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151.
Janette Wallis 《International journal of primatology》1995,16(3):435-451
Although wild chimpanzees are not seasonal breeders, there are seasonal effects on several aspects of chimpanzee reproduction.
I examined the seasonal incidence of anogenital swelling in cyclic, pregnant, and acyclic female chimpanzees in Gombe National
Park, May 1975–April 1992, and surveyed important reproductive events to determine whether there is a seasonal effect. I analyzed
data by season (wet vs. dry) and seasonal quarter;early dry season = May–July;late dry = August–October;early wet = November–January;late wet = February–April. When data for the 17 years are combined, the percentage of females in each reproductive state remains
consistent throughout the year. In a given month, 30–35% of subjects were in the cyclic category, 11–15% were pregnant, and
54–61% were acyclic. Cyclic females showed full swelling more often during the late dry season. Pregnant females exhibited
anogenital swelling more often during the late dry and early wet seasons. Acyclic females also exhibited a seasonal effect
with more anogenital swelling during the late dry season. There is no seasonal difference in frequency of live births (dry,
20;wet, 23). However, the timing of conception showed a seasonal effect (dry, 32;wet, 16). Consistent with earlier reports, the onset of postpartum cycles is highly seasonal;30 occurred during dry season, 9 during wet season. The occurrence of first full swellings for young females is also concentrated
in the late dry season. It appears that the dry season is a time of great change for Gombe chimpanzee reproductive physiology.
Previous studies indicated that seasonal changes in food availability play a role in increasing group size during the dry
season and social contact between females can enhance cyclicity. Accordingly, I suggest that seasonal changes in diet may
play a role, either directly (food content) or indirectly (social contact), to alter reproductive physiology. 相似文献
152.
Steven C. Wallis Bruce G. Charles Lawrence R. Gahan 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1995,674(2)
A rapid and economical high-performance liquid chromatographic assay is described for norfloxacin in serum. Samples (100 μl) containing N-ethylnorfloxacin as the internal standard were extracted into 1 ml of chloroform. Chromatography was performed at 30°C on a 40×3.2 mm I.D. C18 guard cartridge (3 μm spherical particles) using a mobile phase of 11% (v/v) acetonitrile in 0.01 M phosphate buffer (pH 2.5) containing 0.001 M triethylamine, and pumped at 1 ml/min. Detection was at 279 nm. The retention times of norfloxacin and internal standard were 1.9 and 2.9 min, respectively. Calibration curves were linear (r>0.999) from 0.1 mg/l to at least 2.0 mg/l. Within-day and between-day precision (C.V.) were 8.6% or less, and accuracy was 5.3% or less. Absolute assay recovery of norfloxacin was over 70%. 相似文献
153.
James G. Wallis Katarzyna Dziewanowska Daniel J. Guerra 《Molecular breeding : new strategies in plant improvement》1996,2(3):283-290
Selection of transformed plants is a fundamental requirement for plant molecular breeding. We have developed the use of thesulI gene, whose application has already been described in tobacco [17] for selection in the important potato cultivar Russet Burbank. We found that theSulI marker is highly effective, with efficiency comparable to that ofnptII. Analysis of the effect of thesulI gene on folate metabolism in Russet Burbank under sulfa drug selection demonstrates thatsulI may be an important tool for analysis of folate metabolism in plants. 相似文献
154.
155.
Douglas G. Ward Laura Baxter Naheema S. Gordon Sascha Ott Richard S. Savage Andrew D. Beggs Jonathan D. James Jennifer Lickiss Shaun Green Yvonne Wallis Wenbin Wei Nicholas D. James Maurice P. Zeegers KK Cheng Glenn M. Mathews Prashant Patel Michael Griffiths Richard T. Bryan 《PloS one》2016,11(2)
Background
Highly sensitive and specific urine-based tests to detect either primary or recurrent bladder cancer have proved elusive to date. Our ever increasing knowledge of the genomic aberrations in bladder cancer should enable the development of such tests based on urinary DNA.Methods
DNA was extracted from urine cell pellets and PCR used to amplify the regions of the TERT promoter and coding regions of FGFR3, PIK3CA, TP53, HRAS, KDM6A and RXRA which are frequently mutated in bladder cancer. The PCR products were barcoded, pooled and paired-end 2 x 250 bp sequencing performed on an Illumina MiSeq. Urinary DNA was analysed from 20 non-cancer controls, 120 primary bladder cancer patients (41 pTa, 40 pT1, 39 pT2+) and 91 bladder cancer patients post-TURBT (89 cancer-free).Results
Despite the small quantities of DNA extracted from some urine cell pellets, 96% of the samples yielded mean read depths >500. Analysing only previously reported point mutations, TERT mutations were found in 55% of patients with bladder cancer (independent of stage), FGFR3 mutations in 30% of patients with bladder cancer, PIK3CA in 14% and TP53 mutations in 12% of patients with bladder cancer. Overall, these previously reported bladder cancer mutations were detected in 86 out of 122 bladder cancer patients (70% sensitivity) and in only 3 out of 109 patients with no detectable bladder cancer (97% specificity).Conclusion
This simple, cost-effective approach could be used for the non-invasive surveillance of patients with non-muscle-invasive bladder cancers harbouring these mutations. The method has a low DNA input requirement and can detect low levels of mutant DNA in a large excess of normal DNA. These genes represent a minimal biomarker panel to which extra markers could be added to develop a highly sensitive diagnostic test for bladder cancer. 相似文献156.
