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331.
Lactic acid production has been carried out using (a) Lactobacillus delbruckii, (b) optimal production medium comprised of 10% carbon source derived from sweet sorghum (SS) (Sorghum bicolor)/golden syrup (GS; molasses after glucose crystallization)/date palm (DP) juice (Phoenix dactylifera L.), 1% yeast extract, 0.6% sodium acetate, 0.5% KH2PO4, and 0.5% MgSO4 · 7H2O, (c) in batch mode, (d) at 45 ± 1°C, 150 rpm, anaerobic condition, and pH 5.5 ± 0.1, and (e) sterilized CaCO3 powder at regular intervals for neutralization to promote optimal utilization of sugar. The lactic acid (LA) productivity was higher from the use of GS and less from SS as well as DP juice. Decolorization of carbon sources prior to use in fermentation gave LA, meeting food grade specifications.  相似文献   
332.
Skeletal muscle wasting in patients receiving maintenance hemodialysis (HD) has been well documented. The rationale for prescribing progressive resistance training (PRT) in this cohort in an attempt to reverse this catabolism and induce a wide spectrum of physiological, functional, and psychological health-related adaptations is extremely strong. Unfortunately, the barriers to exercise adoption in this cohort are many, which may explain the persisting sedentariness of this population and the lack of widespread clinical programs such as are now commonplace in cardiac rehabilitation and pulmonary rehabilitation units. Current health care practices for HD patients do not address the negative health issues of inactivity and muscle wasting. Therefore, we conducted the first randomized-controlled trial to prescribe PRT during maintenance HD treatment. The purpose of this paper is to present the rationale and methodology that we utilized for implementing intradialytic PRT in a conventional outpatient HD clinic. Potential areas for modification of PRT regimens in this setting are also presented.  相似文献   
333.
A rectilinear ion trap (RIT) mass analyzer was incorporated into a mass spectrometer fitted with an electrospray ionization source and an atmospheric pressure interface. The RIT mass spectrometer, which was assembled in two different configurations, was used for the study of biological compounds, for which performance data are given. A variety of techniques, including the use of a balanced rf, elevated background gas pressure, automatic gain control, and resonance ejection waveforms with dynamically adjusted amplitude, were applied to enhance performance. The capabilities of the instrument were characterized using proteins, peptides, and pharmaceutical drugs. Unit resolution and an accuracy of better than m/z 0.2 was achieved for mass-to-charge (m/z) ratios up to 2000 Th at a scan rate of approximately 3000 amu/(charge.s) while reduced scan rates gave greater resolution and peak widths of less than m/z 0.5 over the same range. The mass discrimination in trapping externally generated ions was characterized over the range m/z 190-2000 and an optimized low mass cutoff value of m/z 120-140 was found to give equal trapping efficiencies over the entire range. The radial detection efficiency was measured as a function of m/z ratio and found to rise from 35% at low m/z values to more than 90% for ions of m/z 1800. The way in which the ion trapping capacity depends on the dc trapping potential was investigated by measuring the mass shift due to space charge effects, and it was shown that low trapping potentials minimize space charge effects by increasing the useful volume of the device. The collision-induced dissociation (CID) capabilities of the RIT instrument were evaluated by measuring isolation efficiency as a function of mass resolution as well as measuring peptide CID efficiencies. Overall CID efficiencies of more than 60% were easily reached, while isolation of an ion with unit resolution at m/z 524 was achieved with high rejection (>95%) of the adjacent ions. The overall analytical capabilities of the ESI-RIT instrument were demonstrated with the analysis of a mixture of pharmaceutical compounds using multiple-stage mass spectrometry.  相似文献   
334.
The tensile stress–strain and recovery behavior of all the four commercial varieties of Indian silk fibers, namely Mulberry, Tasar, Eri, and Muga, have been studied along with their structures. Compared to the non‐Mulberry silk fibers, Mulberry silk fiber is much finer and has crystallites of smaller size, higher molecular orientation, and a more compact overall packing of molecules. These structural differences have been shown to result in (1) the presence of a distinct yield and a yield plateau in non‐Mulberry silk and their absence in Mulberry silk, and (2) relatively higher initial modulus and tenacity along with lower elongation‐to‐break and toughness and superior elstic recovery behavior of mulberry silk compared to non‐Mulberry silk. It is also observed that fine silk fibers have a relatively more ordered and compact structure with higher orientation compared to their coarse counterparts, and this gives rise to higher initial modulus and higher strength in the finer fibers. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2418–2429, 2000  相似文献   
335.
