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1.
The effects of psychological stress on eosinophilic gastrointestinal disorders have not been elucidated. This study investigated the effects of psychological stress in a mouse model of eosinophilic enteritis (EoN). BALB/c mice were treated with ovalbumin (OVA) to create an EoN model and subjected to either water avoidance stress (WAS) or sham stress (SS). Microscopic inflammation, eosinophil and mast cell counts, mRNA expression, and protein levels of type 2 helper T cell (Th2) cytokines in the ileum were compared between groups. We evaluated ex vivo intestinal permeability using an Ussing chamber. A corticotropin-releasing hormone type 1 receptor (CRH-R1) antagonist was administered before WAS, and its effects were analyzed. WAS significantly increased diarrhea occurrence and, eosinophil and mast cell counts, and decreased the villus/crypt ratio compared to those in the SS group. The mRNA expression of CRH, interleukin IL-4, IL-5, IL-13, eotaxin-1, and mast cell tryptase β2 significantly increased, and the protein levels of IL-5, IL-13, and OVA-specific immunoglobulin E (IgE) also significantly increased in the WAS group. Moreover, WAS significantly increased the intestinal permeability. The CRH-R1 antagonist significantly inhibited all changes induced by WAS. Psychological stress exacerbated ileal inflammation via the CRH-mast cell axis in an EoN mouse model.  相似文献   
2.
Osteoporosis is a common bone disease, particularly in menopausal women. Herein, we screened four Kampo medicines (Unkeito (UKT), Kamishoyosan (KSS), Kamikihito (KKT), and Ninjinyoeito (NYT)), frequently used to treat menopausal syndromes, for their effects on receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclast differentiation in RAW 264 cells. Considering that UKT exhibited the most potent effect, we examined its effect on RANKL-induced osteoclastogenesis, the induction of osteoclast apoptosis, and the mechanisms underlying its effects. UKT inhibits RANKL-induced osteoclast differentiation in the early stage and decreases osteoclast-related genes, including tartrate-resistant acid phosphatase (Trap), dendritic cell-specific transmembrane protein (Dcstamp), matrix metalloproteinase-9 (Mmp9), and cathepsin K (Ctsk). Specifically, UKT inhibits the nuclear factor of activated T cells 1 (NFATc1), which is essential for osteoclastogenesis. UKT increases Bcl6, which antagonizes NFATc1 and Dc-stamp, thereby blocking the progression of osteoclasts to maturation. UKT also decreased nuclear translocation by downregulating the activity of p65/NF-κB. In addition, UKT enhances mononuclear osteoclast apoptosis via activation of caspase-3. Herein, we demonstrate that UKT suppresses RANKL-mediated osteoclastogenesis via the Blimp1–Bcl6 and NF-κB signaling pathways and enhances mononuclear osteoclast apoptosis. Furthermore, UKT prevents bone loss in OVX mice. Thus, UKT might be a potential therapeutic agent for postmenopausal osteoporosis.  相似文献   
3.
In recent time, a great deal of research effort has been directed toward promptly facilitating post-disaster communication by using wireless mesh networks (WMNs). WMN technology has been considered to be effectively exploited for this purpose as it provides multi-hop communication through an access network comprising wireless mesh routers, which are connected to the Internet through gateways (GWs). One of the critical challenges in using WMNs for establishing disaster-recovery networks is the issue of distributing traffic among the users in a balanced manner in order to avoid congestion at the GWs. To overcome this issue, we envision a disaster zone WMN comprising a network management center. First, we thoroughly investigate the problem of traffic load balancing amongst the GWs in our considered disaster zone WMN. Then, we develop traffic load distribution techniques from two perspectives. Our proposal from the first perspective hinges upon a balanced distribution of the bandwidth to be allocated per user. On the other hand, our second perspective considers the dynamic (i.e., varying) bandwidth demands from the disaster zone users that requires a more practical and refined distribution of the available bandwidth by following an intelligent forecasting method. The effectiveness of our proposals is evaluated through computer-based simulations.  相似文献   
4.
The paper presents a comparative analysis of two advanced ICT nations, Japan and Denmark. While Japan is very advanced with respect to its telecommunications infrastructure, Denmark has come further than Japan regarding the use of ICT infrastructures. This paper compares Denmark, a leader in ICT usage, and Japan, which lags in that regard, analyzes differences in institutions, technologies, and services offered, and examines factors contributing to the success of Denmark in promoting ICT usage from a Japanese perspective. Strong governmental leadership, and common techno-infrastructure such as personal ID and digital signature that serve different systems, and user-orientation of service design are the characteristics of Danish efforts absent in Japan.  相似文献   
5.
Error-free transmission through 10-km single-mode fiber at 10 Gb/s under -13-dB optical reflections has been demonstrated for the first time using a directly modulated 1.3-/spl mu/m InP-based VCSEL without any optical isolator. The 13-GHz relaxation oscillation frequency and stable polarization suppresses relative intensity noise degradation under optical reflection. Only 1-dB error-free power penalty has been observed with optical reflection set with the worst polarization direction.  相似文献   
6.
