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51.
We describe a rare case of pulmonary blastoma complicated with systemic sclerosis. The serum alpha-fetoprotein level was elevated at presentation and the biopsied tumour stained positively against anti-alpha-fetoprotein antibody. The alpha-fetoprotein produced autonomously by tumour cells was of yolk-sac origin. Although the pathogenesis of pulmonary blastoma has not been clarified, we suggest that this pulmonary blastoma is a type of yolk-sac tumour.  相似文献   
52.
53.
Ozonation followed by granular activated carbon (GAC) is one of the advanced drinking water treatments. During GAC treatment, ammonia can be oxidized by ammonia-oxidizing microorganisms associated with GAC. However, there is little information on the abundance and diversity of ammonia-oxidizing microorganisms on GAC. In this study, the nitrification activity of GAC and the settlement of ammonia-oxidizing archaea (AOA) and bacteria (AOB) in GAC were monitored at a new full-scale advanced drinking water treatment plant in Japan for 1 year after plant start-up. Prechlorination was implemented at the receiving well for the first 10 months of operation to treat ammonia in raw water. During this prechlorination period, levels of both AOA and AOB associated with GAC were below the quantification limit. After prechlorination was stopped, 105 copies g-dry−1 of AOA amoA genes were detected within 3 weeks and the quantities ultimately reached 106-107 copies g-dry−1, while levels of AOB amoA genes still remained below the quantification limit. This observation indicates that AOA can settle in GAC rapidly without prechlorination. The nitrification activity of GAC increased concurrently with the settlement of AOA after prechlorination was stopped. Estimation of in situ cell-specific ammonia-oxidation activity for AOA on the assumption that only AOA and AOB determined can contribute to nitrification suggests that AOA may account for most of the ammonia-oxidation. However, further validation on AOB contribution is required.  相似文献   
54.
Novel calcium phosphate ceramics were fabricated by hot-pressing fibrous products extracted from crystallized products of calcium ultraphosphate glasses by aqueous leaching. The ceramics were dense materials with a relative density of >95%; these ceramics were composite materials that consisted of β-Ca(PO3)2 fibrous crystals with CaO–P2O5 glass, which was formed during hot pressing, as the matrix phase. These ceramics showed a high bending strength of 150–220 MPa and a low Young's modulus of 30–60 GPa. The high toughness contributed to the high strength, with fiber pull-out and crack deflection observed as the primary toughening mechanism.  相似文献   
55.
A nonwoven fabric scaffold for guided bone regeneration (GBR) consisting of siloxane-poly(lactic acid) (PLA)-vaterite hybrid material (SiPVH) was prepared by an electrospinning method. To improve the cellular compatibility of the fabric, the fibers were completely coated with hydroxyapatite (HA) by soaking in simulated body fluid. The HA-coated SiPVH nonwoven fabric contained large-sized spaces and showed the ability of releasing soluble silica and calcium species, which have previously been reported to stimulate osteogenic cells at the genetic level. A new type of GBR membrane was prepared by bonding SiPVH fabric with PLA nonwoven fabric with small-sized pores for preventing the intrusion of soft tissue. The resultant bi-layered membrane was expected to be effective not only for having an open structure for bone formation and a barrier to soft tissue, but also for enhancing bone growth by the release of ionic species.  相似文献   
56.
A risk assessment of Vibrio parahaemolyticus in bloody clams (Anadara granosa) consumed in southern Thailand was conducted. This study estimated the prevalence and concentration of pathogenic V. parahaemolyticus in bloody clams at harvest and retail stages; and during this process, methods to detect the total and pathogenic V. parahaemolyticus were investigated. Consumption of bloody clams and cooking efficiency were studied using interviews and onsite observation of consumers. A beta-Poisson dose–response model was used to estimate probability of illness applying estimation methods for the most likely parameter values presented by USFDA. Microbial and behavioral data were analyzed by developing a stochastic model and the simulation gave a mean number of times a person would get ill with V. parahaemolyticus by consuming bloody clams at 5.6 × 10− 4/person/year. Sensitivity analysis demonstrated the fraction of people who did not boil the clams properly was the primary factor in increasing risk. This study serves as an example of how a microbiological risk assessment with limited data collection and international cooperation leads to valuable local insight.  相似文献   
57.
