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101.
Proteome analysis has rapidly developed in the post-genome era and is now widely accepted as the complementary technology for genetic profiling. It has been shown to be a powerful tool for studying human diseases and for identifying novel prognostic, diagnostic and therapeutic markers. This review focuses on the identification of new biomarkers and therapeutic targets for renal cell carcinoma using different 'ome'-based technologies.  相似文献   
102.
Microsatellite DNA markers were used to investigate parentage relationships in a population of common cuckoo Cuculus canorus . Thirty adults and 55 nestlings were genotyped at six loci from blood samples collected over a four-year period. To test whether each cuckoo female specialises in parasitising one single host species (Host Preference Hypothesis), the maternal relationships were used to record each female's host choice. The results supported the Host Preference Hypothesis since no female (N=3) was recorded to have parasitised more than one of four congeneric host species breeding in the area. In contrast, the males (N=4) did not show such specialisation since two of them sired offspring reared by different host species.  相似文献   
103.
Free-living nematodes are known to ingest food-borne pathogens and may serve as vectors to contaminate preharvest fruits and vegetables. Caenorhabditis elegans was selected as a model to study the effectiveness of sanitizers in killing Salmonella enterica serotype Poona ingested by free-living nematodes. Aqueous suspensions of adult worms that had fed on S. enterica serotype Poona were treated with produce sanitizers. Treatment with 20 μg of free chlorine/ml significantly (α = 0.05) reduced the population of S. enterica serotype Poona compared to results for treating worms with water (control). However, there was no significant difference in the number of S. enterica serotype Poona cells surviving treatments with 20 to 500 μg of chlorine/ml, suggesting that reductions caused by treatment with 20 μg of chlorine/ml resulted from inactivation of S. enterica serotype Poona on the surface of C. elegans but not cells protected by the worm cuticle after ingestion. Treatment with Sanova (850 or 1,200 μg/ml), an acidified sodium chlorite sanitizer, caused reductions of 5.74 and 6.34 log10 CFU/worm, respectively, compared to reductions from treating worms with water. Treatment with 20 or 40 μg of Tsunami 200/ml, a peroxyacetic acid-based sanitizer, resulted in reductions of 4.83 and 5.34 log10 CFU/worm, respectively, compared to numbers detected on or in worms treated with water. Among the organic acids evaluated at a concentration of 2%, acetic acid was the least effective in killing S. enterica serotype Poona and lactic acid was the most effective. Treatment with up to 500 μg of chlorine/ml, 1% hydrogen peroxide, 2,550 μg of Sanova/ml, 40 μg of Tsunami 200/ml, or 2% acetic, citric, or lactic acid had no effect on the viability or reproductive behavior of C. elegans. Treatments were also applied to cantaloupe rind and lettuce inoculated with S. enterica serotype Poona or C. elegans that had ingested S. enterica serotype Poona. Protection of ingested S. enterica serotype Poona against sanitizers applied to cantaloupe was not evident; however, ingestion afforded protection of the pathogen on lettuce. These results indicate that S. enterica serotype Poona ingested by C. elegans may be protected against treatment with chlorine and other sanitizers, although the basis for this protection remains unclear.  相似文献   
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106.
The effects of severe thermal stress imposed by the intermittentoperation of a nuclear reactor on plankton abundance and dynamicswere investigated in Pond C, a cooling reservoir on the SavannahRiver Site in South Carolina, USA. Temperatures in Pond C rangedup to 58°C during reactor operation. The thermal effluenteliminated zooplankton from regions where the temperature exceeded45°C, reduced zooplankton abundance by 1–3 ordersof magnitude and typically halved the number of taxa. Reactoroperation also reduced phytoplankton biovolume, often by >70%.During intermittent reactor operation, the rotifer Filinia longisetadominated the zooplankton and two cladocerans of the genus Moinawere abundant. These species were not abundant during extendedreactor shutdowns. The success of Filinia and Moina was dueprimarily to their tolerance of high temperatures. Sparse phytoplanktonprobably limited some zooplankton taxa, although other taxa,such as Filinia may have utilized bacterial resources. Reactoroperation may have intensified predation on crustacean zooplanktonwhen fish were concentrated in refuge areas with zooplankton.Processes by which zooplankton repopulated the reservoir afterreactor shutdown were inferred from zooplankton distributionpatterns, and population growth and birth rates. Repopulationtypically occurred within a few days due to rapid growth ofpopulations from refuge areas within the reservoir and colonistsbrought in through a tributary canal. Mechanisms of zooplanktonrepopulation in Pond C suggest that refuges or colonizationcorridors should be maintained when the re-establishment ofcommunities following cessation of stresses is desired.  相似文献   
107.
Barbara C. Boyer 《Hydrobiologia》1995,305(1-3):217-222
In spiralian embryos determination of the axes of bilateral symmetry is associated with D quadrant specification. This can occur late through equal cleavage and cell interactions (conditional specification) or by the four-cell stage through unequal cleavage and cytoplasmic localization (autonomous specification). Freeman & Lundelius (1992) suggest that in spiralian coelomates the former method is ancestral and the latter derived, with evolutionary pressure to shorten metamorphosis resulting in early D quadrant determination through unequal cleavage and appearance of adult features in the larvae. Because of the key phylogenetic position of the turbellarian platyhelminthes, understanding the method of axis specification in this group is important in evaluating the hypothesis. Polyclad development, with equal quartet spiral cleavage, is believed to represent the most primitive condition among living turbellarians and has been examined experimentally in Hoploplana inquilina. Blastomere deletions at the two and four-cell stage produce larvae that are abnormal in morphology and symmetry, indicating that early development is not regulative, and also establish that the embryo does not have an invariant cell lineage. Deletions of micromeres and macromeres at the eight-cell stage indicate that cell interactions are involved in dorso-ventral axis determination, with cross-furrow macromeres playing a more significant role than non-cross-furrow cells. The results support the idea that conditional specification is the primitive developmental mode that characterized the common ancestor of the turbellarians and spiralian coelomates. Evolutionary trends in development in polyclads and other turbellarian orders are discussed.  相似文献   
108.
