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1.
This is the first record of seed transmission of turnip yellow mosaic virus (TYMV) in oilseed and turnip rapes. The seed transmission of TYMV in a naturally infected winter turnip rape (Brassica napus var. silvestris) cultivar Perko PVH was investigated. By ELISA 1.6%, 3.2% and 8.3% seed transmission of the virus was found in seed of plants from three localities. The proportion of infected seeds produced by artificially infected plants of winter oilseed rape (Brassica napus ssp. oleifera) and winter turnip rape cultivars was determined. The virus transmission rate, expressed as the proportion of virus-infected plants which germinated from the seed was for the oilseed rape cvs Jet Neuf 0.1%, Solida 0.4%, Silesia 0.8%, Darmor 1.2%, SL-507 0.2%, SL-509 0.0% and for the winter turnip rape cv. Perko 1.5%. ELISA cannot be used in direct tests on bulk seed lots to estimate proportion of infected seed, but must be used on germinated seedlings.  相似文献   
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Supraorbital bones in Saurolophus angustirostris are described, and their presence in all hadrosaurs is suggested. Frontal-nasal and premaxillar-nasal fontanellae are distinguished in hadrosaurs; their presence is explained as connected with growth and considered to he responsible for the variability of crest structures. New data indicating the presence of a cartilaginous diverticulum nasi within the circumnarial depression in Saurobphus ongustirostris are presented. A physiological (respiratory and/or thermoregulatory) function of the nasal diverticulum is proposed.  相似文献   
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The paper presents multiplex panels of polymorphic microsatellites for two closely related cryptic species Pipistrellus pipistrellus and Pipistrellus pygmaeus. We tested the cross‐species amplification of 34 microsatellite loci, originally developed for five vespertilionid bat species. Ten and nine polymorphic loci in P. pipistrellus (mean number of alleles per locus = 10.5) and P. pygmaeus (8.1), respectively, in three multiplex polymerase chain reactions per species were amplified. All loci can be analysed in a single fragment analysis and can be used as markers to the study of evolution and the ecology of structured populations of socially living bats.  相似文献   
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Background  

Cystic Fibrosis is a pleiotropic disease in humans with primary morbidity and mortality associated with a lung disease phenotype. However, knockout in the mouse of cftr, the gene whose mutant alleles are responsible for cystic fibrosis, has previously failed to produce a readily, quantifiable lung phenotype.  相似文献   
9.

Background

Serum anti-Mullerian hormone (AMH) is currently considered the best marker of ovarian reserve and of ovarian responsiveness to gonadotropins in in-vitro fertilization (IVF). AMH assay, however, is not available in all IVF Units and is quite expensive, a reason that limits its use in developing countries. The aim of this study is to assess whether the "ovarian sensitivity index" precisely reflects AMH so that this index may be used as a surrogate for AMH in prediction of ovarian response during an IVF cycle.

Methods

AMH serum levels were measured in 61 patients undergoing IVF with a "long" stimulation protocol including the GnRH agonist buserelin and recombinant follicle-stimulating hormone (rFSH). Patients were divided into four subgroups according to the percentile of serum AMH and their ovarian stimulation was prospectively followed. Ovarian sensitivity index (OSI) was calculated dividing the total administered FSH dose by the number of retrieved oocytes.

Results

AMH and OSI show a highly significant negative correlation (r = -0.67; p = 0.0001) that is stronger than the one between AMH and the total number of retrieved oocytes and than the one between AMH and the total FSH dose.

Conclusions

OSI reflects quite satisfactory the AMH level and may be proposed as a surrogate of AMH assay in predicting ovarian responsiveness to FSH in IVF. Being very easy to calculate and costless, its use could be proposed where AMH measurement is not available or in developing countries where limiting costs is of primary importance.  相似文献   
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A common characteristic of the central nervous system (CNS) neurodegenerative disorders is neuroinflammation, marked by augmented numbers of activated and primed microglia, increased inflammatory cytokines and decreased anti-inflammatory molecules. CNS neuroinflammation is a critical component in the progression of several neurodegenerative diseases which sensitize the brain to produce an exaggerated response to immune stimuli in the periphery. Neuroinflammation might initiate from the periphery and peripheral conditions through disrupted blood-brain barrier powerfully influence various brain pathologies. Gastrointestinal tract (GIT) represents a vulnerable area through which pathogens influence the brain and induce CNS neuroinflammation. The pathogens may access the CNS through blood, the nasal olfactory pathways and the GIT. Potential GI pathogens, such as Helicobacter pylori, induce humoral and cellular immune responses that, owing to the sharing of homologous epitopes (molecular mimicry), cross-react with CNS components thereby contributing and possibly perpetuating neural tissue damage. GIT is strictly connected to the CNS and a bi-directional communication exists between them. The brain is involved in regulating the immune and gut system. Conversely, limited attention has been paid on the GIT role in the development and regulation of the CNS autoimmune diseases. The GIT is the primary immune organ with specialized immunoregulatory and anti-inflammatory functions, represented by the gastrointestinal immune system (GIS). This review focuses on the potential GIS and brain dialogue implicated in neurodegenerative diseases. Gaining a better understanding of the relationship between GIS and CNS could provide an insight on the pathogenesis and therapeutic strategies of these disorders.  相似文献   
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