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901.
Mycopathologia - A correction to this paper has been published: https://doi.org/10.1007/s11046-021-00559-9  相似文献   
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We studied tissue sections of freshly obtained full-term and premature human umbilical cords using polyclonal antibody to endothelin and immunocytochemistry. Endothelin immunoreactivity was detected in the cytoplasm of epithelial cells and primitive fibroblasts, but not in the endothelial cells of both full-term and premature umbilical cords. Immunoelectron microscopy using indirect immunogold staining technique localized endothelin immunoreactivity to the cytoplasm of the epithelial cells and fibroblasts but not confined to any particular structures. No endothelin immunoreactivity was detected in the nucleus or on the cell membrane. Pre-absorption tests with synthetic endothelin-1, -2, and -3 independently established that the immunoreactivity represented endothelin-1 and -2, but not -3. The presence of endothelin-1 and -2-like immunoreactive materials in epithelial cells and fibroblasts of human umbilical cord suggests a role of endothelin in parturition.  相似文献   
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The aim of this study was to investigate the relative growth and onset of morphological sexual maturity of the freshwater crab Sylviocarcinus pictus. Specimens were collected every month from October 2013 to September 2014, at night, on a stretch of the river Guaribas, Piauí, Brazil. Crabs were sexed and their carapace width (CW, independent variable), carapace length (CL), cheliped propodus length (PL) and height (PH), gonopod length (GL), and abdomen width (AW) (dependent variables) were measured. These measurements were related to characterise relative growth and possible sex differences. On average males were larger than females (p = 0.0001). Size at the onset of morphological sexual maturity was defined by relating CL vs. PL for males (30.82 mm) and CL vs. AW for females (28.63 mm). These are considered secondary sexual characters and reflect initial size at morphological sexual maturity with greater precision. The differential cheliped growth of males may be related to courting and disputes with other males, while the allometric growth of the abdomen of females indicates increased probability of reproductive success.  相似文献   
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The increase of tissue transparency through sequential optical immersion clearing treatments and treatment reversibility have high interest for clinical applications. To evaluate the clearing reversibility in a broad spectral range and the magnitude of the transparency created by a second treatment, the present study consisted on measuring the spectral collimated transmittance of lung tissues during a sequence of two treatments with electronic cigarette (e-cig) fluid, which was intercalated with an immersion in saline. The saline immersion clearly reverted the clearing effect in the lung tissue in the spectral range between 220 and 1000 nm. By a later application of a second treatment with the e-cig fluid, the magnitude of the optical clearing effect was observed to be about the double as the one observed in the first treatment, showing that the molecules of the optical clearing agent might have converted some bound water into mobile water during the first treatment.  相似文献   
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The African clawed frog Xenopus laevis has been introduced at several locations, including Mediterranean climate-type regions. In 2006, several individuals of this species were found inhabiting a stream at Oeiras, about 20 km W of Lisbon, Portugal. Although the place and time of introduction are not clearly identified, there are reasons to believe that this population may be the result of an almost 30-year-old introduction proceeding from research laboratories located nearby. Field surveys were conducted in 2007 and 2008 on the distribution and abundance of this species in the region. The species was found in two streams, about 5 km from each other. While being locally abundant, the adults of X. laevis are smaller than those from South Africa and California. In spite of an abundant production of eggs and tadpoles at one of the streams, no tadpoles were found in advanced developmental stages. Until now, most individuals were found in heavily urbanized areas that should constrain their ability to cross overland to other water bodies. An eradication program may be feasible, but the presence of adults on two streams indicates that the species may be expanding, in spite of the urban landscape.  相似文献   
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