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排序方式: 共有998条查询结果,搜索用时 15 毫秒
41.
Ligia Aranibar Duran Jonathan Stevens González Carlos Palma Ducommun Solange Zapata Manque Javiera Pizarro Olave 《Piel》2017,32(10):604-609
Introduction
Tinea capitis (TC) is a dermatophytosis that affects the hair and scalp. The epidemiology of TC depends on the different geographical areas and is variable over time. Direct microscopic examination and fungal culture are essential to confirm the diagnostic suspicion and to identify the germ involved.Objectives
To determine the frequency of TC, to identify the etiological agents and to analyze the epidemiological aspects, in patients with suspected TC from Santiago Norte during the period 2009-2015.Materials and methods
A total of 505 patients with suspected TC were evaluated in the Dermatology Laboratory, Hospital Clinico Universidad de Chile. Direct microscopic examination was performed with KOH 30% and fungal culture of scalp lesions. Identification of the fungi was mainly morpho-physiological.Results
The diagnosis of TC was confirmed in 155 cases (30.7%). Male gender predominated (57.4%). The average age was 5 years. 85.2% of the cases occurred in the preschool and school population. The most frequent isolated agent was Microsporum canis in 89.8%, followed by Trichophyton tonsurans in 7.1%. It was confirmed that 81.8% of the cases of Trichophyton tonsurans had foreign ancestry, mainly of Haiti and Peru.Conclusions
This study evidenced the occurrence of Trichophyton tonsurans as a cause of TC, which could be explained by the increase in the immigrant population and the anthropophilic characteristics of the dermatophyte. 相似文献42.
Beat Moeckli Pamela Sun Franois Lazeyras Philippe Morel Solange Moll Manuel Pascual Lo H. Bühler 《Transplant international》2019,32(5):459-469
The lack of suitable kidney donor organs has led to rising numbers of patients with end stage renal disease waiting for kidney transplantation. Despite decades of clinical experience and research, no evaluation process that can reliably predict the outcome of an organ has yet been established. This review is an overview of current methods and emerging techniques in the field of donor kidney evaluation prior to transplantation. Established techniques like histological evaluation, clinical scores, and machine perfusion systems offer relatively reliable predictions of delayed graft function but are unable to consistently predict graft survival. Emerging techniques including molecular biomarkers, new imaging technologies, and normothermic machine perfusion offer innovative approaches toward a more global evaluation of an organ with better outcome prediction and possibly even identification of targets for therapeutic interventions prior to transplantation. These techniques should be studied in randomized controlled trials to determine whether they can be safely used in routine clinical practice to ultimately reduce the discard rate and improve graft outcomes. 相似文献
43.
Solange B. Tatani M.D. Antonio Carlos C. Carvalho M.D. Adagmar Andriolo M.D. Rogério Rabelo M.D. Orlando Campos M.D. Valdir A. Moises M.D. 《Echocardiography (Mount Kisco, N.Y.)》2010,27(4):442-447
Background: Although the residual lesions after surgical correction of tetralogy of Fallot (TOF) can be evaluated by Doppler echocardiography (DE), the relation of DE parameters with the proBNP level, a potential biomarker of right ventricle overload, is not well known. The objective of this study was to evaluate the DE parameters and their relation to proBNP levels. Methods: proBNP plasma level and Doppler echocardiography parameters were obtained on the same day in 49 patients later after repair of TOF (mean age of 14.7 years, 51% female, mean PO time of 9.5 years). The DE parameters studied were the dimensions of the right atrium (RA) and ventricle (RV), RV diastolic and systolic function, and residual pulmonary lesions. The relation between them and proBNP levels were analyzed and the cutoff values of DE parameters for elevated proBNP determined. Results: proBNP was elevated in 53% and correlated with RV diastolic diameter (r = 0.41; P = 0.003), RA longitudinal (r = 0.52; P = 0.0001) and transversal (r = 0.47; P = 0.001) diameters, pressure half time of pulmonary regurgitation (PR) velocity (PHT) (r =?0.42; P = 0.005), and the PR index (r =?0.60; P < 0.001). By multivariate analysis, the PR index (r =?597; P = 0,001; CI: ?913.2 to ?280.8) and RA longitudinal (r = 7.74; P < 0,001; CI 4.18 to 11.31) were independent predictors of elevated proBNP. PHT lower than 64 msec (0.76) and PRi lower than 0.65 (0.81) had the best accuracy for elevated proBNP. Conclusion: proBNP may be increased in patients after surgical repair of TOF, correlated with the size of right cardiac chambers and the severity of PR. (Echocardiography 2010;27:442‐447) 相似文献
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46.
Orlandini G Guizzardi S Ferretti S Simonazzi M Bucci G Gatti R 《Urologia internationalis》2002,69(3):233-235
The morphological and functional basis of the excellent clinical outcome of ileal orthotopic neobladders are largely unknown. Only long-term follow-up studies will provide an adequate answer to this unsettled question. We have studied a patient who underwent this type of surgery over 27 years ago. Besides an important secretive adaptation we have found, at the ultrastructural level, that the monolayered epithelium does not show signs of true metaplasia and that changes had occurred in the intercellular junctions, namely that desmosomes are significantly increased. Although limited to a single case, these features, if confirmed by further observations, suggest a working hypothesis for the understanding of the definitive phenotypic adaptation of the ileal epithelium to the new aggressive environment. 相似文献
47.
