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1.
The differentiation of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) poses a clinical challenge. In children, overlap of psychopathological and cognitive findings has been found for both disorders. In addition, some children suffer from both disorders. The Social Communication Questionnaire (SCQ) is a screening instrument for ASD symptoms which indicates the presence of ASD in a rapid and economic way. However, validity to differentiate ASD and ADHD as differential or comorbid diagnoses has not been studied. Here, the differential validity was compared in groups of children with ASD, ADHD, ASD + ADHD, and typically developing (TD) children and IQ > 70. ROC analyses indicated an excellent differentiation between ASD and TD with ROC–AUC = .941 and between ASD + ADHD with ROC–AUC = .993. The optimal cutoff was below the originally recommended one of 15. The differentiation between children with ASD with (ROC–AUC = .982) or without ADHD (ROC–AUC = .864) and ADHD alone also showed acceptable differential validity, and here, the optimal cutoff corresponded to the recommended. Taken together, the SCQ can be recommended as a screening instrument for a first differentiation between children with ASD and typically developing children as well as children with ADHD.  相似文献   

2.
Impairment of endothelial function forms basis for many cardiovascular diseases, therefore today it becomes an independent target for therapeutic action, and the search for new compounds possessing endothelium-protective properties is one of the prospective goals of the pharmacotherapy and medicinal chemistry. An efficient instrument to solve the problem is the use of methods of molecular modeling. Application of the methods is possible only if detailed information on three-dimensional structure and function of molecular targets—receptors and enzymes responsible for signal transduction both inside and outside endothelial cells—is available. In the review we collected the data on the structure and functions of various macromolecules involved in the process of regulation of vascular tone. The structure of endothelial NO-synthase (EC 1.14.13.39) (eNOS) responsible for synthesis of nitrogen oxide and involved in the process of vascular tone regulation is described. The importance of its substrate, L-arginine, from the point of view of eNOS activity regulation is emphasized; the data on structure and functions of L-arginine transport system are presented. Also, various pathways of eNOS activity regulation are described, including activation and competitive inhibition through binding of exogenous substances in its active center and inhibition through caveolin binding at eNOS oxygenase domain among them, as well as regulation by means of phosphorylation of individual eNOS amino acid residues by protein kinases and their dephosphorylation by phosphatases. The importance of membrane receptors of endotheliocytes as targets for substances possessing endothelium-protective activity is emphasized. Receptors of endothelin, thrombocyte activation factor, prostaglandins, bradykinin, histamine, serotonin, and protein kinase-activated receptors are among them. The importance of calcium and potassium ion channels in vessel cells for endothelium protection is emphasized. Finally, the macromolecules discussed in the review are considered as targets in the search for endothelium-protective therapeutic agents by the proposed approaches and methods of molecular modeling.  相似文献   

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With the advances of cloud computing and virtualization technologies, running MapReduce applications over clouds has been attracting more and more attention in recent years. However, as a fundamental problem, the performance of MapReduce applications can sometimes be severely degraded due to the overheads from I/O virtualization and resource competitions among virtual machines. In this paper, we propose a dynamic block device reconfiguration algorithm in virtual MapReduce clusters, which reduces the data transfer time between virtual machines and thereby improving the performance of MapReduce applications on top of the clouds. The proposed algorithm utilizes a block device reconfiguration scheme, where a block device attached to a virtual machine can be dynamically detached and reattached to other virtual machines at runtime. This scheme allows us to move files easily across different virtual machines without any network transfers between virtual machines. This algorithm is also dynamic in a sense that it estimates the total data transfer times between virtual machines using multiple regression analysis based on CPU utilization and data size, and adaptively determines a least-cost data transfer path between a mapper virtual machine and a reducer virtual machine. We have implemented our algorithm in Hadoop MapReduce. The benchmarking results showed that the overheads incurred by transferring data from mapper virtual machines to reducer virtual machines are minimized and the execution times of MapReduce applications are shortened up to 14 %.  相似文献   

