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751.
Motivation plays an important part in an elderly individual's ability to recover from a disabling event. On the other hand, apathy is a lack of motivation. The Apathy Evaluation Scale (AES) is an 18-item instrument that rates a person's thoughts, actions, and emotions over the previous 4 weeks. The purpose of this study was to use the AES with 102 patients in a geriatric rehabilitation program to determine if it predicted improved function after rehabilitation. In addition, a short 7-item version of the AES was tested. A strong correlation was demonstrated between the 18-item AES and the 7-item AES, the Mini-Mental State Examination, and the Geriatric Depression Scale. In separate regression analyses, we found that admission function and both the 18-item and 7-item AES were significant predictors of discharge function, and that functional level at admission to rehabilitation accounted for 31% of the variance in function after rehabilitation. The findings suggest that the AES might be an appropriate measure of motivation in older adults and might predict success in rehabilitation. Moreover, the ability to identify patients with low motivation can alert healthcare providers to develop interventions to improve older adults' motivation and help them attain and maintain their highest functional level.  相似文献   
752.
A follow-up study was conducted on 60 patients who had standard en bloc anterior temporal lobe resection, including mesiotemporal structures, as treatment for temporal lobe lesions associated with chronic, medically intractable seizures. Lesions were identified as glial tumors, hamartomas, or vascular malformations. Long-term outcome was assessed in terms of seizure frequency and certain psychosocial sequelae. Seizure onset occurred at an average age of 15 years (median = 13.5 years), and patients experienced seizures for an average of 13 years prior to surgery. The mean time of follow-up was 8.4 years postsurgery (median = 6 years). The Kaplan-Meier curve at median follow-up showed a seizure-free rate of 80%. Late seizure recurrence was documented for three patients; two had been seizure-free for 10 years and one for 15 years after surgery, before re-onset of seizures in the absence of tumor recurrence. A prolonged history of seizures prior to surgery was associated with a poorer seizure outcome (p = 0.06), suggesting that secondary epileptogenesis at sites distant to the lesion may develop with years of uncontrolled seizures. There was a low tumor recurrence rate of 3.3% (two cases). The psychosocial outcome was generally good, with 67% working or engaged in educational studies, and improvement noted in 59% of cases for one or more of the psychosocial factors investigated. This study confirms that anterior temporal lobe resection for temporal lesions associated with chronic seizures is a successful treatment with a high seizure-free rate following surgery and good psychosocial outcome.  相似文献   
753.
Ephrin-A5 (AL-1/RAGS), a ligand for Eph receptor tyrosine kinases, repels retinal axons in vitro and has a graded expression in the superior colliculus (SC), the major midbrain target of retinal ganglion cells. These properties implicate ephrin-A5 in the formation of topographic maps, a fundamental organizational feature of the nervous system. To test this hypothesis, we generated mice lacking ephrin-A5. The majority of ephrin-A5-/- mice develop to adulthood, are morphologically intact, and have normal anterior-posterior patterning of the midbrain. However, within the SC, retinal axons establish and maintain dense arborizations at topographically incorrect sites that correlate with locations of low expression of the related ligand ephrin-A2. In addition, retinal axons transiently overshoot the SC and extend aberrantly into the inferior colliculus (IC). This defect is consistent with the high level of ephrin-A5 expression in the IC and the finding that retinal axon growth on membranes from wild-type IC is inhibited relative to that on membranes from ephrin-A5-/- IC. These findings show that ephrin-A5 is required for the proper guidance and mapping of retinal axons in the mammalian midbrain.  相似文献   
754.
PURPOSE: We determined the clinical utility of proton MR spectroscopy in defining the extent of disability in benign versus secondary-progressive multiple sclerosis (MS). METHODS: Thirty patients with clinically definite MS, including 16 patients with benign MS and 14 with secondary-progressive MS, and a group of 13 healthy volunteers were studied with combined stimulated-echo acquisition mode proton MR spectroscopy and MR imaging (all patients received contrast material). RESULTS: Acute enhancing lesions of benign and secondary-progressive MS were characterized by a reduction in N-acetylaspartate (NAA)/choline and NAA/creatine and an increase in inositol compounds/creatine as compared with normal white matter. Such variations were also detected in chronic unenhancing lesions in patients with secondary-progressive MS, although they were not found in chronic unenhancing lesions in patients with benign MS. Chronic lesions of the two forms of the disease have significative differences in NAA and inositol signals. CONCLUSION: Proton MR spectroscopy is able to show metabolic changes occurring in the white matter of patients with MS. Such changes differ according to the phase (acute versus chronic) and the clinical form (benign versus secondary-progressive) of the disease.  相似文献   
755.
