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61.
62.
In the newer concept of the anatomical divisions of the lungs, the bronchopulmonary segment is the primary unit. Specific lung areas are identified by their relationship to the branch of the bronchus that serves them. The left upper lobe apical segment, for example, is that which is supplied by the left upper lobe apical bronchus. The boundaries of the segments are definitive; thin tissue surrounds each segment. Some diseases of the lungs tend to progress only "through channels"-reaching a segment via the specific airway serving it, and then frequently remaining within the segmental boundaries. The concept is of particular importance to surgeons because of the trend toward segmental resection and salvage of vital lung tissue. In addition, a more definitive nomenclature, useful to surgeons, internists, radiologists and bronchoscopists in designating the location of a lesion or a foreign body, is possible. 相似文献
63.
P J MANSFIELD D W WILSON † M C HEATH P J SAUNDERS 《The Annals of applied biology》1997,131(2):245-258
Pea bacterial blight occurred by natural infection in a field trial on peas in 1995. Disease development in the winter cultivars Rafale, Frilene and Froidure was compared with that in the spring cultivars Baccara, Conquest and Bohatyr, each sown on six dates in October, November, December, mid-March, late March and April. Disease incidence had reached 100% plants affected in all treatments by mid-July. Disease severity was greater in winter-sown (October, November or December) than in spring-sown peas of each cultivar at each assessment. Significant (P < 0.05) differences in disease severity occurred between cultivars in the winter-sown plots in May and June and the spring cultivars were affected more severely than the winter cultivars. Comparison of areas under the disease progress curves for both disease incidence and severity also showed that the winter-sown peas were more affected by disease than spring-sown peas and that spring cultivars were more severely affected than winter cultivars. Yield was strongly correlated with disease severity. A linear regression model suggested that, for peas sown in October, November or December, a yield loss of 0.5 tha-1 occurred for each 10% increase in canopy area affected by pea bacterial blight. 相似文献
64.
Rezzi S Cavaleiro C Bighelli A Salgueiro L da Cunha AP Casanova J 《Biochemical Systematics and Ecology》2001,29(2):179-188
The composition of 50 samples of essential oil of individual plants of Juniperus phoenicea subsp. turbinata from Corsica was investigated by GC, GC-MS and 13C NMR. alpha-Pinene, beta-phellandrene, alpha-terpinyl acetate, Delta-3-carene, myrcene and alpha-phellandrene were found to be the main constituents. The results were submitted to cluster analysis and discriminant analysis which allowed two groups of essential oils to be distinguished with respect to the content of alpha-pinene, beta-phellandrene and alpha-terpinyl acetate. 相似文献
65.
DAVID S. SAUNDERS 《Physiological Entomology》2009,34(4):301-308
This review discusses possible evolutionary trends in insect photoperiodism, mainly from a chronobiological perspective. A crucial step was the forging of a link between the hormones regulating diapause and the systems of biological rhythms, circadian or circannual, which have independently evolved in eukaryotes to synchronize physiology and behaviour to the daily cycles of light and darkness. In many of these responses a central feature is that the circadian system resets to a constant phase at the beginning of the subjective night, and then ‘measures’ the duration of the next scotophase. In ‘external coincidence’, one version of such a clock, light now has a dual role. First, it serves to entrain the circadian system to the stream of pulses making up the light/dark cycle and, second, it regulates the nondiapause/diapause switch in development by illuminating/not illuminating a specific light sensitive phase falling at the end of the critical night length. Important work by A. D. Lees on the aphid Megoura viciae using so‐called ‘night interruption experiments' demonstrates that pulses falling early in the night lead to long‐day effects that are reversible by a subsequent dark period longer than the critical night length and also show maximal sensitivity in the blue–green range of the spectrum. Pulses falling in the latter half of the night, however, produce long‐day effects that are irreversible by a subsequent long‐night and show a spectral sensitivity extending into the red. With movement to higher latitudes, insects develop genetic clines in various parameters, including critical night length, the number of long‐night cycles needed for diapause induction, the strength of the response, and the ‘depth’ or intensity of the diapause thus induced. Evidence for these and other types of photoperiodic response suggests that they provided strong selective advantages for insect survival. 相似文献
66.
Background
Many studies have provided algorithms or methods to assess a statistical significance in quantitative proteomics when multiple replicates for a protein sample and a LC/MS analysis are available. But, confidence is still lacking in using datasets for a biological interpretation without protein sample replicates. Although a fold-change is a conventional threshold that can be used when there are no sample replicates, it does not provide an assessment of statistical significance such as a false discovery rate (FDR) which is an important indicator of the reliability to identify differentially expressed proteins. In this work, we investigate whether differentially expressed proteins can be detected with a statistical significance from a pair of unlabeled protein samples without replicates and with only duplicate LC/MS injections per sample. A FDR is used to gauge the statistical significance of the differentially expressed proteins. 相似文献67.
LINLIN ZHOU YVONNE C. F. SU PIYA CHALERMGLIN RICHARD M. K. SAUNDERS 《Botanical journal of the Linnean Society. Linnean Society of London》2010,163(1):33-43
An extended molecular phylogenetic analysis of Uvaria (Annonaceae) is presented, using maximum parsimony, maximum likelihood and Bayesian methods, based on sequences of four plastid DNA regions (matK, psbA‐trnH spacer, rbcL and trnL‐F). The additional taxa include the monotypic West African genus Balonga, the monotypic South‐East Asian genus Dasoclema and seven Australian representatives of the genus Melodorum. The results indicate that all of these taxa are nested within a well‐supported clade otherwise consisting of Uvaria species, indicating that their taxonomic treatment needs to be reassessed. The distinguishing morphological characteristics of the taxa are re‐evaluated and interpreted as specialized adaptations of the basic Uvaria structure. The genus Uvaria is accordingly extended following the transfer of these species, necessitating six new nomenclatural combinations and two replacement names. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163 , 33–43. 相似文献
68.
