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81.
RONALD C KESSLER MATTHIAS ANGERMEYER JAMES C ANTHONY RON DE GRAAF KOEN DEMYTTENAERE ISABELLE GASQUET GIOVANNI DE GIROLAMO SEMYON GLUZMAN OYE GUREJE JOSEP MARIA HARO NORITO KAWAKAMI AIMEE KARAM DAPHNA LEVINSON MARIA ELENA MEDINA MORA MARK A OAKLEY BROWNE JOSé POSADA-VILLA DAN J STEIN CHEUK HIM ADLEY TSANG SERGIO AGUILAR-GAXIOLA JORDI ALONSO SING LEE STEVEN HEERINGA BETH-ELLEN PENNELL PATRICIA BERGLUND MICHAEL J GRUBER MARIA PETUKHOVA SOMNATH CHATTERJI T. BEDIRHAN üSTüN 《World psychiatry》2007,6(3):168-176
Data are presented on the lifetime prevalence, projected lifetime risk,
and age-of-onset distributions of mental disorders in the World Health Organization
(WHO)''s World Mental Health (WMH) Surveys. Face-to-face community surveys
were conducted in seventeen countries in Africa, Asia, the Americas, Europe,
and the Middle East. The combined numbers of respondents were 85,052. Lifetime
prevalence, projected lifetime risk, and age of onset of DSM-IV disorders
were assessed with the WHO Composite International Diagnostic Interview (CIDI),
a fully-structured lay administered diagnostic interview. Survival analysis
was used to estimate lifetime risk. Median and inter-quartile range (IQR)
of age of onset is very early for some anxiety disorders (7-14, IQR: 8-11)
and impulse control disorders (7-15, IQR: 11-12). The age-of-onset distribution
is later for mood disorders (29-43, IQR: 35-40), other anxiety disorders (24-50,
IQR: 31-41), and substance use disorders (18-29, IQR: 21-26). Median and IQR
lifetime prevalence estimates are: anxiety disorders 4.8-31.0% (IQR: 9.9-16.7%),
mood disorders 3.3-21.4% (IQR: 9.8-15.8%), impulse control disorders 0.3-25.0%
(IQR: 3.1-5.7%), substance use disorders 1.3-15.0% (IQR: 4.8-9.6%), and any
disorder 12.0-47.4% (IQR: 18.1-36.1%). Projected lifetime risk is proportionally
between 17% and 69% higher than estimated lifetime prevalence (IQR: 28-44%),
with the highest ratios in countries exposed to sectarian violence (Israel,
Nigeria, and South Africa), and a general tendency for projected risk to be
highest in recent cohorts in all countries. These results document clearly
that mental disorders are commonly occurring. As many mental disorders begin
in childhood or adolescents, interventions aimed at early detection and treatment
might help reduce the persistence or severity of primary disorders and prevent
the subsequent onset of secondary disorders. 相似文献
82.
ALBERTO SANTINI VITTORIO LUCCHINI ELENA FABBRI ETTORE RANDI 《Molecular ecology resources》2007,7(6):955-961
Individual genotypes determined from noninvasive DNA samples (typically extracted from shed hairs or scats) are used to estimate population size in monitoring projects of elusive species. However, polymerase chain reaction (PCR) success rates usually are lower, and genotyping errors higher than in standard population genetic surveys, due to DNA degradation or contamination in aged field samples. In this study, we evaluate the results of common garden experiments showing that DNA degradation is significant in wolf (Canis lupus) scats older than 3 days, and it is enhanced in scats in direct contact with soil. A storage test showed that samples kept frozen in 95% ethanol performed better compared to other methods. However, variance of PCR success among samples was high, independent on sample age or storage condition. The detrimental consequences of DNA degradation can be avoided by collecting scat samples as fresh as possible, and implementing efficient multitube procedures and stringent quality control of the laboratory results. Efficient multitube procedures can produce reliable data, like in this study, which showed that the consensus genotypes obtained from excremental DNA exactly matched distinct reference genotypes obtained from wolf blood samples. 相似文献
83.
