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81.
STEIN WH 《The Journal of biological chemistry》1953,201(1):45-58
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83.
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
84.
High external concentrations of potassium were found to promote light-induced growth of cucumber cotyledons similarly to the effects previously observed for the growth induced by cytokinins. At 40 mM KCl, the response to white light was 3.6 times greater than in the absence of KCl. The promotive effect of calcium on the growth induced by cytokinin was not observed for light. In 40 mM KCl and 10 mM CaCl2, the responses to light and cytokinin were similar and additive. Both near-red and far-red light induced growth at low intensities. The response to white light at low intensities was sharply increased with higher intensity up to 24 μE m-2 s-1 and only slightly increased above that level. Abscisic acid was found to inhibit strongly the responses to light and cytokinin. The inhibition was greater in the presence of KCl than in its absence and thus abscisic acid appeared to inhibit primarily by its interference with potassium uptake. Kinetic analysis found the light response promoted by potassium to be inhibited competitively by abscisic acid, with the light response having a Km of 34 mM KCl and a Vmax of 115 mg/cotyledon × 4 days. The inhibition of the cytokinin response by abscisic acid was noncompetitive in relation to potassium, having a Km of 1 mM KCl and a Vmax of 50 mg/cotyledon × 4 days. It is suggested that cytokinin, light and abscisic acid have primary properties affecting membrane permeability and that their interaction with potassium is an explanation of many similarities between light and cytokinin responses and their inhibition by abscisic acid. 相似文献
85.
The polymerase chain reaction (PCR) method readily detected bean yellow mosaic virus (BYMV) in gladioli leaves, but in initial tests PCR did not detect virus in corm tissue. Extracts of RN A from corm tissue were shown to inhibit the amplification of viral sequences when added to a PCR reaction. An additional purification step for the RNA extracts using a Sephadex G-50 column eliminated the inhibitory effect and enabled PCR to amplify and detect viral RNA in corm tissue preparations. 相似文献
86.
The effect of fire on the distribution of large wild herbivores during the late dry season was studied in northern Tanzania during October 1987. All species were attracted to burnt-over areas with 1–10 cm regrowth of grass. Recently burnt areas with no regrowth and areas not burnt during the dry season were avoided.
By the end of the dry season the study area was left as a fire mosaic, with different areas burnt at different times during the dry season. Thirty two percent was unburnt. The fires were mainly man-made but for purposes other than wildlife management. Such a fire mosaic has a positive effect on the larger herbivores by supplying protein-rich food during the dry season.
On a étudié en octobre 1987, durant la deuxième saison sèche l'effet du feu sur la distribution de grands herbivores dans le nord de la Tanzanie.
Toutes les espèces sont attirées par les surfaces brûlées où les repousses sont de 1 à 10 cm. Les surfaces sans repousses et les zones non brúéees sont évitées. A la fin de la saison sèche, la zone étudiée ressemblait à une mosaïque due au feu, avec des endroits brûlés a des moments différents durant la saison sèche. Trente-deux pour-cents n'avaient pas brûlé. La plupart des feux avaient été allumes par l'homme, mais dans d'autres buts que la gestion de la faune. Une telle mosaïque a un effet positif sur les grands herbivores car elle fournit un complément de nourriture riche en protéines au cours de la saison sèche. 相似文献
By the end of the dry season the study area was left as a fire mosaic, with different areas burnt at different times during the dry season. Thirty two percent was unburnt. The fires were mainly man-made but for purposes other than wildlife management. Such a fire mosaic has a positive effect on the larger herbivores by supplying protein-rich food during the dry season.
Résumé
On a étudié en octobre 1987, durant la deuxième saison sèche l'effet du feu sur la distribution de grands herbivores dans le nord de la Tanzanie.
Toutes les espèces sont attirées par les surfaces brûlées où les repousses sont de 1 à 10 cm. Les surfaces sans repousses et les zones non brúéees sont évitées. A la fin de la saison sèche, la zone étudiée ressemblait à une mosaïque due au feu, avec des endroits brûlés a des moments différents durant la saison sèche. Trente-deux pour-cents n'avaient pas brûlé. La plupart des feux avaient été allumes par l'homme, mais dans d'autres buts que la gestion de la faune. Une telle mosaïque a un effet positif sur les grands herbivores car elle fournit un complément de nourriture riche en protéines au cours de la saison sèche. 相似文献
87.
Predicting impact of freshwater exotic species on native biodiversity: Challenges in spatial scaling
DAVID M. LODGE ROY A. STEIN KENNETH M. BROWN ALAN P. COVICH CHRISTER BR
NMARK JAMES E. GARVEY STEVEN P. KLOSIEWSKT 《Austral ecology》1998,23(1):53-67
Abstract Global homogenization of biota is underway through worldwide introduction and establishment of nonindigenous (exotic) species. Freshwater ecologists should devote more attention to exotic species for two reasons. First, exotics provide an opportunity to test hypotheses about what characteristics of species or habitats are related to successful establishment or invasibility, respectively. Second, predicting which species will cause large ecological change is an important challenge for natural resource managers. Rigorous statistical relationships linking species characteristics to probability of establishment or of causing ecological impacts are needed. In addition, it is important to know how reliable different sorts of experiments are in guiding predictions. We address this issue with different spatial scales of experiments testing the impact of two predators on native snail assemblages in northern Wisconsin USA lakes: an exotic crayfish, the rusty crayfish (Orconectes rusticus); and a native fish predator, the pumpkinseed sunfish (Lepomis gibossus). For the crayfish, laboratory experiments, a field cage experiment, and a snapshot survey of 21 lakes gave consistent results: the crayfish reduced abundance and species richness of native snails. Laboratory and field experiments suggested that pumpkinseed sunfish should have a similar impact, but the lake survey suggested little impact. Unfortunately, no algorithms exist to guide scaling up from small-scale experiments to the whole-lake, long-term management scale. To protect native biodiversity, management of freshwater exotic species should be targeted on lakes or drainages that are both vulnerable to colonization by an exotic, and that harbour endemic species. Management should focus on preventing introduction because eradication after establishment is usually not possible. 相似文献
88.
SYBILLE B. UNSICKER GÜNTER KÖHLER JEANINE LINZ CLAUDIA STEIN WOLFGANG W. WEISSER 《Ecological Entomology》2008,33(5):631-637
Abstract 1. Polymorphism has been described for a number of herbivorous insects, but little is known about whether differences in body colour cause fitness differences. In Chorthippus parallelus, three main colour morphs occur, namely brown, green, and dorsally striped. 2. The present study examined colour morph abundances and morph‐related differences in body size, oviposition rate, and offspring numbers in females of C. parallelus collected in 15 montane grasslands. The study also examined the effect of plant species richness, composition, community productivity, and solar radiation on colour morph frequency and fitness. 3. The relative frequencies of the three colour morphs was 31.7% (brown), 33.1% (green), and 35.2% (dorsally striped), but the morphs were not evenly distributed across the 15 sites. 4. There was no effect of the habitat variables on the distribution of the green and the striped morph in the study sites, however 80% of the variation in the abundances of the brown morph was explained by plant species richness and composition. 5. Grasshopper size was equal among the morphs. Brown females laid significantly more egg pods than the green and dorsally striped morphs. There were no significant differences in offspring numbers among the colour morphs. 6. Body colour in C. parallelus seems to be a fitness‐relevant trait, raising the question of the evolutionary maintenance of polymorphism. 相似文献
89.
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