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1.
The effect of weight loss with anorectic medications on sleep apnea, non-insulin-dependent diabetes, and steatohepatitis is illustrated in three cases from practice in a clinical nutrition setting. Prevention of obesity, a chronic disorder, is preferable, but when obesity becomes a major obstacle in the care of patients with respiratory, cardiovascular, and metabolic disorders and osteoarthritis, an intense course of weight reduction using anorectic medications under medical and dietetic guidance is essential for patients' survival and reduction of medical cost.  相似文献   
2.

Background

Several investigations have studied gait variability of individuals with anterior cruciate ligament (ACL) deficiency; however, the effect of dual-tasking on the gait variability of these individuals remained unclear. The aim of the present study was to determine the effect of gait speed and dual-tasking on knee flexion–extension variability in subjects with and without ACL deficiency.

Methods

The knee flexion–extension Lyapunov exponent (LyE) was measured in 22 ACL-deficient (Mean±SD) (25.95?±?4.69?years) and 22 healthy subjects (24.18?±?3.32?years). They walked at three levels of gait speed in isolation or concurrently with a cognitive task.

Results

Repeated-measure analyses of variance (ANOVAs) demonstrated that the interaction of group by gait speed was statistically significant. As the gait speed increased from low to high, the knee flexion–extension LyE significantly decreased for the subjects with ACL deficiency (effect size: 0.57, P?=?0.01). The interaction of group by cognitive load was not statistically significant (P?=?0.07). In addition, the ACL-deficient subjects had statistically slower reaction times than healthy subjects during the dual-task compared with the single-task condition.

Conclusions

The ACL-deficient and healthy individuals had a tendency to maintain safe gait. It seems that the ACL-deficient subjects sacrificed the cognitive task more than the healthy individuals to pay more attention toward gait. Additionally, it seems that the gait speed was more challenging than cognitive load on the stride-to-stride variability in the individuals with ACL deficiency.  相似文献   
3.
Background ContextAnnular repair devices offer a solution to recurrent disc herniations by closing an annular defect and lowering the risk of reherniation. Given the significant risk of neurologic injury from device failure it is imperative that a reliable preclinical model exists to demonstrate a high load to failure for the disc repair devices.PurposeTo establish a preclinical model for disc herniation and demonstrate how changes in species, intervertebral disc height and Pfirrmann classification impacts failure load on an injured disc. We hypothesized that: (1) The force required for disc herniation would be variable across disc morphologies and species, and (2) for human discs the force to herniation would inversely correlate with the degree of disc degeneration.Study designAnimal and human cadaveric biomechanical model of disc herniation.MethodsWe tested calf lumbar spines, bovine tail segments and human lumbar spines. We first divided individual lumbar or tail segments to include the vertebral bodies and disc. We then hydrated the specimens by placing them in a saline bath overnight. A magnetic resonance images were acquired from human specimens and a Pfirrmann classification was made. A stab incision measuring 25% of the diameter of the disc was then done to each specimen along the posterior intervertebral disc space. Each specimen was placed in custom test fixtures on a servo-hydraulic test frame (MTS, Eden Prarie, MN) such that the superior body was attached to a 10,000 lb load cell and the inferior body was supported on the piston. A compressive ramping load was placed on the specimen in load control at 4 MPa/sec stopping at 75% of the disc height. Load was recorded throughout the test and failure load calculated. Once the test was completed each specimen was sliced through the center of the disc and photos were taken of the cut surface.ResultsFifteen each of calf, human, and bovine tail segments were tested. The failure load varied significantly between specimens (p<.001) with human specimens having the highest average failure load (8154±2049 N). Disc height was higher for lumbar/bovine tail segments as compared to calf specimens (p<.001) with bovine tails having the highest disc height (7.1±1.7 mm). Similarly, human lumbar discs had a cross sectional area that was greater than both bovine tail/calf lumbar spines (p<.001). There was no correlation between disc height and failure load within each individual species (p>.05). Cross sectional area and failure load did not correlate with failure load for human lumbar spine and bovine tails (p>.05) but did correlate with calf spine (r=0.53, p=.04). There was a statistically significant inverse correlation between disc height and Pfirrmann classification for human lumbar spines (r=?0.84, p<.001). There