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51.
BackgroundIliotibial Band Syndrome (ITBS) is a common clinical condition likely caused by abnormal compressive forces to the iliotibial band (ITB). Stretching interventions are common in ITBS treatment and may predominantly affect tensor fascia latae (TFL). Another ITBS treatment is foam rolling, which may more directly affect the ITB. Shear wave ultrasound elastography (SWUE) measures real-time soft tissue stiffness, allowing tissue changes to be measured and compared.PurposeTo examine effects of foam rolling and iliotibial complex stretching on ITB stiffness at 0˚ and 10˚ of hip adduction and hip adduction passive range of motion (PROM).Study DesignRandomized controlled trial.MethodsData from 11 males (age = 30.5 ± 9.0 years, Body Mass Index (BMI) = 27.8 ± 4.0) and 19 females (age = 23.5 ± 4.9, BMI = 23.2 ± 2.1) were analyzed for this study. Subjects were randomly assigned to one of three groups: control, stretching, and foam rolling. Shear wave ultrasound elastography measurements included ITB Young’s modulus at the mid-thigh, the distal femur and the TFL muscle belly. ITB-to-femur depth was measured at mid-thigh level. Hip adduction PROM was measured from digital images taken during the movement.ResultsNo significant interactions or main effects were found for group or time differences in ITB Young’s modulus at the three measured locations. The ITB stiffness at the mid-thigh and distal femur increased with 10° adduction, but TFL stiffness did not increase. A main effect for adduction PROM was observed, where PROM increased 0.8˚ post-treatment (p = 0.02).ConclusionA single episode of stretching and foam rolling does not affect short-term ITB stiffness. The lack of ITB stiffness changes may be from an inadequate intervention stimulus or indicate that the interventions have no impact on ITB stiffness.Levels of Evidence1b  相似文献   
52.
Ecosystem-level impacts of two hurricane seasons were compared several years after the storms in the largest lagoonal estuary in the U.S., the Albemarle-Pamlico Estuarine System. A segmented linear regression flow model was developed to compare mass-water transport and nutrient loadings to a major artery, the Neuse River Estuary (NRE), and to estimate mean annual versus storm-related volume delivery to the NRE and Pamlico Sound. Significantly less water volume was delivered by Hurricane Fran (1996), but massive fish kills occurred in association with severe dissolved oxygen deficits and high contaminant loadings (total nitrogen, total phosphorus, suspended solids, and fecal bacteria). The high water volume of the second hurricane season (Hurricanes Dennis, Floyd, and Irene in 1999) delivered generally comparable but more dilute contaminant loads, and no major fish kills were reported. There were no discernable long-term adverse impacts on water quality. Populations of undesirable organisms, such as toxic dinoflagellates, were displaced down-estuary to habitats less conducive for growth. The response of fisheries was species-dependent: there was no apparent impact of the hurricanes on commercial landings of bivalve molluscs or shrimp. In contrast, interacting effects of hurricane floodwaters in 1999 and intensive fishing pressure led to striking reductions in blue crabs. Overall, the data support the premise that, in shallow estuaries frequently disturbed by hurricanes, there can be relatively rapid recovery in water quality and biota, and benefit from the scouring activity of these storms.  相似文献   
53.
OBJECTIVE: Recent reforms in the federal Medicaid program have attempted to integrate beneficiaries into the mainstream by providing them with managed care options. However, the effects of mainstreaming have not been systematically evaluated. DESIGN: Cross-sectional survey. SETTING/PARTICIPANTS: A sample of 478 adult, nonelderly asthmatics followed by a large Northern California medical group. MEASUREMENTS AND MAIN RESULTS: We examined differences in self-reported access by insurance status. Compared to patients with other forms of insurance, patients covered by the state's Medicaid program (Medi-Cal) were more likely to report access problems for asthma-related care, including difficulties in reaching a health care provider by telephone, obtaining a clinic appointment, and obtaining asthma medication. Adjusting for relevant clinical and sociodemographic variables, Medi-Cal patients were more likely to report at least one access problem compared to non-Medi-Cal patients (adjusted odds ratio [AOR], 3.34; 95% confidence interval [CI], 1.43 to 7.80). Patients reporting at least one access problem were also more likely to have made at least one asthma-related emergency department visit within the past year (AOR, 4.84; 95% CI, 2.41 to 9.72). Reported barriers to care did not translate into reduced patient satisfaction. CONCLUSIONS: Within this population of Medicaid patients, the provision of health insurance and care within the mainstream of an integrated health system was no guarantee of equal access as perceived by the patients themselves.  相似文献   
54.
