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991.
S Chan SS Chin K Kartha DR Nordli RR Goodman TA Pedley SK Hilal 《Canadian Metallurgical Quarterly》1996,17(9):1725-1731
PURPOSE: To investigate the phenomenon of reversible increased signal intensity of medial temporal lobe structures and cerebral neocortex seen on MR images of six patients with recent prolonged seizure activity. METHODS: After excluding patients with known causes of reversible signal abnormalities (such as hypertensive encephalopathy), we retrospectively reviewed the clinical findings and MR studies of six patients whose MR studies showed reversible signal abnormalities. MR pulse sequences included T2-weighted spin-echo coronal views or conventional short-tau inversion-recovery coronal images of the temporal lobes. RESULTS: All six MR studies showed increased signal intensity within the medial temporal lobe, including the hippocampus in five studies. All follow-up MR examinations showed partial or complete resolution of the hyperintensity within the medial temporal lobe and the neocortex. In one patient, results of a brain biopsy revealed severe cerebral cortical gliosis. Temporal lobectomy performed 4 years later showed moderate cortical gliosis and nonspecific hippocampal cell loss and gliosis. CONCLUSION: Significant hyperintensity within the temporal lobe is demonstrable on MR images after prolonged seizure activity, suggestive of seizure-induced edema or gliosis. Damage to medial temporal lobe structures by prolonged seizure activity indicates a possible mechanism of epileptogenic disorders. 相似文献
992.
This investigation explored differences in motivational beliefs of 154 Asian American and 372 non-Asian 9th graders. Students completed surveys indicating their academic beliefs and later responded to a novel task to assess their achievement behavior. The difference in type of beliefs between the two groups explained, in part, their achievement behavior. Asian American students' fear of the consequence of academic failure best explained their performance. However, this variable least explained the results for non-Asian students. Asian American students reported lower levels of self-efficacy beliefs, yet significantly outperformed their non-Asian counterparts on the task. The fear of academic failure better explained achievement motivation for Asian Americans than did self-efficacy beliefs. A major implication of this investigation is that motivational beliefs elicit different responses in different cultural–ethnic groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
RA Majack NA Grieshaber CL Cook MC Weiser RC McFall SS Grieshaber MA Reidy CF Reilly 《Canadian Metallurgical Quarterly》1996,167(1):106-112
Health promotion is gaining widespread recognition throughout the world as the most efficacious practice in achieving health for all. In Canada, the philosophy of health promotion is driving both federal and provincial health initiatives. Such a philosophy is derived from a human science paradigm and is in direct opposition to the natural science paradigm from which the biomedical approach to health care emerged. There now exists a tension between these contrasting paradigms as health care shifts to embrace a health-promotion perspective. The nursing process is based in the natural science paradigm and on a biomedical approach to health care. In order for nurses to embrace health promotion fully, they must move away from the philosophy of the natural sciences and adopt a human science perspective. Such a shift requires a radical transformation in nursing practice as nurses move away from the 'top-down' approach of the nursing process and adopt a 'bottom-up' approach to health-promoting nursing practice. The purpose of this paper is to compare and contrast the nursing process with the principles of health promotion, and to challenge our use of the nursing process in current nursing practice. In particular, a framework for health-promoting nursing practice will be provided. 相似文献
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995.
It is thought that the posterior expression of the 'selector' genes engrailed and invected control the subdivision of the growing wing imaginal disc of Drosophila into anterior and posterior lineage compartments. At present, the cellular mechanisms by which separate lineage compartments are maintained are not known. Most models have assumed that the presence or absence of selector gene expression autonomously drives the expression of compartment-specific adhesion or recognition molecules that inhibit intermixing between compartments. However, our present understanding of Hedgehog signalling from posterior to anterior cells raises some interesting alternative models based on a cell's response to signalling. We show here that anterior cells that lack smoothened, and thus the ability to receive the Hedgehog signal, no longer obey a lineage restriction in the normal position of the anterior-posterior boundary. Rather these clones extend into anatomically posterior territory, without any changes in engrailed/invected gene expression. We have also examined clones lacking both en and inv; these too show complex behaviors near the normal site of the compartment boundary, and do not always cross entirely into anatomically anterior territory. Our results suggest that compartmentalization is a complex process involving intercompartmental signalling; models based on changes in affinity or growth will be discussed. 相似文献
996.
