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61.
Maria Fernanda Nince Ferreira Verônica Moraes Oliveira Priscila Vieira da Cunha Osmindo Rodrigues Pires Júnior 《Toxicon》2010,55(7):1255-1262
This study evaluated the effects of [D-Leu1]Microcystin-LR variants, by the exposure of Hypophthalmichthys molitrix to Microcystis aeruginosa NPLJ4. Fish was placed in aquariums and exposed to 105 cells mL−1. For 15 days, 05 individuals were removed every 05 days, and tissue samples of liver, skeletal muscle and intestinal tract were collected for histopathologic analyses. Following exposure, those surviving were placed in clean water for 15 days to evaluate their recovery. A control without toxins was maintained in the same conditions and exhibited normal histology and no tissue damage. In exposed fish, samples were characterized by serious damages that similarly affected the different organs, such as dissociation of cells, necrosis and haemorrhage. Samples showed signs of recovery but severe damages were still observed. The results should be valuable to analyze the potency of microcystin toxicity and to help in the diagnosis of fish deaths. 相似文献
62.
Eduardo Kazuo Sannomiya Jun-ichi Asaumi Kanji Kishi Gisele da Silva Dalben 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(2):e41-e44
Dens invaginatus is a developmental variation resulting from an alteration in the normal growth pattern of the dental papilla. Synonyms of this disturbance include dens in dente, invaginated odontome, tooth inclusion, and dentoid in dente. Radiographically, it is observed as infolding of a radiopaque ribbon-like structure, with equal density as enamel, extending from the cingulum into the root canal and sometimes reaching the root apex, assigning the appearance of a small tooth within the coronal pulp cavity. This article presents 2 case reports. The first describes an 8-year-old girl with dens invaginatus in a mesiodens; the second report describes a 16-year-old boy presenting with 2 mesiodens, both associated with dens invaginatus. 相似文献
63.
P. A. da Silva M. M. S. Boffo I. G. de Mattos A. B. S. Silva J. C. Palomino A. Martin H. E. Takiff 《Clinical microbiology and infection》2006,12(3):293-296
Rapid, accurate and inexpensive methods are essential to detect drug-resistant Mycobacterium tuberculosis and allow timely application of effective treatment and precautions to prevent transmission. The proportion method, the MTT and Alamar Blue redox methods, and the D29 mycobacteriophage assay, were compared for their ability to detect resistance to isoniazid and rifampicin. When tested against a panel of known M. tuberculosis strains, the redox methods and the D29 assay showed good sensitivity and specificity compared to the proportion method, suggesting that they could be useful alternatives for identifying multidrug resistance in M. tuberculosis. 相似文献
64.
Edmo Atique Gabriel Rafael Fagionato Locali Carla Cristina Romano Alberto José da Silva Duarte José Honório Palma Enio Buffolo 《European journal of cardio-thoracic surgery》2007,31(3):406-412
OBJECTIVE: The objective of this study is to evaluate the inflammatory response caused by endovascular stents in the treatment of aortic aneurysms. METHODS: Twenty-five patients underwent endovascular stent treatment from March through December 2005. The evolution of mediators (sedimentation velocity, C reactive protein, interleukin-6, interleukin-8, tumor necrosis factor-alpha, intercellular adhesion molecule-1, l-selectin), inflammatory cells (leukocytes, lymphocytes, platelets), serum creatinine and body temperature within preoperative period and in the following postoperative periods--1, 6, 24 and 48 h, 7 days, 1-3 months, was analyzed. In order to achieve statistic significance, Friedman test and Wilcoxon test were used, with index of significance of 5% (p<0.05). RESULTS: Peak values of sedimentation velocity, C reactive protein and interleukin-6 were observed at 7 days (p<0.0001), 48 h (p<0.0001) and 24h (p<0.0001), respectively. Tumor necrosis factor-alpha and interleukin-8 did not show statistically significant variability during the entire follow-up. In terms of intercellular adhesion molecule-1 and l-selectin, their expressive values were found in late phase of follow-up, although without statistical significance. Elevation of leukocytes count occurred in premature phase of follow-up (p<0.0001), while lymphocyte and platelet count occurred in a late phase of follow-up (p<0.0001). Serum levels of creatinine did not show significant variability during follow-up. The period between 24 and 48 h corresponded to major frequency for fever (p<0.0001). CONCLUSION: Individual mediators analysis and inflammatory cells demonstrated variability of their values during postoperative follow-up. This could help in the analysis of the inflammatory response evolution caused by endovascular stent treatment for aortic aneurysms in premature and late phases after implantation of the vascular prosthesis. 相似文献
65.
