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61.
J F Quirke J J Jennings J P Hanrahan J P Gosling 《Journal of reproduction and fertility》1979,56(2):479-488
The influence of Gn-RH, hCG and a PMSG-hCG mixture (PG600) on the time of ovulation, ovulation rate and on the occurrence of oestrus in ewes treated with progestagen-impregnated sponges for 12 days examined. The effects of Gn-RH analogues on plasma LH, oestrus, ovulation and conception rate were also investigated. Six separate experiments were carried out. When 50 micrograms Gn-RH were given 24 h after sponge removal ovulation occurred in 44--46% of ewes within 24 h and in all ewes by 34 h. Gn-RH was a more potent ovulation synchronizer than hCG. Both hCG and PG600 reduced the incidence of overt oestrus. Gn-RH also had this effect in ewes treated during February and May but not in August and September. Gn-RH analogues given 2 days before sponge removal significantly increased ovulation rate. The display of oestrus was not affected in ewes treated 2 days before sponge removal but was suppressed in 43-69% of ewes treated with an analogue at the time of sponge removal. Ovulation occurred in 50-62% of ewes within 30-35 h of injection of Gn-RH analogues, regardless of the time of their administration. The release of LH in response to one analogue was not influenced by the presence of the progestagen-impregnated sponge in the vagina. When given a Gn-RH analogue 2 days before sponge removal or at the time of sponge removal 63 and 62% of mated ewes became pregnant compared with 70% of control ewes. 相似文献
62.
R.P. Smith V. Andres F. Martelli B. Gosling F. Marco‐Jimenez K. Vaughan M. Tchorzewska R. Davies 《Journal of applied microbiology》2018,124(1):274-285
Aims
The control of Salmonella in pig production is necessary for public and animal health, and vaccination was evaluated as a strategy to decrease pig prevalence.Methods and Results
The study examined the efficacy of a live Salmonella Typhimurium vaccine, administered to sows on eight commercial farrow‐to‐finish herds experiencing clinical salmonellosis or Salmonella carriage associated with S. Typhimurium or its monophasic variants. Results of longitudinal Salmonella sampling were compared against eight similarly selected and studied control farms. At the last visit (~14 months after the start of vaccination), when all finishing stock had been born to vaccinated sows, both faecal shedding and environmental prevalence of Salmonella substantially declined on the majority of vaccinated farms in comparison to the controls. A higher proportion of vaccine farms resolved clinical salmonellosis than controls. However, Salmonella counts in positive faeces samples were similar between nonvaccinated and vaccinated herds.Conclusions
The results suggest that maternal vaccination is a suitable option for a Salmonella Typhimurium reduction strategy in farrow‐to‐finish pig herds.Significance and Impact of the Study
Salmonella vaccines have the potential to reduce the prevalence of Salmonella in pigs and result in a reduction of human cases attributed to pork. 相似文献63.
Summary Light and electron microscopic techniques have been employed to study the arrangement and distribution of two types of muscle in the upper urinary tract of the rat. An outer layer of cells has been identified in the wall of the renal calix and pelvis. These cells are separated by connective tissue but possess numerous processes which make close contacts with adjacent cells. A layer of similar cells has not been observed in the wall of the upper ureter. The inner layer of muscle in the calix and pelvis is composed of larger cells similar to and apparently continuous with ureteric muscle. These cells are closely related to one another without intervening connective tissue and possess numerous bundles of myofilaments which extend along the length of the cell. The two types of muscle are closely related and, in the junctional region, cells of the outer layer are arranged along the length and make close contacts with one or more of the inner smooth muscle cells. A quantitative estimation has been made of nerve bundles associated with smooth muscle forming the outer layer of the calix and pelvis and with the muscle of the ureter. The results have shown a five fold increase in nerves associated with the caliceal muscle when compared with the ureter. The results are discussed in relation to the concept of a ureteric pacemaker.The authors wish to thank Professor G. A. G. Mitchell for his useful advice and encouragement. 相似文献
64.
