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OBJECTIVES: To report the features of malignancies responsible for a chest wall mass and involving the sternum, the sternocostal and/or sternoclavicular joints, the chondrocostal junction and/or the adjacent soft tissues. METHODS: The medical records of patients with a chest wall mass due to malignant disease were reviewed retrospectively. The following data were abstracted from each record: characteristics of the pain and mass, constitutional symptoms, physical findings, laboratory test results, findings from imaging studies (plain radiographs, computed tomography and magnetic resonance imaging of the chest, radionuclide bone scan), histologic features of the biopsy specimen from the chest wall mass and origin of the mass. RESULTS: Seven men and three women with a mean age of 53.1 years were included in the study. A single patient had a history of malignant disease (lymphoma); in the remaining nine patients the chest wall mass was the first manifestation of the malignancy. All ten patients had pain with a mixed time pattern. The mass was located on the sternum in half the patients and in a parasternal location in the other half. Erythrocyte sedimentation rate elevation was found in seven patients, an increased serum level of lactate dehydrogenase in one and a monoclonal immunoglobulin in three. Sternal lesions were visible on plain radiographs in four patients. Computed tomography of the chest consistently disclosed sternal or sternocostal lytic lesions with spread to the adjacent soft tissues; in five cases, enlarged lymph nodes were visible in the anterior part of the mediastinum. Magnetic resonance imaging of the chest did not add to the information provided by computed tomography. Radionuclide uptake on the bone scan was increased, decreased, or normal at the site of the lesion. The cause was Hodgkin's disease in two cases, non-Hodgkin's lymphoma in three, metastatic bone disease in two (from an adenocarcinoma of the lung and a hepatocarcinoma, respectively), multiple myeloma in one, and solitary plasmacytoma in two. CONCLUSION: A chest wall mass can be caused by a known or as yet undiagnosed malignancy. Chest wall involvement due to malignant disease in rare, however. The specific features of sternal metastases, lymphomas involving the sternum, and sternal plasmacytomas are discussed. Nonmalignant chest wall lesions that can manifest as a bulging or swelling of the chest wall are reviewed. 相似文献
455.
This presentation reviews the functional properties of different permeable junctions (microplasmodesmata of filamentous cyanobacteria, septal pores of fungi, and gap junctions of animals). Examples of the distribution of power by ionic fluxes and electric current through permeable cell-cell junctions are considered. Based on the analysis of intercellular communication occurring during apical growth of hyphae of wild-type and mutant lines of the mycelial fungus Neurospora crassa, approaches to studies of the molecular and genetic mechanisms of self-organization in systems of cells with permeable junctions are discussed. 相似文献
456.
ES Dremina II Vlasova TV Vakhrusheva VS Sharov OA Azizova 《Canadian Metallurgical Quarterly》1997,42(5):1079-1087
The effect of metal cations on copper-catalyzed lipid peroxidation (LPO) of low density lipoproteins (LDL) was examined. The presence of metal cations in the incubation media containing LDL (0.8 mg protein/ml) and CuSO4 (0-80 microM) influenced on LPO of LDL as evident by the measurement of TBARS. With the concentrations of CuSO4 less than 10 microM, the metal cations caused an increase in LDL peroxidation. Zn2+ appeared to be the most effective inductor, Mn2+ was less effective, and the influence of Ca2+ and Mg2+ was insignificant. With greater CuSO4 concentrations Mg2+ showed no effect on TBARS formation in LDL while the addition of other nontransition metal cations to the incubation mixture led to the inhibition of LDL peroxidation. The capacity for inhibition decreased in the row Mn2+ > Zn2+ > Ca2+ > Mg2+. The possible mechanism explaining these results may be in the competition of metal ions for copper binding sites on LDL. Our results allow to suggest the existence of two types of copper binding sites on LDL, tight-binding sites which are non-effective in LPO and effective weak-binding sites. 相似文献
457.
Saccharomyces cerevisiae mitochondria possess polyphosphatases that are tightly bound to the membranes and differ from soluble polyphosphatase of these organelles in a number of properties. Molecular weights of the membrane-bound polyphosphatases are 120 and 76 kD, and the molecular weight of the soluble polyphosphatase is about 36 kD. All three enzymes are evidently monomers, since antibodies against purified cell-envelope polyphosphatase of S. cerevisiae reacted with 115, 78, and 37 kD polypeptides in immunoblotting. The activities of membrane-bound and soluble polyphosphatase are maximal at neutral pH. The soluble polyphosphatase activity is stimulated by divalent cations, unlike the membrane-bound enzymes which are inhibited by the same cations including Mg2+. Monovalent cations do not affect the activity of the soluble enzyme but stimulate polyphosphatases in the membrane preparation. The specific activities for hydrolysis of polyphosphates with average chain lengths of 9 to 188 phosphate residues are enhanced by increasing the degree of substrate polymerization in the case of the membrane preparation and are unchanged in case of the soluble enzyme. Affinity of the soluble enzyme to polyphosphates is 5-10 times higher than that of the membrane-bound polyphosphatases. In the soluble fraction of mitochondria, high tripolyphosphatase activity is detected which is approximately 80% of that in isolated mitochondria. 相似文献
458.
The present study was undertaken in order to evaluate whether arteriography changed the planned treatment (carotid endarterectomy) of patients with symptomatic carotid artery disease, who had been investigated primarily by ultrasound Duplex scanning. The material was comprised of 50 consecutive patients admitted for arteriography. All patients were symptomatic and were by ultrasound examination found to have lesions of the relevant internal carotid artery (ICA). In three cases arteriography was performed because ultrasound examination was inconclusive. Of the remaining 47 cases, arteriography only changed the planned treatment in three. In one case, arteriography showed a long stenosis continuing into the intracranial part of the ICA, which was not observed by ultrasound. In two cases of minor disease ultrasound overestimated the degree of stenosis. The study concludes that carotid endarterectomy may be performed based on ultrasound duplex scanning, without prior arteriography, if the degree of stenosis is 70% or greater and if the distal end of the stenosis is clearly extracranial. 相似文献
459.
The management of the abnormal smear in pregnancy remains a challenge to the modern colposcopist. Colposcopy in pregnancy is difficult. Anatomic variants can mimic disease. Significant cytologic overall detection of low-grade squamous intraepithelial lesions demands an increased understanding of physiologic variants in pregnancy. Possible recent increases in cervical cancer incidence in younger women requires comprehensive knowledge of warning signs of early invasion. Modern management approaches must temper the need for accurate exclusion of cancer with the risk of overly aggressive interference in patients without disease or with very minor atypia. 相似文献
460.
KB Aslanidi OV Aslanidi DM Vachadze TV Potapova LM Cha?lakhian 《Canadian Metallurgical Quarterly》1997,352(6):826-830
A major group of systemic autoimmune diseases is associated with abnormal lymphoproliferation, as a result of defects in the termination of lymphocyte activation and growth. Recent progress has been made in understanding the causes and consequences of these abnormalities. At the molecular level, the defects in CD95 and its ligand are only the most obvious reasons for the breakdown of 'clonal contraction' which in fact requires the participation of multiple gene products, including the IL-2-IL-2-receptor system, to set up a functional apoptotic machinery. 相似文献