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1.
The results of the examination of sputum induced by the inhalation of nebulized hypertonic saline in the diagnosis of Pneumocystis carinii pneumonia (PCP) are presented. In suspected cases of PCP in patients who were either HIV antibody positive or were receiving immunosuppressive therapy, 46 induced sputum specimens were stained using both Grocott's modified Gomori methenamine silver nitrate (GMS) and immunofluorescence staining. In 12 specimens P. carinii cysts were detected by both methods, in four specimens by GMS staining only and in five specimens by immunofluorescence only. The sensitivity of induced sputum examination in the detection of P. carinii cysts was increased by using both of these staining methods on each sputum specimen and the need for more invasive methods of diagnosis was reduced. 相似文献
2.
Morphometric comparison of populations of Orchis sitnia Lam. (Orchidaceae) from Oxfordshire and Kent
RICHARD M. BATEMAN ORPAH S. FARRINGTON 《Botanical journal of the Linnean Society. Linnean Society of London》1989,100(3):205-218
BATEMAN, R. M. & FARRINGTON, O. S., 1989. Morphometric comparison of populations of Orchis sitnia Lam. (Orchidaceae) from Oxfordshire and Kent. Univariate and multivariate morphometric analyses of Orchis simia Lam. from its two remaining naturally-founded populations in Britain (Goring, Oxfordshire and Faversham, Kent) reveal only minor morphological differences between the populations and suprisingly low levels of intra-population variation. This probably reflects recent founding from Continental seed at Faversham and penecontemporaneous, human-induced, catastrophic contraction of the gene pool at Goring. The apparently restricted gene pools of these populations may adversely effect their long-term survival. 相似文献
3.
Goats and some sheep synthesize a juvenile hemoglobin, Hb C (alpha 2 beta
C2), at birth and produce this hemoglobin exclusively during severe anemia.
Sheep that synthesize this juvenile hemoglobin are of the A haplotype.
Other sheep, belonging to a separate group, the B haplotype, do not
synthesize hemoglobin C and during anemia continue to produce their adult
hemoglobin. To understand the basis for this difference we have determined
the structural organization of the beta- globin locus of B-type sheep by
constructing and isolating overlapping genomic clones. These clones have
allowed us to establish the linkage map 5' epsilon I-epsilon II-psi beta
I-beta B-epsilon III-epsilon IV- psi beta II-beta F3' in this haplotype.
Thus, B sheep lack four genes, including the BC gene, and have only eight
genes, compared with the 12 found in the goat globin locus. The goat
beta-globin locus is as follows: 5' epsilon I-epsilon II-psi beta X-beta
C-epsilon III-epsilon IV-psi beta Z-beta A-epsilon V-epsilon VI-psi beta
Y-beta F3'. Southern blot analysis of A-type sheep reveals that these
animals have a beta- globin locus similar to that of goat, i.e., 12 globin
genes. Thus, the beta-globin locus of B-haplotype sheep resembles that of
cows and may have retained the duplicated locus of the ancestor of cows and
sheep. Alternatively, the B-sheep locus arrangement may be the result of a
deletion of a four-gene set from the triplicated locus.
相似文献
4.
The enhanced infectivity of Metarhizium flavoviride in oil formulations to desert locusts at low humidities 总被引:2,自引:0,他引:2
Formulation in non-evaporative diluents such as oils is required to exploit the advantages of controlled droplet application methods for biopesticides based on conidial suspensions of entomopathogenic fungi. In laboratory assays on desert locusts (Schistocerca gregaria), formulations of Metarhizium flauoviride conidia in cotton seed oil showed superior performance to water-based suspensions and this was especially pronounced at low humidities (35% r.h.). The LD50s for oil and water suspensions at 5 days were 8900 and > 106 conidia/insect respectively. The dose-mortality regression line for oil was more than four times steeper and median lethal times were typically 76% of those for aqueous suspensions. Formulation in oil improves the efficacy of this fungus and may extend the application of species with lipophilic conidia into less humid agricultural environments. 相似文献
5.
6.