Population genetic structure of mussels from the Baltic Sea 总被引:2,自引:0,他引:2
In a macrogeographic survey, the population genetic structure of mussels from various regions of the Baltic Sea, a large semi-enclosed
brackish-water basin, was examined with reference toMytilus edulis andM. galloprovincialis samples from the North Sea, Irish coast and southern Portugal. Electrophoretically detectable variation was analysed at 6
polymorphic enzyme loci (Ap, Est-D, Lap-2, Odh, Pgi andPgm). Evidence was provided of a remarkably large amount of biochemical genetic differentiation among ecologically and morphologically
divergent mussel populations in the Baltic. Patterns of allele frequencies in low-salinity populations from the area of the
Baltic Proper were demonstrated to be widely homogeneous but contrast strongly with those of the western Baltic, the latter
resembling populations from marine habitats of the North Sea. Associated with a pronounced salinity gradient, the spatial
heterogeneity in gene-pool structure is indicated by steep clines of allele frequency changes in the area of the eastern Danish
isles. The adaptive significance of the observed allozymic variation is suggested. From genetic distance estimates, the subdivision
of population structure is discussed in relation to the significant amount of differentiation detected withinMytilus populations to date and to the evolutionary time required for the divergence of Baltic mussel populations. The allozymic
data provide evidence for the genetic distinctiveness of mussels from the low-salinity areas of the Baltic. Their position
at the specific or subspecific level of classification requires further consideration. 相似文献
65.
ABSTRACT: BACKGROUND: Policy makers have speculated that one of the economic benefits of malaria elimination includes increases in foreign direct investment, particularly tourism. METHODS: The study examines the empirical relationship between the demand for travel and malaria cases in two countries with large tourism industries around the time in which they carried out malaria-elimination campaigns. In Mauritius, this analysis examines historical yearly tourist arrivals and malaria cases from 1978-1999, accounting for the background secular trend of increasing international travel. In Dominican Republic, a country embarking upon malaria elimination, it employs a time-series analyses of the monthly, international, tourist arrivals from 1998-2010 to determine whether the timing of significant deviations in tourist arrivals coincides with malaria outbreaks. RESULTS: While naive relationships exist in both cases, the results show that the relationships between tourist arrival and malaria cases are relatively weak and statistically insignificant once secular confounders are accounted for. CONCLUSIONS: This suggests that any economic benefits from tourism that may be derived from actively pursuing elimination in countries that may have high tourism potential are likely to be small when measured at a national level. Rather, tourism benefits are likely to be experienced with greater impact in more concentrated tourist areas within countries, and future studies should seek to assess this relationship at a regional or local level. 相似文献
66.
The musculature of the upper urinary tract 总被引:1,自引:0,他引:1
J A Gosling 《Acta anatomica》1970,75(3):408-422
67.
68.
William D. Gosling Francis E. Mayle Nicholas J. Tate Timothy J. Killeen 《Review of Palaeobotany and Palynology》2009,153(1-2):70-85
Accurate differentiation between tropical forest and savannah ecosystems in the fossil pollen record is hampered by the combination of: i) poor taxonomic resolution in pollen identification, and ii) the high species diversity of many lowland tropical families, i.e. with many different growth forms living in numerous environmental settings. These barriers to interpreting the fossil record hinder our understanding of the past distributions of different Neotropical ecosystems and consequently cloud our knowledge of past climatic, biodiversity and carbon storage patterns. Modern pollen studies facilitate an improved understanding of how ecosystems are represented by the pollen their plants produce and therefore aid interpretation of fossil pollen records. To understand how to differentiate ecosystems palynologically, it is essential that a consistent sampling method is used across ecosystems. However, to date, modern pollen studies from tropical South America have employed a variety of methodologies (e.g. pollen traps, moss polsters, soil samples). In this paper, we present the first modern pollen study from the Neotropics to examine the modern pollen rain from