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71.
Metabolic Brain Disease - Stroke is a lethal event with a high incidence in Egypt. Quick early intervention can be lifesaving. Transient global ischemia (TGI), a type of ischemic stroke, is mainly...  相似文献   
72.
73.
The hepatitis C virus (HCV) is a common blood-borne illness that affects up to 2% of the world’s population and almost 4 million Americans. Cognitive impairment, or difficulty with thinking, has become a well-established symptom in persons with end stage liver disease. It was previously assumed that cognitive impairment was a consequence of cirrhosis-associated hepatic encephalopathy. Recent evidence, however, suggests that approximately one-third of people with chronic HCV experience cognitive impairment even in the absence of cirrhosis and that its occurrence is unrelated to other indices of liver function, such as laboratory values, viral load, and genotype. In the present review, evidence outlining the presence of cognitive deficits associated with HCV, possible etiological factors, effects of antiviral therapy, and co-infection with human immunodeficiency virus (HIV) is presented. Implications of these findings and directions for future work are discussed.  相似文献   
74.
Twenty-one patients undergoing coronary artery bypass grafting were prospectively evaluated by conventional selective coronary angiography and electron-beam computed tomography. Eighty bypass grafts (60 saphenous vein and 20 left or right internal mammary artery) were evaluated for patency. The sensitivity and specificity of electron-beam computed tomography were 72% and 100%, respectively; positive and negative predictive values were 100% and 92.5%, respectively. Sensitivity and specificity according to coronary region were: left anterior descending artery, 33% and 100%; diagonal artery, 67% and 100%; circumflex artery, 75% and 100%; right coronary artery, 100% and 100%. Electron-beam computed tomography is relatively accurate and a promising tool for noninvasive evaluation of graft patency after coronary artery bypass graft surgery.  相似文献   
75.
The relationships among hemoglobin, ferritin, and transferrin receptor levels and 2 markers of human immunodeficiency virus (HIV) disease severity--HIV load and CD4(+) lymphocyte count--were characterized among 483 pregnant women in Malawi, Africa. The only significant correlation was an inverse correlation between hemoglobin level and plasma HIV load (r=-.104; P<.03). The prevalence of iron deficiency anemia was not significantly different across quartiles of HIV load or CD4(+) lymphocyte count. In contrast to previous studies, these data suggest that iron status is not related to markers of HIV disease severity in pregnant women in Africa.  相似文献   
76.
We report a 12-month old patient who presented for murmur evaluation after percutaneous closure of type C patent ductus arteriosus (PDA) using a 10 mm Amplatzer Vascular Plug (AGA Medical Corporation, Golden Valley, MN) at an outside institution. Echocardiography revealed a large left-to-right shunt through the implanted device, inadvertently stenting the PDA instead of closing it. The patient underwent repeat catheterization with successful coil implantation within the Amplatzer Vascular Plug, completely eliminating the large residual ductal shunt. Although challenging, this case illustrates the technique of implanting coils within this occlusion device. This case also illustrates that occlusion of type C PDA utilizing the Amplatzer Vascular Plug may not only result in incomplete occlusion but also create a potentially worse clinical situation in which the PDA is stretched larger and stented open. Without consideration of simultaneous coil implantation within this device, use of the Amplatzer Vascular Plug might be contraindicated in type C PDA, because there may be no way to ensure successful closure by the Vascular Plug alone.  相似文献   
77.
A series of new fluoroquinolone conjugates 8a–g and 9a–f were synthesized via benzotriazole‐mediated synthetic approach with good yield and purity. Some of the synthesized analogs exhibited significant antibacterial properties against Escherichia coli and Staphylococcus aureus with potency higher than that of the parent drugs through in vitro standard bioassay procedure (conjugates 8c and 8d reveal antimicrobial properties with potency 1.9, 61.9, 20.7 and 2.4, 37.1, 8.3 folds relative to the parent antibiotic 6 against E. coli, S. aureus, and Enterococcus faecalis, respectively). The observed experimental data were supported by enzymatic DNA gyrase inhibitory property. Developed BMLR‐QSAR model validates the observed experimental data and recognizes the parameters responsible for the enhanced antibacterial properties.  相似文献   
78.
Greater dispositional optimism has been related to less severe pain; however, whether optimism is associated with endogenous pain modulation has not yet been examined. The beneficial effects of dispositional optimism often vary according to cultural dynamics. Thus, assessing optimism–pain relationships across different ethnic groups is warranted. This study sought to examine the association between optimism and conditioned pain modulation (CPM), and test whether this association differs according to ethnicity. Optimism and CPM were assessed in a sample of healthy, ethnically diverse young adults. CPM was determined by comparing pressure pain thresholds obtained before and during exposure to a cold pressor task. All participants completed a validated measure of dispositional optimism. Greater reported optimism was significantly associated with enhanced CPM, and the strength of this association did not vary according to individuals’ ethnic background. These findings suggest that an optimistic disposition may potentiate endogenous pain inhibition.  相似文献   
79.
Hexanucleotide repeat expansions in C9ORF72 are a common cause of familial and apparently sporadic amyotrophic lateral sclerosis (ALS) and frontal temporal dementia (FTD). The mechanism by which expansions cause neurodegeneration is unknown, but current evidence supports both loss-of-function and gain-of-function mechanisms. We used pooled next-generation sequencing of the C9ORF72 gene in 389 ALS patients to look for traditional loss-of-function mutations. Although rare variants were identified, none were likely to be pathogenic, suggesting that mutations other than the repeat expansion are not a common cause of ALS, and providing supportive evidence for a gain-of-function mechanism. We also show by repeat-primed PCR genotyping that the C9ORF72 expansion frequency varies by geographical region within the United States, with an unexpectedly high frequency in the Mid-West. Finally we also show evidence of somatic instability of the expansion size by Southern blot, with the largest expansions occurring in brain tissue.  相似文献   
80.
The aim of this study performed in Normandy, France, was to analyze the pharyngeal meningococcal carriage at the peak of a clonal meningococcal B outbreak, which was subsequently controlled using an outer membrane vesicle vaccination. This cross-sectional study included randomly selected subjects aged 1–25 years. Carriers and non carriers were compared using unconditional logistic regression. Among the 3,522 volunteers, there were 196 (standardized rate: 6.46 %) Neisseria meningitidis carriers, of which there were only five with the outbreak strain (B:14:P1.7,16/ST-32; standardized rate: 0.18 %). From the multivariate analysis, older age, smoking, higher degree of socialization, and social deprivation appear to favor the carriage of all the strains included. Prior antibiotic treatment up to 12 months before swabbing, even with β-lactam, was protective against carriage. Our data indicate a low overall meningococcal carriage rate with a surprising protective effect of prior antibiotic exposure. The observed low carriage rate of the epidemic strain (B:14:P1.7,16/ST-32) contrasts with the high incidence of invasive meningococcal diseases (IMD) due to this strain. Hence, our data underline the high virulence of the strain and suggest a low level of natural immunity of the population against this strain. Although highly resource-consuming, carriage studies are helpful in guiding the implementation of control measures of IMD, such as mass vaccination or chemoprophylaxis.  相似文献   
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