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Obtaining spirometric testing and providing those results to individuals who smoke has been advocated as a motivational tool to improve smoking cessation. However, its effectiveness is not known. We conducted a systematic review to determine if this approach improves rates of smoking cessation. Data sources included MEDLINE (1966 to October 2005), the Cochrane Library, and experts in the field. Eligible randomized controlled trials (RCTs) enrolled at least 25 smokers per arm, evaluated spirometry with associated counseling or in combination with other treatments, followed subjects at least 6 months, and provided smoking abstinence rates. Results from nonrandomized studies also were summarized. The primary outcome was patient-reported long-term (at least 6 months) sustained abstinence with biological validation. Additional outcomes included self-reported abstinence and point-prevalence abstinence. Seven RCTs (N = 6,052 subjects) met eligibility criteria. Follow-up duration ranged from 9 to 36 months. In six trials, the intervention group received concomitant treatments previously demonstrated to increase cessation independently. The range of abstinence was 3%-14% for control subjects and 7%-39% among intervention groups, statistically significantly in favor of intervention in four studies. The only RCT that assessed the independent contribution of spirometry in combination with counseling demonstrated a nonsignificant 1% improvement in patient-reported point-prevalence abstinence at 12 months in the group that received spirometry plus counseling versus counseling alone (6.5% versus 5.5%). Findings from observational studies were mixed, and the lack of controls makes interpretation problematic. Available evidence is insufficient to determine whether obtaining spirometric values and providing that information to patients improves smoking cessation compared with other smoking cessation methods. Spirometric values are of limited benefit as a predictor of smoking cessation or as a tool to "customize" smoking cessation strategies.  相似文献   
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The magnitudes of cerebral somatosensory evoked potentials (SEPs), following stimulation of cutaneous or muscle afferents in the upper limb, are reduced during active and passive movements of the fingers. The generalizability of such a movement effect was tested for lower limb events. We measured SEP magnitudes following activation of cutaneous (sural) and mixed (tibial) nerves during the flexion phase of active and passive rhythmic movements of the human lower limb. In eight volunteers, 150 SEPs per condition were recorded from Cz' referenced to Fpz'. Compared to stationary controls, both active and passive movements significantly depressed the early SEP components (P1-N1) [mean values, to 12.8%, 9.9% respectively for tibial nerve and to 29.6%, 25.6% for sural nerve stimulation, p < 0.05]. The attenuation was still observed when only one leg was moved and with stimulation at an earlier point in the flexion phase of movement. Visual fixation did not significantly affect P1-N1 amplitudes, compared to eyes closed. As previously shown, soleus H reflexes with stable M waves were significantly depressed during the movements (p < 0.05). The general construct may be that centripetal flow initiated from somatosensory receptors during limb movement leads to modulation of both spinal and cortical responses following large diameter cutaneous or muscle afferent activation.  相似文献   
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OBJECTIVE: To review the literature investigating the effects of parental affective illness on children over the past decade. METHOD: A computerized search of articles published over the past 10 years was completed. Articles were reviewed and relevant studies are presented. RESULTS: Over the course of the past 10 years a number of longitudinal studies have confirmed that children of affectively ill parents are at a greater risk for psychiatric disorders than children from homes with non-ill parents. Life table estimates indicate that by the age of 20 a child with an affectively ill parent has a 40% chance of experiencing an episode of major depression. Children from homes with affectively ill parents are more likely to exhibit general difficulties in functioning, increased guilt, and interpersonal difficulties as well as problems with attachment. Marital difficulties, parenting problems, and chronicity and severity of parental affective illness have been associated with the increased rates of disorder observed in these children. CONCLUSION: The presence of depression in parents should alert clinicians to the fact that their children also may be depressed and therefore in need of services. J. Am. Acad. Child Adolesc.  相似文献   
