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The gene transfer agent (GTA) is a phage-like particle capable of exchanging double-stranded DNA fragments between cells of the photosynthetic bacterium Rhodobacter capsulatus. Here we show that the major capsid protein of GTA, expressed in E. coli, can be assembled into prohead-like structures in the presence of calcium ions in vitro. Transmission electron microscopy (TEM) of uranyl acetate staining material and thin sections of glutaraldehyde-fixed material demonstrates that these associates have spherical structures with diameters in the range of 27-35 nm. The analysis of scanning TEM images revealed particles of mass approximately 4.3 MDa, representing 101+/-11 copies of the monomeric subunit. The establishment of this simple and rapid method to form prohead-like particles permits the GTA system to be used for genome manipulation within the photosynthetic bacterium, for specific targeted drug delivery, and for the construction of biologically based distributed autonomous sensors for environmental monitoring.  相似文献   
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Previously we reported on strong linkage disequilibrium (LD) between the mono-S-C4B-RCCX module (mono-S) and the TNF2 allele (both known constituents of the 8.1 ancestral haplotype (8.1 AH)) in two Caucasian populations. The gene for the receptor of advanced glycation endproducts (RAGE) is encoded between the RCCX module and the HLA class II genes in the central MHC region. In order to assess the relationship between the promoter polymorphisms of the RAGE gene and the 8.1 AH, we performed a family study in eight informative families affected with type 1 diabetes mellitus; haplotypes of a RAGE promoter SNP (-429T>C) with the HLA-DQ2, -DR-3(17) and TNF2 alleles, as well as the mono-S genotype were determined. A similar analysis was performed in 82 unrelated patients with type 1 diabetes mellitus, and in unrelated healthy individuals of three different Caucasian populations (Hungarians, Ohioian females, Icelandics). In the diabetic patients clinical correlations were also investigated. Out of the 32 paternal and maternal chromosome 6 from the eight families, 15 different MHC haplotypes were found. Haplotypes containing at least three of the known constituents of the 8.1 AH (HLA-DQ2, -DR17, mono-S, TNF2) were always linked to the RAGE -429C allele. The RAGE -429C allele exhibited highly significant (p<0.0001) LD coefficients to known constituents of the 8.1 AH both in healthy persons and patients with type 1 diabetes. In the group of patients with diabetes we found significantly (p=0.013) higher maximal hemoglobinA1C concentration in the carriers of the RAGE -429C allele, this trait, however was not linked to the 8.1 AH. Our present findings indicate that the RAGE -429C allele can be considered as a candidate member of the 8.1 AH. The results also reveal a spectrum of recombinant MHC haplotypes in addition to the conserved ancestral haplotypes.  相似文献   
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This article describes a twinning relationship between the Canadian Association of Midwives (CAM) and the Tanzania Midwives Association (TAMA). It argues that the twinning relationship strengthened both associations. The article briefly reviews the existing literature on professional associations and association strengthening to demonstrate that professional associations are a vital tool for improving the performance of healthcare workers and increasing their capacity to contribute to national and international policy-making. It then suggests that midwifery associations are particularly significant given the frequent professional marginalization of midwives. The article then describes in depth the relationship between CAM and TAMA, highlighting the accomplishments of the twinned partners, and analyzing the factors that contributed to the success of the relationship. The findings demonstrate that twinning can successfully strengthen associations, increasing their ability to support their membership, care for the public, and shape national policy-making. The article therefore proposes twinning as a successful and cost-effective model for encouraging the growth of the midwifery profession.  相似文献   
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Background

Venous thromboembolism (VTE) is common in cancer patients and its treatment is associated with a high risk of recurrent VTE (rVTE) and bleeding.

Objectives

To analyze data from the Comparison of Acute Treatments in Cancer Hemostasis (CATCH) trial to describe the impact of rVTE and bleeding events on health-related quality of life.

Methods

The three-level EuroQol five-dimensional questionnaire (EQ-5D) data were collected monthly for up to 7 months in patients starting anticoagulation for newly diagnosed VTE. Analyses were designed to describe the impact of rVTE and bleeding on EQ-5D scores while controlling for effects of covariates such as background and clinical variables and longitudinal changes. A repeated-measures model with specification of the variance-covariance matrix to characterize the intrapatient correlation was used to estimate the utility values. The impact of an rVTE or a bleeding event was assumed to be reflected in the utility value when it occurred within 2 weeks from a planned data collection point.

Results

Data were available from 883 patients. A total of 76 rVTE and 159 bleeding events occurred during follow-up. rVTE had a significant impact on EQ-5D scores, with a decrement of ?0.075 on the basis of our reference case (male, no metastasis, Eastern Cooperative Oncology Group score = 1, Western European), but different patients might have different decrements. Bleeding events had a smaller (nonstatistically significant) impact on EQ-5D scores.

Conclusions

This data set study has quantified the decline in EQ-5D scores associated with experiencing rVTE or bleeding events in cancer patients. These results indicate the net gain in quality of life and impact on cost-effectiveness of secondary VTE prevention.  相似文献   
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Manuelle Medizin - Die Indikation zum prothetischen Ersatz der oberen Extremität wurde in den letzten Jahren von der klassischen Amputation auch auf Patienten mit Verlust oder angeborenen...  相似文献   
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