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991.
Summary. Increasing evidence has suggested that oxidative stress may be involved in the pathogenesis of amyotrophic lateral sclerosis (ALS). The antioxidant vitamin E (alpha-tocopherol) has been shown to slow down the onset and progression of the paralysis in transgenic mice expressing a mutation in the superoxide dismutase gene found in certain forms of familial ALS. The current study, a double blind, placebo-controlled, randomised, stratified, parallel-group clinical trial, was designed to determine whether vitamin E (5000mg per day) may be efficacious in slowing down disease progression when added to riluzole. Methods. 160 patients in 6 German centres with either probable or definite ALS (according to the El Escorial Criteria) and a disease duration of less than 5 years, treated with riluzole, were included in this study and were randomly assigned to receive either alpha-tocopherol (5000mg per day) or placebo for 18 months. The Primary outcome measure was survival, calculating time to death, tracheostomy or permanent assisted ventilation, according to the WFN-Criteria of clinical trials. Secondary outcome measures were the rate of deterioration of function assessed by the modified Norris limb and bulbar scales, manual muscle testing (BMRC), spasticity scale, ventilatory function and the Sickness Impact Profile (SIP ALS/19). Patients were assessed at entry and every 4 months thereafter during the study period until month 16 and at a final visit at month 18. Vitamin E samples were taken for compliance check and Quality Control of the trial. For Safety, a physical examination was performed at baseline and then every visit until the treatment discontinuation at month 18. Height and weight were recorded at baseline and weight alone at the follow-up visits. A neurological examination as well as vital signs (heart rate and blood pressure), an ECG and VEPs were recorded at each visit. Furthermore, spontaneously reported adverse experiences and serious adverse events were documented and standard laboratory tests including liver function tests performed. For Statistical Analysis, the population to be considered for the primary outcome measure was an intent-to-treat (ITT) population which included all randomised patients who had received at least one treatment dose (n=160 patients). For the secondary outcome measures, a two way analysis of variance was performed on a patient population that included all randomised patients who had at least one assessment after inclusion. Results. Concerning the primary endpoint, no significant difference between placebo and treatment group could be detected either with the stratified Logrank or the Wilcoxon test. The functional assessments showed a marginal trend in favour of vitamin E, without reaching significance. Conclusion. Neither the primary nor the secondary outcome measures could determine whether a megadose of vitamin E is efficacious in slowing disease progression in ALS as an add-on therapy to riluzol. Larger or longer studies might be needed. However, administration of this megadose does not seem to have any significant side effects in this patient population.  相似文献   
992.
Fatal vascular outcomes following major orthopedic surgery   总被引:1,自引:0,他引:1  
Major orthopedic surgery is known to be associated with potentially serious arterial and venous vascular complications, although uncertainty exists about current event rates. Using electronic databases and investigator contact, we identified randomized and cohort studies reporting overall mortality and fatal vascular events. Where possible, studies reporting high autopsy rates (>60%) were examined. Pooled incidences were calculated from eligible studies. For Autopsy studies: Pooled overall mortality and fatal pulmonary embolism for patients undergoing elective hip and knee replacement without prophylaxis could not be calculated, while with prophylaxis they were 0.44% (95% confidence interval 0.02 to 0.87%) and 0.43% (0.01 to 0.85%). For patients undergoing hip fracture surgery, the corresponding rates without prophylaxis were 15.9% (14.5 to 17.3%) and 1.9% (1.4 to 2.4%). With prophylaxis, mortality and fatal pulmonary embolismrates were 8.5% (7.3 to 9.7%) and 1.0% (0.6 to 1.5%). Among Cohort studies: Pooled overall mortality and fatal pulmonary embolism for patients undergoing elective hip and knee replacement without prophylaxis were 0.93% (0.57 to 1.29%) and 0.36% (0.14 to 0.59%). For patients receiving prophylaxis (7 to 14 days), mortality and fatal pulmonary embolism were 0.57% (0.51 to 0.62%) and 0.18% (0.14 to 0.21%). Patients undergoing hip fracture surgery receiving prophylaxis hadmortality and fatal pulmonary embolismrates of 3.2% (2.8 to 3.6%) and 0.30% (0 to 0.61%). Vascular events contributed towards approximately 50% of all deaths with similar proportions due to ischemic heart disease, cardiac failure and pulmonary embolism. In conclusion, although prophylaxis results in a reduction in overall mortality and fatal pulmonary embolism, vascular events continue to be a common cause of mortality.  相似文献   
993.
