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471.
Summary. Following herbivory, induced responses involving plant secondary metabolites have been reported in a number of tree species.
Although a wide range of plant secondary metabolites appear to operate as constitutive plant defences in trees belonging to
the Eucalyptus genus, no induced responses have as yet been reported following foliar-chewing insect damage. We empirically tested whether
branch defoliation (artificial and larval) of 2-year-old Eucalyptus globulus Labill. trees altered the abundance of specific plant secondary metabolites immediately (3 months after initial larval feeding)
and 8 months after the cessation of larval feeding. Metabolites assayed, included essential oils, polyphenolic groups and
foliar wax compounds and in all cases their abundance was not significantly altered by defoliation. However, the level of
foliar tannins after 3 months of larval feeding did display a trend that suggested elevated levels as the result of defoliation,
though this trend was not evident 8 months later, indicating that, if real, the response was a rapid and not a delayed induced
response. The level of foliar tannins was also negatively correlated to both average larval survival and average percentage
branch defoliation, suggesting that foliar tannins may operate as toxins and/or anti-feedants to M. privata larval feeding. 相似文献
472.
W. Allen Hogge M.D. Carol Blank Linda B. Roochvarg Joan S. Hogge Eric A. Wulfsberg Leslie J. Raffel 《黑龙江环境通报》1994,14(8):725-727
The Gorlin (naevoid basal cell carcinoma) syndrome is an autosomal dominant disorder consisting principally of naevoid basal cell carcinomas, odontogenic keratocysts, skeletal abnormalities, and intracranial calcification. We report the prenatal detection of the Gorlin syndrome by ultrasonography in a fetus with macrocephaly and mild ventriculomegaly. 相似文献
473.
Eight patients were referred for prenatal diagnosis for suspected fetal cytomegalovirus infection (CMV): six for documented first-trimester infection and two for abnormal ultrasound evaluation suggestive of fetal infection. Three methods of diagnosis were employed: (1) amniotic fluid viral cultures and CMV-specific IgM in fetal serum; (2) amniotic fluid cultures and detection by polymerase chain reaction amplification of CMV-specific DNA in chorionic villi; and (3) detection of CMV-specific DNA in villus samples only. Amniotic fluid cultures detected all cases of infection, but CMV-specific IgM was not a reliable indicator of infection in any case. DNA analysis correlated well with both culture results and clinical outcome. 相似文献
474.
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476.
Accurate species identification is the cornerstone of any ecological study - yet this fundamental step is not always possible for marine zooplankton. Routine species' identification, especially of juvenile andlarval stages, is difficult for Calanus species (Copepoda; Calanoida) in the N. Atlantic Ocean, where two or three species may co-occur. A rapid, simple, and inexpensive molecularly based protocol to identify individual copepods of any life stage has beendeveloped. This protocol will routinely identify four Calanus species in the N. Atlantic and will help to accurately understand the role of each species in coastal and open ocean ecosystems. The DNA sequence of a 633 bp region of the mitochondrial cytochrome oxidase I (mtCOI) was determined for ten Calanus species: C. australis (Brodsky, 1959), C. chilensis (Brodsky, 1959), C. finmarchicus (Gunnerus, 1770), C. glacialis (Jaschnov, 1955), C. helgolandicus (Claus, 1863), C. hyperboreus (Krøyer, 1838), C. marshallae (Frost, 1974), C. pacificus (Brodsky, 1948), C. simillimus (Giesbrecht, 1902), and C. sinicus (Brodsky, 1965). MtCOI sequences were used to design species-specific oligonucleotide primers for C. finmarchicus, C. glacialis, C. helgolandicus, and C. hyperboreus and to optimize a competitive, multiplexed, species-specific PCR (SS-PCR) protocol to discriminate the four species. This corrects and improves a previously published protocol for three Calanus species (Bucklin et al. 1999: Hydrobiologia 401:239-254), unambiguously identifying individual copepods and copepodites from diverse geographic regions of the four species' ranges. In order to further examine the pattern of mtCOI evolution within Calanus (an important consideration for molecular systematic characters), consensus mtCOI sequences were used to reconstruct phylogenetic relationships among the ten species; the mtCOI gene tree agreed with morphological and molecular (based on mt16S rRNA) phylogenies, except that the affiliation of C. sinicus could not be resolved. 相似文献
477.
