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21.
Data concerning the effectiveness of naturalistic treatments (treatment-as-usual) in child and adolescent psychiatric (CAP) services are scarce. The purpose of this prospective observational study was to examine the effectiveness of CAP treatments in a naturalistic outpatient setting. Three hundred six patients (attention-deficit/hyperactivity disorder, ADHD, n=94; conduct disorder, CD, n=57; anxiety disorder, AD, n=53; depressive disorder, DD, n=38; other diagnostic categories, n=64), from nine child and adolescent psychiatric practices in Germany, were evaluated. Treatment effects were compared between patients who received frequent treatment and patients who only participated in diagnostics and short interventions. Since randomization was not feasible, propensity score analysis methods were used. Regarding the total sample, no significant treatment effects were found. However, a subgroup analysis of the four most frequent disorders (ADHD, CD, AD, DD) showed small to moderate treatment effects in patients with ADHD and AD. In CD and DD subgroups, no significant treatment effects could be found. “Real-world” CAP outpatient treatment seems to produce significant effects for ADHD and AD, but not for CD and DD. Compared to efficacy studies, our results show that naturalistic treatment might be better than expected.  相似文献   
22.
Summary

The electrical properties of vitellogenic cockroach follicles have been studied using a two-electrode voltage-clamp technique. The resting potential of freshly isolated follicles was usually between ?30 mV and ?45 mV. A voltage-dependent inward current could be activated when the follicles were placed in a medium containing high concentrations of either Ca2+ or Ba2+. Maximal current amplitudes were 0.8μA in a medium containing 30 mM Ca2+ and 2 μA in 30 mM Ba2+. Maximal amplitudes could be elicited with depolarizing pulses to about +15 mV. The steady-state inactivation curve indicated half maximal current at a holding potential of about ?20 mV. Co2+, Ni2+ and Mn2+ inhibited the divalent cation currents in a concentration dependent manner. Half maximal inhibition was observed at about 3 mM concentration for each of the inhibitory cations.  相似文献   
23.
Abstract: Groenlandibelus rosenkrantzi from the Maastrichtian of Greenland has long been thought to constitute an early representative of spirulid coleoids. This study shows that this view must be reassessed, at least in part. A re‐investigation of the types and of material recorded subsequently has revealed that none of these specimens is conspecific with the holotype of G. rosenkrantzi. Cyrtobelus birkelundae gen. nov, sp. nov. differs from the type of G. rosenkrantzi in having lower chambers and in lacking an apically elongated sheath. The longiconic phragmocone of G. rosenkrantzi has more features in common with the presumed spirulid genus Naefia. A specimen described in detail by J. A. Jeletzky in the mid 1960s as ‘G. rosenkrantzi’ is designated holotype of C. birkelundae sp. nov., which means that internal phragmocone features are still unknown in G. rosenkrantzi. Cyrtobelus hornbyense gen. nov, sp. nov. from the Campanian of western Canada constitutes the first record of early spirulids from the northeast Pacific, being based on seventeen extraordinarily well‐preserved phragmocones. This species differs from C. birkelundae sp. nov. only in the width of the siphuncular tube. The presence of a caecum, a nacre‐less conotheca that represents the continuation of the protoconch conotheca, conothecal flaps that anchor the mural parts of the septa, and a thin investment‐like sheath are characters shared only with Recent Spirula. In particular, the unusual protoconch architecture of Cyrtobelus gen. nov. challenges a phylogenetic origin within bactritoid‐like coleoids.  相似文献   
24.
Reversed sexual dimorphism in size (RSD) occurs in most species of several taxonomic groups of birds. The hypotheses proposed to explain this phenomenon are examined theoretically, using inequalities to state selection in the most rigorous possible terms. The most pertinent empirical evidence is also examined critically. Proponents of hypotheses on the evolution of RSD have failed to consider the genetic constraints on the evolution of dimorphism. Selection for dimorphism can act on only that small portion of the genetic determination of body size that is sex limited. In general, selection for body size is much more likely to lead to a similar change (e.g. larger) in both sexes than to dimorphism. The most popular hypotheses involve selection for size-related differences in foraging ability. It is unlikely that there is variation in size-related foraging differences available for selection in a monomorphic, ancestral population. Foraging differences between the sexes cannot lead to the evolution of RSD; evolution of large and small morphs of both sexes is a more likely outcome. Selection for sex-role differentiation factors (e.g. large females lay larger eggs, small males are more agile in flight) can lead to the evolution of RSD, but only if the magnitudes of opposing selection for small males and for large females are equal. Combining selection for size-related foraging differences with selection for sex-role differentiation factors hinders the evolution of RSD until the sexes differ in size by 3 s.d . Empirical evidence supports this assertion: statistically significant differences between the sexes in the size of prey taken are found only in highly dimorphic species. The sex-role differentiation factors that have been proposed appear unlikely to provide the equal selection necessary for the evolution of RSD. Several authors have proposed that small size in males is selected for foraging ability and large size in females for some sex-role differentiation factor. Males cannot be more efficient foragers without females being less efficient and efficiency cannot be a factor only when the male is feeding his family. RSD cannot evolve in monogamous species if large females survive less well than small males. RSD might evolve as the result of sexual selection for small size in males and constraints on the reduction of size in females because of some factor associated with reproduction. Examination of seven studies indicating a relationship between female size and reproductive success shows very little unequivocal evidence for small size in females allowing breeding earlier in the season. Large size in females allows females to breed at a younger age in the sparrowhawk and pairs to form more rapidly in three species of sandpipers. Both of these may be the result of sexual selection. There are fewer theoretical problems with sexual selection as a cause for the evolution of RSD than with the other hypotheses. Empirical evidence for sexual selection is scarce but better than that for the other hypotheses. Evidence is contradictory for the selection of small size in males for agility in aerial displays for courtship or defence of territory. Large size in females does not appear to be the result of selection for competitive ability to obtain mates. Facilitation of female dominance and hence of the formation and maintenance of a pair bond is the most viable explanation of the evolution of RSD. It is most likely that all dimorphism (normal or reversed) is the result of sexual selection. RSD is correlated with birds in the diet in the Falconiformes and this is a central theme in the foraging hypotheses. This correlation may be because birds are abundant and available in a continuum of sizes, thus permitting but not causing the evolution of RSD or because species that prey upon birds are better equipped physically (and perhaps more likely behaviourally) to inflict damaging attacks on conspecifics and the greater RSD increases female dominance and the ease of pair formation.  相似文献   
25.