was also a statistically significant inverse relationship between Pfirrmann classification and failure load (r=?0.58, p=.02).ConclusionsWe have established a model for disc herniation and have shown how results of this model vary between species, disc morphology, and Pfirrmann classification. Both hypotheses were accepted: The force required for disc herniation was variable across species, and the force to herniation for human spines was inversely correlated with the degree of disc degeneration. We recommend that models using human intervertebral discs should include data on Pfirrmann classification, while biomechanical models using calf spines should report cross sectional area. Failure loads do not vary based on dimensions for bovine tails.Clinical SignificanceOur analysis of models for disc herniation will allow for quicker, reliable comparisons of failure forces required to induce a disc herniation. Future work with these models may facilitate rapid testing of devices to repair a torn/ruptured annulus.  相似文献   
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7.
Reactive oxygen metabolites (ROM) have been postulated to contribute to the development of various carcinomas, including colon cancer. Indeed, the effects of ROM scavengers are being tested for chemoprevention of adenocarcinoma of the colon. However, there has been no evidence to indicate that high levels of ROM are indeed present in cancerous tissue. In this study, we used a chemiluminescence probe to estimate ROM levels in cancerous and neighboring noncancerous colonic tissues from seven patients with colon cancer. Cancerous tissues contained significantly (p < 0.05) more luminol‐enhanced chemiluminescence (4,808 ± 2,282 counts/min/mg protein) than neighboring noncancerous tissues (2,175 ± 1,111). The addition of an ROM scavenger, catalase (2, 4, and 8 μg/ml), to the tissue suspension inhibited chemiluminescence produced by both noncancerous (—74%, —85%, and —71%) and cancerous (—11%, —61%, and — 53 %) tissues. This study shows that colonic cancerous tissue contains high levels of ROM, which may play an important role in the pathogenesis of colon cancer.  相似文献   
8.
To determine whether patients with colon cancer metabolize β‐carotene differently from benign colon polyp patients, a normal control group (n = 13) and groups of resected colon polyp patients (n = 29) or resected colon cancer patients (Dukes A and BI, n = 21) were supplemented with placebo or β‐carotene (30 mglday) taken with their morning meals for three months. Serum samples at zero and three months of the study were anlayzed blindly for retinoic acid and β‐carotene. The results showed that β‐carotene levels in the serum of colon polyp and colon cancer groups were 8‐ to 12‐fold higher than in the untreated control or the placebo‐treated groups. The benign polyp subjects (n = 17) receiving β‐carotene showed a significant rise in serum trans‐retinoic acid at three months compared with Time 0. The trans‐retinoic acid values from the colon cancer group receiving β‐carotene (n = 11) or placebo (n = 10) were significantly lower than the values from the β‐carotene‐supplemented colon polyp group. It appears that trans‐retinoic acid levels in response to β‐carotene supplementation are different between treated cancer and benign patients because of different body demands for retinoic acid.  相似文献   
9.
Sustainable development (SD) policies targeting marine economic sectors, designed to alleviate poverty and conserve marine ecosystems, have proliferated in recent years. Many developing countries are providing poor fishing households with new fishing boats (fishing capital) that can be used further offshore as a means to improve incomes and relieve fishing pressure on nearshore fish stocks. These kinds of policies are a marine variant of traditional SD policies focused on agriculture. Here, we evaluate ex ante economic and environmental impacts of provisions of fishing and agricultural capital, with and without enforcement of fishing regulations that prohibit the use of larger vessels in nearshore habitats. Combining methods from development economics, natural resource economics, and marine ecology, we use a unique dataset and modeling framework to account for linkages between households, business sectors, markets, and local fish stocks. We show that the policies investing capital in local marine fisheries or agricultural sectors achieve income gains for targeted households, but knock-on effects lead to increased harvest of nearshore fish, making them unlikely to achieve conservation objectives in rural coastal economies. However, pairing an agriculture stimulus with increasing enforcement of existing fisheries’ regulations may lead to a win–win situation. While marine-based policies could be an important tool to achieve two of the United Nations Sustainable Development Goals (alleviate poverty and protect vulnerable marine resources), their success is by no means assured and requires consideration of land and marine socioeconomic linkages inherent in rural economies.

