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To investigate dental development in patients treated with a hematopoietic stem cell transplantation (HSCT), 42 children and young adults who were under 12 years old at time of HSCT were examined for dental agenesis, microdontia, and root-to-crown ratio. Conditioning regimens were total body irradiation (TBI) based in 12 patients, busulfan based in 21 patients, and 9 patients had other chemotherapeutic agents. Sixteen patients were <3 years old, 9 patients were 3 to 6 years old, and 17 patients were 6 to 12 years old at HSCT. Prevalence of agenesis and microdontia of at least 1 permanent tooth were, respectively, 51.3% and 46.2% in the study population, and 76.3% had an aberrant root-to-crown ratio. All these results were highly different from the prevalence in the healthy population. Patients treated before the age of 3 years had more microdontia (76.9%) and agenesis (92.3%) compared with patients treated at an older age. In the subgroup of patients treated after 6 years, there was more microdontia when treated with busulfan (50%) compared with treatment with TBI (0%) (P?=?.044). Patients treated with HSCT had many disturbances in dental development. Age at HSCT and possibly also the conditioning regimen used had an effect on their type and prevalence. Dental follow-up should be incorporated in the multidisciplinary follow-up program of these patients.  相似文献   
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Virus Genes - Typically associated with fungal species, members of the viral family Totiviridae have recently been shown to be associated with plants, including important crop species, such as...  相似文献   
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Parasitology Research - Integrative taxonomy uses several sources of information to establish more robust species delimitation criteria. In this study, we followed that approach to describe two new...  相似文献   
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The genus Rhabdochona includes more than 100 species infecting freshwater fishes in all zoogeographical regions of the world. In Mexico, 12 nominal species of Rhabdochona have been recorded. Of these, Rhabdochona ictaluri was originally described as a parasite of endemic catfishes of the family Ictaluridae; however, the species was later considered on morphological grounds as a junior synonym of Rhabdochona kidderi. In this study, newly sampled specimens of R. ictaluri were obtained from the type host and type locality and were used to perform a detailed morphological analysis and molecular phylogenetic inferences through one mitochondrial and two nuclear genes; data were used in an integrative taxonomy context to test the taxonomic status of R. ictaluri. This approach proved to be very useful to confirm the validity of this species, and robust species limits were established between these two putative species considering morphology, molecular data, host association, and biogeography.

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