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51.
Abstract The region of the chromosome immediately upstream of the Escherichia coli gene gcpE has been cloned and sequenced. This region contains two functional open reading frames, orf 384 and orf 337, encoding proteins of 43082 and 36189 Da, respectively. Sequencing analysis (this paper) and the isolation of a DNA fragment containing a functional promoter (Talukder, A.A., Yanai, S., and Yamada, M. (1994) Biosci. Biotech. Biochem. 58, 117–120) indicate that orf 337 is in an operon with gcpE . The gene orf 384 is immediately downstream of the gene ndk , which encodes nucleoside diphosphate kinase.  相似文献   
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53.

Background:

Understanding the health care experience of people with dementia and their caregivers is becoming increasingly important given the growing number of affected individuals. We conducted a systematic review of qualitative studies that examined aspects of the health care experience of people with dementia and their caregivers to better understand ways to improve care for this population.

Methods:

We searched the electronic databases MEDLINE, Embase, PsychINFO and CINAHL to identify relevant articles. We extracted key study characteristics and methods from the included studies. We also extracted direct quotes from the primary studies, along with the interpretations provided by authors of the studies. We used meta-ethnography to synthesize the extracted information into an overall framework. We evaluated the quality of the primary studies using the Consolidated Criteria for Reporting Qualitative Research (COREQ) checklist.

Results:

In total, 46 studies met our inclusion criteria; these involved 1866 people with dementia and their caregivers. We identified 5 major themes: seeking a diagnosis; accessing supports and services; addressing information needs; disease management; and communication and attitudes of health care providers. We conceptualized the health care experience as progressing through phases of seeking understanding and information, identifying the problem, role transitions following diagnosis and living with change.

Interpretation:

The health care experience of people with dementia and their caregivers is a complex and dynamic process, which could be improved for many people. Understanding these experiences provides insight into potential gaps in existing health services. Modifying existing services or implementing new models of care to address these gaps may lead to improved outcomes for people with dementia and their caregivers.The global prevalence of Alzheimer disease and related dementias is estimated to be 36 million people and is expected to double in the next 20 years.1 Several recent strategies for providing care to patients with dementia have highlighted the importance of coordinated health care services for this growing population.25 Gaps in the quality of care for people with dementia have been identified,68 and improving their quality of care and health care experience has been identified as a priority area.25Incorporating the health care experience of patients and caregivers in health service planning is important to ensure that their needs are met and that person-centred care is provided.9 The health care experience of people with dementia and their caregivers provides valuable information about preferences for services and service delivery.10 Matching available services to patient treatment preferences leads to improved patient outcomes11,12 and satisfaction without increasing costs.13 Qualitative research is ideally suited to exploring the experiences and perspectives of patients and caregivers and has been used to examine these experiences for other conditions.14 We performed a systematic review and meta-ethnographic synthesis of qualitative studies exploring the health care experience of people with dementia and their caregivers in primary care settings, and we propose a conceptual framework for understanding and improving these health care experiences.  相似文献   
54.
In many groups of organisms, especially in the older literature, it has been common practice to recognize sympatrically occurring phenotypic variants of a species as “forms”. However, what these forms really represent often remains unclear, especially in poorly studied groups. With new algorithms for DNA‐based species delimitation, the status of forms can be explicitly tested with molecular data. In this study, we test a number of what is now recognized as valid species of water mites (Hydrachnidia), but have in the past been treated as forms sympatrically occurring with their nominate species. We also test a form without prior taxonomical status, using DNA and morphometrics. The barcoding fragment of COI, nuclear 28S and quantitative analyses of morphological data were used to test whether these taxa merit species status, as suggested by several taxonomists. Our results confirm valid species. Genetic distances between the form and nominate species (Piona dispersa and Piona variabilis, COI 11%), as well as likelihood ratio tests under the general mixed‐Yule coalescent model, supported that these are separately evolving lineages as defined by the unified species concept. In addition, they can be diagnosed with morphological characters. The study also reveals that some taxa genetically represent more than one species. We propose that P. dispersa are recognized as valid taxa at the species level. Unionicola minor (which may consist of several species), Piona stjordalensis, P. imminuta s. lat., and P. rotundoides are confirmed as species using this model. The results also imply that future studies of other water mite species complexes are likely to reveal many more genetically and morphologically distinct species.  相似文献   
55.
Local delivery of viral vectors can enhance the efficacy of therapies by selectively affecting necessary tissues and reducing the required vector dose. Pluronic F127 is a thermosensitive polymer that undergoes a solution–gelation (sol–gel) transition as temperature increases and can deliver vectors without damaging them. While pluronics can be spread over large areas, such as the surface of an organ, before gelation, they lack sufficient adhesivity to remain attached to some tissues, such as the surface of the heart or mucosal surfaces. Here, we utilized blends of pluronic F127 and polycarbophil (PCB), a mucoadhesive agent, to provide the necessary adhesivity for local delivery of viral vectors to the cardiac muscle. The effects of PCB concentration on adhesive properties, sol–gel temperature transition and cytocompatibility were evaluated. Rheological studies showed that PCB decreased the sol–gel transition temperature at concentrations >1% and increased the adhesive properties of the gel. Furthermore, these gels were able to deliver viral vectors and transduce cells in vitro and in vivo in a neonatal mouse apical resection model. These gels could be a useful platform for delivering viral vectors over the surface of organs where increased adhesivity is required.  相似文献   
56.
57.