BACKGROUND: Functional neuroimaging may elucidate the pathophysiologic features of anxiety disorders and the site of action of anxiolytic drugs. A large body of evidence suggests that the amygdala and associated limbic structures play a critical role in the expression of anxiety and may be treatment targets for anxiolytic drugs. OBJECTIVE: To determine whether lorazepam dose-dependently attenuates blood oxygenation level-dependent functional magnetic resonance imaging (BOLD fMRI) activation in the amygdala and associated limbic structures during an emotion face assessment task. PARTICIPANTS AND DESIGN: Fifteen healthy volunteers participated in a double-blind, placebo-controlled, randomized dose-response study. Subjects underwent imaging 3 times (at least a week apart) and were given either a single-dose placebo or 0.25 mg or 1.0 mg of lorazepam 1 hour prior to an MRI session. During fMRI, subjects completed an emotion face assessment task, which has been shown to elicit amygdala activation. MAIN OUTCOME MEASURES: The BOLD-fMRI activation in amygdala, insula, and medial prefrontal cortex during the emotion face assessment task. RESULTS: Lorazepam significantly attenuated the BOLD-fMRI signal in a dose-dependent manner in bilateral amygdala and insula but not in the medial prefrontal cortex. Lorazepam did not affect the BOLD-fMRI signal in the primary visual cortex. CONCLUSIONS: The current finding provides the first neuroimaging evidence of a dose-dependent change induced by an established therapeutic agent in brain regions known to be critical for the mediation of anxiety. This investigation may help to support the use of BOLD-fMRI with pharmacological probes to investigate the neural circuits underlying anxiety and the use of fMRI as a tool in the development of new anxiolytic agents.  相似文献   
994.
BACKGROUND: Panic disorder is a prevalent, often disabling condition among patients in the primary care setting. Although numerous studies have assessed the effectiveness of treatments for depression in primary care, few such studies have been conducted for panic disorder. OBJECTIVE: To implement and test the effectiveness of a combined pharmacotherapy and cognitive-behavioral intervention for panic disorder tailored to the primary care setting. DESIGN: Randomized, controlled study comparing intervention to treatment as usual. SETTING: Six primary care clinics associated with 3 university medical schools, serving an ethnically and socioeconomically diverse patient population. PARTICIPANTS: Two hundred thirty-two primary care patients meeting DSM-IV criteria for panic disorder. Comorbid mental and physical disorders were permitted, provided these did not contraindicate the treatment to be provided and were not acutely life threatening. INTERVENTION: Patients were randomized to receive either treatment as usual or an intervention consisting of a combination of up to 6 sessions (across 12 weeks) of cognitive-behavioral therapy (CBT) modified for the primary care setting, with up to 6 follow-up telephone contacts during the next 9 months, and algorithm-based pharmacotherapy provided by the primary care physician with guidance from a psychiatrist. Behavioral health specialists, the majority inexperienced in CBT for panic disorder, were trained to deliver the CBT and coordinated overall care, including pharmacotherapy. MAIN OUTCOMES MEASURES: Proportion of subjects remitted (no panic attacks in the past month, minimal anticipatory anxiety, and agoraphobia subscale score <10 on Fear Questionnaire) and responding (Anxiety Sensitivity Index score <20) and change over time in World Health Organization Disability Scale and short form 12 scores. RESULTS: The combined cognitive-behavioral and pharmacotherapeutic intervention resulted in sustained and gradually increasing improvement relative to treatment as usual, with significantly higher rates at all points of both the proportion of subjects remitted (3 months, 20% vs 12%; 12 months, 29% vs 16%) and responding (3 months, 46% vs 27%; 12 months, 63% vs 38%) and significantly greater improvements in World Health Organization Disability Scale (all points) and short form 12 mental health functioning (3 and 6 months) scores. These effects were obtained in spite of similar rates of delivery of guideline-concordant pharmacotherapy to the 2 groups. CONCLUSION: Delivery of evidence-based CBT and medication using the collaborative care model and a CBT-naive, midlevel behavioral health specialist is feasible and significantly more effective than usual care for primary care panic disorder.  相似文献   
995.
