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41.
42.
This study presents the effect of water content in moss turves from the Windmill Islands, Wilkes Land, continental Antarctica
on the composition of associated filamentous fungi. The two most prevalent mosses were sampled: Grimmia antarctici and Bryum pseudotriquetrum. Results were expressed as dry weights. No relationship was found between water content of the mosses or the surrounding
soil and fungal diversity. Ten species of fungi were recovered and all species belong to cosmopolitan taxa.
Accepted: 21 June 1999 相似文献
43.
Charles E. Pope Betsy L. Dresser Neeoo W. Chin James H. Liu Naida M. Loskutoff Erica J. Behnke Corrine Brown Molly A. McRae Charles E. Sinoway Mark K. Campbell Kenneth N. Cameron O'Dell M. Owens Chad A. Johnson Ronald R. Evans Marcelle I. Cedars 《American journal of primatology》1997,41(3):247-260
A 21-year-old multiparous female exhibiting 31–41 day menstrual cycles was given hFSH (225 IU/day, Metrodin 75, from cycle day 3 through 9 (menses = day 1) and hCG (10,000 IU, Profasi, on day 10 to stimulate follicular development. At 35 h after hCG, under isoflurane (AErrane) anesthesia, follicles were aspirated by controlled suction under transvaginal ultrasound guidance. Metaphase II oocyctes (n = 11) were placed in modified human tubal fluid (mHTF, 100 μl) medium under oil at 37°C in humidified 5% CO2. Frozen semen, collected by voluntary ejaculation, was thawed (70°C H2O bath, 6 sec), diluted slowly, centrifuged, and resuspended in mHTF, and 160,000 motile spermatozoa/ml were added at 6 h after oocyte recovery. At 21 h postinsemination (p.i.) eight oocytes were at the two-cell stage, five were cryopreserved, and three were cultured to the six- to eight-cell stage in mHTF with granulosa cells before transcervical uterine transfer at 47 h p.i. using a Teflon catheter. Micronized progesterone (400 mg/d) was orally administered for 10 weeks posttransfer (p.t.). Ultrasound examination revealed a single fetus at 15 weeks p.t., and unassisted delivery of a live 1.37 kg female infant occurred at 29 weeks. Am. J. Primatol. 41:247–260, 1997. © 1997 Wiley-Liss, Inc. 相似文献
44.
Genetic population structure of the Greater Bilby Macrotis lagotis, a marsupial in decline 总被引:1,自引:0,他引:1
The Greater Bilby has shown a rapid decline in range during this century and now occupies only a small isolated area in south-western Queensland (QLD) and a larger, but mostly low-density area in the north-western deserts of the Northern Territory (NT) and Western Australia (WA). We have examined variation in the control region of mitochondrial DNA (mtDNA) and at nine microsatellite loci in order to investigate the extent of current and historical subdivision across the species range, and to provide a preliminary assessment of genetic structuring and mating system on a finer scale within the QLD population. Both mtDNA and microsatellite loci had substantial variation within and among populations, with mtDNA divergence being greater between QLD and NT than between NT and WA. The QLD population had two unique and divergent mtDNA lineages, but there was no evidence for strong phylogeographical structure across the range. The available evidence suggests that the bilby should be considered as a single Evolutionarily Significant Unit consisting of multiple Management Units. Augmentation of the remnant QLD population from the NT does not appear necessary at this stage, at least not on genetic grounds. Finer-scale analysis of microsatellite variation for two QLD colonies revealed a deficiency of heterozygotes and significantly greater relatedness within than between colonies. However, structuring was observed only for males; relatedness values for females did not depart from those expected under panmixia. Parentage exclusion analysis for one colony allowed the construction of a partial pedigree which indicated strong polygyny, with one male fathering all but one of the eight offspring assigned. The extent to which fine-scale genetic structuring and differences between sexes is due to sex-biased dispersal vs. effects of mating system remain to be determined. 相似文献
45.
