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41.
Productive infection and cell-free transmission of human T-cell leukemia virus in a nonlymphoid cell line 总被引:34,自引:0,他引:34
P Clapham K Nagy R Cheingsong-Popov M Exley R A Weiss 《Science (New York, N.Y.)》1983,222(4628):1125-1127
Human T-cell leukemia virus (HTLV), American PL isolate, was transmitted by cocultivation and by cell-free filtrates to a nonlymphoid human osteogenic sarcoma (HOS) cell line, designated HOS/PL, but not to nine other lines bearing receptors for HTLV. HOS and HOS/PL cells are not dependent on interleukin-2 and do not express interleukin-2 receptors that are recognized by anti-Tac monoclonal antibody. HTLV released by the Japanese MT2 cell line was also transmitted to HOS cells. The infected HOS cells release substantial titers of progeny HTLV which is antigenically indistinguishable from parental virus and is able to transform T cells. 相似文献
42.
Immunohistochemistry of adenosine deaminase: implications for adenosine neurotransmission 总被引:11,自引:0,他引:11
Immunohistochemical analysis of adenosine deaminase in rat brain revealed an extensive plexus of adenosine deaminase-containing neurons in the basal hypothalamus. These neurons converged on and were most numerous in three major centers, namely, the tuberal, caudal, and postmammillary caudal magnocellular nuclei. Most other brain regions were devoid of cells containing adenosine deaminase. Some adenosine deaminase-containing neurons were retrogradely labeled with the fluorescent dye fast blue when the dye was injected into the frontal cortex and striatum. Specific populations of neurons having high levels of adenosine deaminase may release adenosine as a neurotransmitter. 相似文献
43.
Nagy AF Cravens TE Chen RH Taylor HA Brace LH Brinton HC 《Science (New York, N.Y.)》1979,205(4401):107-109
Datafrom the Pioneer Venus ion mass spectrometers are compared with model calculations of the ion density distributions appropriate for daytime conditions. The model assumes diffusive equilibrium upper boundary conditions for the major ions (O(2)(+), O(+), CO(2)(+), He(+), and H(+)); the agreement between the calculated and measured gross behavior of these ions is reasonably good except for H(+), which may be influenced strongly by convective transport processes. The distributions of five minor ions (C(+), N(+), NO(+), CO(+), and N(2)(+)) are also calculated for the chemically controlled region ( less, similar 200 kilometers); the agreements are, in general, poor, an indication that our present understanding of the Venus minor ion chemistry is still incomplete. 相似文献
44.
Abelson JF Kwan KY O'Roak BJ Baek DY Stillman AA Morgan TM Mathews CA Pauls DL Rasin MR Gunel M Davis NR Ercan-Sencicek AG Guez DH Spertus JA Leckman JF Dure LS Kurlan R Singer HS Gilbert DL Farhi A Louvi A Lifton RP Sestan N State MW 《Science (New York, N.Y.)》2005,310(5746):317-320
Tourette's syndrome (TS) is a genetically influenced developmental neuropsychiatric disorder characterized by chronic vocal and motor tics. We studied Slit and Trk-like 1 (SLITRK1) as a candidate gene on chromosome 13q31.1 because of its proximity to a de novo chromosomal inversion in a child with TS. Among 174 unrelated probands, we identified a frameshift mutation and two independent occurrences of the identical variant in the binding site for microRNA hsa-miR-189. These variants were absent from 3600 control chromosomes. SLITRK1 mRNA and hsa-miR-189 showed an overlapping expression pattern in brain regions previously implicated in TS. Wild-type SLITRK1, but not the frameshift mutant, enhanced dendritic growth in primary neuronal cultures. Collectively, these findings support the association of rare SLITRK1 sequence variants with TS. 相似文献
45.
Terracciano A Abdel-Khalek AM Adám N Adamovová L Ahn CK Ahn HN Alansari BM Alcalay L Allik J Angleitner A Avia MD Ayearst LE Barbaranelli C Beer A Borg-Cunen MA Bratko D Brunner-Sciarra M Budzinski L Camart N Dahourou D De Fruyt F de Lima MP del Pilar GE Diener E Falzon R Fernando K Ficková E Fischer R Flores-Mendoza C Ghayur MA Gülgöz S Hagberg B Halberstadt J Halim MS Hrebícková M Humrichouse J Jensen HH Jocic DD Jónsson FH Khoury B Klinkosz W Knezević G Lauri MA Leibovich N Martin TA 《Science (New York, N.Y.)》2005,310(5745):96-100
Most people hold beliefs about personality characteristics typical of members of their own and others' cultures. These perceptions of national character may be generalizations from personal experience, stereotypes with a "kernel of truth," or inaccurate stereotypes. We obtained national character ratings of 3989 people from 49 cultures and compared them with the average personality scores of culture members assessed by observer ratings and self-reports. National character ratings were reliable but did not converge with assessed traits. Perceptions of national character thus appear to be unfounded stereotypes that may serve the function of maintaining a national identity. 相似文献
46.