A hyper-recombination mutation in S. cerevisiae identifies a novel eukaryotic topoisomerase 总被引:51,自引:0,他引:51
A hyper-recombination mutation was isolated that causes an increase in recombination between short repeated delta sequences surrounding the SUP4-omicron gene in S. cerevisiae. The wild-type copy of this gene was cloned by complementation of one of its pleiotropic phenotypes, slow growth. DNA sequence of the clone revealed a 656 amino acid open reading frame capable of encoding a protein homologous to the bacterial type I topoisomerase. No homology was detected with previously identified eukaryotic topoisomerases. Construction of double mutants with either of the two known yeast topoisomerase genes revealed synergistic effects on growth suggesting overlapping functions. Expression of bacterial topoisomerase I in yeast can fully complement the slow growth defect of a null mutation. We have named this locus TOP3 and suggest that it defines a novel eukaryotic topoisomerase gene. 相似文献
157.
Isolation and partial characterization of an extradiol non-haem iron dioxygenase which preferentially cleaves 3-methylcatechol. 总被引:6,自引:0,他引:6 下载免费PDF全文
A purification procedure has been developed for an extradiol dioxygenase expressed in Escherichia coli, which was originally derived from a Pseudomonas putida strain able to grow on toluidine. Physical and kinetic properties of the enzyme have been investigated. The enzyme has a subunit Mr of 33,500 +/- 2000 by SDS/polyacrylamide-gel electrophoresis. Gel filtration indicates a molecular mass under non-denaturing conditions of 120,000 +/- 20,000. The N-terminal sequence (35 residues) of the enzyme has been determined and exhibits 50% identity with other extradiol dioxygenases. Fe(II) is a cofactor of the enzyme, as it is for other extradiol dioxygenases. The reactivity of this enzyme towards catechol and methyl-substituted catechols is somewhat different from that seen for other catechol 2,3-dioxygenases, with 3-methylcatechol cleaved at a higher rate than catechol or 4-methylcatechol. Km values for these substrates with this enzyme are all around 0.3 microM. The enzyme exhibits a bell-shaped pH profile with pKa values of 6.9 +/- 0.1 and 8.7 +/- 0.1. These results are compared with those found for other extradiol dioxygenases. 相似文献
158.
Identity and Origin of the ATPase activity associated with neuronal microtubules. I. The ATPase activity is associated with membrane vesicles 总被引:8,自引:6,他引:2 下载免费PDF全文
Microtubule protein purified from brain tissue by cycles of in vitro assembly-disassembly contains ATPase activity that has been postulated to be associated with microtubule-associated proteins (MAPs) and therefore significant for studies of microtubule-dependent motility. In this paper we demonstrate that greater than 90% of the ATPase activity is particulate in nature and may be derived from contaminating membrane vesicles. We also show that the MAPs (MAP-1, MAP-2, and tau factors) and other high molecular weight polypeptides do not contain significant amounts of ATPase activity. These findings do not support the concept of "brain dynein" or of MAPs with ATPase activity. 相似文献
159.
Cellulose nitrate membranes were used as one of the adsorbents in concentrating viruses from water. For adsorption to occur, salts were required. With increase in valency of salt, less salt was necessary for enhanced virus adsorption to membranes. Trivalent salts were more effective because they could be used at only 1% the concentration required for divalent salts. Thus, 0.5 mM AlCl(3) was as effective as 50 mM MgCl(2). For testing 500 gal of water, only 0.24 kg of AlCl(3) was required in contrast to 20 kg of MgCl(2). Virus could then be eluted from such membranes, having an area of 486 cm(2), with 250 ml of pH 11.5 buffer. Lowering the pH of the eluate and adding AlCl(3) permitted the virus to be quickly readsorbed on a smaller cellulose membrane, i.e., 4 cm(2). Virus for assay was eluted from the small membrane in 1 ml. This procedure has provided the basis for concentrating minute amounts of virus from large volumes of water. 相似文献
160.
Human sera from patients with culturally confirmed listeriosis were tested for immunoglobulin M (IgM) and immunoglobulin G (IgG) agglutinating antibodies with trypsinized antigens of Listeria monocytogenes, Streptococcus faecalis, and Staphylococcus aureus. The response of humans to listeria infections is mainly IgM rather than IgG as found in animals. The antigens prepared from L. monocytogenes serotypes 1a, 1b, 2, 4b, and 4d were evaluated for specificity with normal sera, sera from patients with various other diseases, and sera from patients with listeriosis. The trypsinized antigens appeared to be specific for listeria antibodies with a cross-reaction rate of from 5.4 to 6%. Cross-reaction with S. aureus can be eliminated by absorption of the serum with S. aureus. This agglutination technique appears to be applicable for diagnostic testing, but, as with all serological procedures, both acute and convalescent sera should be tested. 相似文献