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61.
Increasingly, health care professionals and the public are asking questions about the role of the hospital in meeting community need including its not-for-profit tax status. This article reviews the community benefit literature, provides a framework for understanding how a hospital community benefit program was developed, and delineates through a structured case study the lessons learned from this experience. It provides the practitioner with a context in which other hospitals may replicate the program and gives researchers a substantive case study that may be used as the basis for the empirical testing of community benefit models. The authors also outline the many difficult issues faced by a typical community hospital as it attempted to examine and develop additional responses to community need.  相似文献   
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Tumor necrosis factor alpha (TNF-alpha) may play a central role in the disease pathogenesis which occurs as a consequence of chlamydial infection. To investigate the importance of TNF-alpha gene promoter polymorphisms and TNF-alpha levels in tear fluid in scarring trachoma, a large matched-pair case-control study was performed in The Gambia. The -308A allele was present in a higher proportion of patients (28.4%) than controls (18.4%), with an increasing association for homozygotes (chi2 for trend, P = 0.032; allele frequency, 0.163 in patients and 0.099 in controls; chi2, P = 0.025). For the -238A allele, the association was similar but not significant. The disease association was highly significant when the number of either -308A or -238A sites in an individual was considered (P = 0.003). TNF-alpha promoter alleles are tightly linked to some HLA class I and II alleles, but multivariate analysis confirmed that the disease associations were independent of HLA, although a class I allele, A*6802, is also associated with disease. TNF-alpha was more frequently detected in tear samples from patients (27.6%) than from controls (15.9%), increasingly so for higher levels of detectable TNF-alpha (P = 0.015). Among patients, detectable TNF-alpha in tears was highly associated with the presence of ocular chlamydial infection (P < 0.001). The results indicate that TNF-alpha plays a major role in the tissue damage and scarring which occurs as a consequence of Chlamydia trachomatis infection.  相似文献   
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Modulation of N-methyl-D-aspartate receptors in the brain by protein phosphorylation may play a central role in the regulation of synaptic plasticity. To examine the phosphorylation of the NR1 subunit of N-methyl-D-aspartate receptors in situ, we have generated several polyclonal antibodies that recognize the NR1 subunit only when specific serine residues are phosphorylated. Using these antibodies, we demonstrate that protein kinase C (PKC) phosphorylates serine residues 890 and 896 and cAMP-dependent protein kinase (PKA) phosphorylates serine residue 897 of the NR1 subunit. Activation of PKC and PKA together lead to the simultaneous phosphorylation of neighboring serine residues 896 and 897. Phosphorylation of serine 890 by PKC results in the dispersion of surface-associated clusters of the NR1 subunit expressed in fibroblasts, while phosphorylation of serine 896 and 897 has no effect on the subcellular distribution of NR1. The PKC-induced redistribution of the NR1 subunit in cells occurs within minutes of serine 890 phosphorylation and reverses upon dephosphorylation. These results demonstrate that PKA and PKC phosphorylate distinct residues within a small region of the NR1 subunit and differentially affect the subcellular distribution of the NR1 subunit.  相似文献   
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In contrast to the many neural studies into the mechanisms of sleep onset and maintenance, few studies have focused specifically on awakening from sleep. However, the abrupt electrographic changes and large brief cardio-respiratory activation at awakening suggest that a distinct, transiently aroused, awake state may exist compared to later wakefulness. To test this hypothesis we utilized the acoustic startle reflex, a standard un-conditioned reflex elicited by a sudden loud noise. This reflex is modulated under specific conditions, one being a diminution of startle when a quieter pre-stimulus is presented immediately before the loud stimulus. This pre-pulse inhibition (PPI) is used as a measure of sensorimotor gating, with smaller PPI indicating less filtering of sensory inputs and increased responsiveness to external stimuli. Eight rats with electrodes for recording sleep-wake state were studied. An accelerometer measured startle responses. The startle reflex was elicited by 115 dB, 40 ms tones. PPI was produced by 74 dB, 20 ms tones preceding the 115 dB tone by 100 ms. Responses within 100 ms were measured. Stimuli were applied either 3-10 s after