女性控尿解剖学机制的MRI研究 总被引:1,自引:1,他引:0
目的探讨女性控尿的解剖学机制在MRI(磁共振成像)的表现和观察方法。方法对20例正常控尿的成年女性进行MRI扫描,采用八通道体部线圈、快束自旋回波(FSE)扫描序列进行扫描,采集静息时盆腔横断面、矢状面和冠状面影像。结果MRI显示,女性的尿道分三层结构,与病理学对照,由内向外依次为黏膜及黏膜下组织、肌肉、外膜组织,但无法区分平滑肌与括约肌;与控尿有关的盆底肌肉也能够清楚显示。结论MRI能够清楚观察到女性控尿的有关解剖结构,是观察女性控尿解剖结构的较理想影像方法。 相似文献
66.
Paulo Gustavo Sampaio Lacativa Laura Maria Carvalho de Mendon?a Pedro José de Mattos Patrício Filho José Raimundo Pimentel Manoel Domingos da Cruz Gon?alves Maria Lucia Fleiuss de Farias 《Journal of clinical densitometry》2005,8(3):352-361
Hyperparathyroidism contributes significantly to decreased bone mineral density (BMD) in end-stage renal disease patients, but this negative influence is not homogeneous throughout the skeleton. We studied the BMD by dual-energy X-ray absorptiometry on total body and on different regions of the skeleton in 42 patients with severe hyperparathyroidism on hemodialysis. We also evaluated the relationship between different risk factors and BMD found on the regions examined in these patients. The legs and other sites where cortical bone predominate were mostly affected, whereas trabecular bone was relatively preserved. This is probably the result of the different effects of hyperparathyroidism on cortical and trabecular bone, but we cannot rule out the interference of ectopic calcifications and sclerotic lesions of vertebral end-plates falsely increasing lumbar spine BMD. The main determinants of low total-body BMD were, in order of importance, immobility, high intact parathyroid hormone levels, low body mass index, and low albumin. Eleven patients presented with pathologic fractures, mainly in the legs, and BMD was lower in this group than in patients without fractures. In conclusion, our study makes clear that hyperparathyroidism is a great threat to bone density in hemodialysis patients, mainly in the legs, the site mostly affected by fragility fractures in our patients. Physicians must worry not only with high parathyroid hormone levels, but also with the nutritional state of these patients. 相似文献
67.
Gardenia C. G. Militão Daniel P. Bezerra Claudia Pessoa Manoel Odorico de Moraes Flavio A. F. da Ponte Mary Anne S. Lima Edilberto R. Silveira Letícia V. Costa-Lotufo 《Journal of natural medicines》2007,61(2):196-199
The purpose of this study was to investigate the antiproliferative activity of 2,3,9-trimethoxypterocarpan, a known pterocarpan
with cytotoxic activity against many tumor cell lines, in a panel of four leukemia cell lines (HL-60, Molt-4, Jurkat, and
K562) and on human peripheral blood mononuclear cells (PBMC). The pterocarpan showed IC50 ranging from 0.1 to 0.5 μg/ml at leukemic cells after 72 h of incubation, with K562 being the most resistant cell line. This
compound seemed to be selective to tumor cell lines, since at a concentration of 10 μg/ml after 72 h, it only reduced 19%
of viable peripheral mononuclear cells. 相似文献
68.
69.
Endocarditis secondary to Hemophilus parainfluenzae is an uncommon entity that appears to be increasing in frequency, perhaps due to improved laboratory isolation techniques. Although controversial, most of the published literature recommends a penicillin, with or without concomitant gentamicin, as definitive therapy. We report the first successful use of the third-generation cephalosporin ceftizoxime in an ampicillin-allergic patient. A 55-year-old white female was hospitalized after 5 days of experiencing fever, chills, nausea, and vomiting. A cardiac echocardiogram revealed a large mitral valve vegetation, and the patient was treated with intravenous ampicillin, gentamicin, and clindamycin. Two weeks after emergency mitral valve replacement the patient developed spiking fevers and a macular, erythematous rash while receiving ampicillin. Ceftizoxime was initiated and continued to complete a 4-week period of intravenous antibiotics. Follow-up at 14 months showed no further evidence of infection. Ceftizoxime appears efficacious in eradicating H. parainfluenzae in patients allergic to penicillin. 相似文献
70.
The effect of desmopressin on nocturnal polyuria, overnight weight loss, and morning postural hypotension in patients with autonomic failure 总被引:4,自引:0,他引:4
C J Mathias P Fosbraey D F da Costa A Thornley R Bannister 《British medical journal (Clinical research ed.)》1986,293(6543):353-354
Day and night urine volume, morning and evening body weight, and supine and sitting blood pressure were measured in five patients with chronic autonomic failure who were not receiving treatment with drugs. All had nocturnal polyuria, overnight weight loss, and a pronounced postural fall in blood pressure, with lowest levels in the morning. Desmopressin (2-4 micrograms given intramuscularly at 8 pm) reduced nocturnal polyuria, diminished overnight weight loss, raised supine blood pressure, and reduced the postural fall, especially in the morning, when patients were often at their worst. Desmopressin may be a useful alternative to, or may supplement, other forms of treatment in some patients with autonomic failure. 相似文献