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141.
OBJECTIVE: To evaluate the performance of a new, manual, simplified liquid-based system, DNA-Citoliq (Digene Brasil), employed under routine conditions as compared to conventional smears collected from six collaborating private laboratories. METHODS: A panel of cytopathologists, who served as the gold standard diagnosis, adjudicated discordant opinions. RESULTS: Of 3206 pairs of slides considered valid for comparison, there were 3008 in full agreement (93.8%), 112 (3.5%) with one diagnostic category discrepancies, and 86 (2.7%) discordant cases. Among the 288 borderline+ by either method, DNA-Citoliq detected abnormalities in 243 (84.4%), and conventional smears (CS) detected abnormalities in 178 (61.8%) (McNemar test, P < 0.000), a 36.5% increased detection of borderline+ cases. CONCLUSIONS: For mild dyskaryosis, DNA-Citoliq detected 176 cases and CS 125 cases (McNemar test, P < 0.000); and for moderate+severe dyskaryosis 66 versus 32 cases respectively (McNemar test, P < 0.000).  相似文献   
142.
The aim of the present study was to investigate the possible endogenous storage of photosensitive nitric oxide, and also to examine the relaxant effect of NO released from the compound by UV light irradiation. Aorta was isolated from rats and the endothelium was mechanically removed. Denuded aortic rings pre-contracted with prostaglandin F(2alpha) responded with relaxation to UV light irradiation. The first stimulation produced the greatest response that decreased until complete disappearance. After this, the addition of the compound in the absence of light did not produce any response. However, in the presence of UV light irradiation, the complex trans-[RuCl([15]aneN4)NO]2+ induced 100% relaxation. After incubation with the nitric oxide scavenger, oxyhaemoglobin, this relaxation was completely abolished. In PGF2(2alpha)-pre-contracted aortas, the time to reach maximum relaxation was only 50s. Taken together, these results suggest that preformed endogenous nitric oxide stores exist in the denuded rat aorta, and that they are sensitive to UV light. The photo-induction of the complex trans-[RuCl([15]aneN4NO]2+ induces complete aorta relaxation, which is due to release of nitric oxide in the extracellular medium.  相似文献   
143.
Vitamin C (in the reduced form ascorbate or in the oxidized form dehydroascorbate) is implicated in signaling events throughout the central nervous system (CNS ). In the retina, a high‐affinity transport system for ascorbate has been described and glutamatergic signaling has been reported to control ascorbate release. Here, we investigated the modulatory role played by vitamin C upon glutamate uptake and N ‐methyl‐d ‐aspartate (NMDA ) receptor activation in cultured retinal cells or in intact retinal tissue using biochemical and imaging techniques. We show that both forms of vitamin C, ascorbate or dehydroascorbate, promote an accumulation of extracellular glutamate by a mechanism involving the inhibition of glutamate uptake. This inhibition correlates with the finding that ascorbate promotes a decrease in cell surface levels of the neuronal glutamate transporter excitatory amino acid transporter 3 in retinal neuronal cultures. Interestingly, vitamin C is prone to increase the activity of NMDA receptors but also promotes a decrease in glutamate‐stimulated [3H] MK 801 binding and decreases cell membrane content of NMDA receptor glutamate ionotropic receptor subunit 1 (GluN1) subunits. Both compounds were also able to increase cAMP response element‐binding protein phosphorylation in neuronal nuclei in a glutamate receptor and calcium/calmodulin kinase‐dependent manner. Moreover, the effect of ascorbate is not blocked by sulfinpyrazone and then does not depend on its uptake by retinal cells. Overall, these data indicate a novel molecular and functional target for vitamin C impacting on glutamate signaling in retinal neurons.

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144.
Discrete choice, coupled with social influence, plays a significant role in evolutionary studies of human fertility, as investigators explore how and why reproductive decisions are made. We have previously proposed that the relative magnitude of social influence can be compared against the transparency of pay-off, also known as the transparency of a decision, through a heuristic diagram that maps decision-making along two axes. The horizontal axis represents the degree to which an agent makes a decision individually versus one that is socially influenced, and the vertical axis represents the degree to which there is transparency in the pay-offs and risks associated with the decision the agent makes. Having previously parametrized the functions that underlie the diagram, we detail here how our estimation methods can be applied to real-world datasets concerning sexual health and contraception.  相似文献   
145.
Little is known of the epidemiology of toxoplasmosis in Minnesota. Here, we evaluated Toxoplasma gondii infection in 50 wild bobcats (Lynx rufus) and 75 other animals on/near 10 cattle farms. Antibodies to T. gondii were assayed in serum samples or tissue fluids by the modified agglutination test (MAT, cut‐off 1:25). Twenty nine of 50 bobcats and 15 of 41 wildlife trapped on the vicinity of 10 farms and nine of 16 adult domestic cats (Felis catus) and six of 14 domestic dogs resident on farms were seropositive. Toxoplasma gondii oocysts were not found in feces of any felid. Tissues of all seropositive wild animals trapped on the farm were bioassayed in mice and viable T. gondii was isolated from two badgers (Taxidea taxus), two raccoons (Procyon lotor), one coyote (Canis latrans), and one opossum (Didelphis virginiana). All six T. gondii isolates were further propagated in cell culture. Multi‐locus PCR‐RFLP genotyping using 10 markers (SAG1, SAG2 (5′‐3′SAG2, and alt.SAG2), SAG3, BTUB, GRA6, c22‐8, c29‐2, L358, PK1, and Apico), and DNA from cell culture derived tachyzoites revealed three genotypes; #5 ToxoDataBase (1 coyote, 1 raccoon), #1 (1 badger, 1 raccoon, 1 opossum), and #2 (1 badger). This is the first report of T. gondii prevalence in domestic cats and in bobcats from Minnesota, and the first isolation of viable T. gondii from badger.  相似文献   
146.
