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ObjectiveTo describe the seminiferous epithelium cycle (SEC) by tubular morphology method, and the acrosomal development of individualizing spermatids, and to explore the distinction of the stages between two generations of spermatids.MethodsTesticular fragments were fixed in Karnovsky, embedded in glycol methacrylate and examined under light microscopy and transmission electron microscopy. Sections in 3 μm thickness were stained with toluidine blue for the characterization of the stages of the SEC by the tubular morphology method, or submitted to the PAS reaction for the visualization of the acrosomal formation. Additional details on the acrosomal formation were observed under transmission electron microscopy.ResultsThrough the eight stages described by tubular morphology method, 10 steps of acrosomal formation were observed in the spermatid development, called acrosomal steps. As the spermatids were produced in stage V of the tubular morphology method, it was at this stage from which began the steps of acrosomal development.ConclusionsWe propose association of the acrosomal steps for the first time, with the different stages by tubular morphology method. This method presents an alternative to the existent Methods, allowing interspecific comparisons of the SEC, not only among different species of bats, but also among the other mammals.  相似文献   
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This report describes a rare case of coexistence of benign phyllodes tumor, which measured 9 cm in the right breast, and invasive ductal carcinoma of 6 cm in the left breast, synchronous and independent, in a 66-year-old patient. The patient underwent a bilateral mastectomy due to the size of both lesions. Such situations are rare and usually refer to the occurrence of ductal or lobular carcinoma in situ when associated with malignant phyllodes tumors, and more often in ipsilateral breast or intra-lesional.  相似文献   
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ObjectiveTo examine the influence of a preventative training program (PTP) on sagittal plane kinematics during different landing tasks and vertical jump height (VJH) in males.DesignSix weeks prospective exercise intervention.ParticipantsFifteen male volleyball athletes (13 ± 0.7 years, 1.70 ± 0.12 m, 60 ± 12 kg).InterventionsPTP consisting of plyometric, balance and core stability exercises three times per week for six weeks. Bilateral vertical jumps with double leg (DL) and single leg (SL) landings were performed to measure the effects of training.Main outcome measurementsKinematics of the knee and hip before and after training and VJH attained during both tasks after training. The hypothesis was that the PTP would produce improvements in VJH, but would not generate great changes in biomechanical behavior.ResultsThe only change identified for the SL was the longest duration of landing, which represents the time spent from initial ground contact to maximum knee flexion, after training, while increased angular displacement of the knee was observed during DL. The training did not significantly alter the VJH in either the SL (difference: 2.7 cm) or the DL conditions (difference: 3.5 cm).ConclusionsDespite the PTP’s effectiveness in inducing some changes in kinematics, the changes were specific for each task, which highlights the importance of the specificity and individuality in selecting prevention injury exercises. Despite the absence of significant increases in the VJH, the absolute differences after training showed increases corroborating with the findings of statistically powerful studies that compared the results with control groups. The results suggest that short-term PTPs in low risk young male volleyball athletes may enhance performance and induce changes in some kinematic parameters.  相似文献   
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American cutaneous leishmaniasis (ACL) caused by Leishmania (Viannia) braziliensis is a neglected disease of humans in the New World that may also cause irreversible skin and eventually mucocutaneous lesions. This parasite can also infect dogs and represents a diagnostic challenge for veterinarians. Methods currently available for the diagnosis of ACL have a low sensitivity and may be time-consuming, representing a limit for treatment expedition of ACL. Quantitative real time PCR assays (qPCR) for the detection of L. (V.) braziliensis in canine blood samples were developed herein, and the detection limit and specificity of different molecular targets (kDNA and rDNA) evaluated. Of the protocols assessed, two qPCR assays, one targeting the kDNA and other the SSU rDNA of L. (V.) braziliensis, performed better, with detection limits of 100 fg and 10 pg, respectively. These assays were also used to test skin samples from humans with suspected ACL. The results indicate that the qPCR protocols developed represent an advance for the diagnosis of ACL in dogs and humans from this region, and provide a rapid and non-invasive diagnosis of the infection by L. (V.) braziliensis. Considering the quantitative nature of the assays, they will also be useful for monitoring treatment efficacy and preventing relapses in human patients in Brazil, although further studies are needed to critically evaluate the specificity of the qPCRs for their capacity to distinguish different Leishmania species and subspecies (represented by zymodemes) in other countries. Finally, molecular assays established may represent new tools for future basic and applied research focused on species identification, host–parasite associations, and infection dynamics in host and vector populations.  相似文献   
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