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31.
Exposure to cigarette smoke is emerging as an environmental risk factor for multiple sclerosis (MS). We investigated the possible association between environmental tobacco smoke, its cumulative exposure, and MS risk. We used data from the Iranian Multiple Sclerosis Registry to identify a case-control of 662 patients who had MS and a comparison group of 394 patients. Information regarding current smoking status, including the number of cigarettes smoked per day, duration, and smoking pack-years indicative of cumulative dose of tobacco smoked was obtained. We analyzed the incidence of MS among ever–smokers who had been smokers during their disease course and prior to disease onset in comparison with never–smokers who had never been exposed by calculating the odds ratio (OR) with a 95% confidence interval (CI) employing logistic regression. Of the 662 MS patients, there were 523 women (79.0%) and 139 men (21.0%), with a mean age of 31 ± 10.0 years at disease onset. The risk for MS was increased among ever–smokers (OR = 1.78, 95% CI = 1.22–2.59, p = 0.03) compared to never–smokers. As compared with never smokers, the OR for patients with 6–10 pack years was 2.91 for men (95% CI = 1.11–9.47, p = 0.03) and 1.69 for women (95% CI = 1.02–6.45, p = 0.04). Our results demonstrate that cigarette smoking is significantly associated with an increased risk for MS. The risk effects of smoking were more noticeable in male patients and at higher tobacco doses.  相似文献   
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We aimed to assess the effects of concurrent cathodal transcranial direct current stimulation (c‐tDCS) of two targets in a hemisphere, termed unihemispheric concurrent dual‐site cathodal tDCS (c‐tDCSUHCDS), on the size of M1 corticospinal excitability and its lasting effect. Secondary aims were to identify the mechanisms behind the efficacy of c‐tDCSUHCDS and to evaluate the side effects of this new technique. Twelve healthy volunteers received 20 min c‐tDCS under five conditions in a random order: M1 c‐tDCS, c‐tDCSUHCDS of M1–dorsolateral prefrontal cortex (DLPFC), M1–primary sensory cortex (S1), M1–primary visual cortex (V1) and sham. The M1 corticospinal excitability of the first dorsal interossei muscle was assessed before, immediately after, and 30 min, 60 min and 24 h after the interventions. Short‐interval intracortical inhibition (SICI) and intracortical facilitation (ICF) were also assessed, using a paired‐pulse paradigm. Compared to conventional M1 c‐tDCS, corticospinal excitability significantly increased following c‐tDCSUHCDS of M1‐DLPFC and M1‐V1 for up to 24 h (P = 0.001). Significant increases in ICF were observed following c‐tDCSUHCDS of M1‐DLPFC (P = 0.005) and M1‐V1 (P = 0.002). Compared to baseline values, ICF and SICI increased significantly at T60 (P < 0.001) and T24 h (P < 0.001) following the concurrent c‐tDCS of M1 and V1. Sham c‐tDCSUHCDS did not induce any significant alteration. The corticospinal excitability increase was mainly accompanied by ICF increase, which indirectly indicates the activity of glutamergic mechanisms. The findings may help us to more fully understand the brain function and develop future motor learning studies. No significant excitability change induced by sham c‐tDCSUHCDS suggests that there is no placebo effect associated with this new tDCS technique.  相似文献   
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We aimed to compare the association of high-sensitivity C-reactive protein (CRP) and National Institutes of Health Stroke Scale (NIHSS) score with mortality risk and to determine the optimal threshold of CRP for prediction of mortality in ischemic-stroke patients. A series of 162 patients with first-ever ischemic-stroke admitted within 24 h after onset of symptoms was enrolled. CRP and NIHSS score were estimated on admission and their predictive abilities for mortality at 7 days were determined by logistic-regression analyses. Receiver-Operating Characteristic (ROC) curves were depicted to identify the optimal cut-off of CRP, using the maximum Youden-index and the shortest-distance methods. Deceased patients had higher levels of CRP and NIHSS on admission (8.87 ± 7.11 vs. 2.20 ± 4.71 mg/l for CRP, and 17.31 ± 6.36 vs. 8.70 ± 4.85 U for NIHSS, respectively, P < 0.01). CRP and NIHSS were correlated with each other (r 2 = 0.39, P < 0.001) and were also independently associated with increased risk of mortality [odds ratios (95 % confidence interval) of 1.16 (1.05–1.28) and 1.20 (1.07–1.35) for CRP and NIHSS, respectively, P < 0.01]. The areas under the ROC curves of CRP and NIHSS for mortality were 0.82 and 0.84, respectively. The CRP value of 2.2 mg/l was identified as the optimal cut-off value for prediction of mortality within 7 days (sensitivity: 0.81, specificity: 0.80). Thus, CRP as an independent predictor of mortality following ischemic-stroke is comparable with NIHSS and the value of 2.2 mg/l yields the optimum sensitivity and specificity for mortality prediction.  相似文献   
35.

