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91.
92.
Fin L Daouk J Morvan J Bailly P El Esper I Saidi L Meyer ME 《European journal of nuclear medicine and molecular imaging》2008,35(11):1971-1980
Purpose Respiratory motion causes uptake in positron emission tomography (PET) images of chest structures to spread out and misregister
with the CT images. This misregistration can alter the attenuation correction and thus the quantisation of PET images. In
this paper, we present the first clinical results for a respiratory-gated PET (RG-PET) processing method based on a single
breath-hold CT (BH-CT) acquisition, which seeks to improve diagnostic accuracy via better PET-to-CT co-registration. We refer
to this method as “CT-based” RG-PET processing.
Methods Thirteen lesions were studied. Patients underwent a standard clinical PET protocol and then the CT-based protocol, which consists
of a 10-min List Mode RG-PET acquisition, followed by a shallow end-expiration BH-CT. The respective performances of the CT-based
and clinical PET methods were evaluated by comparing the distances between the lesions’ centroids on PET and CT images. SUVMAX and volume variations were also investigated.
Results The CT-based method showed significantly lower (p = 0.027) centroid distances (mean change relative to the clinical method = −49%; range = −100% to 0%). This led to higher
SUVMAX (mean change = +33%; range = −4% to 69%). Lesion volumes were significantly lower (p = 0.022) in CT-based PET volumes (mean change = −39%: range = −74% to −1%) compared with clinical ones.
Conclusions A CT-based RG-PET processing method can be implemented in clinical practice with a small increase in radiation exposure. It
improves PET-CT co-registration of lung lesions and should lead to more accurate attenuation correction and thus SUV measurement. 相似文献
93.
In advanced uremia, parathyroid hormone (PTH) levels should be controlled at a moderately elevated level in order to promote normal bone turnover. As such, a certain degree of parathyroid hyperplasia has to be accepted. Uremia is associated with parathyroid growth. In experimental studies, proliferation of the parathyroid cells is induced by uremia and further promoted by hypocalcemia, phosphorus retention, and vitamin D deficiency. On the other hand, parathyroid cell proliferation might be arrested by treatment with a low-phosphate diet, vitamin D analogs, or calcimimetics. When established, parathyroid hyperplasia is poorly reversible. There exists no convincing evidence of programmed parathyroid cell death or apoptosis in hyperplastic parathyroid tissue or of involution of parathyroid hyperplasia. However, even considerable parathyroid hyperplasia can be controlled when the functional demand for increased PTH levels is removed by normalization of kidney function. Today, secondary hyperparathyroidism can be controlled in patients with long-term uremia in whom considerable parathyroid hyperplasia is to be expected. PTH levels can be suppressed in most uremic patients and this suppression can be maintained by continuous treatment with phosphate binders, vitamin D analogs, or calcimimetics. Thus modern therapy permits controlled development of parathyroid growth. When nonsuppressible secondary hyperparathyroidism is present, nodular hyperplasia with suppressed expression of the calcium-sensing receptor (CaR) and vitamin D receptor (VDR) has been found in most cases. An altered expression of some autocrine/paracrine factors has been demonstrated in the nodules. The altered quality of the parathyroid mass, and not only the increased parathyroid mass per se, might be responsible for uncontrollable hyperparathyroidism in uremia and after kidney transplantation. 相似文献
94.
Quantitative changes in testicular structure and function in rat exposed to mobile phone radiation 下载免费PDF全文
The possible effects of the electromagnetic fields (EMF) generated by mobile phones on reproductive functions have been discussed in recent years. The aim of this study was to evaluate the effects of EMF emitted from mobile phones on the rat testis morphology and histopathology using stereological techniques. We also investigated cortisol, testosterone, FSH and LH levels. A total of thirty‐two (n = 32) male Wistar albino rats were used in this study. Animals were randomly divided into four groups as control (C, n = 8), sham (Sh, n = 8), mobile phone speech (Sp, n = 8) and mobile phone standby (ST by). Morphometric measurements were made with the help of a computer‐assisted stereological analysis system. The testis weight and volume were significantly lower in the EMF exposed groups. The mean volume fraction of interstitial tissue was higher, but the volume fraction of tubular tissue was lower in the EMF‐exposed groups. The mean tubular and germinal tissue volume, seminiferous tubule diameter and germinal epithelium height were also lower in EMF exposed groups. The cortisol levels in the EMF‐exposed groups were significantly higher. In conclusion, the EMF created by mobile phones caused morphologic and histological changes by the affecting germinal epithelium tissue negatively. 相似文献
95.
Background
Even though there are several region-specific functional outcome questionnaires measuring neck disorders that have been developed in English-speaking countries, no Polish version has ever been validated. The purpose of our study was to translate, culturally adapt and validate the Neck Disability Index (NDI) and Copenhagen Neck Functional Disability Scale (CDS) for Polish-speaking patients with neck pain. 相似文献96.