Micafungin (FK463), a novel water-soluble echinocandin-like lipopeptide, exerted fungicidal action toward growing cells of Candida albicans at concentrations of 0.1 microg ml(-1) or above. The drug at these levels induced osmotically fragile cells and the resulting fungicidal effect was partially reversed when cultures were grown in the presence of an osmotic stabilizer. Candida cells incubated with fungicidal concentrations of micafungin gradually increased in size and/or became deformed. An electron microscopic study of such micafungin-treated cells revealed morphological alterations in the cell wall; deformation in contour, abnormal septum formation and decrease in thickness of the intermediate layer of the cell wall were prominent. In addition, the structure of cell membranes as well as of membranous cytoplasmic organelles was slightly impaired. These data suggest that micafungin principally affects the normal formation of the cell wall in growing Candida cells.  相似文献   
7.
A series of new amphoteric surfactants having a phosphoric acid group, a tertiary amino group and a 2-hydroxyalkyl group, sodium 2-(N-2-hydroxyalkyl-N-methyl-amino)ethyl hydrogen phosphates (alkyl: n-tetradecyl, n-hexadecyl, n-octadecyl), were prepared by an addition reaction of 1,2-epoxyalkanes to N-methylaminoethanol, followed by the introduction of a phosphoric acid group and neutralization with sodium hydroxide. The structures of these compounds were confirmed by spectroscopy and elemental analysis. The solubility in solvents, Krafft point, surface tension, critical micelle concentration (CMC), occupation area of the molecule at the surface of aqueous solutions and foaming power were measured. It was shown that a 2-hydroxyethyl group in a long alkyl chain seemed to behave as a hydrophobic part.  相似文献   
8.
In this paper, we investigate the influence of hypercapnia on the early and late phases of the phrenic neurogram using the matching pursuit (MP) method in the decebrated piglets. The phrenic neurogram was recorded from 8 piglets (4-7 days old) during control (40% O2 with 5% end-tidal CO2), the mild hypercapnia (40% O2 with 7% end-tidal CO2), and the severe hypercapnia (40% O2 with 15% end-tidal CO2). The time-frequency representations, atoms, of the phrenic neurogram are calculated from the 5 consecutive phrenic neurogram burst for each piglet for each condition using the MP method after vagotomy and chemodenervation. Our results show that the energy percentage of atoms representing the nonperiodic neural activities (NPNAs) significantly increased when the CO2 concentration was shifted from 7% to 15% in the early phase (the first half) of the phrenic neurogram. In addition, the energy percentage of atoms representing the periodic neural activities (PNAs) decreased in the late phase (the second half) when the CO2 concentration was shifted from 7% to 15% (p < 0.01). As a summary, our result suggest that hypercapnia results in significant changes in the phrenic neurogram, an output of the respiratory neural networks in the medulla, both in time and frequency domians during early maturation.  相似文献   
9.
Novel highly branched biodegradable macromolecular systems have been developed by grafting carboxymethylchitosan (CMCht) onto low generation poly(amidoamine) (PAMAM) dendrimers. Such structures organize into sphere‐like nanoparticles that are proposed to be used as carriers to deliver bioactive molecules aimed at controlling the behavior of stem cells, namely their proliferation and differentiation. The nanoparticles did not exhibit significant cytotoxicity in the range of concentrations below 1 mg mL?1, and fluorescent probe labeled nanoparticles were found to be internalized with highly efficiency by both human osteoblast‐like cells and rat bone marrow stromal cells, under fluorescence‐activated cell sorting and fluorescence microscopy analyses. Dexamethasone (Dex) has been incorporated into CMCht/PAMAM dendrimer nanoparticles and release rates were determined by high performance liquid chromatography. Moreover, the biochemical data demonstrates that the Dex‐loaded CMCht/PAMAM dendrimer nanoparticles promote the osteogenic differentiation of rat bone marrow stromal cells, in vitro. The nanoparticles exhibit interesting physicochemical and biological properties and have great potential to be used in fundamental cell biology studies as well as in a variety of biomedical applications, including tissue engineering and regenerative medicine.  相似文献   
10.
We propose a novel vertical-cavity surface emitting laser (VCSEL) with Al(Ga)As multi-oxide layer (MOX) structure for the purpose of enlarging window aperture maintaining single transverse mode operation. We have fabricated an InGaAs-GaAs VCSEL with the proposed MOX structure formed on GaAs (311)B substrate. We have performed a numerical simulation to investigate single-mode behavior of the proposed structure and showed a possibility of single-mode VCSEL's with a large active area. We have fabricated an 11-μm current aperture 960-nm wavelength VCSEL with this MOX structure. The threshold current and voltage were 1.0 mA and 2.0 V, respectively, which are comparable to those of conventional oxide VCSELs. In 8-μm aperture, single-mode operation was maintained with a driving current up to four times the threshold  相似文献   
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