Coastal and island nations are adopting “blue growth” sustainable development (SD) policies to alleviate poverty and conserve vulnerable ocean resources. Generally speaking, SD policies manage resources and direct investments in order to meet current and future human needs and aspirations, without endangering the natural systems (1). The feasibility and potential of SD has been the focus of decades of academic research; many regard the consideration of economic, social, environmental, and institutional needs and linkages as fundamental to successful policy design and implementation (26). Given their novelty, what constitutes a blue growth policy is not universal (7), but like traditional SD policies that focus on land-based sectors such as agriculture, manufacturing, and energy sectors (8, 9), blue growth policies seek to achieve social, economic, and environmental goals simultaneously (10). Blue growth policies attempt to achieve these goals by supporting marine-based industries such as offshore fishing, aquaculture, shipping, and tourism (11, 12). The marine focus has reinvigorated SD efforts of international organizations (including the Global Environmental Facility, United Nations Food and Agriculture Organization, the European Union, and The World Bank) that have collectively invested hundreds of millions of dollars into the development and monitoring of blue growth programs (1216).While small-scale artisanal fishers consider a variety of factors when making fishing decisions (17), evidence suggests allocation of time is, in part, based on relative returns to labor (1821). Thus, some blue growth policies attempt to alter returns to fishing relative to alternative income-generating activities as a way to achieve both poverty alleviation and conservation objectives. For example, if poor fishing households are incentivized to participate in offshore fishing, it may lead to increased household incomes and reduced fishing pressure on overexploited nearshore fish stocks (22, 23). Policies enforcing and increasing the regulation of fishing activities are also considered important to achieving blue growth objectives (10, 24).Many SD policies are designed to reduce upfront costs of switching to more sustainable livelihoods. Historically, large-scale fisheries receive the majority of subsidy benefits (25), arguably to the detriment of small-scale fisheries who are often outcompeted by industrialized operations (26). Recently, however, developing countries including Kenya, the Philippines, India, Tanzania, Vietnam, and Indonesia have been investing in programs that bolster the fishing capacity of small-scale and artisanal fishermen (2733). These programs are designed to help small-scale fishers access larger or better vessels and gear, allowing them to reach more plentiful fishing grounds, compete with commercial vessels, and relieve pressure on vulnerable nearshore fisheries.Despite the recent surge in popularity, we lack evidence that these marine-based SD policies will achieve both poverty reduction and conservation objectives when implemented in rural economies. The complexity of coupled natural–human systems makes it difficult to measure the ex post performance of SD policies, especially in marine environments (34, 35). Additionally, local market failures due to high transportation costs and poorly developed marketing infrastructure (36) can lead to locally defined prices that fluctuate with changes in local supply and demand; local prices may distort household responses to policies, leading to unintended environmental consequences (3740). Because local market failures are more common in rural economies in developing countries, methods and lessons learned from studies of industrialized fisheries in developed countries may not be relevant. Rather, management of fisheries in rural coastal economies may be more successful if market imperfections, alternative livelihood options, and ecological feedback are considered (20, 4147).Recent studies explore the causal impacts of land-based SD policy instruments in developing countries (4856). A key finding of these studies is that community heterogeneity is an important factor in policy performance. However, findings from forestry research do not necessarily carry over to marine settings because fish resources are mobile and regenerate relatively quickly, and, typically, access rights to fisheries are not well defined. This study begins to address the need for research examining responses to SD policy in rural coastal economies.We use a coupled natural–human modeling framework to estimate the ex ante impacts of common SD policies. Our ex ante mechanistic approach that includes a general equilibrium local economy model captures important dynamic feedback between the economy and health of the fish stocks. Indeed, other researchers have studied the correlations between markets and ecosystems in coastal communities in developing countries (44, 5759). However, the theoretical structure of our analysis approach allows us to examine the causal mechanisms between policy and its outcomes. Our model captures the feedback between economic sectors and households within the economy (Fig. 1, details in SI Appendix). This broad scope is necessary to estimate the extent to which policies targeting poor households in a community also impact nontargeted households (knock-on effects). For example, a policy supporting a subset of fishing households could be detrimental to other households that harvest from the same fish stocks and compete in the same input and output markets.Open in a separate windowFig. 1.A conceptual framework for the bioeconomic local general equilibrium model. Households are represented by four representative groups and may produce goods and services (e.g., agricultural, offshore and nearshore fish, retail, and restaurants) available in local, and possibly global, markets. The simulated policies provide different types of capital to poor households and may also restrict use of fishing capital.Here, we estimate the impacts of two common marine fisheries policies (provision of offshore fishing vessels and increased enforcement of fishing regulations) and an alternative agricultural policy (provision of agricultural capital) in a rural coastal economy. To estimate the impacts of these SD policies in coastal economies, we use a modeling approach that has been developed using theory from development economics, natural resource economics, and marine ecology (37, 60). Introducing new features to the framework, we develop a model of a rural economy capable of disentangling fisher participation in two distinct fishing activities and household consumption of two fish goods. We use microeconomic data collected from household and business surveys to parameterize and calibrate our model, allowing us to realistically estimate policy impacts. An inherent strength to our methodology is the ability to adjust the structure of the model to represent alternative economies. We demonstrate how the model can be used to predict policy outcomes for a typology of rural coastal economies.Although combining policies that simultaneously target marine and agricultural sectors is currently not part of the dialogue on the adoption of blue SD policies around the world (e.g., see The World Bank’s strategy document for its Blue Economy Program and PROBLUE (13)), we find that pairing policy instruments that target both sectors—increased enforcement of vessel regulations and capital investments in the agricultural sector—is better able to achieve both conservation and poverty reduction goals.Why is an agricultural policy combined with enforcement capabilities of marine fishing regulations able to achieve a win–win while marine-focused SD policies are not? Our coupled natural–human modeling framework highlights the mechanisms leading to this counterintuitive outcome. That is, investing in the agricultural sector increases the returns to agricultural labor, which in turn creates upward pressure on wages and encourages a reduction in labor allocated to nearshore fishing. At the same time, the increased wealth in the local economy due to greater agricultural productivity drives up demand for nearshore fish. Although higher prices of fish draw some labor back into the fishery, increased enforcement of vessel regulations prevents fishers from illegally using larger boats in the nearshore habitat as a means to increase harvests. Without coupling increased enforcement and agricultural subsidy, the higher demand for fish would lead to increased harvests in the nearshore environment and lower fish stocks over time.  相似文献   
10.
Abdominal Radiology - To evaluate 3T mpMRI characteristics of transition zone and peripheral zone index prostate cancer lesions stratified by Gleason Score and PI-RADSv2 with whole mount...  相似文献   
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