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21.
The MAP kinase p38 has been implicated in cytokine signaling, and its inhibitors are potentially useful for the treatment of arthritis and osteoporosis. Novel small-molecule inhibitors of p38 kinase were derived from a combinatorial chemistry effort and exhibit activity in the nanomolar range. Very steep structure-activity relationships are observed within this class.  相似文献   
22.
Here we describe a fully automated, hands-free radioligand filtration binding assay for dopamine D3 receptors. Three separate instruments were linked in tandem to perform the following operations: The Genmate and Genesis were linked to perform liquid handling, incubation, and the scheduling operations, while an automated harvester was used to perform rapid filtration. To minimize carryover of compounds, disposable tips were used for diluting and dispensing the compounds. A custom-designed tip holder was used to handle loading and pipetting by the Genmate 96-well pipettor. The assay for 84 compounds with six concentrations that spans six logs can be completed within 4 h. The reproducibility of the individual data point (cv < 10% between duplicates) and Ki (cv < 20%) is superior to that determined by manual procedures. Ki values of various dopamine ligands determined by the hands-free procedure are similar to published values. This technology reduces hands-on time (at least 70%), minimizes exposure to radioligands (up to 95%), and improves the reproducibility of results. The technology is applicablefor high-throughput screening and rapid determination of structure-activity relationship of compounds for many other membrane-bound receptors.  相似文献   
23.

Background  

The genus Morus, known as mulberry, is a dioecious and cross-pollinating plant that is the sole food for the domesticated silkworm, Bombyx mori. Traditional methods using morphological traits for classification are largely unsuccessful in establishing the diversity and relationships among different mulberry species because of environmental influence on traits of interest. As a more robust alternative, PCR based marker assays including RAPD and ISSR were employed to study the genetic diversity and interrelationships among twelve domesticated and three wild mulberry species.  相似文献   
24.
Heavy particle irradiation produces complex DNA double strand breaks (DSBs) which can arise from primary ionisation events within the particle trajectory. Additionally, secondary electrons, termed delta-electrons, which have a range of distributions can create low linear energy transfer (LET) damage within but also distant from the track. DNA damage by delta-electrons distant from the track has not previously been carefully characterised. Using imaging with deconvolution, we show that at 8 hours after exposure to Fe (∼200 keV/µm) ions, γH2AX foci forming at DSBs within the particle track are large and encompass multiple smaller and closely localised foci, which we designate as clustered γH2AX foci. These foci are repaired with slow kinetics by DNA non-homologous end-joining (NHEJ) in G1 phase with the magnitude of complexity diminishing with time. These clustered foci (containing 10 or more individual foci) represent a signature of DSBs caused by high LET heavy particle radiation. We also identified simple γH2AX foci distant from the track, which resemble those arising after X-ray exposure, which we attribute to low LET delta-electron induced DSBs. They are rapidly repaired by NHEJ. Clustered γH2AX foci induced by heavy particle radiation cause prolonged checkpoint arrest compared to simple γH2AX foci following X-irradiation. However, mitotic entry was observed when ∼10 clustered foci remain. Thus, cells can progress into mitosis with multiple clusters of DSBs following the traversal of a heavy particle.  相似文献   
25.

