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51.
52.
A 53-year-old woman admitted to our department for histologically proven chronic hepatitis C had previously been treated with pegylated interferon-alpha2b (PEG-IFN) plus ribavirin. Combination therapy had been withdrawn after 5 weeks because of severe anemia (hemoglobin 8.2 g/dl) despite a reduction in ribavirin dose. A second liver biopsy showed moderate chronic hepatitis with portoportal and portocentral bridges (Ishak score: grading 14/18, staging 4-5/6). Consequently, the patient was retreated with 1.5 microg/kg body weight weekly PEG-IFN and 1000 mg/day ribavirin. Ribavirin was withdrawn about 3 months later because of anemia. After 1 month of PEG-IFN alone, hemoglobin had decreased further to reach 7.9 g/dl; consequently IFN was stopped. An elevated reticulocyte count, indirect bilirubin concentration, and lactic dehydrogenase (LDH) concentration, and a positive direct Coombs test (IgG3, C3d also for panagglutinant irregular antibodies on eluate) led us to diagnose autoimmune hemolytic anemia (AHA). The patient received 1 mg/kg body weight/day prednisone, and all parameters normalized within 20 days. This is the first case of IFN-related AHA during PEG-IFN plus ribavirin therapy. Physicians should be aware that PEG-IFN can be the cause of AHA during a ribavirin-containing regimen for chronic hepatitis C.  相似文献   
53.
The ability to associate a name to a face is a crucially relevant task in daily life. In this study, we investigated the neuronal basis of face-name retrieval in young subjects using repetitive transcranial magnetic stimulation (rTMS) over the left or right dorsolateral prefrontal cortex (DLPFC). The experimental task was composed of two study phases: an encoding phase and a retrieval phase. During the encoding phase, subjects saw a face (familiar or unfamiliar) followed by a name. During the retrieval phase, they saw the face together with two names and had to choose the name that was correctly associated with the face. rTMS was delivered only during retrieval. In addition, we evaluated the use of memory strategies during the task. Accordingly, subjects were subdivided into two groups: strategy users (SU) and no-strategy users (NSU). No rTMS effects were present for familiar face-name pairs, probably due to a ceiling effect. However, for unfamiliar face-name pairs, the different use of memory strategies resulted in different rTMS effects. The SU group showed a selective interference effect after right DLPFC stimulation, whereas the NSU group showed an effect after left DLPFC stimulation. Importantly, the overall performance of the two groups was comparable. We suggest that during memory retrieval the left DLPFC might be recruited when the subject does not apply deliberately a retrieval strategy whereas there is a shift to the right DLPFC if cognitive control processes that are engaged by strategies are needed to guide episodic retrieval.  相似文献   
54.
Exhaled nitric oxide (NO) is a recognized biomarker in the lower respiratory tract. The effect of large variation in body mass on exhaled NO in the same individuals is not well known. The aim of the study was to evaluate both the effect of severe obesity and the influence of weight reduction on exhaled NO. A consecutive series of 24 uncomplicated obese patients (OB), who had laparoscopic adjustable gastric banding (LAGB) and 15 healthy controls (HC) were studied. Body mass index (BMI), exhaled NO and respiratory function tests were assessed. Exhaled NO was lower in obese in comparison to HC (12.0+/-3.6ppb versus 15.8+/-4.0ppb, p=0.0035). A significant positive correlation was found between exhaled NO and BMI in HC, which was not evident in OB. Among the respiratory indexes, functional residual capacity was significantly associated to exhaled NO. After 1 year, 12 obese patients undergone to LAGB were re-evaluated. Mean BMI (kg/m(2)) decreased from 44.8 before surgery to 32.3 post-operatively. The exhaled NO increased from 11.8+/-3.2ppb before surgery to 14.9+/-3.1ppb 1 year post-operatively (p=0.0023, n=12). In conclusion exhaled NO is consistently reduced in severe obesity and it is restored after weight reduction. The relationship between exhaled NO, large body mass excess and decrease of resting lung volume in severe obesity deserves further studies.  相似文献   
55.
Cystic lesions of the thyroid are common findings. Although many thyroid cysts are of benign, some cases of hemorrhagic degenerative changes occur in neoplastic nodules, mostly follicular neoplasms and papillary carcinomas. The occurrence of hemorrhagic changes in medullary carcinomas has never been documented with aspirative cytological and histological pictures to the best of our knowledge. A case of medullary thyroid carcinoma with a large central hemorrhagic cyst is described, and the literature regarding the pathogenesis of this regression and the occurrence of cystic neoplasms in the thyroid is reviewed.  相似文献   
56.
BACKGROUND: Infection with human papillomavirus (HPV) is a necessary step in the progression to cervical cancer. Many methods for HPV testing are currently available, most developed to detect pools of HPV types. OBJECTIVES: To evaluate the HPV typing by molecular methods and to compare commercial kits with an established laboratory method. STUDY DESIGN: Eighty-four cervical samples found to be positive for HPV DNA by GP5+/6+-polymerase chain reaction-enzyme immunoassay-reverse line blotting (PCR-EIA-RLB) were re-tested with two commercial methods, INNO-LiPA and Amplisense HPV typing, able to identify the HPV type predicted by PCR-EIA-RLB in 76 and 67 samples, respectively. RESULTS: The INNO-LiPA assay revealed HPV DNA in 75/76 samples (98.7%; 95% CI, 0.93-0.99) that would contain HPV types identifiable by this assay. The Amplisense HPV assay revealed HPV DNA in 58/67 samples (86.6%; 95% CI, 0.76-0.93) containing HPV types detectable by this assay. For samples with a single infection, the unweighted kappa for concordance of HPV typing was 0.87 (95% CI, 0.78-0.97) for PCR-EIA-RLB versus INNO-LiPA, 0.94 (95% CI, 0.87-0.99) for INNO-LiPA versus Amplisense HPV, and 0.82 (95% CI, 0.70-0.94) for PCR-EIA-RLB versus Amplisense HPV typing. PCR-EIA-RLB revealed 12 multiple infections, INNO-LiPA revealed 14, and Amplisense HPV revealed 5. The agreement among tests for samples with multiple infections was lower, giving kappa values of 0.44 (95% CI, 0.18-0.70) for PCR-EIA-RLB versus INNO-LiPA, 0.52 (95% CI, 0.19-0.85) for PCR-EIA-RLB versus Amplisense HPV and 0.43 (95% CI, 0.12-0.74) for INNO-LiPA versus Amplisense HPV. CONCLUSIONS: In HPV-positive samples, the agreement among tests for HPV typing was high for single infections but markedly lower for infections with multiple HPV types.  相似文献   
57.
Summary The mechanical power (Wtot, W·kg–1) developed during ten revolutions of all-out periods of cycle ergometer exercise (4–9 s) was measured every 5–6 min in six subjects from rest or from a baseline of constant aerobic exercise [50%–80% of maximal oxygen uptake (VO2max)] of 20–40 min duration. The oxygen uptake [VO2 (W·kg–1, 1 ml O2 = 20.9 J)] and venous blood lactate concentration ([la]b, mM) were also measured every 15 s and 2 min, respectively. During the first all-out period, Wtot decreased linearly with the intensity of the priming exercise (Wtot = 11.9–0.25·VO2). After the first all-out period (i greater than 5–6 min), and if the exercise intensity was less than 60% VO2max, Wtot, VO2 and [la]b remained constant until the end of the exercise. For exercise intensities greater than 60% VO2max, VO2 and [la]b showed continuous upward drifts and Wtot continued decreasing. Under these conditions, the rate of decrease of Wtot was linearly related to the rate of increase of V [(d Wtot/dt) (W·kg–1·s–1) = 5.0·10–5 –0.20·(d VO2/dt) (W·kg–1·s–1)] and this was linearly related to the rate of increase of [la]b [(d VO2/dt) (W·kg–1·s–1) = 2.310–4 + 5.910–5·(d [la]b/dt) (mM·s–1)]. These findings would suggest that the decrease of Wtot during the first all-out period was due to the decay of phosphocreatine concentration in the exercising muscles occurring at the onset of exercise and the slow drifts of VO2 (upwards) and of Wtot (downwards) during intense exercise at constant Wtot could be attributed to the continuous accumulation of lactate in the blood (and in the working muscles).  相似文献   
58.