spontaneous awakenings, or in established wakefulness (> 30 s). Responses to the startle stimuli alone were similar in the different awake states (P = 0.821). However, PPI was smaller at awakening from non-REM sleep compared to established wakefulness (45.4 +/- 7.5% vs. 74.3 +/- 6.1%, P = 0.0002). PPI after awakening from REM sleep (52.8 +/- 17.9%) was not significantly different than established wakefulness (P = 0.297). Reduced PPI of the startle reflex at awakening from non-REM sleep supports the hypothesis that wakefulness immediately after spontaneous sleep episodes is neurophysiologically distinct from later wakefulness and associated with reduced gating of motor responses to sensory inputs. Spontaneous activation of this distinct, transiently aroused, state upon awakening may serve a protective function, preparing an animal to respond immediately to potentially threatening stimuli.  相似文献   
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While the slow onset of desensitization of nicotinic acetylcholine receptors (AChRs), relative to the rate of acetylcholine removal, excludes this kinetic state from shaping synaptic responses in normal neuromuscular transmission, its role in neuromuscular disorders has not been examined. The slow-channel congenital myasthenic syndrome (SCCMS) is a disorder caused by point mutations in the AChR subunit-encoding genes leading to kinetically abnormal (slow) channels, reduced miniature endplate current amplitudes (MEPCs), and degeneration of the postsynaptic membrane. Because of this complicated picture of kinetic and structural change in the neuromuscular junction, it is difficult to assess the importance of the multiple factors that may be responsible for the reduced endplate current amplitudes, and ultimately the clinical syndrome. In order to address this we have used a transgenic mouse model for the SCCMS that has slow AChR ion channels and reduced endplate responsiveness in the absence of any of the degenerative changes. We found that the reduction in MEPC amplitudes in these mice could not be explained by either reduced AChR number or by reduced AChR channel conductance. Rather, we found that the mutant AChRs in situ manifested an activity-dependent reduction in sensitivity that caused diminished MEPC and endplate current amplitude with nerve stimulation. This observation demonstrates that the basis for the reduction in MEPC amplitudes in the SCCMS may be multifactorial. Moreover, these findings demonstrate that, under conditions that alter their rate of desensitization, the kinetic properties of nicotinic AChRs can control the strength of synaptic responses.  相似文献   
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The expression of the NMDA subtype of glutamate receptors was investigated by Western blot analysis and RT-PCR in cultured chick Bergmann and Müller glial cells. Using subunit-specific antibodies directed to the carboxy terminus of the rat NMDAR2A/B we detected the expression of the NMDAR2 subunit in both kinds of culture. The functional subunit of the NMDA receptor, NMDAR1, was detected by means of RT-PCR. These results, together with our previous functional characterization of NMDA receptors in radial glia, provide conclusive evidence for the expression of functional NMDA receptor/channels in Bergmann and Muller glia cells. Our findings strengthen the notion of a modulatory role of glial cells in synaptic transmission.  相似文献   
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OBJECTIVE: To study the effect of renal impairment on the pharmacokinetics of sertindole. METHODS: A single 4 mg oral dose of sertindole was given to normal subjects (n = 6) and subjects with various degrees of impaired renal function (n = 18) classified into mild, moderate, and severe/hemodialysis based on their creatinine clearance). The relationships between the pharmacokinetic parameters and the degree of renal impairment were investigated using regression analysis with creatinine clearance as an explanatory variable along with body weight. Subjects were also genotyped for CYP2D6-A or 2D6-B mutations. RESULTS: The mean CL/f and t1/2 values of sertindole ranged from 14 to 31 1.h-1 and from 73 to 93 h, respectively, and were not significantly related to creatinine clearances. There was no indication of any influence of creatinine clearance on the fraction of sertindole (0.994-0.995) binding to plasma proteins. The total fraction of the sertindole dose removed by dialysis was less than 0.1% Subjects with B/B genotype (n = 2) for CYP2D6 were associated with a distinctly lower clearance of sertindole (6.3 vs 25.3 1.h-1) than subjects with wt/wt genotype for CYP2D6. CONCLUSIONS: Since the pharmacokinetics of sertindole are unchanged by renal impairment, dosage adjustment does not appear to be necessary for subjects with various degrees of renal insufficiency or subjects with renal failure requiring hemodialysis.  相似文献   
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