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991.
McConnell Allen R.; Sherman Steven J.; Hamilton David L. 《Canadian Metallurgical Quarterly》1997,72(4):750
It is hypothesized that perceptions of entitativity (i.e., seeing social targets as possessing unity and coherence) have important implications for how one organizes information about, and forms impressions of, individual and group targets. When perceivers expect entitativity, they should form an integrated impression of the target, resulting in on-line judgments. However, when perceivers expect little entitativity, they should not process target-relevant information in an integrative fashion, resulting in memory-based judgments. Although many factors affect perceptions of entitativity, the current study focused on expectations of similarity and behavioral consistency. It was predicted that in general, perceivers expect greater entitativity for individual than group targets. However, when explicitly provided with similar expectancies of entitativity, information processing would be similar for both individual and group targets. Two experiments supported these predictions, using recall, memory-judgment correlation, and illusory correlation measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Extensive experimental data indicates that the particle property dependence of the just-suspended agitation speed of pitched-blade turbines and high-efficiency impellers can be described with reasonable accuracy using a Zwietering power-law correlation. However, there are indications that the effect of particle size is divided into two regimes, one for particle sizes less than 1000 μm and one for larger particles. Comparison of the two impeller types indicates that the pitched-blade turbine requires somewhat higher power inputs and substantially higher torque levels to produce the same level of agitation as the high-efficiency impeller. 相似文献
993.
994.
This paper considers the recovery of a multichannel harmonic signal field corrupted by a possibly unknown homogeneous noise field. An approach is presented using the convergence-based spectra developed by Foias et al. (1990) in the random process setting. This technique has the advantage of discerning between the point and narrowband noise spectrum based on the monotonically decreasing convergence properties of a sequence of minimum variance (MV) spectra. For the proposed technique, the random field is reduced to a sequence of random processes using a set of condensing functions. An additional advantage of the proposed technique is that these condensing functions can be used to reflect a priori information and, hence, improve the effective signal-to-noise ratio (SNR). This technique uses information from all dimensions. Traditional techniques would separately apply a spectral algorithm to each dimension of the random field and thereby lose joint information from other dimensions 相似文献
995.
Neeta B. O'Mara Samina Ali Kathleen Bivens Richard A. Sherman Toros Kapoian 《Hemodialysis international. International Symposium on Home Hemodialysis》2003,7(2):130-134
Background: Low blood flow is a frequent complication of central‐vein (CV) dialysis catheters. Since thrombotic occlusion accounts for many cases of reduced blood flow, it is common practice to administer empiric thrombolytic therapy in an attempt to restore catheter patency and improve function.
Methods: We prepared tissue plasminogen activator (tPA) from 50 mg lyophilized powder, which was diluted (1 mg/mL) in sterile water for injection. A volume of 1 mL was frozen in 3 cc polystyrene syringes at −20 °C and thawed at room temperature when needed. tPA was then administered into the arterial and venous ports of the central venous catheter in a volume equal to the manufacturer's stated luminal volume and was allowed to dwell for 30 minutes.
Results: tPA was administered 62 times in 25 patients with 30 catheters (11 Tesio, 17 PermCath, 2 Shiley) for treatment of low blood flow (pump speed < 250 mL/min). Complete restoration of patency was achieved in 23 episodes (mean blood flow pre‐tPA 130 mL/min; post‐tPA 320 mL/min); partial restoration of patency was achieved in 20 episodes (mean blood flow pre‐tPA 69 mL/min; post‐tPA 233 mL/min). tPA was just as likely to be effective in patients with complete catheter occlusion (i.e., no blood flow) as it was when some initial blood flow was present. Nineteen episodes failed to respond to tPA. These episodes occurred in 13 catheters, 12 of which ultimately underwent radiologic evaluation; an extraluminal cause for low blood flow was found in all 12 catheters (6 malpositioned, 6 fibrin sheaths).
Conclusions: tPA at a dose of 1 mg/mL is effective for restoring patency in CV dialysis catheters. Failure to respond to tPA strongly suggests an extraluminal cause of catheter malfunction. 相似文献
Methods: We prepared tissue plasminogen activator (tPA) from 50 mg lyophilized powder, which was diluted (1 mg/mL) in sterile water for injection. A volume of 1 mL was frozen in 3 cc polystyrene syringes at −20 °C and thawed at room temperature when needed. tPA was then administered into the arterial and venous ports of the central venous catheter in a volume equal to the manufacturer's stated luminal volume and was allowed to dwell for 30 minutes.
Results: tPA was administered 62 times in 25 patients with 30 catheters (11 Tesio, 17 PermCath, 2 Shiley) for treatment of low blood flow (pump speed < 250 mL/min). Complete restoration of patency was achieved in 23 episodes (mean blood flow pre‐tPA 130 mL/min; post‐tPA 320 mL/min); partial restoration of patency was achieved in 20 episodes (mean blood flow pre‐tPA 69 mL/min; post‐tPA 233 mL/min). tPA was just as likely to be effective in patients with complete catheter occlusion (i.e., no blood flow) as it was when some initial blood flow was present. Nineteen episodes failed to respond to tPA. These episodes occurred in 13 catheters, 12 of which ultimately underwent radiologic evaluation; an extraluminal cause for low blood flow was found in all 12 catheters (6 malpositioned, 6 fibrin sheaths).
Conclusions: tPA at a dose of 1 mg/mL is effective for restoring patency in CV dialysis catheters. Failure to respond to tPA strongly suggests an extraluminal cause of catheter malfunction. 相似文献
996.
