to adapt to backbone rearrangements or subtle conformational changes induced by mutations in the protease. The synthetic inhibitors are less flexible, and their capacity to adapt is more restricted. The expected result is a more pronounced effect of mutations on the binding affinity of the synthetic inhibitors. On the basis of the thermodynamic differences in the mode of binding of substrate and synthetic inhibitors, it appears that a key factor to understanding resistance is given by the relative balance of the different forces that contribute to the binding free energy and, in particular, the balance between conformational and solvation entropy. 相似文献