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101.
Neuropathological abnormalities of the corpus callosum in schizophrenia: a diffusion tensor imaging study 总被引:29,自引:0,他引:29
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Foong J Maier M Clark CA Barker GJ Miller DH Ron MA 《Journal of neurology, neurosurgery, and psychiatry》2000,68(2):242-244
OBJECTIVES: Diffusion tensor imaging (DTI), a technique capable of examining water diffusion in different tissues and the organisation of white matter tracts, was used to investigate the neuropathology of the corpus callosum in vivo in patients with schizophrenia. METHODS: Diffusion tensor imaging was performed in 20 schizophrenic patients and 25 healthy controls. Two complementary measures, mean diffusivity and fractional anisotropy, which are considered to be sensitive indices of axonal integrity, were obtained from regions of interest in the genu (anterior) and splenium (posterior) of the corpus callosum. RESULTS: Mean diffusivity was significantly increased and fractional anisotropy significantly reduced in the splenium but not the genu of the corpus callosum in the schizophrenic group compared with controls. There were no significant sex differences in the DTI measures for either the schizophrenic or control group. Clinical variables such as age, duration of illness, dose of antipsychotic medication, and schizophrenic symptoms did not predict the DTI changes in the schizophrenic patients. CONCLUSIONS: The presence of DTI changes in the splenium but not the genu of the corpus callosum suggests that there may be a focal disruption of commisural connectivity in schizophrenia. However, these findings do not exclude the possibility of abnormalities in other areas of the corpus callosum or other regions of white matter and further research using different methods of analysis may enable us to clarify this. Diffusion tensor imaging is a valuable tool in investigating the structure of white matter in schizophrenia. 相似文献
102.
Maier AG Kersting-Sommerhoff B Reeders JW Judmaier W Schima W Annweiler AA Meusel M Wallengren NO 《Journal of magnetic resonance imaging : JMRI》2000,12(5):651-660
The aim of this study was to assess the accuracy of double-contrast magnetic resonance imaging (MRI) with rectal application of the superparamagnetic iron oxide contrast agent (SPIO) ferristene and IV gadodiamide for preoperative staging of rectal cancer. In a randomized phase II dose-ranging trial, 113 patients were studied preoperatively with one of four different formulations of ferristene (Abdoscan) as an enema before MRI. T1-weighted spin-echo (T1w SE) and T2w turbo spin-echo (TSE) single-contrast images were obtained as well as T1w SE and gradient-echo (GRE) double-contrast images after IV gadodiamide injection (Omniscan). Images were assessed qualitatively, and TNM tumor stage was compared with histopathology. High-viscosity ferristene formulations were superior to low-viscosity formulations in tumor staging (accuracy 90% vs 74%, P < 0.01). There was no significant difference between high and low iron content ferristene. MRI had a sensitivity of 97%, specificity of 50%, and accuracy of 82% for staging of rectal carcinoma higher than T2 stage. At receiver operator characteristic (ROC) analysis, MR differentiation between T1/T2 and T3/T4 tumor stages yielded a ROC index of 0.848. Double-contrast MRI is an accurate method for preoperative staging of rectal cancer. 相似文献
103.
Between 1980 and 1989, reports on 2,165 fractures of the distal part of the femur (1,051 women and 1,114 men) were collected by AO Documentation and are analyzed in the present paper. The number of fractures showed a bimodal pattern with a marked variation in the number of fractures in relation to gender and age. A larger prevalence of fractures was observed either in young men (about 20 years old, traffic or sport) and in old women (about 70, fall at home, osteoporosis). 相似文献
104.
Michael Wagner Boris B Quednow Jens Westheide Thomas E Schlaepfer Wolfgang Maier Kai-Uwe Kühn 《Neuropsychopharmacology》2005,30(2):381-390
Combined serotonin-2A (5-HT(2A)) and dopamine-2 (D2) receptor blockade has been proposed as a candidate mechanism by which second-generation antipsychotics (SGAs) improve both cognition and negative symptoms in schizophrenic patients, in contrast to antipsychotics of the first generation. The SGA amisulpride, however, only binds to D2/D3 receptors, which makes it an interesting tool to test this assumption. In a randomized controlled trial, 52 schizophrenic patients were allocated to treatment with either olanzapine (10-20 mg/day) or amisulpride (400-800 mg/day). A comprehensive neuropsychological test battery and clinical ratings were used to assess participants at inclusion and after 4 and 8 weeks. Cognitive improvements of moderate size were observed, with effect sizes similar to those obtained in previous studies on the cognitive effects of SGAs. Importantly, amisulpride was not inferior to olanzapine for any cognitive domain. Combined 5-HT(2A)/D2 receptor blockade is probably not necessary for cognitive improvement by SGAs. 相似文献
105.
106.
