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991.
Materials on morbidity in Omsk hemorrhagic fever at the period of 1988-1992 in the districts of the Novosibirsk region are presented. Cases of the disease were registered mainly in September-October (83.3% of cases). Transmission of the disease by contact played the leading role in the epidemiology of Omsk hemorrhagic fever. The disease took the course of medium severity with faintly pronounced hemorrhagic syndrome.  相似文献   
992.
The increased expression of epidermal growth factor receptor induced by tumor necrosis factor alpha renders pancreatic cancer cells more susceptible to antibody-dependent cellular cytotoxicity by a mAb specific for this receptor. Laboratory studies with athymic mice bearing xenografts of human pancreatic cancer cells demonstrated a cytokine-induced ability of the mAb to cause significant tumor regression. In a phase I/II clinical trial, 26 patients with unresectable pancreatic cancer were enrolled into three cohorts receiving variable amounts of the antibody together with a constant amount of tumor necrosis factor alpha. With increasing doses of antibody, the growth of the primary tumor was significantly inhibited. This was reflected by a longer median survival, with one complete remission lasting for 3 years obtained with the highest dose of antibody employed. Thus, a combination of the cytokine, tumor necrosis factor alpha, with a mAb to the epidermal growth factor receptor offers a potentially useful approach for the treatment of pancreatic cancer.  相似文献   
993.
OBJECTIVE: To evaluate psychiatric disorders and impairment in school-age and adolescent children of opiate-dependent patients. METHOD: One hundred fourteen children, aged 6 to 17 years, of 69 white methadone maintenance patients with (n = 30) and without (n = 39) major depression were evaluated for DSM-III-R diagnoses by the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Epidemiologic version and best estimate, and by measures of functioning (Children's Global Assessment Scale, Social Adjustment Inventory for Children and Adolescents, WISC, Peabody Picture Vocabulary Test), and compared with children of historical controls without substance abuse history. RESULTS: Sons of opiate addicts with major depression were at increased risk for conduct disorder and global, social, and intellectual impairment compared with sons of opiate addicts without major depression and/or sons of controls with neither drug dependence nor depression. Sons of opiate addicts without major depression differed little from controls. Daughters of opiate addicts did not differ from controls in rates of disorders but had poorer social adjustment and nonverbal intelligence. CONCLUSIONS: Children of opiate-dependent patients, particularly sons of addicts with depression, may be at risk for a developmental path toward antisocial personality and poor social and intellectual functioning. Treatment settings such as methadone maintenance might afford an opportunity for primary and secondary prevention, both through early detection of childhood disorders and treatment of parental drug dependence and psychopathology.  相似文献   
994.
The study of human papillomavirus (HPV)-induced carcinogenesis uses multiple in vivo mouse models, one of which relies on the cytokeratin 14 gene promoter to drive the expression of all HPV early oncogenes. This study aimed to determine the HPV16 variant and sublineage present in the K14HPV16 mouse model. This information can be considered of great importance to further enhance this K14HPV16 model as an essential research tool and optimize its use for basic and translational studies. Our study evaluated HPV DNA from 17 samples isolated from 4 animals, both wild-type (n = 2) and HPV16-transgenic mice (n = 2). Total DNA was extracted from tissues and the detection of HPV16 was performed using a qPCR multiplex. HPV16-positive samples were subsequently whole-genome sequenced by next-generation sequencing techniques. The phylogenetic positioning clearly shows K14HPV16 samples clustering together in the sub-lineage A1 (NC001526.4). A comparative genome analysis of K14HPV16 samples revealed three mutations to the human papillomaviruses type 16 sublineage A1 representative strain. Knowledge of the HPV 16 variant is fundamental, and these findings will allow the rational use of this animal model to explore the role of the A1 sublineage in HPV-driven cancer.  相似文献   
995.
Pitanga fruit stands out for its exotic flavour and antioxidant properties. The objective of this work was to evaluate changes in the physical, chemical and biochemical variables of red pitanga variety, in four stages of development (green, yellow, orange and red) and associate them to the cell wall break down. Analysis of pH, titratable acidity, soluble solids, firmness, soluble pectin, pectinamethylesterase (PME), polygalacturonase (PG), cell wall swelling and microstructure were performed. pH and levels of soluble solids and soluble pectin increased, in addition to the cell wall swelling and reduction of firmness, throughout the development of pitanga. From the SEM, it was possible to observe the degradation of the fruit cell wall during ripening, suggesting mainly the degradation of pectic polysaccharides, verified by the solubilisation of these substances. PG and PME enzymes were not active, which suggests that other enzymes may be associated with the cell wall break down.  相似文献   
996.
Bulletin of Engineering Geology and the Environment - This study addresses the influence of climate seasonal variations on the slide safety factor on a granite residual soil slope based on the...  相似文献   
997.
Journal of Chemical Ecology - Olfactory cues constitute one of the most important plant-pollinator communication channels. Specific chemical components can be associated with specific pollinator...  相似文献   
998.
999.
The red clay ceramic industry is associated with several environmental damages, from the extraction of natural resources as raw materials to the generation of high amounts of waste. This study proposed the incorporation of the ceramic bricks waste (chamotte) in ceramic mixtures for the production of clay bricks. In order to define the greater content of chamotte, which can be added maintaining the technical qualities required for the product, the experimental design of mixtures was used, with the production of bricks containing the chamotte and two other clayey materials. The compositions were subjected to firing at 850, 950, and 1050°C. The properties of firing linear shrinkage, apparent specific mass, water absorption, apparent porosity, and axial compressive strength were evaluated. It was observed that chamotte (C) contributed to the improvement of some of these properties, such as linear shrinkage. Overlapping the response surfaces obtained in the statistical analysis, the optimal chamotte (C) content was determined for each firing temperature. It was concluded that the incorporation of up to 30% chamotte (C) is technically feasible considering the evaluated temperature range. In this way, there is a product that adds both sustainability and technical performance to the ceramic industry.  相似文献   
1000.
This work deals with the preparation of freeze-cast scaffolds using sol-gel derived 58S bioactive glass and a hypoeutectic naphthalene-camphor mixture as the starting powder and freezing vehicle, respectively. After the freeze-casting step, samples were air sintered at 1250?°C for 2?h, which led to the crystallization of 58S. The obtained scaffolds were subsequently infiltrated with poly(ε-caprolactone) (PCL), a biodegradable polymer with potential application for bone tissue repair. The prepared materials were examined by helium pycnometry, laser granulometry, scanning electron microscopy (SEM), Archimedes tests, X-ray microtomography (micro-CT), Fourier transform infrared spectroscopy (FTIR), N2 adsorption, X-ray diffraction (XRD), and uniaxial compression tests. Samples cytotoxicity was evaluated by (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) tetrazolium reduction (MTT) and LIVE/DEAD assays. Their biocompatibility was also examined after soaking in a simulated body fluid (SBF) solution at 37?°C for up to 14 days. It was observed that the infiltration of PCL into the 58S scaffolds greatly increased their mechanical stability. Moreover, it was shown that these composites displayed a high cell viability (above 70%), which reveals that they did not interfere in the production of osteoblast cells. A hydroxyapatite coating was observed on the samples surface upon soaking in SBF, reinforcing that they are biocompatible materials. As far as we know, this is the first time that freeze-cast scaffolds were obtained using sol-gel derived 58S particles and a naphthalene-camphor mixture. Besides, as the infiltration of PCL into freeze-cast bioactive glass scaffolds improved their mechanical stability without impairing their bioactivity, this is a promising approach to prepare samples for load-bearing applications in bone tissue engineering.  相似文献   
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