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71.
We report the case of a 11-year-old girl who developed an isolated hand-writing disorder with dysgraphia at the beginning of the school year in the sixth grade. A brain magnetic resonance angiography showed a round arteriovenous malformation sited in the left side of the midbrain extending to the ipsilateral medio-basal thalamus. Child neurologists should never neglect a thorough neurological evaluation in case of isolated worsening of handwriting, to rule out possible underlying organic causes.  相似文献   
72.

Introduction

The Y-box binding protein-1 (YB-1) is a multifunctional oncoprotein involved in the proliferation and aggressiveness of cancer cells. The aim of this study was to determine whether strong YB-1 expression in neoplastic cells of colorectal liver metastases (CRLM) may have an impact on liver disease-free survival following liver resection.

Materials and Methods

Immunohistochemistry was performed to evaluate YB-1 in 66 patients who underwent liver resection for CRLM. YB-1 expression was classified as weak (low-staining intensity) and strong (high-staining intensity).

Results

YB-1 expression was observed in the cytoplasm of all CRLM. YB-1 expression was weak in 17 patients (25.8 %) and strong in 49 patients (74.2 %). Liver recurrence rate was significantly higher in the strong than in the weak expression group: 55.1 vs. 23.5 % (p?=?0.023). Multivariable logistic regression analysis showed that YB-1 strong expression was the only independent risk factor for liver recurrence. The 5-year specific liver disease-free survival rate was 76.0 % in the weak expression group and 41.5 % in the strong expression group (p?=?0.034). These results were not influenced by clinical prognostic factors of tumor recurrence.

Conclusions

This is the first study showing that the degree of YB-1 expression in tissue specimens of CRLM predicts liver recurrence following liver resection.  相似文献   
73.

Rationale

Neuronal nicotinic acetylcholine receptors (nAChRs) play a modulatory role in cognition, and zebrafish provide a preclinical model to study learning and memory.

Objectives

We investigated the effect of nicotine (NIC) and some new cytisine-derived partial agonists (CC4 and CC26) on spatial memory in zebrafish using a rapid assay on T-maze task. The role of α4/α6β2 and the α7 nAChRs in NIC-induced memory enhancement was evaluated using selective nAChR antagonists.

Results

Low and high doses of NIC, cytisine (CYT), CC4 and CC26 respectively improved and worsened the mean running time, showing an inverted U dose–response function. The effective dose (ED50) (×10?5 mg/kg) was 0.4 for CC4, 4.5 for CYT, 140 for NIC and 200 for CC26. NIC-induced cognitive enhancement was reduced by the selective nAChR subtype antagonists: methyllycaconitine (MLA) for α7, α-conotoxin (MII) for α6β2, dihydro-β-erythroidine (DhβE) for α4β2, the nonselective antagonist mecamylamine (MEC) and the muscarinic antagonist scopolamine (SCOP), with DhβE being more active than MLA or MII. All the partial agonists blocked the cognitive enhancement. The improvement with the maximal active dose of each partial agonist was blocked by low doses of DhβE (0.001 mg/kg) and MII (0.01 mg/kg). MLA reduced the effects of CC26 and CC4 at doses of 0.01 and 1 mg/kg, respectively, but did not antagonize CYT-induced memory improvement at any of the tested dose. No change in swimming activity was observed.

Conclusions

Our findings demonstrate that zebrafish make a useful model for the rapid screening of the effect of new α4β2 nAChR compounds on spatial memory.  相似文献   
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76.
At present surgery is accepted as the most effective mode of therapy for carcinoma of the lung. Because the lack of respiratory reserve is the major determinant of postoperative function, it is useful to identify the patient, who is at significant risk. Eighteen patients with lung cancer (mean age = 56 +/- 6.5 years) were studied preoperatively (preop) and postoperative (postop) (three to four months after lung resection) by spirometry, measurement of arterial blood gases, and quantitative lung scanning (99mTc). A predicted postoperative value of some variables was calculated by the formula: postop value = preop value x % function of regions of lung not resected. The correlation coefficient between the predicted (pred) and postoperatively observed (observ) values VC = vital capacity, FEV1 = forced expiratory volume in 1 second) is: VC pred/VC observ r = 0.83 p less than 0.001 FEV1 pred/FEV1 observ r = 0.82 p less than 0.001. The authors' results agree with earlier reports and show that the method used can accurately predict the postoperative respiratory function in patients undergoing lung resection (pneumonectomy or lobectomy). A predicted FEV1 of 0.8 L does not permit a surgical program, because, below this level, carbon dioxide retention becomes more frequent and exercise intolerance is increasingly severe (poor quality of life). The method proposed to predict the postoperative respiratory function is simple and routinely useful. The authors choose a perfusion instead of ventilation scan, because the former provides similar predicted postoperative data, and can be done routinely.  相似文献   
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79.

Objective

High on-treatment platelet reactivity (HPR) is a well-known risk factor for adverse events in patients undergoing percutaneous coronary intervention (PCI). However, whether reducing platelet reactivity can lead to a lower incidence of ischemic events after PCI is still controversial. Therefore, we sought to investigate this issue by a meta-regression analysis of randomized trials.

Methods

We collected randomized trials reporting HPR rates in patients receiving different antiplatelet therapies. ΔHPR was defined as the difference between HPR rates achieved in control vs. experimental arms, and the relationship between ΔHPR and clinical outcomes was evaluated.

Results

Thirty trials totalling 6683 patients with a mean follow-up of 3-month were included. Reducing platelet reactivity was associated to a decreased risk of major adverse cardiac events (MACE), with a linear relationship between ΔHPR and MACE (change in tau2 = −2.50; p = 0.023). Particularly, achieving a 10% difference in HPR rates resulted in a parallel risk reduction in MACE of about 11% (Exp(b) = 0.98; 95% CI, 0.97–0.99).Changes in HPR predict the risk of ischemic events in patients with acute coronary syndrome (change in tau2 = −2.52; Exp(b) = 0.98; 95% CI, 0.97–0.99; p = 0.03), but not in patients with poor response to clopidogrel (change in tau2 = −1.44; Exp(b) = 0.98; 95% CI, 0.96–1.01; p = 0.19) or stable coronary artery disease (change in tau2 = −0.14; Exp(b) = 0.99; 95% CI, 0.94–1.05; p = 0.89).

Conclusion

Reducing HPR occurrence decreases the risk of ischemic events in patients with acute coronary syndrome undergoing PCI, whereas a strategy of reducing platelet reactivity does not improve clinical outcomes in patients with poor response to clopidogrel or stable coronary artery disease.  相似文献   
80.
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