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The 331 million people of the United States are served by a complex and expensive healthcare system that accounts for nearly 18% of the country’s gross domestic product. Over 90% of patients are insured by private or government-funded plans, but despite high coverage and unusually high healthcare spending, vast disparities exist within the United States population based on demographics in terms of diagnosis, treatment, and outcomes of disease. Thoracic surgeons in the United States are trained to treat patients with diseases of the chest in the operative and perioperative settings, and can accomplish this training through multiple highly competitive pathways. Thoracic surgeons perform an average of 135 operations each per year which address diseases of the lungs, trachea, esophagus, chest wall, mediastinum, and diaphragm. Video assisted thoracoscopic surgeries are the most commonly performed procedures, which are primarily completed to treat lung cancer. Lung cancer is the deadliest and second most prevalent malignancy in the United States, with over 200,000 new cases expected this year. In addition to encouragement of smoking cessation and more attention to air pollutants, increased access to lung cancer screening has significantly expedited diagnosis and reduced mortality from lung cancer in the last several years. Thoracic surgeons in the United States are tasked with treating common yet highly morbid diseases of the chest in a patient population that is diverse in terms of race, socioeconomic status, and healthcare insurance coverage. As the population ages and a shortage of thoracic surgeons looms, the importance of early diagnosis, skillful surgical management, and attention to the disparities that exist in our system cannot be overstated. 相似文献
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Current theories on the etiology of idiopathic scoliosis 总被引:2,自引:0,他引:2
J A Byrd 《Clinical orthopaedics and related research》1988,(229):114-119
Review of the literature shows that the cause of idiopathic scoliosis remains unknown, although research has possibly eliminated some hypothetical causes. Abnormalities of disc, bone, muscle, and collagen do not appear to be etiological factors but, rather, reflect the effects of scoliosis on normal tissues. Although most patients with idiopathic scoliosis are thought of as tall and slender, it has not yet been proven that growth in this condition differs from normal. It is possible that idiopathic scoliosis is caused by multiple factors rather than a single factor. Perhaps there are different factors for curve initiation and curve progression. It appears that a brain stem or equilibrium abnormality does exist in patients with idiopathic scoliosis, although more research is needed to confirm and define the problem. There also may be a genetic basis for idiopathic scoliosis, as it does seem to occur within patients' families more frequently than in the general population. Whether these two factors form the basis for a multifactorial etiology of idiopathic scoliosis remains to be proven. 相似文献
66.
The PtdIns 3-Kinase/Akt Pathway Regulates Macrophage-Mediated ADCC against B Cell Lymphoma
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Trupti Joshi Latha P. Ganesan Carolyn Cheney Michael C. Ostrowski Natarajan Muthusamy John C. Byrd Susheela Tridandapani 《PLoS Clinical Trials》2009,4(1)
Macrophages are important effectors in the clearance of antibody-coated tumor cells. However, the signaling pathways that regulate macrophage-induced ADCC are poorly defined. To understand the regulation of macrophage-mediated ADCC, we used human B cell lymphoma coated with Rituximab as the tumor target and murine macrophages primed with IFNγ as the effectors. Our data demonstrate that the PtdIns 3-kinase/Akt pathway is activated during macrophage-induced ADCC and that the inhibition of PtdIns 3-kinase results in the inhibition of macrophage-mediated cytotoxicity. Interestingly, downstream of PtdIns 3-kinase, expression of constitutively active Akt (Myr-Akt) in macrophages significantly enhanced their ability to mediate ADCC. Further analysis revealed that in this model, macrophage-mediated ADCC is dependent upon the release of nitric oxide (NO). However, the PtdIns 3-kinase/Akt pathway does not appear to regulate NO production. An examination of the role of the PtdIns 3-kinase/Akt pathway in regulating conjugate formation indicated that macrophages treated with an inhibitor of PtdIns 3-kinase fail to polarize the cytoskeleton at the synapse and show a significant reduction in the number of conjugates formed with tumor targets. Further, inhibition of PtdIns 3-kinase also reduced macrophage spreading on Rituximab-coated surfaces. On the other hand, Myr-Akt expressing macrophages displayed a significantly greater ability to form conjugates with tumor cells. Taken together, these findings illustrate that the PtdIns 3-kinase/Akt pathway plays a critical role in macrophage ADCC through its influence on conjugate formation between macrophages and antibody-coated tumor cells. 相似文献
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Betsy Sleath Rex Ballinger David Covert Alan L. Robin John E. Byrd Gail Tudor 《The American journal of geriatric pharmacotherapy》2009,7(2):67-73
