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161.
162.
The orbital manifestations of Graves' disease frequently constitute the major and distressing portion of the morbidity in this poorly understood process. Patients with optic neuropathy, exposure keratopathy or disfiguring proptosis may be aided considerably by decompression to permit swollen orbital contents to move into the maxillary and ethmoid sinus cavities. Experience with 38 patients treated over a five-year period indicates that antral-ethmoidal decompression is a logical, successful form of therapy and generally free of serious complications. it may provide benefit earlier in the course of Graves' exophthalmopathy than has been accepted in the past. 相似文献
163.
164.
NS Cheung CJ Pascoe SF Giardina CA John PM Beart 《Canadian Metallurgical Quarterly》1998,37(10-11):1419-1429
Excitotoxicity induced by L-glutamate (Glu), when examined in a pure neuronal cortical culture, involved widespread apoptosis at concentrations of 1-10 microM as part of a continuum of injury, which at its most servere was purely necrotic. Cells, maintained in chemically defined neurobasal/B27 medium, were exposed at d7 for 2 h to Glu (1-500 microM), and cellular injury was analysed 2 and 24 h after insult using morphology (phase-contrast microscopy), a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) viability assay, nuclear staining with 4,6-diamidino-2-phenylindole (DAPI), terminal transferase-mediated dUTP nick end-labelling (TUNEL) and DNA fragmentation by gel electrophoresis. Glu-mediated neurotoxicity was prevented by MK-801 (5 microM), whilst CNQX (20 microM) attenuated injury by 20%. Exposure to intensive insults (100 and 500 microM Glu) induced necrosis characterized by rapid cell swelling (< 2 h) and lack of chromatin condensation, confirmed by DAPI nuclear staining. In contrast, mild insults (< 20 microM Glu) failed to produce acute neuronal swelling at < 2 h, but 24 h after injury resulted in a large number of apoptotic nuclei as confirmed by TUNEL and electrophoretic evidence of DNA fragmentation, which was attenuated by cycloheximide (0.1 microg/ml). Our findings indicate for the first time that physiological concentrations of Glu produce neuronal injury across a continuum involving apoptosis (< 20 microM) and increasingly necrosis(> 20 microM), dependent on the severity of the initial insult. 相似文献
165.
166.
MHC molecules present peptides in their binding groove to T-cell receptors inducing proliferation or cytotoxicity of alloreactive T cells. A previously generated human monoclonal antibody (mAb) UL-5 A1, recognizing a conformational epitope formed by HLA DR1/DRB1*0101 molecules and HLA-A2 derived peptides, demonstrates T-cell-like recognition of the peptide/MHC complex (PMC). To study the genes of the antigen binding region, the nucleotide sequences of the rearranged genes in the variable regions of UL-5 A1 were determined and the V-gene usage (VH3, V lambda 2) was identified by comparison with published germlines. The genes encoding heavy (Fd) and light (L) chains of UL-5 A1 were linked and expressed in a bacterial system. Specificity of the recombinant Fab-5 A1 was determined with HLA-typed LCLs by flow cytometric analysis. As demonstrated in competitive inhibition assays, UL-5 A1 and Fab-5 A1 recognize the same PMC epitope on HLA-A2+, -DR1/DRB1*0101+ typed LCLs. Additionally, mAb UL-5 A1 and Fab-5 A1 both recognize HLA-A2-, -DR1/DRB1*0101+ LCLs exogenously loaded with HLA-A2 peptides (105-117, 103-117). UL-5 A1-like antibodies against peptide/MHC complexes could prove valuable tools for research on T-cell recognition and MHC function. 相似文献
167.
MJ Eppinger ML Jones GM Deeb SF Bolling PA Ward 《Canadian Metallurgical Quarterly》1995,58(6):713-718
Using a rat lung model, we sought to characterize the time course for ischemia-reperfusion injury and the role of neutrophils in the development of injury. Adult male Long-Evans rats underwent left thoracotomy with dissection and clamping of the left pulmonary artery, bronchus, and vein for 90 min, resulting in complete left lung ischemia. The lungs were then ventilated and reperfused for up to 4 hr. Time-matched sham animals underwent the identical thoracotomy and hilar dissection, but the lungs were not rendered ischemic. Using vascular permeability of 125I-labeled bovine serum albumin as a measure of reperfusion injury, a bimodal pattern of injury was observed. Compared to sham controls, animals undergoing ischemia-reperfusion demonstrated a significant early phase of lung injury at 30 min of reperfusion (P < 0.0001), followed by partial recovery. A second peak of lung injury was noted after 4 hr of reperfusion (P < 0.001). Myeloperoxidase activity in reperfused lung tissue, a measure of neutrophil sequestration, increased during the reperfusion time course. To determine the role of neutrophils in the development of lung reperfusion injury, additional animals undergoing the identical ischemia-reperfusion protocol received either rabbit anti-rat neutrophil serum or preimmune serum the day prior to operation. Profound neutropenia (< 75/mm3 blood) was confirmed by differential leukocyte counts. Neutropenia had no protective effect against microvascular permeability at 30 min of reperfusion, but there was a significant reduction in lung injury at 4 hr (P < 0.005). We conclude that, during lung ischemia-reperfusion, there is a bimodal pattern of injury, consisting of both neutrophil-independent and neutrophil-mediated events. 相似文献
168.
Before and after oral administration of sustained Ligustrazine, changes of hemorrheology and TXA2/PGI2 were evaluated in 16 patients with advanced chronic pulmonary heart disease. A decrease in whole blood and plasma viscosity, and reductions in hematocrit and fibrinogen were found after one course of treatment with sustained Ligustrazine. The mechanism of these effects may be related to improved modulation of imbalance of TXA2/PGI2 in patients with advanced chronic pulmonary heart disease. 相似文献
169.
H Bouman SF Klis JC de Groot EH Huizing GF Smoorenburg JE Veldman 《Canadian Metallurgical Quarterly》1998,117(1-2):119-130
Click-evoked auditory brainstem responses were recorded in a prosimian primate, the bush baby (Otolemur garnettii), before and after depletion of serotonin (by systemic injection of para-chlorophenylalanine; pCPA) and up to 20 days after discontinuing pCPA injections (during the recovery of serotonin). Biphasic 100 micros clicks were presented at five repetition rates (13.2, 33.2, 53.2, 73.2, and 93.2 clicks/s; RATE) and sound pressure levels (SPL) were varied in 10 dB steps from 120-60 dB SPL peak equivalent. Absolute latencies of vertex-positive peaks I, III, IV, and V were measured from click onset. The latencies from each wave were statistically analyzed with a two-way analysis of variance using either RATE or SPL (but not both) and TIME AFTER pCPA as independent variables. Prior to pCPA, brainstem response latencies increased as a function of both decreasing SPL and increasing RATE. After pCPA, these normal increases in wave latency increased even more, particularly in response to high click rates. After pCPA was discontinued, measurements taken at weekly intervals indicated that latencies decreased after 1 week, increased to the highest values recorded after 2 weeks, and returned to normal after 3 weeks. These dynamic changes were interpreted to be the result of postsynaptic receptor up-regulation during the 10 days of continuous pCPA administration. These results suggest that serotonin plays an important role in sensory processing at the cellular level and, tonically, facilitates the auditory brainstem response to sound. 相似文献
170.