Sequence and structure of Brassica rapa chromosome A3 总被引:1,自引:0,他引:1
Jeong-Hwan Mun Soo-Jin Kwon Young-Joo Seol Jin A Kim Mina Jin Jung Sun Kim Myung-Ho Lim Soo-In Lee Joon Ki Hong Tae-Ho Park Sang-Choon Lee Beom-Jin Kim Mi-Suk Seo Seunghoon Baek Min-Jee Lee Ja Young Shin Jang-Ho Hahn Yoon-Jung Hwang Ki-Byung Lim Jee Young Park Jonghoon Lee Tae-Jin Yang Hee-Ju Yu Ik-Young Choi Beom-Soon Choi Su Ryun Choi Nirala Ramchiary Yong Pyo Lim Fiona Fraser Nizar Drou Eleni Soumpourou Martin Trick Ian Bancroft Andrew G Sharpe Isobel AP Parkin Jacqueline Batley Dave Edwards Beom-Seok Park 《Genome biology》2010,11(9):1-12
Background
The species Brassica rapa includes important vegetable and oil crops. It also serves as an excellent model system to study polyploidy-related genome evolution because of its paleohexaploid ancestry and its close evolutionary relationships with Arabidopsis thaliana and other Brassica species with larger genomes. Therefore, its genome sequence will be used to accelerate both basic research on genome evolution and applied research across the cultivated Brassica species.Results
We have determined and analyzed the sequence of B. rapa chromosome A3. We obtained 31.9 Mb of sequences, organized into nine contigs, which incorporated 348 overlapping BAC clones. Annotation revealed 7,058 protein-coding genes, with an average gene density of 4.6 kb per gene. Analysis of chromosome collinearity with the A. thaliana genome identified conserved synteny blocks encompassing the whole of the B. rapa chromosome A3 and sections of four A. thaliana chromosomes. The frequency of tandem duplication of genes differed between the conserved genome segments in B. rapa and A. thaliana, indicating differential rates of occurrence/retention of such duplicate copies of genes. Analysis of 'ancestral karyotype' genome building blocks enabled the development of a hypothetical model for the derivation of the B. rapa chromosome A3.Conclusions
We report the near-complete chromosome sequence from a dicotyledonous crop species. This provides an example of the complexity of genome evolution following polyploidy. The high degree of contiguity afforded by the clone-by-clone approach provides a benchmark for the performance of whole genome shotgun approaches presently being applied in B. rapa and other species with complex genomes. 相似文献69.
Simon Brooker Archie CA Clements Peter J Hotez Simon I Hay Andrew J Tatem Donald AP Bundy Robert W Snow 《Malaria journal》2006,5(1):1-8
Background
On the island of Bioko (Equatorial Guinea), insecticide-treated nets (ITNs) have been the main tool used to control malaria over the last 13 years. In 2004, started an indoor residual spraying (IRS) campaign to control malaria. The purpose of this study is to asses the impact of the two control strategies on the island of Bioko (Equatorial Guinea), with regards to Plasmodium infection and anaemia in the children under five years of age.Methods
Two transversal studies, the first one prior to the start of the IRS campaign and the second one year later. Sampling was carried out by stratified clusters. Malaria infection was measured by means of thick and thin film, and the packed cell volume (PCV) percentage. Data related to ITN use and information regarding IRS were collected. The Pearson's chi-square and logistic regression statistical tests were used to calculate odds ratios (OR)Results
In the first survey, 168 children were sampled and 433 children in the second one. The prevalence of infection was 40% in 2004, and significantly lower at 21.7% in 2005. PCV was 41% and 39%, respectively. 58% of the children surveyed in 2004 and 44.3% in 2005 had slept under an ITN. 78% of the dwellings studied in 2005 had been sprayed. In the 2005 survey, sleeping without a mosquito net meant a risk of infection 3 times greater than sleeping protected with a net hanged correctly and with no holes (p < 0.05).Conclusion
IRS and ITNs have proven to be effective control strategies on the island of Bioko. The choice of one or other strategy is, above all, a question of operational feasibility and availability of local resources. 相似文献70.
BINE XUE YVONNE C. F. SU JOHAN B. MOLS PAUL J. A. KEßLER RICHARD M. K. SAUNDERS 《分类学与生物多样性》2013,11(1):17-26
The species-rich genus Polyalthia has previously been shown to be highly polyphyletic, with species represented in at least five different clades. The Polyalthia species that are associated with Marsypopetalum and Trivalvaria (as revealed either by previous phylogenetic studies or inferred on the basis of comparative morphology) were included in a molecular phylogenetic study based on three chloroplast DNA regions (matK, rbcL and trnL-F). Maximum parsimony, maximum likelihood and Bayesian analyses consistently revealed that several Polyalthia species form a well-supported clade with Marsypopetalum pallidum, and that this clade is sister to Trivalvaria. Diagnostic morphological characters for the clades are re-evaluated and shown to be congruent with the molecular phylogeny. Five Polyalthia species (P. crassa, P. littoralis, P. lucida, P. modesta and P. tristis) are accordingly transferred to Marsypopetalum. 相似文献