We studied the effects of intra-third cerebroventricular administration of neuropeptide Y (NPY), peptide YY (PYY) and pancreatic polypeptide (PP) on the locomotor activity and the feeding and learning behavior of mice. NPY (0.3-10 micrograms), PYY (0.1-10 micrograms) and PP (3.0-10 micrograms) produced significant increases in locomotor activity. A significant decrease was then observed 15 min after administration of 10 micrograms of PYY. NPY, PYY and PP significantly increased food intake at 20 min and this effect continued for 2 to 4 hr at the high doses. The feeding response to PP family peptides were quite similar to that in locomotor activity with respect to dose-response, time course and peptide specificity. Learning behaviors were evaluated at three different stages of memory processing, acquisition, consolidation and retrieval, in a battery of step-down type passive avoidance tests. NPY and PYY had no effect on acquisition, but significantly improved consolidation at a dose of 0.03 and 0.3 microgram, respectively. NPY also improved retrieval at a dose of 0.03 microgram. The ranking order of potency in stimulating feeding and locomotor activity was PYY > NPY > PP, and in improving memory consolidation NPY > PYY > PP. These observations suggest that NPY and PYY influence different neural substrates in the brain involved in feeding and learning.  相似文献   
58.
Juvenile arthritis (JA) is a term that covers a number of different disease entities, of which only three present with significant Human Leukocyte Antigen (HLA) associations. (1) Pauciarticular JA with late onset and a strong male proponderance is associated with HLA-B27 and represents the group of juvenile spondyloarthropathies related to adult ankylosing spondylitis. (2) Early onset pauciarticular JA with a preponderance of females and a frequent occurance of chronic iridocyclitis and the frequent presence of anti-nuclear antibodies is associated with alleles from three different regions of the HLA system: HLA-A2, which shows a very strong correlation with early age of onset; DR8, DR11 and DR12 as well as DQA1*0401, *0501, *0601 and finally DPB1*0201. These alleles show no linkage disequilibrium in the control population. (3) Rheumatoid factor positive polyarticular JA is associated, as is adult rheumatoid arthritis, with DR4. Concerning the possible mechanisms of the immunopathogenesis, it is speculated that the normal function of HLA molecules, namely the presentation of antigenic peptides, plays a major role. Data collected on HLA associations in early onset pauciarticular JA have been interpreted as indicating that alleles of the DQA1 locus (*0401, *0501, *0601) are probably responsible for presenting the hypothetical arthritogenic peptides. It is speculated that the pathogenic process includes the presentation of HLA-A2 or HLA-DPB1*0201 derived peptides presented by DQ molecules. It is clearly stated that typing for HLA alleles has very little or no importance for clinical diagnosis and prognosis.  相似文献   
59.
This study was designed to investigate the effects of endomorphin 1 and 2, recently identified mu-opioid receptor selective peptides, on food intake and anxiety in non-food-deprived mice. The intracerebroventricular (i.c.v.) injection of either endomorphin 1 or 2 (0.03-30 nmol) increased food intake in a dose-related manner. A significant increase was observed 20 min after i.c.v. injection of endomorphin 1 or 2 and continued for 4 h. In the elevated plus maze test, the i.c.v. injection of endomorphin 1 (30 nmol) significantly decreased the normal preference for the closed arms. These results suggest that endomorphin produces orexigenic and anxiolytic effects, and that the mu-opioid receptor contributes to the regulation of feeding and anxiety in mice.  相似文献   
60.
Insulin induces the translocation of vesicles containing the glucose transporter GLUT4 from an intracellular compartment to the plasma membrane in adipocytes. SNARE proteins have been implicated in the docking and fusion of these vesicles with the cell membrane. The role of Munc18c, previously identified as an n-Sec1/Munc18 homolog in 3T3-L1 adipocytes, in insulin-regulated GLUT4 trafficking has now been investigated in 3T3-L1 adipocytes. In these cells, Munc18c was predominantly associated with syntaxin4, although it bound both syntaxin2 and syntaxin4 to similar extents in vitro. In addition, SNAP-23, an adipocyte homolog of SNAP-25, associated with both syntaxins 2 and 4 in 3T3-L1 adipocytes. Overexpression of Munc18c in 3T3-L1 adipocytes by adenovirus-mediated gene transfer resulted in inhibition of insulin-stimulated glucose transport in a virus dose-dependent manner (maximal effect, approximately 50%) as well as in inhibition of sorbitol-induced glucose transport (by approximately 35%), which is mediated by a pathway different from that used by insulin. In contrast, Munc18b, which is also expressed in adipocytes but which did not bind to syntaxin4, had no effect on glucose transport. Furthermore, overexpression of Munc18c resulted in inhibition of insulin-induced translocation of GLUT4, but not of that of GLUT1, to the plasma membrane. These results suggest that Munc18c is involved in the insulin-dependent trafficking of GLUT4 from the intracellular storage compartment to the plasma membrane in 3T3-L1 adipocytes by modulating the formation of a SNARE complex that includes syntaxin4.  相似文献   
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