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21.
无患子当年生砧苗嫁接育苗技术 总被引:4,自引:0,他引:4
采用正劈接、短枝腹接、斜劈接、舌接等不同嫁接方法对无患子实生苗即移即接、移后10 d嫁接、地苗嫁接育苗试验,探索提高无患子嫁接成活率的途径。结果表明,用正劈接方法对无患子实生苗即移即接其嫁接成活率高,此嫁接技术可以在无患子嫁接育苗生产中应用。 相似文献
22.
Frozen lamellar corneal grafts and nictitating membrane flaps were used in 18 dogs and 12 cats to repair deep corneal defects. In all dogs either melting corneal ulcers or descemetoceles were present. In the 12 cats, nine had either a melting corneal ulcer or descemetocele, two animals had acute bullous keratopathy, and one cat had corneal sequestrum. Initial vascularization with gradual clearing of the graft occurred during the first 45 days postoperatively. At 60 days postoperatively, all eyes were visual. Frequent postoperative complications included: focal dehiscence of the wound ( n = 9); melting of part of the graft ( n = 7); and pigmentation of the graft ( n = 4). The frozen lamellar corneal graft was a very safe technique, and restored the tectonic and the optical function of the cornea. It provided the best results in corneas with nonperforating corneal defects. This technique provides poorer results when the cornea was perforated prior to surgery or during the surgical procedure. 相似文献
23.
H. Delatte H. Holota B. Reynaud J. Dintinger 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(3):245-253
Two wild genotypes from the same species Lycopersicon pimpinellifolium, WVA106 (susceptible) and INRA-Hirsute (so-called ‘resistant’), were compared with respect to their reaction to Tomato yellow leaf curl virus isolate Réunion (TYLCV-Mld[RE]), using both whitefly-mediated inoculation and graft inoculation. Disease incidence and symptom
severity were scored. Presence and quantification of viral DNA were assessed by dot blot hybridisation. Upon insect inoculation,
accession INRA-Hirsute showed a moderate resistance against TYLCV that was overcome by a high inoculation pressure obtained
by increasing the cumulative number of inoculative whiteflies. Temporal analyses of the disease progress in relation to this
criterion exhibited that the protection was quantitative, mainly reducing the TYLCV-Mld[RE] incidence by at maximum 50% at
low inoculation pressure. When graft inoculated, the final TYLCV-Mld[RE] disease incidence was 100% in both susceptible and
resistant genotypes with severe symptoms, suggesting a reduction of virus transmission by a vector resistance as a possible
mechanism. Implications of using such type of resistance in breeding programmes are discussed. 相似文献
24.
Serum concentration of S100-B protein in patients during CABG with or without cardiopulmonary bypass
AIM: To investigate the mutative law of the serum S100-B protein in patients undergone coronary artery bypass grafting with or without cardiopulmonary bypass (CPB-CABG or non-CPB CABG), and to compare the degree of cerebral injury in patients during CABG between the two different surgical manipulations.METHODS: 30 patients were divided into two groups: CPB-CABG group (group A) and non-CPB CABG group (group B). Every group included 15 patients. Blood from jugular vein was phlebotomized in every patients at the following 8 time points: before operation (OP), after anaesthesia, end of grafting, end of OP, 2 h after OP, 6 h after OP, 12 h after OP and 24 h after OP. The serum concentrations of S100-B protein in the samples were measured.RESULTS: The level of serum S100-B protein increased markedly at the beginning of CABG, and the peak value of group A (2.32 μg/L±0.26 μg/L) was treble higher than that in the patients in group B (0.71 μg/L±0.14 μg/L). The levels of S100-B protein tend to normal level in both groups 24 h after OP. The level of S100-B protein had notable relation with the time of CABG in group A and the manipulative time on the heart in group B.CONCLUSION: The degree of cerebral damage can be valued by investigating the mutative law of the serum S100-B protein in patients undergone CPB-CABG and non-CPB CABG. The non-CPB CABG reduces the degree of cerebral damage and avoids the functional disorder of central nerve. 相似文献
25.
剑麻纤维接枝丙烯酸吸水树脂的研究 总被引:3,自引:0,他引:3
以剑麻纤维为骨架,以一定中和度的丙烯酸和少量丙烯酰胺为单体,采用硫代硫酸钠(Na2S2O3)和过硫酸盐为引发体系,通过接枝反应制备纤维素基吸水树脂.考察引发体系及条件对制备吸水树脂的影响,探索单体配比、交联剂浓度对吸水树脂的吸水能力、吸水速率、保水性能和反复吸水性能的影响.结果表明:在硫代硫酸钠和过硫酸盐组成氧化还原引发体系中,采用过硫酸钾和过硫酸铵两种氧化剂组成的引发体系,在引发剑麻纤维接枝丙烯酸单体的反应中起到协同效应;有效地将过硫酸盐引发接枝反应的温度由常用的55~80℃降至30~50℃,同时,达到较高的接枝率和单体转化率.交联剂的用量、丙烯酰胺(AM)的用量和丙烯酸(AA)的用量对吸水倍率和吸盐水倍率有显著的影响.吸水树脂的最大吸水倍率为530 g/g,最大吸盐水倍率为58 g/g,吸水速率为8 g(g·min),树脂具有良好的保水性和热稳定性.FTIR分析结果表明,吸水树脂是纤维素和丙烯酸的接枝共聚物.TGA分析结果表明,吸水树脂比剑麻纤维热稳定性好. 相似文献
26.
27.
The literature on rootstock effects (on scions) in conifers was reviewed, specifically: graft success, compatibility, size, reproduction, phenology, crown and needle characters, mineral contents, organic compounds, water relations, disease resistance and wood properties. Scions usually had higher graft success and less incompatibility on more closely related rootstocks although there were exceptions. Even intergeneric grafts have succeeded on occasion. Although there were marked rootstock effects on growth and reproduction, the effects did not follow a pattern with increasing relationship. It is also likely that some crown characters and the nutrient content of scions can be manipulated by the use of rootstocks. For many characters, a specific rootstock may give a desired result only for a limited number of scion types (species, cultivars or clones). With some exceptions, the review shows that the subject has not been comprehensively studied. Many of the studies were either short-term, inadequately replicated, or poorly designed to allow firm conclusions about rootstock effects. The physiological and biochemical mechanisms, which cause the changes seen in morphology, are not well understood. Further research and more comprehensive study of rootstock effects on scion biology are recommended. 相似文献
28.
29.
通过换冠改良技术,板栗幼树生长很快,丰产稳产且性能很好。大部分植株第2年挂果,第3年便能丰产,且产量稳定,其经济效益是非常显著的。 相似文献
30.
杨树嫁接苗生长量与伐根直径及嫁接株数关系的研究 总被引:1,自引:0,他引:1
为了搞清杨树嫁接苗成活率和生长量与伐根直径及嫁接株数的关系 ,对杂交杨伐根嫁接冀秦 1号杨、冀秦 2号杨、冀秦 3号杨、山海关杨、加杨、 1- 2 14杨进行了研究。结果表明 :接穗品种虽不同但同属黑杨派 ,其嫁接在相同伐根上的成活率及胸径生长量均无显著差异 ;在本研究范围内 ,嫁接株数对嫁接苗的生长量产生显著的影响 ,而伐根直径及其交互作用对其影响不显著 ;伐根直径在 15~ 2 5cm时以嫁接 3株为宜 ,在 2 6~ 30cm时可嫁接 4株 相似文献