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131.
Jacobus H. Schuurmans Stekhoven Jr Inés Isabel Silva Pedro San Román 《Parasitology research》1957,17(6):490-509
Ohne ZusammenfassungMit 2 Textabbildungen 相似文献
132.
Federico Ferrando-Castagnetto Enrique Macri Alejandro Silva Darío Padula Gastón Garcés 《Educación Médica》2019
Introduction
Although an objective structured clinical examination (OSCE) format has been applied in Uruguay since 2004, and providing reliable performance measures, perceptions of it properties and level of student satisfaction have not been determined.Objective
To evaluate the face validity of OSCE format as a contribution to its local feasibility study.Material and methods
At the end of the introductory clinical course, the sub-cohort enrolled at the University Hospital responded to a 28-item questionnaire aimed at exploring perceptions about the properties of the OSCE about the potential factors ‘design’ and ‘apparent validity’. After analysing the reliability of the original questionnaire, the questionnaire was refined in an attempt to provide a shorter and more reliable tool.Results
The original questionnaire showed good internal consistency (Cronbach alpha = 0.70), with a dominance of ‘agreement/total agreement’ opinions on authenticity of the stimuli, dynamic, relevance, and equity of the test. Students perceived organisational obstacles during the test, expressing disagreement to include some stations only aimed at assessing communication skills, and requiring personalised feedback sessions. The refined version of the questionnaire provides consistent measures on student perceptions and is a useful tool that can be widely applied. A discussion is presented on the contributions of this experience to a comprehensive feasibility study of the new format during curriculum transition.Conclusions
The OSCE is well evaluated by students at the end of the propaedeutic course, supporting its validity. Educational potentials of the new format should be exploited, providing effective feedback to students, clinical teachers, and institutions. 相似文献133.
Uterine smooth muscle tumors are usually spindle cell lesions, but a minority is composed of epithelioid cells. Foci of clear cells can be found in these latter tumors. Recently, it has been shown that some of these tumors can be positive for HMB45, and some authors have advocated calling these lesions perivascular epithelioid cell (PEC) tumors or PEComas. The case we describe here clearly shows that the so called PEC is just a smooth muscle cell capable of changing its immunophenotype. The patient involved is a 29-year-old black woman who was found to have an epithelioid leiomyosarcoma of the uterus in November 1995. She was treated with a simple hysterectomy and bilateral salpingo-oophorectomy. A metastatic lesion was found in her liver. She, therefore, also received chemotherapy and was free of disease until October 2002, when a recurrent tumor was detected in her spine. After undergoing resection of the lesion at 2 different times, in 2002 and 2003, the patient was treated with radiotherapy and is currently receiving chemotherapy. On microscopic examination, the tumor in the uterus and liver both proved to be an epithelioid leiomyosarcomas that was diffusely positive for smooth muscle actin. Approximately 15% of the cells had clear cytoplasm, but sections from 2 different blocks were completely negative for HMB45. However, although the tumors resected from the spine in 2002 and 2003 showed features similar to those of the uterine neoplasm, but with a lower percentage of cells positive for smooth muscle actin and more clear cells, several of the clear cells were positive for HMB45. To the best of our knowledge, this is the first case of a uterine smooth muscle cell tumor that became positive for HMB45 when it metastasized. 相似文献
134.
Taborda CP Nakaie CR Cilli EM Rodrigues EG Silva LS Franco MF Travassos LR 《Scandinavian journal of immunology》2004,59(1):58-65
The 43 kDa glycoprotein (gp43) of Paracoccidioides brasiliensis is the major diagnostic antigen of paracoccidioidomycosis (PCM), a prevalent fungal infection in South America. A 15-mer sequence from gp43, denominated P10, induced T-CD4+ T helper 1 cellular immune responses in mice of three different haplotypes and protected against intratracheal challenge by a virulent isolate of P. brasiliensis. In an attempt to improve delivery of P10, a promiscuous antigen also presented by human leucocyte antigen-DR alleles, aiming at immunotherapy, we synthesized a multiple antigen peptide with the protective T-cell epitope expressed in a tetravalent 13-mer analog of P10 (M10). M10 induced specific lymph node cell proliferation in mice preimmunized with peptides in complete Freund's adjuvant (CFA). In addition, M10 immunization without CFA significantly protected intratracheally infected mice. We conclude that M10 is a candidate for an anti-PCM vaccine. In this report we describe: (1) the synthesis of M10; (2) the induction of M10-elicited T-cell response and (3) in vivo protection of mice immunized with M10 and challenged by a virulent strain of P. brasiliensis. 相似文献
135.
Constitutional rearrangements of chromosome 22 as a cause of neurofibromatosis 2 总被引:2,自引:0,他引:2
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136.
Lobo Gatti L Agostinho Jn F De Lábio R Balbo Piason F Carlos Da Silva L Fagundez De Queiroz V Peres CA Barbieri D De Arruda Cardoso Smith M Marques Payão SL 《Clinical and experimental medicine》2003,3(3):166-172
Helicobacter pylori has been shown to be strongly associated with chronic gastritis, gastric and duodenal ulceration, and is a risk factor for gastric carcinoma. Histology, urease, culture, and polymerase chain reaction have been employed as for H. pylori diagnostic methods, pre and post treatment or during follow-up of dyspeptic adult individuals referred for endoscopy. In order to obtain a more-sensitive and specific method for H. pylori detection, we evaluated gastric body and antrum biopsies of 134 consecutive Brazilian consecutive dyspeptic children aged 1-16 years by rapid urease test, histology and polymerase chain reaction using two pairs of oligonucleotides. Our results indicated that polymerase chain reaction with Southern blotting and hybridization with specific chemiluminescent probes increased the number of positive H. pylori patients by 35%. The genotyping of H. pylori strains directly from gastric biopsy using the same nucleic acid methodology revealed that there is no association of chronic gastritis in our infant patients with vacA s1 and the presence of the cagA gene. These data suggest an initial infection of children with normal mucosa and probably others factors than vacA s1 genotype or the presence of the cagA gene are associated with the onset of gastric disease. Altogether, our results reinforce the need for using more sensitive diagnostic methods in order to understand the role of H. pylori in the genesis of gastric disease in children and its progression in adults. 相似文献
137.
