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51.
This study used multilevel modeling to examine process and treatment adherence factors as predictors of collateral partner reports of abuse following participation in a cognitive-behavioral group treatment program for partner violent men (N = 107). Therapist working alliance ratings predicted lower levels of physical and psychological abuse at the 6-month follow-up and were the strongest predictors of outcome. Homework compliance partially mediated associations between early alliance ratings and psychological abuse at follow-up. Greater group cohesion during treatment, assessed by client report, also predicted lower physical and psychological abuse at follow-up. The findings support the promotion of a collaborative therapeutic environment to induce change among partner violent men. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
This study was designed to investigate whether spatial skill, math anxiety, and math self-confidence functioned as mediators of a significant gender difference in the Mathematics Scholastic Aptitude Test (SAT-M) among the top third of a college-bound sample. Using path analytic techniques, the decomposition of the significant gender—SAT-M correlation into direct and indirect effects indicated that there were no direct effects of gender on SAT-M. Mental rotation and math self-confidence showed indirect effects, mediating the gender—SAT-M relationship; math anxiety did not. Of these indirect effects, 36% was mediated by math self-confidence; 64% by mental rotation. For both these variables, most of the mediational effects of the gender—SAT-M relationship did not occur by way of the causal pathway leading through geometry grades. Thus, the mediational effects cannot simply be attributed to the presence of geometry items on the SAT-M or to math self-confidence acquired during prior geometry coursework. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
53.
We review recent experiments in which superfluid $^3$ He has been studied under highly controlled confinement in nanofluidic sample chambers. We discuss the experimental challenges and their resolution. These methods open the way to a systematic investigation of the superfluidity of $^3$ He films, and the surface and edge excitations of topological superfluids.  相似文献   
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Gold nanoparticles have garnered interest as both radiosensitzers and computed tomography (CT) contrast agents. However, the extremely high concentrations of gold required to generate CT contrast is far beyond that needed for meaningful radiosensitization, which limits their use as combined therapeutic–diagnostic (theranostic) agents. To establish a theranostic nanoplatform with well‐aligned radiotherapeutic and diagnostic properties for better integration into standard radiation therapy practice, a gold‐ and superparamagnetic iron oxide nanoparticle (SPION)‐loaded micelle (GSM) is developed. Intravenous injection of GSMs into tumor‐bearing mice led to selective tumoral accumulation, enabling magnetic resonance (MR) imaging of tumor margins. Subsequent irradiation leads to a 90‐day survival of 71% in GSM‐treated mice, compared with 25% for irradiation‐only mice. Furthermore, measurements of the GSM‐enhanced MR contrast are highly predictive of tumor response. Therefore, GSMs may not only guide and enhance the efficacy of radiation therapy, but may allow patients to be managed more effectively.  相似文献   
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Effects of liquid swine manure on dissipation of 17β-estradiol in soil   总被引:1,自引:0,他引:1  
17β-estradiol (E2), a natural estrogenic hormone, degrades within hours and bind strongly to soils and sediments; however, estrogens are frequently detected in the environment at concentrations that impact water quality. Colloidal (COC) and dissolved (DOC) organic carbon may enhance the persistence and mobility of E2. Soil batch experiments were used to identify the persistence and sorption of radiolabeled E2 dissolved in solutions of (i) COC/DOC derived from liquid swine manure and (ii) CaCl(2). Estradiol disappeared from the aqueous phase before 7 d in the CaCl(2) solution, yet persisted throughout the duration of the 14 d experiment in the liquid manure solution. There was also concomitant formation of estrone (E1; a metabolite of E2) as E2 dissipated in sterile batch experiments, which was attributed to abiotic oxidation. The liquid manure solution appeared to interact with the estrogen and/or oxidation reaction sites, reducing E2 degradation. Furthermore, the liquid manure solution reduced E2/E1 binding to the soil surface resulting in more E2/E1 in the aqueous layer compared to the CaCl(2) solution. Ultrafiltration results of liquid manure indicated that ~1/3 of E2 was associated with COC, which may be responsible for the reduced degradation and sorption of E2 in the liquid manure solution.  相似文献   
58.
