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This study assessed new insecticidal activities of essential oils from Lippia sidoides and Croton species (Croton zehntneri, Croton nepetaefolius, Croton argyrophylloides, and Croton sonderianus) against Aedes aegypti mosquito. In addition, the acute toxicity upon mice was determined. All essential oils showed inhibition of egg hatching, with IC50 values ranging from 66.4 to 143.2 μg?mL?1, larvicidal activity with LC50 ranging from 25.5 to 94.6 μg?mL?1, and pupicidal action with PC50 ranging from 276.8 to over 500 μg?mL?1. Only L. sidoides, C. zehntneri, and C. argyrophylloides essential oils were able to inhibit the oviposition of female gravid mosquitoes with OD50 values of 35.3, 45.3, and 45.8 μg?mL?1, respectively. Oral acute toxicity in mice showed that C. sonderianus and C. argyrophylloides oils are nontoxic (LD50?>?6,000 mg.kg?1) while C. nepetaefolius, C. zehntneri, and L. sidoides oils are moderately toxic (LD50 3,840; 3,464, and 2,624 mg.kg?1, respectively). The results indicate that these oils are promising sources of bioactive compounds, showing low or no toxicity to mammals.  相似文献   
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Objectives:The purpose of this study was to evaluate the usefulness of Hounsfield unit (HU) assessment with multislice-CT in the differentiation of radicular cysts (RCs), dentigerous cysts (DCs) and odontogenic keratocysts (OKCs).Methods:In total, 307 odontogenic cysts (RCs, DCs and OKCs) were included in this study. Cysts with lesion diameter <10 mm, cysts with artefacts affecting measurement of HU values, cysts involving infection and recurrent cysts were regarded as exclusion criteria. Images were acquired in three different types of CT scanners: Aquilion ONE, Discovery CT750 HD and SOMATOM Definition Flash. Differences in HU values among scanners and among types of odontogenic cysts were assessed using one-way analysis of variance; multiple comparisons were performed post hoc, using the Tukey–Kramer honestly significant difference test.Results:In total, 164 cysts were analysed in this study (64 RCs, 57 DCs and 43 OKCs). Regardless of the type of lesion, the Aquilion ONE scanner demonstrated a significant difference in HU value, compared with the Discovery CT750 HD scanner. Regardless of CT scanner model, HU values significantly differed between DCs and OKCs (p < 0.0001), as well as between OKCs and RCs (p < 0.0001).Conclusions:HU values were found to vary among CT scanners and should always be associated with other lesion imaging features while interpreting and elaboration diagnostic hypothesis. Notably, the results suggested that OKCs might be able to be differentiated from DCs and RCs by using HU values.  相似文献   
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Background: Subjective radiographic classifications of alveolar bone have been proposed and correlated with implant insertion torque (IT). The present diagnostic study aims to identify quantitative bone features influencing IT and to use these findings to develop an objective radiographic classification for predicting IT. Methods: Demographics, panoramic radiographs (taken at the beginning of dental treatment), and cone‐beam computed tomographic scans (taken for implant surgical planning) of 25 patients receiving 31 implants were analyzed. Bone samples retrieved from implant sites were assessed with dual x‐ray absorptiometry, microcomputed tomography, and histology. Odds ratio, sensitivity, and specificity of all variables to predict high peak IT were assessed. Results: A ridge cortical thickness >0.75 mm and a normal appearance of the inferior mandibular cortex were the most sensitive variables for predicting high peak IT (87.5% and 75%, respectively). A classification based on the combination of both variables presented high sensitivity (90.9%) and specificity (100%) for predicting IT. Conclusions: Within the limitations of this study, the results suggest that it is possible to predict IT accurately based on radiographic findings of the patient. This could be useful in the treatment plan of immediate loading cases.  相似文献   
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T Yada  A Urano  T Hirano 《Endocrinology》1991,129(3):1183-1192
The trout pituitary continuously released a large amount of GH for over a week in serum-free culture, but PRL secretion declined by day 2 in culture. The total amount of GH released during the 8 days exceeded the initial content. The pituitary content of PRL remained unchanged after 8 days of culture. The number of weakly stained GH-immunoreactive (ir) cells was increased by day 4 in culture. The GH mRNA levels in individual cells as revealed by in situ hybridization were maintained at around the same level throughout culture. In contrast, the stainability of PRL-ir cells remained unchanged during culture, although the levels of PRL mRNA decreased by day 8. Electron microscopic immunocytochemistry showed a decrease in the numbers of secretory granules and dilation of rough endoplasmic reticulum in GH-ir cells. GH synthesis, measured by incorporated [3H]leucine after GH immunoprecipitation, was elevated 120% on day 8 over day 0. The dominant control of GH and PRL secretion in rainbow trout seems to be the converse of those seen in mammals; inhibition for GH and stimulation for PRL.  相似文献   
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