Robert Wallerstein Tracey Oh Judy Durcan Yaakov Abdelhak Mark Clachko Hana Aviv 《黑龙江环境通报》2002,22(8):722-724
We report the prenatal diagnosis of trisomy 6 mosaicism via amniocentesis, in which trisomy 6 cells were identified in three of five culture vessels with 33% (5/15) of colonies showing trisomic cells. The pregnancy was electively terminated and examination revealed minor abnormalities (shortening of the femurs, micrognathia, posterior malrotation of the ears, and bilateral camptomelia of the second digit of the hands and fifth digits of the feet). Cytogenetic analysis of the placenta showed trisomy 6 in 100% of 20 cells studied. Karyotype was 46,XX in 100 cells examined from fetal skin. There are relatively few prenatally diagnosed cases of mosaic trisomy 6 at amniocentesis. Confined placental mosaicism (CPM) has been postulated in other cases where follow-up cytogenetic studies were not available. The present case differs from those previously reported, as it appears to represent CPM of chromosome 6 with phenotypic effects to the fetus. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
478.
Potassium silicate drilling fluids(PSDF) are a waste product of the oil and gas industry with potential for use in land reclamation. Few studies have examined the influence of PSDF on abundance and composition of soil bacteria and fungi. Soils from three representative locations for PSDF application in Alberta, Canada, with clay loam, loam and sand textures were studied with applications of unused, used once and used twice PSDF. For all three soils, applying ≥ 40 m3/ha of used PSDF significantly affected the existing soil microbial flora. No microbiota was detected in unused PSDF without soil. Adding used PSDF to soil significantly increased total fungal and aerobic bacterial colony forming units in dilution plate counts, and anaerobic denitrifying bacteria numbers in serial growth experiments.Used PSDF altered bacterial and fungal colony forming unit ratios of all three soils. 相似文献
479.
Potassium silicate drilling fluids (PSDF) are a waste product of the oil and gas industry with potential for use in land reclamation. Few studies have examined the influence of PSDF on abundance and composition of soil bacteria and fungi. Soils from three representative locations for PSDF application in Alberta, Canada, with clay loam, loam and sand textures were studied with applications of unused, used once and used twice PSDF. For all three soils, applying ≥40 m3/ha of used PSDF significantly affected the existing soil microbial flora. No microbiota was detected in unused PSDF without soil. Adding used PSDF to soil significantly increased total fungal and aerobic bacterial colony forming units in dilution plate counts, and anaerobic denitrifying bacteria numbers in serial growth experiments. Used PSDF altered bacterial and fungal colony forming unit ratios of all three soils. 相似文献
480.
Allen S. Heagle John W. Johnston 《Journal of the Air & Waste Management Association (1995)》2013,63(7):729-732
Foliar injury and shoot fresh weight responses of soybeans (Glycine max L.) ‘Lee 68’ and ‘Dare’ exposed to mixtures of ozone (O3) and sulfur dioxide (SO2) were greater than additive (synergistic), less than additive (antagonistic), or additive. The result depended on the concentrations of O3 and SO2, the exposure duration, and the amount of injury caused by each gas singly. Synergism usually occurred when injury from O3 or SO2 singly was slight to moderate. Antagonism usually occurred when injury from either gas singly was severe. In many cases of antagonism, the injury and fresh weight effects of the mixture were less than those from SO2 alone, suggesting that O3 can sometimes protect soybeans from SO2. 相似文献