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51.
Epidemic outbreaks of group B meningococcal disease exhibit a clonal nature consisting of a common serotype-subtype. Subtype-specific monoclonal antibodies (MAbs) directed toward two variable regions (VR1 and VR2) of the class 1 protein of Neisseria meningitidis are used in this classification scheme. A new MAb was developed to classify a nonsubtypeable (NST) strain of N. meningitidis, 7967. This MAb bound to both the NST strain and the prototype subtype P1. 14 strain, S3446, by dot blot analysis. However, a MAb produced to the prototype P1.14 strain did not bind to strain 7967. Sixteen additional strains were further identified as P1.14 with the prototype MAb; of these, 15 strains bound both MAbs. Differences in the characteristics of binding of both antibodies to the three apparently diverse P1.14 strains were studied further by using outer membrane complex proteins, immobilized peptides, and soluble peptides. Deduced amino acid analysis suggested that both MAbs bind to VR2 and that single amino acid changes within VR2 (KM, NM, or KK) might explain the differences in binding characteristics. These results demonstrated that minor variations which exist within subtype variable regions may be clearly identified only by a combination of molecular and immunologic testing. The impact of subtype variation will become more evident as subtype-specific vaccines are developed and tested for efficacy.  相似文献   
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An algorithm and a personal computer program for automatic distinguishing between EEC records containing evoked and no potentials, based on the detected invariants reflecting experts' experience in evoked potential analysis have been developed. The efficiency of the programme (its high accuracy and speed, low volume) has been demonstrated in the system for automatic determination of the hearing level by long-latent evoked potentials. It is easily modifiable to identify evoked potentials from other modalities (visual, somatosensory ones) in the systems using the traditional and/or up-to-date computerized EEC equipment.  相似文献   
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The relationship between a range of prenatal and perinatal events and risk for psychopathology in offspring was examined. Prenatal and perinatal events investigated included maternal experiences, health, and substance use during pregnancy, obstetric complications, feeding practices, and infant health during the first year of life. Offspring diagnosis was based on structured interviews conducted with 579 adolescents on two occasions. Risk for later psychopathology was associated with a number of prenatal and perinatal factors. Major depression was associated with not being breast fed and maternal emotional problems during the pregnancy. Anxiety was chiefly associated with fever and illness during the first year of life and maternal history of miscarriage and stillbirth. Disruptive behavior disorder was associated with poor maternal emotional health during the pregnancy and birth complications. Risk for substance use disorder was associated with maternal use of substances during the pregnancy. Mediating effects of maternal depression, maternal-child conflict, and physical symptoms in the child, and moderating effects of gender of child and parental education were also evaluated. The limitations of this study are discussed and future research directions are suggested.  相似文献   
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Since the rapid expansion of managed care coupled with dramatic reductions in lengths of inpatient stay, there is widespread concern that the emphasis on cost containment is eclipsing attention to patient care. The present study was undertaken to evaluate speculations that the majority of short-stay (less than 48 hours) admissions to a psychiatric inpatient service at a large teaching hospital in the midwestern United States consisted of public pay patients who were rapidly transferred to area state hospitals. Using two cases mix measures, severity of illness and changes in acuity and clinical outcomes of a sample of short-stay (n = 77) and longer stay (n = 145) admissions were compared. Short-stay admissions, although similar to longer stay patients in terms of demographics, Axis I diagnosis, payer status, and appropriateness of admission, are clinically distinct. The use of nonhospital alternatives in treating a subsample of suicidal patients and the implications for improved mental health services delivery are discussed.  相似文献   
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The diffusive release from hydrogels can be determined by both composition and geometry. This paper presents a theoretical and experimental comparison of the release characteristics of proxyphylline in water-swollen slabs, spheres, and cylinders of a urethane cross-linked poly(ethylene oxide). Contrary to general conventional wisdom it was found that practically cylinders and spheres, which have considerable potential advantages for oral delivery, can provide good 'anomalous' rates for which the 'exponent of release' into water from the dry xerogels is c. 0.8 compared with 1.0 for zero order. An exponent of 0.94 was found for release into water from 'larger' xerogel flat slabs thus confirming that these configurations can provide essentially constant delivery formulations from which the active agent cannot be 'dumped'. For up to 40% total drug release, the theoretical release profiles were essentially of identical form for all three geometries in the swollen state and, as expected in theory and practice, showed an exponent for release of close to 0.5. However, the experimental release of proxyphylline was found to be more sustained from swollen spheres of these polymers than theory would predict. The half life times for release were further extended by approximately two and a half times for the initially dry devices compared with the initially swollen ones.  相似文献   
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PURPOSE: This retrospective study was undertaken to review the clinical signs and management of patients with perforating eye injuries associated with regional anaesthesia for ophthalmic surgery. METHODS: Fifteen consecutive patients presenting with inadvertent perforation of the globe were evaluated. Eleven required vitreoretinal surgery. The indications were retinal detachment (six eyes), vitreous haemorrhage (four) and an epiretinal membrane (one eye). RESULTS: Those eyes with retinal detachments generally had a poor functional outcome in spite of the retinae being attached in five of the six eyes. The operative findings of those eyes with vitreous haemorrhage but attached retina demonstrated varying retinal tear configurations. CONCLUSIONS: Eyes with perforating injuries following intraorbital anaesthesia are at risk of developing a retinal detachment. In those eyes presenting with dense vitreous but attached retina, consideration of vitrectomy and laser photocoagulation is advised.  相似文献   
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The authors used a directed-forgetting task to investigate whether psychiatrically impaired adult survivors of childhood sexual abuse exhibit an avoidant encoding style and impaired memory for trauma cues. The authors tested women with abuse histories, either with or without posttraumatic stress disorder (PTSD), and women with neither abuse histories nor PTSD. The women saw intermixed trauma words (e.g., molested), positive words (e.g., confident), and categorized neutral words (e.g., mailbox) on a computer screen and were instructed either to remember or to forget each word. Relative to the other groups, the PTSD group did not exhibit recall deficits for trauma-related to-be-remembered words, nor did they recall fewer trauma-related to-be-forgotten words than other words. Instead, they exhibited recall deficits for positive and neutral words they were supposed to remember. These data are inconsistent with the hypothesis that impaired survivors exhibit avoidant encoding and impaired memory for traumatic information.  相似文献   
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