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171.
Targeted radiotherapy with 211At-methylene blue (211At-MTB) is a systemic treatment selectively directed at melanoma due to a high affinity of MTB to melanin synthesized in the tumor cells. Since MTB forms a strong complex with melanin, it is an effective carrier for a number of radioisotopes to be addressed to the tumor deposits of any size including individually dispersed melanoma cells. Thus, appropriately radiolabeled MTB can be used for either diagnosis or therapy of the neoplasm. As predicted and found in animal experiments, 211At-MTB is most effective therapeutically. Histopathological investigations showed that the highly pigmented 211At-MTB-treated tumors were characterized initially by perivascular oedema and hydropic degeneration of tumor cells followed by gradual development of extensive areas of coagulative necrosis. The necrotic tumor areas contained microvessels occluded by thrombi and tended to undergo microfocal calcification. Although melanoma-bearing animals successfully treated with 211At-MTB did not reveal any adverse effects of the therapy, detailed toxicological studies were undertaken. No serious macro- or microscopic lesions were observed in normal organs of 211At-MTB treated mice. Only the relative number of small lymphocytes in the groin lymph nodes in a minority of animals was variably reduced, most often in conjunction with the treatment of highly, but not poorly, pigmented tumors. 相似文献
172.
ADAM PORTER 《Ecological Entomology》1997,22(2):189-196
1. The butterflies Pieris napi and Pieris bryoniae hybridize in a narrow zone at ≈ 1200 m in the Alps and Carpathians of Europe. They feed as larvae on a variety of hosts in the Brassicaceae, and few host species occur on both sides of the hybrid zone.
2. Females were captured on either side of the hybrid zone at Pont de Nant, Switzerland, eggs obtained, and larvae were offered plants from nineteen species of Brassicaceae and Reseda lutea (Resedaceae).
3. Nine of the hosts were found to have eggs or larvae already on them. Only Capsella bursa-pastoris and R. lutea were unsuitable.
4. Significant survivorship differences among suitable hosts were found. There was no interaction between butterfly species and host plant, which would indicate adaptation by these taxa to their respective suites of hosts.
5. Among suitable hosts, larvae of both taxa had higher mortality on plants with hairy leaves and on older plants beginning to senesce.
6. Differential selection on host use, if it occurs at all, is likely to be a very minor factor in the dynamics of the Pieris napi / bryoniae hybrid zone. 相似文献
2. Females were captured on either side of the hybrid zone at Pont de Nant, Switzerland, eggs obtained, and larvae were offered plants from nineteen species of Brassicaceae and Reseda lutea (Resedaceae).
3. Nine of the hosts were found to have eggs or larvae already on them. Only Capsella bursa-pastoris and R. lutea were unsuitable.
4. Significant survivorship differences among suitable hosts were found. There was no interaction between butterfly species and host plant, which would indicate adaptation by these taxa to their respective suites of hosts.
5. Among suitable hosts, larvae of both taxa had higher mortality on plants with hairy leaves and on older plants beginning to senesce.
6. Differential selection on host use, if it occurs at all, is likely to be a very minor factor in the dynamics of the Pieris napi / bryoniae hybrid zone. 相似文献
173.
The growth of three species of mussels in the White Nile nearKhartoum was studied from caged specimens and natural populations.True annual rings develop as a result of a silting-induced restingstate during the annual flood from July to October. False ringsalso develop, possibly as a result of unfavourable factors likethe change of habitat, inadequate food, handling of the mussels. Growth is inhibited during November-January as a result of thelower water temperature and reproduction. However, there wasevidence that during this period juveniles grew at a higherrate than the adults. It could be concluded that there is atrade-off between reproductive effort and growth in the adults;growth is inhabited until the eggs are released from the gonadsinto the demibranchs. The period from February to July is the growth season; it ischaracterised by high water temperature and high transparency.The mussels had already spawned by February. Significant incrementswere observed on the shells of caged specimens especially afterMay. These increments were, however, smaller than comparablegrowth in natural populations. This indicated that the cageshad suppressed the growth of the mussels. Growth rates are slow. Estimation of maximum sizes for the unionidsusing Ford-Walford plots was almost in full agreement with theactual maximum sizes. The poor agreement in the case of M. dubiais related to the fact that this species is not well establishedin the habitat.
1Present Address: Biology Department, Royal Holloway and BedfordNew College, Egham, Surrey TW20 0EX (Received 4 April 1989; accepted 20 July 1989) 相似文献
174.
