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951.
Background contextSpine-related health-care expenditures accounted for $86 billion dollars in 2005, a 65% increase from 1997. However, when adjusting for inflation, surgeons have seen decreased reimbursement rates over the last decade.PurposeTo assess contribution of surgeon fees to overall procedure cost, we reviewed the charges and reimbursements for a noninstrumented lumbar laminectomy and compared the amounts reimbursed to the hospital and to the surgeon at a major academic institution.Study design/settingRetrospective review of costs associated with lumbar laminectomies.Patient sampleSeventy-seven patients undergoing lumbar laminectomy for spinal stenosis throughout an 18-month period at a single academic medical center were included in this study.Outcome measuresCost and number of laminectomy levels.MethodsThe reimbursement schedule of six academic spine surgeons was collected over 18 months for performed noninstrumented lumbar laminectomy procedures. Bills and collections by the hospital and surgeon professional fees were comparatively analyzed and substratified by number of laminectomy levels and patient insurance status. Unpaired two-sample Student t test was used for analysis of significant differences.ResultsDuring an 18-month period, patients underwent a lumbar laminectomy involving on average three levels and stayed in the hospital on average 3.5 days. Complications were uncommon (13%). Average professional fee billing for the surgeon was $6,889±$2,882, and collection was $1,848±$1,433 (28% overall, 30% for private insurance, and 23% for Medicare/Medicaid insurance). Average hospital billing for the inpatient hospital stay minus professional fees from the surgeon was $14,766±$7,729, and average collection on such bills was $13,391±$7,256 (92% overall, 91% for private insurance, and 85% for Medicare/Medicaid insurance).ConclusionBased on this analysis, the proportion of overall costs allocated to professional fees for a noninstrumented lumbar laminectomy is small, whereas those allocated to hospital costs are far greater. These findings suggest that the current focus on decreasing physician reimbursement as the principal cost saving strategy will lead to minimal reimbursement for surgeons without a substantial drop in the overall cost of procedures performed.  相似文献   
952.
953.
BackgroundPrior studies have reported that students with overweight and obesity have impairments in performance IQ and executive function and worse school functioning in comparison with peers of normal weight. The present study assessed school and cognitive functioning in a sample of adolescents with severe obesity being evaluated for laparoscopic adjustable gastric banding.MethodsEligible candidates for bariatric surgery were referred for psychiatric evaluation, which included a semistructured clinical interview measuring school functioning and the vocabulary and matrix reasoning subtests of the Wechsler Abbreviated Scale of Intelligence (WASI).ResultsSelf-reported school problems were common, with 55.5% of adolescents failing a grade or subject, 38.7% attending summer school, and 17.8% failing a citywide examination. A significant relationship was observed between body mass index, estimated WASI IQ (r = ?.250; P = .005), and the vocabulary subtest (r = ?.241; P = .006), but not matrix reasoning (r = ?.126; P = NS).ConclusionEven among a sample of adolescents with severe obesity, increased body mass index was associated with lower WASI IQ and vocabulary subtest scores. Increasing awareness of potential cognitive and school problems in bariatric candidates among teachers, school counselors, and other mental health providers is an important first step to improving academic support and educational systems deficiencies for students with overweight and obesity.  相似文献   
954.
955.
Studies have demonstrated that patients are able to identify melanoma in many cases. A limitation to using self-examination as a means of melanoma detection is the fact that in certain areas of the body, such as the scalp, self-examination is difficult to adequately perform. This may be one of the reasons why scalp melanomas carry a worse prognosis than melanomas detected in other areas of the body. The authors present three cases of scalp melanomas that were detected by the patient’s hairdressers and suggest that with minimal training, hairdressers could become a valuable resource in assisting dermatologists in the early diagnosis of scalp melanoma.Melanoma has high cure rates when diagnosed early, but poor survival when found at an advanced stage. Most melanomas are visible on the skin, which allows for self-detection. In fact, in one report based on a population-based survey, 53 percent of melanomas were detected by patients, 26 percent by physicians, 17 percent by family, and three percent by others.1 Further, self-examination leads to decreased melanoma thickness in comparison to patients who do not perform self-examinations, with variable sensitivity data ranging from 25 to 93 percent, but high specificity of 83 to 97 percent.2 Despite the benefits of self-examination in early melanoma detection, this is often very difficult on the scalp. Most patients visit a hairdresser more frequently than they see a dermatologist, so there may be a role for training hairdressers in melanoma detection as they are likely to see the entire scalp in the course of their work. The authors present three cases of scalp melanomas in which the patients presented to outpatient clinics at the University of Pittsburgh Department of Dermatology after their hairdressers initally detected the melanomas.1-4  相似文献   
956.
Residual excess cement (REC) is a common complication of cement-retained prostheses and has been linked to periimplant disease. Removal of the cement residue may result in resolution of the issue if addressed early in the disease process. However, this is dependent upon the ability to locate and adequately remove the foreign material. This series of patient scenarios describes the ability to detect REC by using dental radiography. Characteristics related to cements and flow patterns specific to implants are addressed.  相似文献   
957.