Objective  To investigate how important treatment for emotional distress is to primary care patients in general and to primary care patients with depression, and to evaluate the types of mental health interventions they desire. Design  Patient surveys. Setting  Five private primary care practices. Measurements and main results  Patients' desire for treatment of emotional distress and for specific types of mental health interventions were measured, as well as patients' ratings of the impact of emotional distress, the frequency of depressive symptoms, and mental health functioning. Of the 403 patients, 33% felt that it was “somewhat important” and 30% thought it was “extremely important” that their physician tries to help them with their emotional distress. Patient desire for this help was significantly related to a diagnosis of depression (P<.001), perceptions about the impact of emotional distress (p<.001), and mental health functioning (p<.001). Among patients with presumptive diagnoses of major and minor depression, 84% and 79%, respectively, felt that it was at least somewhat important that they receive this help from their physician. Sixty-one percent of all primary care patients surveyed and 89% of depressed patients desired counseling; 23% of all patients and 33% of depressed patients wanted a medication; and 11% of all patients and 5% of depressed patients desired a referral to a mental health specialist. Conclusions  A majority of these primary care patients and almost all of the depressed patients felt that it was at least somewhat important to receive help from their physician for emotional distress. The desire for this help seems to be related to the severity of the mental health problem. Most of the patients wanted counseling, but relatively few desired a referral to a mental health specialist. Funded by grant R01 MH51067 from the National Institute of Mental Health.  相似文献   
55.
Protein-folding landscapes in multichain systems   总被引:1,自引:0,他引:1       下载免费PDF全文
Computational studies of proteins have significantly improved our understanding of protein folding. These studies are normally carried out by using chains in isolation. However, in many systems of practical interest, proteins fold in the presence of other molecules. To obtain insight into folding in such situations, we compare the thermodynamics of folding for a Miyazawa-Jernigan model 64-mer in isolation to results obtained in the presence of additional chains. The melting temperature falls as the chain concentration increases. In multichain systems, free-energy landscapes for folding show an increased preference for misfolded states. Misfolding is accompanied by an increase in interprotein interactions; however, near the folding temperature, the transition from folded chains to misfolded and associated chains is entropically driven. A majority of the most probable interprotein contacts are also native contacts, suggesting that native topology plays a role in early stages of aggregation.  相似文献   
56.
Nonalcoholic fatty liver disease(NAFLD)refers to the accumulation of fat(mainly triglycerides)within hepatocytes.Approximately 20%-30%of adults in the general population in developed countries have NAFLD;this trend is increasing because of the pandemicity of obesity and diabetes,and is becoming a serious public health burden.Twenty percent of individuals with NAFLD develop chronic hepatic inflammation[nonalcoholic steatohepatitis(NASH)],which can be associated with the development of cirrhosis,portal hypertension,and hepatocellular carcinoma in a minority of patients.And thus,the detection and diagnosis of NAFLD is important for general practitioners.Liver biopsy is the gold standard for diagnosing NAFLD and confirming the presence of NASH.However,the invasiveness of this procedure limits its application to screening the general population or patients with contraindications for liver biopsy.The development of noninvasive diagnostic methods for NAFLD is of paramount importance.This review focuses on the updates of noninvasive diagnosis of NAFLD.Besides,we review clinical evidence supporting a strong association between NAFLD and the risk of cardiovascular disease because of the cross link between these two disorders.  相似文献   
57.
