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101.
We present a technique for reconstruction of the legs in patients with soft-tissue loss and formation of large scars with retraction of this tissue in the pretibial region. In such patients, a subcutaneous tissue expander is placed in the region adjacent to the scar tissue. With expansion, we obtained sufficient skin for use in the reconstruction, and the resulting asymmetry in leg diameter was compensated for by means of one or two calf prostheses, depending on the patient.  相似文献   
102.
The present study reports life-table parameters and compares the longevity, fecundity, egg-to-adult development times and the length of the reproductive periods for five phytoseiid species (Typhlodromus annectens, Amblyseius californicus, A. idaeus, Euseius concordis, andPhytoseiulus macropilis) when reared onMononychellus progresivus orTetranychus urticae. Recommendations regarding the use of these species for classical biological control ofM. tanajoa in Africa are made.  相似文献   
103.
Summary A number of structurally unrelated DNA intercalators have been studied as stabilizers of mitotic chromosomes during isolation from rodent and human metaphase cells. Seven out of the nine intercalators tested were found to be useful as chromosome stabilizing agents. Chromosome suspensions prepared in this way could be preserved for long periods of time. After isolation the chromosomal DNA was longer than 150 kb. With intercalated chromosomes high resolution flow karyotypes could be obtained as jllustrated for the non-fluorescent intercalators 9-methylene-(1,3-dimethyl-2,4-dionepyrimidine-5-yl)-phenanthridiniumchloride and 4-aminomethyl-4,5, 8-trimethylpsoralen combined with DAPI and 33258 Hoechst for fluorescent staining and for the fluorescent intercalator propidium iodide used as a stabilizer and as a fluorochrome. Passage of the intercalated chromosomes through the laser beam had no measureble effect on the length of the chromosomal DNA subsequently isolated. After flow analysis and collection on slides human chromosomes could easily be banded by Giemsa staining methods with the same resolution as obtained in conventional metaphase spreads. This allowed a ready indentification of about 80 percent of all chromosomes in the unfractionated suspension collected after passage through the laser beam.  相似文献   
104.
Based on existing literature and publicly available expression data-sets, a map of Parkinson’s disease (PD) has been inferred in collaborative effort with other teams in LCSB and Systems Biology Institute, Tokyo, Japan. However, due to the increased complexity of the map, human intuition is often insufficient in understanding the initiation, functional regulation, and progression of this disease. Hence, it is necessary to mine the information content of this network to make sense of this abundance complex information. To this end, current work aims to analyze the network topology and dynamics of the PD map, using Boolean modeling. Grounded on perturbation analysis, the work also aims to obtain a system level understanding of the genotype–phenotype relationships to identify key components in the disease regulation and to generate experimentally testable hypothesis for PD susceptibility and progression. Methodology includes using existing graph theoretical analysis tools, as well as to develop rigorous sophisticated analysis tools which could be vital for understanding the disease pathology and for successful quantitative modeling. In general, the major focus and contribution of this work aim at the fields of statistical inference, graph analysis, and dynamic modeling in systems biology.  相似文献   
105.
Two lines of investigation have highlighted the importance of antibodies to the V1/V2 domain of gp120 in providing protection from HIV-1 infection. First, the recent RV144 HIV-1 vaccine trial documented a correlation between non-neutralizing antibodies to the V2 domain and protection. Second, multiple broadly neutralizing monoclonal antibodies to the V1/V2 domain (e.g. PG9) have been isolated from rare infected individuals, termed elite neutralizers. Interestingly, the binding of both types of antibodies appears to depend on the same cluster of amino acids (positions 167–171) adjacent to the junction of the B and C strands of the four-stranded V1/V2 domain β-sheet structure. However, the broadly neutralizing mAb, PG9, additionally depends on mannose-5 glycans at positions 156 and 160 for binding. Because the gp120 vaccine immunogens used in previous HIV-1 vaccine trials were enriched for complex sialic acid-containing glycans, and lacked the high mannose structures required for the binding of PG9-like mAbs, we wondered if these immunogens could be improved by limiting glycosylation to mannose-5 glycans. Here, we describe the PG9 binding activity of monomeric gp120s from multiple strains of HIV-1 produced with mannose-5 glycans. We also describe the properties of glycopeptide scaffolds from the V1/V2 domain also expressed with mannose-5 glycans. The V1/V2 scaffold from the A244 isolate was able to bind the PG9, CH01, and CH03 mAbs with high affinity provided that the proper glycans were present. We further show that immunization with A244 V1/V2 fragments alone, or in a prime/boost regimen with gp120, enhanced the antibody response to sequences in the V1/V2 domain associated with protection in the RV144 trial.  相似文献   
106.