Many features of posttraumatic stress disorder (PTSD) can be linked to exaggerated and dysregulated emotional responses. Central to the neurocircuitry regulating emotion are functional interactions between the amygdala and the ventromedial prefrontal cortex (vmPFC). Findings from human and animal studies suggest that disruption of this circuit predicts individual differences in emotion regulation. However, only a few studies have examined amygdala-vmPFC connectivity in the context of emotional processing in PTSD. The aim of the present research was to investigate the hypothesis that PTSD is associated with disrupted functional connectivity of the amygdala and vmPFC in response to emotional stimuli, extending previous findings by demonstrating such links in an understudied, highly traumatized, civilian population. 40 African-American women with civilian trauma (20 with PTSD and 20 non-PTSD controls) were recruited from a large urban hospital. Participants viewed fearful and neutral face stimuli during functional magnetic resonance imaging (fMRI). Relative to controls, participants with PTSD showed an increased right amygdala response to fearful stimuli (pcorr < .05). Right amygdala activation correlated positively with the severity of hyperarousal symptoms in the PTSD group. Participants with PTSD showed decreased functional connectivity between the right amygdala and left vmPFC (pcorr < .05). The findings are consistent with previous findings showing PTSD is associated with an exaggerated response of amygdala-mediated emotional arousal systems. This is the first study to show that the amygdala response may be accompanied by disruption of an amygdala-vmPFC functional circuit that is hypothesized to be involved in prefrontal cortical regulation of amygdala responsivity.  相似文献   
958.
This study investigated the relationship between white matter microstructure and the development of morphosyntax in a spoken narrative in typically developing children (TD) and in children with high functioning autism (HFA). Autism is characterized by language and communication impairments, yet the relationship between morphosyntactic development in spontaneous discourse contexts and neural development is not well understood in either this population or typical development. Diffusion tensor imaging (DTI) was used to assess multiple parameters of diffusivity as indicators of white matter tract integrity in language-related tracts in children between 6 and 13 years of age. Children were asked to spontaneously tell a story about at time when someone made them sad, mad, or angry. The story was evaluated for morphological accuracy and syntactic complexity. Analysis of the relationship between white matter microstructure and language performance in TD children showed that diffusivity correlated with morphosyntax production in the superior longitudinal fasciculus (SLF), a fiber tract traditionally associated with language. At the anatomical level, the HFA group showed abnormal diffusivity in the right inferior longitudinal fasciculus (ILF) relative to the TD group. Within the HFA group, children with greater white matter integrity in the right ILF displayed greater morphological accuracy during their spoken narrative. Overall, the current study shows an association between white matter structure in a traditional language pathway and narrative performance in TD children. In the autism group, associations were only found in the ILF, suggesting that during real world language use, children with HFA rely less on typical pathways and more on alternative ventral pathways that possibly mediate visual elements of language.  相似文献   
959.
Making flexible associations between what we see and what we do is important for many everyday tasks. Previous work in patients with focal lesions has shown that the control of saccadic eye movements in such contexts relies on a network of areas in the frontal cerebral cortex. These regions are reciprocally connected with structures in the basal ganglia although the contribution of these sub-cortical structures to oculomotor control in complex tasks is not well understood. We report the performance of patients with idiopathic Parkinsons disease (PDs) in a test which required learning and switching between arbitrary cue-saccade rules. In Experiment 1 feedback was given following each response which reliably indicated which of the two possible rules was correct. PDs were slower to learn the first cue-saccade association presented, but did not show increased error or reaction time switch costs when switching between two rules within blocks. In a follow up experiment the feedback given by the computer was adjusted to be probabilistic such that executing a response based upon the “correct” rule only resulted in positive feedback on 80% of trials. Under these conditions patients were impaired in terms of response latencies and number of errors. In all conditions PDs showed multi-stepping/hypometria of saccades consistent with a motoric deficit in executing actions based on cognitive cues. The findings are consistent with a role for the nigrostriatal dopamine system in the reinforcement of saccade-response-outcome associations. Intact performance of PDs when associations are not stochastically reinforced suggests that striatal learning systems are complemented by cognitive representations of task rules which are unaffected in the early stages of PD.  相似文献   
960.
[18F]FPEB is a positron emission tomography tracer which, in preclinical studies, has shown high specificity and selectivity toward the metabotropic glutamate receptor 5 (mGluR5). It possesses the potential to be used in human studies to evaluate mGluR5 function in a range of neuropsychiatric disorders, such as anxiety and Fragile X syndrome. To define optimal scan methodology, healthy human subjects were scanned for 6 hours following either a bolus injection (n=5) or bolus-plus-constant-infusion (n=5) of [18F]FPEB. Arterial blood samples were collected and parent fraction measured by high-performance liquid chromatography (HPLC) to determine the metabolite-corrected plasma input function. Time activity curves were extracted from 13 regions and fitted by various models to estimate VT and BPND. [18F]FPEB was well fitted by the two-tissue compartment model, MA1 (t*=30), and MRTM (using cerebellum white matter as a reference). Highest VT values were observed in the anterior cingulate and caudate, and lowest VT values were observed in the cerebellum and pallidum. For kinetic modeling studies, VT and BPND were estimated from bolus or bolus-plus-constant-infusion scans as short as 90 minutes. Bolus-plus-constant-infusion of [18F]FPEB reduced intersubject variability in VT and allowed equilibrium analysis to be completed with a 30-minute scan, acquired 90–120 minutes after the start of injection.  相似文献   
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