Jean-Francois Catanzariti Marc-Alexandre Guyot Caroline Massot Hichem Khenioui Olivier Agnani Cécile Donzé 《European spine journal》2016,25(2):438-443
Purpose
Adolescent idiopathic scoliosis (AIS) is a three-dimensional deformity of the spine, with unknown origin. Some studies have noted impaired postural balance in AIS, in particular, difficulty to manage situations with sensory conflict. The motion sickness susceptibility can be secondary to a sensory conflict, for example, between visual and vestibular information. Our hypothesis is: patients with AIS have difficulty in managing situations with sensory conflict and therefore have increased motion sickness susceptibility. The purpose of this study was to evaluate in AIS subjects by evaluating their susceptibility to motion sickness, as compared to a control group.Methods
We conducted an analysis of data on motion sickness susceptibility collected prospectively from 2012, with the B score of motion sickness susceptibility questionnaire. This evaluation was completed for 65 adolescents (age 14.5 ± 1.6 year) with major right thoracic AIS (Cobb = 40.7° ± 13.1°) and 71 matched controls (14.6 ± 1.6 year).Results
Adolescents with major right thoracic AIS were more susceptible to motion sickness (B score = 5.3 ± 5.8) than controls (B score = 3.4 ± 3.7) with significant difference (p = 0.025).Conclusions
We interpret our results suggesting there is difficulty for patients with AIS to manage situations with sensory conflict. Previous studies focusing on situations with sensory conflict in AIS have required sophisticated technology. They are not accessible for routine patient management. Our research shows the same result with simple, non invasive, low-cost and quick method: B score of motion sickness susceptibility questionnaire.97.
Alicja Szymczyszyn Adrian Doroszko Ewa Szahidewicz-Krupska Piotr Rola Radosław Gutherc Jakub Jasiczek Grzegorz Mazur Arkadiusz Derkacz 《Lasers in medical science》2016,31(7):1301-1307
The effect of low-level laser therapy (LLLT) on the cardiovascular system is not fully established. Since the endothelium is an important endocrine element, establishing the mechanisms of LLLT action is an important issue.The aim of the study was to evaluate the effect of transdermal LLLT on endothelial function.In this study, healthy volunteers (n?=?40, age?=?20–40 years) were enrolled. N?=?30 (14 female, 16 male, mean age 30?±?5 years) constituted the laser-irradiated group (LG). The remaining 10 subjects (6 women, 4 men, mean age 28?±?5 years) constituted the control group (CG). Participants were subjected to LLLT once a day for three consecutive days. Blood for biochemical assessments was drawn before the first irradiation and 24 h after the last session. In the LG, transdermal illumination of radial artery was conducted (a semiconductor laser λ?=?808 nm, irradiation 50 mW, energy density 1.6 W/cm2 and a dose 20 J/day, a total dose of 60 J). Biochemical parameters (reflecting angiogenesis: vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), angiostatin; antioxidative status: glutathione (GSH) and the nitric oxide metabolic pathway: symmetric dimethylarginine (SDMA), asymmetric dimethylarginine (ADMA) and l-arginine) were assessed. In the LG, a significant increase in GSH levels and considerable decrease in angiostatin concentration following the LLLT were observed. No significant differences in levels of the VEGF, FGF, SDMA, ADMA were observed.LLLT modifies vascular endothelial function by increasing its antioxidant and angiogenic potential. We found no significant differences in levels of the nitric oxide pathway metabolites within 24 h following the LLLT irradiation. 相似文献
98.
Marek Szolkiewicz Elzbieta Sucajtys Wojciech Wolyniec Przemyslaw Rutkowski Ewa Stelmanska Justyna Korczynska Julian Swierczynski Boleslaw Rutkowski 《Journal of renal nutrition》2005,15(1):166-172
OBJECTIVE: Hyperlipidemia is a permanent finding in advanced renal failure. It is supposed to be responsible for the accelerated arteriosclerosis and cardiovascular complications observed in patients with that disease. The background is partially determined, however, our knowledge in this matter is not yet satisfactory. METHODS: This study is based on the experimental rat model of chronic renal failure (CRF). Considering white adipose tissue (WAT) lipogenesis upregulation in CRF, along with the determination of acetyl coenzyme A carboxylase (ACC) and fatty acid synthase (FAS) genes expression, we have measured WAT gene expression for sterol regulatory binding protein 1 (SREBP-1) at the level of protein mass and mRNA abundance. Furthermore, we have determined glucose uptake, glucose-to-CO 2 conversion rate, and glucose translocator (GLUT-4) gene expression in WAT. RESULTS: Upregulation of both FAS and ACC gene expression was found in WAT of CRF rats. It was accompanied by WAT SREBP-1 gene overexpression. Moreover, we have observed the increased glucose uptake, glucose to CO 2 conversion rate, and GLUT-4 gene expression in WAT of CRF rats in comparison with controls. CONCLUSION: SREBP-1 gene overexpression may contribute to enhanced lipogenesis upregulation in WAT of CRF rats. It is not excluded that the increased WAT glucose metabolism activity is also induced by this mechanism, although there is no evidence currently to that end. We hypothesize that the increased WAT lipogenesis capacity could be a part of mechanism(s) leading to CRF-induced hyperlipidemia. 相似文献
99.
