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1.
The effect of cycloheximide on increased splanchnic prostacyclin release following acute hemorrhage was studied in the rat. Male Sprague-Dawley rats were anesthetized and subjected to acute hemorrhage to 30 mm Hg for 30 min (shock) or sham shock. The superior mesenteric artery was cannulated and removed with its end organ intestine (SV + SI preparation) and perfused in vitro with oxygenated Krebs-Henseleit buffer. Cycloheximide was infused in half of the sham and acute hemorrhage SV + SI preparations at 50 micrograms/ml. Venous effluent from all groups were analyzed for prostanoid release by radioimmunoassay. The SV + SI released 10-fold more 6-keto-prostaglandin (PG) F1 alpha than PGE2 and thromboxane. Acute hemorrhage increased SV + SI release of 6-keto-PGF1 alpha 3-fold compared to sham. Cycloheximide abolished the increased 6-keto-PGF1 alpha following acute hemorrhage but not the basal release in the sham group. Indomethacin decreased PG synthesis in all groups by 90%. Sham PG release was dependent on a stable pool of cyclooxygenase with a long half-life and was not affected by cycloheximide treatment. Acute hemorrhage stimulated a rapid induction of enzymes (cyclooxygenase, prostacyclin synthase) responsible for prostacyclin synthesis and release which were dependent on de novo protein synthesis.  相似文献   
2.
Tics manifest as brief, purposeless and unintentional movements or noises that, for many individuals, can be suppressed temporarily with effort. Previous work has hypothesized that the chaotic temporal nature of tics could possess an inherent fractality, that is, have neighbour-to-neighbour correlation at all levels of timescale. However, demonstrating this phenomenon has eluded researchers for more than two decades, primarily because of the challenges associated with estimating the scale-invariant, power law exponent—called the fractal dimension Df—from fractional Brownian noise. Here, we confirm this hypothesis and establish the fractality of tics by examining two tic time series datasets collected 6–12 months apart in children with tics, using random walk models and directional statistics. We find that Df is correlated with tic severity as measured by the YGTTS total tic score, and that Df is a sensitive parameter in examining the effect of several tic suppression conditions on the tic time series. Our findings pave the way for using the fractal nature of tics as a robust quantitative tool for estimating tic severity and treatment effectiveness, as well as a possible marker for differentiating typical from functional tics.  相似文献   
3.
Lung slices from rats fed a fat-free diet supplemented with safflower oil (control) or tripalmitoyl-glycerol (essential fatty acid [EFA]-deficient) were incubated with [14C] acetate, [14C] palmitate, or [14C] stearate. Of the14C recovered in phospholipids after incubation with [14C] acetate, more than 87% was in 16-carbon fatty acids. Desaturation, as assayed by the percentage of radioactivity in monoenoates in phospholipid fatty acids, was generally double in EFA-deficient slices compared to control slices, regardless of substrate. Desaturation was significantly greater in slices incubated with acetate or octanoate compared to palmitate, indicating that endogenously synthesized palmitate was desaturated more actively than that derived from an exogenous source. Presented in part to the American Physiological Society, Toronto, Canada, October 1980, and published in abstract form inPhysiologist (1980) 23, 135.  相似文献   
4.
In January of 1997, Health Level Seven (HL7) began developing Version 3.0 of its standard. The Version 3 effort represents a transformation of the way that HL7 and its Technical Committees will develop future HL7 information interchange standards. This transformation involves applying object-oriented modelling to the development and specification of information interchange standards. This paper discusses the rationale that led HL7 to undertake this change and provides an overview of the Version 3 Message Development Framework which is HL7's new methodology. It also considers the features of the Version 3 methodology that can facilitate the development of international collaboration and consensus in health informatics standards.  相似文献   
5.
Multiple biologic effects of interferon-alpha (IFN-alpha), including cell growth inhibition and antiviral protection, are initiated by tyrosine phosphorylation of STAT proteins. Although this signal pathway has been intensively investigated, the relevance of STAT signal persistence has received scant attention. Using paired isogenic lymphoma cells (Daudi), which either are sensitive or resistant to growth inhibition by IFN-alpha, we found comparable initial tyrosine phosphorylation of multiple STAT proteins; however, the phosphorylation durations and associated DNA-binding activities diverged. Phosphorylation and DNA-binding capacity of STAT1 decreased after 4 to 8 hours in resistant cells, as compared with 24 to 32 hours in sensitive cells, whereas phosphorylation of STAT3 and STAT5b was briefer in both lines. Functional significance of the prolonged STAT1 signal, therefore, was explored by experimental interruption of tyrosine phosphorylation, either by premature withdrawal of the IFN-alpha or deferred addition of pharmacologically diverse antagonists: staurosporine (protein kinase inhibitor), phorbol 12-myristate 13-acetate (growth promoter), or aurintricarboxylic acid (ligand competitor). Results indicated that an approximately 18-hour period of continued STAT1 phosphorylation was associated with growth arrest, but that antiviral protection developed earlier. These differences provide novel evidence of a temporal dimension to IFN-alpha signal specificity and show that duration of STAT1 activation may be a critical variable in malignant cell responsiveness to antiproliferative therapy.  相似文献   
6.