Folke Brinkmann Hans H Diebner Chantal Matenar Anne Schlegtendal Lynn Eitner Nina Timmesfeld Christoph Maier Thomas Lücke 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(37)
IntroductionSocio-economic and ethnic background have been discussed as possible risk factors for SARS-CoV-2 infections in children. Improved knowledge could lead to tailored prevention strategies and help improve infection control.AimWe aimed to identify risk factors for SARS-CoV-2 infections in children in the first and second wave of the pandemic.MethodsWe performed an observational population-based cohort study in children (6 months–18 years) scheduled for legally required preventive examination and their parents in a metropolitan region in Germany. Primary endpoint was the SARS-CoV-2 seroconversion rate during the study period. Risk factors assessed included age, pre-existing medical conditions, socio-economic factors and ethnicity.ResultsWe included 2,124 children and their parents. Seroconversion rates among children in all age groups increased 3–4-fold from June 2020 to February 2021. Only 24 of 58 (41%) seropositive children reported symptoms. In 51% of infected children, at least one parent was also SARS-CoV-2-positive. Low level of parental education (OR = 3.13; 95% CI: 0.72–13.69) non-significantly increased the risk of infection. Of the total cohort, 38.5% had a migration background, 9% of Turkish and 5% of Middle Eastern origin, and had the highest risk for SARS-CoV-2 infections (OR = 6.24; 95% CI: 1.38–28.12 and OR = 6.44 (95% CI: 1.14–36.45) after adjustment for other risk factors.ConclusionIn the second half of 2020, seroprevalence for SARS-CoV-2 in children increased especially in families with lower-socioeconomic status. Culture-sensitive approaches are essential to limit transmission and could serve as a blueprint for vaccination strategies. 相似文献
107.
Li F Maskey RP Qin S Sattler I Fiebig HH Maier A Zeeck A Laatsch H 《Journal of natural products》2005,68(3):349-353
In our screening of marine Streptomycetes for bioactive principles, two novel antitumor antibiotics designated as chinikomycins A (2a) and B (2b) were isolated together with manumycin A (1), and their structures were elucidated by a detailed interpretation of their spectra. Chinikomycins A (2a) and B (2b) are chlorine-containing aromatized manumycin derivatives of the type 64-pABA-2 with an unusual para orientation of the side chains. They exhibited antitumor activity against different human cancer cell lines, but were inactive in antiviral, antimicrobial, and phytotoxicity tests. 相似文献
108.
Herpes genitalis is commonly seen by the obstetrician-gynecologist. Prolonged persistence of herpes is unusual and may herald an underlying disorder. A case of chronic primary herpes is presented, in which the diagnosis of acquired immunodeficiency syndrome was delayed because of a low degree of suspicion. 相似文献
109.
E. Kattner F. Maier M. Gonser K.T.M. Schneider F. Kainer T. Somville K. Vetter U. Sch?fer-Graf K. Schunk M. Mandl I. M��ller-Hansen Prof. Dr. C. B��hrer 《Monatsschrift für Kinderheilkunde》2011,159(1):57-62
All diabetic women are advised to give birth in a hospital with a pediatric service that allows for continuous intravenous glucose administration, precluding the need for out-of-house transfer of the infant. Women with pre-pregnancy diabetes or on insulin treatment during pregnancy should give birth in a hospital offering round-the-clock neonatal care. Early (breast) feeding is of paramount importance and should be started 30?min after birth, subsequently every 2?C3?h. A mandatory preprandial blood glucose measurement should be taken 2?C3?h after birth and again immediately before the infant is transferred out of the delivery room; subsequent preprandial measurements at 6, 12, and possibly 24?h of age. In the event of three consecutive values of >2.5?mmol/l (45?mg/dl), further controls may be dispensed with. Simultaneously, infants should be checked for symptoms of hypoglycemia by a midwife or nurse on the maternity unit. Clinical findings suspicious for hypoglycemia should prompt immediate blood glucose determinations. Blood glucose concentrations below 2?mmol/l (36?mg/dl; in infants without symptoms) or 2.5?mmol/l (45?mg/dl; in infants with hypoglycemia-related symptoms, prior hypoglycemia, or following asphyxia) require immediate intervention in the form of feeding (preferably breast milk, otherwise hydrolyzed formula, or hydrolyzed starch solution only temporarily), by gavage if necessary. Intravenous glucose administration if blood glucose falls below 1.7?mmol/l (30?mg/dl). Routine echocardiography or laboratory tests (Ca2+, Mg2+, hematocrit, bilirubin) are not necessary unless otherwise indicated. Breast feeding should be consistently encouraged before and after delivery. 相似文献
110.
Wobst I Schiffmann S Birod K Maier TJ Schmidt R Angioni C Geisslinger G Grösch S 《Biochemical pharmacology》2008,76(1):62-69
Dimethylcelecoxib (DMC), a derivative of celecoxib, has been developed to distinguish between the COX-dependent and COX-independent anti-carcinogenic effects of celecoxib. Although DMC has been shown to have no COX-inhibitory activity, it is important to ensure that DMC has no other influence on prostaglandin production. Interestingly, in this study we show that DMC inhibits PGE(2) production in vitro in the low micromolar range in different cancer cell lines. This effect can be at least partly explained by our findings that DMC inhibits microsomal prostaglandin E synthase-1 (mPGES-1) activity in a cell-free assay. Moreover, it prevents mPGES-1 up-regulation after stimulation of HeLa cells with IL-1beta and TNFalpha. Conversely, DMC has no effect on the expression levels of COX-1, COX-2, cytosolic PGES (cPGES) or mPGES-2 in these cells. However, in the cell-free assay DMC inhibits mPGES-1 to a maximum of 65% only and concentrations needed for inhibition of mPGES-1 activity are about 10-fold higher than needed for inhibition of PGE(2) production in cell culture. This suggests that DMC also has an impact on other proteins involved in PGE(2) production. In cell culture experiments the anti-proliferative effect of DMC, measured by the WST-1 assay, seems not to be dependent on PGE(2) inhibition, as DMC was equally effective in unstimulated HeLa cells as well as in stimulated HeLa cells, and the addition of external PGE(2) did not reverse the anti-proliferative effect of DMC in HCA-7 cells. We conclude that DMC is not a suitable non-prostaglandin-inhibiting control substance for research purposes. 相似文献