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141.
MB Malipatil 《Australian Journal of Entomology》2005,44(2):122-131
Abstract Two new species of Nysius Dallas, N. orarius sp. n. and N. tasmaniensis sp. n. are described from New South Wales and Tasmania (Australia), respectively. A new monotypic genus, Reticulatonysius , with type-species R. queenslandensis sp. n. is described from Queensland, and its systematic relationship with other orsilline genera is discussed. 相似文献
142.
Intracellular ionic strength regulates the volume sensitivity of a swelling-activated anion channel 总被引:4,自引:0,他引:4
Cannon Carolyn L.; Basavappa Srisaila; Strange Kevin 《American journal of physiology. Cell physiology》1998,275(2):C416
Cell swellingactivates an outwardly rectifying anion channel termed VSOAC(volume-sensitive organic osmolyte/anion channel). Regulation of VSOACby intracellular electrolytes was characterized in Chinese hamsterovary cells by whole cell patch clamp. Elevation of intracellular CsClconcentration from 40 to 180 mM resulted in a concentration-dependentdecrease in channel activation. Activation of VSOAC was insensitive tothe salt gradient across the plasma membrane, the intracellularconcentration of specific anions or cations, and the totalintracellular concentration of cations, anions, or electrolytes.Comparison of cells dialyzed with either CsCl orNa2SO4solutions demonstrated directly that VSOAC activation is modulated byintracellular ionic strength(µi). The relative cell volumeat which VSOAC current activation was triggered, termed the channelvolume set point, decreased with decreasing ionic strength. Atµi = 0.04, VSOAC activationoccurred spontaneously in shrunken cells. The rate of VSOAC activationwas nearly 50-fold higher in cells withµi = 0.04 vs. those withµi = 0.18. We propose thatµi modulates the volume sensorresponsible for channel activation. 相似文献
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144.
Li F Bielke W Ke G Andres AC Jaggi R Saurer S Friis RR Niemann H Bemis L Geske FJ Strange R 《Cell death and differentiation》1995,2(2):113-122
Although apoptosis is important in determining cell fate and maintaining tissue homeostasis, the initiation and control of apoptotic cell death in epithelium is not well understood. Post-lactationai involution of the mammary gland provides both an important developmental process and a normal physiological setting for studying apoptosis of epithelium. We used a differential screening strategy, based on previous studies correlating morphology with gene expression and nucleic acid integrity during mammary gland involution, to isolate genes involved in the regulation and execution of apoptotic cell death in regressing mammary epithelium. This screening strategy yielded a large number of genes the expression of which is significantly altered during mammary gland involution. These include genes associated with cell death processes, tissue remodelling and mesenchymal differentiation. In addition, a number of novel genes have been isolated. We have used Northern analysis and in situ hybridisation to study the expression of a selection of these putative death-associated genes during post-lactational mouse mammary gland involution. 相似文献
145.
Johanna W. Baars Johanna C. M. Fonk Riekeld J. Scheper B. Mary E. von Blomberg-van der Flier Herman Bril M.D. Paul v. d. Valk Herbert M. Pinedo John Wagstaff MD MB ChB MRCP 《Biotherapy》1992,4(4):289-297
Tumour infiltrating lymphocytes (TIL) were isolated and expanded from biopsy samples of 4 patients with metastatic melanoma. The patients were treated with autologous expanded TIL and continuous or bolus infusion of Interleukin 2 (IL-2) at a dose of 18 × 106 International Units/m2/day for 5 days starting 36–48 hours after administration of cyclophosphamide at a dose of 1 g/m2. The number of TIL infused ranged from 1010 to 5,56 × 1010 cells. Two patients had stable disease (SD) lasting for 2 1/2 and 4 months respectively and they died 24 and 13 months after therapy. One patient died during therapy due to a pseudomonas septicaemia and another patient developed progressive disease (PD). He died 3 months after the start of therapy. The side effects were substantial but most of them were reversible upon cessation of the treatment.The majority of the expanded TIL of all patients were of the CD8+ phenotype. Cutaneous metastases from two patients, removed after treatment with IL-2 and TIL, showed moderate lymphocytic infiltration also mainly of CD8+ T cells.The treatment with IL-2 and TIL is feasible, but further investigations should continue in an attempt to improve the efficacy of the therapy, to reduce toxicity and to diminish the costs and labour of the culture methods. 相似文献
146.
Muscarinic Acetylcholine Receptors in Neuroblastoma Cells: Lack of Effect of Veratrum Alkaloids on Receptor Number 总被引:2,自引:2,他引:0
The effect of compounds that activate sodium channels on the number of muscarinic acetylcholine receptors in neuroblastoma NIE 115 cells has been investigated. The cells were used in electrically unexcitable ("control" cells) and excitable ("differentiated" cells) states. Although receptor assays using a single concentration of the radioligand [3H]scopolamine methyl chloride indicated a loss of receptors after a 6-h incubation of cells with veratrine, no true loss of receptors was seen with any of the compounds tested (veratridine, veratrine, aconitine) when full saturation analyses were performed in either control or differentiated cells. The apparent receptor loss seen with veratrine was due to a muscarinic receptor-active component of veratrine (not veratridine) occluded by the cells and released into the binding assays upon cell breakage. Veratridine and aconitine have a very low affinity for muscarinic acetylcholine receptors, and the binding of carbamoylcholine to the receptors is unaffected by tetrodotoxin, so that there is no evidence in this system for interaction between muscarinic receptors and sodium channels. 相似文献
147.
Constancea nevinii (A. Gray) B.G. Baldwin (Compositae: Heliantheae: Baeriinae) is described and illustrated. The distribution of the species in, and a glimpse at the history and endemic flora of, the California Channel Islands (also known as the Santa Barbara Islands), together with the conservation threats posed by feral goats, is outlined. The historically variable Conservation Status is commented on, although the species is no longer considered under threat of extinction. The position of this monotypic genus in the Heliantheae is commented on. Cultivation, propagation, and availability notes are provided. The species is rarely cultivated in the United Kingdom, but clearly widely so in the western States along the Californian coast. 相似文献
148.
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150.
K S Rogerson D Mitchell A Lawton R Ibbotson W Cotton R C Strange 《Biochemical and biophysical research communications》1984,122(1):407-412
The glutathione S-transferases of human platelets have been compared with those of erythrocytes. Although wide variations in activity were found, in individual subjects, the activity in these cell types was significantly correlated. The enzymes demonstrated similar isoelectric points and electrophoretic mobilities and it appears that the platelet enzyme is also a product of the GST3 locus. There was no correlation between platelet enzyme activity and plasma concentrations of retinol and cholesterol, but in men, the relationship between activity and carotene was significant. It is suggested that GST3 isoenzyme activity depends on vitamin A. 相似文献