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11.
The study of the primate microbiome is critical in understanding the role of the microbial community in the host organism. To be able to isolate the main factors responsible for the differences observed in microbiomes within and between individuals, confounding factors due to technical variations need to be removed. To determine whether alterations due to preservatives outweigh differences due to factors such as host population, host species, body site, and habitat, we tested three methods (no preservative, 96% ethanol, and RNAlater) for preserving wild chimpanzee (fecal), wild lemur (fecal), wild vervet monkey (rectal, oral, nasal, otic, vaginal, and penile), and captive vervet monkey (rectal) samples. All samples were stored below ? 20°C (short term) at the end of the field day and then at ? 80°C until DNA extraction. Using 16S rRNA gene sequencing, we show a significant preservative effect on microbiota composition and diversity. Samples stored in ethanol and RNAlater appear to be less different compared with samples not stored in any preservative (none). Our differential analysis revealed significantly higher amounts of Enterococcaceae and Family XI in no preservative samples, Prevotellaceae and Spirochaetaceae in ethanol and RNAlater preserved samples, Oligosphaeraceae in ethanol‐preserved samples, and Defluviitaleaceae in RNAlater preserved samples. While these preservative effects on the microbiome are not large enough to remove or outweigh the differences arising from biological factors (e.g., host species, body site, and habitat differences) they may promote misleading interpretations if they have large enough effect sizes compared to the biological factors (e.g., host population).  相似文献   
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The ovaries of the largemouth bass Micropterus salmoides, an alien and invasive species in South Africa, contain a germinal epithelium which consists of germline and somatic cells, as well as previtellogenic and late vitellogenic ovarian follicles. The ovarian follicle consists of an oocyte surrounded by follicular cells and a basal lamina; thecal cells adjacent to this lamina are covered by an extracellular matrix. In this article, we describe the Balbiani body and the polarization and ultrastructure of the cytoplasm (ooplasm) in previtellogenic oocytes. The nucleoplasm in all examined oocytes contains lampbrush chromosomes, nuclear bodies and several nucleoli near the nuclear envelope. The ultrastructure of the nucleoli is described. Numerous nuage aggregations are present in the perinuclear cytoplasm in germline cells as well as in the ooplasm. Possible roles of these aggregations are discussed. The ooplasm contains the Balbiani body, which defines the future vegetal region in early previtellogenic oocytes. It is comprised of nuage aggregations, rough endoplasmic reticulum, Golgi apparatus, mitochondria, complexes of mitochondria with nuage-like material, and lysosome-like organelles. In mid-previtellogenic oocytes, the Balbiani body surrounds the nucleus and later disperses in the ooplasm. The lysosome-like organelles fuse and transform into vesicles containing material which is highly electron dense. As a result of the fusion of the vesicles of Golgi and rough endoplasmic reticulum, the cortical alveoli arise and distribute uniformly throughout the ooplasm of late previtellogenic oocytes. During this stage, the deposition of the eggshell (zona radiata) begins. The eggshell is penetrated by canals containing microvilli and consists of the following: the internal and the external egg envelope. In the external envelope three sublayers can be distinguished.  相似文献   
14.
Phylogenetic relationships, evolutionary history and systematics of tapeworms of the family Catenotaeniidae were studied using nucleotide sequences of the partial 28S nuclear rDNA (ca. 1,500 bp) and mitochondrial 12S–16S DNA (ca. 820 bp) genes. The tapeworm material consists of 29 species, including type species of the genera Catenotaenia Janicki, 1904, Catenotaenioides Haukisalmi, Hardman and Henttonen, 2010, Pseudocatenotaenia Tenora, Mas‐Coma, Murai and Feliu, 1980, Skrjabinotaenia Akhumyan, 1946, Meggittina Lynsdale, 1953, and Hemicatenotaenia Tenora, 1977. The basal phylogenetic structure of the Catenotaeniidae remains unresolved, but it is shown that most of the catenotaeniids in Eurasia and Africa comprise a large clade represented by species of Catenotaenia, Catenotaenioides, Skrjabinotaenia and Meggittina, parasitizing murid, cricetid, nesomyid and sciurid rodents. The results suggest that the divergence and early radiation of this clade have occurred in murid rodents (represented by Apodemus spp. and Mus musculus in the present material) in western Eurasia, followed by colonization of Africa, most likely independently of the colonization of their murid hosts between these continents. There is very little evidence of cophylogeny between hosts and parasites, suggesting that host transfers have played a major role in the divergence of catenotaeniids. In Africa, catenotaeniids have radiated in other murid and nesomyid rodents, and later colonized Madagascar and recolonized Eurasia. The results also show that the subfamily Skrjabinotaeniinae (including Skrjabinotaenia and Meggittina) is monophyletic, but the Catenotaeniinae (including Catenotaenia, Catenotaenioides, Pseudocatenotaenia and Hemicatenotaenia) is clearly non‐monophyletic. In addition, the genera Catenotaenia and Skrjabinotaenia were both found to be non‐monophyletic. Based on the phylogenetic and morphological evidence, several taxonomical changes, mainly new combinations, are proposed. Overall, the present results suggest that the family Catenotaeniidae is in need of major systematic revision.  相似文献   
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