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71.
职业精神是从业者在职业活动中表现出来的价值取向,护理是一种直面生命、体现生命关怀的事业,护士的职业精神直接关系着人类的生命健康和护理事业的发展。生命意识的失落是当前护理职业精神中的突出问题。如何使护士理解职业精神的生命品性,以敬畏生命、解放患者、充满人文关怀的精神为职业操守,通过文化熏染、理念内化和实践积累,提升护士生命关怀能力,才能建构有利于护理事业发展的职业精神。  相似文献   
72.
The highest concentration of oak species in the world occurs in Mexico, but human activities have strongly degraded these oak forests. Mexican oaks have high economic, social, and cultural value, and restoring these forests is of paramount importance for the people of Mexico. Here, we propose a method for restoring oak forests using native shrubs that colonize degraded areas as nurse plants for oak seedlings. To test the viability of this proposal, seedling transplant experiments were performed in a degraded area near a protected oak forest relict. Two pioneer shrubs were identified as potential nurse species: Mimosa luisana and Senecio sp. The target oak species was Quercus castanea . Oak seedlings were located beneath the canopies of both shrubs and in the surrounding area without shrub cover. Water is a limiting resource for oak establishment in seasonally dry environments; therefore, we included irrigation systems in our experimental design to determine whether the combination of nurse plants plus watering led to higher rate of survival than the presence of nurse species alone. Seedling survival without watering was less than 20% both beneath nurse species and in the surrounding habitat. When water was supplied, survival rate beneath nurse species increased up to 58% while survival in the surrounding habitat did not differ from that observed in treatments without watering. Our results indicate that survival rate of oak seedlings is increased by the presence of nurse plants only when water is supplied. This suggests that restoration of oak forests in these degraded areas requires both nurse plants and watering.  相似文献   
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Aims Positive interactions are defined as non-trophic interactions where at least one of the interacting species is benefited in terms of fitness and the other remains unaffected. Nevertheless, the bidirectional feedbacks between species may be positive, neutral or negative. Thus, if facilitated species induce negative effects on their 'nurses', the assumed definition of positive interactions could be reconsidered.Methods We assessed if ecological interactions between cushions of Azorella madreporica and their facilitated species are positive. Specifically, we tested if cover of facilitated species has any costs for cushion plants from an ecophysiological perspective, and if these costs increase with the amount of cover of facilitated species. In addition, through pathway analysis and correlations, we assessed if cover and richness of facilitated species have a direct and/or indirect effect on the fitness of cushion plants.Important findings We found that facilitated plant species induced a significant cost for their nurses (cushion plants), and this cost increases with cover of the facilitated species. Additionally, the facilitated species exert a strong direct negative effect on the cushion's fitness and a moderate indirect negative cost evident through the nutrient status and physiological performance of cushion plants. We thus contribute evidence that positive interactions between high mountain cushion plants of central Chile and their 'facilitated' species may be an artifact more than a fact, especially when bidirectional effects are considered; contrasting with the majority of studies that document only one side of the interaction.  相似文献   
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Evolutionary rearrangements of pericentromeric heterochromatin among Drosophila melanogaster subgroup species have been investigated. A region-specific DNA library from Drosophila orena ovarian nurse cell chromocenter was obtained by the microdissection of polythene chromosomes. The probe has been localized on chromosomes of ovarian nurse cells of Drosophila melanogaster subgroup species using fluorescent hybridization in situ. Sequences homologous to the sequences of the DNA probe were detected in the chromocenter and pericentromeric regions of D. orena polythene chromosomes, in all pericentromeric regions of other species with several exceptions. There was no labeling on one of the arms of the D. simulans chromosome 2; however, these sequences were present on the telomere of D. erecta chromosome 3 and in regions adjacent to the brightly DAPI-stained heterochromatin blocks of D. yakuba, D. santomea and D. teissieri chromosomes 2 and 3. At the S6 stage (secondary reticulate nucleus), labeled chromatin can be found mostly within a restricted territory in D. orena nucleus; no such chromatin can be detected throughout the rest of the nucleus. On the contrary, at this stage, in nuclei of other species, labeled DNA is spread diffusely.  相似文献   
77.
Objectives To confirm the feasibility of nurse practitioner interventionin non-high-risk patients with recent myocardial infarction (MI). Design Observational study. Setting Acute coronary care unit in a teaching hospital. Methods We performed an open-label feasibility study to identify non-high-risk MI patients and evaluate the outcome of a new nurse practitioner intervention programme. The initial pilot phase served to identify the non-high-risk population. In the subsequent confirmation phase, 500 consecutive non-high-risk post-MI patients with preserved LV function without heart failure were included to receive nurse practitioner management. The nurse practitioner intervention started on transfer from the coronary care unit to the cardiology ward and continued thereafter for up to 30 days. Main outcome measures Time to first event analysis of death from all causes or repeat myocardial infarction. Results 500 Patients without signs of heart failure or depressed LV function were identified as nonhigh- risk and eligible for inclusion in the nurse practitioner intervention programme. In the implementation phase, none of the patients died and 0.9% developed a repeat myocardial infarction after 30 days of follow-up. Compared with the pilot phase, patients in the implementation phase spent fewer days in hospital (mean 11.1 versus 6.2 days; p<0.001). Conclusion It is feasible to identify non-high-risk post-MI patients, who can be managed adequately by a nurse practitioner. Embedding experienced nurse practitioners within critical care pathways may result in significant decreases in length of hospital stay. (Neth Heart J 2009;17:61-7.)  相似文献   
78.
