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91.
The cytological evaluation of ovarian cystic fluid using ThinPrep has not been reported. To determine the diagnostic accuracy of ThinPrep cytology in distinguishing between benign and nonbenign ovarian cystic lesions, we examined 65 fluid samples aspirated during intraoperative consultation with subsequent histologic correlation. One ThinPrep slide was prepared from each sample aspirated from surgically removed ovarian cystic masses and reviewed blindly by a panel of three cytopathologists. The parameters used in cytological evaluation were cellularity, cell types, cellular arrangement, and background. Four samples were acellular and excluded from the study. The consensus cytologic diagnoses were compiled for 61 cases which were assigned to one of the following diagnostic categories: negative for malignant cells (40 cases), atypical cytology (13 cases), and suspicious or positive for malignancy (8 cases). Histologic correlation of the cytological benign/negative cases showed that 26/40 (65%) were histologically benign and 14/40 were false-negative (35%, 5 carcinomas and 9 borderline tumors) with 10 of these cases being mucinous tumors. Most false-negative cytologic samples (11/14 or 79%) did not have an epithelial component. Of the 21 cytological nonbenign diagnoses (atypical/suspicious/positive), 15 (71%) were confirmed on histology (10 carcinomas and 5 borderline tumors). However, a nonbenign cytologic diagnosis was rendered in 6 histologically benign cases, including 2 serous cystadenomas, 1 mucinous cystadenoma, 1 serous cystadenofibroma, 1 endometriosis, and 1 corpus luteal cyst. The diagnostic sensitivity by ThinPrep evaluation of ovarian cystic masses is 81% (26/32) for benign and 52% (15/29) for nonbenign lesions. Our results concluded that ThinPrep examination of ovarian cystic fluid is not accurate in distinguishing benign from malignant cysts, given the significant number of false-negative diagnoses. Major contributing factors include sparse cellularity of the fluid samples and mucinous differentiation of the tumors. 相似文献
92.
Maria Cristina Machado Motta Maurilio José Soares Wanderley de Souza 《Parasitology research》1993,79(7):551-558
Crithidia oncopelti, C. deanei, andC. desouzai are flagellates of the Trypanosomatidae family that present bacterium-like endosymbionts in their cytoplasm. Direct and indirect lectin-gold labeling techniques were used at the electron microscopic level in Lowicryl K4M-embedded cells to demonstrate the presence of intracellular lectin-binding sites. We used the lectinsUlex europaeus I, Griffonia simplicifolia II, Ricinus communis I, Arachis hypogaea, G. simplicifolia I, Wistaria floribunda, Limulus polyphemus, andCanavalia ensiformis, which recognize -l-fucose, - and -N-acetylglucosamine, -galactose and -N-acetylgalactosamine, -galactose, -galactose, -N-acetylgalactosamine, sialic acid and -d-mannose, and -d-glucose residues, respectively. The nucleus was the cellular structure most frequently labeled by the lectins. The Golgi complex was seldom labeled, whereas the endoplasmic reticulum and the flagellar pocket presented a large number of binding sites. Symbionts had their two unit membranes weakly labeled by the different lectins but displayed no labeling of the space between the membranes. 相似文献
93.
Claudia Teresa Vieira de Souza Theresa Diaz Frits Sutmoller Francisco Inácio Bastos 《Journal of acquired immune deficiency syndromes (1999)》2002,29(1):95-100
To evaluate the relation between illicit drug use, sexual practices, and socioeconomic status, we analyzed data from the baseline interview of a cohort of 675 men who have sex with men conducted from 1994 to 1999 in Rio de Janeiro, Brazil. Bivariate analyses of factors associated with crack/cocaine use with sex revealed that men who reported crack/cocaine use were significantly ( p <.05) more likely than men who did not report drug use to be unemployed (42.7% vs. 29.1%), to have an income of <$250 per month (70.7% vs. 60.9%), to have <8 years of education (69.5% vs. 50.9%), to report bisexual activity (81.7% vs. 41.7%), and to engage in commercial sex (72.0% vs. 37.9%). Multivariate analysis of factors associated with unprotected anal sex with casual male partners in the last 6 months demonstrated that the following variables were associated with this outcome: an income <$250 per month (adjusted odds ratio [AOR] = 1.73, 95% confidence interval [CI]: 1.04-2.87), less than 8 years of education (AOR = 2.21, CI: 1.38-3.53), a greater sense of vulnerability (AOR = 2.58, CI: 1.54-4.33), a willingness to participate in vaccine trials (AOR = 1.91, CI: 1.20-3.05), and use of crack/cocaine (AOR = 1.91, CI: 1.05-3.46). Our findings suggest that HIV prevention programs for these men need to address drug use and how drug use may influence sexual behaviors. 相似文献
94.
