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91.

Background

One strategy to address health problems related to insufficient physical activity is to examine modifiable neighborhood characteristics associated with active transportation.

Purpose

The aim of this study is to evaluate whether neighborhoods with more aesthetic amenities (sidewalk cafés, street trees, and clean sidewalks) and fewer safety hazards (pedestrian-auto fatalities and homicides) are associated with active transportation.

Methods

The 2003 Community Health Survey in New York City, which asked about active transportation (walking or bicycling >10 blocks) in the past 30 days, was linked to ZIP-code population census and built environment characteristics. Adjusted associations were estimated for dichotomous (any active transportation versus none) and continuous (trip frequency) active transportation outcomes.

Results

Among 8,034 adults, those living near sidewalk cafés were 10 % more likely to report active transportation (p?=?0.01). Homicide rate was associated with less frequent active transportation among those reporting any active transportation (p?=?0.002).

Conclusions

Investments in aesthetic amenities or homicide prevention may help to promote active transportation.
  相似文献   
92.
Islet xenotransplantation represents an attractive solution to overcome the shortage of human islets for use in type 1 diabetes. The wide‐scale application of clinical islet xenotransplantation, however, requires that such a procedure takes place in a specifically and tightly regulated environment. With a view to promoting the safe application of clinical islet xenotransplantation, a few years ago the International Xenotransplantation Association (IXA) published a Consensus Statement that outlined the key ethical and regulatory requirements to be satisfied before the initiation of xenotransplantation studies in diabetic patients. This earlier IXA Statement also documented a disparate regulatory landscape among different geographical areas. This situation clearly fell short of the 2004 World Health Assembly Resolution WHA57.18 that urged Member States “to cooperate in the formulation of recommendations and guidelines to harmonize global practices” to ensure the highest ethical and regulatory standards on a global scale. In this new IXA report, IXA members who are active in xenotransplantation research in their respective geographic areas herewith briefly describe changes in the regulatory frameworks that have taken place in the intervening period in the various geographic areas or countries. The key reassuring take‐home message of the present report is that many countries have embraced the encouragement of the WHO to harmonize the procedures in a more global scale. Indeed, important regulatory changes have taken place or are in progress in several geographic areas that include Europe, Korea, Japan, and China. Such significant regulatory changes encompass the most diverse facets of the clinical application of xenotransplantation and comprise ethical aspects, source animals and product specifications, study supervision, sample archiving, patient follow‐up and even insurance coverage in some legislations. All these measures are expected to provide a better care and protection of recipients of xenotransplants but also a higher safety profile to xenotransplantation procedures with an ultimate net gain in terms of international public health.  相似文献   
93.
The hemagglutinins of influenza viruses isolated from humans typically prefer binding to sialic acid in an alpha2,6 linkage. Presumably, the virus uses the presence of these receptors on the respiratory tract to gain entrance into the host cell. The ST6Gal I sialyltransferase knock-out mouse lacks the main enzyme necessary for the attachment of alpha2,6 sialic acid to N-linked glycoproteins on the cell surface. Yet even in the absence of detectable alpha2,6 sialic acid in the mouse respiratory tract, human influenza viruses can still infect these mice and grow to similar titers in the lung and trachea as compared to wild-type animals. This work demonstrates that the presence of a major alpha2,6 sialic acid on N-linked glycoproteins is not essential for human influenza virus infection in mice.  相似文献   
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95.
Immunohistochemical analyses (IHC) of biomarkers are extensively used for tumor characterization and as prognostic and predictive measures. The current standard of single slide analysis assumes that one 5 microM section is representative of the entire tumor. We used our automated image analysis technology (AQUA) using a modified IHC technique with fluorophores to compare estrogen receptor (ER) expression in multiple blocks/slides from cases of primary breast cancer with the objective of quantifying tumor heterogeneity within sections and between blocks. To normalize our ER scores and allow slide-to-slide comparisons, 0.6 microm histospots of representative breast cancer cases with known ER scores were assembled into a 'gold standard array' (GSA) and placed adjacently to each whole section. Overall, there was excellent correlation between AQUA scores and the pathologist's scores and reproducibility of GSA scores (mean linear regression R value 0.8903). Twenty-nine slides from 11 surgical cases were then analyzed totaling over 2000 AQUA images. Using standard binary assignments of AQUA (>10) and pathologist's (>10%) scores as being positive, there was fair concordancy between AQUA and pathologist scores (73%) and between slides from different blocks from the same cases (75%). However using continuous AQUA scores, agreement between AQUA and pathologist was far lower and between slides from different blocks from the same cases only 19%. Within individual slides there was also significant heterogeneity in a scattered pattern, most notably for slides with the highest AQUA scores. In sum, using a quantitative measure of ER expression, significant block-to-block heterogeneity was found in 81% of cases. These results most likely reflect both laboratory-based variability due to lack of standardization of immunohistochemistry and true biological heterogeneity. It is also likely to be dependent on the biomarker analyzed and suggests further studies should be carried out to determine how these findings may affect clinical decision-making processes.  相似文献   
96.
Food insecurity heightens risk for poor mental health and psychosocial functioning. Higher levels of future orientation influence numerous desirable behaviors. However, limited evidence exists on the association between food insecurity and future orientation, particularly in low-resource settings. The objective of this study was to examine the association between food insecurity and future orientation of Ghanaian youth and their parents. The study included a cross-sectional sample of 2656 youth and 2656 parents from 8 of Ghana’s 10 regions. Food insecurity was measured using the Household Food Insecurity Access Scale. Future orientation in the Ghanaian context was measured using three distinct factors adapted from the School Success Profile and the Consideration of Future Consequences scale. We analyzed our data using hierarchical linear modeling, with a three-level linear random-intercept model with covariates. Results suggest an inverse relationship between food insecurity and future orientation of youth and their parents. Food insecurity was consistently and significantly associated with lower orientation toward success (β = ?0.18, 95% confidence interval [CI] = ?0.22, ?0.14) and higher uncertainty of the future (β = 0.22, 95% CI = 0.17, 0.28) among youth, as well as lower consideration of future consequences (β = ?0.15, 95% CI = ?0.23, ?0.06) among parents. Additionally, severe food insecurity was associated with the lowest future orientation scores for youth and their parents. Our findings indicate that, under conditions of food insecurity, youth and their parents lose sight of the future, which may come at a great cost. Encouraging individuals to engage in thinking about the future or to create future images of their selves may not be meaningful if their basic needs, including access to food, are not met. Programs that provide opportunities to generate income and accumulate assets may have a twofold effect of increasing access to food and improving future orientation.  相似文献   
97.
98.
99.
Convection-based renal replacement therapies (RRTs) have the potential to improve patient outcomes when compared to diffusion-based RRT such as hemodialysis (HD), but have limited clearance rates. We propose and characterize multipoint dilution hemofiltration (MPD-HF), a purely convective blood purification technology which removes the fundamental filtration limit associated with convective RRT resulting in clearance rates on par with HD. In MPD-HF, filtration of liquid and solutes occurs along the length of the hollow fibers that convey the blood, and substitution fluid is pushed into the fibers at multiple points along their length. Since multiple filtration and dilution steps are contained within one pass of the blood through the hollow fiber, the fraction of fluid that can be filtered may be increased to allow a high clearance rate that removes a wide range of toxins. In vitro tests yielded an average steady-state filtrate fraction of 68%, exceeding commercial HDF cartridge filtrate fractions by a factor of approximately 3. The molecular weights of molecules cleared spans up to the cutoff of 66 kDa for albumin.  相似文献   
100.
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