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51.
52.
A better understanding of the factors related to cancer helps health professionals like nurses to provide more individualized health care which will affect the prognosis of patients with ovarian cancer The aim of this study was to analyze the association of clinicopathological features and risk factors with ovarian cancer prognosis. This retrospective study recruited 103 patients with ovarian cancer who were treated at a single institution during the period from May 2002 to May 2014. The blood markers CA125, CA153, and serum ferritin (SF) were detected in all patients before surgery. Risk factors were analyzed using univariate and multivariate logistic regression models and survival analyses were performed using Kaplan–Meier. Menopause was considered to be associated with SF expression levels. The expression of CA125, CA153, and SF were associated with metastasis and FIGO stage. The expression of CA153 was associated with tumor grade. FIGO stage, menopause, expression levels of CA125 and CA153 are associated with poor prognosis in ovarian cancer patients. Through what we have found, nurses should pay attention to these prognostic factors in order to provide optimal nursing care and improve the quality of life of patients with ovarian cancer.  相似文献   
53.
Background and AimsPlants in dry Mediterranean mountains experience a double climatic stress: at low elevations, high temperatures coincide with water shortage during summer, while at high elevations temperature decreases and water availability increases. Cushion plants often act as nurses by improving the microclimate underneath their canopies, hosting beneficiary species that may reciprocally modify their benefactors’ microenvironment. We assess how the nurse cushion plant Arenaria tetraquetra subsp. amabilis adjusts its hydraulic system to face these complex abiotic and biotic constraints.MethodsWe evaluated intra-specific variation and co-ordination of stem xylem anatomy, leaf functional traits and plant architecture in response to elevation, aspect and the presence of beneficiary species in four A. tetraquetra subsp. amabilis populations in the Sierra Nevada mountains, southern Spain.Key ResultsXylem anatomical and plant architectural traits were the most responsive to environmental conditions, showing the highest mutual co-ordination. Cushions were more compact and had smaller, more isolated conductive vessels in the southern than in the northern aspect, which allow minimization of the negative impacts of more intense drought. Only vessel size, leaf mass per area and terminal branch length varied with elevation. Nurse cushions co-ordinated plant architecture and xylem traits, having higher canopy compactness, fewer leaves per branch and fewer, more isolated vessels than non-nurse cushions, which reflects the negative effects of beneficiary plants on nurse water status. In non-nurse cushions, plant architecture co-ordinated with leaf traits instead. The interacting effects of aspect and elevation on xylem traits showed that stress due to frost at high elevation constrained xylem anatomy in the north, whereas stress due to drought had a parallel effect in the south.ConclusionsTrait co-ordination was weaker under more demanding environmental conditions, which agrees with the hypothesis that trait independence allows plants to better optimize different functions, probably entailing higher adjustment potential against future environmental changes.  相似文献   
54.
The growth-promoting effects of nurse cells of carrot, tomato, patato, maize, bean, carnation and two species of tobacco were studied on carrot, tomato, tobacco and potato cells plated at low densities. In an area immediately below the nurse cells the plating efficiency was very high and found to be independent of cell density. In an area outside the nurse cells, in some cases, the plating efficiency tended to be much higher in combinations with cells from a heterologous source as compared with those from a homologous source. Moreover, in the same area with some combinations the plating efficiency decreased when cell density was lowered, while with other combinations this phenomenon did not occur. This decrease was independent of the absolute value of plating efficiency. In experiments in which the concentration of conditioning factors was presumably changed, no significant difference in the plating efficiency was noticed. We therefore suggest that different plating efficiencies observed with heterologous nurse cells were not due to a higher level of conditioning factors, but rather to the production of different types of conditioning factors that are presumably degraded with different efficiency.  相似文献   
55.
Mesophyll protoplasts were isolated from leaves of in vitro grown patchouli (Pogostemon cablin Benth.). The protoplasts were encapsulated in alginate beads, approximately 2–3×103 protoplasts per 25 l bead. Successful colony formation was induced when the protoplast beads were inoculated into a liquid medium supplemented with 10-6 M NAA and 10-5 M BA. The frequency of colony formation was improved greatly by the inclusion of several beads per ml medium. To induce high colony formation for a single bead, it was essential to culture protoplasts in the presence of nurse beads containing actively-growing cells of the same species. Rapid regeneration of plants from protoplast-derived calluses was accomplished by a two-step culture procedure with liquid and then solid media. Gas-chromatographic analyses showed that regenerated plants produced an essential oil comprising a full-set of patchouli sesquiterpenes.Abbreviations BA 6-benzylaminopurine - 2,4-D 2,4-dichlorophenoxyacetic acid - f. wt. fresh weight - GC gas chromatography - MES 2-(N-morpholino)ethanesulfonic acid - NAA 1-naphthaleneacetic acid  相似文献   
56.