Results of cascade production and annealing studies for iron are projected to the currently considered fusion reactor first wall materials. Collision cascades initiated by primary knock-on atoms (PKA) with energies above 50 keV, in iron, separate into distinct subregions. Most PKA produced during fission reactor neutron irradiation have energies below 50 keV, but the energies of PKA produced by 14.1 MeV neutron irradiation commonly lie in the 50–500 keV range in iron and vanadium alloys. Computer experiment simulation indicates that, when present, carbon, silicon, and nitrogen, freed by irradiation from bulk precipitates, should tend to re-precipitate on the facets of microvoids which form in cascade subregions during short-term annealing.  相似文献   
7.
Sleep deprivation or "stay awake"-therapy), given in addition to drug therapy, is seen as an effective anti-depressive treatment with actually no side effects. Nevertheless, it is not regularly and systematically used. A reason for this might be doubts about its feasibility in psychiatric hospitals without specialised depression wards. Only a few reports exist on the practical aspects of sleep deprivation. The present article informs about the "stay awake"-therapy on 101 depressive patients (in the mean 25 patient-nights per month), carried out at the Psychiatric Hospital Sanatorium Kilchberg/Zurich. The patients (age between 19 and 76, mean 47 years) participated on average in 4.4 partial sleep deprivations. 72% participated at least for a set of three nights. One staff person takes care of a group of at most five patients. Indication, organisation, night programme, care and possible strains are reported. A stay awake night (three times a week) consists of breakfast, games, conversations, taking two walks, and discussions about depression and about treatment (psychoeducation), with the aim to avoid naps and to provide a pleasant social event. The experiences made with serial partial sleep deprivation are encouraging.  相似文献   
8.
Physical simulation has long been the approach of choice for generating realistic hair animations in CG. A constant drawback of simulation, however, is the necessity to manually set the physical parameters of the simulation model in order to get the desired dynamic behavior. To alleviate this, researchers have begun to explore methods for reconstructing hair from the real world and even to estimate the corresponding simulation parameters through the process of inversion. So far, however, these methods have had limited applicability, because dynamic hair capture can only be played back without the ability to edit, and solving for simulation parameters can only be accomplished for static hairstyles, ignoring the dynamic behavior. We present the first method for capturing dynamic hair and automatically determining the physical properties for simulating the observed hairstyle in motion. Since our dynamic inversion is agnostic to the simulation model, the proposed method applies to virtually any hair simulation technique, which we demonstrate using two state‐of‐the‐art hair simulation models. The output of our method is a fully simulation‐ready hairstyle, consisting of both the static hair geometry as well as its physical properties. The hairstyle can be easily edited by adding additional external forces, changing the head motion, or re‐simulating in completely different environments, all while remaining faithful to the captured hairstyle.  相似文献   
9.
Obtaining efficient transfer of a normal gene and its sustained expression in self-renewing hematopoietic stem cell populations is a central concern for gene therapy initiatives. Potentially, 10(8) to 10(9) CD34+ enriched cells per patient will be required for transduction and subsequent reimplantation. These studies present an efficient method for the transduction of human CD34+ cells that can be used in a clinical study of gene transfer. The method uses a centrifugation-enhanced technique for the retroviral-mediated transfer of the normal human glucocerebrosidase (GC) gene to human CD34+ enriched umbilical cord blood cells (CB). Previous studies had described high expression of GC in CD34+ enriched cells but had not reported transduction efficiency in the progenitor population specifically. The data demonstrate an average transduction efficiency in the progenitor cell population of 50% as measured by polymerase chain reaction (PCR) for the integrated GC-cDNA in clonogenic cells. Measurements of enzyme activity comparing transduced and nontransduced fractions at 6 days posttransduction indicate an average enzyme increase of six-fold over normal background levels. PCR of colony forming units-granulocyte/macrophage (CFU-GM) plated at 6 weeks from long-term culture-initiating cell (LTC-IC) cultures also indicates transfer of the transgene to early progenitor cells. Finally, experiments were carried out with the human erythroleukemia cell line, TF-1, to estimate the durable expression of the transgene. Enzymatic activities in transduced TF-1 cultures remained at 30-fold above the activity of nontransduced controls. The expression persisted for 6 weeks in culture. These studies demonstrate efficient transduction of early progenitor cells and sustained expression of the transgene in cell cultures.  相似文献   
10.
We present a real‐time multi‐view facial capture system facilitated by synthetic training imagery. Our method is able to achieve high‐quality markerless facial performance capture in real‐time from multi‐view helmet camera data, employing an actor specific regressor. The regressor training is tailored to specified actor appearance and we further condition it for the expected illumination conditions and the physical capture rig by generating the training data synthetically. In order to leverage the information present in live imagery, which is typically provided by multiple cameras, we propose a novel multi‐view regression algorithm that uses multi‐dimensional random ferns. We show that higher quality can be achieved by regressing on multiple video streams than previous approaches that were designed to operate on only a single view. Furthermore, we evaluate possible camera placements and propose a novel camera configuration that allows to mount cameras outside the field of view of the actor, which is very beneficial as the cameras are then less of a distraction for the actor and allow for an unobstructed line of sight to the director and other actors. Our new real‐time facial capture approach has immediate application in on‐set virtual production, in particular with the ever‐growing demand for motion‐captured facial animation in visual effects and video games.  相似文献   
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