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101.
102.
Recurrent respiratory papillomatosis is the most common neoplasm of the larynx in childhood. Extension into lung parenchyma occurs in less than 1% of patients and has a low risk of malignant transformation. Treatment options for intrapulmonary spread have shown limited success. We describe a case of recurrent respiratory papillomatosis with extensive parenchymal involvement and adenosquamous carcinoma in a 14-year-old girl.  相似文献   
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Ontogeny of Vestibular Compound Action Potentials in the Domestic Chicken   总被引:1,自引:0,他引:1  
Compound action potentials of the vestibular nerve were measured from the surface of the scalp in 148 chickens (Gallus domesticus). Ages ranged from incubation day 18 (E18) to 22 days posthatch (P22). Responses were elicited using linear acceleration cranial pulses. Response thresholds decreased at an average rate of –0.45 dB/day. The decrease was best fit by an exponential model with half-maturity time constant of 5.1 days and asymptote of approximately –25.9 dB re:1.0 g/ms. Mean threshold approached within 3 dB of the asymptote by ages P6–P9. Similarly, response latencies decreased exponentially to within 3% of mature values at ages beyond P9. The half-maturity time constant for peripheral response peak latencies P1, N1, and P2 was comparable to thresholds and ranged from approximately 4.6 to 6.2 days, whereas central peaks (N2, P3, and N3) ranged from 2.9 to 3.4 days. Latency-intensity slopes for P1, N1, and P2 tended to decrease with age, reaching mature values within approximately 100 hours of hatching. Amplitudes increased as a function of age with average growth rates for response peaks ranging from 0.04 to 0.09 μV/day. There was no obvious asymptote to the growth of amplitudes over the ages studied. Amplitude-intensity slopes also increased modestly with age. The results show that gravity receptors are responsive to transient cranial stimuli as early as E19 in the chicken embryo. The functional response of gravity receptors continues to develop for many days after all major morphological structures are in place. Distinct maturational processes can be identified in central and peripheral neural relays. Functional improvements during maturation may result from refinements in the receptor epithelia, improvements in central and peripheral synaptic transmission, increased neural myelination, as well as changes in the mechanical coupling between the cranium and receptor organ.  相似文献   
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BACKGROUND: Sweat testing is a noninvasive technique for monitoring drug exposure in treatment, criminal justice, and employment settings. METHODS: We evaluated cocaine excretion in 9 participants' sweat after they received 3 low doses (75 mg/70 kg) of cocaine HCl subcutaneously within 1 week and, 3 weeks later, 3 high doses (150 mg/70 kg). Six additional participants completed portions of the study. PharmChek sweat patches (n = 1390) were collected throughout a 3-week washout period, reflecting previously self-administered drugs, and during and after controlled dosing. RESULTS: Cocaine was the primary analyte detected with 24% of patches positive at the gas chromatography-mass spectrometry limit of quantification of 2.5 ng/patch and 7% of patches at the proposed Substance Abuse and Mental Health Services Administration cutoff of 25 ng/patch. Ecgonine methyl ester (EME) was detected more often and at generally higher concentrations than benzoylecgonine. In patches containing both metabolites, there was no statistically significant difference in the benzoylecgonine/EME ratio based on length of patch wear. During washout, 2 participants' weekly patches tested positive (> or =25 ng/patch) during the first week; one remained positive during week 2; and none were positive during week 3. Cocaine and EME were detectable within 2 h; benzoylecgonine was not detected until 4-8 h after low doses and slightly sooner after high doses. The majority of drug was excreted within 24 h. Over 70% of weekly patches worn during low doses were positive for cocaine (> or =25 ng/patch), increasing to 100% during high doses. CONCLUSION: Sweat testing is an effective and reliable method of monitoring cocaine exposure.  相似文献   
107.

Background Context

Negative beliefs are known to influence treatment outcome in patients with spine pain (SP). The impact of positive beliefs is less clear.

Purpose

We aimed to assess the influence of positive and negative beliefs on baseline and treatment responses in patients with SP.

Study Design/Setting

A retrospective cross-sectional and longitudinal analysis of prospectively collected data of outpatient physical therapy patients with SP was carried out. Questionnaires administered before and during treatment included the STarT Back distress scale (negative beliefs), and expectation and self-efficacy questions (positive beliefs).

Patient Sample

Patients with SP with a baseline assessment and follow-up assessment comprised the study sample.

Outcome Measure

Perceived disability was measured using the Oswestry Disability Index (ODI) or the Neck Disability Index (NDI). A clinical meaningful change (minimum clinically important difference [MCID]) was defined as decrease in ODI or NDI of ≥30%.

Methods

We used the Akaike Information Criterion from the first imputed dataset of the prediction model to select predictor variables. Prediction models were fitted to the outcome variables.

Results

In the cross-sectional analysis, 1,695 low back pain (LBP) episodes and 487 neck pain (NP) episodes were analyzed. STarT Back Screening Tool (SBST)-distress was positively associated with perceived disability in both LBP (beta 2.31, 95% confidence interval [CI] 1.75–2.88) and NP (beta 2.57, 95% CI 1.47–3.67). Lower self-efficacy was negatively associated with more perceived disability for LBP (beta 0.50, 95% CI 0.29–0.72) but not for NP, whereas less positive expectations was associated with more perceived disability in NP (beta 0.57, 95% CI 0.02–1.12) but not in LBP. In the longitudinal analysis, 607 LBP episodes (36%) and 176 (36%) NP episodes were included. SBST-distress did not predict treatment outcome in spine patients. In LBP, patients with a lower positive expectation were less likely to experience an MCID in perceived disability (odds ratio [OR] per point increase 0.89, 95% CI 0.83–0.96), and there was a similar trend in NP (OR per point increase 0.90, 95% CI 0.79–1.03). In patients with LBP, lower self-efficacy at baseline was associated with a higher likelihood that an MCID was achieved (OR per point increase 1.09, 95% CI 1.01–1.19). In NP, self-efficacy was not included in the final model.

