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Blends of poly(N‐isopropylacrylamide) (PNIPAM) and an ethylene/vinyl alcohol copolymer (EVAL) were obtained through casting from dimethyl sulfoxide (DMSO) solutions and phase inversion in 50/50 DMSO/H2O solutions. The miscibility and morphology of the PNIPAM/EVAL blends were investigated with thermal and morphological analysis. Differential scanning calorimetry indicated that the crystallinity of EVAL decreased with increasing PNIPAM content and that the blends cast from DMSO/H2O solutions were miscible in the melt state. Measurements of the melting point depression allowed the determination of the interaction energy density (B) and Flory–Huggins interaction parameter (χ12) with the Nishi–Wang equation. The negative B and χ12 values obtained were examined in terms of the specific intermolecular interactions between the polymers. Scanning electron micrographs revealed that blends obtained by the casting method led to dense membranes, whereas the phase‐inversion method rendered typical macroporous membranes. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 501–505, 2004  相似文献   
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Antimicrobial photodynamic therapy (aPDT) is increasingly being explored for treatment of periodontitis. Here, we investigated the effect of aPDT on human dental plaque bacteria in suspensions and biofilms in vitro using methylene blue (MB)-loaded poly(lactic-co-glycolic) (PLGA) nanoparticles (MB-NP) and red light at 660 nm. The effect of MB-NP-based aPDT was also evaluated in a clinical pilot study with 10 adult human subjects with chronic periodontitis. Dental plaque samples from human subjects were exposed to aPDT—in planktonic and biofilm phases—with MB or MB-NP (25 µg/mL) at 20 J/cm2 in vitro. Patients were treated either with ultrasonic scaling and scaling and root planing (US + SRP) or ultrasonic scaling + SRP + aPDT with MB-NP (25 µg/mL and 20 J/cm2) in a split-mouth design. In biofilms, MB-NP eliminated approximately 25% more bacteria than free MB. The clinical study demonstrated the safety of aPDT. Both groups showed similar improvements of clinical parameters one month following treatments. However, at three months ultrasonic SRP + aPDT showed a greater effect (28.82%) on gingival bleeding index (GBI) compared to ultrasonic SRP. The utilization of PLGA nanoparticles encapsulated with MB may be a promising adjunct in antimicrobial periodontal treatment.  相似文献   
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The autonomic nervous system (ANS) plays a crucial role both in acute and chronic psychological stress eliciting changes in many local and systemic physiological and biochemical processes. Salivary secretion is also regulated by ANS. In this study, we explored salivary proteome changes produced in thirty-eight University students by a test stress, which simulated an oral exam. Students underwent a relaxation phase followed by the stress test during which an electrocardiogram was recorded. To evaluate the effect of an olfactory stimulus, half of the students were exposed to a pleasant odor diffused in the room throughout the whole session. Saliva samples were collected after the relaxation phase (T0) and the stress test (T1). State anxiety was also evaluated at T0 and T1. Salivary proteins were separated by two-dimensional electrophoresis, and patterns at different times were compared. Spots differentially expressed were trypsin digested and identified by mass spectrometry. Western blot analysis was used to validate proteomic results. Anxiety scores and heart rate changes indicated that the fake exam induced anxiety. Significant changes of α-amylase, polymeric immunoglobulin receptor (PIGR), and immunoglobulin α chain (IGHA) secretion were observed after the stress test was performed in the two conditions. Moreover, the presence of pleasant odor reduced the acute social stress affecting salivary proteome changes. Therefore, saliva proteomic analysis was a useful approach to evaluate the rapid responses associated to an acute stress test also highlighting known biomarkers.  相似文献   
