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排序方式: 共有5896条查询结果,搜索用时 386 毫秒
91.
Kirsten M. Selnæs Ingrid S. Gribbestad Helena Bertilsson Alan Wright Anders Angelsen Arend Heerschap May‐Britt Tessem 《NMR in biomedicine》2013,26(5):600-606
MR metabolic profiling of the prostate is promising as an additional diagnostic approach to separate indolent from aggressive prostate cancer. The objective of this study was to assess the relationship between the Gleason score and the metabolic biomarker (choline + creatine + spermine)/citrate (CCS/C) measured by ex vivo high‐resolution magic angle spinning MRS (HR‐MAS MRS) and in vivo MRSI, and to evaluate the correlation between in vivo‐ and ex vivo‐measured metabolite ratios from spatially matched prostate regions. Patients (n = 13) underwent in vivo MRSI prior to radical prostatectomy. A prostate tissue slice was snap‐frozen shortly after surgery and the locations of tissue samples (n = 40) collected for ex vivo HR‐MAS were matched to in vivo MRSI voxels (n = 40). In vivo MRSI was performed on a 3T clinical MR system and ex vivo HR‐MAS on a 14.1T magnet. Relative metabolite concentrations were calculated by LCModel fitting of in vivo spectra and by peak integration of ex vivo spectra. Spearman's rank correlations (ρ) between CCS/C from in vivo and ex vivo MR spectra, and with their corresponding Gleason score, were calculated. There was a strong positive correlation between the Gleason score and CCS/C measured both in vivo and ex vivo (ρ = 0.77 and ρ = 0.69, respectively; p < 0.001), and between in vivo and ex vivo metabolite ratios from spatially matched regions (ρ = 0.67, p < 0.001). Our data indicate that MR metabolic profiling is a potentially useful tool for the assessment of cancer aggressiveness. Moreover, the good correlation between in vivo‐ and ex vivo‐measured CCS/C demonstrates that our method is able to bridge MRSI and HR‐MAS molecular analysis. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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《Gait & posture》2021
BackgroundVarious types of footwear fixation can dramatically alter gait characteristics, and could potentially contribute to an increased risk of falls in the elderly. However, no studies have been conducted to analyze the effects of footwear fixation on joint angle variabilities, particularly during the entire gait cycle.Research questionDoes the fixation of footwear significantly affect the lower limb joint angle variabilities during the gait cycle?MethodsPrincipal component analysis (PCA) was conducted on 20 healthy adults using 3D spatio-temporal data of the pelvis and lower limb joint angle that were collected during the entire gait cycle with the footwear in various conditions (well-fixated footwear, less-fixated footwear, slippers, and bare feet). Kinematic waveforms were reconstructed from the PCA data, which were used to determine the distinct differences in joint angle variabilities between footwear conditions.ResultsThe results showed large variability in the knee- and ankle-joint angles on the sagittal plane when walking in the loose condition (less-fixated footwear, slippers, and bare feet) compared with those in the well-fixated footwear condition.SignificanceThese results demonstrate the effect of footwear fixation on the joint angle variabilities of the elderly while walking. The increase in the knee- and ankle-joint angle variabilities when walking with less-fixated footwear could be a risk factor for falls. 相似文献
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IntroductionThe significant symptom overlap between progressive supranuclear palsy (PSP) and other parkinsonian neurodegenerative diseases frequently results in misdiagnosis. However, neuroimaging can be used to quantify disease-related morphological changes and specific markers. The cerebral peduncle angle (CPA) has been shown to differentiate clinically diagnosed PSP from other parkinsonian diseases but this result has yet to be confirmed in autopsy-proven disease.MethodsMagnetic resonance imaging (MRI) scans were obtained for 168 patients representing 69 medical facilities. Following randomization, the images were divided into two groups (Type 1 and Type 2) based upon midbrain morphological differences. Two readers were blinded and independently measured the CPA of 146 patients with autopsy-proven progressive supranuclear palsy (PSP; n = 54), corticobasal degeneration (n = 16), multiple system atrophy (MSA; n = 11) and Lewy body disease (n = 65).ResultsApplying two separate measurement techniques revealed no statistically significant differences in CPA measurements among any study groups regardless of classification measurement approach. The interobserver agreement showed significant differences in measurements using the Type 2 approach.ConclusionMeasuring the CPA on MRI is not a reliable way of differentiating among patients with PSP, corticobasal degeneration, MSA, or Lewy body disease. 相似文献
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《Journal of the Anatomical Society of India》2014,63(2):110-116
IntroductionDermatoglyphic patterns have been studied in schizophrenia and there is now evidence relating aspects of the dermatoglyphic profiles of the hands to schizophrenia.1,2 But there has been no study on whether treatment resistance can be predicted from the dermatoglyphic profile of an individual. This study was done to determine whether abnormal neurodevelopmental markers were more frequent in schizophrenics non-responsive to routine treatment and whether treatment resistance can be predicted by studying the dermatoglyphic profile of an individual.MethodsFinger and palm prints of 144 schizophrenic patients responsive to treatment and 44 schizophrenic patients non-responsive were taken. Finger print patterns, palmar patterns, palmar flexion creases, total ridge counts and atd angles were studied. The analysis was done using SPSS 11.0.ResultsThe results showed there was increased pattern frequency in the I3 area of the left hand of non-responders and in the I4 area of the right hand of responders. atd angle was decreased in the left hand of non-responders. There was increased frequency of the Simian type I crease in male non-responders and Sydney line in female non-responders.DiscussionCertain dermatoglyphic abnormalities occur more frequently in non-responders and with the help of these abnormalities, a schizophrenic patient likely to develop treatment resistance can be detected. 相似文献
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《The Knee》2020,27(6):1801-1810
BackgroundGenu varum is one of the most common anatomical variations of knee alignment which is considered a risk factor for anterior knee pain and anterior cruciate ligament injury among football players. Considering that millions of children participate in high-level football training, the purpose of this study was to determine the genu varum development in adolescent football players and non-athlete peers. The hypothesis of this study was that genu varum incidence was higher in adolescent football players compared with non-athletic peers.MethodsThe design was a cross-sectional study. Two-hundred and thirty-seven male football players (FG) and aged-matched and anthropometrically similar non-athletes (CG) were recruited into the study. The quadriceps angle and intercondylar–intermalleolar distance were measured to evaluate the leg alignment. The distance between the medial edges of the condyles and malleoli was measured in millimeters using a digital caliper while angle measurements were performed using a photographic technique in a standing position. To analyze the variables, comparison, correlation and regression statistical tests were performed.ResultsThe intercondylar–intermalleolar distance and quadriceps angle values were significantly higher in FG than CG in all ages. In FG, a very strong correlation was found between number of training years and the intercondylar–intermalleolar distance. The prevalence of genu varum was markedly higher in FG than CG (~37% vs. 2%, respectively) based on intercondylar–intermalleolar distance.ConclusionThis study determined that the prevalence of genu varum and abnormal quadriceps angles in adolescent football players is significantly higher compared with their non-athletic peers. 相似文献
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