Rafa? Leszczyński Stanislawa Gierek-Ciaciura Maria Formin?ka-Kapu?cik Ewa Mrukwa-Kominek Iwona Rokita-Wala 《Medical science monitor》2008,14(2):CR86-CR89
BACKGROUND: The purpose of our study was to assess intraocular pressure control (IOP) and postoperative complications in nonpenetrating very deep sclerectomy (NPVDS) with reticulated hyaluronic acid implant (SKGEL) and Mitomycin C (MMC). MATERIAL/METHODS: Fifty eyes from fifty patients with medically uncontrolled glaucoma were randomized to either the NPVDS or NPDS group. The NPVDS procedure was similar to traditional NPDS (control group); however, excision of sclera and exposure of ciliary body were also performed, and only a narrow scleral flap was retained at a distance of 0.5 mm from Schlemm's canal. Mitomycin-C 0.2 mg/ml was applied on and under the superficial flap of the sclera during both NPVDS and NPDS. Follow-up examinations were carried out at 1 week, and then at 1, 3, 6, and 12 months after surgery. Success was defined as IOP <22 mmHg with or without glaucoma medication and laser procedures. RESULTS: The 12-month success rate in the NPVDS group was 96%, not significantly higher than in the control group (88%, p=0.88). There was no statistically significant difference in IOP between the NPVDS (15.9+/-2.5 mmHg) and NPDS (16.3+/-3.6 mmHg) groups (p=0.57). Complications included four cases of hyphema, three of choroidal detachment (myopic eyes), and one of filtering bleb fibrosis in the NPVDS group, and three cases of hyphema, two of choroidal detachment (myopic eyes), and three of filtering bleb fibrosis in the NPDS group. CONCLUSIONS: NPVDS is an effective surgical modality for patients with glaucoma. The safety of NPVDS is comparable to that of NPDS. 相似文献
100.
Morrow DA Scirica BM Karwatowska-Prokopczuk E Murphy SA Budaj A Varshavsky S Wolff AA Skene A McCabe CH Braunwald E;MERLIN-TIMI Trial Investigators 《JAMA》2007,297(16):1775-1783
Context Ranolazine is a novel antianginal agent that reduces ischemia in patients with chronic angina but has not been studied in patients with acute coronary syndromes (ACS). Objective To determine the efficacy and safety of ranolazine during long-term treatment of patients with nonST-elevation ACS. Design, Setting, and Patients A randomized, double-blind, placebo-controlled, multinational clinical trial of 6560 patients within 48 hours of ischemic symptoms who were treated with ranolazine (initiated intravenously and followed by oral ranolazine extended-release 1000 mg twice daily, n = 3279) or matching placebo (n = 3281), and followed up for a median of 348 days in the Metabolic Efficiency With Ranolazine for Less Ischemia in NonST-Elevation Acute Coronary Syndromes (MERLIN)-TIMI 36 trial between October 8, 2004, and February 14, 2007. Main Outcome Measures The primary efficacy end point was a composite of cardiovascular death, myocardial infarction (MI), or recurrent ischemia through the end of study. The major safety end points were death from any cause and symptomatic documented arrhythmia. Results The primary end point occurred in 696 patients (21.8%) in the ranolazine group and 753 patients (23.5%) in the placebo group (hazard ratio [HR], 0.92; 95% confidence interval [CI], 0.83-1.02; P = .11). The major secondary end point (cardiovascular death, MI, or severe recurrent ischemia) occurred in 602 patients (18.7%) in the ranolazine group and 625 (19.2%) in the placebo group (HR, 0.96; 95% CI, 0.86-1.08; P = .50). Cardiovascular death or MI occurred in 338 patients (10.4%) allocated to ranolazine and 343 patients (10.5%) allocated to placebo (HR, 0.99; 95% CI, 0.85-1.15; P = .87). Recurrent ischemia was reduced in the ranolazine group (430 [13.9%]) compared with the placebo group (494 [16.1%]; HR, 0.87; 95% CI, 0.76-0.99; P = .03). QTc prolongation requiring a reduction in the dose of intravenous drug occurred in 31 patients (0.9%) receiving ranolazine compared with 10 patients (0.3%) receiving placebo. Symptomatic documented arrhythmias did not differ between the ranolazine (99 [3.0%]) and placebo (102 [3.1%]) groups (P = .84). No difference in total mortality was observed with ranolazine compared with placebo (172 vs 175; HR, 0.99; 95% CI, 0.80-1.22; P = .91). Conclusions The addition of ranolazine to standard treatment for ACS was not effective in reducing major cardiovascular events. Ranolazine did not adversely affect the risk of all-cause death or symptomatic documented arrhythmia. Our findings provide support for the safety and efficacy of ranolazine as antianginal therapy. Trial Registration clinicaltrials.gov Identifier: NCT00099788 相似文献