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Parathyroid tumors are rare endocrine neoplasms affecting 0.1–0.3% of the general population, including benign parathyroid adenomas (PAs; about 98% of cases), intermediate atypical parathyroid adenomas (aPAs; 1.2–1.3% of cases) and malignant metastatic parathyroid carcinomas (PCs; less than 1% of cases). These tumors are characterized by a variable spectrum of clinical phenotypes and an elevated cellular, histological and molecular heterogeneity that make it difficult to pre-operatively distinguish PAs, aPAs and PCs. Thorough knowledge of genetic, epigenetic, and molecular signatures, which characterize different parathyroid tumor subtypes and drive different tumorigeneses, is a key step to identify potential diagnostic biomarkers able to distinguish among different parathyroid neoplastic types, as well as provide novel therapeutic targets and strategies for these rare neoplasms, which are still a clinical and therapeutic challenge. Here, we review the current knowledge on gene mutations and epigenetic changes that have been associated with the development of different clinical types of parathyroid tumors, both in familial and sporadic forms of these endocrine neoplasms.  相似文献   
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The C-terminal aminoacidic sequence from NPM1-mutated protein, absent in normal human tissues, may serve as a leukemia-specific antigen and can be considered an ideal target for NPM1-mutated acute myeloid leukemia (AML) immunotherapy. Different in silico instruments and in vitro/ex vivo immunological platforms have identified the most immunogenic epitopes from NPM1-mutated protein. Spontaneous development of endogenous NPM1-mutated-specific cytotoxic T cells has been observed in patients, potentially contributing to remission maintenance and prolonged survival. Genetically engineered T cells, namely CAR-T or TCR-transduced T cells, directed against NPM1-mutated peptides bound to HLA could prospectively represent a promising therapeutic approach. Although either adoptive or vaccine-based immunotherapies are unlikely to be highly effective in patients with full-blown leukemia, these strategies, potentially in combination with immune-checkpoint inhibitors, could be promising in maintaining remission or preemptively eradicating persistent measurable residual disease, mainly in patients ineligible for allogeneic hematopoietic stem cell transplant (HSCT). Alternatively, neoantigen-specific donor lymphocyte infusion derived from healthy donors and targeting NPM1-mutated protein to selectively elicit graft-versus-leukemia effect may represent an attractive option in subjects experiencing post-HSCT relapse. Future studies are warranted to further investigate dynamics of NPM1-mutated-specific immunity and explore whether novel individualized immunotherapies may have potential clinical utility in NPM1-mutated AML patients.  相似文献   
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Nine multiparous Holstein cows were used in three 3 × 3 Latin squares to investigate the effects of feeding unheated and micronised flaxseed on milk yield and milk fatty acid composition. Three diets were formulated to meet the nutrient requirement of dairy cows in early lactation: a control diet with no added flaxseed (NFS), an unheated flaxseed diet (UFS) and a micronised flaxseed diet (MFS). The level of flaxseed in UFS and MFS was 70 g kg?1 of the diet dry matter (DM). Feeding flaxseed to dairy cows had no effect on DM intake or milk yield. However, energy‐corrected milk was higher (P < 0.05) for cows fed MFS than for those fed UFS or NFS. Supplemental flaxseed reduced (P < 0.05) the milk fat percentage without affecting the concentration of milk protein or milk lactose. However, the yield of milk components was not affected by feeding flaxseed. The concentrations of short‐chain (C4:0 to C12:0) and medium‐chain (C14:0 to C17:0) fatty acids were decreased (P < 0.05) while those of long‐chain fatty acids (C18:0 to C18:3) were increased (P < 0.05) in the milk of cows fed UFS and MFS compared with cows fed NSF. Feeding flaxseed to dairy cows can alter the milk fatty acid composition, but only minor effects on milk fatty acid composition can be expected by feeding micronised versus unheated flaxseed. Copyright © 2003 Society of Chemical Industry  相似文献   
18.
A trustable and accurate ground truth is a key requirement for benchmarking self-localization and mapping algorithms; on the other hand, collection of ground truth is a complex and daunting task, and its validation is a challenging issue. In this paper we propose two techniques for indoor ground truth collection, developed in the framework of the European project Rawseeds, which are mutually independent and also independent on the sensors onboard the robot. These techniques are based, respectively, on a network of fixed cameras, and on a network of fixed laser scanners. We show how these systems are implemented and deployed, and, most importantly, we evaluate their performance; moreover, we investigate the possible fusion of their outputs.  相似文献   
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