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排序方式: 共有497条查询结果,搜索用时 15 毫秒
1.
E S C Korf E C W van Straaten F-E de Leeuw W M van der Flier F Barkhof L Pantoni A M Basile D Inzitari T Erkinjuntti L-O Wahlund E Rostrup R Schmidt F Fazekas P Scheltens 《Diabetic medicine》2007,24(2):166-171
HYPOTHESIS: Based on recent findings on the association between vascular risk factors and hippocampal atrophy, we hypothesized that hypertension and diabetes mellitus (DM) are associated with medial temporal lobe atrophy (MTA) in subjects without disability, independent of the severity of white matter hyperintensities. METHODS: In the Leukoaraiosis And DISability in the elderly (LADIS) study, we investigated the relationships between DM, hypertension, blood pressure and MTA in 582 subjects, stratified by white matter hyperintensity severity, using multinomial logistic regression. MTA was visually scored for the left and right medial temporal lobe (score 0-4), and meaned. RESULTS: Mean age was 73.5 years (sd 5.1), 54% was female. Of the subjects, 15% had DM, and 70% had a history of hypertension. The likelihood of having MTA score 3 was significantly higher in subjects with DM (OR 2.9; 95% CI: 1.1-7.8) compared with an MTA score of 0 (no atrophy). The odds ratio for MTA score 2 was not significantly increased (OR 1.8; CI: 0.9-4). Systolic and diastolic blood pressure and a history of hypertension were not associated with MTA. There was no interaction between DM and hypertension. Stratification on white matter hyperintensities (WMH) did not alter the associations. CONCLUSION: Our study strengthens the observation that MTA is associated with DM, independently of the amount of small vessel disease as reflected by WMH. 相似文献
2.
Neurofibromatosis 1 (NF1) is an autosomal dominant disorder caused by genetic alterations of the NF1 gene on 17q11.2. About 30% of NF1 patients develop plexiform neurofibromas (PNFs), which often cause severe clinical deficits. To determine whether there is a certain genotype underlying PNFs or subtypes of PNFs, we screened 42 NF1 patients from 41 families with PNFs for mutations in the NF1 gene. In 33 out of the 41 (80%) unrelated patients NF1 mutations were found, 24 are novel while the other 9 have been described in previous studies. The 33 mutations included 23 nonsense and frameshift, six splice and four missense mutations. The tumors in these patients had various sizes and features/growth characteristics. No correlation was found between the type or location of the NF1 mutations and size, location or feature of the PNFs, suggesting that many types of NF1 mutations can lead to development of PNFs. 相似文献
3.
Lim DJ Rubenstein AE Evans DG Jacks T Seizinger BG Baser ME Beebe D Brackmann DE Chiocca EA Fehon RG Giovannini M Glazer R Gusella JF Gutmann DH Korf B Lieberman F Martuza R McClatchey AI Parry DM Pulst SM Ramesh V Ramsey WJ Ratner N Rutkowski JL Ruttledge M Weinstein DE 《Journal of neurogenetics》2000,14(2):63-106
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The Bioperl toolkit: Perl modules for the life sciences 总被引:36,自引:4,他引:36
Stajich JE Block D Boulez K Brenner SE Chervitz SA Dagdigian C Fuellen G Gilbert JG Korf I Lapp H Lehväslaiho H Matsalla C Mungall CJ Osborne BI Pocock MR Schattner P Senger M Stein LD Stupka E Wilkinson MD Birney E 《Genome research》2002,12(10):1611-1618
The Bioperl project is an international open-source collaboration of biologists, bioinformaticians, and computer scientists that has evolved over the past 7 yr into the most comprehensive library of Perl modules available for managing and manipulating life-science information. Bioperl provides an easy-to-use, stable, and consistent programming interface for bioinformatics application programmers. The Bioperl modules have been successfully and repeatedly used to reduce otherwise complex tasks to only a few lines of code. The Bioperl object model has been proven to be flexible enough to support enterprise-level applications such as EnsEMBL, while maintaining an easy learning curve for novice Perl programmers. Bioperl is capable of executing analyses and processing results from programs such as BLAST, ClustalW, or the EMBOSS suite. Interoperation with modules written in Python and Java is supported through the evolving BioCORBA bridge. Bioperl provides access to data stores such as GenBank and SwissProt via a flexible series of sequence input/output modules, and to the emerging common sequence data storage format of the Open Bioinformatics Database Access project. This study describes the overall architecture of the toolkit, the problem domains that it addresses, and gives specific examples of how the toolkit can be used to solve common life-sciences problems. We conclude with a discussion of how the open-source nature of the project has contributed to the development effort. 相似文献
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Stevens H Jansen HM De Reuck J Lemmerling M Strijckmans K Goethals P Lemahieu I de Jong BM Willemsen AT Korf J 《Journal of the neurological sciences》1999,170(1):11-18
Axonal degeneration plays an important role in the accumulation of disability in patients with multiple sclerosis (MS). Pathological studies have demonstrated axonal damage, particularly in areas of acute inflammation and demyelination, and in chronic lesions. Axonal loss and its progression, which is associated with neurological disability, has also been demonstrated by magnetic resonance imaging (MRI) studies. The mechanisms of axonal loss are uncertain, but may involve axonal degeneration secondary to demyelination, or damage to the axonal cytoskeleton. Inflammatory mediators, including cytokines and proteolytic enzymes may contribute to axonal damage, as may nitric oxide. Axonal destruction may also be due to immune attack directed at axonal components. The realisation that axonal degeneration is a fundamental component of MS that may occur early in the disease course should alter the approach to management and open avenues to a more targeted immunotherapy aimed at reducing the progression of disability. 相似文献
8.