Introduction

Misfolded tau and amyloid β (Aβ) proteins progressively accumulate in the human brain, causing altered neuronal function and neurodegeneration. This study sought to investigate whether the wide spectrum of functional reorganization in aging brains of cognitively normal individuals relates to specific pathological patterns of tau and Aβ deposits.

Methods

We used functional connectivity neuroimaging and in vivo tau and Aβ positron emission tomography scans to study cortical spatial relationships between imaging modalities.

Results

We found that a negative association between tau and functional connectivity combined with a positive association between Aβ and functional connectivity is the most frequent cortical pattern among elderly subjects. Moreover, we found specific brain areas that interrelate hypoconnectivity and hyperconnectivity regions.

Discussion

Our findings have critical implications to understanding how the two main elements of Alzheimer's disease–related pathology affect the aging brain and how they cause alterations in large-scale neuronal circuits.  相似文献   
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PURPOSE: To compare the frequency of canalicular stenosis as a side effect of weekly versus every-3-weeks docetaxel in patients with metastatic breast cancer. DESIGN: Retrospective nonrandomized comparative trial. PATIENTS AND METHODS: Eighteen patients enrolled in a phase II study of weekly docetaxel plus trastuzumab and 18 patients enrolled in a phase II study of every-3-weeks docetaxel plus doxorubicin were evaluated. Each patient underwent a comprehensive ophthalmologic examination, probing and irrigation of the nasolacrimal duct, and, in some instances, a nuclear lacrimal scan. MAIN OUTCOME MEASURES: If epiphora (excessive tearing) was reported by the patient, its time of onset was documented. In patients with epiphora, presence or absence of canalicular stenosis was evaluated on the basis of the findings on probing and irrigation. The duration of treatment with docetaxel, the dose frequency, and the cumulative dose of docetaxel were recorded in each case. RESULTS: Fourteen patients (77%) receiving weekly docetaxel plus trastuzumab had epiphora. Nine of these patients had significant anatomic narrowing of the canaliculi. Bicanalicular silicone intubation or dacryocystorhinostomy was recommended in all nine patients. Eight patients underwent surgery and experienced complete or near complete resolution of epiphora. Although two patients (11%) receiving every-3-weeks docetaxel plus doxorubicin reported transient symptoms of epiphora, neither patient was found to have narrowing of the canaliculi, and the epiphora was not severe enough to justify surgical intervention. The mean duration of docetaxel therapy for the patients in this study was 19 weeks. The mean cumulative dose of docetaxel was higher in patients with canalicular stenosis than in patients without this side effect. CONCLUSIONS: Canalicular stenosis was more common in patients receiving weekly docetaxel than in those receiving every-3-weeks docetaxel for metastatic breast cancer. Bicanalicular silicone intubation early in the course of weekly docetaxel therapy should be considered, because this intervention can prevent complete closure of the canaliculi. Once complete or near complete stenosis of the canaliculi occurs, placement of a permanent Pyrex glass tube may become necessary to overcome the blockage of tear outflow.  相似文献   
38.
BACKGROUND: Superficial wound dehiscence after midline sternotomy is considered a minor complication in cardiac surgery, although it is quite frequent and requires prolonged medical treatment. It can be managed conventionally by topical treatment, with delayed secondary healing, or by surgical treatment and primary skin closure. We report the outcome of 96 patients who underwent conventional treatment, compared with a second group of 42 patients who underwent surgical treatment and direct closure. METHODS: From October 1999 to December 2002, 2400 consecutive patients underwent median sternotomy: 207 patients had sternal wound complications: 3 patients (0.125%) had mediastinitis, 66 patients (2.75%) had aseptic deep sternal wound dehiscence, and 138 patients (5.75%) had superficial wound dehiscence. The latter are the object of the present study; patients entered a protocol of skin wound care on an outpatient basis. The first 96 consecutive patients (group 1) required medications three times a week until complete healing. The last 42 patients (group 2) were treated by extensive surgical debridement of skin and subcutaneous tissue, direct closure of the superficial layers, and suture removal after 15 days. RESULTS: The two groups were comparable as to age, sex, and preoperative risk factors. The incidence of contaminated wounds was similar in the two groups (32 of 96 in group 1 and 11 of 42 in group 2; p = NS). The length of treatment was 29.7 days (range 2 to 144 days) for group 1 and 12.2 days (range 2 to 37 days) for group 2 (p < 0.0001). The mean number of medical treatments was 9.4 per patient in group 1 and 3.7 per patient in group 2 (p < 0.0001). CONCLUSIONS: Surgical debridement and primary closure of superficial surgical wound dehiscence after median sternotomy is a safe and valid treatment. Wound infection is not a contraindication to surgical treatment. Primary closure may contribute to reduce the risk for later infection. It also definitely contributes to decreasing healing time and strongly lessens patients' discomfort, diminishing hospital costs and hospital staff workload.  相似文献   
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