Background

Tamoxifen (TAM) is a well characterized breast cancer drug and selective estrogen receptor modulator (SERM) which also has been associated with a small increase in risk for uterine cancers. TAM's partial agonist activation of estrogen receptor has been characterized for specific gene promoters but not at the genomic level in vivo.Furthermore, reducing uncertainties associated with cross-species extrapolations of pharmaco- and toxicogenomic data remains a formidable challenge.

Results

A comparative ligand and species analysis approach was conducted to systematically assess the physiological, morphological and uterine gene expression alterations elicited across time by TAM and ethynylestradiol (EE) in immature ovariectomized Sprague-Dawley rats and C57BL/6 mice. Differential gene expression was evaluated using custom cDNA microarrays, and the data was compared to identify conserved and divergent responses. 902 genes were differentially regulated in all four studies, 398 of which exhibit identical temporal expression patterns.

Conclusion

Comparative analysis of EE and TAM differentially expressed gene lists suggest TAM regulates no unique uterine genes that are conserved in the rat and mouse. This demonstrates that the partial agonist activities of TAM extend to molecular targets in regulating only a subset of EE-responsive genes. Ligand-conserved, species-divergent expression of carbonic anhydrase 2 was observed in the microarray data and confirmed by real time PCR. The identification of comparable temporal phenotypic responses linked to related gene expression profiles demonstrates that systematic comparative genomic assessments can elucidate important conserved and divergent mechanisms in rodent estrogen signalling during uterine proliferation.  相似文献   
58.
Jeanette Edwards 《Ethnos》2018,83(4):724-743
Family history research is popular in England. As a social practice it straddles social class and is confined to neither the middle nor the working classes, but shows an enthusiastic and flourishing interest in the workings of social class and in micro-histories of the region. This article focuses on experts in family history research in a region of the north west of England where it is referred to colloquially as ‘family treeing’. Here family treeing is inflected by a post-industrial landscape and recent social and economic transformations with attendant threats to working-class life and dignity. Family treeing is about caring for the dead, but it is also, significantly, about caring for the living, and not only kin. It is an active practice of belonging both to people and places, and entails constant acts of reciprocity.  相似文献   
59.
Financial stress is widely believed to cause health problems. However, policies seeking to relieve financial stress by limiting debt levels of poor households may directly worsen their economic well-being. We evaluate an alternative policy – increasing the repayment flexibility of debt contracts. A field experiment randomly assigned microfinance clients to a monthly or a traditional weekly installment schedule (N = 200). We used cell phones to gather survey data on income, expenditure, and financial stress every 48 hours over seven weeks. Clients repaying monthly were 51 percent less likely to report feeling “worried, tense, or anxious” about repaying, were 54 percent more likely to report feeling confident about repaying, and reported spending less time thinking about their loan compared to weekly clients. Monthly clients also reported higher business investment and income, suggesting that the flexibility encouraged them to invest their loans more profitably, which ultimately reduced financial stress.  相似文献   
60.
The Cdc6 protein is an essential component of pre-replication complexes (preRCs), which assemble at origins of DNA replication during the G1 phase of the cell cycle. Previous studies have demonstrated that, in response to ionizing radiation, Cdc6 is ubiquitinated by the anaphase promoting complex (APC(Cdh1)) in a p53-dependent manner. We find, however, that DNA damage caused by UV irradiation or DNA alkylation by methyl methane sulfonate (MMS) induces Cdc6 degradation independently of p53. We further demonstrate that Cdc6 degradation after these forms of DNA damage is also independent of cell cycle phase, Cdc6 phosphorylation of the known Cdk target residues, or the Cul4/DDB1 and APC(Cdh1) ubiquitin E3 ligases. Instead Cdc6 directly binds a HECT-family ubiquitin E3 ligase, Huwe1 (also known as Mule, UreB1, ARF-BP1, Lasu1, and HectH9), and Huwe1 polyubiquitinates Cdc6 in vitro. Degradation of Cdc6 in UV-irradiated cells or in cells treated with MMS requires Huwe1 and is associated with release of Cdc6 from chromatin. Furthermore, yeast cells lacking the Huwe1 ortholog, Tom1, have a similar defect in Cdc6 degradation. Together, these findings demonstrate an important and conserved role for Huwe1 in regulating Cdc6 abundance after DNA damage.  相似文献   
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