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31.
32.
We successfully performed a laparoscopy-assisted radical nephrectomy for renal cell carcinoma in 2 patients on long-term hemodialysis. Both tumors were incidentally discovered on screening by abdominal CT scanning. There were no complications during the operation or in the postoperative period, and both patients resumed normal activities by the fifth postoperative day. A laparoscopic-assisted radical nephrectomy may be useful for the treatment of renal cell carcinoma in hemodialysis patients.  相似文献   
33.
We observed in vitro experiment that lead increased osmotic resistance of normal human erythrocytes and decreased mean corpuscular volume and intracellular potassium. Though the mechanism of the increased osmotic resistance of erythrocytes caused by lead has not yet been completely clarified, the following hypothesis could be accepted. Lead causes leakage of water from erythrocytes, which means that more water can enter the cell before hemolysis occurs. But there has been no report of direct measurement of the intracellular water content of erythrocytes treated with lead. This paper tried to clarify the relationship between intracellular water and osmotic resistance of lead treated erythrocytes in vitro experiment. The results were: 0.05 mumol/ml of lead increases osmotic resistance, trapped water content and plasma water content of normal human blood and decreases intracellular water content after incubation for 2 hours at 37 degrees C.  相似文献   
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Erdheim-Chester disease is a rare and distinctive lipid granulomatosis with characteristic pattern of radiographic changes in bone. The characteristic radiographic finding is an unusual symmetrical sclerosis at the diametaphyseal portions of many long bones. This study demonstrates a case of Erdheim-Chester disease and mainly documents radiographic findings.  相似文献   
36.
The “linearizing method” is a method used to predict the stress/strain relation of fabrics under biaxial extension in the warp and weft directions. The stress/strain relation is firstly linearized by using a transformed strain such as ei = ?i n where ei is the transformed strain (i =1, 2), ?i the strain, and n a constant, and the stress Fi is then expressed by a linear equation in ei. The elastic parameters are determined by strip–biaxial–extension experiments in the warp and weft directions. This method was proposed by Kawabata in 1985 without sufficient examination of its validity. In this paper, the validity of the method is inspected by biaxial–extension experiments for various kinds of fabric. It is concluded that the linearizing method has sufficient capacity to enable the biaxial–extension behaviour of the fabric to be estimated with considerable accuracy. For the case when the stress/strain relation is linearized in two zones of strain, the double–zone linearization is presented here to improve the accuracy of prediction and to expand the validity of this method over a wider range of strains.  相似文献   
37.
A new approach to creep cavitation damage is developed by combining the basic features of continuum damage mechanics and mechanism-based cavitation models. Based on a polycrystal microstructures simulated by Voronoi tessellation, an anisotropic continuum damage variable is defined, and its evolution is given by applying the mechanism-based equations of cavity nucleation and growth to each grain boundary. Macroscopic creep deformation coupled with the damage variable is calculated by damage mechanics equations. The proposed method has been applied to investigate the damage evolution under uniaxial tension and reversed shear loading conditions.  相似文献   
38.
The nitroimidazole-related hypoxic radiosensitizer, pimonidazole (Pmz) was encapsulated in liposome composed of dipalmitoylphosphatidylcholine, cholesterol and dipalmitoylphosphatidylglycerol (molar ratio = 1:1:0.2; diameter = 112.9 nm), and the radiosensitization was evaluated in human melanoma cells HMV-II. Cell proliferation was examined by WST-8 assay after X-ray irradiation in the presence of liposomal Pmz or free-Pmz under hypoxic conditions. On 7th day after X-ray irradiation of 5 Gy, cell proliferation decreased more markedly in the administration of liposomal Pmz than free-Pmz at equivalent Pmz doses. Chromatin fragmentation or nuclear condensation was observed in liposomal Pmz-treated HMV-II cells. Radiosensitization was enhanced dose-dependently along with Pmz amounts of 250-2000 microM contained in liposomal Pmz. Intracellular uptake was more abundant for liposomal Pmz for 60-240 min than for free-Pmz. Thus liposomal Pmz has a potential to overcome radiation resistance in hypoxia, owing to enhanced intracellular uptake by melanoma cells.  相似文献   
39.
To determine which types of voltage-dependent Ca2+ channels mediate tachykinin release in the isolated rabbit iris sphincter muscle, we examined the effects of several Ca2+ channel modulators on contractions induced by either an elevation of the extracellular KCl concentration or application of the Na+ channel activator veratridine. Contractions caused by either 45.9 mM KCl or veratridine (10 microM) were inhibited by spantide (10 microM), a tachykinin receptor antagonist, and capsaicin (10 microM), a tachykinin-depleting agent, but were not changed by atropine. Nicardipine, an L-type Ca2+ channel blocker, inhibited contractions induced by KCl and veratridine in a concentration-dependent manner. omega-Conotoxin GVIA (1 microM), an N-type Ca2+ channel blocker, inhibited only contractions induced by lower concentrations of KCl, both when applied alone and when combined with nicardipine. Bay K 8644, an L-type Ca2+ channel activator, caused a spantide- and nicardipine-sensitive contraction in muscles partially depolarized with 15.9 mM KCl, and enhanced contractions induced by 15.9 mM KCl and veratridine (2 microM). omega-Agatoxin IVA (0.3 microM), a P-type voltage-dependent Ca2+ channel blocker, did not affect contractions induced by either KCl or veratridine. Contractions induced by exogenous substance P were not modified by any of the Ca2+ channel blockers or by Bay K 8644. These results suggest that, in the rabbit iris sphincter muscle. L- and N-type voltage-dependent Ca2+ channels are involved in neurotransmitter release from tachykininergic nerves elicited by high KCl and by veratridine.  相似文献   
40.
Topographically distinct populations of radial glial cells in the diencephalon and mesencephalon of neonatal rats and hamsters were transcellularly labeled with wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) and with the lipophilic tracer DiI. A comparison of the histological distribution of the two tracers is suggestive of two different mechanisms of transcellular labeling. Intraocular injections of WGA-HRP resulted in the uptake of exogenously applied WGA-HRP by retinal ganglion cells, followed by anterograde axonal transport and exocytosis within the optic target nuclei. In addition to the transneuronal labeling, which is typical of such injections, we observed the transcellular labeling of the processes and somata of radial glial cells that were topographically associated with the terminal fields of the labeled axons. Similar transcellular labeling of radial glial cells associated with the axon terminal fields of the colliculogeniculate projection to the medial geniculate nucleus was observed following injections of WGA-HRP in the inferior colliculus. The transcellular labeling within the radial glial cells was discontinuous and somatopetally concentrated, indicating the existence of a retrograde active transport mechanism within the radial glial processes subsequent to its uptake following release of tracer from axons. This type of labeling can be referred to as transcellular retrograde glioplasmic transport. In contrast, DiI was used as a tracer through its capacity to diffuse within the plasmalemma. Topographically distinct populations of radial glial cells were transcellularly labeled following placements of DiI in the retina, inferior colliculus, or dorsal thalamus of fixed brains. The radial processes of labeled radial glial cells consistently extended into regions that also contained labeled axons. It is likely that the transcellular radial glial labeling with DiI occurred via transmembranous diffusion. These data indicate that a close structural and functional relation exists between axons and glial cells in the developing brain.  相似文献   
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