In nature, mixed Borrelia burgdorferi infections are common and possibly can be acquired by either superinfection or coinfection. Superinfection by heterologous B. burgdorferi strains has been established experimentally, although the ability of homologous B. burgdorferi clones to superinfect a host has not been studied in detail. Information regarding any potential immune barriers to secondary infection also currently is unavailable. In the present study, the ability to superinfect various mouse models by homologous wild-type clones was examined and compared to superinfection by heterologous strains. To assess the ability of homologous B. burgdorferi clones to successfully superinfect a mouse host, primary- and secondary-infecting spirochetes were recovered via in vitro cultivation of collected blood or tissue samples. This was accomplished by generating two different antibiotic-resistant versions of the wild-type B31-A3 clone in order to distinguish superinfecting B. burgdorferi from primary-infecting spirochetes. The data demonstrate an inability of homologous B. burgdorferi to superinfect immunocompetent mice as opposed to heterologous strains. Attempts to superinfect different types of immunodeficient mice with homologous B. burgdorferi indicate that the murine innate immune system represents a major barrier to intrastrain superinfection. Consequently, the possibility of innate immunity as a driving force for B. burgdorferi heterogeneity during the enzootic cycle is discussed.  相似文献   
58.
The Maastricht IV/Florence Consensus Report and the Second Asia-Pacific Consensus Guidelines strongly recommend eradication of Helicobacter pylori(H.pylori)in patients with previous gastric neoplasia who have undergone gastric surgery.However,the guidelines do not mention optimal timing,eradication regimens,diagnostic tools,and follow-up strategies for patients undergoing gastrectomy and do not indicate if eradication of H.pylori reduces the risk of marginal ulcer or stump cancer in the residual stomach after gastrectomy.The purpose of this review is to provide an update which may help physicians to properly manage H.pylori infection in patients who have undergone gastric surgery.This review focuses on(1)the microenvironment change in the stomach after gastrectomy;(2)the phenomenon of spontaneous clearance of H.pylori after gastrectomy;(3)the effects of H.pylori on gastric atrophy and intestinal metaplasia after gastrectomy;(4)incidence and clinical features of ulcers developing after gastrectomy;(5)does eradication of H.pylori reduce the risk of gastric stump cancer in the residual stomach?(6)does eradication of H.pylori reduce the risk of secondary metachronous gastric cancer in the residual stomach?and(7)optimal timing and regimens for H.pylori eradication,diagnostic tools and follow-up strategies for patients undergoing gastrectomy.  相似文献   
59.
60.
Sensory systems across the brain are specialized for their input, yet some principles of neural organization are conserved across modalities. The pattern of anatomical connections from the primate auditory cortex to the temporal, parietal, and prefrontal lobes suggests a possible division into dorsal and ventral auditory processing streams, with the dorsal stream originating from more caudal areas of the auditory cortex, and the ventral stream originating from more rostral areas. These streams are hypothesized to be analogous to the well-established dorsal and ventral streams of visual processing. In the visual system, the dorsal processing stream shows substantially faster neural response latencies than does the ventral stream. However, the relative timing of putative dorsal and ventral stream processing has yet to be explored in other sensory modalities. Here, we compare distributions of neural response latencies from 10 different areas of macaque auditory cortex, confirmed by individual anatomical reconstructions, to determine whether a similar timing advantage is found for the hypothesized dorsal auditory stream. Across three varieties of auditory stimuli (clicks, noise, and pure tones), we find that latencies increase with hierarchical level, as predicted by anatomical connectivity. Critically, we also find a pronounced timing differential along the caudal-to-rostral axis within the same hierarchical level, with caudal (dorsal stream) latencies being faster than rostral (ventral stream) latencies. This observed timing differential mirrors that found for the dorsal stream of the visual system, suggestive of a common timing advantage for the dorsal stream across sensory modalities.  相似文献   
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