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911.
Warm feet promote the rapid onset of sleep. 总被引:5,自引:0,他引:5
912.
913.
Benthic macroinvertebrates from four habitat types (river channel, ephemeral side channel, river backwater, and seasonally inundated wetland) were examined from the Green River at the Ouray National Wildlife Refuge, Uintah County, UT, June-August 1991. For major taxa (Nematoda, Oligochaeta, Diptera: Ceratopogonidea, and Chironomidae) were quantified. Chuster analysis of densities showed that habitat types with comparable flow conditions were the most similar. Highest to lowest overall benthic invertebrate densities of the four habitats were as follows: ephemeral side channel, river backwater, seasonally inundated wetland, and river channel. Nematodes were the most abundant taxon in all habitat types and sample dates except the August sample of the river channel and river backwater and the July sample of the seasonally inundated wetland. 相似文献
914.
In Iowa, the northern grasshopper mouse ( Onychomys leucogaster ) previously was known only from the northwestern part of the state. Herein, we report records of O. leucogaster from the 1970s and 1980s that extend its distribution into west-central and southwestern Iowa. These records may represent dispersal movements into these parts of Iowa by southward movements from populations in northwestern Iowa or they may represent eastward movements of individuals from Nebraska prior to channelization of the Missouri River. 相似文献
915.
Following the suppression of renewal of rat taste cells by vinblastine sulphate, the preference for sucrose decreased markedly while the aversion to quinine did not change. The results suggest that the sensitivity of taste cells to sucrose decreases with their aging, but the sensitivity to quinine increases. 相似文献
916.
Grace W. C. Cheung Andrea Kokorovic Tony K. T. Lam 《Cellular and molecular life sciences : CMLS》2009,66(18):3023-3027
Upon the entry of nutrients into the small intestine, nutrient sensing mechanisms are activated to allow the body to adapt
appropriately to the incoming nutrients. To date, mounting evidence points to the existence of an upper intestinal lipid-induced
gut–brain neuronal axis to regulate energy homeostasis. Moreover, a recent discovery has also revealed an upper intestinal
lipid-induced gut–brain–liver neuronal axis involved in the regulation of glucose homeostasis. In this mini-review, we will
focus on the mechanisms underlying the activation of these respective neuronal axes by upper intestinal lipids. 相似文献
917.
G S Jimenez F Bryntesson M I Torres-Arzayus A Priestley M Beeche S Saito K Sakaguchi E Appella P A Jeggo G E Taccioli G M Wahl M Hubank 《Nature》1999,400(6739):81-83
Damage to DNA in the cell activates the tumour-suppressor protein p53, and failure of this activation leads to genetic instability and a predisposition to cancer. It is therefore crucial to understand the signal transduction mechanisms that connect DNA damage with p53 activation. The enzyme known as DNA-dependent protein kinase (DNA-PK) has been proposed to be an essential activator of p53, but the evidence for its involvement in this pathway is controversial. We now show that the p53 response is fully functional in primary mouse embryonic fibroblasts lacking DNA-PK: irradiation-induced DNA damage in these defective fibroblasts induces a normal response of p53 accumulation, phosphorylation of a p53 serine residue at position 15, nuclear localization and binding to DNA of p53. The upregulation of p53-target genes and cell-cycle arrest also occur normally. The DNA-PK-deficient cell line SCGR11 contains a homozygous mutation in the DNA-binding domain of p53, which may explain the defective response by p53 reported in this line. Our results indicate that DNA-PK activity is not required for cells to mount a p53-dependent response to DNA damage. 相似文献
918.
919.
Mutations in a new gene encoding a thiamine transporter cause thiamine-responsive megaloblastic anaemia syndrome. 总被引:7,自引:0,他引:7
Thiamine-responsive megaloblastic anaemia syndrome (TRMA; MIM 249270) is an autosomal recessive disorder with features that include megaloblastic anaemia, mild thrombocytopenia and leucopenia, sensorineural deafness and diabetes mellitus. Treatment with pharmacologic doses of thiamine ameliorates the megaloblastic anaemia and diabetes mellitus. A defect in the plasma membrane transport of thiamine has been demonstrated in erythrocytes and cultured skin fibroblasts from TRMA patients. The gene causing TRMA was assigned to 1q23.2-q23.3 by linkage analysis. Here we report the cloning of a new gene, SLC19A2, identified from high-through-put genomic sequences due to homology with SLC19A1, encoding reduced folate carrier 1 (refs 8-10). We cloned the entire coding region by screening a human fetal brain cDNA library. SLC19A2 encodes a protein (of 497 aa) predicted to have 12 transmembrane domains. We identified 2 frameshift mutations in exon 2. a 1-bp insertion and a 2-bp deletion, among four Iranian families with TRMA. The sequence homology and predicted structure of SLC19A2, as well as its role in TRMA, suggest that its gene product is a thiamine carrier, the first to be identified in complex eukaryotes. 相似文献
920.