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11.
Four species of the family Polycentropodidae –Plectrocnemia baculifera, P. kusnezovi, Paranyctiophylax hjangsanchonus and Polyplectropunocturnus– are recorded from Korea. Polyplectropus nocturnus is newly recorded from the Korean peninsula. The other three species are recorded from the Republic of Korea for the first time.  相似文献   
12.
This study explored consumer liking and perception of pork patties with an added functional health ingredient: shiitake (Lentinus edodes P.) mushroom powder. In addition, patties with and without sodium tripolyphosphate were tested. Both native Korean and U.S. consumers evaluated the products. Pork patties made with both phosphate and mushroom powder were found to be acceptable by Korean consumers, but increases in mushroom powder in patties with phosphate decreased acceptability for U.S. consumers. However, addition of mushroom powder to patties without phosphate increased acceptability for U.S. consumers, perhaps because it tended to increase texture acceptance and juiciness. Thus, addition of mushroom powder as a functional ingredient in pork patties, while possible, would require different formula modifications to appeal to consumers of differing nationalities.  相似文献   
13.
Controversies regarding the function of guard cell chloroplasts and the contribution of mesophyll in stomatal movements have persisted for several decades. Here, by comparing the stomatal opening of guard cells with (crl‐ch) or without chloroplasts (crl‐no ch) in one epidermis of crl (crumpled leaf) mutant in Arabidopsis, we showed that stomatal apertures of crl‐no ch were approximately 65–70% those of crl‐ch and approximately 50–60% those of wild type. The weakened stomatal opening in crl‐no ch could be partially restored by imposing lower extracellular pH. Correspondingly, the external pH changes and K+ accumulations following fusicoccin (FC) treatment were greatly reduced in the guard cells of crl‐no ch compared with crl‐ch and wild type. Determination of the relative ATP levels in individual cells showed that crl‐no ch guard cells contained considerably lower levels of ATP than did crl‐ch and wild type after 2 h of white light illumination. In addition, guard cell ATP levels were lower in the epidermis than in leaves, which is consistent with the observed weaker stomatal opening response to white light in the epidermis than in leaves. These results provide evidence that both guard cell chloroplasts and mesophyll contribute to the ATP source for H+ extrusion by guard cells.  相似文献   
14.
为了解重庆三峡库区柑橘叶片硼营养状况及其影响因子,在该区域12个主产县(区)的代表性果园采集叶片样品954份和土壤样品302份,测定叶片硼含量,并分析了土壤有效硼、土壤pH值、品种、砧木和树龄对叶片硼营养的影响.结果表明: 该区域柑橘叶片硼含量不足(<35 mg·kg-1)的果园比例达41.6%,土壤有效硼含量不足(<0.5 mg·kg-1)的果园比例高达89.4%,柑橘叶片硼含量与土壤有效硼含量的相关性未达显著水平.土壤pH值、品种、砧木和树龄均影响叶片硼含量.pH值4.5~6.4土壤上的柑橘叶片硼含量显著高于pH值6.5~8.5土壤上的柑橘;品种间叶片硼含量为:温州蜜柑>柚类>夏橙>普通甜橙>杂柑>脐橙;枳砧和酸柚砧柑橘叶片硼含量显著高于枳橙砧和红橘砧柑橘;3~8年生柑橘树叶片硼含量适宜(35~100 mg·kg-1)样品比例比8年生以上柑橘树高6.6%.  相似文献   
15.
将感染质型多角体病毒的松毛虫中肠分为四种类型 ,研究各型所占比例与病毒产量间的关系 ,结果显示单位虫重的病毒产量随Ⅰ、Ⅱ类比例的增大而增高 ,Ⅰ、Ⅱ类比例为 2 1% - 80 %时 ,每公斤虫的病毒产量为 5.59× 10 10 PIB - 55.2 1× 10 10 PIB ,适宜的采收时机为Ⅰ、Ⅱ类比例为 60 % -80 %时 ,此时采收 ,每公斤虫可产出质型多角体病毒 37.2 1× 10 10 PIB~ 55.2 1× 10 10 PIB  相似文献   
16.
