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51.
HD Di Paolo MC Aggio V Fernández MC Tafetani J Blasco I Slavutsky G Andreoli M Gronda C Bianchi de Di Risio 《Canadian Metallurgical Quarterly》1997,57(3):323-326
Evidence is rapidly emerging which suggests that uncoupling protein 2 (UCP2), by virtue of its ubiquitous expression, may be important for determining basal metabolic rate. To assess the functional modulation of UCP2 gene expression in relation to body weight control, we examined the effects of hyperthyroid state induced by chronic treatment with triiodothyronine (T3) on UCP2 mRNA expression in male rats. Daily subcutaneous injection of T3 (37 pmol/100 g body weight) for 7 days increased UCP2 mRNA expression in brown adipose tissue (BAT), white adipose tissue (WAT) and the soleus muscle 1.6-, 1.6- and 1.7-fold compared to the controls, respectively, and increased UCP1 mRNA expression in BAT 1.2-fold. In contrast, the same treatment with T3 decreased both ob mRNA expression in WAT and plasma leptin level 0.5-fold for each. The present results suggest that T3 may directly increase UCP2 expression independently of leptin action. 相似文献
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Ohne Zusammenfassung 相似文献
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Larynx-associated lymphoid tissue (LALT) in young children 总被引:1,自引:0,他引:1
A Kracke AS Hiller T Tschernig M Kasper WJ Kleemann HD Tr?ger R Pabst 《Canadian Metallurgical Quarterly》1997,248(3):413-420
BACKGROUND: Mucosa-associated lymphoid tissue (MALT) plays a central role in mucosal immunity. Whereas the characteristics and function of MALT in the intestine are well established, almost nothing is known about MALT in the larynx. METHODS: In this study we examined the morphology and the lymphocyte subset composition of MALT in the larynges of children who had died of sudden infant death or various defined traumatic or nontraumatic causes. RESULTS: Organized lymphoid tissue was found in the supraglottic parts of the larynx in nearly 80% of the children in both groups. This lymphoid tissue showed all morphological signs of MALT, such as typical lymphoid follicles with germinal centers, infiltration of the overlying epithelium by lymphocytes, and high endothelial venules (HEV). Thus we will use the term LALT (larynx-associated lymphoid tissue) to refer to this tissue. The lymphoid follicles of LALT contained mainly B lymphocytes with some CD4+ lymphocytes in the germinal centers. Remarkably, T lymphocytes of both subset types and B lymphocytes were observed in comparable numbers in the parafollicular area. CONCLUSIONS: We assume that LALT is a physiological structure of the larynx in young children. The morphology and the distribution of lymphocyte subsets are similar to those of MALT in the human gut. LALT may be a regular part of the mucosal immune system in young children with the role of respiratory inductive site for mucosal immunity. 相似文献
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Cholinergic neurons of the mesopontine nuclei are strongly implicated in behavioral state regulation. One population of neurons in the cholinergic zone of the laterodorsal tegmentum and the pedunculopontine nuclei, referred to as rapid eye movement (REM)-on neurons, shows preferential discharge activity during REM sleep, and extensive data indicate a key role in production of this state. Another neuronal group present in the same cholinergic zone of the laterodorsal tegmentum and the pedunculopontine nuclei, referred to as Wake/REM-on neurons, shows preferential discharge activity during both wakefulness and REM sleep and is implicated in the production of electroencephalographic activation in both of these states. To test the hypothesis of differential serotonergic inhibition as an explanation of the different state-related discharge activity, we developed a novel methodology that enabled, in freely behaving animals, simultaneous unit recording and local perfusion of neuropharmacological agents using a microdialysis probe adjacent to the recording electrodes. Discharge activity of REM-on neurons was almost completely suppressed by local microdialysis perfusion of the selective 5-HT1A agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT), although this agonist had minimal or no effect on the Wake/REM-on neurons. We conclude that selective serotonergic inhibition is a basis of differential state regulation in the mesopontine cholinergic nuclei, and that the novel methodology combining neurophysiological and neuropharmacological information from the freely behaving animal shows great promise for further insight into the neural basis of behavioral control. 相似文献
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WR Schwan SN Coulter EY Ng MH Langhorne HD Ritchie LL Brody S Westbrock-Wadman AS Bayer KR Folger CK Stover 《Canadian Metallurgical Quarterly》1998,66(2):567-572
Staphylococcus aureus is an important pathogen of humans and other animals, causing bacteremia, abscesses, endocarditis, and other infectious syndromes. A signature-tagged mutagenesis (STM) system was adapted for use in studying the genes required for in vivo survival of S. aureus. An STM library was ultimately created in S. aureus RN6390, with Tn917 being used to create the transposon mutations. Pools of S. aureus RN6390 mutants were screened in mouse abscess, bacteremia, and wound infection models for growth attenuation after in vivo passage. One of the mutants that was identified displayed marked attenuation following large-pool screening in all three animal models, which was confirmed in bacteremia and endocarditis models of infection with a smaller pool of mutants. Sequence analysis of the entire open reading frame showed a 99% identity to the high-affinity proline permease (putP) gene characterized in another strain of S. aureus. In wound and murine abscess infection models, the putP mutant was approximately 10-fold more attenuated than was wild-type strain RN6390. Another S. aureus strain transduced with the putP mutation also displayed an attenuated phenotype after passage in the wound model. A [3H]proline uptake assay showed that less proline was specifically transported into the putP mutant than into strain RN6390. The reduced viability of the bacteria possessing the mutation in the S. aureus high-affinity proline permease suggests that proline scavenging by the bacteria is important for in vivo growth and proliferation and that analogs of proline may serve as potential antistaphylococcal therapeutic agents. 相似文献
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In recent years there has been spectacular progress in the approach to various disorders of the spinal column. Owing to improved methods of osteosynthesis there is no longer so much need for long periods of postoperative bed rest. Of all the scolioses, idiopathic scoliosis is most common. The vast majority of these cases are not clinically significant. What is seen in the remaining cases if left untreated is a progression in the curvature during growth. Progressive idiopathic scoliosis can be effectively treated using conservative methods. Screening at school is an important part of this process. If the curvature proves progressive and skeletal growth is not complete a brace can be prescribed. Use of this strategy and form of treatment can avoid progression of the curvature and development of serious deformities. This conservative therapy has markedly reduced the need for corrective surgery. Scheuermann's disease is characterized by a fixed dorsal thoracic kyphosis. Progressive Scheuermann's kyphosis can be effectively treated using a brace. The majority of fractures of the vertebral bodies can be treated conservatively. However, serious fractures normally require surgical intervention. In the industrialised Western world, low back pain is a major health problem and the foremost cause of disability and unfitness for work. Low back pain caused by degenerative disease of the spinal column should be treated using a multidisciplinary approach. The development of advanced operative techniques and osteosynthesis methods has made it possible to treat metastases of the spine surgically. The effects of this treatment on the quality of life are encouraging. 相似文献