Luiza Guilherme Ed cio Cunha Neto Guilherme Renesto Anna C. Goldberg Josely Chiarella Rachel Snitcowsky Ma. Helena Kiss Cl vis Silva Jorge Kalil 《Human immunology》1996,47(1-2):20
β-hemolytic streptococcal infection in developing countries still causes thousands of cases of Rheumatic Fever (RF). Molecular mimicry between streptococcal M protein (strep M) and heart components has been proposed as the triggering factor leading to autoimmunity in individuals with genetic susceptibility, which is linked to different HLA-DR alleles in different populations. In our hands, RF was significantly associated to HLA-DR7/53. Previous work in our lab has shown that heart-infiltrating T cells that simultaneously recognize strep M and heart proteins. Further, such T cells predominantly recognized the 81-103 strep M5 epitope. In this work, we analysed the proliferative response of peripheral blood mononuclear cells of 99 RF patients and 40 normal controls. Eighty-nine of the RF patients were HLA-typed. As among heart-infiltrating T cells, the 81-103 strep M5 protein epitope is the most frequently recognized epitope among RF PBMC (35.4%), against a 7.5% frequency of proliferation among normal controls (p=0.0018, chi square). However, the 81-103 epitope was as frequently recognized by HLA-DR7,53 positive as by negative individuals (45.2% vs 54.8%, respectively). Taken together, the results suggest that the 81-103 strep M5 epitope may be the immunodominant epitope, “promiscuously” recognized by T cells in a genetically diverse population. The demonstration that molecular mimicry is targeted to a discrete immunodominant “promiscuous” epitope in strep M5 may allow the development of a safe anti-streptococcal synthetic vaccine devoid of such epitopes. 相似文献
138.
Chest radiography in general practice: indications, diagnostic yield and consequences for patient management
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Anouk M Speets Yolanda van der Graaf Arno W Hoes Sandra Kalmijn Alfred PE Sachs Matthieu JCM Rutten Jan Willem C Gratama Alexander D Montauban van Swijndregt Willem PThM Mali 《The British journal of general practice》2006,56(529):574-578
BACKGROUND: Chest radiography (CXR) is frequently performed in Western societies. There is insufficient knowledge of its diagnostic value in terms of changes in patient management decisions in primary care. AIM: To assess the influence of CXR on patient management in general practice. DESIGN OF STUDY: Prospective cohort study. SETTING: Seventy-eight GPs and three general hospitals in the Netherlands. METHOD: Patients (n = 792) aged > or =18 years referred by their GPs for CXR were included. The main outcome was change in patient management assessed by means of questionnaires filled in by GPs before and after CXR. RESULTS: Mean age of the patients was 57.3+/-16.2 years and 53% were male. Clinically relevant abnormalities were found in 24% of the CXRs. Patient management changed in 60% of the patients following CXR. Main changes included: fewer referrals to a medical specialist (from 26 to 12%); reduction in initiation or change in therapy (from 24 to 15%); and more frequent reassurance (from 25 to 46%). However, this reassurance was not perceived as such in a quarter of these patients. A change in patient management occurred significantly more frequently in patients with complaints of cough (67%), those who exhibited abnormalities during physical examination (69%), or those with a suspected diagnosis of pneumonia (68%). CONCLUSION: Patient management by the GP changed in 60% of patients following CXR. CXR substantially reduced the number of referrals and initiation or change in therapy, and more patients were reassured by their GP. Thus, CXR is an important diagnostic tool for GPs and seems a cost-effective diagnostic test. 相似文献
139.
Distinct Leishmania braziliensis isolates induce different paces of chemokine expression patterns 总被引:1,自引:0,他引:1
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Teixeira MJ Fernandes JD Teixeira CR Andrade BB Pompeu ML Santana da Silva J Brodskyn CI Barral-Netto M Barral A 《Infection and immunity》2005,73(2):1191-1195
Inflammatory events during Leishmania braziliensis infection in mice were investigated. Large lesions were directly correlated with the inflammatory reaction but not with parasite burden. Different L. braziliensis strains induce different paces of chemokine expression patterns, leading to diverse cell recruitment and differential inflammatory responses. 相似文献
140.
S. M. S. R. Araújo C. C. Silva S. G. Pompolo F. Perfectti J. P. M. Camacho 《Chromosome research》2002,10(7):607-613
Extensive variation in the size of the short (heterochromatic) arm of chromosome 14 was found in the wasp Trypoxylon (Trypargilum) albitarse. Ten different variants were differentiated by size and C-banding pattern. Fluorescent in-situ hybridization (FISH) revealed that ribosomal DNA in this species is clustered in the darkly C-banded parts of the heterochromatic
short arm of chromosome 14. On this basis, we got an indirect estimate of the amount of rDNA from the area of these dark C-bands.
The significant absence in males of the three chromosome variants with lower amounts of rDNA indicates that these three variants
are lethal in this sex, and suggests the existence of a threshold marking the minimum amount of rDNA which is tolerable in
haploidy. This implies about 4% genetic load in the population caused by variation in rDNA amount.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献