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991.
992.
CB Marinelli KJ Donly JS Wefel JR Jakobsen GE Denehy 《Canadian Metallurgical Quarterly》1997,31(6):418-422
PURPOSE: Chorioretinal toxoplasmosis can threaten visual function when located in the posterior pole. The aim of this study was to compare the advantages and disadvantage of combination of malocid-sulfadiazine and clindamycin subconjunctivally. METHODS: Two groups of patients affected by unilateral chorioretinal toxoplasmosis were studied. The diagnosis was performed in 77% of cases on acqueous humor analysis. The first group of twenty-six patients was treated with a combination of malocid-sulfadiazine while the second group (seventeen patients) was treated with clindamycin subconjunctivally. Local and general corticosteroids were associated in all cases. Mean follow-up was 19 months in the first group and 16.5 months in the second. RESULTS: Visual acuity was increased in 88.5% of cases in the first group and in 94% of cases in the second group. Cicatrization obtained in both groups was comparably delayed 1.68 months for the first and 1.26 months for the second. Recurrences were rarely observed in the two groups: respectively 8% and 6% of cases. No local and general complication was noted. CONCLUSION: These findings suggest the advantages of subconjunctival clindamycin treatment due to the absence of general hematological toxicity. 相似文献
993.
JS Tapanainen K Aittom?ki J Min T Vaskivuo IT Huhtaniemi 《Canadian Metallurgical Quarterly》1997,15(2):205-206
In implantable cardioverter-defibrillator therapy with endocardial lead systems, certain clinical variables are associated with defibrillation energy requirements. Because of the weak correlation coefficients, these variables cannot predict defibrillation thresholds in individual patients. 相似文献
994.
995.
C Zimmermann G Steiner K Skriner W Hassfeld P Petera JS Smolen 《Canadian Metallurgical Quarterly》1998,41(11):1938-1945
OBJECTIVE: The characteristics of 3 patients with longstanding rheumatoid arthritis (RA) and consecutive evolution of limited cutaneous systemic sclerosis (IcSSc) were evaluated and compared with those of patients with IcSSc alone (n = 20) or with RA alone (n = 120). METHODS: Clinical features of the different patient populations were compared. Serologic analyses included tests for antinuclear antibodies (ANA) and ANA subsets, in particular anticentromere antibodies (ACA) and anti-heterogeneous nuclear RNP (hnRNP)-A2/RA33 (anti-A2/RA33). RESULTS: The 3 patients with RA developed IcSSc 11, 29, or 50 years after the onset of RA. Features of IcSSc were Raynaud's phenomenon, sclerodactyly, and telangiactasias in all 3 patients, and esophageal dysmotility in 1 patient. Rheumatoid factor (RF) and anti-A2/ RA33 were each found in 2 patients, and 1 of these patients was seropositive for both RF and anti-A2/RA33. ACA titers were positive in all cases. However, similar to the development of RA prior to IcSSc, the occurrence of autoantibodies typical of RA preceded the occurrence of ACA, at least in 2 of the patients. Using affinity-purified antibodies, cross-reactivities between anti-centromere protein A (CENP-A) and anti-CENP-B antibodies with anti-A2/RA33 antigens were seen in the 2 anti-A2/RA33-positive patients. Such cross-reactivities were not found in IcSSc patients without concomitant RA. Epitope mapping revealed that both autoantibody specificities recognized the known major epitopes: anti-CENP-B reacted with the C-terminal region and anti-A2/RA33 with the second RNA binding domain in the N-terminal region of hnRNP-A2. CONCLUSION: The RA-lcSSc overlap syndrome in these 3 patients with longstanding RA was characterized by an incomplete CREST (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasias) syndrome. The study demonstrated the presence of autoantibodies typical of both diseases and cross-reactivity of ACA with hnRNP-A2/RA33 in the sera of these patients. 相似文献
996.
