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81.
Neurobehavioral Deficits Consistent Across Age and Sex in Youth with Prenatal Alcohol Exposure 下载免费PDF全文
82.
Malaria exacerbates inflammation‐associated elevation in ferritin and soluble transferrin receptor with only modest effects on iron deficiency and iron deficiency anaemia among rural Zambian children 下载免费PDF全文
83.
Many people believe that euthanasia and assisted suicide are condoned carte blanche in the Netherlands. Not true. Both are formally forbidden by criminal law and can be administered only when certain procedures and criteria have been followed. Below, a look at the policies and practices regarding euthanasia and assisted suicide in The Netherlands and the role of nurses in this area. 相似文献
84.
Role of T and NK cells and IL7/IL7r interactions during neonatal maturation of lymph nodes 下载免费PDF全文
Coles MC Veiga-Fernandes H Foster KE Norton T Pagakis SN Seddon B Kioussis D 《Proceedings of the National Academy of Sciences of the United States of America》2006,103(36):13457-13462
Lymph node (LN) development depends on prenatal interactions occurring between LN inducer and LN organizer cells. We have distinguished defects in LN formation due to failure in embryonic development (aly/aly) from defects in postnatal maturation (Il2rgamma(-/-)Rag2(-/-)). Both mutant strains form normal primordial LNs with differing fate. In aly/aly mice, the LN primordium dissipates irreversibly late in gestation; in contrast, Il2rgamma(-/-)Rag2(-/-) LN anlage persists for a week after birth but disperses subsequently, a process reversible by neonatal transfer of WT IL7r(+) TCR(+) T or natural killer (NK) cells, suggesting a role for IL7/IL7r interactions. Thus, we reveal a unique stage of postnatal LN development during which mature lymphocytes and IL7/IL7r interactions may play an important role. 相似文献
85.
Howell KK Lynch ME Platzman KA Smith GH Coles CD 《Journal of pediatric psychology》2006,31(1):116-126
BACKGROUND: Prenatal alcohol exposure is associated with learning, behavioral, and academic problems even in children without the fetal alcohol syndrome (FAS). OBJECTIVE: To examine the prenatal alcohol exposure and ability, academic achievement, and school functioning in adolescence. METHODS: In a longitudinal cohort, intelligence, academic performance, and school functioning were evaluated in 265 low socioeconomic status (SES) adolescents (M age = 15.1 years), 128 prenatally exposed to alcohol, 53 controls, and 84 special education students by using the Wechsler Intelligence Scale for Children, 3rd edition (WISC-III) and the Wechsler Individual Achievement Test (WIAT). School records were abstracted for grade point averages (GPA), standardized achievement test scores, conduct, attendance, and special education placement. RESULTS: Alcohol-affected youth had significantly lower IQs than those in the other three groups. CONCLUSION: Although academic achievement (WIAT scores) was most impaired in the special education group who showed lower performance over all as well as in reading and spelling, alcohol-affected youth showed significant deficits on mathematics subtests. There was no increased incidence of conduct problems in school records related to alcohol exposure. 相似文献
86.
Symptomatic peripheral arterial disease: the value of a validated questionnaire and a clinical decision rule 下载免费PDF全文
Bianca LW Bendermacher Joep AW Teijink Edith M Willigendael Marie-Louise Bartelink Harry R Büller Ron JG Peters Jelis Boiten Machteld Langenberg Martin H Prins 《The British journal of general practice》2006,56(533):932-937
BACKGROUND: If a validated questionnaire, when applied to patients reporting with symptoms of intermittent claudication, could adequately discriminate between those with and without peripheral arterial disease, GPs could avoid the diagnostic measurement of the ankle brachial index. AIM: To investigate the Edinburgh Claudication Questionnaire (ECQ) in general practice and to develop a clinical decision rule based on risk factors to enable GPs to easily assess the likelihood of peripheral arterial disease. DESIGN OF STUDY: An observational study. SETTING: General practice in The Netherlands. METHOD: This observational study included patients of > or =55 years visiting their GP for symptoms suggestive of intermittent claudication or with one risk factor. The ECQ and the ankle brachial index were performed. The prevalence of peripheral arterial disease, defined as an ankle brachial index <0.9, was related to risk factors using logistic regression analyses, on which a clinical decision rule was developed and related to the presence of peripheral arterial disease. RESULTS: Of the 4790 included patients visiting their GP with symptoms suggestive of intermittent claudication, 4527 were eligible for analyses. The prevalence of peripheral arterial disease in this group was 48.3%. The sensitivity of the ECQ was only 56.2%. The prevalence of peripheral arterial disease in a clinical decision rule that included age, male sex, smoking, hypertension, hypercholesterolemia, and a positive ECQ, increased from 14% in the lowest to 76% in the highest category. CONCLUSION: This study indicates that the ECQ alone has an inadequate diagnostic value in detecting patients with peripheral arterial disease. The ankle brachial index should be performed to diagnose peripheral arterial disease in patients with complaints suggestive of intermittent claudication, although our clinical decision rule could help to differentiate between extremely high and lower prevalence of peripheral arterial disease. 相似文献
87.