Glycogen storage disease type II (GSDII), an autosomal recessive myopathic disorder, results from deficiency of lysosomal acid alpha-glucosidase. We searched for mutations in an evolutionarily conserved region in 54 patients of differing phenotype. Four novel mutations (D645N, G448S, R672W, and R672Q) and a previously described mutation (C647W) were identified in five patients and their deleterious effect on enzyme expression demonstrated in vitro. Two novel frame-shifting insertions/deletions (delta nt766-785/insC and +insG@nt2243) were identified in two patients with exon 14 mutations. The remaining three patients were either homozygous for their mutations (D645N/D645 and C647W/C647W) or carried a previously described leaky splice site mutation (IVS1-13T-->G). For all patients "in vivo" enzyme activity was consistent with clinical phenotype. Agreement of genotype with phenotype and in vitro versus in vivo enzyme was seen in three patients (two infantile patients carrying C647W/C647W and D645N/+insG@nt2243 and an adult patient heteroallelic for G648S/IVS1-13T-->G). Relative discordance was found in a juvenile patient homozygous for the non-expressing R672Q and an adult patient heterozygous for the minimally expressing R672W and delta nt766-785/+insC. Possible explanations include differences in in vitro assays vs in vivo enzyme activity, tissue specific expression with diminished enzyme expression/stability in fibroblasts vs muscle, somatic mosaicism, and modifying genes.  相似文献   
756.
Ecological theory asserts that the Ames' distorted room illusion (DRI) occurs as a result of the artificial restriction of information pickup. According to J. J. Gibson (1966, 1979), the illusion is eliminated when binocular vision and/or head movement are allowed. Exp I, with 144 undergraduates, used size-matching technique employing discs placed within an Ames' distorted room to measure the DRI. Ss viewed the distorted room or a control apparatus under 4 viewing conditions (i.e., restricted or unrestricted head movement), using monocular and binocular vision. In Exp II, 20 Ss viewed binocularly and were instructed to move freely while making judgments. Findings show that the DRI decreased with increases in viewing access, although it persisted under all viewing conditions. The persistence of the illusion is seen as contradicting Gibson's position. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
757.
This study examines the effect of heating the fibers of a unidirectional mat on the resin flow between fibers. The model used assumes steady incompressible flow in the direction of the fibers. The resulting Stoke' equation is solved analytically assuming linear variation of pressure, while the energy equation is solved numerically using finite differencing. An iterative scheme is used to update velocity in the direction of flow by using the temperature dependence of viscosity according to the Arrhenius equation. The fibers are heated conductively from their ends producing a temperature distribution down the length of the fibers. Velocity profiles between fibers, resulting from thermally-induced viscosity gradients, are compared for various steps along the fiber lengths. The resulting reductions in flow time are compared to those for fibers held at a constant temperature and to the flow times for the simple isothermal case of unheated  相似文献   
758.
759.
Central and peripheral administration of DDAVP increase locomotor activity in rats in doses that alter brain dopamine neurochemistry. In order to delineate the role of catecholamines in this behavioural effect of DDAVP, the effects of different catecholamine manipulating agents on DDAVP-induced locomotor stimulation were studied in rats. The catecholamine depleting agent reserpine (5 mg/kg), administered alone or together with the catecholamine synthesis inhibitor alpha-methyltyrosine (250 mg/kg), completely prevented the locomotor stimulatory effect of DDAVP. The dopamine D1 receptor antagonist Sch-23390 (0.01 and 0.03 mg/kg) significantly antagonized the DDAVP-induced locomotor stimulation when administered in the higher dose, that also produced a significant reduction of locomotor activity per se, whereas the dopamine D2 receptor antagonist raclopride (0.08 and 0.16 mg/kg) had no significant effect. The two dopamine blockers administered together produced a significant, dose-dependent reduction of DDAVP-induced locomotor stimulation, while controls were not significantly affected. Also the alpha-adrenoceptor antagonist phenoxybenzamine decreased the DDAVP-induced locomotor stimulation in a dose (20 mg/kg) that did not influence locomotor activity in controls, and, finally, administration of Sch-23390, raclopride and phenoxybenzamine antagonised the DDAVP-induced effect in a dose combination that failed to influence locomotor activity per se. In vivo microdialysis experiments in awake, freely moving rats indicated that DDAVP increases dopamine overflow in the nucleus accumbens, a brain area of importance for initiation of locomotor activity, by approximately 25%, as compared to baseline levels. Taken together, these results indicate that the central stimulatory action of DDAVP involves granula-mediated dopamine release and subsequent activation of dopamine D1 and D2 receptors, and that alpha-adrenoceptors possibly also are involved.  相似文献   
760.
The solution structure of the oligomerization domain of cartilage matrix protein (also known as matrilin-1) has been determined by heteronuclear NMR spectroscopy. The domain folds into a parallel, disulfide-linked, three-stranded, alpha-helical coiled coil, spanning five heptad repeats in the amino acid sequence. The sequence of the first two heptad repeats shows some deviations from the consensus of hydrophobic and hydrophilic residue preferences. While the corresponding region of the coiled coil has a higher intrinsic flexibility, backbone alpha-helix and superhelix parameters are consistent with a regular coiled coil structure.  相似文献   
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