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排序方式: 共有235条查询结果,搜索用时 31 毫秒
1.
I D Craig D T Shum P Desrosiers C McLeod M S Lefcoe N A Paterson R J Finley B Woods R J Anderson 《Acta cytologica》1983,27(6):647-650
A case of choriocarcinoma metastatic to the lung following a previous hydatidiform mole is presented. It was possible to make definitive identification of trophoblastic elements on a needle aspiration biopsy using an immunoperoxidase staining technique, thus avoiding diagnostic thoracotomy prior to therapeutic intervention. A method of immunoperoxidase staining of previously fixed and Papanicolaou-stained needle aspiration biopsy specimens is also described, and other uses of the immunoperoxidase technique on needle biopsy specimens are discussed. 相似文献
2.
CK Bower J McGuire MA Daeschel 《Journal of industrial microbiology & biotechnology》1995,15(3):227-233
The efficacy of the antimicrobial peptide nisin was examined after adsorption to silica surfaces. Three protocols were used to evaluate nisin's activity against adhered cells ofListeria monocytogenes: bioassay usingPediococcus pentosaceous FBB 61-2 as the sensitive indicator strain; visualization and enumeration of cells by microscopic image analysis; and viability of adhered cells as determined by lodonitrotetrazolium violet uptake and crystallization. The activity of adsorbed nisin was highly dependent upon conditions of adsorption. The highest antimicrobial activity of adsorbed nisin occurred with high concentrations of nisin (1.0 mg ml–1) and brief contact times (1 h) on surfaces of low hydrophobicity. Sequential adsorption of a second protein (-lactoglobulin or bovine serum albumin) onto surfaces consistently resulted in decreased nisin activity. These data provide direction for the development of applications to limit microbial attachment on food contact surfaces through the use of adsorbed antimicrobial peptides. 相似文献
3.
Pine needle growth and fine structure after prolonged acid rain treatment in the subarctic 总被引:1,自引:0,他引:1
The growth and morphology of Scots pine needles were studied in a long-term acid rain experiment in the far north of Finnish Lapland. Pine trees 5 m tall of age 50–70 years were exposed, by spraying the foliage and soil from a height of 2 m, to either clean water (IC) or acidified water over the period 1985–1992, the acidification site being divided into sub-areas in which the precipitation contained two levels of either sulphuric (Sm, Sh) or nitric (Nm, Nh) acid, or both (SNm, SNh). The treatments with medium and high sulphate-S over eight consecutive years yielded a total sulphur deposition of 3·4 and 17·1 gm−2, respectively, and those with medium and high nitrate-N a total nitrogen deposition of 1·1 and 5·9 g m−2. Needles were collected for light and electron microscopy, growth measurements and morphometry. Growth in branch height had decreased by about 40% after 6 years of SNm or SNh treatment, and needle growth by 15% in the SNh trees as compared with the irrigated control trees (IC), although decreases were statistically significant only with respect to the non-irrigated control trees (DC). Growth of branches and needles was slightly better in the Nh treatment than in the IC group. The areas of the whole needle, the mesophyll and the phloem decreased in response to SNh treatment as compared with IC or DC, and a statistically significant decrease of about 30–40% was seen in the area of the xylem in comparison with DC. Cellular damage was observed following the acid treatments, especially with a high acid load. The damage was manifested in collapse of the cellular compartments, increases in lipid accumulations and swelling or disorganization of the protoplast. Increased vacuolization of the cytoplasm, plasmalemma irregularities and chilling-type damage to the mitochondria were also observed. 相似文献
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Wu LJ Ko SW Toyoda H Zhao MG Xu H Vadakkan KI Ren M Knifed E Shum F Quan J Zhang XH Zhuo M 《PloS one》2007,2(1):e167
GABAergic transmission in the amygdala modulates the expression of anxiety. Understanding the interplay between GABAergic transmission and excitatory circuits in the amygdala is, therefore, critical for understanding the neurobiological basis of anxiety. Here, we used a multi-disciplinary approach to demonstrate that GluR5-containing kainate receptors regulate local inhibitory circuits, modulate the excitatory transmission from the basolateral amygdala to the central amygdala, and control behavioral anxiety. Genetic deletion of GluR5 or local injection of a GluR5 antagonist into the basolateral amygdala increases anxiety-like behavior. Activation of GluR5 selectively depolarized inhibitory neurons, thereby increasing GABA release and contributing to tonic GABA current in the basolateral amygdala. The enhanced GABAergic transmission leads to reduced excitatory inputs in the central amygdala. Our results suggest that GluR5 is a key regulator of inhibitory circuits in the amygdala and highlight the potential use of GluR5-specific drugs in the treatment of pathological anxiety. 相似文献
8.