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PURPOSE: A number of reports have documented the relationship between pretreatment hemoglobin level and local control and/or survival in the treatment of cervix, bladder, and advanced head and neck tumors. Consideration of correcting anemia before initiation of radiation therapy may prove increasingly important as clinical trials use intensive induction chemotherapy in the treatment of head and neck carcinomas. Neoadjuvant chemotherapy may produce anemia, which in turn may reduce the effectiveness of subsequent irradiation. MATERIALS AND METHODS: One hundred nine patients with T1-2N0 squamous cell carcinoma of the glottic larynx were treated with definitive radiotherapy at the Fox Chase Cancer Center between June 1980 and November 1990. Follow-up times ranged from 26 to 165 months (median, 82). RESULTS: The 2-year local control rate for patients who presented with a hemoglobin level < or = 13 g/dL was 66%, compared with 95% for patients with a hemoglobin level more than 13 g/dL (P = .0018). The 2-year survival rate for patients with a hemoglobin level < or = 13 g/dL was 46%, compared with 88% for patients with a hemoglobin level more than 13 g/dL (P < .001). Cox proportional hazards regression analysis showed that hemoglobin level (P = .0016) was the only variable that significantly influenced local control (P = .0016) and survival (P < .0001). CONCLUSION: Patients who presented with hemoglobin levels more than 13 g/dL had significantly higher local control and survival rates. The strong apparent correlation between hemoglobin level, local control, and survival supports consideration of correcting anemia before initiation of radiation therapy.  相似文献   
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Used in concert with the Kirchhoff transformation, implicit differentiation of the discretized boundary integral equations governing the conduction of heat in solids with temperature dependent thermal conductivity is shown to generate an accurate and economical approach for computation of shape sensitivities. For problems with specified temperature and heat flux boundary conditions, a linear problem results for both the analysis and sensitivity analysis. In problems with either convection or radiation boundary conditions, a non-linear problem is generated. Several iterative strategies are presented for the solution of the resulting sets of non-linear equations and the computational performances examined in detail. Multi-zone analysis and zone condensation strategies are demonstrated to provide substantive computational economies in this process for models with either localized non-iinear boundary conditions or regions of geometric insensitivity to design variables. A series of non-linear example problems is presented that have closed form solutions. Exact anaytical expressions tor the shape sensitivities associated with these problems are developed and these are compared with the sensitivities computed using the boundary element formulation.  相似文献   
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BACKGROUND: The purpose of this study was to determine if sacrosidase, a liquid produced from Saccharomyces cerevisiae containing 6000 IU of sucrase activity per mg protein, prevented symptoms of diarrhea, abdominal cramps, gas, and bloating in patients with congenital sucrase-isomaltase deficiency (CSID) consuming a normal sucrose and carbohydrate-containing diet. METHODS: Twenty-eight children (aged 5 months to 11 years) underwent a randomized, double-blind trial consisting of two phases: 1) three sucrose breath H2 tests with three single-dose treatments (placebo, sacrosidase, and sacrosidase plus milk), and 2) a dose-response phase consisting of four multidose treatments, each for 10 days of full-strength sacrosidase, 1:10 dilution, 1:100 dilution, and 1:1000 dilution. Patients who weighed less than or equal to 15 kg received a dose of sacrosidase and those who weighed more than 15 kg received 2 ml. For the dose-response phase each patient consumed a normal diet. The number of stools and severity of symptoms were recorded daily for each concentration of sacrosidase administered and compared to a baseline period during which the patient took no sacrosidase and consumed a sucrose/starch-free diet. Data were analyzed using an ANOVA model and the nonparameter Wilcoxon signed-rank test. RESULTS: Breath H2 excretion decreased significantly when patients received sacrosidase or sacrosidase plus milk compared to placebo during sucrose breath tests. During the dose-response phase significant treatment differences were observed between the two higher concentrations and the two lower concentrations of sacrosidase for both total stools (p < 0.001) and total symptom score (p = 0.003). Higher concentrations of sacrosidase were associated with fewer stools and a greater number of formed or hard stools compared to lower concentrations and compared to the baseline period. Higher concentrations were also associated with fewer symptoms of gas, abdominal cramps, or bloating, but no differences in vomiting. The only significant adverse event was wheezing in one child with a history of asthma. CONCLUSIONS: Sacrosidase is a safe, effective, well-accepted treatment to prevent gastrointestinal symptoms in patients with CSID consuming a normal diet.  相似文献   
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