The information-motivation-behavioral skills (IMB) model (Fisher & Fisher, 1992) was used as the theoretical framework for predicting unprotected sexual behavior among substance abusing men and women diagnosed with serious mental illnesses (n = 320; 150 men and 170 women, primarily of minority ethnicity). In a structural equation model, gender, HIV transmission knowledge, and motivational variables of pro-condom norms and attitudes, and perceived susceptibility predicted behavioral skills markers: condom use skills and condom use self-efficacy. Along with the other variables in the model, condom skills and condom self-efficacy were hypothesized to predict condom use over a six-month period. Results showed that greater condom skills were predicted by female gender, positive condom attitudes, and transmission knowledge. Engaging in lower rates of unprotected sex was predicted by pro-condom norms, less perceived susceptibility, and greater condom self-efficacy. Positive attitudes toward condoms had a significant indirect effect on rates of unprotected sex, exerting its influence through condom use self-efficacy. Results suggest that changing personal attitudes about condoms and reinforcing pro-condom attitudes among significant others will encourage condom use among seriously mentally ill (SMI) adults who are at high risk for HIV and other sexually transmitted diseases (STDs).  相似文献   
996.
Nilsen KE  Walker MC  Cock HR 《Epilepsia》2005,46(2):179-187
PURPOSE: To characterize in detail a model of focal neocortical epilepsy. METHODS: Chronic focal epilepsy was induced by injecting 25-50 ng of tetanus toxin or vehicle alone (controls) into the motor neocortex of rats. EEG activity was recorded from electrodes implanted at the injection site, along with facial muscle electromyographic (EMG) activity and behavioral monitoring intermittently for up to 5 months in some animals. Drug responsiveness was assessed by using the antiepileptic drugs (AEDs) diazepam (DZP) and phenytoin (PHT) delivered systemically, while 1,2,3,4-tetrahydro-6-nitro-2,3-dioxo-benzo[f]quinoxaline-7-sulfonamide (NBQX), a competitive antagonist at AMPA receptors, was administered directly to the brain to investigate the potential benefits of focal drug delivery. RESULTS: Tetanus toxin induced mild behavioral seizures that persisted indefinitely in all animals. EEG spiking activity, occurring up to 80% of the time, correlated with clinical seizures consisting of interrupted behavioral activity, rhythmic bilateral facial twitching, and periods of abrupt motor arrest. Seizures were refractory to systemic administration of DZP and PHT. However, focal delivery of NBQX to the seizure site reversibly reduced EEG and behavioral seizure activity without detectable side effects. CONCLUSIONS: This study provides a long-term detailed characterisation of the tetanus toxin model. Spontaneous, almost continuous, well-tolerated seizures occur and persist, resembling those seen in neocortical epilepsy, including cortical myoclonus and epilepsia partialis continua. The seizures appear to be similarly resistant to conventional AEDs. The consistency, frequency, and clinical similarity of the seizures to refractory epilepsy in humans make this an ideal model for investigation of both mechanisms of seizure activity and new therapeutic approaches.  相似文献   
997.
