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61.
Francesco Alfredo Zito Paolo Verderio Giovanni Simone Vito Angione Paola Apicella Simonetta Bianchi Antonio Felix Conde Omar Hameed Julio Ibarra Antony Leong Natale Pennelli Ezio Pezzica Vania Vezzosi Vincenzo Ventrella Sara Pizzamiglio Angelo Paradiso Ian Ellis 《Histopathology》2010,56(6):720-726
Zito F A, Verderio P, Simone G, Angione V, Apicella P, Bianchi S, Conde A F, Hameed O, Ibarra J, Leong A, Pennelli N, Pezzica E, Vezzosi V, Ventrella V, Pizzamiglio S, Paradiso A & Ellis I(2010) Histopathology 56, 720–726Reproducibility in the diagnosis of needle core biopsies of non‐palpable breast lesions: an international study using virtual slides published on the world‐wide web Aims: To conduct an internet‐based study using virtual slides (VS) of sterotactic core biopsy specimens of non‐palpable breast lesions in order to evaluate interobserver reproducibility between pathologists. Methods and results: A total of 18 breast lesions, determined to be histologically complex by two pathologists, were selected. Digitized VSs were then created using QuickTime Virtual Reality technology (Apple, Cupertino, CA, USA) and posted on the world‐wide web. In all, 10 pathologists completed the evaluations of 18 VSs using the five diagnostic categories (B1–B5) from the European guidelines for quality assurance in breast cancer screening and diagnosis. Their results were compared with those of every other participating pathologist, and were then individually compared with the results of a highly experienced breast pathologist (referee). Of the 18 cases, 10 (56%) were classified by the referee as borderline (B3 and B4). Comparisons with reference values showed a less than satisfactory level of reproducibility (median κw = 0.60). As regards interobserver reproducibility, results showed that, in general, the level of agreement was not satisfactory (median κw = 0.53). Conclusions: Overall, the findings are comparable to those quality control studies using circulating slides when analysis is done on borderline cases. 相似文献
62.
This report describes the case history of a middle-aged lady who presented with symptoms and signs over one year leading to a diagnosis of multiple sclerosis. During one of her relapses, she developed trismus--an association that has not been described before in multiple sclerosis. 相似文献
63.
Vania M C Silva Antonio Jose Ledo A Cunha Afranio L Kritski 《Infection control and hospital epidemiology》2002,23(10):591-594
OBJECTIVE: To describe the cumulative incidence of and risk factors for tuberculosis (TB) infection among medical students. DESIGN: In 1999, a cohort study of medical students with negative results (induration < 10 mm) on tuberculin skin test (TST) was performed. Students who had undergone two-step testing in 1998 were retested. SETTINGS: University and teaching hospital and referral center for TB and acquired immunodeficiency syndrome, and the Health Sciences Building of the Medical School of the Federal University of Rio de Janeiro, Brazil. PARTICIPANTS: A sample of 618 consecutive medical students with negative TST results who had been tested 12 months before were approached. Information about sociodemographic characteristics, bacille Calmette-Guérin vaccination history, and potential exposures to TB was obtained using a standardized questionnaire. Four hundred fourteen (67%) students completed the study. Students were at two different levels of their training programs (juniors = no contact with patients; seniors = intensive contact with patients). RESULTS: Of 414 participants, 16 (3.9%; 95% confidence interval, 1.06% to 12.1%) had converted to a positive reaction after 1 year. In a multivariate logistic regression analysis, higher level of clinical training was confirmed to be an independent factor associated with TST conversion (odds ratio, 4.77; 95% confidence interval, 1.01 to 22.46; P= .048). CONCLUSION: Senior medical students are at increased risk of Mycobacterium tuberculosis infection in this setting. Therefore, a program of routine tuberculin skin testing and specific TB infection control guidelines are needed for this population. 相似文献
64.