Conclusions

Our study demonstrates that both negative and positive beliefs are associated with perceptions of disability. However, in this study, only positive beliefs were associated with treatment outcome.  相似文献   
108.
The CD40/CD40L costimulatory pathway plays a crucial role in allograft rejection. The purpose of this study was to determine the effectiveness of anti-CD40L monoclonal antibody (mAb) treatment as a method to induce long-term, tissue-specific, immunologic hyporesponsiveness to peripheral nerve allografts. Sciatic nerve allografts were performed from BALB/c donor mice into C57BL/6 recipients. Anti-CD40L mAb (1 mg) was administered intraperitoneally to recipient mice on postoperative days 0, 1, and 2. After a 14-, 28-, or 60-day recovery period, the mice were rechallenged with either a BALB/c cardiac or peripheral nerve allograft. Rejection was assessed by measuring the production of interferon gamma (IFN-gamma), interleukin (IL)-2, -4, and -5, and alloantibodies immunoglobulin (Ig) M and IgG. IFN-gamma, IL-2, IL-4, IL-5, IgM, and IgG responses were much lower in the anti-CD40L mAb group compared with controls. Nerve allograft and nerve isograft rechallenge 60 days following the original nerve allotransplantation produced low cytokine responses, whereas cardiac allograft rechallenge produced high cytokine production, indicative of acute rejection. Short-term anti-CD40L treatment may cause long-term, tissue-specific, immunologic hyporesponsiveness. This may allow time for native axons to traverse the transplanted nerve allograft and replace the graft with autogenous peripheral nerve tissue.  相似文献   
109.
We have examined the association of alcohol intake during various life periods, by beverage category, with breast cancer risk in Greece. A hospital-based case-control study was performed in Athens, Involving 820 women with breast cancer as well as 795 orthopedic patients and 753 healthy visitor controls-Relative risk patterns were very similar with either control series, which were therefore combined to increase precision of the estimates. Drinkers of beer were at significantly elevated risk for breast cancer [odds ratio (OR), 1.34 (95% confidence interval, 1.05-1.71)]. However, drinkers of other alcoholic beverages were not at increased risk. Among beer drinkers there was no dose-response, and drinkers of both beer and other beverages had a lower OR compared to drinkers of beer only. By contrast, drinkers of 3 or more glasses of alcohol per day, mostly of spirits, were at elevated risk for breast cancer [OR for 3 - < 4 glasses per day, 3.01 (1.14-7.95); OR for 4 or more glasses per day, 3.79 (1.05-13.71)]. Reported frequency of consumption was a stronger predictor of breast cancer risk than either duration-weighted total consumption or consumption before the age of 30 years. There were no coherent patterns for interaction with menopausal status, obesity or use of menopausal estrogens. The association of very low levels of alcohol intake with breast cancer risk may be due to confounding, whereas drinking 3 or more glasses of alcoholic beverages daily appears to genuinely increase breast cancer risk, perhaps by acting as a late-stage growth enhancing factor. However, the data also are compatible with a linear relationship that has no threshold.  相似文献   
110.
Background. Ebstein’s anomaly in the severely symptomatic neonate is usually fatal. Until recently, successful repair has not been reported and various palliative operations have been associated with prohibitive mortality. Recently, we published our initial results with biventricular repair in 3 severely symptomatic neonates. We now update our experience with emphasis on the evolution of our surgical technique and the medium-term follow-up of these patients.

Methods. Since 1994, 8 severely symptomatic neonates and young infants underwent biventricular repair by one surgeon. Six had Ebstein’s anomaly and 2 had physiologically similar pathology with severe tricuspid valve dysplasia, cyanosis, and gross cardiomegaly. One Ebstein patient (2 months old) had undergone a Starnes operation elsewhere. Weight of the patients at operation ranged from 2.1 to 6.4 kg (mean 2.7 kg). Five patients had either anatomical (n = 3) or functional (n = 2) pulmonary atresia. Severe (4/4) tricuspid regurgitation was present in all except 1 (Starnes operation), and cardiothoracic ratio exceeded 0.85 in all patients. Echocardiography severity scores were >1.5 in 6 (grade 4/4) and 1.3 in 1 (grade 3/4). Repair consisted of tricuspid valve repair, reduction atrioplasty, relief of right ventricular outflow tract obstruction, partial closure of atrial septal defect, and correction of all associated cardiac defects. Technique of tricuspid valve repair evolved over time: 3 had Danielson-type repairs, 3 had DeVega-type repairs, and 2 had complex repairs.

Results. One patient died in hospital: a 2.1 kg patient with tricuspid dysplasia, anatomical pulmonary atresia, and hypoplastic pulmonary arteries. The other 7 patients are all in functional class I and in sinus rhythm. Although 3 patients had symptomatic tachyarrhythmias before surgery, no child has experienced SVT after discharge. At recent echocardiography 4 patients had mild tricuspid regurgitation, and 2 had mild-moderate (2/4) tricuspid regurgitation. Three patients are now 7 years old, 2 are almost 2 years old, and the remaining 2 patients are 1 year old.

Conclusions. Surgical repair of the severely symptomatic neonate with Ebstein’s anomaly is feasible and safe. The repair appears durable and with good medium-term outcome.  相似文献   

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