Jaep de Boer Folkert Postema Hillie Plijter-Groendijk Jakob Korf 《Pflügers Archiv : European journal of physiology》1991,419(1):1-6
A method is described for the measurement and on-line monitoring of muscular extracellular lactate concentration in both anaesthetized and freely moving rats. This method is based on microdialysis sampling and lactic dehydrogenase-catalysed nicotinamide adenine dinucleotide, reduced (NADH)-fluorescence detection techniques. In vivo calibration revealed a resting extracellular lactate concentration of 1.92±0.13 mmol/l (± SEM) in the gastrocnemius muscle of adult male Wistar rats (n=6), while the average whole-blood lactate level was 0.76±0.12 mmol/l (± SEM). This measured extracellular lactate concentration was 1.73-times higher than that deduced from the arterial lactate concentration. Blocking glycolysis with iodoacetate reduced the extracellular lactate concentration to 52±6% (± SEM, n= 4) of the resting level. The extracellular lactate concentration in rat gastrocnemius muscle had increased to significantly (P0.05) different levels, 2.4±0.03 (± SEM) or 4.0±0.55 (± SEM) times the control value, 1 h after aortic clamping (n=3) or cardiac arrest (n=3), respectively. Stimulation of the sciatic nerve induced elevations of the extracellular lactate concentration in the tibialis anterior muscle which were linearly related to the recorded isometric force-time integral. We also monitored on-line the changes in extracellular lactate concentration in the tibialis anterior muscle of a swimming rat. Our results indicate that microdialysis lactate reflects also intracellular metabolism. Lactography may be a useful alternative to biopsies and nuclear magnetic resonance spectroscopy in clinical medicine and physiology for the monitoring of metabolism in vivo. 相似文献
9.
Serum and brain levels of the tricyclic antidepressant drug imipramine (IMI) were studied in the rat under a variety of conditions. IV doses (range 1 nmol kg-1 to 15 mol kg-1, 350 ng–5mg kg-1) and administered 5 min before death, were linearly correlated with IMI levels in serum, frontal cortex, and cerebellum. In this experiment, the highest levels of IMI were achieved in the frontal and occipital cortex and the lowest levels were found in the brain stem. The regional distribution was more even in rats pretreated with thiopental or -hydroxybutyric acid, drugs that alter cerebral blood flow. After 20 min or more, tracer amounts of IMI injected IV to IMI-pretreated rats [1 or 17 days, daily dose 2×36 mol kg-1 (10 mg kg-1), last dose 89 mol kg-1 (25 mg kg-1), 2–3 h before death] exhibited a distribution pattern in serum and various brain regions similar to that of the unlabeled drug. In the latter experiments, content (per volume) of the tracer or unlabeled IMI was more than 25-fold higher in various brain areas than in serum. It is concluded that despite large differences in drug levels in serum or brain, a close relationship is maintained under the conditions studied.deceased 相似文献
10.
Brian Weiss Brigitte C. Widemann Pamela Wolters Eva Dombi Alexander Vinks Alan Cantor John Perentesis Elizabeth Schorry Nicole Ullrich David H. Gutmann James Tonsgard David Viskochil Bruce Korf Roger J. Packer Michael J. Fisher 《Neuro-oncology》2015,17(4):596-603
BackgroundPlexiform neurofibromas (PNs) are benign peripheral nerve sheath tumors that arise in one-third of individuals with neurofibromatosis type 1 (NF1). They may cause significant disfigurement, compression of vital structures, neurologic dysfunction, and/or pain. Currently, the only effective management strategy is surgical resection. Converging evidence has demonstrated that the NF1 tumor suppressor protein, neurofibromin, negatively regulates activity in the mammalian Target of Rapamycin pathway.MethodsWe employed a 2-strata clinical trial design. Stratum 1 included subjects with inoperable, NF1-associated progressive PN and sought to determine whether sirolimus safely and tolerably increases time to progression (TTP). Volumetric MRI analysis conducted at regular intervals was used to determine TTP relative to baseline imaging.ResultsThe estimated median TTP of subjects receiving sirolimus was 15.4 months (95% CI:14.3–23.7 mo), which was significantly longer than 11.9 months (P < .001), the median TTP of the placebo arm of a previous PN clinical trial with similar eligibility criteria.ConclusionsThis study demonstrated that sirolimus prolongs TTP by almost 4 months in patients with NF1-associated progressive PN. Although the improvement in TTP is modest, given the lack of significant or frequent toxicity and the availability of few other treatment options, the use of sirolimus to slow the growth of progressive PN could be considered in select patients. 相似文献