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The question of whether i.v. rt-PA is beneficial in patients with ischaemic stroke and atrial fibrillation (AF) remains unresolved. Our objective was to evaluate the outcome of patients with AF who received i.v. rt-PA for stroke in the registries of Lille (France) and Belgrade (Serbia). End-points were poor outcome [modified Rankin Scale (mRS) 3–6], and symptomatic haemorrhagic transformation (sHT) according to ECASS3. Of 734 consecutive patients, 155 (21.2 %) had AF. The unadjusted comparison found patients with AF to be 12 years older, more likely to be women, to have hypertension, and baseline INR > 1.2, and less likely to be smokers. They had higher baseline NIHSS scores, diastolic blood pressure, and serum glucose concentrations, and lower platelet counts. They did not differ for sHT (5.8 vs. 5.5 %; p = 0.893), but they more frequently had poor outcomes (52.3 vs. 35.2 %; p < 0.001) and death (21.9 vs. 9.0 %; p < 0.001). The only independent predictor of sHT was baseline NIHSS (adjOR 1.05 per 1 point increase; 95 % CI 1.01–1.10). Independent variables associated with poor outcome were age (adjOR 1.04 for 1 year increase; 95 % CI 1.03–1.06), baseline NIHSS (adjOR 1.17 per 1 point increase; 95 % CI 1.13–1.21), and sHT (adjOR 47.6; 95 % CI 10.2–250) but not AF. In patients treated with i.v. rt-PA for cerebral ischaemia, those with AF have worse outcomes because they are older and have more severe strokes at admission. This result suggests that we should focus on prevention and research of more aggressive strategies at the acute stage.  相似文献   
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Catechol-O-methyltransferase (COMT) plays an important role in the catabolism of brain dopamine and norepinephrine, which have been implicated in the pathogenesis of Autism spectrum disorder (ASD) as well as in other neuropsychatric disorders. We aimed to investigate the association of COMT Val158Met gene polymorphism with ASD and to examine the influence of such genotypes on hyperactivity symptoms in ASD patients. Eighty ASD patients (mean age 9 ± 1.9 years) and 100 control children (mean age 8.9 ± 1.9 years) were examined. COMT Val58Met polymorphism was genotyped using Tetra-primer ARMS-PCR method. The clinical diagnosis of ASD and ADHD were confirmed according to the DSM-IV criteria for research. We found no significant difference in genotypes or alleles’ frequencies of COMT Val158Met polymorphism between ASD patients and control group. There was a significant association between COMT (Val/Val) genotype and both increasing CARS (p = 0.001) and hyperactivity scores (p = 0.006). Regarding Conner's Score, the DSM-IV hyperactive impulsive were significantly higher in Val/Val genotype than both Met/Val and Met/Met genotypes (p = 0.03). Our data suggested an association between COMT Val58Met polymorphism and hyperactivity symptoms in Egyptian children with ASD.  相似文献   
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The malaria parasite sporozoite stage develops in the mosquito vector and is transmitted to the mammalian host by bite. Sporozoites engage in multiple interactions with vector and host tissue on the journey from their oocyst origin to their final destination inside hepatocytes. Several malaria proteins have been identified that mediate sporozoite interactions with target tissues such as secreted and surface-associated ligands CSP and TRAP, which contain a thrombospondin type 1 repeat (TSR). Recently, we identified thrombospondin-related sporozoite protein (TRSP) in Plasmodium sporozoites, which exhibits a single TSR in its putative extracellular N-terminal region and is highly conserved among Plasmodium species. Here, we show using targeted gene disruption in the rodent malaria model Plasmodium berghei, that lack of TRSP has no effect on the asexual blood stage cycle, parasite transmission to the mosquito, sporozoite development and infection of mosquito salivary glands. However, analysis of TRSP knockout sporozoites in vitro and in vivo indicates that this protein has a significant role in hepatocyte entry and therefore liver infection. Thus, TRSP is an additional TSR-containing malaria parasite protein that is mainly involved in initial infection of the mammalian host.  相似文献   
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Two commonly used whole breast irradiation (WBI) techniques, deep inspiration breath hold (DIBH) and prone positioning, are compared with regard to dosimetry and estimated late cardiac morbidity and secondary lung cancer mortality using published models. Forty patients with left‐sided DCIS or breast cancer who underwent lumpectomy and required adjuvant WBI were enrolled on a prospective trial comparing supine DIBH (S‐DIBH) with prone free breathing (P‐FB) planning. Patients underwent CT simulation in both positions; two plans were generated for each patient. Comparative dosimetry was available for 34 patients. Mean cardiac and lung doses were calculated. Risk of death from ischemic heart disease (IHD), risk of at least one acute coronary event (ACE), and lung cancer mortality were estimated from published data. Difference between S‐DIBH and P‐FB plans was compared using paired two‐tailed t test. Estimated mean risk of death from IHD by age 80 was 0.1% (range 0.0%‐0.2%) for both plans (P = 1.0). Mean risk of at least one ACE was 0.3% (range 0.1%‐0.6%) for both plans (P = .6). Mean lung cancer mortality risk was 1.4% (range 0.5%‐15.4%) for S‐DIBH and 1.0% (range 0.4%‐9.8%) for P‐FB (P = .008). Excess lung cancer mortality due to radiation was 0.5% (range 0.1%‐6.0%) with S‐DIBH and 0.0% (range 0.0%‐0.4%) with P‐FB (P = .008). Both S‐DIBH and P‐FB provide excellent cardiac sparing. Prone positioning results in lower lung dose than S‐DIBH and leads to an absolute decrease of 0.5% in excess lung cancer mortality for patients receiving WBI.  相似文献   
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