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151.
Van Camp N Peeters RR Van der Linden A 《Journal of magnetic resonance imaging : JMRI》2005,22(4):483-491
PURPOSE: To implement and optimize cerebral blood volume (CBV)-weighted functional magnetic resonance imaging (fMRI) in the rat cerebral and cerebellar cortex during electrical paw stimulation. MATERIALS AND METHODS: fMRI of the cerebral and cerebellar cortex was performed during electrical paw stimulation on a 7-T MRI system (MRRS, Guilford, UK) comparing the blood oxygenation level-dependent (BOLD) and CBV-weighted contrast with different ultrasmall particles of iron oxide (USPIO) contrast doses (NC100150, 30 mg Fe/mL; Amersham Health, Oslo, Norway) and different TE. RESULTS: Doses of 15 and 20 mg/kg USPIO at TE = T*2 or TE = 14 msec almost doubled the contrast-to-noise ratio (CNR) of the activated areas in the cerebral cortex without affecting the overall signal-to-noise ratio (SNR) or the incidence of activation (100%). In the cerebellum the SNR decreased significantly with an increasing contrast dose. At a dose of 15 mg/kg, the CNR was slightly smaller than the CNR measured in the BOLD images, but the activation incidence seemed to be doubled. At 20 mg/kg, the CNR was slightly increased, but the activation incidence was lower. At both contrast doses the venous artifacts disappeared. CONCLUSION: A USPIO contrast dose of 20 mg/kg proved to be beneficial for fMRI in the rat, even though it affected the CNR and SNR in the cerebral and the cerebellar cortex differentially. 相似文献
152.
Patients presenting with atherosclerosis of the extracranial carotid arteries may be offered carotid endarterectomy (CEA), carotid artery stenting (CAS), or medical therapy to reduce their risk of stroke. In many cases, the choice between treatment modalities remains controversial. An algorithm based on patients' neurologic symptoms, comorbidities, limiting factors for CAS and CEA, and personal preferences was developed to determine the optimal treatment in each case. This algorithm was then employed to determine therapy in 308 consecutive patients presenting to a single institution during one calendar year. Ninety-five (30.8%) patients presented with an asymptomatic carotid stenosis of more than 80% and 213 (69.2%) with a symptomatic stenosis of more than 50%. According to our algorithm, 59 (62.1%) of the 95 asymptomatic patients received CAS, 20 (21.1%) received CEA, and 16 (16.8%) received medical therapy. All symptomatic patients underwent intervention; 153 (71.8%) were treated with CAS and 60 (28.2%) with CEA. Combined 30-day stroke and death rates after CAS were 1.7% in asymptomatic patients and 2.6% in symptomatic patients. After CEA, these rates were 0% and 3.3%, respectively. Careful selection of treatment modality according to predetermined criteria can result in improved outcomes. 相似文献
153.
Age at menarche in relation to adult height: the EPIC study 总被引:4,自引:0,他引:4
Onland-Moret NC Peeters PH van Gils CH Clavel-Chapelon F Key T Tjønneland A Trichopoulou A Kaaks R Manjer J Panico S Palli D Tehard B Stoikidou M Bueno-De-Mesquita HB Boeing H Overvad K Lenner P Quirós JR Chirlaque MD Miller AB Khaw KT Riboli E 《American journal of epidemiology》2005,162(7):623-632
In the last two centuries, age at menarche has decreased in several European populations, whereas adult height has increased. It is unclear whether these trends have ceased in recent years or how age at menarche and height are related in individuals. In this study, the authors first investigated trends in age at menarche and adult height among 286,205 women from nine European countries by computing the mean age at menarche and height in 5-year birth cohorts, adjusted for differences in socioeconomic status. Second, the relation between age at menarche and height was estimated by linear regression models, adjusted for age at enrollment between 1992 and 1998 and socioeconomic status. Mean age at menarche decreased by 44 days per 5-year birth cohort (beta = -0.12, standard error = 0.002), varying from 18 days in the United Kingdom to 58 days in Spain and Germany. Women grew 0.29 cm taller per 5-year birth cohort (standard error = 0.007), varying from 0.42 cm in Italy to 0.98 cm in Denmark. Furthermore, women grew approximately 0.31 cm taller when menarche occurred 1 year later (range by country: 0.13-0.50 cm). Based on time trends, more recent birth cohorts have their menarche earlier and grow taller. However, women with earlier menarche reach a shorter adult height compared with women who have menarche at a later age. 相似文献
154.
