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151.
Fifty patients of various types of cerebral palsy were studied to find out an association between cerebral palsy, EEG abnormalities and development quotient. Seventy-six per cent patients had spastic cerebral palsy. Hypotonic cerebral palsy was the next common type (14%). Athetosis and ataxic forms were found to be rare (2% each). Epilepsy was associated with 56% patients. Clinical types of seizures observed were: Generalised tonic-clonic (43%), myoclonic (17.9%), generalised tonic (10.7%), partial simple (10.7%) and partial complex (17.9%). The incidence of seizures was highest in hypotonic type in which 85.7% had epilepsy. Mean developmental quotient of cerebral palsy patients was 34.9% with maximum retardation in hypotonic cerebral palsy (25.14%). Sixty per cent of patients had abnormal EEG, out of these hypotonic patients had maximum (70%) chances of EEG abnormality followed by spastic patients (55%). Developmental retardation was more severe statistically in the patients with abnormal EEG than normal EEG.  相似文献   
152.
BACKGROUND: Although numerous reports have described interventions designed to influence antibiotic utilization, to our knowledge none have been evaluated in a randomized study. METHODS: Adult inpatients receiving 1 or more of 10 designated parenteral antibiotics for 3 or more days during a 3-month period were randomized to an intervention (n = 141) and a control (n = 111) group using an unblocked, computer-generated random number table. Obstetric patients and those seen in infectious disease consultation were excluded. The intervention group received antibiotic-related suggestions from a team consisting of an infectious disease fellow and a clinical pharmacist. Both groups were evaluated for clinical and microbiological outcomes as well as antibiotic utilization via prospective chart reviews and analysis of the hospital's administrative database. RESULTS: Sixty-two (49%) of the intervention group patients received a total of 74 suggestions. Sixty-three (84%) of these suggestions were implemented; the majority involved changes in antibiotic choice, dosing regimen, or route of administration. Per patient antibiotic charges were nearly $400 less in the intervention group vs controls (P = .05). Almost all the savings were related to lower intravenous antibiotic charges. Clinical and microbiological response, antibiotic-associated toxic effects, in-hospital mortality, and readmission rates were similar for both groups. Multiple linear regression analysis identified randomization to the intervention group and female sex as the sole predictors of lower antibiotic charges. There was a trend toward a shorter length of stay for the intervention group (20 vs 24.7 days, P = .11). CONCLUSIONS: This is the first randomized study to evaluate whether antibiotic choices can be influenced in a cost-effective fashion without sacrificing patient safety. We demonstrate that 50% of patients initially treated with expensive parenteral antibiotics can have their regimens refined after 3 days of therapy and that these modifications result in good clinical outcomes with a substantial reduction in antibiotic expense.  相似文献   
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The yielding, plastic flow, and fracture behavior of UHMWPE plays an important role in wear and failure mechanisms of total joint replacement components. The primary objective of this study was to compare the yielding, plastic flow, and fracture behavior of two implantable grades of UHMWPE (GUR 1120 vs 4150 HP). The first part of this work explored the hypothesis that up to the polymer yield point, the monotonic loading behavior of UHMWPE displays similar true stress strain behavior in tension and compression. Uniaxial tension and compression tests were conducted to compare the equivalent true stress vs strain response of UHMWPE up to 0.12 true strain. During monotonic loading, the equivalent true stress strain behavior was similar in tension and compression up to the yield point. However, investigation of the unloading behavior and permanent plastic deformations showed that classical deviatoric rate independent plasticity theory may dramatically overpredict the permanent strains in UHMWPE. A secondary goal of this study was to determine the ultimate true stress and strain for UHMWPE and to characterize the fracture surfaces after failure. Using a fracture mechanics approach, the critical flaw sizes were used in combination with the true ultimate stresses to predict the fracture toughness of the two resins. A custom video-based strain measurement system was developed and validated to characterize the true stress-strain behavior up to failure and to verify the accuracy of the incompressibility assumption in calculating the true stress-strains up to failure. In a detailed uncertainty analysis, theoretical expressions were derived for the relative uncertainty in digital video-based estimates of nominal strain, true strain, homogeneous stress, and true stress. Although the yielding behavior of the two UHMWPE resins was similar, the hardening and plastic flow behavior clearly discriminated between the GUR 1120 and 4150 HP. A statistically significant difference between the fracture toughness of the two resins was also evident. The long-term goal of this research is to provide detailed true stress strain data for UHMWPE under uniaxial tension and compression for future numerical simulations and comparison with more complex multiaxial loading conditions.  相似文献   
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A recent focus in health care is to develop a seamless transition for patients between the variety of health care agencies with whom they interact. The continuum of care for patients with stroke is complex and many levels of care are required, from acute intervention through to rehabilitation and reintegration into the community. A group of nurses from a variety of agencies in Southwestern Ontario received funding from the Ontario province Wide Nursing Project to effect a desirable change in the way nurses care for the stroke patient. This article describes the Ontario Province Wide Nursing project and the process of and challenges in developing a nursing model for stroke. The development of a nursing model for stroke patients and their families involved conducting nursing, and patient and family focus groups to identify key issues. Thirty-eight nurses participated in the nursing focus groups, and 8 patients and 18 family members participated in the patient and family focus groups. The common themes were the need for improved communication and the need to better prepare patients and families for the many transitions they experience during their recovery from stroke. A Stroke Education Record, which identifies a comprehensive list of potential learning needs of stroke patients and their families, and a Stroke Education and Resource Guide, which provides a reference for nurses, were developed and will be implemented in September 1998. Implementation of the model included a workshop, staff inservices, a self-learning package, and unit displays. Evaluation of the model will include nursing and patient and family focus groups, a chart review, written nursing evaluations, and patient and family telephone interviews.  相似文献   
158.