moist evergreen tropical forest (METF), semi-deciduous dry tropical forest (SDTF) and wooded savannah (cerradão) using a consistent sampling methodology (pollen traps). Pollen rain was sampled annually in September for the years 1999–2001 from within permanent vegetation study plots in, or near, the Noel Kempff Mercado National Park (NKMNP), Bolivia. Comparison of the modern pollen rain within these plots with detailed floristic inventories allowed estimates of the relative pollen productivity and dispersal for individual taxa to be made (% pollen/% vegetation or ‘p/v’). The applicability of these data to interpreting fossil records from lake sediments was then explored by comparison with pollen assemblages obtained from five lake surface samples.Pollen productivity is demonstrated to vary inter-annually and conforms to a consistent hierarchy for any given year: METF > SDTF > cerradão. This suggests an association between pollen productivity and basic structural characteristics of the ecosystem, i.e. closed canopy vs. open canopy vs. savannah. Comparison of modern pollen and vegetation revealed that some important floristic elements were completely absent from the pollen: Qualea and Erisma (METF), Bauhinia, Simira and Guazuma (SDTF), and Pouteria and Caryocar (cerradão). Anadenanthera was found to be abundant in both the pollen and flora of SDTF (p/v = 3.6), while Poaceae was relatively poorly represented in cerradão (0.2). Moraceae, Cecropia and Schefflera were found to be over-represented palynologically in all ecosystems. Overall, the data demonstrated that no one taxon could be used as a definitive indicator of any of the ecosystems. Instead, associations of taxa were found to be important: METF = Moraceae (> 40%), Cecropia, Hyeronima, Celtis; SDTF = Anadenanthera, Apuleia, Ferdinandusa and non-arboreal Asteraceae, Bromeliaceae, Piper and fern spores; cerradão = Poaceae, Myrtaceae, Borreria, Solanum plus Asteraceae and fern spores. Interpretation of Poaceae pollen was highlighted as problematic, with relatively low abundance in the cerradão (< 20%) in comparison to high abundance in lake environments (c. 30–50%). Re-examination of fossil pollen records from NKMNP revealed that modern vegetation associations were only established in the last few thousand years. 相似文献
69.
Jamie T. Griffin Matthew Cairns Azra C. Ghani Cally Roper David Schellenberg Ilona Carneiro Robert D. Newman Martin P. Grobusch Brian Greenwood Daniel Chandramohan Roly D. Gosling 《PloS one》2010,5(9)
Background
Intermittent Preventive Treatment of malaria in infants using sulfadoxine-pyrimethamine (SP-IPTi) is recommended by WHO for implementation in settings where resistance to SP is not high. Here we examine the relationship between the protective efficacy of SP-IPTi and measures of SP resistance.Methods and Results
We analysed the relationship between protective efficacy reported in the 7 SP-IPTi trials and contemporaneous data from 6 in vivo efficacy studies using SP and 7 molecular studies reporting frequency of dhfr triple and dhps double mutations within 50km of the trial sites. We found a borderline significant association between frequency of the dhfr triple mutation and protective efficacy to 12 months of age of SP-IPTi. This association is significantly biased due to differences between studies, namely number of doses of SP given and follow up times. However, fitting a simple probabilistic model to determine the relationship between the frequency of the dhfr triple, dhps double and dhfr/dhps quintuple mutations associated with resistance to SP and protective efficacy, we found a significant inverse relationship between the dhfr triple mutation frequency alone and the dhfr/dhps quintuple mutations and efficacy at 35 days post the 9 month dose and up to 12 months of age respectively.Conclusions
A significant relationship was found between the frequency of the dhfr triple mutation and SP-IPTi protective efficacy at 35 days post the 9 month dose. An association between the protective efficacy to 12 months of age and dhfr triple and dhfr/dhps quintuple mutations was found but should be viewed with caution due to bias. It was not possible to define a more definite relationship based on the data available from these trials. 相似文献70.
Lesong Conteh Elisa Sicuri Fatuma Manzi Guy Hutton Benson Obonyo Fabrizio Tediosi Prosper Biao Paul Masika Fred Matovu Peter Otieno Roly D. Gosling Mary Hamel Frank O. Odhiambo Martin P. Grobusch Peter G. Kremsner Daniel Chandramohan John J. Aponte Andrea Egan David Schellenberg Eusebio Macete Laurence Slutsker Robert D. Newman Pedro Alonso Clara Menéndez Marcel Tanner 《PloS one》2010,5(6)