de Buck PD le Cessie S van den Hout WB Peeters AJ Ronday HK Westedt ML Breedveld FC Vliet Vlieland TP 《Arthritis and rheumatism》2005,53(5):682-690
OBJECTIVE: Work disability is a major consequence of inflammatory rheumatic conditions. Evidence regarding the effectiveness of interventions aimed at the prevention or reduction of work disability in rheumatic diseases is limited. We conducted a randomized controlled trial to investigate the effectiveness of a multidisciplinary job-retention vocational rehabilitation (VR) program in patients with a rheumatic condition who were at risk for job loss. METHODS: A total of 140 patients with a chronic rheumatic condition were randomly assigned to either a multidisciplinary job-retention VR program (n = 74) or usual outpatient care (UC) (n = 66). Patients in the VR group were assessed and guided by a multidisciplinary team, whereas patients in the UC group received care as initiated by their rheumatologist, supplemented with written information. The main outcome measure was the occurrence of job loss (complete work disability or unemployment); additional outcome measures included job satisfaction, pain, functional status, emotional status, and quality of life. RESULTS: There was no difference between the 2 groups regarding the proportion of patients having lost their job at any time point, with 24% and 23% of the patients in the VR and UC groups, respectively, having lost their job after 24 months. Over the total period of 24 months, patients in the VR group had a significantly greater improvement of the fatigue visual analog scale and of emotional status (all P values < 0.05). CONCLUSION: A job-retention VR program did not reduce the risk of job loss but improved fatigue and mental health in patients with chronic rheumatic diseases at risk for job loss. 相似文献
155.
156.
H. J. F. Peeters P. Van Heerde Th. M. Feltkamp-Vroom 《Documenta ophthalmologica. Advances in ophthalmology》1982,52(2):387-391
Space-filling lesions in the orbit can be divided into 3 large groups: 1. Acute and subacute inflammatory processes (bacterial, fungal, parasitic, foreign body). 2. Benign and malignant tumours, true new growths. 3. Pseudo-tumours. The conditions in group 3 are also space-filling lesions, but have the characteristics of a chronic, infiltrating, inflammatory process. In 11% of 340 consecutive patients in the Orbital Centre in Amsterdam this diagnosis was made. The group is far from uniform: the dominant cell type varies from one case to another. Usually lymphocytic cells are dominant; if these are arranged in follicles the lesion is called a pseudo-lymphoma. This condition can gradually leave the province of the pseudo-tumours and begin to show the characteristics of a malignant or non-Hodgkin lymphoma. Sometimes the inflammatory character of the lymphoid infiltration is dominant, as in myositis, sclerotenonitis and infiltrative Graves' ophthalmophathy; these conditions are clearly related to immunological processes.Attempts to classify all pseudo-tumours on a pathological basis have remained rather vague.Clinical picture: rapid development (2–6 months); pain and oedema are present, but these are not the principal symptoms; secondary features are: disorders of motility, visual loss and other symptoms. Bilaterality usually indicates the presence of a systemic disease.Therapy: the possibilities are treatment of the infection, corticosteriods, chemotherapy, radiotherapy and surgery. 相似文献
157.
A test situation was developed in which the effects of drugs on habituation of exploratory behavior (head-poke responses) could be assessed independently of their effects on general activity (locomotion and rearing). Habituation, spontaneous recovery from habituation and stimulus specificity of habituation were studied.An amphetamine-barbiturate mixture attenuated habituation of the head-poke response without influencing general activity. Pro-Leu-Gly-NH2 (PLG), an oxytocin fragment, increased locomotor activity and did not alter the course of habituation of the head-poke response. Since exploratory behavior and general activity can be pharmacologically dissociated in the test situation used, it is concluded that the test situation is suitable for studying the effects of drugs on habituation of exploratory behavior. The amphetamine-barbiturate mixture did not influence the stimulus specificity of habituation of the head-poke response. Fenfluramine however increased the effects of stimulus change on the head-poke response while not influencing habituation of this response. These results show that habituation and stimulus specificity of habituation of exploratory behavior can be pharmacologically dissociated. 相似文献
158.