107.
The movements of a commercially important species, Diplodus vulgaris, were assessed in a marine-protected area to test whether their spatial and temporal activity patterns differ during and outside of their spawning season. Twelve adults were caught along the north-eastern coast of a small Mediterranean island, tagged with acoustic transmitters and released within or just outside the integral reserve. Fish detected, during both the seasons showed strong fidelity for the study area before and during the spawning season and their home range did not differ between seasons. Home ranges reached an asymptote between 12 and 174 days after release. Home range estimated by kernel utilization distributions ranged from 9,876 to 89,914 m2, with core areas of 946 to 7,274 m2. Temporal patterns frequently showed a dominant diel rhythm with most of detections occurring at daytime, independently of season. The variability in the movement patterns of D. vulgaris was lower between seasons (i.e., during and outside the spawning season) than at smaller temporal scale (i.e., between day and night) and was largely affected by inter-individual differences. Some conclusions arising from this and previous findings are useful to orient future studies on coastal fish movement and have direct implications for MPAs design.  相似文献   
108.
Little evidence of calculated reciprocity has been found in non-human primates so far. In this study, we used a simple experimental set-up to test whether partners pulled a sliding table to altruistically provide food to each other in short-term interactions. We tested 46 dyads of chimpanzees, bonobos, gorillas, orangutans, brown capuchin monkeys and spider monkeys to examine whether a subject’s tendency to provide food to a partner was directly affected by the partner’s previous behaviour, by the species, by the condition (i.e., whether the partner could access the food provided by the subject) and by the social tolerance levels within each dyad. Chimpanzees and orangutans were the only species pulling significantly more when the partner could retrieve the food altruistically provided. However, no species reciprocated food exchanges, as subjects’ probability to pull was not affected by the previous number of the partner’s pulls, with the possible exception of one orangutan dyad. Although subjects clearly knew how the apparatus worked and easily obtained food for themselves, individuals did not usually take the opportunity to provide food to their partners, suggesting that calculated reciprocity is not a common behaviour and that food exchanges are usually not reciprocated in the short-term within dyads.  相似文献   
109.
The U1 small nuclear (sn)RNA participates in splicing of pre-mRNAs by recognizing and binding to 5′ splice sites at exon/intron boundaries. U1 snRNAs associate with 5′ splice sites in the form of ribonucleoprotein particles (snRNPs) that are comprised of the U1 snRNA and 10 core components, including U1A, U1-70K, U1C and the ‘Smith antigen’, or Sm, heptamer. The U1 snRNA is highly conserved across a wide range of taxa; however, a number of reports have identified the presence of expressed U1-like snRNAs in multiple species, including humans. While numerous U1-like molecules have been shown to be expressed, it is unclear whether these variant snRNAs have the capacity to form snRNPs and participate in splicing. The purpose of the present study was to further characterize biochemically the ability of previously identified human U1-like variants to form snRNPs and bind to U1 snRNP proteins. A bioinformatics analysis provided support for the existence of multiple expressed variants. In vitro gel shift assays, competition assays, and immunoprecipitations (IPs) revealed that the variants formed high molecular weight assemblies to varying degrees and associated with core U1 snRNP proteins to a lesser extent than the canonical U1 snRNA. Together, these data suggest that the human U1 snRNA variants analyzed here are unable to efficiently bind U1 snRNP proteins. The current work provides additional biochemical insights into the ability of the variants to assemble into snRNPs.  相似文献   
110.
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