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The mahseers are an important group of fishes endemic to Asia with most species considered threatened. Conservation plans to save declining wild populations are hindered by unstable taxonomy, and detailed systematic review could form a solid platform for future management and conservation. D-loop and cytochrome c oxidase I (COI) mtDNA sequences were examined in nine mahseer species of Tor, Neolissochilus, and Naziritor. Pseudogenes amplified in a portion of the species limited the utility of the D-loop region. ABGD analysis, NJ, ML, and MP methods and genetic distance (TrN?+?I?+?G) using COI data revealed concordant species delimiting patterns. The three genera were monophyletic, separated as distinct clades (TrN?+?I?+?G 0.064 to 0.106), and Naziritor was flagged as a separate genus, distinct from Puntius (TrN?+?I?+?G 0.196). Out of seven nominal species known for Tor cogeners from India, only five were recovered with mtDNA data (TrN?+?I?+?G 0.000 to 0.037) and two species could not be distinguished with the molecular data set employed. Tor mosal, synonymized as Tor putitora, was rediscovered as a distinct species (TrN?+?I?+?G 0.031) based on its type locality. Tor mussulah was confirmed as a separate species (TrN?+?I?+?G 0.019 to 0.026). Two valid species, Tor macrolepis and T. mosal mahanadicus, were not distinct from T. putitora (TrN?+?I?+?G 0.00). The high divergence with mtDNA data failed to validate T. mosal mahanadicus as a subspecies of T. mosal (TrN?+?I?+?G 0.031). Morphological outliers discovered within the distribution range of Tor tor (TrN?+?I?+?G 0.022 to 0.025) shared the same lineage with T. putitora (TrN?+?I?+?G 0.002 to 0.005), indicating a new extended distribution of the Himalayan mahseer T. putitora in the rivers of the Indian central plateau. The findings indicate the need for integrating molecular and morphological tools for taxonomic revision of the Tor and Naziritor genera, so that taxa are precisely defined for accurate in situ and ex situ conservation decisions.  相似文献   

7.
The HIV/AIDS epidemic in Haiti has often been referred to as a “mystery,” and “striking similarities” between patterns of disease in Haiti and in sub-Saharan Africa are often underlined. The occurrence of AIDS in Haitians has also led to the postulation of a number of theories positing a Haitian origin for AIDS and linking the syndrome in Haitians to voodoo. A review of the epidemiological data gathered and published in the early years of the pandemic suggests that these “exotic” theories are not necessary to explain the Haitian epidemic, which is clearly linked not to Africa but to the United States. Patterns of risk identified among many of the first Haitians with AIDS are similar to risk factors identified in North America and Europe (same-sex contact with an HIV-infected individual and blood transfusion). The Haitian epidemicsubsequently came to resemble patterns seen in sub-Saharan Africa, where AIDS is predominantly a heterosexually transmitted disease. Similarly shifting patterns are described for several other Caribbean nations, underlining the importance of a historical analysis of the Caribbean pandemic as well as the necessity to link analysis of local epidemiology of AIDS/HIV to larger considerations of political economy.  相似文献   

8.
The suitability was evaluated of MNNG as a mutagen inducing increased frequencies of mutations in the cell populations of three strains of chlorococcal algae for the purposes of selection. MNNG has proved to be highly toxic to those algae as it produces severe physiological responses of the affected cells. The mutagenic effect of MNNG was relatively small in comparison with the recorded toxic effect. From these results it has been concluded that in reverse to NEU, MNNG can hardly be applied with such good an effect in the mutation breeding of chlorococcal algae that are suitable for mass cultivation.  相似文献   

9.
Ptyas mucosus male DNA has a repetitious DNA satellite (p= 1.700 g cm?3) constituting 5% of the haploid genome. In situ hybridisation of radioactive complementary RNA (cRNA) has revealed that satellite sequences are located in the centromeric region of one pair of macrochromosomes and in the terminal region of 8 pairs of microchromosomes. These regions are constitutively heterochromatic as revealed by C-banding. The possibility of involvement of satellite rich microchromosomes in nucleolus organisation is discussed.  相似文献   