Maarten E Witte Lars B Richard J Rodenburg Jeroen A Belien Rene Musters Thierry Hazes Liesbeth T Wintjes Jan A Smeitink Jeroen JG Geurts Helga E De Vries Paul van der Valk Jack van Horssen 《The Journal of pathology》2009,219(2):193-204
Mitochondrial dysfunction has been implicated in the development and progression of multiple sclerosis (MS) lesions. Mitochondrial alterations might occur as a response to demyelination and inflammation, since demyelination leads to an increased energy demand in axons and could thereby affect the number, distribution and activity of mitochondria. We have studied the expression of mitochondrial proteins and mitochondrial enzyme activity in active demyelinating and chronic inactive MS lesions. Mitochondrial protein expression and enzyme activity in active and chronic inactive MS lesions was investigated using (immuno)histochemical and biochemical techniques. The number of mitochondria and their co‐localization with axons and astrocytes within MS lesions and adjacent normal‐appearing white matter (NAWM) was quantitatively assessed. In both active and inactive lesions we observed an increase in mitochondrial protein expression as well as a significant increase in the number of mitochondria. Mitochondrial density in axons and astrocytes was significantly enhanced in active lesions compared to adjacent NAWM, whereas a trend was observed in inactive lesions. Complex IV activity was strikingly up‐regulated in MS lesions compared to control white matter and, to a lesser extent, NAWM. Finally, we demonstrated increased immunoreactivity of the mitochondrial stress protein mtHSP70 in MS lesions, particularly in astrocytes and axons. Our data indicate the occurrence of severe mitochondrial alterations in MS lesions, which coincides with enhanced mitochondrial oxidative stress. Together, these findings support a mechanism whereby enhanced density of mitochondria in MS lesions might contribute to the formation of free radicals and subsequent tissue damage. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
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90.
MacQuarrie RA Fang Chen Y Coles C Anderson GI 《Journal of biomedical materials research. Part B, Applied biomaterials》2004,69(1):104-112
Periprosthetic osteolysis involves osteoclast activation by wear particulates and their exposure to mechanical perturbation through exposure to shear forces generated by periprosthetic fluid as well as interface micromotion. This study aimed to determine the interactions between wear particulates, mechanical stimulation, and osteoclasts. In static cultures, wear particulates increased osteoclast differentiation. Addition of neutralizing antibodies to RANKL (receptor activator of nuclear factor kappa ligand) inhibited the particle-induced increase in osteoclast numbers. Cyclic 5000 microstrains were applied with the use of a custom-built device to marrow-derived cultures to assess the effect on osteoclast differentiation. Mechanical strain application alone decreased osteoclast differentiation, which was further decreased by the addition of particles despite increases in the soluble RANKL to osteoprotegerin (OPG) ratio. Mechanical strain alone induced mature osteoclast apoptosis in a dose-dependent manner. In contrast, in the mature osteoclast model, the addition of nonmetal particulates protected the osteoclasts from becoming apoptopic. Titanium (Ti) and cobalt chromium (CoCr) particles, however, induced osteoclast apoptosis, whereas polyethylene (PE) and polymethylmethacrylate (PMMA) did not. Wear particulates and mechanical stimulation interact via an eicosanoid-dependent pathway to alter osteoclast function and survival. The addition of mechanical perturbation to a particle-laden system thus appears to enhance the potential for osteolytic activity by enhancing osteoclast survival. 相似文献