Particulate air pollution, including coal fly ash, contains iron, and some of the pathological effects after inhalation may be due to reactive oxygen species produced by iron-catalyzed reactions. The objective of this study was to determine whether iron, present in coal fly ash, was mobilized, leading to ferritin induction in human airway epithelial cells, and whether the size of the particles affected the amount of iron mobilized. Three types of coal were used to generate the three size fractions of fly ash collected. The Utah coal fly ash was generated from a bituminous b coal, the Illinois coal fly ash from a bituminous c coal, and the North Dakota coal fly ash from a lignite a coal. Three size fractions were studied to compare the amount of iron mobilized in human airway epithelial (A549) cells and by citrate in cell-free suspensions. The size fractions selected were fine (<2.5 microm) and coarse (2.5-10 microm) components of PM10, airborne particulate matter <10 microm in diameter, and the fraction greater than 10 microm. Coal fly ash samples were incubated with 1 mM citrate to determine if iron associated with coal fly ash could be mobilized. Iron was mobilized by citrate from all three size fractions of all three coal types to levels as high as 56.7 nmol of Fe/mg of coal fly ash after 24 h. With all three coal types, more iron was mobilized by citrate from the <2.5 microm fraction than from the >2.5 microm fractions. Further, the mobilized iron was in the Fe(III) form. To determine if iron associated with the coal fly ash could be mobilized by A549 cells, cells were treated with coal fly ash, and the amount of the iron storage protein ferritin was determined after 24 h. Ferritin levels were increased by as much as 11.9-fold in cells treated with coal fly ash. With two of the three types of coal studied, more ferritin was induced in cells treated with the <2.5 microm fraction than with the >2.5 microm fractions. Further, inhibition of the endocytosis of the coal fly ash by the cells resulted in ferritin levels that were near that of the untreated cells, suggesting that iron was mobilized intracellularly, not in the culture medium. The results of this study suggest that differences in particle size and speciation of iron may affect the release of iron in human airway epithelial cells. 相似文献
997.
998.
OBJECTIVE: To determine whether consistent tissue effects are obtained when laser lesions are produced with a commercially available diode laser that are near the limit of clinical detection at the time of treatment. METHODS: Continuous-wave or micropulse diode laser was used to produce clinically undetectable (subthreshold) or barely detectable (threshold) retinal lesions in pigmented rabbits. Tissue effects at intervals after treatment were determined in retinal pigment epithelial (RPE) whole mounts by fluorescence microscopy, and in sections of retina and RPE by light and electron microscopy. RESULTS: Continuous-wave and micropulse laser lesions that were originally clinically undetectable were detectable as zones of pigment mottling after 5 days. By microscopy, compaction and/or swelling was seen in the outer retina, and cells in the RPE monolayer became heterogeneous in size, shape, and pigmentation, but the tissue responses in the outer retina and RPE were variable even within and among lesions in the same eye. CONCLUSIONS: Subthreshold energies used to create both continuous-wave and micropulse laser lesions produced variable effects on the RPE and the overlying neurosensory retina. It appears that, near the minimum effective dose of laser irradiation, individual RPE cell heterogeneity becomes detectable as variability in sensitivity to laser injury. CLINICAL RELEVANCE: As laser energy is reduced to limit collateral tissue damage in clinical applications, it may be difficult to generate reproducible lesions because of heterogeneity among individual cells. 相似文献
999.
AE Morgan SP Porter FA Clarkson ND Volkow JS Fowler SL Dewey 《Canadian Metallurgical Quarterly》1997,26(4):423-427
Small cell carcinoma of the larynx is an uncommon epithelial tumor, which is the most aggressive subtype of neuroendocrine carcinomas. Because of its nonspecific clinical and radiological manifestations, the diagnosis of small cell carcinoma of the larynx is essentially based on the light microscopic examination aided by electron microscopy or immunohistochemical staining. We report a case of supraglottic small cell carcinoma accompanied by large bilateral cervical lymph node metastasis ocurring in a 70-year-old man. On CT scans, no area of low attenuation indicating necrosis was demonstrated within such large metastatic lymph nodes. We suggest that small cell carcinoma of the larynx should be included in the diagnostic considerations when a laryngeal mass is accompanied by large cervical lymph nodes without necrosis shown by CT. 相似文献
1000.