10.
Porites tissue loss is a common disease of Porites compressa on Hawaiian reefs. Despite its prevalence, to date, the aetiological agent of the disease has not been found. The apparent lack of a microbial causative agent in the similar disease Porites bleaching with tissue loss, as well as increasing evidence of viral infections in scleractinian corals and Symbiodinium, led us to hypothesise that a virus may be responsible. Electron microscopy revealed the presence of numerous and varied virus-like particles (VLPs) in healthy and diseased P. compressa colonies. While overall virus numbers were similar in all samples, the abundance of a group of icosahedral VLPs differed significantly between healthy and diseased colonies. While not conclusive, these results suggest that viruses may play a role in this disease, and provide a basis for further studies.  相似文献   

11.
Fish ribosomal RNA genes (rDNA) have been compared by restriction endonuclease digestion followed by Southern hybridization using rRNA or cloned rRNA genes as labelled probes. In several species belonging to the orders Cypriniformes and Perciformes, the simple restriction patterns revealed a high degree of size class homogeneity among the rDNA repeats and similar restriction map within a species. Different species have different restriction patterns and fragment lengths arising mostly out of different length of the nontranscribed spacer. Polymorphic restriction sites are present in some species. The species-specific differences in fragment lengths produced in rDNA by some restriction enzymes can thus be used to study interspecific fish hybrids.  相似文献   

12.
Data Grids provide environment for huge, data-intensive applications that produce and process enormous data. Such environments are thus asked to manage data and schedule jobs at the same time. These two important operations have to be tightly coupled to achieve the best results. Replication techniques are widely used to increase the availability of data, improving performance of query latency and load balancing in Data Grid. Also effective resource scheduling is a challenging research issue. In this paper we propose a job scheduling policy, called Parallel Job Scheduling (PJS), and a dynamic data replication strategy, called Threshold-based Dynamic Data Replication (TDDR), to improve the data access efficiencies in a hierarchical Data Grid. The PJS uses hierarchical scheduling to reduce the search time for an appropriate computing node. It considers network characteristics, number of jobs waiting in queue, file locations, and disk read speed of storage drive at data sources. The main idea of TDDR strategy is using a threshold value to determine if the requested replica needs to be copied to the node. The TDDR determines this threshold dynamically based on data request arrival rates and available storage capacities. Then, in order to overcome the problem of limited storage space in each node, we design an efficient replica replacement strategy, which is developed as a two stages process. First, it deletes those files with minimum time for transferring. Second, if space is still insufficient then it considers the last time the replica was requested, number of access, size of replica and file transfer time. Results from the simulation show that our proposed algorithms have better performance in comparison with other algorithms in terms of Mean Job Time, Number of Intercommunications, Number of Replications, Computing Resource Usage, and Effective Network Usage.  相似文献   

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Greater sage-grouse (Centrocercus urophasianus) within the Bi-State Management Zone (area along the border between Nevada and California) are geographically isolated on the southwestern edge of the species’ range. Previous research demonstrated that this population is genetically unique, with a high proportion of unique mitochondrial DNA (mtDNA) haplotypes and with significant differences in microsatellite allele frequencies compared to populations across the species’ range. As a result, this population was considered a distinct population segment (DPS) and was recently proposed for listing as threatened under the U.S. Endangered Species Act. A more comprehensive understanding of the boundaries of this genetically unique population (where the Bi-State population begins) and an examination of genetic structure within the Bi-State is needed to help guide effective management decisions. We collected DNA from eight sampling locales within the Bi-State (N = 181) and compared those samples to previously collected DNA from the two most proximal populations outside of the Bi-State DPS, generating mtDNA sequence data and amplifying 15 nuclear microsatellites. Both mtDNA and microsatellite analyses support the idea that the Bi-State DPS represents a genetically unique population, which has likely been separated for thousands of years. Seven mtDNA haplotypes were found exclusively in the Bi-State population and represented 73 % of individuals, while three haplotypes were shared with neighboring populations. In the microsatellite analyses both STRUCTURE and FCA separate the Bi-State from the neighboring populations. We also found genetic structure within the Bi-State as both types of data revealed differences between the northern and southern part of the Bi-State and there was evidence of isolation-by-distance. STRUCTURE revealed three subpopulations within the Bi-State consisting of the northern Pine Nut Mountains (PNa), mid Bi-State, and White Mountains (WM) following a north–south gradient. This genetic subdivision within the Bi-State is likely the result of habitat loss and fragmentation that has been exacerbated by recent human activities and the encroachment of singleleaf pinyon (Pinus monophylla) and juniper (Juniperus spp.) trees. While genetic concerns may be only one of many priorities for the conservation and management of the Bi-State greater sage-grouse, we believe that they warrant attention along with other issues (e.g., quality of sagebrush habitat, preventing future loss of habitat). Management actions that promote genetic connectivity, especially with respect to WM and PNa, may be critical to the long-term viability of the Bi-State DPS.  相似文献   