New distributional recores of hydroxycinnamoyl spermidines (HCS), including novel trisubstituted HCSs and flavonol glycosides, in pollen of Higher Hamamelidae are presented. The 51 taxa analyzed by HPLC and TLC included members of the families Fagaceae (Castanoideae, Fagoideae, Quercoideae), Betulaceae, Juglandaceae, Myricaceae, Hamamelidaceae, Rosaceae, and Buxaceae (Simmondsia). The results support generic concepts in the Higher Hamamelidae derived from morphological and chloroplast DNA data and support a close evolutionary relationship between the Higher Hamamelidae and the Rosidae.  相似文献   
109.
Two six-week laboratory experiments were conducted to evaluate effects of pesticides and microcosm size on benthic estuarine macroinvertebrate recolonization. Sediments fortified with the pesticides (fenvalerate: controls, 5 (low) and 50 μg g−1 wet sediment (high); endosulfan: controls, 1 (low) and 10 μg g−1 wet sediment (high)) were fine-grained, organically rich (approximately 3.5% organic carbon and 22% dry weight) material. Relative dominance of the four most abundant taxa in both experiments was consistent among treatments with few exceptions. The amphipod,Corophium acherusicum, dominated abundance in both experiments. In the fenvalerate experiment, large trays (400 cm2) contained significantly (p<0.05) more total number of taxa (TNT) than small microcosms (144 cm2) but tray size was not significantly related to total number of organisms (TNO). When size was adjusted to a common unit area, small trays contained significantly more TNO than large containers. Adjusted abundance of small trays was 2.5 times that of large containers; a ratio close to that of microcosm sizes (i.e., 2.8). This result suggests that larval supply may have been inadequate to ‘aturate’ the available sediment in large containers. Fenvalerate significantly reduced abundance in the high treatment compared to both controls and low treatment but low treatment was not significantly different from controls. The amphipod,Corophium acherusicum, accounted for most of the decrease in abundance in response to fenvalerate. The holothruroid,Leptosynpta sp. and the polychaete,Mediomastus ambiseta, increased in abundance significantly with increased concentration of fenvalerate. Combined effects of actual microcosm size and concentration of endosulfan were not significant for TNO or TNT. As in the fenvalerate experiment, adjusted abundance of small microcosms was 2.6 times that of large trays which approximated the ratio of unit area between microcosm sizes. Abundance of a few taxa responded significantly to adjusted and unadjusted unit area. Abundance of the tunicate,Molgula manhattensis, increased significantly with increased concentration of endosulfan. Abundance was affected by sample location (e.g., interiorvs exterior cores) within microcosms. Abundance adjusted to unit area resulted in significantly greater TNO in externalvs internal cores. This has importance for sequential sub-sampling of microcosms to determine temporal dynamics. Statistically significant effects were measured in benthic community structure associated with microcosm size; however, the magnitude was relatively small. There appears to be no major biological reason to select one microcosm size over the other for screening for contaminant effects. Where feasible, the small trays provide savings in sample preparation and analysis, allow more replicates where laboratory space is limiting and generate less chemical waste. These benefits may be off-set by less ‘artifacts’ associated with edge effects of larger microcosms and the need for a larger mass of sediment to accommodate additional analytical requirements (e.g., thin vertical surficial samples to refine contaminant exposure at the sediment/water interface).  相似文献   
110.
    
Zusammenfassung Im Frühjahr 1995 (Febr.–Mai) wurden auf der Schwäbischen Alb 7 Kolkrabenpaare beobachtet. Ziel der Untersuchung war es den Aufwand der Altvögel für die Jungenaufzucht zu erfassen. Der Aufwand wurde über die Aktivität der Altvögel am Nest abgeschätzt und bezüglich der Jungenzahl und des Wetters ausgewertet. Paare, die mehrere Junge hatten, sparten beim Hudern Kosten ein, da sie ihre Jungen bis zu einem geringeren Alter hudern mußten und weniger stark von der Temperatur abhängig waren. Bei den Fütterungen verringerte sich die Fütterfrequenz pro Jungvogel mit zunehmender Jungenzahl, die absolute Anzahl an Fütterungen nahm jedoch zu. Der Aufwand für die Nesthygiene war unabhängig von der Jungenzahl. Selbst bei mehreren Jungen blieb Zeit für Komfortverhalten. Jungenaufzucht war also effektiver, wenn mehrere Jungen gleichzeitig aufgezogen wurden.
Parental expenditure for rearing nestlings by ravensCorvus corax
In spring 1995 (Feb.–May) I observed seven pairs of Raven in southern Germany on the Schwäbischen Alb. The aim was to record parental expenditure for rearing nestlings. Expenditure was assessed by recording the activities of the adults at their nest (mainly brooding and feeding the offspring) and was analysed with respect to the number of nestlings per brood and with respect to the weather. Pairs with more than one nestling saved effort by stopping brooding their offspring at a lower nestling age. Also brooding was less dependent on the ambient temperature for pairs with more than one nestling than for pairs with only one nestling. The feeding frequency per nestling has been lower, if there were more nestlings to feed. The total frequency of feeding increased with increasing number of nestlings per brood. The effort for the hygiene of the nest was independent upon the number of offspring per nest. Nevertheless, pairs with more than one nestling spent time for comfort behaviour. Thus, it was more effective to reare more than one nestling at a time.
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