Spaanderman ME Willekes C Hoeks AP Ekhart TH Aardenburg R Courtar DA Van Eijndhoven HW Peeters LL 《American journal of obstetrics and gynecology》2005,192(2):504-512
OBJECTIVE: Evidence is accumulating that fetal growth is influenced by preexisting maternal disorder(s) hampering endothelial function. We tested the hypothesis that in nonpregnant normotensive, formerly preeclamptic women, vascular function predicts the development of fetal growth restriction. METHODS: In 60 formerly preeclamptic women, we measured central hemodynamic and vascular and clotting function mid follicular phase during the menstrual cycle. Inclusion for final analysis required besides normotension, a subsequent singleton pregnancy, established within 1 year after the prepregnant evaluation and ongoing beyond 16 weeks' gestation. In the ongoing pregnancy we determined birth weight and birth weight percentile. RESULTS: Among 60 formerly preeclamptic women, 45 (75%) were normotensive. Thirty-one (69%) participants succeeded in establishing an ongoing pregnancy within 1 year and were included for final analysis. Of the 31 subsequent pregnancies, 8 (26%) were complicated by fetal growth restriction. Prepregnant left and right uterine artery pulsatility index (PI) correlated inversely with carotid artery compliance ( r = 0.57, P = .005, r = 0.62, P = .002) and venous compliance ( r = 0.49, P = .02 and r = 0.45, P = .04, respectively). The latter, in turn, correlates with plasma volume ( r = 0.63, P = .001) and total peripheral vascular resistance index ( r = -0.45, P = .02). Finally, prepregnant left and right uterine artery PI correlated inversely with subsequent achieved fetal growth ( r = -0.68, P < .0001 and r = -0.58, P = .001, respectively). CONCLUSION: In nonpregnant normotensive, formerly preeclamptic women, an elevated uterine artery PI predisposes to subsequent restriction in fetal growth. 相似文献
159.
Toni T Adjé-Touré C Vidal N Minga A Huet C Borger MY Recordon-Pinson P Masquelier B Nolan M Nkengasong J Fleury HJ Delaporte E Peeters M 《AIDS research and human retroviruses》2005,21(7):667-672
Based on partial env and pol (protease and RT) subtyping, we recently documented that the majority (>80%) of the HIV-1 strains that circulate in C?te d'Ivoire were CRF02_AG and about 11% were recombinants or could not be clearly assigned to a known subtype or CRF. In order to determine in more detail the precise structure of these viruses we sequenced the full-length genomes for six such strains. Bootscan and phylogenetic tree analysis showed that four strains were complex and unique CRF02_AG/CRF09_cpx recombinants, one was a CRF02_AG/CRF06_cpx recombinant, and one was a pure CRF09_cpx. Reanalysis of the remaining recombinants asserted the predominance of CRF09_cpx within intersubtype recombinants and circulation of CRF09_cpx in C?te d'Ivoire. More detailed analysis of the CRF09_cpx strains revealed also that part of the pol gene belonged to subtype K. This is the first time that such recombinants are described. 相似文献
160.
In aphasia due to stroke, language-related activity shifts not only to undamaged cortex within the dominant hemisphere but also toward right-sided areas homotopical to the left-sided lesion. We examined whether a rightward shift takes place in primary progressive aphasia (PPA). Nineteen PPA patients participated, 19 healthy subjects and 14 patients with amnestic mild cognitive impairment who served as controls. Subjects underwent neuropsychological assessment, structural magnetic resonance imaging (MRI), and a functional MRI with a factorial design: words versus pictures and associative-semantic versus visuoperceptual task. Measures of neuropsychological performance were entered as regressors into a multiple linear regression analysis, with response amplitude during the associative-semantic versus control conditions as outcome variable. Language competence correlated negatively with responses in the right anterior temporal cortex and positively with volume and responses in the left-sided homotope. In normal subjects, anterior temporal activation was more extensive to the left than the right (laterality index [LI], +0.64; standard error [SE], 0.11). Laterality was inverted in PPA with word comprehension deficit (LI, - 0.34; SE, 0.19), with an intermediate pattern in PPA without comprehension deficit (LI, +0.23; SE, 0.14). The rightward laterality shift previously reported in aphasic stroke extends to PPA, in particular, when comprehension is deficient. 相似文献