Riparian vegetation has great functional importance in agroscapes because it establishes physical connections between natural ecosystems embedded in an agricultural matrix. Throughout the tropics, the historical demand for cropland and pastures in the lands adjacent to streams has led to the replacement of forests by exotic grasses. In order to find new methods for initiating the restoration of riparian forests, we evaluated the use of the pioneer shrubs Tithonia diversifolia and Piper auritum as nurse species for their effects on (1) competition with dominant grasses; (2) natural regeneration and the ecological facilitation of six native tree species of different successional stages; and (3) influence on microclimate. Over a period of 15 months, 4.4% coverage of P. auritum was insufficient to inhibit grasses. In contrast, 81% coverage of T. diversifolia limited the growth of dominant grasses such as Cenchrus purpureus, Paspalum paniculatum, and Cynodon plectostachyus likely by intercepting more than 90% of photosynthetically active radiation (PAR), even though other factors cannot be ruled out. T. diversifolia showed simultaneous effects of facilitation and competition by promoting higher survival of the planted native trees while slowing the growth of pioneer species and inhibiting the regeneration of native woody plants probably as a result of high light interception. This study suggests that planting T. diversifolia as a nurse shrub may facilitate early stages of restoration by inhibiting the growth of pastures, but requires pruning, both to increase light availability and promote the growth of planted trees and the recruitment of woody plants.  相似文献   
79.
Abstract The survival of Aspidosperma quebracho‐blanco juveniles in the Arid Chaco is facilitated under the canopy of nurse plants. The possible effects of nurse plants were studied at intra‐ and interspecific levels by analysing the spatial distribution of juveniles and adults of A. quebracho‐blanco, of the main shrubs Larrea divaricata and Mimozyganthus carinatus, and of the group of deciduous and evergreen shrub species, and their pair associations. Data were analysed using the SADIE (Spatial Analysis by Distance Indices) software. A. quebracho‐blanco seedling abundance followed the distribution pattern of the main shade‐providing species: an aggregated spatial distribution pattern in most of the categories studied. The seedling bank of A. quebracho‐blanco also showed an aggregated pattern and was spatially associated with shrubs and adults of its own species. The intensity of the association depended on the functional types: deciduous Fabaceae, deciduous non‐Fabaceae, evergreen and conspecific adults, each of which provides a different canopy structure and therefore different amounts of shade. The spatial association was significant with the evergreen group, and less significant with the deciduous Fabaceae group. There was no positive association with deciduous non‐Fabaceae, or with gaps (open sky). The differences generated by canopy cover may influence the nurse effect, as observed in the intensity of association of A. quebracho‐blanco with shrubs and conspecific adults.  相似文献   
80.
Common techniques currently used for afforestation in the Mediterranean basin consider the pre‐existing vegetation (mainly shrubs) as a source of competition for trees, and consequently it is generally eliminated before planting. Nevertheless, it has been demonstrated that woody plants can facilitate the establishment of understory seedlings in environments that, like the Mediterranean area, are characterized by a pronounced dry season. In this study, we experimentally analyze the usefulness of shrubs as nurse plants for afforestation of two native conifers, Pinus sylvestris L. (Scots pine) and Pinus nigra Arnold (black pine). Two‐year‐old seedlings were planted in four microhabitats: (1) open interspaces without vegetation (which is the usual method used in afforestation programs), (2) under individuals of Salvia lavandulifolia, (3) under the north side of spiny shrubs, and (4) under the south side of spiny shrubs. Pine survival was remarkably higher when planted under individuals of the shrub S. lavandulifolia (54.8% for Scots pine, 81.9% for black pine) compared with open areas (21.5% for Scots pine, 56.8% for black pine; chi square, p < 0.05). The survival of both pines was also higher when planted on the north side of spiny shrubs, although the survival on the south side was similar to that found in open areas. In addition, pine growth was not inhibited when planted in association with shrubs. This pattern appears to result from the combination of abiotic conditions imposed by the presence of a nurse shrub, which leads to improvement in seedling water status and therefore reduced summer mortality by drought. The results show that the use of shrubs as nurse plants is a technique that offers both economic and ecological advantages, in terms of savings in labor and plant material and reduced and even negligible impact on the pre‐existing vegetation.  相似文献   
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