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1.
Diffusion-weighted imaging study of patients with essential tremor.   总被引:1,自引:0,他引:1  
The pathophysiology of essential tremor (ET) is unknown. PET and fMRI studies have revealed bilateral activation and (1)H-MRS studies metabolic abnormalities in the cerebellum and other functionally related brain structures in ET. Diffusion-weighted imaging (DWI) was used to search for evidence of tissue integrity abnormalities in these areas in ET patients and 10 matched controls by calculating water apparent diffusion coefficients (ADCs). Regions of interest included the left and right cerebellum, red nucleus, thalamus, caudate, putamen, pallidum, and frontal white matter. Histograms of ADCs were generated for all pixels in the infratentorial compartment and manually segmented areas corresponding to brainstem, vermis, and cerebellar hemispheres. ADC values were similar in all brain areas in patients and controls. Our study did not detect changes affecting the investigated brain regions in ET patients. These findings argue against major structural damage in the ET brain, although more subtle neurodegenerative changes cannot be ruled out.  相似文献   
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Constituents of Fagaceae (Cupuliferae), XIX: Triterpene Saponins and Acylated Flavonoids from Quercus robur L. var. stenocarpa Beck. In addition to four known glycosides from leaves of Quercus robur L. var. stenocarpa Beck. a new triterpene saponin has been isolted and identified as 28-β-d-glucopyranosyl ester of the 2α,3β,19α-trihydroxy-olean-12-ene-24,28-dioic acid ( I ).  相似文献   
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Umbelliferose has been isolated from the fruits of CACHRYS FERULACEA (L.) Calestani and the sugar sequence has been determined by NMR spectroscopic 2D-COLOC technique. The method of identification of the trisaccharide, which occurs only in the Umbelliferae family and may have a chemotaxonomic significance, is described and briefly discussed.  相似文献   
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The purpose of the study was to determine the effect of anti-inflammatory doses of ibuprofen on neutrophils, neutrophil O2* production, and markers of muscle injury. Males (n=10) performed 2 bouts of one-arm eccentric exercise on opposite arms separated by three weeks. Subjects received 2400 mg x d(-1) of ibuprofen or a placebo 5 d before exercise and during 10 d of recovery. Measurements were made before the treatments, pre-exercise, at 4 h, and at 1, 2, 3, 4 and 10 d post-exercise. Circulating neutrophil counts were similar between the treatments at the sampling points. Neutrophil counts were higher (p<0.05) for ibuprofen and were elevated (p<0.05) at 4h post-exercise relative to pre-exercise in both treatments. Stimulated neutrophil O2* production was lower for ibuprofen relative to placebo at pre-exercise and was increased (p<0.05) at 4 h and 4 d of both treatments. CK activity at 3 d post-exercise was lower (p<0.05) for ibuprofen relative to placebo. Isometric strength, soreness, tenderness, and arm angles were similar between the treatments. In conclusion, anti-inflammatory doses of ibuprofen reduced CK activity but not the neutrophil response or other indirect markers of muscle injury during recovery from eccentric arm exercise.  相似文献   
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ObjectiveThe aim of the study was to analyze the Quality of life (QoL) scores in a single institution series of locally advanced cervical cancer patients (LACC) administered preoperative chemoradiation, compared to early stage disease (ECC) patients undergoing radical surgery.MethodsThe following criteria were required in order to enroll patients: age between 18 and 65years at initial diagnosis, at least 12months from the end of treatment, no evidence of recurrence/second malignancy. The SF-36 questionnaire on general health, and the HADS questionnaire on mental distress were utilized.Results93 subjects were available for the analysis. At time of analysis, median follow-up was 30months (range 12–120). LACC patients showed QoL scores comparable to ECC patients with the exception of physical functioning (mean ± SD = 69.0 ± 13.1 versus mean ± SD = 85.4 ± 16.2, p value = 0.0007). In the group of LACC patients, the presence of co-morbidities was significantly associated with the impairment of almost all subscales of QoL. A low education level and the status of unemployment were documented to negatively impact on the vast majority of SF-36 subscale scores. In the multivariate analysis, the presence of co-morbidities, low educational level, age> 50years, and unemployment maintained their independent negative association with poor QoL scores. The percentage of cases with high levels HADS-anxiety was higher in LACC than ECC patients (27.6% versus 8.6%, p value = 0.034).ConclusionsLACC patients administered preoperative chemoradiation showed QoL scores comparable to EEC patients, and a higher proportion of anxiety disorders; low educational level and unemployment status were mainly associated with poor QoL scores.  相似文献   
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SUMMARY. This study aims to evaluate by the use of 24‐hour combined multichannel intraluminal impedance and pH monitoring (MII‐pH) the efficacy of the Nissen fundoplication in controlling both acid and nonacid gastroesophageal reflux (GER) in patients that underwent Heller myotomy for achalasia. It has been demonstrated that fundoplication prevents the pathologic acid GER after Heller myotomy, but no objective data exists on the efficacy of this antireflux surgery in controlling all types of reflux events. The study population consisted of 20 patients that underwent laparoscopic Heller myotomy and Nissen fundoplication for achalasia. All patients were investigated with manometry and MII‐pH. MII‐pH showed no evidence of postoperative pathologic GER. The overall number of GER episodes was normal in both the upright and recumbent position. This reduction was obtained because of the postoperative control of both the acid and nonacid reflux episodes. The Nissen fundoplication adequately controls both acid and nonacid GER after extended Heller myotomy. Further controls with MII‐pH are warranted to check at a longer follow‐up for the efficacy of this antireflux procedure in achalasic patients.  相似文献   
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OBJECTIVE: To evaluate the apoptotic effect of the chemokine growth-related oncogene alpha (GROalpha), which we recently reported to be up-regulated in osteoarthritis (OA) chondrocytes. Chondrocyte apoptosis is considered to be a major determinant of cartilage damage in OA, a disease resulting from the aberrant production of inflammatory mediators (cytokines and chemokines) and effectors (matrix metalloproteinases and reactive oxygen and nitrogen species) by chondrocytes. METHODS: We investigated the apoptotic effect of GROalpha on isolated human cells and on in vitro-cultured cartilage explants by conventional methods (morphology, detection of DNA fragmentation in situ and in solution, exposure of phosphatidylserine) and by analysis of "early" biochemical events (plasma membrane depolarization, activation of caspase 3, and phosphorylation of c-Jun N-terminal kinase/stress-activated protein kinase). RESULTS: We clearly demonstrated that GROalpha was able to initiate a series of morphologic, biochemical, and molecular changes that led to chondrocyte apoptosis. Moreover, we found that additional signals delivered from the extracellular matrix (ECM) were essential in the control of chondrocyte susceptibility to GROalpha-induced apoptosis, since cell death was detected only when cells were stimulated after reestablishment of their proper interactions with the ECM, or in cartilage explant samples with reduced ECM, as indicated by decreased Safranin O staining. CONCLUSION: GROalpha can induce apoptosis in articular chondrocytes, and the induction is dependent upon additional signals from the ECM. These findings are relevant to understanding the pathogenesis of OA, in view of the availability of the GROalpha chemokine in the joint space in the course of this rheumatic disease.  相似文献   
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