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51.
To investigate the diagnostic accuracy and to characterize the findings in false-negative cases, the results of cervicovaginal cytology in 56 adenocarcinomas and 25 adenosquamous carcinomas (42 cervical, 36 endometrial, 2 metastatic and 1 arising synchronously from both cervix and endometrium) were reviewed, including review of the actual slides in 56 cases. Overall, 80% of the initial cytologic diagnoses resulted in diagnostic curettage (i.e., cytology was effectively positive); 84% of the postreview diagnosis were effectively positive. Nine cytology slides showed no malignant cells; eight of these negative smears showed repair, five were atrophic, two showed a high estrogen effect and one had enlarged atypical bare nuclei. These false-negative diagnoses were associated with an endometrial primary site (P less than .01), endometrioid histology (P less than .005), low-grade or intermediate-grade histology (P less than .005), small size of tumor (P less than .05) and absence of cervical involvement (P less than .005) in those cases in which a hysterectomy was performed. False-negative diagnoses were not associated with an absence of endocervical cells or with scanty cellularity. Of 39 cervical and 28 endometrial carcinomas with a positive cytologic diagnosis (initially or after review of the available slides), cytology correctly identified the primary site in 18% and 54% of the cases, respectively. Cytology incorrectly classified the anatomic site of four cervical and three endometrial carcinomas and considered one case arising in both the endometrium and cervix to be endometrial. Routine cervicovaginal cytology does have a role in screening for uterine glandular carcinoma; to maximize its diagnostic sensitivity, we suggest using a recommendation for curettage in the report of positive cases so that all of the varied cytologic diagnoses associated with glandular carcinomas will receive a uniform clinical response. In those cases with preserved cancer cells, a correlation can be made with the histologic type of the carcinoma, rather than with the anatomic site. 相似文献
52.
G. D. S. Seger L. D. S. Duarte V. J. Debastiani A. Kindel J. A. Jarenkow 《Plant biology (Stuttgart, Germany)》2013,15(5):858-867
Understanding how species traits evolved over time is the central question to comprehend assembly rules that govern the phylogenetic structure of communities. The measurement of phylogenetic signal (PS) in ecologically relevant traits is a first step to understand phylogenetically structured community patterns. The different methods available to estimate PS make it difficult to choose which is most appropriate. Furthermore, alternative phylogenetic tree hypotheses, node resolution and clade age estimates might influence PS measurements. In this study, we evaluated to what extent these parameters affect different methods of PS analysis, and discuss advantages and disadvantages when selecting which method to use. We measured fruit/seed traits and flowering/fruiting phenology of endozoochoric species occurring in Southern Brazilian Araucaria forests and evaluated their PS using Mantel regressions, phylogenetic eigenvector regressions (PVR) and K statistic. Mantel regressions always gave less significant results compared to PVR and K statistic in all combinations of phylogenetic trees constructed. Moreover, a better phylogenetic resolution affected PS, independently of the method used to estimate it. Morphological seed traits tended to show higher PS than diaspores traits, while PS in flowering/fruiting phenology depended mostly on the method used to estimate it. This study demonstrates that different PS estimates are obtained depending on the chosen method and the phylogenetic tree resolution. This finding has implications for inferences on phylogenetic niche conservatism or ecological processes determining phylogenetic community structure. 相似文献
53.
Chen L Hainrichson M Bourdetsky D Mor A Yaron S Baasov T 《Bioorganic & medicinal chemistry》2008,16(19):8940-8951
A new pseudo-disaccharide NB23 with a 3',4'-methylidene protection was designed and its properties were evaluated in comparison to other two structurally related pseudo-disaccharides. The basicity of the 2'-amine was found to be well correlated to acute toxicity data in mice: the increase in the basicity is associated with the toxicity increase. Based on these data, a new pseudo-trisaccharide NB45 was constructed. NB45 exhibited significant antibacterial activity while at the same time retained low acute toxicity. 相似文献
54.
Gambarino S Costa C Astegiano S Piasentin EA Segoloni GP Cavallo R Bergallo M 《Molecular biotechnology》2011,49(2):151-158
Polyomavirus BK latently persist in different sites, including the renourinary tract, and may reactivate causing nephropathy
in renal transplant recipients or hemorrhagic cystitis in bone marrow recipients. Based on the sequence of the VP1 gene, four
genotypes have been described, corresponding to the four serologically differentiated subtypes I–IV, with different prevalence
and geographic distribution. In this study, the development and clinical validation of four different Real-Time PCR assays
for the detection and discrimination of BKV genotypes as a substitute of DNA sequencing are described. 379 BK VP1 sequences,
belonging to the main four genotypes, were aligned and “hot spots” of mutation specific for all the strains or isolates were
identified. Specific primers and probes for the detection and discrimination of each genotype by four Real-Time PCR assays
were designed and technically validated. Subsequently, the four Real-Time PCR assays were used to test 20 BK-positive urine
specimens from renal transplant patients, and evidenced a prevalence of BK genotype I, as previously reported in Europe. Results
were confirmed by sequencing. The availability of a rapid and simple genotyping method could be useful for the evaluation
of BK genotypes prevalence and studies on the impact of the infecting genotype on viral biological behavior, pathogenic role,
and immune evasion strategies. 相似文献
55.