We present a communication library to improve performance of PVM. The new library introduces communication primitives based on Active Messages. We propose a hybrid scheme that includes a signal driven message notification scheme plus controlled polling. The new communication library is tested along with the normal PVM library to assess the improvement in performance.  相似文献   
336.
Metabolites orchestrate cellular processes as either substrates, co-enzymes, inhibitors, or activators of cellular proteins such as enzymes and receptors. Although traditional biochemical and structural biology-based approaches have been successfully employed for the discovery of protein-metabolite interactions, they often fail to detect transient and low-affinity biomolecular relationships. Another limitation of these approaches is that they are performed under in vitro conditions lacking the physiological context. Recently developed mass spectrometry-based methodologies overcome both these shortcomings, and have resulted in the discovery of global protein-metabolite cellular interaction networks. Herein, we describe traditional and modern approaches for the discovery of protein-metabolite interactions, and discuss the impact of these discoveries on our understanding of cellular physiology and on drug development.  相似文献   
337.
Lipids are key constituents of numerous biomedical drug delivery technologies. Here, we present the design, synthesis and biophysical characterizations of a library of cationic lipids containing an acetal residue in their linker region. These cationic acetal lipids (CALs) were conveniently prepared through a trans-acetalization protocol from commercially available precursors. NMR studies highlighted the conformational rigidity at the acetal residue and the high hydrolytic stability of these CALs. Fluorescence anisotropy studies revealed that the CAL with a pyridinium headgroup (CAL1) formed highly cohesive vesicular aggregates in water. These structural and self-assembly features of the CAL1 allowed up to 196 % w/w loading of curcumin (Cur) as a representative hydrophobic drug. A reconstitutable formulation of Cur was obtained as a result, which could deliver the drug inside mammalian cells with very high efficiency. The hemocompatibility and cytocompatibility of CAL1 was significantly enhanced by creating a coating of polydopamine (PDA) onto its vesicular assemblies to produce hybrid lipid-polymer nanocapsules. This work demonstrates rapid access to the useful synthetic lipid formulations with high potential in drug and gene delivery applications.  相似文献   
338.
The reliable correlation between personality and brain signal ensures that inferences from cognitive processes can be achieved. This research aims primarily to predict one's personality using brain signals. On grounds of Psychology, the inference of personality in this work is performed on the basis of the Myers–Briggs Type Indicator (MBTI) personality inventory. Personality consists of different types of thinking, feeling and behavior patterns. EEG signals are produced when a person is exposed to situations or scenarios via visual information and experiences various emotions or sentiments. In this study, by evaluating brain waves while a person watches personality traits elicitation materials, the identification of the personality traits of an individual is done. The elicitation materials used for the collection of the dataset comprise approximately 50 videos with the pre-defined personality of the dramatic personae and therefore, it is considered to be the ground truth for the experimental procedure of this work. For creating a dataset, sixty participants contributed and gave brain signals. The GP model with the proposed BSH crossover, known as the BSHGP model, is implemented. The maximum performance of the BSHGP model for a 10-fold partition scheme is 84.34%.  相似文献   
339.
Chronic white adipose tissue (WAT) inflammation has been recognized as a critical early event in the pathogenesis of obesity-related disorders. This process is characterized by the increased residency of proinflammatory M1 macrophages in WAT. However, the lack of an isogenic human macrophage-adipocyte model has limited biological studies and drug discovery efforts, highlighting the need for human stem cell-based approaches. Here, human induced pluripotent stem cell (iPSC) derived macrophages (iMACs) and adipocytes (iADIPOs) are cocultured in a microphysiological system (MPS). iMACs migrate toward and infiltrate into the 3D iADIPOs cluster to form crown-like structures (CLSs)-like morphology around damaged iADIPOs, recreating classic histological features of WAT inflammation seen in obesity. Significantly more CLS-like morphologies formed in aged and palmitic acid-treated iMAC-iADIPO-MPS, showing the ability to mimic inflammatory severity. Importantly, M1 (proinflammatory) but not M2 (tissue repair) iMACs induced insulin resistance and dysregulated lipolysis in iADIPOs. Both RNAseq and cytokines analyses revealed a reciprocal proinflammatory loop in the interactions of M1 iMACs and iADIPOs. This iMAC-iADIPO-MPS thus successfully recreates pathological conditions of chronically inflamed human WAT, opening a door to study the dynamic inflammatory progression and identify clinically relevant therapies.  相似文献   
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