Larsson M Duffy DL Zhu G Liu JZ Macgregor S McRae AF Wright MJ Sturm RA Mackey DA Montgomery GW Martin NG Medland SE 《American journal of human genetics》2011,(2):334-343
Human iris patterns are highly variable. The origins of this variation are of interest in the study of iris-related eye diseases and forensics, as well as from an embryological developmental perspective, with regard to their possible relationship to fundamental processes of neurodevelopment. We have performed genome-wide association scans on four iris characteristics (crypt frequency, furrow contractions, presence of peripupillary pigmented ring, and number of nevi) in three Australian samples of European descent. Both the discovery (n = 2121) and replication (n = 499 and 73) samples showed evidence for association between (1) crypt frequency and variants in the axonal guidance gene SEMA3A (p = 6.6 × 10−11), (2) furrow contractions and variants within the cytoskeleton gene TRAF3IP1 (p = 2.3 × 10−12), and (3) the pigmented ring and variants in the well-known pigmentation gene SLC24A4 (p = 7.6 × 10−21). These replicated findings individually accounted for around 1.5%–3% of the variance for these iris characteristics. Because both SEMA3A and TRAFIP1 are implicated in pathways that control neurogenesis, neural migration, and synaptogenesis, we also examined the evidence of enhancement among such genes, finding enrichment for crypts and furrows. These findings suggest that genes involved in normal neuronal pattern development may also influence tissue structures in the human iris. 相似文献
46.
Polymer-protein conjugation was performed using N-hydroxysuccinimide and aldehyde-terminated zwitterionic polymers, and the resulting polymer-protein conjugates were characterized by gel electrophoresis and fast protein liquid chromatography. Methacryloyloxyethyl phosphorylcholine (MPC) polymers were prepared by atom transfer radical polymerization in which the requisite functional end-groups for protein conjugation were embedded within the polymerization initiators. These phosphorylcholine polymers were conjugated to lysozyme as a model protein, as well as two therapeutic proteins, granulocyte colony stimulating factor (G-CSF) and erythropoietin (EPO). These MPC polymer-protein conjugates represent alternatives to PEGylated proteins, with the potential to provide improved efficacy in a therapeutic treatment relative to the protein itself. 相似文献
47.
Long-term reversible suppression of oestrus in bitches with nafarelin acetate, a potent LHRH agonist
G I McRae B B Roberts A C Worden A Bajka B H Vickery 《Journal of reproduction and fertility》1985,74(2):389-397
Adult cyclic beagle bitches were treated for up to 18 months with nafarelin acetate via subcutaneously implanted osmotic pumps, starting during the first week of a pro-oestrous vaginal discharge. The imminent ovulation appeared to be unaffected by treatment, but doses of 8 or 32 micrograms analogue/day reduced the integrated luteal progesterone values. No new oestrus was detected in 3 bitches during 18 months of treatment with 32 micrograms/day, which resulted in mean plasma levels of 0.4 ng analogue/ml. A return to oestrus was observed in all 3 bitches between 3 and 18 weeks after cessation of treatment: 2 of the bitches mated at those times and produced normal litters. Another 2 bitches were similarly treated with 32 micrograms analogue/day; they were mated at the oestrus at start of treatment and dosing was continued for about 63 days. One of the bitches conceived and produced a normal litter. Nafarelin acetate treatment begun during anoestrus resulted in an induced heat 1-2 weeks after the start of treatment. The induced heat consisted of pro-oestrous vaginal discharge, oestrous vaginal cytology, and ovulation (judged by increased circulating levels of progesterone). Three bitches mated at the induced heat and treated for the normal duration of gestation did not litter. Nafarelin treatment of 3 bitches before puberty did not induce signs of oestrus and prevented the occurrence of oestrus through 18 months of treatment. The first oestrus in these bitches occurred 3.5-4 months after cessation of treatment, but mating at that time did not result in pregnancy. These studies have established the feasibility of and dosage requirement for the use of the LHRH agonist as a contraceptive in the bitch. 相似文献
48.
The experience of the Children''s Hospital of Winnipeg from 1957 to 1971 with abused infants and children is presented with statistical data on 132 children. Details as to incidence, source and types of abuse are presented along with a discussion of the management of the problem. A follow-up study on a group of the abused children is also presented with comments directed towards some preventive measures. 相似文献
49.
Twenty-two infants in whom hypoglycemia (blood sugar less than 20 mg./100 ml.) was noted during the first few days of life were followed up when eight to 30 months of age. In eight such symptoms as muscular tremors, cyanosis, apneic spells and convulsions were associated with the hypoglycemia; five of these had abnormal central nervous system signs and retarded development. One other had possible impairment of development and another had a recurrence of hypoglycemia after having been well for four years. Fourteen of the 22 infants had no symptoms associated with the hypoglycemia, and on follow-up only two of these showed possible impairment. The rest were normal.This preliminary study suggests that hypoglycemia associated with neurological symptoms in the newborn period carries a poor prognosis with respect to permanent neurological damage. Asymptomatic hypoglycemia may have a relatively good prognosis. 相似文献
50.