S. I. Aguiar I. Serrano F. R. Pinto J. Melo-Cristino M. Ramirez 《Clinical microbiology and infection》2008,14(9):835-843
The pneumococcal seven-valent conjugate vaccine (PCV7) has been administered in Portugal since late 2001 through the private sector. To evaluate the impact of PCV7 use, the serotypes and antimicrobial susceptibility of pneumococci causing invasive disease in Portugal during 2003–2005 were determined and compared with available data for the period 1999–2002. Changes in serotype distribution compatible with the introduction of PCV7 were shown for children ≤5 years of age from 2003 onwards and for adults from 2004 onwards. PCV7 use with coverage of 43% of children with four doses in the 2004 birth cohort, although substantially below universal coverage, seems to have contributed to greatly reducing the proportion of invasive infections due to vaccine serotypes 4, 6B, 14 and 23F. Similarly, significant indirect effects on the serotype distribution of pneumococci causing infections in adults were noted, with reductions in the proportion of invasive infections caused by serotypes 4, 5 and 14. These changes were accompanied by an increase in the proportion of two non-vaccine serotypes: 19A isolates in all age groups and 7F isolates in adults. Whereas serotypes 6B, 14 and 19A were associated with multidrug resistance, isolates expressing serotypes 4 and 7F were fully susceptible for the most part. There were no changes in the proportion of resistant isolates within each serotype and, in spite of the changes in serotype prevalence, there was not an overall reduction in the proportion of infections caused by resistant pneumococci. 相似文献
95.
5-HT1A dysfunction in borderline personality disorder 总被引:2,自引:0,他引:2
Hansenne M Pitchot W Pinto E Reggers J Scantamburlo G Fuchs S Pirard S Ansseau M 《Psychological medicine》2002,32(5):935-941
BACKGROUND: A number of challenge studies have reported abnormalities of serotonergic function in borderline personality disorder (BPD). There are, however, problems with the pharmacological probes used in these studies since fenfluramine and m-CPP are not only serotonergic agents but also induce release of catecholamines, particularly dopamine. Therefore, we tested whether subjects with BPD showed a blunted prolactin (PRL) response to flesinoxan, a highly potent and selective 5-HT1A agonist. METHODS: Flesinoxan challenge test was carried out in 20 BPD in-patients and 20 healthy controls matched for gender but not for age. Since 16 BPD in-patients exhibited major depressive co-morbidity, a group of 20 depressed in-patients matched for gender but not for age was also included. RESULTS: BPD in-patients exhibited blunted PRL responses as compared to controls, whereas depressed in-patients did not differ from controls. Moreover, PRL responses were lower among BPD in-patients than among depressed in-patients. Among the BPD in-patients, PRL responses to flesinoxan were lower in patients with past history of suicide attempts (N = 8) than in those with a negative history. CONCLUSIONS: The results show major involvement of serotonergic function in BPD and are consistent with previous studies linking lower serotonergic activity with impulsivity. More particularly, our data suggest that BPD is characterized by lower 5-HT1A receptor sensitivity. Moreover, the data support the involvement of 5-HT1A activity in suicidal behaviour. However, this conclusion is limited because other hormonal responses such as ACTH and cortisol were not assessed, and because BPD was assessed by a self-report questionnaire and not a structured clinical interview. 相似文献
96.
Monocytoid B-cell lymphoma with bone marrow and peripheral blood involvement at presentation 总被引:3,自引:0,他引:3
A Carbone A Gloghini A Pinto V Attadia V Zagonel R Volpe 《American journal of clinical pathology》1989,92(2):228-236
A case of malignant lymphoma showing in a lymph node the characteristic morphologic features of the so-called monocytoid B-cell lymphoma (MBCL) is described. This case differs from the reported cases in the literature because atypical cells were observed in the bone marrow biopsy and marrow and peripheral blood smears that were obtained from the patient, a 61-year-old man, during the staging procedures. Lymphocyte surface marker studies on peripheral blood by flow cytometry and DNA analysis revealed a monoclonal population of lambda-positive lymphocytes. The immunophenotype of MBCL cells was studied both in paraffin-embedded lymph node sections by immunoperoxidase method and in peripheral blood by flow cytometric analysis; the cells expressed the SIg with lambda light chain restriction and the HLA-DR antigen; they also had positive results for B-cell-associated antigens, including LN1, LN2, CD 20, CD 22, CD 19, CD 9 but not CD 21, CD 24, and CD 10, T-cell-associated antigens and monocytic markers. In addition, they had negative results for CD 25, CD 38, PCA-1. This report emphasizes that in MBCL, peripheral and marrow involvement may occur at presentation analogous to other low-grade B-cell lymphomas. The immunophenotypic characteristics of MBCL cells, though not pathognomonic, are considered to be helpful in differentiating them from circulating cells of other B-cell lymphomas. 相似文献
97.