Bohrer D do Nascimento PC Binotto R Becker E Pomblum S 《JPEN. Journal of parenteral and enteral nutrition》2002,26(6):382-388
BACKGROUND: The extent of aluminum contamination in parenteral nutrition solutions was measured in 35 different commercial products, including amino acids, electrolytes, glucose, lipids, vitamins trace elements, and albumin. The extent of aluminum contamination in substances used as raw material for preparation of parenterals was also measured. Chemicals from different manufacturers and of different quality grades were analyzed individually. METHODS: The measurements were done by atomic absorption spectrometry. RESULTS: The results showed that the same product might have different aluminum content depending on the manufacturer, either for commercial formulations or substances. The highest contaminated chemicals included cystine, NaOH, vitamin C, biotin, gluconate, and Fe and Cr salts. The lowest contaminated chemicals included lipids, apolar amino acids, glucose, HCI, acetic acid, KCl, NaCl, and heparin. Among commercial products, the major contamination rates appeared in calcium gluconate, followed by trace elements, some vitamins, bicarbonate, phosphates salts, and heparin. CONCLUSIONS: Comparing the aluminum in commercial products and substances, it can be concluded that the contamination may occur in parenterals because aluminum is present naturally in the chemicals. However, when the composition and concentration of the parenteral solution are considered, the contamination of calcium gluconate, trace elements, some vitamins, phosphates, bicarbonate, and heparin cannot be related only to the raw substances. The aluminum level present in these commercial formulations is too high to come only from the substances; therefore, it is possible that one of the steps of the manufacturing procedure is responsible for elevating the contamination of these products. 相似文献
48.
Mortara RA Andreoli WK Taniwaki NN Fernandes AB Silva CV Fernandes MC L'Abbate C Silva Sd 《Anais da Academia Brasileira de Ciências》2005,77(1):77-94
Trypanosoma cruzi, the etiological agent of Chagas disease, occurs as different strains or isolates that may be grouped in two major phylogenetic lineages: T. cruzi I, associated with the sylvatic cycle and T. cruzi II, linked to the human disease. In the mammalian host the parasite has to invade cells and many studies implicated the flagellated trypomastigotes in this process. Several parasite surface components and some of host cell receptors with which they interact have been identified. Our work focused on how amastigotes, usually found growing in the cytoplasm, can invade mammalian cells with infectivities comparable to that of trypomastigotes. We found differences in cellular responses induced by amastigotes and trypomastigotes regarding cytoskeletal components and actin-rich projections. Extracellularly generated amastigotes of T. cruzi I strains may display greater infectivity than metacyclic trypomastigotes towards cultured cell lines as well as target cells that have modified expression of different classes of cellular components. Cultured host cells harboring the bacterium Coxiella burnetii allowed us to gain new insights into the trafficking properties of the different infective forms of T. cruzi, disclosing unexpected requirements for the parasite to transit between the parasitophorous vacuole to its final destination in the host cell cytoplasm. 相似文献
49.
This article describes a percutaneous fixation technique for a midwaist scaphoid fracture using an antegrade (dorsal) guidewire and a retrograde (volar) cannulated screw placement. This simplified hybrid technique allows for accurate dorsal central wire placement and stable internal fixation with minimal violation of the articular cartilage of the proximal pole of the scaphoid. 相似文献
50.
Fantini SM Paiva JB Rino Neto J Dominguez GC Abrão J Vigoritto JW 《Brazilian Oral Research》2005,19(3):176-182
The present study assessed condylar displacement between initial maximal habitual intercuspation (MHI) and centric relation (CR), recorded after using a deprogramming occlusal splint for an average period of 7.8 +/- 2.1 months prior to any orthodontic treatment. The sample consisted of 22 subjects, 11 male and 11 female, with an average age of 14.2 +/- 1.4 years, with Class II malocclusion and with no apparent signs or symptoms of temporomandibular dysfunction (TMD). Condylar displacement was measured using a Panadent axis position indicator in decimal fractions of a millimeter. The original mean vertical displacements and the corresponding standard deviations were 4.24 +/- 2.53 mm and 3.86 +/- 2.72 mm, respectively, for the right and left sides. Because a significant negative correlation was observed between original condylar displacements and age factors, the displacement values were statistically adjusted to 2.74 +/- 2.00 mm and 2.44 +/- 1.93 mm. On the horizontal plane, the mean displacements measured were -0.72 +/- 1.53 mm on the right side and -0.51 +/- 1.98 mm on the left. The mean displacement on the transversal plane was 0.03 +/- 0.87 mm. A comparison between these values and those observed in non-deprogrammed groups, as well as those published in the related literature, indicates that use of occlusal splints results in greater mean condylar displacement values, especially vertically, between CR and MHI positions, which contributed to a more accurate orthodontic diagnosis. 相似文献