Chironomidae is usually the most abundant macroinvetebrate in freshwater. They form an important part of the foodweb, and also have long been known as indicators of water quality. However, there is a great deal of difficulty in its identification. Such is due to the complexity of larval taxonomy. The external fine structures of the mouth parts and antennae of 4th instar larva C. flaviplumus and C. salinarius were examined using scanning electron microscopy (SEM). The antennae of the fourth instar larvae of C. flaviplumus and C. salinarius are short and composed of five segments. They consist of a scape, pedical, and three flagellar subsegments. The maxilla palps have 10 sensilla basiconica on its distal surface. They show the three morphological groups in the following numbers: six apical sensillae, three medial sensillae, and one lateral sensillae. The mandibles have strong apical and lateral teeth. These sensory structures are situated on the head capsule, each of which are represented with images to elucidate the identification of chironomidae.  相似文献   
17.
Abstract.  1. Dispersal flight, a well-known strategy for aphids to locate suitable plants, was studied for its possible role in disseminating fungal pathogens and parasitoids as natural control agents of aphids by air captures in Hangzhou, China during 2001–2005. Up to 3183 migratory alates of green peach aphid Myzus persicae were captured from air using a yellow-plus-plant trap on the top platform of a six-storey building in an urbanised area, and individually reared in a laboratory for ≥ 7 days.
2. Among the captured alates, 28.9% survived on average for 2.5 days and then died from mycoses attributed to 10 species of obligate or non-obligate aphid pathogens. These were predominated by Pandora neoaphidis , which was causative of 80% of the mycosed alates. Another 4.4% survived for an average of 3.7 days, followed by mummification of Aphidius gifuensis (52.9%) and Diaeretella rapae (47.1%).
3. Numerous progeny colonies individually initiated by infected, parasitised, or healthy alates were monitored daily for 12 days, and fitted well to a logistic equation depicting the potential of their post-flight colonisation and fecundity. Both infected and parasitised alates from air were highly capable of initiating progeny colonies independently, although their potential fecundity was greatly reduced compared with that of healthy counterparts.
4. Our results confirmed that both obligate and non-obligate pathogens can be widespread with aphid dispersal flight, and demonstrated that parasitoids also took advantage of the host flight for their dispersal. This study provides new insights into aphid dispersal biology.  相似文献   
18.
We describe in detail the floral ontogeny of Nymphaea tetragona from a wild population to provide evidence regarding the phylogenetic position of Nymphaea and to reveal evolutionary trends of flowers in Nymphaeaceae by comparison with that of the other genera. Four sepals are initiated unidirectionally. The basal petals are initiated unidirectionally and alternate with the sepals. The dome‐shaped floral apex continues to expand and produces more petal and stamen primordia. The remaining petals and all stamens are initiated in spirals or whorls. Later, the periphery of the floral apex grows more quickly than the centre and results in a depression in the centre of the apex after all stamens have been initiated. Carpels are simultaneously initiated in a cycle at the periphery of the depression. They are ascidiate. After all organs have been initiated, the centre of the depression on the floral apex grows and develops into a globular structure. The connected inferior ovary, stigma caps and the globular floral apex together form an extragynoecial compitum. Within Nymphaeaceae, the floral ontogeny of Nymphaea is most similar to that of Euryale and Victoria. It differs more from Ondinea and Barclaya, and differs most from Nuphar. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 211–221.  相似文献   
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20.
目的:探讨超声引导下肝动脉栓塞化疗治疗进展期大肝癌的疗效和临床应用价值.方法:对我院2009年收治的60例原发性肝癌晚期患者进行超声引导下肝动脉栓塞化疗治疗.并通过彩色多普勒复查肿瘤的血供情况.结果:60例晚期肝癌患者在经过治疗后肝功能有了明显的改善,肿瘤内部及周边血流明显减少,肿瘤血供≥Ⅱ级者由TACE治疗前的90%(54/60)降为术后的71.67%(43/60).结论:在超声引导下准确定位,经肝动脉化疗是晚期肝癌的有效治疗手段,具有较高的安全性和依从性.  相似文献   
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