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排序方式: 共有841条查询结果,搜索用时 0 毫秒
41.
42.
Koivisto M Virjonen T Heikkilä T Lehto VP 《Journal of pharmaceutical and biomedical analysis》2004,36(3):559-564
The crystallographic texture, i.e. the preferred orientation of crystallites of delta-mannitol samples, has been experimentally determined by pole figure analysis. The pole figures were measured with an X-ray diffraction texture goniometer. It was found that already the uncompressed delta-mannitol powder sample was slightly texturized so that the (0 2 0) plane was parallel to the upper surface of the sample. The degree of preferred orientation was found to significantly increase when the powder was compressed to a tablet with the minimum (74MPa) compression pressure. Nevertheless, the direction of the texture remained parallel to the tablet surface. Maximum compression (740MPa) did not increase the degree of preferred orientation further. The compression time (0 or 60s) was not found to noticeably affect the strength or direction of the texture. The extent of the texture inside the tablet was determined with a tablet surface grinding experiment. The degree of preferred orientation was found to decrease under the surface while the orientation remained the same. The results were confirmed with orientation distribution function (ODF) calculations. 相似文献
43.
Postnatal changes in concentrations of free and bound leptin 总被引:4,自引:0,他引:4
Hytinantti TK Juntunen M Koistinen HA Koivisto VA Karonen SL Andersson S 《Archives of disease in childhood. Fetal and neonatal edition》2001,85(2):F123-F126
AIM: To evaluate the effect of maternal diabetes on the concentrations of free and bound leptin at birth and during postnatal adaptation. METHODS: Total, bound, and free leptin concentrations and the percentage of free leptin were measured in cord plasma and plasma at 3 days of age of 13 term infants of mothers with gestational diabetes mellitus (GDM) and 13 term infants of healthy mothers. Gestational age was 40.2 (1.4) weeks, and birth weight was 3693 (549) g (means (SD)). RESULTS: At birth, infants of mothers with GDM had significantly higher concentrations of total, bound, and free leptin and a higher percentage of free leptin (all p < 0.05). In all infants, these concentrations were significantly lower at 3 days of age than at birth (all p < 0.003), and the differences in concentrations of total, bound, and free leptin between the two groups were no longer significant. In infants of mothers with GDM, the percentage of free leptin remained unchanged, and was higher (p<0.05) than in infants of healthy mothers; in the latter group the percentage of free leptin significantly declined (p = 0.02). CONCLUSIONS: GDM appears to influence fetoplacental leptin metabolism. This effect may be mediated through altered maternal glucose metabolism, or insulinaemia, or both. 相似文献
44.
Vuorio AF Aalto-Setälä K Koivisto UM Turtola H Nissen H Kovanen PT Miettinen TA Gylling H Oksanen H Kontula K;Finnish FH-group 《Annals of medicine》2001,33(6):410-421
Familial hypercholesterolaemia (FH) is an autosomal co-dominantly inherited condition resulting from mutations of the low-density lipoprotein (LDL) receptor which occur in heterozygous form in approximately one in 500 individuals. Clinically, FH is characterized by 2-3-fold elevation of serum LDL cholesterol levels, accelerated development of atherosclerotic vascular disease, and, if untreated, shortened lifespan. The Finnish population, which represents a genetic isolate, offers exceptional possibilities for genetic-epidemiological studies on FH, as a handful of founder gene mutations account for the majority of FH cases in Finland. This review summarizes data from our FH studies carried out since 1985. We wish to emphasize the continuum of genotype-phenotype relationships, the importance of molecular diagnosis, the detection of novel risk factors of vascular disease, and innovations inhibiting cholesterol absorption for the modern treatment of FH. 相似文献
45.
Laakso MP Hiltunen Y Könönen M Kivipelto M Koivisto A Hallikainen M Soininen H 《Journal of neural transmission (Vienna, Austria : 1996)》2003,110(3):267-275
Summary. Apolipoprotein E (ApoE) genotype has been shown to influence results in neuroimaging studies using a number of various imaging
modalities. No in vivo data exists on whether or not there are ApoE-related changes observable by proton magnetic resonance
spectroscopy (MRS). In this study we measured absolute peak areas of proton MR spectra obtained from the occipital cortex
in 22 non-demented elderly with (n = 8) or without (n = 14) the ApoE ε4 allele. No statistically significant differences were
found in levels of N-acetyl aspartate, myo-inositol, or choline containing compounds between the groups. Instead, compared
with the non-carriers, the levels of creatine were significantly lower in the ε4 carriers, suggesting increased metabolic
demands in the brain of the ε4 carriers. The levels of creatine also correlated significantly with age and performance on
the Mini-Mental State Examination test in the ε4 carriers, but not in the non-carriers. These findings may be of significant
clinical interest as potential indicator of incipient AD, and also from therapeutical point of view given the potential neuroprotective
effects of creatine.
Received February 18, 2002; accepted August 5, 2002 Published online December 9, 2002
Acknowledgements This study was supported by the Research Council for Health of the Academy of Finland, the Finnish Neurology Foundation,
the Instrumentarium Research Foundation, and the Farmos Research Foundation.
Authors' address: M. Laakso, Department of Neurology, Bldg. 5, Kuopio University Hospital, P.O.Box 1777, 70211 Kuopio, Finland,
e-mail: mikko.laakso@uku.fi
Abbreviations AD Alzheimer's disease, ApoE apolipoprotein E, MI myo-inositol, MMSE Mini-Mental State Examination, MRI magnetic resonance imaging, MRS magnetic resonance spectroscopy, NAA N-acetyl aspartate. 相似文献
46.