Vegetation structure can often determine insect herbivore fauna in forests, but this mechanism has been demonstrated in seasonally dry tropical forests (SDTFs) only at small spatial scales. In this study we evaluated the effects of the geographical location of SDTFs and vegetation structure on insect herbivore communities (leaf-chewing and sap-sucking guilds) in three Brazilian ecoregions (Cerrado, Cerrado/Caatinga transition, and Caatinga). We tested the following predictions: (1) insect herbivore species composition, richness, abundance and beta diversity differ among forests in different ecoregions; (2) insect richness, abundance and beta diversity are positively related to tree richness and density; (3) spatial turnover of species is the primary mechanism that generates herbivorous insect β-diversity in different ecoregions, and is positively influenced by tree richness. The composition, richness, and abundance of herbivorous insects differed over SDFs along the gradient of Cerrado and Caatinga. Both herbivore guilds responded positively to tree richness. Tree density only determined the richness and abundance of sap-sucking herbivores. Insect β-diversity was similar among Cerrado and transition areas, but lower in Caatinga itself; β-diversity was also positively affected by tree richness. Species turnover, as opposed to nestedness, was the main mechanism generating β-diversity, but itself was not related to tree richness. We demonstrate in this study the importance of landscape diversity and availability of local resources for herbivorous insect communities, and we emphasize the importance of SDTF conservation in different ecoregions as a result of species turnover.  相似文献   
147.
A recent study on the pituitary of the sturgeon, Acipenser transmontanus, resulted in the cloning of a cDNA that codes for the prohormone, proopiomelanocortin (POMC). This cDNA is designated sturgeon POMC A. Subsequent analysis of the sturgeon pituitary uncovered a second distinct POMC cDNA (sturgeon POMC B). In both sturgeon POMC cDNAs the open reading frame is 795 nucleotides in length. However, the two sturgeon POMC cDNAs differ at 26 amino acid positions in the opening frame. In addition, the 2 forms of POMC differ at 45 nucleotide positions within the open reading frame. The number and types of point mutations are compared in the 2 sturgeons POMC cDNAs, and the origin of the two POMC genes is discussed.  相似文献   
148.
Micritization is an early diagenetic process that gradually alters primary carbonate sediment grains through cycles of dissolution and reprecipitation of microcrystalline calcite (micrite). Typically observed in modern shallow marine environments, micritic textures have been recognized as a vital component of storage and flow in hydrocarbon reservoirs, attracting scientific and economic interests. Due to their endolithic activity and the ability to promote nucleation and reprecipitation of carbonate crystals, microorganisms have progressively been shown to be key players in micritization, placing this process at the boundary between the geological and biological realms. However, published research is mainly based on geological and geochemical perspectives, overlooking the biological and ecological complexity of microbial communities of micritized sediments. In this paper, we summarize the state-of-the-art and research gaps in micritization from a microbial ecology perspective. Since a growing body of literature successfully applies in vitro and in situ ‘fishing’ strategies to unveil elusive microorganisms and expand our knowledge of microbial diversity, we encourage their application to the study of micritization. By employing these strategies in micritization research, we advocate promoting an interdisciplinary approach/perspective to identify and understand the overlooked/neglected microbial players and key pathways governing this phenomenon and their ecology/dynamics, reshaping our comprehension of this process.  相似文献   
149.
Trichoderma spp. is a fungus with nematode control potential; however, its potential to control the root lesion nematode Pratylenchus brachyurus remains poorly studied. Thus, the aim of this study was to select Trichoderma spp. isolates and assess their ability to control P. brachyurus in soybean crops. Different experiments were conducted aiming at selecting isolates, assessing whether they were able to reduce nematode penetration in plants or cause mortality in vitro, and whether they were able to induce resistance in soybean, as well as at studying the possibility of using the selected isolates associated with resistance inducers (acibenzolar‐S‐methyl, Ecolife? and AgroMos?). The selection experiment found three isolates showing satisfactory results, namely GF422, GF425 and GF427; the GF362 isolate was assessed in the subsequent experiments. These four isolates reduced P. brachyurus penetration in soybean roots and promoted nematode mortality in vitro. Increased total protein and catalase activity were recorded, mainly in the 72‐hr assessments. Overall, the protein production was different between isolates. The best results were found in the combination between the GF362 isolate and the three resistance inducers, between GF427 and Ecolife?, between GF427 and AgroMos? and between GF422 and Ecolife?.  相似文献   
150.
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