Four plant species (Zea mays, Lolium italicum, Phaseolus vulgaris,and Pisum sativum) were grown either with full nutrient supplyor with calcium, potassium, or nitrogen deficiency. After 4–6weeks the shoots were analysed for their content of K+, Ca2+,Mg2+, and Na+, of total anions, and of organic acids. The qualitativepattern of organic acid components, characteristic of each species,remained, with few exceptions, unchanged by deficiency treatments.Striking differences were detected in the total acid contentand in the quantities of the respective main organic acid components,especially in potassium-deficient plants. These changes showedstrong correlations with alterations of cation excess and demonstratethat aconitate in Zea mays, malonate in Phaseolus vulgaris,and citrate in Pisum sativum contribute to charge balance.  相似文献   
26.
Abstract. 1. The dispersal of the gall-forming tephritid Urophora cardui L. (Diptera: Tephritidae) and its endoparasitoid Eurytoma serratulae Latr. (Hymenoptera: Eurytomidae) from an experimental colony were investigated over a period of 4 years.
2. The dispersal rate for both fly and endoparasitoid was one to two magnitudes higher than in previous studies, which found 100 m per generation maximally. The dispersal rate of the endoparasitoid was not less than that of its host. Most newly founded colonies were small and had high extinction rates.
3. The viability of colonies of U. cardui did not correlate with the distance from the dispersal centre.
4. The dispersal rates observed are high enough to allow a multiple spread and extinction in mid-Europe in the post-pleistocene period.  相似文献   
27.
28.
1. We investigated the importance of lake water chemistry and substrate properties in regulating microbial decomposer communities on macrophyte litter. Ten lakes of differing water chemistry, including such variables as nutrient concentration, pH and dissolved organic carbon, were sampled in October 2003. Water chemistry was analysed, and litter from the macrophytes Phragmites australis, Schoenoplectus lacustris and Nuphar lutea was collected from both above and below the water surface. 2. The three plant species differed widely in carbon and nitrogen content. The aerial parts of P. australis had highest C : N ratio (mean value 125), while the lowest values were found in leaves of N. lutea (19.8). 3. Fungal carbon ranged from 0.15 to 6.4 mg g?1 dry weight (DW), and was higher on aerial than on submerged plant parts. Fungal biomass was highest on S. lacustris and lowest on N. lutea. Denaturing gradient gel electrophoresis revealed no differences in the number of fungal taxa between plant species or plant parts, with the limitation that no molecular analysis was possible for N. lutea. 4. In contrast, bacteria were most abundant on N. lutea, but showed no significant difference between leaf and stem parts. The number of bacterial taxa was highest on the submerged parts of P. australis. 5. The correlations between microbial variables and the properties of lakes and litter were analysed using multivariate statistics. In a principal component analysis, litter properties explained 78% of the variation in microbial variables. In contrast, redundancy analysis revealed that the explanatory power of lake water chemistry was only 20%, indicating that the properties of the growth substratum were more important than those of the lake water for the attached microbial communities.  相似文献   
29.
Genes of the major histocompatibility complex (MHC) encode molecules that control immune recognition and are highly polymorphic in most vertebrates. The remarkable polymorphisms at MHC loci may be maintained by selection from parasites, sexual selection, or both. If asexual species show equal (or higher) levels of polymorphisms at MHC loci as sexual ones, this would mean that sexual selection is not necessary to explain the high levels of diversity at MHC loci. In this study, we surveyed the MHC diversity of the asexual amazon molly (Poecilia formosa) and one of its sexual ancestors, the sailfin molly (P. latipinna), which lives in the same habitat. We found that the asexual molly has polymorphic MHC loci despite its clonal reproduction, yet not as polymorphic as the sexual species. Although the nucleotide diversity was similar between the asexual and sexual species, the sexual species exhibited a greater genotypic diversity compared to the asexual one from the same habitats. Within‐genome diversity was similar for MHC class I loci, but for class IIB, the sexual species had higher diversity compared to the asexual — despite the hybrid origins and higher levels of heterozygosity at microsatellite loci in the asexual species. The level of positive selection appears to be similar between the two species, which suggests that these polymorphisms are maintained by selection. Thus, our findings do not allow us to rule out the sexual selection hypothesis for the evolution of MHC diversity, and although the sexual fish has higher levels of MHC‐diversity compared to the asexual species, this may be due to differences in demography, parasites, or other factors, rather than sexual selection.  相似文献   
30.
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