SN Ameratunga RN Norton SW MacMahon GS Smith RT Jackson R Currie JD Langley SS Sharpe A Cheng DG Woodfield 《Canadian Metallurgical Quarterly》1998,22(5):578-582
Blood donors have made important contributions to research, most notably in cross-sectional seroprevalence studies. The proposed New Zealand Blood Donors Health Study is a prospective cohort study of 30,000 New Zealand donors designed to investigate the determinants of common injuries, cardiovascular disease and cancer. While robust from an analytic perspective, the execution of prospective cohort studies in many settings is impeded by methodological, economic and organisational barriers. We examined the operational considerations of implementing a large-scale cohort study at a transfusion centre and evaluated measures taken to optimise data collection procedures. A pilot study of 1,000 participants revealed donor motivation to participate in this research was high (91% response rate). Comprehensive exposure data on lifestyle, behavioural and psychosocial factors were obtained from 95% of participants. Substantial heterogeneity in levels of potential risk factors was noted among respondents. Detailed dietary habit information and a study blood sample were obtained from 67% and 100% of participants, respectively. Study recruitment and baseline data collection was feasible during routine donor visits with minimal interruption to donor centre staff and procedures. We conclude the study design and characteristics of the regional donor program enhance the efficiency and significance of the proposed research. 相似文献
997.
998.
999.
AN Inozemtsev SS Trofimov GG Borlikova FA Firova LL Pragina TA Gudasheva RU Ostrovskaia NA Tushmalova TA Voronina 《Canadian Metallurgical Quarterly》1998,61(3):10-12
Endothelium protector SOFTEL is developed by Ekran firm and Institute of Eye Diseases, Russian Academy of Medical Sciences. The drug was used in 157 patients aged 28-79 years. Perforating keratoplasty for corneal leukoma and keratoconus was carried out in 46 patients, cataract extraction with implantation of intraocular lens (IOL) in 94, and cataract extraction without IOL implantation in 17 patients. Two patients developed slight hypertension in the postoperative period, which resolved within 24 h, and four patients developed moderate corneal edema persisting for 1-2 days postoperation. The protective effect of softel is compatible with that of its foreign analog Healon. The drug is effective in cataract extractions with IOL implantation and perforating keratoplasty. 相似文献
1000.
KK Nobuhara ML Ferretti AM Siddiqui SS Kim ST Treves JM Wilson 《Canadian Metallurgical Quarterly》1998,33(7):1024-8; discussion 1028-9
BACKGROUND/PURPOSE: We have demonstrated previously that postnatal lung growth can be accelerated by continuous intrapulmonary distension with perfluorocarbon (PFC). The purpose of this study was to examine the effect of PFC distension on long-term lung function and to determine if shorter periods of lung distension would be sufficient to stimulate growth. METHODS: Eight neonatal lambs underwent a right thoracotomy. The superior segment of the right upper lobe of the experimental group (n = 5) was isolated and distended with PFC to an intrabronchial pressure of 7 to 10 mm Hg. The inferior segment was removed. After a 7-day distension period (the maximum period of exposure currently allowed for humans), the experimental animals underwent removal of the intrabronchial catheter and surgical closure of the bronchial stump. Control animals (n = 3) underwent right upper lobe inferior segmentectomy alone. Animals were allowed to breathe spontaneously and reach 3 to 6 months of age. Before death, all animals were evaluated by chest radiographs and ventilation-perfusion scans. Pulmonary venous blood gas levels were obtained. Lungs were harvested and airway fixed for morphometric analysis. RESULTS: Chest radiographs of the experimental group showed variable amounts of intrapleural and interstitial PFC but were otherwise normal. Results of ventilation/perfusion (VQ) scans of all experimental animals were normal. On retrieval, the right upper lobe of experimental animals appeared slightly hyperinflated compared with controls. Right upper lobe pulmonary vein PaO2 to left pulmonary vein PaO2 ratio was comparable in experimental and control animals (1.2 +/- .41 v 0.92 +/- .15). DNA to protein ratios were slightly higher in the right upper lobes of experimental animals, however, the difference was not statistically significant (.64 +/- .11 v .42 +/- .03). On histological evaluation, the airway epithelium and alveoli of the right upper lobe of experimental animals appeared normal. Lung morphometry results showed no statistically significant differences in alveolar number between experimental and control animals. CONCLUSIONS: From these preliminary data we conclude that (1) lung architecture is preserved in juvenile animals subjected to intrapulmonary PFC distension as neonates, (2) lung function is preserved in the lobar segment after PFC distension, and (3) intrapulmonary PFC distension appears to be safe at 3 to 6 months follow-up. However, 7 days of PFC distension is insufficient to promote lung growth. 相似文献