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251.
Mouthpart and alimentary canal development was examined in Lysmata amboinensis larvae using scanning electron microscopy and histology. The gross morphological features of external mouthparts and internal digestive tract structures of larvae at different developmental stages indicate that ingestive and digestive capabilities are well developed from early on. With increasing age of the larvae the mouthpart appendages increased in size, the hepatopancreas in tubular density and the midgut in length. The density of setae and robustness of teeth and spines of individual structures increased. The most pronounced changes from early to late stage larvae involved formation of pores on the paragnaths and labrum, transformation of the mandibular spine‐like teeth to molar cusps, development of the filter press in the proventriculus and of infoldings in the previously straight hindgut. The results suggest that early stage L. amboinensis larvae may benefit from soft, perhaps gelatinous prey, whereas later stages are better equipped to handle larger, muscular or more fibrous foods. J. Morphol. 2011. © 2011 Wiley‐Liss, Inc. 相似文献
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Constantin S. Papadimitriou Stella N. Stephanaki-Nikou Vasiliki D. Malamou-Mitsi 《Virchows Archiv. B, Cell pathology including molecular pathology》1983,43(1):31-36
The immunoperoxidase technique after trypsinization was used on paraffin sections of 24 lymph nodes with reactive lymphadenitis and abundant nests of T-associated plasma cells. These cells were negative for all the markers investigated, which were: intracytoplasmic immunoglobulins (CIg), a1-antichymotrypsin(a1-ACT), a1-antitrypsin(a1-AT), lysozyme(Lz) and fibronectin. Other categories of cells were positive or negative depending on their type. The best markers for polymorphs proved to be a1-AT and Lz, and for monocytes and histiocytes a1-ACT and Lz. Sinus histiocytes in particular were much more constantly and strongly positive for a1-ACT than for Lz. Endothelial cells appeared almost always positive for a1-ACT and were also occasionally positive for a1-AT. Fibronectin was consistently positive in mast cells and sometimes positive in other cells, especially those of monohistiocytic origin. Our present findings are against a B-cell or monohistiocytic origin for T-associated plasma cells. 相似文献
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Hyun-jung Cho Vasiliki Staikopoulos Jason J. Ivanusic Ernest A. Jennings 《Cell and tissue research》2009,338(2):171-177
Hyperpolarization-activated cyclic nucleotide-gated (HCN) cation channels are active at resting membrane potential and thus
are likely to contribute to neuronal excitability. Four HCN channel subunits (HCN1–4) have previously been cloned. The aim
of the current study was to investigate the immunoreactivity of HCN4 channel protein in rat trigeminal (TG) and dorsal root
ganglion (DRG) sensory neurons. HCN4 was present in 9% of TG neurons and 4.7% of DRG neurons, it was distributed in a discrete
population of small-diameter neurons in the TG but was located in cells of all sizes in the DRG. Approximately two thirds
of HCN4-containing neurons in each ganglia were labelled with antisera raised against the 200-kDa neurofilament (NF200). The
remaining HCN4-containing neurons were NF200-negative, were not labelled with antisera raised against calcitonin-gene related
peptide (CGRP), and did not bind the isolectin B4 (IB4). HCN4-containing neurons made up more than half of the population
of small-diameter primary afferent neurons that did not contain either NF200 or CGRP or bind IB4 in both TG and DRG. This
population was not insignificant, comprising 5% of TG neurons and 2% of DRG neurons. 相似文献
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Manousos Makridakis Sarantis Gagos Andreas Petrolekas Maria G. Roubelakis Vasiliki Bitsika Konstantinos Stravodimos Kitty Pavlakis Nicholas P. Anagnou Jonathan Coleman Antonia Vlahou 《Proteomics》2009,9(2):287-298
Cell line models aid in understanding cancer aggressiveness. The aim of this study was the establishment of a metastatic variant (T24M) of the T24 bladder cancer cell line and its initial characterization at chromosomal and proteomic levels. T24M were spontaneously developed in mice from T24 cells, following cycles of subcutaneous injections and culture in vitro. Transwell migration assays and injections in mice revealed increased migration and tumorigenic properties of T24M compared to the T24 cells. Cytogenetic analysis demonstrated that T24M retained several karyotypic characteristics of the parental cells and also acquired novel chromosomal aberrations related to aggressive bladder cancer. Proteomic analysis of the T24 and T24M cells by 2‐DE and MS led to the generation of their 2‐DE proteomic map and revealed differences in multiple proteins. These include proteases of the lysosomal and proteasome degradation pathways, mitochondrial and cytoskeletal proteins. The 2‐DE findings were confirmed by immunoblotting of cell lysates and immunohistochemistry of bladder cancer tissue sections for cathepsin D and activity assays for proteasome. Collectively, our results suggest that the T24M cells reflect many known chromosomal and proteomic aberrations encountered in aggressive bladder cancers but also provide access to novel findings with potentially clinical applications. 相似文献