Background

A number of non-motor symptoms occurs in Parkinson Disease (PD), cognitive decline and mood disturbances representing the most prevalent.Recent studies reported that cognitive training could potentially help to attenuate cognitive deficits in patients with PD and several researches demonstrated a beneficial effect of active transcranial Direct Current Stimulation (tDCS) over the left dorsolateral prefrontal cortex (anode over left dorsolateral prefrontal cortex, cathode over right supraorbital area) on cognitive deficits and mood disturbances.

Objective

To investigate the effects of active tDCS combined with computerized cognitive training on cognition and mood disturbances in PD patients.

Methods

Twenty-two patients with PD were assigned to either active tDCS plus computerized cognitive training (CCT) or sham tDCS plus CCT groups. Each patient underwent two weeks' treatment of daily application of tDCS for 25?minutes during CCT focalized on functions related with prefrontal cortex. Each patient was evaluated at baseline, after treatment and at 3-month follow-up.

Results

A significant reduction of depressive symptoms was observed in the active tDCS group from baseline to post-treatment assessment and from baseline to 3-month follow-up. An improvement in cognitive performances, referring more specifically to language, attentional and executive functions, was observed in both groups post-treatment and at follow-up. However, phonemic verbal fluency showed significant greater changes from baseline in the active tDCS group.

Conclusions

We concluded that cognitive training along with active tDCS is a useful combined approach in the management of mood and cognitive dysfunctions in PD.  相似文献   
59.
Background and purpose:  Progressive non‐fluent aphasia (PNFA) is a neurodegenerative disorder that is characterized by non‐fluent speech with naming impairment and grammatical errors. It has been recently demonstrated that repetitive transcranial magnetic stimulation (rTMS) over the dorsolateral prefrontal cortex (DLPFC) improves action naming in healthy subjects and in subjects with Alzheimer’s disease. Purpose:  To investigate whether the modulation of DLPFC circuits by rTMS modifies naming performance in patients with PNFA. Methods:  Ten patients with a diagnosis of PNFA were enrolled. High‐frequency rTMS was applied to the left and right DLPFC and the sham (i.e. placebo) condition during object and action naming. A subgroup of patients with semantic dementia was enrolled as a comparison group. Results:  A repeated‐measure anova with stimulus site (sham, left and right rTMS) showed significant effects. Action‐naming performances during stimulation of both the left and right DLPFC were better than during placebo stimulation. No facilitating effect of rTMS to the DLPFC on object naming was observed. In patients with a diagnosis of semantic dementia, no effect of stimulation was reported. Conclusions:  Our study demonstrated that rTMS improved action naming in subjects with PNFA, possibly due to the modulation of DLPFC pathways and a facilitation effect on lexical retrieval processes. Future studies on the potential of a rehabilitative protocol using rTMS applied to the DLPFC in this orphan disorder are required.  相似文献   
60.
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