Machaerotidae (Hemiptera: Auchenorrhyncha: Cercopoidea) is a taxonomically small but morphologically diverse family of spittlebugs with approximately 115 described species in 31 genera and an exclusively Palaeotropical distribution. Results are presented of the first molecular phylogenetic investigation of Machaerotidae, examining relationships among the currently recognized subfamilies and tribes, as well as determining the phylogenetic placement of the genera Enderleinia Schmidt, Neuromachaerota Schmidt, Labramachaerota Bell & Cryan, and Kyphomachaerota Bell & Cryan. DNA nucleotide sequence data from eight loci (12s rDNA, 16s rDNA, 18S rDNA, 28S rDNA, histone 2A, histone 3, wingless and NADH Dehydrogenase subunit 4) were analysed to reconstruct the phylogeny. The evidence generated in this study supports the following systematic conclusions: (i) Machaerotidae is a monophyletic family; (ii) Machaerotini, Hindoloidini (with the new inclusion of Kyphomachaerota), and Enderleiniini (excluding Kyphomachaerota and Apomachaerota Schmidt) are monophyletic tribes; (iii) the genus Apomachaerota was recovered as the most anciently diverged lineage of extant Machaerotidae, and a new subfamily (Apomachaerotinae subfam.n. ), is proposed on the basis of its phylogenetic placement as sister lineage to all other extant Machaerotidae. 相似文献
175.
176.
ERIC A. HOFFMAN J. ROMAN ARGUELLO NICLAS KOLM ANDERS BERGLUND ADAM G. JONES 《Molecular ecology resources》2004,4(3):342-344
We describe the isolation and characterization of 11 polymorphic tetranucleotide microsatellite loci from a male mouthbrooding coral reef fish, the Banggai cardinalfish Pterapogon kauderni. In a sample of 37 fish from a natural population, polymorphism at these loci ranged from two to 15 alleles, with expected heterozygosities ranging from 0.107 to 0.928, enabling high‐resolution genetic studies of this coral reef fish. 相似文献
177.
ADAM D. MORRIS DARREN A. MILLER MATINA C. KALCOUNIS-RUEPPELL 《The Journal of wildlife management》2010,74(1):26-34
ABSTRACT Forest edges often have increased species richness and abundance (edge effect) and affect spatial behaviors of species and dynamics of species interactions. Landscapes of intensively managed pine (Pinus spp.) stands are characterized by a mosaic of patches and linear forest edges. Managed pine forests are a primary landscape feature of the southeastern United States, but the effects of intensive management on bat communities are poorly understood. Insectivorous bats are important top predators in nocturnal forest food webs. We examined bat foraging behavior along forest edges and in 4 structurally distinct stand types (open-canopy pine, prethinned pine, thinned pine, and unmanaged forest) within a managed pine forest in the coastal plain of North Carolina, USA. During May-August, 2006 and 2007, we recorded echolocation calls using Pettersson D240X bat detectors linked to digital recorders at 156 sites. We also sampled nocturnal flying insects at each site using Malaise insect traps. We used negative binomial count regression models to describe bat foraging behavior relative to forest edges, stand types, and prey availability. Although some species showed affinities for certain stand types and prey items, bat activity patterns were most strongly related to forest edges. Edges were used extensively by 6 aerial-hunting bat species, but avoided by Myotis species. Forest edges function similarly to natural forest gaps, by providing foraging opportunities for aerial-hunting bat species. Therefore, the maintenance of forest edges in managed pine landscapes may enhance foraging habitat for aerial-hunting bat species. 相似文献
178.
MOHAMED HASSAN BENAJIBA ADAM MARQUES JIÍ LOM GEORGES BOUIX 《The Journal of eukaryotic microbiology》1994,41(3):215-222
ABSTRACT. Ultrastructural studies on Eimeria (syn. Epieimeria ) anguillae (Apicomplexa), parasite of the digestive tract of the eel, have shown that the development of this parasite takes place completely within the host cell. Merogony and gamogony are intracellular but in the epicytoplasmic position. Sporogony is also located within the epithelial cells, which agrees with assignment of this coccidian in the family Eimeriidae. However, depending on the intensity of infection and the physiopathological reaction of the host, the gamont may behave in two ways. 1) In massive infections, gamogony stages cause a genuine destruction of intestinal epithelium. Large numbers of gamonts form nodules and parts of the seriously destroyed epithelium peel off and are released into the lumen of the gut and quickly discharged into the outer environment. This discharged epithelium envelops cells containing immature oocysts that then sporulate outside the host. 2) In light infections, the host cells, which are necrotic due to the presence of a zygote, are pushed between the surrounding intact cells towards the base of the epithelium. Closely above its basal lamella, the oocyst then undergoes sporulation. These results show no taxonomically important biological features (e.g. special mode of implantation to the host cell or active movement of the zygote). Because the morphological characteristics of Epieimeria do not differ significantly from Eimeria , we propose to suppress the genus Epieimeria Dyková and Lom, 1981, and relegate its species into the genus Eimeria . 相似文献
179.
180.
ADAM LANGE KARIN GILLER OLAF PONGS STEFAN BECKER MARC BALDUS 《Journal of receptor and signal transduction research》2013,33(5-6):379-393
Solid-state NMR (ssNMR) represents a spectroscopic method to study membrane protein structure and dynamics in lipid bilayers. We present two-dimensional correlation experiments conducted on a fully [13C,15N] labeled version of a chimeric potassium (KcsA-Kv1.3) channel. Data obtained by using two different ion concentrations suggest a structural conservation of the selectivity filter region. SsNMR experiments conducted at two different temperatures point to differential molecular dynamics of the channel. 相似文献