Dobrovolsky A.A. Lemanov V.V. Sherman A.B. Gal'perin Yu.M. Kozub V.I. 《Electronics letters》1980,16(7):243-244
Some new experimental results and a simple theoretical model of nonlinear interaction of s.a.w.s in piezoelectric crystals with electron beams are presented. 相似文献
997.
G Davis G McClure R Sherman M Hibbert M Wong R Perez 《Canadian Metallurgical Quarterly》1998,163(12):808-812
The purpose of this study was to assess the accuracy of ambulatory urodynamic monitoring compared with conventional urodynamic studies for the detection of exercise-induced urinary incontinence in the female soldier. Fifty active duty female soldiers with exercise-induced urinary incontinence and 10 asymptomatic control soldiers underwent conventional multichannel cystometry and then ambulatory monitoring during work or exercise. Ambulatory monitoring detected a greater number of abnormalities than conventional multichannel urodynamic studies in exercise-induced urinary incontinence. This greater sensitivity is valuable in formulating more effective treatment. Behavioral interventions were effective in treating exercise-induced urinary incontinence in this population. Test results normalized after behavioral intervention. It is neither cost-effective nor efficacious to require sophisticated urodynamic testing before instituting behavioral interventions. 相似文献
998.
AB Meriin VL Gabai J Yaglom VI Shifrin MY Sherman 《Canadian Metallurgical Quarterly》1998,273(11):6373-6379
Inhibition of the major cytosolic protease, proteasome, has been reported to induce programmed cell death in several cell lines, while with other lines, similar inhibition blocked apoptosis triggered by a variety of harmful treatments. To elucidate the mechanism of pro- and antiapoptotic action of proteasome inhibitors, their effects on U937 lymphoid and 293 kidney human tumor cells were tested. Treatment with peptidyl aldehyde MG132 and other proteasome inhibitors led to a steady increase in activity of c-Jun N-terminal kinase, JNK1, which is known to initiate the apoptotic program in response to certain stresses. Dose dependence of MG132-induced JNK activation was parallel with that of apoptosis. Furthermore, inhibition of the JNK signaling pathway strongly suppressed MG132-induced apoptosis. These data indicate that JNK is critical for the cell death caused by proteasome inhibitors. An antiapoptotic action of proteasome inhibitors could be revealed by a short incubation of cells with MG132 followed by its withdrawal. Under these conditions, the major heat shock protein Hsp72 accumulated in cells and caused suppression of JNK activation in response to certain stresses. Accordingly, pretreatment with MG132 reduced JNK-dependent apoptosis caused by heat shock or ethanol, but it was unable to block JNK-independent apoptosis induced by TNFalpha. Therefore, proteasome inhibitors activate JNK, which initiates an apoptotic program, and simultaneously they induce Hsp72, which suppresses JNK-dependent apoptosis. A balance between these two effects might define the fate of cells exposed to the inhibitors. 相似文献
999.
Julian N. Kanfer 《Lipids》1972,7(10):653-655
Ceramide galacturonate was synthesized from ceramide galactoside by the sequential treatment with galactose oxidase and hypoiodite
oxidation. The sole water soluble hydrolysis product was galacturonic acid. 相似文献
1000.
RW Roof MD Haskell BD Dukes N Sherman M Kinter SJ Parsons 《Canadian Metallurgical Quarterly》1998,18(12):7052-7063
p190 RhoGAP is a 190-kDa protein that stably associates with p120 RasGAP and regulates actin dynamics through members of the Rho family of small GTPases. Previous studies have indicated a direct relationship between levels of p190 tyrosine phosphorylation, the extent and kinetics of epidermal growth factor (EGF)-induced actin rearrangements, and EGF-induced cell cycle progression, suggesting that p190 links Ras-mediated mitogenic signaling with signaling through the actin cytoskeleton. Determining which tyrosine residues in p190 are phosphorylated, what factors regulate phosphorylation of these sites, and what effect tyrosine phosphorylation has on p190 function is key to understanding the role(s) that p190 may play in these processes. To begin investigating these questions, we used biochemical approaches to characterize the number and relative levels of in vivo-phosphorylated tyrosine residues on endogenous p190 from C3H10T1/2 murine fibroblasts. Only two tryptic phosphopeptides containing phosphotyrosine (p-Tyr), a major site, identified as Y1105, and a minor, unidentified site, were detected. Phosphorylation of Y1105, but not the minor site, was modulated in vivo to a greater extent by overexpression of c-Src than by the EGF receptor and was efficiently catalyzed by c-Src in vitro, indicating that Y1105 is a selective and preferential target of c-Src both in vitro and in vivo. In vitro and in vivo coprecipitation analysis using glutathione S-transferase (GST) fusion proteins containing wild-type and Y1105F variants of the p190 middle domain, variants of full-length p190 ectopically expressed in COS-7 cells, and endogenous p190 and p120 in C3H10T1/2 cells revealed that p190 could bind to p120 in the presence and absence of p190 tyrosine phosphorylation. p-Tyr-independent complexes comprised 10 to 20% of the complexes formed in the presence of p-Tyr. Mutation of Y1105 from Tyr to Phe resulted in complete loss of p-Tyr-dependent complex formation, indicating that p-Y1105 was the sole p-Tyr residue mediating binding to p120. These studies describe a specific mechanism by which c-Src can regulate p190-p120 association and also document a significant role for p-Tyr-independent means of p190-p120 binding. 相似文献