Objective: The purpose of the current study was to determine the self-reported prevalence of and factors associated with nonadherence with glaucoma medications in veteran outpatients.Methods: This survey study was conducted at a Veterans Affairs (VA) clinic. A survey was administered to patients with glaucoma. We calculated the percentage of self-reported adherence with glaucoma medications in each patient. Logistic regression was used to assess whether patient characteristics and difficulties with using glaucoma medications were related to patients' reporting that they were <100% adherent with their glaucoma medications in the previous week.Results: The survey was completed by 141 patients (men, 91.5%; mean [SD] age, 70.22 [11.60] years [range, 37–93 years]; black race, 45.4%; white race, 44.0%; “other” or data unavailable, 10.6%). Nonwhite patients were significantly less adherent in the previous week than were white patients (27.0% vs 11.3%; P < 0.05). A total of 67.4% patients reported ≥1 difficulty in using their glaucoma medications. The 3 most commonly reported difficulties were “drops fall on cheek” (29.1%), “too many drops come out” (20.6%), and “hard to read print” (17.0%). A total of 19.1% of patients self-reported using <100% of their glaucoma medications in the previous week. The number of difficulties reported was significantly associated with reporting being <100% adherent in the previous week (P<0.05).Conclusion: In this small sample of VA patients with glaucoma, adherence to glaucoma medications could be improved, especially among those who reported difficulties using their medications and those who were nonwhite. 相似文献
68.
The migrational disorders are a rare group of congenital malformations of the brain. They consist of the following entities--lissencephaly (agyria-pachygyria), pachygyria, schizencephaly, heterotopia and polymicrogyria. We studied 40 children with migrational disorders radiologically with CT and MR. This article (part I) deals with our patients their characteristic CT and MR findings along with their clinical presentation and course. These patients presented with one or a combination of the following symptoms, hypotonia, seizures, failure to thrive, microcephaly and occasionally hydrocephalus. These two groups of migrational disorders have abnormalities affecting the gyral-sulcal pattern of the cortex and gray-white matter distribution of the brain. MR provided better delineation of these disorders than CT. Because some forms of the migrational disorders can be inherited, it is extremely important for the radiologist to understand the characteristic findings for correct diagnosis which is essential for parental counseling. 相似文献
69.
Li Z Li FX Byrd D Deyhle GM Sesser DE Skeels MR Lamm SH 《Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine》2000,42(2):200-205
Environmental contamination of drinking water has been observed for perchlorate, a chemical able to affect thyroid function. This study examines whether that exposure affected the thyroid function of newborns. Neonatal blood thyroxine (T4) levels for days 1 to 4 of life were compared for newborns from the city of Las Vegas, Nevada, which has perchlorate in its drinking water, and those from the city of Reno, Nevada, which does not (detection limit, 4 micrograms/L [ppb]). This study is based on blood T4 analyses from more than 23,000 newborns in these two cities during the period April 1998 through June 1999. No difference was found in the mean blood T4 levels of the newborns from these two cities. Drinking water perchlorate levels measured monthly for Las Vegas ranged during this study period from non-detectable for 8 months to levels of 9 to 15 ppb for 7 months. Temporal differences in mean T4 level were noted in both cities but were unrelated to the perchlorate exposure. This study was sufficiently sensitive to detect the effects of gender, birth weight, and the day of life on which the blood sample was taken on the neonatal T4 level, but it detected no effect from environmental exposures to perchlorate that ranged up to 15 micrograms/L (ppb). 相似文献
70.
A prospective randomized study of pregnancy rates following intrauterine and intracervical insemination using frozen donor sperm 总被引:5,自引:0,他引:5
Cryopreserved sperm have lowered fertility when compared with fresh sperm in artificial insemination by donor programs. The purpose of this study was to compare pregnancy rates following intrauterine insemination (IUI) and intracervical insemination (ICI) with cryopreserved sperm in a prospective trial using the patient as her own control. A total of 154 patients were randomized into alternating treatment cycles and underwent 238 cycles of IUI and 229 cycles of ICI. The pregnancy rate per treatment cycle was 9.7% following IUI and 3.9% following ICI. Treatment outcome was influenced by patient age, ovulatory status, and endometriosis. Pregnancy success correlated well with the post-thaw survival of sperm and the number of motile cells inseminated. In spite of having normal semen parameters, some donors were found to have markedly reduced sperm fecundity. We conclude that IUI with cryopreserved sperm can be an effective treatment for couples with infertility, genetic indications, or other reasons. 相似文献