56.
Mariana Mayer-Pinto Barbara L. Ignacio Maria T. M. Széchy Mariana S. Viana Maria P. Curbelo-Fernandez Helena P. Lavrado Andrea O. R. Junqueira Eduardo Vilanova Sérgio H. G. Silva 《PloS one》2012,7(10)
Several approaches have been proposed to assess impacts on natural assemblages. Ideally, the potentially impacted site and multiple reference sites are sampled through time, before and after the impact. Often, however, the lack of information regarding the potential overall impact, the lack of knowledge about the environment in many regions worldwide, budgets constraints and the increasing dimensions of human activities compromise the reliability of the impact assessment. We evaluated the impact, if any, and its extent of a nuclear power plant effluent on sessile epibiota assemblages using a suitable and feasible sampling design with no ‘before’ data and budget and logistic constraints. Assemblages were sampled at multiple times and at increasing distances from the point of the discharge of the effluent. There was a clear and localized effect of the power plant effluent (up to 100 m from the point of the discharge). However, depending on the time of the year, the impact reaches up to 600 m. We found a significantly lower richness of taxa in the Effluent site when compared to other sites. Furthermore, at all times, the variability of assemblages near the discharge was also smaller than in other sites. Although the sampling design used here (in particular the number of replicates) did not allow an unambiguously evaluation of the full extent of the impact in relation to its intensity and temporal variability, the multiple temporal and spatial scales used allowed the detection of some differences in the intensity of the impact, depending on the time of sampling. Our findings greatly contribute to increase the knowledge on the effects of multiple stressors caused by the effluent of a power plant and also have important implications for management strategies and conservation ecology, in general. 相似文献
57.
The olive fly (Bactrocera oleae) is the most important olive tree (Olea europaea) pest. In the Mediterranean basin, where 98?% of its main hosts are concentrated, it causes major agricultural losses, due to its negative effect on production and quality of both olive and olive oil. Previous phylogeographic analyses have established that Mediterranean olive fly populations are distinct from other Old World populations, but did not agree on the specific population substructure within this region. In order to achieve a higher resolution of the diversity of olive fly populations, particularly in Central and Western Mediterranean (home to 70?% of the world production), we comparatively analyzed a set of samples from Portugal in the context of published mitochondrial sequences across the species' worldwide range. Strong evidence of population substructure was found in the Central and Western Mediterranean area, with two clearly separate phylogenetic branches. Together with previously published data, our results strongly support the existence of at least three distinct Mediterranean populations of the olive fly, raise the possibility of additional regional substructure and suggest specific avenues for future research. This knowledge can be instrumental in the development of better management and control strategies for a major pest of Mediterranean agriculture. 相似文献
58.
Andersen T Carstensen J Hernández-García E Duarte CM 《Trends in ecology & evolution》2009,24(1):49-57
There is an apparent gap between the prominence of present theoretical frameworks involving ecological thresholds and regime shifts, and the paucity of efforts to conduct simple tests and quantitative inferences on the actual appearance of such phenomena in ecological data. A wide range of statistical methods and analytical techniques are now available that render these questions tractable, some of them even dating back half a century. Yet, their application has been sparse and confined within a narrow subset of cases of ecological regime shifts. Our objective is to raise awareness on the range of techniques available, and to their principles and limitations, to promote a more operational approach to the identification of ecological thresholds and regime shifts. 相似文献
59.
Marcelo Rodrigues Thales H. F. Costa Reginaldo Alves Festucci-Buselli Luzimar Campos Silva Wagner Campos Otoni 《In vitro cellular & developmental biology. Plant》2012,48(1):67-72
In vitro propagation of neem (Azadirachta indica A. Juss.) may offer an efficient alternative to seed propagation of this species. For optimization of in vitro propagation, different basal salt formulations, growth regulators, and culture container sealants (polytetrafluoroethylene hydrophobic membranes [PTFE]) were evaluated. Nodal segments cultured on Murashige and Skoog (MS) medium showed the highest shoot formation per explant (1.67). Explants cultured in flasks containing MS medium with 0.5 mg L−1 benzyladenine, 0.5 mg L−1 kinetin, and 0.05 mg L−1 naphthaleneacetic acid, and sealed with two PTFE membranes, produced the highest number of shoots (4.04). In contrast, explants cultured in flasks without membranes showed leaf chlorosis and senescence. For plant recovery, regenerants were acclimatized in a substrate of coconut fiber and eucalyptus bark (1:1) and showed 80% survival. Our results indicated that the use of flasks with vents was beneficial for in vitro propagation of this important plant. 相似文献
60.
Ernetti Julia R. Boschetti Joana P. Delazeri Francieli De Bastiani Veluma I. M. Pontes Mariana R. Ribeiro Luisa P. Lingnau Rodrigo Toledo Luís Felipe Lucas Elaine M. 《Hydrobiologia》2020,847(16):3355-3364
Hydrobiologia - Pithecopus rusticus is an endemic amphibian restricted to the type locality, in southern Brazil, and possibly endangered to extinction, due to habitat degradation. However, an... 相似文献