Rökman A Koivisto PA Matikainen MP Kuukasjärvi T Poutiainen M Helin HJ Karhu R Kallioniemi OP Schleutker J 《The Prostate》2001,46(3):233-239
BACKGROUND: Germline mutations in recessive cancer predisposition genes are uncovered by somatic genetic deletions during tumor development. Analysis of genetic changes in tumor tissues from patients with an inherited predisposition may therefore highlight regions of the genome containing susceptibility or modifier genes. Our aim was to characterize genetic changes in familial prostate cancer METHODS: Twenty-one primary prostate cancers from 19 Finnish prostate cancer families were analyzed for somatic genetic changes by comparative genomic hybridization (CGH). RESULTS: The average number of genetic alterations per tumor was 4.0 +/- 1.9, distributed equally among losses and gains. The most common losses were found at chromosomal regions 13q14-q22 (29%), 8p12-pter (24%), and 6q13-q16 (14%), and the most common gains at 19p (25%), 19q (14%) and 7q (14%). CONCLUSIONS: These results suggest that prostate cancers in genetically predisposed individuals arise for the most part through similar somatic genetic progression pathways as sporadic prostate cancers. This also implies that the biological properties of tumors from the two groups may not be different from one another. 相似文献
47.
Laakso MP Vaurio O Koivisto E Savolainen L Eronen M Aronen HJ Hakola P Repo E Soininen H Tiihonen J 《Behavioural brain research》2001,118(2):187-193
Neurobiology of psychopathy is of interest, not only because neural underpinnings of psychopathy remain obscure, but also because psychopaths may provide a model to study violent behavior, neurology of morals and impaired decision-making. Medial temporal lobe pathology has been suggested to be a part of the neural systems dysfunction which manifests as violent and psychopathic behavior. Yet, so far no sound evidence of neuroanatomical correlates for psychopathic behavior has been found. In this study regional hippocampal volumes were measured using magnetic resonance imaging in 18 habitually violent offenders with antisocial personality disorder and type 2 alcoholism (derived from forensic psychiatric evaluation). The regional volumes along the anteroposterior axis of the hippocampus were correlated with the subjects' degree of psychopathy as evaluated by the Psychopathy Checklist-Revised. Strong negative correlations, up to -0.79, were observed, among the study subjects, between the psychopathy scores and the posterior half of the hippocampi bilaterally. These data are in accordance with experimental studies proposing that lesions of the dorsal hippocampus impair acquisition of conditioned fear, and with theories on psychopathology according to which one of the central features in the birth of psychopathy is a deficit in acquisition of conditioned fear. 相似文献
48.
Laakso MP Tiihonen J Syvälahti E Vilkman H Laakso A Alakare B Räkköläinen V Salokangas RK Koivisto E Hietala J 《Schizophrenia Research》2001,50(1-2):3-7
Magnetic resonance imaging (MRI) studies have frequently, although not unambiguously, reported hippocampal volume deficit in schizophrenia. Data on the hippocampal volumes in first-episode schizophrenia, however, are sparse. In addition, a recent topographic MRI study proposed a regionally specific volume loss in the hippocampus of chronic schizophrenics, but to date no reports have replicated this finding. In this study two-dimensional MRI-based topographic brain mapping was used to study the possibility of regional changes in the hippocampus of 22 controls and 18 patients with first-episode, neuroleptic-na?ve schizophrenia. Compared to controls, there were no significant differences between hippocampal volumes, regional volumes, or length of the hippocampus in the patients with schizophrenia. These data are at odds with the previous reports on hippocampal volume loss in first-episode schizophrenia, and with the hypothesis of regionally specific hippocampal volume deficit in schizophrenia. 相似文献
49.
50.
Jehkonen M Ahonen JP Dastidar P Koivisto AM Laippala P Vilkki J Molnár G 《Acta neurologica Scandinavica》2000,101(3):195-201
OBJECTIVE: The aim was to study the role of visual neglect in acute right hemisphere brain infarct as a predictor of poor functional outcome during the first year after stroke. In particular, we were interested in the additional value of neglect measures besides hemiparesis, hemianopia, cognitive deficits and age. PATIENTS AND METHODS: A consecutive series of 57 patients with a neuroradiologically verified right hemisphere infarct was examined within 10 days of the stroke. Fifty patients were followed up for 1 year. Neglect was measured with the Conventional and the Behavioural subtests of the Behavioural Inattention Test (BITC and BITB, respectively). The predictors were determined at the 10-day examination. Functional outcome was assessed 3, 6 and 12 months after the onset with the Frenchay Activities Index. RESULTS: Neglect in BITB was the best single predictor, which together with high age formed the best combination of predictors for poor functional outcome at each follow-up. Hemiparesis was also included in this prediction model at the 3-month follow-up, but hemianopia, BITC, or visuoconstructional and memory deficits showed no additional predictive value. However, neglect usually recovered soon. When neurological and cognitive deficits were assessed at the same time as the outcome, hemiparesis rather than neglect was the strongest correlate of poor outcome. CONCLUSION: Neglect in acute stroke is an important predictor of poor functional recovery. Residual neglect, which could be compensated in the follow-up tests, may nevertheless restrict patients' real-life activities and hobbies. 相似文献