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881.
Hofer Katharina Maria Smejkal Angela Elisabeth Bilgin F. Zeynep Wuehrer Gerhard A. 《Scientometrics》2010,84(3):845-862
This study does a bibliometric analysis based on keywords of conference proceedings. Scientometric investigations of conference
proceedings are a new and innovative, not very common approach. The studies and papers presented may be interpreted as early
indicators of scientific development. The Academy of International Business (AIB) was chosen for being the leading organization
for studies in international business with contributions covering a 3-year period (2006–2008). The study presents the general
structure of current scholarly interest in international business studies, clusters the keywords and reflects details on the
focused research areas of the papers analyzed. The bibliometric analysis indicates three clusters: the core, the semi-periphery
and the periphery. The five most occurring keywords were found to be multinational enterprise, emerging markets, foreign direct
investment, internationalization and knowledge management in descending order. The analyses focus on concepts building the
core (in total ten keywords), the semi-periphery which is coined by performance and related topics (60 keywords) and the periphery
of the studies with governance and specific facets of it (199 keywords). 相似文献
882.
883.
884.
Due to growing problems with new emerging pathogens, cost-effective and manageable methods for their accurate identification in routine diagnostics are urgently required. Of particular importance is the genus Mycobacterium with its more than 100 species. Identification of these species is hampered by their slow growth in the laboratory and by the obligate need for DNA sequence analysis. To provide a fast and reliable diagnostic tool, we developed a novel approach using fluorescently labeled DNA hairpin structures (smart probes) for selective and sensitive detection of mycobacterial 16S rDNA PCR amplicons in homogeneous and heterogeneous assays. Smart probes are singly labeled hairpin-shaped oligonucleotides bearing a fluorescent dye at the 5'-end, which is quenched by guanosine residues in the complementary stem. Upon hybridization to target sequences, a conformational change occurs reflected in an increase in fluorescence intensity. Using optimized parameters for hybridization experiments we established a reliable method for the specific detection of Mycobacterium tuberculosis (M. tuberculosis complex) and Mycobacterium xenopi (member of the atypical mycobacteria) with a detection sensitivity of approximately 2 x 10(-8) M in homogeneous solution. The specificity of the smart probes designed is demonstrated by discrimination of M. tuberculosis and M. xenopi against 15 of the most frequently isolated mycobacterial species in a single assay. In combination with a microsphere-based heterogeneous assay format, the technique opens new avenues for the detection of pathogen-specific DNA sequences with hitherto unsurpassed sensitivity. 相似文献
885.
The diffusing capacity for carbon monoxide is partially dependent on lung volume at which it is measured. As a consequence, the diffusing capacity for carbon monoxide is often indexed to the simultaneously measured lung volume (VA), giving rise to the term DL/VA. This reflects the diffusing capacity of carbon monoxide per unit area of lung parenchyma. The authors investigated the pulmonary function of 18 patients who had an elevated DL/VA in order to identify factors that could account for this abnormality. Sixteen of the 18 had a reduction in vital capacity. The vital capacity was reduced because of obesity, pleural disease, and diaphragmatic dysfunction. Eight of nine patients with a body mass index > 30 kg/m2 had a reduction in vital capacity. On the basis of these findings, we believe that an elevated DL/VA should alert the physician to the possibility of 1) an increase in pulmonary capillary blood volume (Vc) (obesity, polycythemia, negative pleural pressure), and 2) reduced VA that does not directly affect the pulmonary capillary bed (pleural disease, neuromuscular disease). 相似文献
886.
Klipper E Gilboa T Levy N Kisliouk T Spanel-Borowski K Meidan R 《Reproduction (Cambridge, England)》2004,128(4):463-473
Endothelium-derived endothelin-1 (ET-1) and nitric oxide (NO) are pivotal regulators of corpus luteum (CL) function. To have a better insight into their synthesis and action, members of the ET system (ET-1, ET converting enzyme (ECE-1) isoforms a-d, ETA and ETB receptors) along with NO synthase (NOS) isoforms--endothelial (e)NOS and inducible (i)NOS--were quantified in CL-derived endothelial cells (CLEC). The expression of these genes in microvascular CLEC, obtained by lectin-coated magnetic beads, was compared with cells removed from the luteal microenvironment and maintained in culture for different durations, and with endothelial cells (EC) derived from a large blood vessel (i.e. bovine aortic endothelial cells, BAEC). The profile of gene expression in the different EC types was determined by quantitative real-time PCR. Freshly isolated EC from mid-cycle CL exhibited high ET-1 receptor expression (both ETA and ETB), low ET-1 synthesizing ability (both prepro (pp) ET-1 and ECE-1), but elevated iNOS - the high throughput NOS isoform. The distinct phenotype of CLEC was lost soon after an overnight culture. ETA and ETB receptor levels declined, ppET-1 levels increased while iNOS was reduced. These changes were extenuated during long-term culture of CLEC. The general pattern of gene expression in BAEC and long-term cultured CLEC was similar yet some differences, reminiscent of freshly isolated CLEC, remained: ECE-1c, ETB receptor and NOS isoforms were expressed differently in BAEC as compared with lines of CLEC. This study suggests that the luteal microenvironment is necessary to sustain the selective phenotype of its resident endothelial cells. The inverse relationship between ppET-1 and iNOS observed in freshly isolated CLEC and in cultured cells is physiologically significant and suggests that ET-1 and NO may modulate the production of each other. 相似文献
887.
