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81.
目的 探讨医院实施组织职业生涯管理对护士工作满意度的影响。方法 随机选取我市3所已实施护士组织职业生涯管理的医院中80名护士进行调查分析,比较实施护士组织职业生涯管理的效果以及管理后护士工作满意度改善情况结果 实验组护士的晋升公平评分、注重培训评分、提供职业信息、促进职业自我发展及总评分均显著高于对照组,差异具有有统计学意义(P<0.05);实验组护士内在满意度评分、外在满意度评分及总满意度评分均显著高于对照组,差异具有有统计学意义(P<0.05)。结论 实施护士组织职业生涯管理能有效提高护士的工作满意度,有利于促进护士的职业生涯发展及提高护理管理质量。  相似文献   
82.
对中国红豆杉〔Taxus chinensis(Pilger)Rehd.〕、云南红豆杉(T. yunnanensis Cheng et L.K.Fu)和东北红豆杉(T. cuspidata Sieb.et Zucc.)不同部位的愈伤组织进行培养及分析比较。结果表明,中国红豆杉愈伤组织生长较快,其叶片诱导的愈伤组织紫杉醇含量较高,且紫杉醇含量与培养物的外观特征有明显相关性,颜色浅、块状或颗粒较明显的细胞团紫杉醇含量较高。运用细胞看护培养技术,从中国红豆杉愈伤组织中筛选出生长速率达0.52g.L-1.d-1、紫杉醇含量超过0.01%的细胞优株,经20次继代培养,其生长和紫杉醇含量均较稳定。  相似文献   
83.
目的 旨在探讨护士长的领导行为和医院护理安全文化的关系。方法 采用便利抽样的方法对黑龙江省3所三级甲等中医院的344名护士进行了多元化护士长领导行为、护理安全文化的调查。调查所得数据全部输入SPSS17.0软件进行分析,最后得出结论。结果 护士长领导行为得分最高为领导魅力,其次为被动例外管理、个性化关怀、主动例外管理、感召力、权变奖赏、智能激发。护理安全文化总体稍高于中等水平,其中团队氛围、对工作的满意度、单位安全的氛围、对管理的感受高于中等水平,对压力的认知得分低于中等水平。结论 护士感知的护士长领导行为各维度与护理安全文化各维度之间具有正相关。  相似文献   
84.
The ultrastructure of the ovary of Milnesium tardigradum during early vitellogenesis is described. Within the ovary, there were large multinuclear cells surrounded by many mononuclear oocytes. Observation of serial sections revealed four multinuclear cells that were connected to each other by cytoplasmic bridges. Each peripheral oocyte was connected to the multinuclear cell. An enormous ER-like structure was conspicuous in the centre of the multinuclear cell. The presence of large numbers of lipid droplets and yolk granules in both multinuclear cells and many mononuclear oocytes suggested a role as nurse cells. A small number of these oocytes grow to be eggs. The structural features of the multinuclear nurse cell were compared with other known examples.  相似文献   
85.
Morphology is strongly correlated with trophic mode in marine invertebrate larvae. We asked if larval morphogenesis is influenced by adelphophagy, a trophic mode in which larvae are provisioned with additional yolk in the form of extra‐embryonic nurse eggs, instead of the more common increase in egg size. We used histology and scanning electron microscopy to analyze morphogenesis in Boccardia proboscidea, a polychaete that produces both small planktotrophic larvae and large adelphophagic larvae in a single egg capsule. Results indicate that both morphs are similar for histogenesis of ectodermal derivatives, and differ for the gut mucosa and coelom which show delayed differentiation in the adelphophagic morph. Heterochrony in gut and coelom development suggests that differentiation of these organ systems is decoupled from overall development, and that a trade‐off exists between maturation of these tissues and rapid growth. We also looked for potential barriers to adelphophagy in planktotrophic larvae that have nurse eggs available to them. These planktotrophic larvae appeared morphologically equipped for adelphophagy: the gut was differentiated at an early stage, and larvae had structures involved in nurse‐egg ingestion in the adelphophagic morph (e.g., oral cilia and ventral ciliated patches). Planktotrophic larvae were additionally capable of ingesting particles (Di‐I) while in the egg capsule. Lack of adelphophagy in planktotrophic larvae remains enigmatic but these results indicate that morphology alone does not account for the arrested development shown by these larvae. J. Morphol. 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
86.