Fibrous papule of the nose is a common benign lesion of dermal fibroblast lineage. Two unusual variants have been described, namely, fibrous papule with granular cells and fibrous papule with clear fibrocytes. We report a second case series (six cases) of clear cell fibrous papule to add to the first series of 9 cases. Clinical and histologic features in our cases are similar to those in the first series. All of our specimens were dome-shaped, 2- to 5-mm skin-colored to slightly erythematous papules on the faces of three male and three female adults ranging from 18 to 48 years of age. All but one lesion were on the nose. Clinical differential diagnoses included fibrous papule, verruca, basal cell carcinoma, and a variety of other neoplasms. Histologically, dermal aggregates of clear cells with finely granular to vacuolated cytoplasm, and centrally located nuclei, were found. Most specimens also contained ectatic capillaries, and all showed evidence of irritation or trauma. Periodic acid-Schiff stain was negative in all specimens to which it was applied (5/6). Neural, melanocytic, and epithelial origins were eliminated by negative staining with S-100, Mart-1, cytokeratins, epithelial membrane antigen, and carcinoembryonic antigen, performed on some of the specimens. A mesenchymal nature was confirmed in one specimen staining strongly positive for vimentin. Five of six cases stained positively for CD68, and all five cases studied were strongly and diffusely positive for NKI/C3. Factor XIIIa stain highlighted scattered dendritic cells within the lesion but was otherwise negative in all six cases studied. Recognition of this variant of fibrous papule is important to distinguish this benign lesion from other clear cell neoplasms.  相似文献   
998.
OBJECTIVE: Although studies have suggested that comorbid medical illness can affect the outcome of patients with depression, little is known about whether medical illness comorbidity affects treatment outcome in patients with anxiety. METHOD: Primary care patients with panic disorder (n=232), participating in a randomized collaborative care intervention of CBT and pharmacology, were divided into those above (n=125) and below (n=107) the median for burden of chronic medical illness and assessed at 3, 6, 9 and 12 months. RESULTS: Subjects with a greater burden of medical illness were more psychiatrically ill at baseline, with greater anxiety symptom severity, greater disability and more psychiatric comorbidity. The intervention produced significant and similar increases in amount of evidence-based care, and reductions in clinical symptoms and disability that were comparable in the more and less medically ill groups. CONCLUSIONS: The comparable response of individuals with more severe medical illness suggests that CBT and pharmacotherapy for panic disorder work equally well regardless of medical illness comorbidity. However, the more severe psychiatric illness both at baseline and follow-up in these same individuals suggest that treatment programs may need to be extended in time to optimize treatment outcome.  相似文献   
999.
Cognitive performance in untreated early onset gender identity disorder (GID) patients might correspond to their born sex and not to their perceived gender. As a current mode of intervention, cross-sex hormone treatment causes considerable physical changes in GID patients. We asked, as has been suggested, whether this treatment skews cognitive performance towards that of the acquired sex. Somatically healthy male and female early onset GID patients were neuropsychologically tested before, 3 and 12 months after initiating cross-sex hormone treatment, whereas untreated healthy subjects without GID served as controls (C). Performance was assessed by testing six cognitive abilities (perception, arithmetic, rotation, visualization, logic, and verbalization), and controlled for age, education, born sex, endocrine differences and treatment by means of repeated measures analysis of variance. GID patients and controls showed an identical time-dependent improvement in cognitive performance. The slopes were essentially parallel for males and females. There was no significant three-way interaction of born sex by group by time for the six investigated cognitive abilities. Only education and age significantly influenced this improvement. Despite the substantial somatic cross-sex changes in GID patients, no differential effect on cognition over time was found between C and GID participants. The cognitive performance of cross-sex hormone-treated GID patients was virtually identical to that of the control group. The documented test–retest effect should be taken into consideration when evaluating treatment effects generally in psychiatry.  相似文献   
1000.
Enteral nutrition support via a feeding tube is a preferred and broadly applied way of artificial nutrition in patients who cannot take up orally an adequate amount of nutrients. These patients often need simultaneous drug therapy as well. Thus, there is a high risk of drug-nutrient interactions. Although enteral nutrition is commonly used there is a lack of awareness and knowledge about the appropriate handling and drug administration via the feeding tube. On the one hand, drug-nutrient interactions can lead to clogging of the tube, on the other hand, the change in bioavailability of the drug can have a direct effect on the therapeutic effort. To optimise safety and efficacy of drug therapy in patients with feeding tubes, some basic rules have been set up.  相似文献   
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