A Sapone L Pozzetti D Canistro M Broccoli G Bronzetti G Potenza A Affatato G L Biagi G Cantelli-Forti M Paolini 《Food and chemical toxicology》2005,43(1):173-183
This work aimed to investigate whether the insecticide acephate (125 or 250 mg/kg b.w.) or diflubenzuron (752 or 1075 mg/kg b.w.), two of the most widely used pesticides worldwide, impairs CYP-linked murine metabolism in liver, kidney and lung microsomes after repeated (daily, for three consecutive days) i.p. administration. The regio- and stereo-selective hydroxylation of testosterone was used as multibiomarker of different CYP isoforms. Both gender and tissue specific effects were observed. Lung was the most responsive tissue to induction by lower diflubenzuron dose, as exemplified by the marked increase of testosterone 7alpha-hydroxylation (CYP2A) (up to 13-fold) in males. Higher dose produced a generalized inactivation. At the lower dose acephate induced 6beta- (CYP3A1/2, liver) as well as 2beta- (CYP2B1/2, kidney) hydroxylase activities ( approximately 5 and approximately 4-fold increase, respectively) in males. In females, a marked suppression of the various hydroxylations was observed. At 250 mg/kg of acephate, animals did not survive. Induction of the most affected isoforms was sustained by immunoblotting analysis. Corresponding human CYP modulations might disrupt normal physiological functions related to these enzymes. Furthermore, the co-mutagenic and promoting potential of these pesticides, phenomena linked to CYP upregulation (e.g. increased bioactivation of ubiquitous pollutants and generation of oxygen free radicals) are of concern for a more complete definition of their overall toxicological potential. 相似文献
65.
Alexssandro G. Becker Bibiana S. Moraes Charlene C. Menezes Vania L. Loro Danilo R. Santos Jos M. Reichert Bernardo Baldisserotto 《Ecotoxicology and environmental safety》2009,72(6):1734-1739
We investigated how pesticide contamination of water affects the metabolism of the silver catfish, Rhamdia quelen, by studying fish maintained at two sites with low and high anthropic activity (Lino Creek, southern Brazil). Several pesticides were found at both stream sites. After 30 days plasma glucose levels were higher in fish exposed to water in the low anthropic activity site than those exposed to water in the high anthropic activity site. Plasma K+ levels, however, were lower after exposure to low anthropic water than after exposure to high anthropic water. Moreover, values of hepatic glycogen, muscle lactate and protein were higher, but glycogen and protein of the kidney were lower in fish exposed to water at the high anthropic activity site. Our results show that these fish can be used as pesticide toxicity indicators in streams near agricultural fields. 相似文献
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68.
Kátia Martins Lopes de Azevedo Sérgio Setúbal Vania Gloria Silami Lopes Luiz Antônio Bastos Camacho Solange Artimos de Oliveira 《The Brazilian journal of infectious diseases》2010,14(2):186-189
We report the occurrence of congenital toxoplasmosis in three infants born to HIV infected women who had high anti-toxoplasma IgG and negative IgM during pregnancy. We briefly reviewed available literature and discussed the possible transmission mechanisms of congenital toxoplasmosis among HIV infected pregnant women. Serum samples were tested for Toxoplasma gondii IgM and IgG antibodies using commercial enzyme immunoassay and IgG-avidity tests. In the first case, fetal death occurred at 28th week of gestation. In the second case, congenital toxoplasmosis was diagnosis at 6th month of life; and in the third case, an HIV-infected newborn, congenital toxoplasmosis was asymptomatic. These cases point out to the possibility of enhanced maternal-fetal transmission of T. gondii infection by HIV-infected women chronically infected, which may have important public health consequences, considering that increasing frequency of HIV-infection has been observed among women of childbearing age around the world. 相似文献
69.
Cattaneo R Clasen B Lucia Loro V de Menezes CC Moraes B Santi A Toni C de Avila LA Zanella R 《Journal of applied toxicology : JAT》2011,31(7):626-632
Cyprinus carpio fish were exposed to penoxsulam (Ricer) in field conditions. The experiment in the rice field was carried out for 7, 21 and 72 days. Oxidative stress parameters and antioxidant profile were studied. The acetylcholinesterase (AChE) enzyme activity in the brain was increased after 7 days and reduced after 21 and 72 days of the experiment in the rice field. The AChE activity in muscle was reduced only after 72 days of exposure. Thiobarbituric acid-reactive species were increased in the liver, brain and muscle at 7 days of the trial, reduced at 21 days in the brain and unaltered after 72 days of exposure in muscle. However, an increase in this parameter in the brain and liver was observed. Liver glutathione S-transferase was reduced at 7 days, unchanged at 21 days and increased after 72 days of exposure. Catalase of the liver changed only in the second experimental period, when it was reduced. Liver protein carbonyl was reduced at 7 days and increased at 21 and 72 days of exposure. This study shows long-term effects of rice herbicide at environmentally relevant concentrations on toxicological parameters in different tissues (brain, muscle and liver) of Cyprinus carpio. 相似文献
70.