The role of facilitation in the structuring of plant communities has been often demonstrated in environments under high abiotic stress, especially in semi‐arid and arid ecosystems and high elevations. Few studies, however, analysed facilitation in systems that are highly productive and rich in species, which are thought to be theoretically unlikely to demonstrate strong effects of facilitation. Here, we investigate the importance of Eryngium horridum, a rosette species, on the maintenance of plant diversity in subtropical grasslands in southern Brazil. We evaluated facilitation in areas under two different types of management: abandonment and grazing. Plots were established in areas with and without individuals of E. horridum and all species were identified and had their cover estimated. The Relative Neighbour Effect index was calculated in order to verify the presence of competition or facilitation. Our results indicated facilitation in both abandoned and in grazed grasslands, but apparently through different mechanisms. In the first case, the plant's architecture opens the canopy and allows more light to reach small forbs in the grass matrix. In the second case, E. horridum appears to protect more palatable species from herbivores. Otherwise considered an obnoxious species, E. horridum plays an important ecological role in subtropical grasslands in southern Brazil by facilitating other species and consequently, increasing local richness. Areas with this rosette species are important sources of diaspores, which are able to colonize new open sites and thus, maintain biodiversity.  相似文献   
87.
88.
In the present study, we describe the features of programmed cell death of the ovarian nurse cells occurring during vitellogenesis of the silkmoth Bombyx mori. At developmental stage 5, the nurse cells occupy one-half of the follicular volume and obtain a rather spherical shape, while the nurse cell nuclei appear large and elongated, forming impressive projections. At the following stage, stage 6, the nurse cells decrease in size and their shape becomes elliptic. The nuclei remain elongated, being also characterized by large lobes. The lobes of the ramified nurse cell nuclei seem to retain the nucleus in the center of the cell during the dumping of the nurse cell cytoplasm into the growing oocyte. At stage 7, membrane enclosed vacuoles can be easily detected into the nurse cells cytoplasm. Ultrastructural analysis and fluorescent microscopy using mono-dansyl-cadaverine staining of these vacuoles also reveal that they represent autolysosomes. Caspase activity is detected during stage 7, as it is demonstrated by using the Red-VAD-FMK staining reagent. At developmental stages 8 and 9, the nurse cells exhibit chromatin condensation, DNA fragmentation and caspase activity. Finally, during the following stage 10, the nuclear remnants are assembled into apoptotic vesicles, which, after being phagocytosed, are observed in the cytoplasm of adjacent follicle cells. We propose that apoptosis and autophagy operate synergistically during vitellogenesis of B. mori, in order to achieve an efficient and rapid clearance of the degenerated nurse cell cluster.  相似文献   
89.
Objective: To describe the unique nursing responsibilities involved in providing nursing care to severely obese weight loss surgery patients and to develop evidence‐based guidelines for safe patient care. Research Methods and Procedures: We performed a systematic review of the scientific literature using MEDLINE and CINAHL. A specific search of nursing journals from 1985 to 2004 identified 134 articles; 16 were found to be pertinent. These were reviewed in detail and used in the context of this report. The quality of the evidence was graded according to a system derived from established evidence‐based models. Recommendations were developed from published evidence and expert opinion. Results: This Task Group found that safe and competent nursing care requires assessment of, and provision for, the complex physical and psychological needs of weight loss surgery patients. We developed evidence‐based guidelines for preoperative, perioperative, and postoperative care that address risk factors unique to severely obese patients. We also addressed issues related to the use of proper body mechanics and positioning to avoid on‐the‐job injury to nursing staff. Discussion: We found that patient safety is best served when nurses are specifically trained to deal with the physical, medical, and psychosocial needs of severely obese patients and when they play an integral role in the multidisciplinary healthcare team. This role should start with a patient's first contact with the system and continue through discharge and follow‐up. Special attention needs to be paid to the widespread bias and discrimination that severely obese individuals often experience.  相似文献   
90.
BACKGROUND AND AIMS: Most studies on cactus recruitment have focused on the role of woody plants as seedling facilitators. Although the spatial association of cacti with objects had been described, the mechanisms underlying this association remain unknown. The aims of this study were to identify which mechanisms facilitate the establishment of a columnar cactus under the shade and protection of objects and to compare these mechanisms with those involved in plant-plant facilitation. METHODS: Three split-split-plot field experiments were conducted to compare the effects of two microhabitats (inside rocky cavities and beneath plant canopies) on seed removal, germination, seedling survivorship and dry weight. Flat, open spaces were used as the control. For each microhabitat, the effect of seed or seedling protection and substrate limitation were explored; aboveground microclimate and some soil properties were also characterized. KEY RESULTS: The permanence of superficial seeds was greater inside rocky cavities than beneath woody plant canopies or on flat, open areas. Germination was similar in cavities and beneath plant canopies, but significantly higher than on flat, open areas. Seedling survivorship was greater beneath plant canopies than inside cavities or on flat, open spaces. CONCLUSIONS: The mechanisms of plant facilitation are different from those of object facilitation. There are seed-seedling conflicts involved in the recruitment of P. leucocephalus: nurse plants favour mainly seedling survivorship by providing a suitable microenvironment, while nurse objects mainly favour seed permanence, by protecting them from predators.  相似文献   
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