Eyespot was assessed and grain yields determined in the eighth and ninth years (1992 and 1993) of a field experiment in which the fungicides carbendazim and prochloraz were applied, separately or in mixtures, to plots of successive crops of winter wheat. Populations of the eyespot fungus, Pseudocercosporella herpotrichoides, were characterised by the proportions of cultures grown on agar from infected stems that were W-type or R-type, or were carbendazim-resistant or carbendazim-sensitive. Sensitivity to prochloraz in agar was determined for isolates from populations sampled in 1992 using restricted maximum likelihood analysis of EC50s (concentrations needed to decrease colony growth by 50%), to deal with the unbalanced data, and comparisons were made by Wald statistics. Control by prochloraz was maintained but in 1992, as in some previous years, its application with carbendazim was more effective than its application alone. Selection by prochloraz for strains sensitive to carbendazim continued to occur and may have contributed to its sometimes relatively poorer performance in the absence of carbendazim. R-type isolates taken from prochloraz-treated plots, with or without carbendazim, in 1992 were less sensitive to prochloraz than were isolates from plots untreated with prochloraz. There was evidence of a greater range of sensitivities to prochloraz in R-type than in W-type isolates (although some uncertainty results from the small numbers of W-type isolates obtained from some treatments), which would explain the selection of the R-type by prochloraz. The significance of these findings to modern wheat growing practices is considered. 相似文献
7.
G. L. BATEMAN 《The Annals of applied biology》1984,104(3):459-465
Soil treatment fungicides were tested against take-all (Gaeumannomyces graminis var. tritici) in three field experiments with winter wheat. Fungicides were applied as drenches either before sowing in autumn, and incorporated by rotary harrowing, or to the crop in spring. The most effective treatments were autumn applied benomyl (20 kg/ha) and nuarimol (0·55-4·4 kg/ha). However, the highest nuarimol concentration depressed yield. Benomyl sometimes induced a resurgence of take-all in the second wheat crop after treatment. Nuarimol had no adverse effects in subsequent crops, and neither fungicide hindered the onset of take-all decline in a third crop after treatment. The possible value of soil treatment in future control strategies is discussed. 相似文献
8.
Decreased severity of potato common scab after foliar sprays of 3,5 -dichlorophenoxyacetic acid, a possible antipathogenic agent 总被引:1,自引:0,他引:1
BY A. H. MCINTOSH G. L. BATEMAN K. CHAMBERLAIN G. W. DAWSON M. M. BURRELL 《The Annals of applied biology》1981,99(3):275-281
Glasshouse tests on the potato cultivars Majestic and Maris Bard measured the effects of single early foliar sprays of ring-substituted phenoxyacetic acids (0.9 × 10–3 M) on the incidence of potato common scab, caused by soil-borne Streptomyces scabies. The most effective compound was 3,5-dichlorophenoxyacetic acid (3,5-D), which decreased scab by about 90%; its action was preventative, early sprays being more effective than late However, it slightly decreased yield, and increased the number of tubers per plant and the proportion of deformed tubers. The trichloro- and tetrachloro- acids containing the 3,5-dichloro- group also decreased scab, though to lesser extents; the most active of these was the 2,3,4,5-tetrachloro- acid, which had the same side effects as 3,5-D. The herbicide 2,4-D almost halved scab incidence, but seriously decreased yield. Other acids tested had little or no effect on scab. In tests against S. scabies in culture, 3,5-D was no more toxic than other disubstituted acids which were inactive, or weakly active, against the disease in vivo. 3,5-D may be an ‘antipathogenic agent’, preventing scab development by altering tuber metabolism. 相似文献
9.
Calcrete aquifers from the Yilgarn region of arid central Western Australia contain an assemblage of obligate groundwater invertebrate species that are each endemic to single aquifers. Fine-scale phylogeographic and population genetic analyses of three sympatric and independently derived species of amphipod (Chiltoniidae) were carried out to determine whether there were common patterns of population genetic structure or evidence for past geographic isolation of populations within a single calcrete aquifer. Genetic diversity in amphipod mitochondrial DNA (cytochrome c oxidase subunit I gene) and allozymes were examined across a 3.5 km2 region of the Sturt Meadows calcrete, which contains a grid of 115 bore holes (=wells). Stygobiont amphipods were found to have high levels of mitochondrial haplotype diversity coupled with low nucleotide diversity. Mitochondrial phylogeographic structuring was found between haplogroups for one of the chiltoniid species, which also showed population structuring for nuclear markers. Signatures of population expansion in two of the three species, match previous findings for diving beetles at the same site, indicating that the system is dynamic. We propose isolation of populations in refugia within the calcrete, followed by expansion events, as the most likely source of intraspecific genetic diversity, due to changes in water level influencing gene flow across the calcrete. 相似文献
10.
Holger?J?SchünemannEmail author Brydon?JB?Grant Paola?Muti Susan?E?McCann Deepa?Kudalkar Malathi?Ram Tom?Nochajski Marcia?Russell Maurizio?Trevisan 《BMC pulmonary medicine》2002,2(1):3