BRUNO FOGGI M. ELENA GHERARDI M. ADELE SIGNORINI GRAZIANO ROSSI PIERO BRUSCHI 《Botanical journal of the Linnean Society. Linnean Society of London》2006,151(2):239-258
According to current systematics, Festuca inops and F. gracilior are two distinct species. However, they are hardly distinguishable from each other on the basis of their morphological characters. Festuca inops is considered a diploid species endemic to Italy, while F. gracilior has a discontinuous distribution area, apparently related to chromosomal levels: diploid populations in Italy and south-east France, tetraploid populations in north-east Spain. The diploid populations of both taxa from Italy and south-east France are investigated in the present study. Nearly 1000 exsiccata were examined and morphometric analysis was carried out on macro- and micromorphological features of 119 specimens (including type-specimens) and on 20 natural populations (including loci classici ). All these data showed that the two species should be referred to a single taxon, for which the rank of species seems to be appropriate. This result is supported by karyological, ecological and chorological data and was confirmed by the results of ISSR analysis. According to nomenclatural rules, the legitimate name for the species is Festuca inops De Not. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 239–258. 相似文献
84.
CHIARA ATZORI FIORENZA AGOSTONI ELENA ANGELI GIOVANNA ORLANDO ANTONIETTA CARGNEL 《The Journal of eukaryotic microbiology》1996,43(5):42S-42S
SUMMARY Pneumocystis carinii pneumonia (PCP) is usually diagnosed by examination of BAL, a sample often unpleasant to be collected from immunocompromised host affected by acute respiratory disease. We studied by the Internal Transcribed Spacers (ITSs) nested PCR the presence of P. carinii DNA in serum and Peripheral Blood Mononuclear Cells (PBMC) during acute episodes of PCP to test blood as a possible noninvasive diagnostic tool. 相似文献
85.
86.
ELENA VALSECCHI DEBBIE GLOCKNER-FERRARI MARK FERRARI & WILLIAM AMOS 《Molecular ecology》1998,7(10):1419-1422
Sloughed whale skin contains enough DNA for genetic analysis, and offers a nonintrusive method for collecting tissue. Here, we examine the efficiency of sloughed skin sampling using 1460 samples collected from free-ranging humpback whales. Samples were sexed and screened for up to 10 microsatellite markers. The vast majority of samples appear genetically compatible with field observations. About 1% of groups revealed more genotypes than whales, but we argue that this is more likely to be due to unobserved whales than to contamination. Sloughed skin sampling is particularly effective when applied to active groups and offers a viable alternative to biopsy darting in regions where darting is either not permitted or otherwise undesirable. 相似文献
87.
MARÍA ELENA FERNÁNDEZ ALDO IVÁN VASSALLO MARCELO ZÁRATE 《Biological journal of the Linnean Society. Linnean Society of London》2000,71(1):71-90
The Pliocene caviomorph rodent Actenomys has long been recognized as an early fossorial representative of the subfamily Ctenomyinae (Octodontidae), which includes one living genus, Ctenomys (tuco-tucos), and several species widely distributed in South America. To assess the de gree of specialization for digging in Actenomys , we performed morphological comparisons with other octodontid genera (Octodon, Spalacopus , and Ctenomys) of known mode of life and behaviour. As a whole, our results indicate that, in terms of morphological specializations for digging, Actenomys occupies an intermediate position between Octodon , a generalized semi-fossorial rodent which forages above ground, and Ctenomys-Spalacopus , two highly specialized subterranean forms. The position of the deltoid process (humerus) and the length of the olecranon process (ulna)–two traits which affect the out-forces exerted by several forelimb muscles–were in Actenomys intermediate between non-subterranean and subterranean taxa. The skull, particularly the rostrum, appears to be strong, and sagittal and nuchal crests are well marked. The zygomatic arches arc as flared as those of the generalized Octodon. Notably, the upper and lower incisors of Actenomys were extremely procumbent, as in many highly-specialized chisel-tooth digging species. Based upon the stratigraphic and sedimentological analysis of the palaeosoils containing its fossil remains, we suggest that Actenomys lived in an environment of moderate to hig primary productivity. The texture of the palaeosoils indicate that theywere hard and highly cohesive. This situation, which contrasts with that observed in living Ctenomyinae, has relevant implications for burrowing cost. The integration of morphological and palaeoenvironmental data allowed testing of hypotheses about the palaeobiological attributes of this ancestral ctenomyine. 相似文献
88.