Gaschen B Taylor J Yusim K Foley B Gao F Lang D Novitsky V Haynes B Hahn BH Bhattacharya T Korber B 《Science (New York, N.Y.)》2002,296(5577):2354-2360
Globally, human immunodeficiency virus-type 1 (HIV-1) is extraordinarily variable, and this diversity poses a major obstacle to AIDS vaccine development. Currently, candidate vaccines are derived from isolates, with the hope that they will be sufficiently cross-reactive to protect against circulating viruses. This may be overly optimistic, however, given that HIV-1 envelope proteins can differ in more than 30% of their amino acids. To contend with the diversity, country-specific vaccines are being considered, but evolutionary relationships may be more useful than regional considerations. Consensus or ancestor sequences could be used in vaccine design to minimize the genetic differences between vaccine strains and contemporary isolates, effectively reducing the extent of diversity by half. 相似文献
47.
Plant circadian clocks increase photosynthesis, growth, survival, and competitive advantage 总被引:3,自引:0,他引:3
Dodd AN Salathia N Hall A Kévei E Tóth R Nagy F Hibberd JM Millar AJ Webb AA 《Science (New York, N.Y.)》2005,309(5734):630-633
Circadian clocks are believed to confer an advantage to plants, but the nature of that advantage has been unknown. We show that a substantial photosynthetic advantage is conferred by correct matching of the circadian clock period with that of the external light-dark cycle. In wild type and in long- and short-circadian period mutants of Arabidopsis thaliana, plants with a clock period matched to the environment contain more chlorophyll, fix more carbon, grow faster, and survive better than plants with circadian periods differing from their environment. This explains why plants gain advantage from circadian control. 相似文献
48.
The main tasks for climate controllers in potato bulk stores are to keep the storage climate in an appropriate condition for quality conservation. To avoid extra energy costs by using cooling systems the internal climate of potato bulk stores is controlled with outdoor air. A conventionally designed controller is difficult to adapt for an optimal climate control to reduce quality loss. However, a controller designed with fuzzy logic is found as advantageous for adapting control parameters to improve the control process. A test stand is built to ventilate and to control two samples of potato bulks simultaneously with the same outdoor weather conditions for comparisons. Several experiments were carried out to compare climate controllers with different control algorithms, i.e. conventional to a different conventional and conventional to fuzzy. 相似文献
49.
He H Liyanarachchi S Akagi K Nagy R Li J Dietrich RC Li W Sebastian N Wen B Xin B Singh J Yan P Alder H Haan E Wieczorek D Albrecht B Puffenberger E Wang H Westman JA Padgett RA Symer DE de la Chapelle A 《Science (New York, N.Y.)》2011,332(6026):238-240
Small nuclear RNAs (snRNAs) are essential factors in messenger RNA splicing. By means of homozygosity mapping and deep sequencing, we show that a gene encoding U4atac snRNA, a component of the minor U12-dependent spliceosome, is mutated in individuals with microcephalic osteodysplastic primordial dwarfism type I (MOPD I), a severe developmental disorder characterized by extreme intrauterine growth retardation and multiple organ abnormalities. Functional assays showed that mutations (30G>A, 51G>A, 55G>A, and 111G>A) associated with MOPD I cause defective U12-dependent splicing. Endogenous U12-dependent but not U2-dependent introns were found to be poorly spliced in MOPD I patient fibroblast cells. The introduction of wild-type U4atac snRNA into MOPD I cells enhanced U12-dependent splicing. These results illustrate the critical role of minor intron splicing in human development. 相似文献
50.
Production of chitinases with Trichoderma harzianun isolates using solid substrate fermentation 下载免费PDF全文
Over forty Trichoderma harzianum isolates have been screened in solid substrate fermentation (SSF)for chitinase production. Strains were isolated from Asian soil and tree bark samples. Identification was performed in Canada and Austria by classical and molecular taxonomical methods.…… 相似文献