Background  

Heterologous prime-boost immunization protocols using different gene expression systems have proven to be successful tools in protecting against various diseases in experimental animal models. The main reason for using this approach is to exploit the ability of expression cassettes to prime or boost the immune system in different ways during vaccination procedures. The purpose of the project was to study the ability of recombinant vaccinia virus (VV) and bacterial plasmid, both carrying the NS1 gene from tick-borne encephalitis (TBE) virus under the control of different promoters, to protect mice against lethal challenge using a heterologous prime-boost vaccination protocol.  相似文献   
26.
27.
Бор и молибдеп в качестве микроэлементов, а также серпокислый аммоний и азотнокислый натрий в качсетве источников азота оказывали влияние на скорость компостирования пшеничной соломы. Источники азота применялись в таком количестве, что к соломе был прибавлен 1% азота. В опытах с азотнокислым натрием оптимальпая концентрация молибдена составляла 5 р. p. m., с сернокислым аммонием – 1 р. p. m. Максимальное уменьшение количества сухого вещества через 60 дней составляло 50% и было отмечено с азотнокслым натриемпосле прибавления 1 p. p. m. Бора. За пределами оптимального уровня наблюдалось угнетающее или токсическое действие прибавления микроэлемента. Вопрос, целсообразно ли нбавление бора имолибдсна для ускорения компостирования, зависит от их концентрации в органических остатках, в источниках азота, в инокулюоме и в применяемой воде. Значение микроэлементов в энзиматических системах бактерий хорошо известно, но для определения их требований к микроэлементам необходимы более детальные опыты. Несмотря на общераспростаненый взгляд, что растительный материал содеожит достаточное количество микрозлементов для оьеспечения его разложния, предлагаемая работа говорит о том, что для быстрого кобавлять известные их количества, так как во всех применявшихся концентрациях бор и молибден вызывали более значтельныс потерн сухого вещества и общего углерода иконсрвирование более значительного количества общего азота, чем в контроле.  相似文献   
28.
Collagenase-3 (matrix metalloproteinase-13) is a metalloproteinase (MMP) that is associated with bone lesions and exhibits variable expression patterns in odontogenic cysts; it may play a role in regulating focal proliferation and maturation of jaw cyst epithelium. We studied the localization, staining intensity and distribution of collagenase-3 in 13 periapical granulomas with epithelium, 16 periapical granulomas without epithelium and 10 radicular cysts using archived formalin fixed, paraffin embedded tissues. A monoclonal antibody against human collagenase-3 was used to evaluate its expression. Immunohistochemical staining intensities of collagenase-3 in all periapical lesions were (?), 4 (10%); (+), 1 (3%); (++), 22 (56%) and (+++), 12 (31%); differences were not statistically significant. Immunohistochemical distribution of collagenase-3 in epithelial cells was (?), 17 (44%); (+), 17 (44%); (++), 5 (13%); in fibroblasts it was (?), 8 (20%); (+), 23 (59%); (++), 8 (21%); in plasma cells it was (?), 7 (18%); (+), 22 (56%); (++), 10 (26%); in macrophages it was (?), 7 (18%); (+), and 15 (38%); and (++), 17 (44%). Statistically significant differences were found in epithelial cells (p = 0.00) and fibroblasts (p = 0.02), whereas differences were not statistically significant for plasma cells and macrophages. Collagenase-3 may play a role in the conversion of a periapical granuloma with epithelium to radicular cyst. MMP's influence not only epithelial rest cell migration, but also invasion of various stromal cells into granulomatous tissue.  相似文献   
29.
Nucleolar organizer regions are nucleolar components that contain proteins that are stained selectively by silver methods; they can be identified as black dots throughout the nucleolus and are known as silver binding nucleolar organizer regions (AgNOR). The number of AgNOR is related to the cell cycle and the proliferative activity of the cells. We investigated AgNOR using exfoliative cytology smears of potentially malignant oral lesions. Eighty individuals were divided into four equal groups: healthy controls, oral leukoplakia, oral submucous fibrosis and oral squamous cell carcinoma. The mean number of AgNOR in each study group gradually increased from control to oral leukoplakia to oral submucous fibrosis to oral squamous cell carcinoma. The proliferative index was increased in the oral premalignant and malignant patients compared to normal subjects. The mean AgNOR size gradually increased from control to oral leukoplakia to oral submucous fibrosis to oral squamous cell carcinoma. Spherical shaped AgNOR were most common in controls, whereas large, clustered and kidney shapes were most common in oral squamous cell carcinoma. Multiparameter analysis of AgNOR in oral exfoliative smears is a simple, sensitive and cost-effective method for differentiating premalignant from malignant lesions and can be used in conjunction with routine cytomorphological evaluation.  相似文献   
30.
Next-generation sequencing(NGS) technologies have made high-throughput sequencing available to medium- and small-size laboratories, culminating in a tidal wave of genomic information. The quantity of sequenced bacterial genomes has not only brought excitement to the field of genomics but also heightened expectations that NGS would boost antibacterial discovery and vaccine development. Although many possible drug and vaccine targets have been discovered, the success rate of genome-based analysis has remained below expectations. Furthermore, NGS has had consequences for genome quality, resulting in an exponential increase in draft(partial data) genome deposits in public databases. If no further interests are expressed for a particular bacterial genome, it is more likely that the sequencing of its genome will be limited to a draft stage, and the painstaking tasks of completing the sequencing of its genome and annotation will not be undertaken. It is important to know what is lost when we settle for a draft genome and to determine the "scientific value" of a newly sequenced genome. This review addresses the expected impact of newly sequenced genomes on antibacterial discovery and vaccinology. Also, it discusses the factors that could be leading to the increase in the number of draft deposits and the consequent loss of relevant biological information.  相似文献   
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