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991.
992.
Search for indicators of neurodegenerative disorders is a hot topic where much research remains to be done. Our aim was to determine proton nuclear magnetic resonance (1H-NMR) spectra of brain metabolites in the trimethyltin (TMT) model of neurodegeneration. Male Wistar rats were subjected to TMT or saline and were sacrificed on day 3 or 24 after administration. 1H-NMR spectrum was measured on the 600 MHz Varian VNMRS spectrometer in nano-probe in the volume of 40 μl of hippocampal extracts. TMT administration resulted in reduction of the hippocampal weight on day 24. Of the sixteen identified metabolite spectra, decreased aspartate and increased glutamine contents were observed in the initial asymptomatic stage of neurodegeneration on day 3 in hippocampal extracts of TMT exposed rats compared to sham animals. Increased myo-inositol content was observed on day 24. The presented data provide further knowledge about this experimental model and putative indicators of neuronal damage.  相似文献   
993.
994.
995.
Brood parasitic birds, their foster species and their ectoparasites form a complex coevolving system composed of three hierarchical levels. However, effects of hosts’ brood parasitic life‐style on the evolution of their louse (Phthiraptera: Amblycera, Ischnocera) lineages have never been tested. We present two phylogenetic analyses of ectoparasite richness of brood parasitic clades. Our hypothesis was that brood parasitic life‐style affects louse richness negatively across all avian clades due to the lack of vertical transmission routes. Then, narrowing our scope to brood parasitic cuckoos, we explored macroevolutionary factors responsible for the variability of their louse richness. Our results show that taxonomic richness of lice is lower on brood parasitic clades than on their nonparasitic sister clades. However, we found a positive covariation between the richness of cuckoos’ Ischnoceran lice and the number of their foster species, possibly due to the complex and dynamic subpopulation structure of cuckoo species that utilize several host species. We documented diversity interactions across a three‐level host parasite system and we found evidence that brood parasitism has opposing effects on louse richness at two slightly differing macroevolutionary scales, namely the species richness and the genera richness.  相似文献   
996.
Libri novi     
Ohne Zusammenfassung  相似文献   
997.
Summary Based on animal experiments a clinical study with BCG cell wall preparation (CWP) was developed. Patients with head and neck carcinomas stage T1/2N0–2M0 were randomized. One group received surgical treatment only and a second group received preoperative intralesional BCG-CWP. So far 12 patients have been included in each group. After 3 years the CCR (complete cancer remission) in the surgery only group was 39% and that in the preoperative BCG-CWP group, 69% (P=11%). The cumulative proportion of surviving patients was 50% in the surgery only and 73% in the BCG-CWP group (P=21%). BCG-CWP injection was followed by an increase in body temperature and a decrease in peripheral blood lymphocytes. No changes in liver, kidney, or other organ function could be observed after BCG-CWP therapy. Complications and severe secondary effects such as have been described for living BCG were not observed, and significant immunological changes have not been detected so far.  相似文献   
998.
Tibor  Farkas 《Ibis》1969,111(3):281-292
A preference for bushy evergreen undergrowth determines both the local and the general distribution of Cossypha natalensis. The lack of such undergrowth makes equatorial rain-forests unsuitable. Tropical and subtropical evergreen forests provide excellent conditions from this point of view, and they are thus the main habitat type from which C. natalensis has secondarily extended into tropical and subtropical deciduous forests with evergreen undergrowth.
Adult birds remain in or close to their territories throughout the year. First-year birds undertake longer movements during the winter. Breeding territories are relatively small, from 2,500 up to (exceptionally) 10,000 square yards (2,100-8,400 sq. m).
Breeding begins in October. Both sexes build the nest, but only the female incubates. In southern Africa there is one brood a year, and the care of the offspring is protracted. The juvenile moult begins in the third and ends in the sixth month; adults have only one (post-breeding) moult a year.
The begging behaviour of the young is somewhat different from that of most other turdine birds, and is considered to be more primitive. The ontogeny of the adult displays is described as observed in young birds kept in captivity.
The development of vocal behaviour is described. Special attention is given to the different functional forms of the song, and to two of its special features, imitation and a tonal quality termed vox humana.  相似文献   
999.
The same karyotype which was described previously in A. ventricosa plants from Oran, Algeria was found in plants from Cyprus and in most of the plants from the Apsheron Peninsula, U.S.S.R. This karyotype, which consists of subterminal chromosomes, was designated C v 1 . In the karyotype of about one-third of the Apsheron plants a single pair of submedian chromosomes replaced a pair of long subterminals. This karyotype was designated C v 2 . The chromosomes formed 7II at meiosis in both C v 1 C v 1 and C v 1 C v 2 hybrids regardless of geographic origin. A heteromorphic bivalent was apparent in PMCs in the C v 1 C v 2 hybrids. A pericentric inversion was postulated as the origin of the submedian pair, the C v 2 C v 2 karyotype being the inversion homozygote. The absence of duplication-deficiency gametes was inferred from the good fertility of the heterozygote. Members of the heteromorphic pair were transmitted in equal proportion and the segregates C v 1 C v 1 , C v 1 C v 2 and C v 2 C v 2 were equally fertile; thus the inversion did not handicap reproduction. The small contemporary colonies of A. ventricosa, with peripheral locations and vast distances between them, because of the full homology and interfertility, are considered remnants of a formerly large central population.Contribution No 282 from the Research Station, Central Experimental Farm, Ottawa, Ontario.This paper is dedicated to the memory of Dr. Barna Györffy, whose untimely death on August 5, 1970 ended a distinguished career that was an example of integrity and scholarship to a troubled generation of Hungarian geneticists.  相似文献   
1000.
The inhibitory effect of metal salts on the formation and transformation of E to ghosts was studied. Ferrous and ferric salts inhibited the binding of C9 to EAC1-8 cells but had no other inhibitory role in the reaction. Uranly, copper, and zinc salts inhibited the transformation of the EAC1-9inserted intermediate to E ghosts. This inhibition occurred at a stage prior to detectable damage as measured by 86Rb or hemoglobin release and at a step prior to that inhibitable by high molarity EDTA. Consequently a further step in the reaction sequence of E to ghosts was identified. The reaction sequence leading from EAC1-9 to ghosts can be summarized as follows: formula: (see text).  相似文献   
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