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11.
OBJECTIVE: We studied 22 dogs to examine the effect of basic fibroblast growth factor (bFGF) alone, in comparison with omental or muscular wrapping on airway healing in a tracheal autotransplantation model. SUMMARY BACKGROUND DATA: Basic fibroblast growth factor is one of the most potent promoters of angiogenesis and has an ability to enhance blood supply to the ischemic airway. Topical administration of a fibrin glue enriched with 5 microg/cm2 bFGF, determined as a proportion of surface area of the tracheal grafts, improved revascularization of orthotopic canine tracheal autografts in a previous study. METHODS: All animals received orthotopic tracheal transplantation using 6-ring autografts that occupied a distal part of the thoracic trachea. Twenty-two animals were classified randomly into the following four groups: no treatment (Group G1, n = 4), muscular wrapping (Group G2, n = 4), omental wrapping (Group G3, n = 4), and topical administration of fibrin glue enriched with 5 microg/cm2 bFGF (Group G4, n = 10). Autografts were harvested 60 days after transplantation and assessed by the percent patency and histology. RESULTS: Devascularized tracheal autografts could not maintain their structural integrity without other treatments (Group G1). In contrast, more than half of all autografts receiving treatments remained viable, as demonstrated by gross and histologic findings (Groups G2, G3, and G4). Treatments with bFGF and omentum showed significantly better graft viability than no treatment. However, there was no statistical difference in the viability of tracheal autografts among the three treatment groups. In terms of the time performance ratio, bFGF was the best treatment for the devascularized autografts. CONCLUSIONS: Topical administration of bFGF was superior to the omental or muscular wrapping in terms of the time performance ratio. Clinical trials will be necessary to determine whether these findings are applicable to humans.  相似文献   
12.
A novel formulation of radiation from a localized line source placed in two-dimensional photonic crystals consisting of layered periodic arrays of parallel circular cylinders is presented. The method employs the spectral domain approach. The spectral response of the photonic crystals to the line source excitation is calculated using the lattice sums, the T-matrix of a circular cylinder, and the generalized reflection and transmission matrices of the layered system. The far-zone radiated field is obtained using the conventional asymptotic method to the spectral response. The radiation patterns of the localized line source sandwiched by two photonic crystals are numerically studied.  相似文献   
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The rutin content of buckwheat products was compared to the rutin content in their raw materials, in order to evaluate their value for producing functional foods. There is much less rutin in noodles (78 mg/kg, d.w.b. – dry weight basis), than in the dark buckwheat flour (218 mg/kg, d.w.b.) from which they are produced. One of the possible explanations is the presence of the rutin degrading enzyme. In raw (uncooked) groats there is 230 mg/kg (d.w.b.) of rutin and in precooked groats, 88 mg/kg (d.w.b.). In buckwheat beer and vinegar there is a negligible content of rutin. Buckwheat leaf flour contains about 2700 mg/kg (d.w.b.) rutin, and is thus a suitable material for enriching functional foods, giving it the potential for preventive nutrition.  相似文献   
14.
For a number of years titanium osteointegrated implants have represented a major step forward in dentistry, plastic and maxillofacial surgery, providing a lively stimulus to research both in their application and in the experimental field. The study of osteointegration has led to a more detailed knowledge of bone remodelling regulation mechanisms and the biological mediators involved. In this review the authors examine the role played by cytokines in the homeostasis of bone tissue, paying special reference to the phase of osteoclast activation and its possible effects on peri-implant bone resorption. The authors focus in particular on the effects of interleukin-6 (IL-6) as an important osteotropic factor and a hypothetical target on which to act in order to modulate its effects for therapeutical purposes.  相似文献   
15.
