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71.
Fatty-acid-binding protein (FABP) from the flight muscle of the locust, Schistocerca gregaria, is similar to mammalian heart FABP in its primary structure and biochemical characteristics. We have studied developmental changes using enzyme-linked immunosorbent assays, RNA hybridization and electron microscopy of immunogold-labeled sections. Locust muscle FABP is the most abundant soluble muscle protein in fully developed adult locusts, comprising 18% of the total cytosolic protein. At the beginning of the adult stage, however, no FABP is detectable. Its concentration rises during the following 10 days, after which it reaches its maximal value. FABP mRNA is present shortly after adult ecdysis; its concentration increases for 10 days, before it diminishes and reaches a constant, low level, probably needed to maintain the established FABP level. The protein is abundant in cytosol and nuclei, but virtually absent in mitochondria.  相似文献   
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Pattern recognition has been used in this paper to analyze trace element levels in patients diagnosed with nasal-pharynx cancer (NPC) and in healthy control subjects. Trace elements such as Zn, Cu, Fe, Mn, and Mg have been tested in samples of hair and whole blood. Through Mahalanobis Distance Decision analysis, we have achieved good classification effects in whole blood samples: Efficiency for distinguishing patients is 96% and that of healthy controls is 90%. Classification hair samples is inferior to whole blood: Decision accuracy for patients is 58% and healthy controls is 90%. These results are also shown in a nonlinear mapping figure. At the same time, we have also determined 5 trace element levels in 16 other cancer patients' nonneoplastic and cancerous tissue, with no significant difference between them: Decision accuracy of cancerous tissue is 63%, and in nonneoplastic tissue is 50%, hence, we cannot identify them. It can be inferred that there is no idiosyncratic change of trace elements in cancer patients' neoplastic tissue, the change of a cancerous person may occur in the whole body.  相似文献   
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Leaf mass per unit area (LMA), carbon and nitrogen contents, leaf construction cost, and photosynthetic capacity (P max) of Adiantum reniforme var. sinensis, an endangered fern endemic to the Three Gorges region in southwest China, were compared in five populations differing in habitat such as soil moisture and irradiance. The low soil moisture and high irradiance habitat population exhibited significantly higher LMA, area-based leaf construction (CCA), and carbon content (CA), but lower leaf nitrogen content per unit dry mass (NM) than the other habitat populations. The high soil moisture and low irradiance habitat populations had the lowest CCA, but their cost/benefic ratios of CCA/P max were similar to the medium soil moisture and irradiance habitat population due to their lower leaf P max. Hence A. reniforme var. sinensis prefers partially shaded, moist but well-drained, slope habitats. Due to human activities, however, its main habitats now are cliffs or steeply sloped bare rocks with poor and thin soil. The relatively high energy requirements and low photosynthetic capacity in these habitats could limit the capability of the species in extending population or interspecific competition and hence increase its endangerment.  相似文献   
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Recent molecular studies of symbiotic dinoflagellates (genus Symbiodinium) from a wide array of invertebrate hosts have revealed exceptional fine-scale symbiont diversity whose distribution among hosts, regions and environments exhibits significant biogeographic, ecological and evolutionary patterns. Here, similar molecular approaches using the internal transcribed spacer-2 (ITS-2) region were applied to investigate cryptic diversity in Symbiodinium inhabiting soritid foraminifera. Approximately 1,000 soritid specimens were collected and examined during a 12-month period over a 40 m depth gradient from a single reef in Guam, Micronesia. Out of 61 ITS-2 types distinguished, 46 were novel. Most types found are specific for soritid hosts, except for three types (C1, C15 and C19) that are common in metazoan hosts. The distribution of these symbionts was compared with the phylotype of their foraminiferal hosts, based on soritid small subunit ribosomal DNA sequences, and three new phylotypes of soritid hosts were identified based on these sequences. Phylogenetic analyses of 645 host-symbiont pairings revealed that most Symbiodinium types associated specifically with a particular foraminiferal host genus or species, and that the genetic diversity of these symbiont types was positively correlated with the genetic diversity found within each of the three host genera. Compared to previous molecular studies of Symbiodinium from other locations worldwide, the diversity reported here is exceptional and suggests that Micronesian coral reefs are home to a remarkably large Symbiodinium assemblage.  相似文献   
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A low copy number cosmid   总被引:8,自引:1,他引:7  
A low copy number cosmid was constructed by subcloning the pair of cos sites and the kanamycin resistance gene of pcos2EMBL into pGB2. The resulting cosmid, pPR691, has the pSC101 replicon and specifies resistance to kanamycin, spectinomycin, and streptomycin. pPR691 also carries restriction sites suitable for cloning partial Sau3A digests using the strategy of Bates and Swift (P. F. Bates and R. A. Swift, 1983, Gene 26, 137-146). A library of Salmonella typhimurium chromosomal DNA was made using this cosmid and the rfb gene cluster (map position 42) was isolated from this library.  相似文献   
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Changes in growth, physiological and biochemical characteristics under salt stress with or without La3+ treatment in Saussurea involucrata Kar. et Kir. were investigated. The results showed that La3+ relieved the plant growth inhibition, improved the leaf water potential and water content, increased the soluble protein and the proline contents and decreased malondialdehyde content under salt stress. Further, addition of La3+ significantly increased the activities of superoxide dismutase, ascorbate peroxidase, catalase, and glutathione reductase, decreased the photosynthetic pigment decomposition and increased the ratio of total chlorophyll to carotenoids under salt stress.  相似文献   
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