16.
The species composition of centric diatoms from Lake Frolikha (Transbaikal area) has been studied. The lake is located on the eastern shore of Lake Baikal and connected with it by a river. Twenty-three species of Centrophyceae from 7 genera (Aulacoseira, Cyclostephanos, Cyclotella, Discostella, Handmania, Pliocaenicus, and Stephanodiscus) have been found. The most represented genus is Aulacoseira (11 species). Fifteen species and 4 genera are new for the lake record. All revealed species are known in other lakes of the Baikal region; however Baikal endemics are absent in Lake Frolikha. The flora of centric diatoms in Lake Frolikha can be divided into two groups. The first group includes taxa common in Lake Baikal, and the second group includes taxa not typical for Lake Baikal. The level of differences between flora in Lake Baikal and Lake Frolikha is high (43%) despite the close location and connection to the river. An analysis of distribution of interesting species in Asia is presented.  相似文献   

17.
Complexes of water soluble proteins (albumins) were investigated in three cultivarsof Phaseolus vulgaris, viz: Yeltruská Saxa, Vainica Saavegra B, and Krupnaya sakharnaya. The first two cultivars exhibit haemagglutinating activity against rabbit erythrocytes, but have different elution profiles on Sephadex G-100. Their individual peaks have a different subunit composition, as revealed by SDS gel electrophoresis, as well as a different immunoelectrophoretic pattern, although proteins I and II of the specificity Veltruská Saxa are present in both cultivars. The cultivar Krupnaya sakharnaya expressively differs from the preceding lectin cultivars; it has no erythroagglutinating activity, its albumin complex has a high-molecular component, absent in the preceding ones, and has no lectin peak in the region of molecular mass of 100 000 to 200 000. Immunoelectrophoresis gave no evidence of protein I and II of the specificity Veltruská Saxa.  相似文献   

18.
Computerization of the Edward Lee Greene Herbarium at Notre Dame is described. Reasons for the justification of such a project and the steps involved in data accumulation and data processing are presented. Results are or will be available in two forms: 1) formal publications containing summary information, including information on the more than 4400 taxa that Greene named; and 2) a computerized data bank that today can provide answers to questions from individual systematists about the 65,000 specimens. Problems in automation are discussed, as are the relation of this project to similar ones. Finally, an invitation is extended to readers to query the data bank without cost.  相似文献   

19.
The cAMP-dependent signaling cascades play the key role in regulation of fertility of spermatozoa. Synthesis of cAMP in spermatozoa is realized both by soluble, and by transmembrane (membrane-bound) forms of adenylyl cyclases (AC). For the recent years numerous data appeared about the presence in spermatozoa at different stages of their maturation of a wide spectrum isoforms of membrane-bound AC and their regulation by hormones and hormone-like substances via the coupled to B-proteins receptors (GPCR). Agonists of GPCR in spermatozoa can be adenosine, biogenic amines, peptide hormones, odorants. Study of structural-functional organization and regulatory properties of AC of the signal system in spermatozoa is of great practical significance for reproductive technologies, as via the membrane-bound AC forms and signal cascades there are controlled such processes as motility and chemotaxis of spermatozoa, their capability for capacitation acrosomal reaction. In the review there are summarized and analyzed data on functioning and role of AC of signal system in spermatozoa of human and vertebrate animals and are discussed achievements and unsolved problems in this field.  相似文献   

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