1 The clonal cactus Opuntia rastrera shows predominantly sexual reproduction in grasslands (GH) and clonal propagation in nopaleras (NH). We assessed the effects of light, herbivory, water availability and the habitat an offspring came from on the survival and growth of sexual or clonal offspring (i.e. seedlings and cladodes), through 3- and 4-year common garden and short-term greenhouse experiments.
2 Shading by nurse plants increased seedling survival in the field by an order of magnitude, and a small additional advantage due to predator protection by grasses was observed. Strong herbivory transforms a facultative nurse–protégé relationship for seedlings into an obligatory one.
3 In the greenhouse seedlings grew better under shade, but in the field the production of the first cladode was delayed in seedlings in the more shaded GH. Competition for soil resources may be more intense under a dense grass tussock than under a open shrub, thus affecting the nurse–protégé relationship. Seedling survival under nurse plants was similar in GH and NH, but higher plant cover suggests that a larger number of seedlings will establish in GH in the long term.
4 Cladode survival was higher in NH. Cladodes were more successful than seedlings at establishing in intercanopy areas, possibly due to physiological differences as well as their ability to survive partial predation. Cladode survival in intercanopy areas may explain the enhanced clonal propagation in the more open NH scrubland, together with their susceptibility to the flooding which affects GH.
5 The high seedling and cladode survival in the greenhouse experiments contrasted with that observed in the field, indicating that survival is determined by the interaction between herbivores, plants and abiotic conditions rather than the physiological aptitude of the plants.  相似文献   
57.
研究了谷子原生质体看护培养中的一些问题。结果表明:不同种植物愈伤组织做看护细胞对谷子原生质体培养植板率有不同的影响。用光头种草愈伤组织对谷子胚性、非胚性或中间型意伤组织的原生质体进行看护培养,以对胚性意伤组织原生质体的效果最好。看护培养主要是作用于原生质体形成完整细胞后的生长发育。试验没有观察到明显的看护细胞数量效应。  相似文献   
58.
Summary Primary callus of barley (Hordeum vulgare L.) derived from scutella (cv. Dissa) and anthers (cv. Igri) was used for protoplast isolation and plant regeneration. The protoplasts were embedded in agarose and cultured with nurse cells. The plating efficiency varied from 0.1% to 0.7%. Shoots regenerated from the developing callus. Plantlets were transferred to soil and cultivated in the greenhouse three to five months after protoplast isolation. All plants were normal in morphology, and most of them flowered and set seeds.  相似文献   
59.
The nucellus was removed from immature seeds of 4 mango genotypes, andcultured under different induction conditions. The mango genotypes includedpolyembryonic ‘Hindi’ and ‘Nam Doc Mai’ and monoembryonic ‘Lippens’ and’Tommy Atkins‘. Nucellar explants were cultured on modified B5 basal mediumunder the following inductive conditions: 1) 4.52 μM 2,4-D; 2) nogrowth regulator (control); 3) 4.52 μM 2,4-D + embryogenic ‘Parris‘nurse culture; 4) no growth regulator + embryogenic ‘Parris’ nurse culture.Induction of embryogenic competence was mediated by 4 factors: genotype,explanting, 2,4-D and the presence of a highly embryogenic nurse culture,although there was considerable difference in genotype response. ‘Hindi’ hadthe greatest embryogenic potential, followed by ‘Lippens’, ‘Tommy Atkins‘and ‘Nam Doc Mai’, respectively. Induction of embryogenic cultures of allgenotypes at low frequency occurred as a result of explanting excisednucellus onto control medium. The most effective treatment for inducingembryogenic cultures was 2,4-D + embryogenic ‘Parris’ nurse culture with’Hindi’, ‘Lippens’ and ‘Nam doc Mai’, with the exception of ‘Tommy Atkins’,in which the treatment with 2,4-D alone was most effective. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
60.
The growth of tree lupins was investigated in two experiments. In the first, two ages of plant, 4-wk-old seedlings and 1-year-old plants, were transplanted into a ryegrass sward in an upland environment. Growth, in terms of leaf production, branching and stem elongation, was measured over two successive growing seasons. Plant dry matter and nutrient contents were determined at the beginning and end of each growing season. In the first summer, the rate of production of new leaves on the main stem of seedling plants averaged 1.8 leaves per wk and main stem length increased from 5 to 67 cm. On older plants, where floral apices had been initiated on main and primary stems, there was a 3–10 fold increase in secondary branch length. In the second season, there was no effect of plant age on rates of leaf appearance or stem extension; dry matter production was higher than in the first season. In the second experiment, the effect of removal of 0%, 50% or 100% of fully expanded leaves on the subsequent growth of 23-wk-old plants was investigated. During the 7-wk growth period, defoliation promoted the rate of production of mature leaves, and area and dry weight of new laminae were slightly higher in defoliated plants. Defoliation did not affect the concentrations of N, P or K in the new laminae, but P and K concentrations in petioles of defoliated plants were significantly higher than those in intact plants. The results from the experiments are discussed in relation to the potential use of tree lupins as nurse species and biomass crops in hill and upland environments of the UK.  相似文献   
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