JACQUES L. DAVID ELENA BENAVENTE CÉCILE BRÈS-PATRY JEAN-CLAUDE DUSAUTOIR MERCEDES ECHAIDE 《Biological journal of the Linnean Society. Linnean Society of London》2004,82(4):503-510
Spontaneous hybridization between durum wheat ( Triticum turgidum durum ) and Aegilops ovata is regularly observed in nature. The frequency of spontaneous amphiploidy in sympatric populations was estimated at 10−6 (direct in situ observations and germinated seed collected from A. ovata plants). In nursery conditions some genotype combinations gave frequencies that were much higher at 10−3 . Genomic in situ hybridization revealed that fertile amphiploids had arisen through unreduced gametes, and that some of them carried wheat − A. ovata recombinant chromosomes. The frequency of production of unreduced gametes is probably genetically inherited. Amphiploids provide a route for gene flow, including that of transgenes, to the wild. Gene flow could potentially be minimized through the choice of wheat cultivars that produce a low frequency of unreduced gametes. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 82 , 503–510. 相似文献
89.
ELENA IVARS‐MARTÍNEZ GIUSEPPE D’AURIA FRANCISCO RODRÍGUEZ‐VALERA CRISTINA SÁNCHEZ‐PORRO ANTONIO VENTOSA IAN JOINT MARTIN MÜHLING 《Molecular ecology》2008,17(18):4092-4106
Twenty‐three isolates of the widely distributed marine bacteria Alteromonas macleodii have been analysed by multilocus sequence analysis combined with phylogenetic and multivariate statistical analyses. The strains originated from the Pacific Ocean, Mediterranean Sea, English Channel, Black Sea and Thailand. Using the nucleotide sequences of nine loci for each of the 23 isolates, a robust identification was achieved of different clades within the single species. Strains generally clustered with the depth in the water column from which the isolate originated. Strains also showed more recombination with isolates from the same vicinity, suggesting that genetic exchange plays a role in diversification of planktonic marine prokaryotes. This study thus shows for the first time for a large set of isolates of a species of planktonic marine prokaryotes that multilocus sequence analysis overcomes the problems associated with the analysis of individual marker genes or presence of extensive recombination events. It can thus achieve intraspecific identification to the level of genotypes and, by comparison with relevant environmental data, ecotypes. 相似文献
90.
ARISTEIDIS PARMAKELIS ELENA KLOSSA‐KILIA GEORGE KILIAS KOSTAS A. TRIANTIS SPYROS SFENTHOURAKIS 《Biological journal of the Linnean Society. Linnean Society of London》2008,95(2):361-370
In the present study, we employed three mitochondrial DNA genetic markers in a phylogenetic analysis aiming at the delineation of the relationships amongst nominal Trachelipus kytherensis populations, as well as between populations of this species and of Trachelipus aegaeus and a new form, occurring syntopically with the latter. Both the phylogenetic analysis and the genetic distances separating populations, show the presence of several distinct and well differentiated clades that undermine the monophyly of T. kytherensis. On the other hand, despite the insular distribution of T. aegaeus populations, their divergence is low and the monophyly of this taxon can be rescued by the inclusion of two more insular populations previously assigned to T. kytherensis. The patterns of genetic divergence among clades are only partially congruent with the geographic distribution of populations. The validity of taxonomic characters used so far in the genus appears to be questionable; therefore, a more comprehensive phylogenetic study at a population level is deemed necessary for understanding the divergence of Trachelipus lineages. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 95 , 361–370. 相似文献