The objective of this study was to identify, through kinetic analysis of individual elementary reactions, the conditions under which a simple first-order photobleaching kinetic model is sufficient for quantitative fluorescence measurements, and those under which more complex photobleaching kinetics must be considered. Three model systems of various fluorophore densities and distributions were employed to verify the kinetic analysis. The results showed that the photobleaching kinetics of free fluorescein at concentrations lower than 5 microM corresponded closely to a single exponential function and therefore involved predominantly simple unimolecular or pseudounimolecular photochemical reactions. When fluorescein was bound to polyvinyl alcohol (PVA) molecules, the photobleaching kinetics of the densely labeled PVA deviated more from a single-exponential function than sparsely labeled PVA. When fluorescein was bound to a DNA probe, the photobleaching kinetics were more complex and deviated significantly from a single-exponential function, due to one or more bimolecular processes with apparent concentration-dependent photobleaching rate constants. The practical applications of time-integrated fluorescence emission are discussed in the context of simple and complex photobleaching kinetics.  相似文献   
159.
AIMS/BACKGROUND: To characterise clinically a large kindred segregating retinitis pigmentosa and sensorineural hearing impairment in an autosomal dominant pattern and perform genetic linkage studies in this family. Extensive linkage analysis in this family had previously excluded the majority of loci shown to be involved in the aetiologies of RP, some other forms of inherited retinal degeneration, and inherited deafness. METHODS: Members of the family were subjected to detailed ophthalmic and audiological assessment. In addition, some family members underwent skeletal muscle biopsy, electromyography, and electrocardiography. Linkage analysis using anonymous microsatellite markers was performed on DNA samples from all living members of the pedigree. RESULTS: Patients in this kindred have a retinopathy typical of retinitis pigmentosa in addition to a hearing impairment. Those members of the pedigree examined demonstrated a subclinical myopathy, as evidence by abnormal skeletal muscle histology, electromyography, and electrocardiography. LOD scores of Zmax = 3.75 (theta = 0.10), Zmax = 3.41 (theta = 0.10), and Zmax = 3.25 (theta = 0.15) respectively were obtained with the markers D9S118, D9S121, and ASS, located on chromosome 9q34-qter, suggesting that the causative gene in this family may lie on the long arm (q) of chromosome 9. CONCLUSIONS: These data indicate that the gene responsible for the phenotype in this kindred is located on chromosome 9 q. These data, together with evidence that a murine deafness gene is located in a syntenic area of the mouse genome, should direct the research community to consider this area as a candidate region for retinopathy and/or deafness genes.  相似文献   
160.
We have synthesized a novel six-coordinate metal chelator from the triamine cis-1,3,5-triaminocyclohexane by the addition of a 2-pyridylmethyl pendant arm on each nitrogen, which we term tachpyr. The experiments described here were designed to explore whether this compound exhibits potential antitumor activity. When added to MBT2 or T24 cultured bladder cancer cells, tachpyr was profoundly cytotoxic, with an IC50 of approximately 4.6 micromol/L compared with 70 micromol/L for desferioxamine. To explore the mode of action of tachpyr, several metal complexes were prepared, including Fe(II), Ca(II), Mn(II), Mg(II), Cu(II), and Zn(II) tachpyr complexes. Of these, the Zn(II), Cu(II), and Fe(II) complexes were without toxic effect, whereas the Ca(II), Mn(II), and Mg(II) complexes remained cytotoxic. To further probe the role of Zn(II) and Cu(II) chelation in the cytotoxicity of tachpyr, sterically hindered tachpyr derivatives were prepared through N-alkylation of tachpyr. These derivatives were unable to strongly bind Fe(III) or Fe(II) but were able to bind Zn(II) and Cu(II). When added to cells, these sterically hindered tachpyr derivatives were nontoxic, consistent with a role of iron depletion in the cytotoxic mechanism of tachpyr. Further, the addition of tachpyr to proliferating cultures resulted in an early and selective inhibition of ferritin synthesis, an iron storage protein whose translation is critically dependent on intracellular iron pools. Taken together, these experiments suggest that tachpyr is a cytotoxic metal chelator that targets intracellular iron, and that the use of tachpyr in cancer therapy deserves further exploration.  相似文献   
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