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91.
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Polyelectrolyte polyacrylic acid (PAA), used in the chemical modification of titanium dioxide (TiO(2)) nanoparticles, allows TiO(2) nanoparticles to remain in suspension at neutral pH. The anti-17beta-estradiol (E2) antibody was immobilized on PAA-modified TiO(2) (PAA-TiO(2)) nanoparticles via covalent bonding between the carboxylic acid of PAA and the amino group of the antibody. The anti-E2-antibody-immobilized TiO(2) (E2Ab-PAA-TiO(2)) nanoparticles can form a suspension at neutral pH, with a particle size of less than 100 nm. The E2-PAA-TiO(2) nanoparticles caused the photocatalytic degradation of a typical TiO(2) substrate, methylene blue. The anti-E2 antibody immobilized on the TiO(2) surface recognized and bound E2 in the solution, thereby improving the efficiency of E2 degradation compared with that of PAA-TiO(2) nanoparticles. These results demonstrate that the E2Ab-PAA-TiO(2) nanoparticles developed in this study can be used in water treatment technology. Furthermore, this strategy of immobilizing proteins on nanoscale TiO(2) particles creates new applications not only in the treatment of environmental waste, but also in medical and public sanitation processes.  相似文献   
93.
Infectious bovine rhinotracheitis (IBR) virus antigen was demonstrated by the immunoperoxidase method in tissues of two aborted bovine fetuses, which had been stored for 25 years after fixing in formalin and embedding in paraffin. Necrotic foci were detected in the liver, kidney, adrenal gland, and thymus of the fetuses. Coincidenting with the distribution of the necrotic foci, IBR virus antigen was demonstrated by immunostaining. The present study proved the immunoperoxidase method in one of useful techniques to demonstrate IBR virus antigen in tissue sections from preserved paraffin blocks.  相似文献   
94.
Inhibitors of DNA topoisomerases I and II induced arrest in cell division in normal human fibroblasts depending on cell divisions. Arrested cells showed morphology similar to those of normally senesced cells and strongly induced senescence-associated beta-galactosidase. In these cells, p16ink4a was upregulated, whereas p21waf1 or p53 was not altered. Upon removal of the inhibitors, the cells resumed growth but their cumulative population doublings were reduced dose dependently. Accelerated telomere shortening was not observed in the arrested cells. These results suggest that DNA topoisomerase inhibitors are efficient and reversible inducers of premature senescence in normal human cells.  相似文献   
95.
A 64-year-old woman presented with cardiomegaly, Sweet's syndrome, and refractory anemia (RA), and died of sudden cardiac arrest. The autopsy revealed a perivascular and myocardial infiltration by neutrophils, which could be responsible for the cardiomegaly and probably had caused disturbances in the conduction system leading to sudden cardiac arrest. Myocardial infiltration by functionally defective neutrophils can develop in a patient with myelodysplastic syndrome (MDS) without peripheral neutrophilia or leukemic blood picture and needs a special diagnostic and therapeutic consideration.  相似文献   
96.
Injection of kappa-agonist dynorphins and non-peptide kappa-agonists into the hippocampus induces a reduction in blood pressure. It has been postulated that kappa-opioid agonists and kappa-receptors are important in one mechanism of antihypertension and might have clinical potential for the treatment of hypertension. We have investigated whether chronic treatment with U-50488H and U-62066E, two non-peptide kappa-agonists, effects brain kappa 1- or kappa 2-receptor numbers or affinities in areas that might correlate with changes in blood pressure. kappa 1- and kappa 2-Opioid receptor affinities and densities were determined in cortex, hippocampus, hypothalamus, midbrain and pons after 14 days subcutaneous infusion of two non-peptide kappa-agonists, U-50488H and U-62066E, 9.6 mg kg day-1, by means of osmotic minipumps, to spontaneously hypertensive rats (SHR) and to Wistar-Kyoto (WKY) rats. This infusion significantly reduced blood pressure. Brains were removed within 48 h of the end of drug infusion and kappa-receptor binding studies were performed on homogenates from each brain area using [3H]U-69593 to assay kappa 1-receptors and [3H]bremazocine to assay kappa 2-receptors. U-62066E treatment seemed to cause a slight decrease in the number of [3H]bremazocine binding sites (kappa 2-receptors) from 98.2 +/- 9 to 74.9 +/- 8 fmol (mg protein)-1 in the hippocampus when compared with SHR controls. A small decrease in kappa 2-receptor density in the pons of WKY rats was also observed after U-50488H treatment (control, 51.2 +/- 5; U-50488H-treated, 24.3 +/- 9 fmol (mg protein)-1. Although SHR blood pressure values were consistently reduced by treatment with kappa-agonists, there was little if any significant change in apparent numbers of kappa 1- or kappa 2-receptors or their affinities in any of the brain regions examined. These data indicate that although chronic treatment with kappa-agonists reduces blood pressure in SHR, the treatment does not elicit major changes in brain kappa-receptors either in SHR or in WKY rats. The potential use of kappa-agonists for treating hypertension might not cause receptor changes in the brain and might, therefore, result in fewer side effects or negligible rebound hypertension.  相似文献   
97.
Orbital implant infection is a rare cause of anophthalmic socket pain. Because of the potential danger of infection spreading to nearby structures, it is of paramount importance to diagnose the condition as soon as possible. Scintigraphy is a method for diagnosis of graft infections by radioisotopic imaging of inflammatory sites. We report on a patient with socket pain 3 months after implantation of an acrylic implant. The socket appearance was normal and there were no signs of infection other than culture-positive socket exudation. Three consecutive computed tomography scans revealed no abnormalities. 99mTc leukocyte scintigraphy revealed white blood cell accumulation at the implantation site. The implant was removed and cultured. This produced Staphylococcus epidermidis and R. equii. A parenteral antibiotic treatment was instituted with subsequent improvement of symptoms. Four months later, after negative scintigraphy, a hydroxyapatite implant was inserted, demonstrating full vascularization on a bone scan after 2 months. Two months later, the patient developed the previous symptoms, with all of the former findings, including positive scintigraphy. The implant was removed, revealing a microabscess on the anterior aspect, producing S. epidermidis on culture. We conclude that scintigraphy using 99mTc-labeled leukocytes is a useful technique in diagnosing low-grade orbital infection.  相似文献   
98.
This study investigated and compared ideas about parenting in Argentine, Belgian, French, Israeli, Italian, Japanese, and U.S. mothers of 20-month-olds. Mothers evaluated their competence, satisfaction, investment, and role balance in parenting and rated attributions of successes and failures in 7 parenting tasks to their own ability, effort, or mood, to difficulty of the task, or to child behavior. Few cross-cultural similarities emerged; rather, systematic culture effects for both self-evaluations and attributions were common, such as varying degrees of competence and satisfaction in parenting, and these effects are interpreted in terms of specific cultural proclivities and emphases. Child gender was not an influential factor. Parents' self-evaluations and attributions help to explain how and why parents parent and provide further insight into the broader cultural contexts of children's development.  相似文献   
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