A two-dimensional inverse filter has been implemented using floating-gate tapped c.c.d.s. The least-mean-square criterion was applied to obtain tap gains. Filter responses in both frequency and time domains were examined. Results confirm that the two-dimensional inverse filter can effectively eliminate both intersymbol and crosschannel interferences.  相似文献   
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The fractional uptake of intact monoclonal antibodies by tumors is relatively low. Various methods to alter the molecular structure have been used to augment tumor uptake. These chemical manipulations, however, may alter the specificity of antibody binding. METHODS: Comparative studies of biodistribution, radioimmunoimaging and macroautoradiography in LC-6 xenografted mice were conducted with the 125I-labeled intact and N-terminal deglycosylated monoclonal antibodies to evaluate the effect on deglycosylation on antibody binding. RESULTS: The removal of N-glycosyl residues from this monoclonal antibody significantly enhanced specific localization of the radioactivity to the tumor, especially to its necrotic fraction. Nonspecific accumulation of radioactivity to the necrotic fraction of the tumor was excluded by biodistribution studies demonstrating selective accumulation of 125I-labeled monoclonal antibody after coadministration of 125I-monoclonal antibody (intact or N-deglycosylated) with 131I-labeled control IgM. CONCLUSION: The lung cancer-associated human monoclonal antibody HB4C5, which recognizes histone H2B as the antigen, accumulates specifically to the necrotic fraction of tumor. The uptake is enhanced by removal of N-terminal glycosyl residues from the antigen-binding site of the light chain.  相似文献   
19.
Materials such as expanded polytetrafluoroethylene and glutaraldehyde‐fixed bovine pericardium are currently used for cardiac tissue regeneration. However, patches made from these materials remain permanently without being absorbed by the body and must be replaced overtime because of degeneration or lack of growth. To improve the long‐term outcomes for cardiac tissue regeneration, biocompatible and biodegradable materials must be used. In this study, we used two biocompatible polymers, silk fibroin (SF), which is biodegradable and segmented polyurethane, to prepare nonwoven sheets that were then insolubilized by water vapor or methanol treatment. The tensile stress increased significantly on adding segmented polyurethane to pure SF and the water vapor processed sheets showed higher extension on strain than the methanol‐processed sheets. The different insolubilization treatments also resulted in different SF structures. Our results show that it is possible to obtain the physical properties required for cardiac tissue repair patch by varying the insolubilization treatment. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45560.  相似文献   
20.
Comparing polyaluminum chloride and ferric chloride for antimony removal   总被引:9,自引:0,他引:9  
Kang M  Kamei T  Magara Y 《Water research》2003,37(17):4171-4179
Antimony has been one of the contaminants required to be regulated, however, only limited information has been collected to date regarding antimony removal by polyaluminium chloride (PACl) and ferric chloride (FC). Accordingly, the possible use of coagulation by PACl or FC for antimony removal was investigated. Jar tests were used to determine the effects of solution pH, coagulant dosage, and pre-chlorination on the removal of various antimony species. Although high-efficiency antimony removal by aluminum coagulation has been expected because antimony is similar to arsenic in that both antimony and arsenic are a kind of metalloid in group V of the periodic chart, this study indicated: (1) removal density (arsenic or antimony removed per mg coagulant) for antimony by PACl was about one forty-fifth as low as observed for As(V); (2) although the removal of both Sb(III) and Sb(V) by coagulation with FC was much higher than that of PACl, a high coagulant dose of 10.5mg of FeL(-1) at optimal pH of 5.0 was still not sufficient to meet the standard antimony level of 2 microg as SbL(-1) for drinking water when around 6 microg as SbL(-1) were initially present. Consequently, investigation of a more appropriate treatment process is necessary to develop economical Sb reduction; (3) although previous studies concluded that As(V) is more effectively removed than As(III), this study showed that the removal of Sb(III) by coagulation with FC was much more pronounced than that of Sb(V); (4) oxidation of Sb(III) with chlorine decreased the ability of FC to remove antimony. Accordingly, natural water containing Sb(III) under anoxic condition should be coagulated without pre-oxidation.  相似文献   
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