Bornhop DJ Griffin JM Goebel TS Sudduth MR Bell B Motamedi M 《Applied spectroscopy》2003,57(10):1216-1222
Lanthanide chelates are a somewhat unique class of molecules that have proven to be useful in the biomedical field due to their extremely large Stokes' shift and long fluorescent lifetimes. The ability of these molecules to produce fluorescence in the low- or zero-back-ground regime makes this class of molecules excellent candidates for use as contrast agents for a wide variety of applications in biological settings. Here we present the preparation, spectroscopic characterization, and application of a new terbium chelate contrast agent, based on the 1,4,7,10-tetraazacyclododecane macrocycle (cyclen), for detection of early-stage malignant lesions in the Syrian hamster cheek pouch. Tb-P(CTMB) delivers bright blue-green luminescence when excited with low photon fluxes of UV light. As a pilot study, the DMBA-treated Golden Hamster Cheek pouch epithelial cancer model was employed and Tb-P(CTMB) was used as a topical agent for the visual detection of diseased tissue. In this preliminary study the agent tended to associate with early-stage malignant lesions, suggesting that Tb-P(CTMB) could be used as a contrast agent to aid in identifying early-stage oral cancer lesions. 相似文献
888.
RA Stahel LM Jost H Honegger E Betts ME Goebel A Nagler 《Canadian Metallurgical Quarterly》1997,15(5):1730-1735
PURPOSE: To evaluate the effect of two filgrastim dosages after autologous bone marrow transplantation (ABMT) in patients with Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Eighty-six patients were enrolled onto a multicenter, randomized, open-label study. The study compared the efficacy and safety of two different doses of filgrastim, 5-microgram/kg/d subcutaneous (SC) bolus injection and 10-microgram/kg/d SC continuous infusion, starting on day 1 following ABMT. RESULTS: Both patient groups were well matched in terms of demography and disease. The results showed no statistical difference in the median time to reach an absolute neutrophil count (ANC) of 0.5 x 10(9)/L (11 days; P = .685) and no difference in the median duration of neutropenia (10 v 11 days, respectively; P = .567) between either dose of filgrastim. The incidence and duration of fever and neutropenic fever were the same in both groups. The number and mean duration of clinically and documented infections, duration of intravenous (IV) antibiotics, time to discharge from hospital, and tumor response also were similar in both groups. CONCLUSION: This study demonstrates that a dose of filgrastim 5 micrograms/kg/d administered as a daily SC bolus injection has a similar efficacy and safety profile compared with the 10-microgram/kg/d dose administered as a SC continuous infusion. The lower dose of filgrastim has potential cost-saving implications in terms of both the dose of drug administered and the ease of administration. Based on these findings, the recommended dose of filgrastim after ABMT should be 5 micrograms/kg/d. 相似文献
889.
The Application of Microemulsions as a Washing-System in the Finishing Industry In the textile finishing in many areas dispers systems are been used or develop during the processing. Examples are the dyeing bath for polyester fibers in which hydrophobic dyestuff acts as an dispersion in water. Another example for such a system occurs during washing. In such a case the oil-surfactant-water system changes from a solution of surfactant in water into oil-in-water emulsion as a function of dwelling-time. The present paper discusses the usefulness of a one phase water-oil-surfactant system in textile finishing processes. In detail a physico-chemical characterisation of a many component system consisting of water/hydrophob/amphiphil (surfactant)/electroyte is been needed. The behaviour of such systems is dependent on the chemical structure of the components and of pressure and temperature. Those systems show one-, two- and threephase regions. In this paper evidence will be given that the conditions having the highest degree of efficiency toward cleanness of the textile goods occurs in the one-phase region close to the three phase transition. 相似文献
890.
Zieve's syndrome (ZS), which consists of transient haemolytic anaemia, jaundice, hyperlipoproteinaemia, and alcohol-induced liver disease, was studied in male patients during the acute (n = 20) and the remittent (n = 10) phase. Chronic alcoholics (n = 10) without haemolysis and healthy male persons (n = 10) served as controls. Erythrocytes were separated into old and young cells by means of density-layer centrifugation. Those fractions which contained older red cells disclosed a pyruvate-kinase instability which resulted in impaired metabolism. Changes in membrane lipid composition as indicated by increased cholesterol and polyunsaturated fatty acids (PUFA) were also detected in patients during the acute phase of ZS. Alcohol-induced red-cell vitamin-E deficiency with a decrease in PUFA levels may provoke an oxidation of reduced red-cell glutathione which in turn results in the enzyme instability. This study lends further support to the hypothesis that the putative role of the red-cell metabolic injury in the origin of haemolysis in ZS cannot be envisaged without introducing membrane-linked and extracellular cofactors. 相似文献