Mammary remodeling in dairy cows involves coordinated changes in stromal and epithelial tissue. Tissue remodeling is characterized by changes in cell proliferation, activation of fibroblasts into myofibroblasts, and changes in extracellular matrix content. Transforming growth factor β-1 (TGF-β1) increases differentiation of fibroblasts to myofibroblasts, regulates expression of extracellular matrix proteins and proteases, and has cell-type dependent effects on proliferation. The objective of this study was to determine whether TGF-β1 treatment of mammary tissue from cows in late lactation and the dry period affects cell proliferation, expression of matrix metalloproteinase-3 (MMP-3) and fibronectin (FN), and the differentiation of fibroblasts into myofibroblasts that express smooth muscle α actin (SMA). Tissue was biopsied from 7 Holstein cows at 4 time points: late lactation, 1 wk after dry-off, 3 wk before expected calving, and 1 wk before expected calving. Explants of biopsied tissue were incubated for 2 h in Waymouth's medium containing insulin, hydrocortisone, and 0 or 5 ng of TGF-β1/mL; a subset of cultures was also incubated with bromodeoxyuridine to measure epithelial and stromal cell proliferation. Tissues were fixed, embedded in paraffin, sectioned, and stained by immunohistochemistry. Stage at biopsy had an overall effect on rate of epithelial and stromal cell proliferation, and TGF-β1 treatment increased rate of bromodeoxyuridine incorporation more than 2-fold in both cell types at 1 wk after dry-off. The number of fibroblasts expressing SMA was 19% higher in the intralobular stroma at 1 wk after dry-off compared with that at 1 wk before expected calving, and the percentage of activated fibroblasts tended to be higher in tissue incubated with TGF-β1. Biopsy stage had an overall effect on percentage area of epithelium expressing FN and MMP-3. Incubation with TGF-β1 had no effect on percentage intralobular stroma area expressing FN or MMP-3. Effects of TGF-β1 treatment were most apparent at 1 wk after dry-off, indicating that the first week of dry period may be an ideal target for testing effects in vivo.  相似文献   
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Ascites from ovarian cancer patients contain potent growth-promoting activity toward human ovarian cancer cells both in vitro and in vivo. This activity is associated with rapid increases in cytosolic free calcium ([Ca2+]i) as a consequence of phosphoinositide hydrolysis. In this study, we describe the purification, characterization, and identification of an ovarian cancer activating factor (OCAF) from ascites of ovarian cancer patients. We have isolated OCAF by a combination of solvent extraction, silica gel chromatography, and TLC. Mass spectral analysis, phospholipase sensitivity, and gas chromatographic behavior of purified OCAF indicate that OCAF is composed of various species of lysophosphatidic acid (LPA), including LPAs with polyunsaturated fatty acyl chains (linoleic, arachidonic, and docosahexaenoic acids). However, OCAF is more potent than sn-1 palmitoyl, oleoyl, or stearoyl LPA in increasing [Ca2+]i in ovarian cancer cells. The ability of OCAF to alter [Ca2+]i is sensitive to the effects of lipoxidase, whereas the activity of sn-1 oleoyl, stearoyl, or palmitoyl LPA is not, suggesting that polyunsaturated bonds in the fatty acyl chain of OCAF may account for its increased ability to activate ovarian cancer cells. Furthermore, a sn-2 linoleoyl LPA generated by phospholipase A1 treatment of synthetic phosphatidic acid is much more active than are sn-1 palmitoyl, stearoyl, or oleoyl LPA in increasing [Ca2+]i in ovarian cancer cells. Taken together, these data suggest that the ability of OCAF to increase cellular calcium may reside in the structure and/or location of the fatty acyl chain of LPA. Purified OCAF, at concentrations similar to those present in ascites from ovarian cancer patients, was sufficient to induce proliferation of ovarian cancer cells, as indicated by thymidine incorporation, reduction of 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide, or colony formation. However, even at optimal concentrations of OCAF, proliferation was lower than that induced by FCS or ascites from ovarian cancer patients, indicating that, although OCAF may be a major regulator of ovarian cancer cells in vivo, it is not the sole mediator present in ascites, and it likely functions in concert with other growth factor activities.  相似文献   
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