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51.
Renal and pulmonary Aspergillus granulomas in two 6-year-old boys with chronic granulomatous disease were treated by nephrectomy and lobectomy as well as intravenous amphotericin B and granulocyte transfusion. After lobectomy two smaller pulmonary aspergillomas resolved with medical therapy. The second child's condition improved after nephrectomy, but he died with disseminated Aspergillus infection. This experience suggests that surgical excision of localized Aspergillus granulomas in conjunction with specific antimicrobial therapy provides temporary clinical improvement and may prevent further blood-borne dissemination of the fungus.  相似文献   
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Summary The authors describe changes in the ultrastructure of degenerate tendon that has undergone spontaneous rupture.The cellular elements show alteration of shape and widespread fatty degeneration. The cytoplasmic organules (mitochondria, rough endoplasmic reticulum, Golgi apparatus) are often completely absent, proof of a reduced metabolic activity of the cells.The matrix also shows serious degenerative phenomena with irregular orientation of the collagen fibrils frequently with variation in diameter, fraying and absence of periodicity.
Résumé Les auteurs décrivent les modifications de la structure microscopique des tendons dégénérés qui ont été le siège d'une rupture spontanée.Les éléments cellulaires sont déformés et témoignent d'une dégénérescence graisseuse étendue. Les organes cytoplasmiques (mitochondries, réticulum endoplasmique granuleux, appareil de Golgi) ont souvent disparu, ce qui est la preuve d'une diminution de l'activité métabolique des cellules.Il existe également d'importants phénomènes dégénératifs au niveau de la matrice, avec orientation irrégulière des fibres de collagène, qui présentent des variations de diamètre, un aspect effiloché et une absence de périodicité.
  相似文献   
53.
OBJECTIVES: To describe our experience concerning sudden sensorineural hearing loss (SSNHL) in a large single-institution series of SSNHL patients and to discuss the results. METHOD: This was a retrospective study, and the charts of 156 consecutive inpatients (65 males, mean age 44 years, range 10-74 years; 91 females, mean age 46 years, range 15-75 years) with the diagnosis of SSNHL from 1987 to 2000 were reviewed. One hundred forty-three of 156 patients received multidrug therapy (plasma expanders, antiaggregants, steroids), whereas only 13 SSNHL patients received hyperbaric oxygen therapy. RESULTS: Old age, vascular and metabolic risk factors, and cigarette smoking do not a have a high prevalence in the SSNHL population. An etiologic factor was detected in 23 of 156 (15%) cases (16 cases of acute infection, 4 cases of neurovascular conflicts, 2 cases of cerebellar angiomas, 1 case of cochleovestibular schwannoma). The outcome was not related to the laterality, age, or hearing loss type. On the contrary, a statistically significant association between poor recovery and male sex, both tinnitus and vertigo, and the initial severity of the hearing loss was observed. CONCLUSIONS: Mostly, SSNHL results in idiopathic disease. At present, diagnostic and therapeutic efforts appear to be inadequate to improve the prognosis of SSNHL. Further studies are needed to obtain better knowledge about the etiopathogenesis of SSNHL so that new therapeutic strategies can be considered in the treatment of this challenging ear disease.  相似文献   
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The appearance of multidrug resistance (MDR) of tumour cells to a wide array of antitumour drugs, structurally diverse and having different mechanisms of action, constitutes the major obstacle to the successful treatment of cancer. Our approach to search for non-cross resistant antitumour agents is based on the rational design of derivatives, which have a high kinetics of passive cellular uptake rendering their active efflux by MDR exporting pumps inefficient. Recently, two families of acridine cytotoxic agents were obtained, pyrazoloacridines (PACs) and pyrazolopyrimidoacridines (PPACs). The aim of this study was to examine molecular basis of the reported differences in retaining cytotoxic activity of these derivatives at cellular level against resistant erythroleukaemia K562/DOX (overexpressing P-glycoprotein) cell line. The study was performed using a spectrofluorometric method, which allows continuous monitoring of the uptake and efflux of fluorescent molecules by living cells. It was demonstrated that the presence of two additional rings, pyrazole and pyrimidine, fused to the acridine chromophore structure (PPAC) favoured more rapid cellular diffusion than the presence of only one additional pyrazole ring (PAC). The presence of hydrophobic substituent OCH3 markedly favoured the cellular uptake of pyrazoloacridines and pyrazolopyrimidoacridines while compounds having hydrophilic substituent OH exhibited very low kinetics of cellular uptake. In contrast, it was found that neither structure of the ring system nor the hydrophobic/hydrophilic character of examined substituents determined the rate of active efflux of these compounds by P-glycoprotein. Our data showed that a nearly linear relation exists between the resistance factor (RF) and lnV+ reflecting the impact of the cellular uptake rate (V+) on the ability of these compounds to overcome MDR.  相似文献   
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57.
Recent interest in anthrax is due to its potential use in bioterrorism and as a biowarfare agent against civilian populations. The development of rapid and sensitive techniques to detect anthrax spores in suspicious specimens is the most important aim for public health. With a view to preventing exposure of laboratory workers to viable Bacillus anthracis spores, this study evaluated the suitability of PCR assays for detecting anthrax spores previously inactivated at 121 degrees C for 45 min. The results indicate that heat treatment ensures the complete inactivation of B. anthracis spores without significantly affecting the efficiency of PCR assays.  相似文献   
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59.
Seven patients affected by McCune-Albright syndrome with polyostotic fibrous dysplasia were operated on either for fracture fixation or for correction of bone deformity. Ten femurs, three tibiae, and one humerus were stabilized by intramedullary titanium nailing with a modified unreamed femoral nail (UFN) and standard unreamed tibial (UTN) and humeral (UHN) nails. The age of the patients at operation ranged from 8 to 30 years, with an average of 17 years, and the length of follow-up ranged from 8 months to 4 years, with an average of 2 years. Before operation, each patient had suffered from a minimum of three fractures to a maximum of 12, with an average of six fractures. The femur was the most affected skeletal segment. Before surgery, two patients were wheelchair-dependent owing to their severe lower limb bone deformities. At follow-up, all the patients were painless and all were able to walk even though one had to wear a bilateral long leg brace and another had to ambulate with the aid of two crutches. No patient had had additional fractures after surgery. The main intra-operative technical problems of this demanding surgical procedure were: a) reaming of a new medullary canal through the fibrodysplastic bone; b) the amount of blood loss in femoral surgery that ranged from 800 to 2,500 ml.  相似文献   
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