Residue 3 of β2-microglobulin affects binding of class I MHC molecules by the W6/32 antibody 总被引:4,自引:0,他引:4
Previous studies of class I MHC molecules have shown that the owl monkey (Aotus) possesses at least two variants of the β2-microglobulin (β2m) protein. These two variants have different isoelectric points, and exhibit differential reactivity with the monoclonal
antibody W6/32. We report cDNA sequences of the B2m gene, from W6/32-positive and W6/32-negative Aotus cell lines. The two β2m variants we identified exhibit a single amino acid difference at position three. An arginine residue at position 3 was correlated
with W6/32 reactivity, whereas histidine was associated with non-reactivity. W6/32 reactivity was conferred to a W6/32-negative
Aotus cell line when it was transfected with the B2m from the W6/32-positive cell line. Residue 3 of β2m is located at the surface of the class I molecule. It is also close to position 121 of the MHC class I heavy chain, which
has previously been shown to influence W6/32 antibody binding. We conclude that W6/32 binds a compact epitope on the class
I molecule that includes both residue 3 of β2m and residue 121 of the heavy chain. We examined the distribution of the two β2m motifs in a sample Aotus population using an allele-specific polymerase chain reaction assay. The pattern of β2m segregation we observed matches that which was defined previously by serology. Additionally, we identified laboratory-born
hybrid animals who possess both variants of β2m.
Received: 1 April 1998 / Received: 3 July 1998 相似文献
9.
Shum PW Peet NP Weintraub PM Le TB Zhao Z Barbone F Cashman B Tsay J Dwyer S Loos PC Powers EA Kropp K Wright PS Bitonti A Dumont J Borcherding DR 《Nucleosides, nucleotides & nucleic acids》2001,20(4-7):1067-1078
Cyclin-dependent kinases (CDKs) belong to a class of enzymes that control the ability of a cell to enter into and proceed through the cell division cycle. Using purine as a scaffold, we have synthesized a number of nanomolar inhibitors of CDK-2/cyclin E. In this report, the synthesis of a series of piperidine-substituted purine analogs will be presented, as well as some of their in vitro and in vivo biological effects. 相似文献
10.
Zhang JC Helmke BP Shum A Du K Yu WW Lu MM Davies PF Parmacek MS 《Mechanisms of development》2002,115(1-2):161-166
Cytoskeletal proteins play important roles in regulating cellular morphology, cytokinesis and intracellular signaling. In this report, we describe a developmentally regulated gene encoding a novel cell lineage-restricted cytoskeletal protein, designated SM22beta. SM22beta shares high-grade sequence identity with the smooth muscle cell (SMC)-specific protein, SM22alpha, the neuron-specific protein, NP25, and the Drosophila melanogaster flight muscle-specific protein, mp20. The mouse SM22beta cDNA encodes a 199-amino acid polypeptide that contains a single conserved calponin-like repeat domain. During mouse embryonic development, the SM22beta gene is expressed in a temporally and spatially regulated pattern in the tunica media of arteries and veins, endocardium and compact layer of the myocardium, bronchial epithelium and mesenchyme of the lung, gastrointestinal epithelium and cartilaginous primordia. During postnatal development, SM22beta is co-expressed with SM22alpha in arterial and venous SMCs. In addition, SM22beta is expressed at high levels in the bronchial epithelium and lung mesenchyme, gastrointestinal epithelial cells and in the cartilagenous and periosteal layer of bones. Three-dimensional deconvolution microscopic analyses of A7r5 SMCs revealed that SM22beta co-localizes with SM22alpha to cytoskeletal actin filaments. Taken together, these data demonstrate that SM22beta is a novel actin-associated protein with a unique cell lineage-restricted pattern of expression. 相似文献