An antigen-competitive enzyme-linked immunosorbent assay (Ag-C-ELISA) was developed for the detection of infectious bronchitis virus (IBV) antigens, M41 strain, in tissues from experimentally infected chickens, or in allantoic fluid harvested from inoculated embryonated eggs. The detection limit of IBV in the Ag-C-ELISA was 104.1 median embryo infective doses (EID50)/well. Tracheal and lung samples from chickens vaccinated with 102.5 EID50 of live attenuated infectious bronchitis (H120) vaccine were negative in the direct detection Ag-C-ELISA. The results indicate that the Ag-C-ELISA has the potential to detect IBV, either directly in tissue samples or when combined with the passage of material in embryonated eggs, thereby constituting an alternative method for the diagnosis of IBV. 相似文献
98.
Alvaro P Pinto AP Felipe F B Tuon Luiz Fernando Bleggi Torres Luiz Martins Colla?o 《Diagnostic cytopathology》2002,26(1):15-18
The present study sought possible factors leading to the cytological diagnosis of atypical squamous cells of uncertain significance (ASCUS) in cases of high-grade squamous intraepithelial lesions (HSIL). Based on retrospective histopathological analysis of loop electrical excision procedure (LEEP) products that diagnosed HSIL, two study groups were randomly selected. The first was consisted of cases with two consecutive Papanicolaou (Pap) smears with the diagnosis of ASCUS. The second (control) group was represented by cases diagnosed as HSIL by cytology. From the Pap smears diagnosed as ASCUS, the sampling limitations was different from control group (P < 0.05). The median size of the largest lesion in each case with ASCUS was 2.66 mm (+/- 1.71 mm). In the control group, the median size of the largest lesion was 5.15 mm (+/-2.58 mm) (P < 0.05). The size of the lesion and sample limitations led patients with cervical intraepithelial neoplasms to be diagnosed as ASCUS for two consecutive times, after a 6-mo period. 相似文献
99.
Fbio A. Kunrath Fbio F. Mota Osvaldo L. Casagrande Raquel S. Mauler Roberto F. de Souza 《Macromolecular chemistry and physics.》2002,203(17):2407-2411
The polymerization of ethylene in the presence of 1,4‐bis(2,6‐diisopropylphenyl)acenaphthenediiminenickel(II) dichloride ( 1 ) and methylaluminoxane (MAO) gives hyperbranched polyethylene (HBPE) in appropriate reaction conditions. The system 1 /MAO is active in solvents like toluene or hexane at temperatures as high as 80 °C and ethylene pressures ranging from 1 to 15 atm. The polyethylenes obtained show high molecular weights (up to 467 kg · mol?1) and more than 218 branches per 1 000 backbone carbon atoms, qualifying these materials as hyperbranched. Dynamic‐mechanical thermal analysis (DMTA) of these materials shows high β‐transitions, directly related to the branch content of these polyethylenes.
100.
Lamerdin JE Yamada NA George JW Souza B Christian AT Jones NJ Thompson LH 《Mutagenesis》2004,19(3):237-244
The human FANCG/XRCC9 gene, which is defective in Fanconi anemia complementation group G (FA-G) cells, was first cloned by genetic complementation of the mitomycin C (MMC) sensitivity of CHO mutant UV40. The CHO NM3 mutant was subsequently assigned to the same complementation group. The parental AA8 CHO cells are hemizygous at the FancG locus, and we identified frameshift mutations that result in N-terminal truncations of the protein in both UV40 and NM3. Hypersensitivity to DNA cross-linking agents, such as MMC, typically characterizes FA cells. By introducing the native CHO FancG gene into mutant NM3, we demonstrate that hamster FancG fully corrects the 3-fold sensitivity to methyl methanesulfonate (MMS) as well as the 10-fold sensitivity to MMC, whereas resistance to ionizing radiation did not increase appreciably. In contrast, hamster cDNA transformants showed incomplete correction for both MMC and MMS sensitivity. The constitutively expressed FancG protein is present in the cytoplasmic, nuclear and chromatin fractions. FancG protein levels and subcellular localization do not change appreciably as a function of cell cycle position. Our results are consistent with roles of FancG in both the nuclear and cytoplasmic compartments to maintain genomic stability in response to various genotoxic agents. 相似文献