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find Keyword "frequency" 190 results
  • Abnormal spontaneous brain functional activity in adult patients with amblyopia: a resting-state functional magnetic resonance imaging study

    Amblyopia is a visual development deficit caused by abnormal visual experience in early life, mainly manifesting as defected visual acuity and binocular visual impairment, which is considered to reflect abnormal development of the brain rather than organic lesions of the eye. Previous studies have reported abnormal spontaneous brain activity in patients with amblyopia. However, the location of abnormal spontaneous activity in patients with amblyopia and the association between abnormal brain function activity and clinical deficits remain unclear. The purpose of this study is to analyze spontaneous brain functional activity abnormalities in patients with amblyopia and their associations with clinical defects using resting-state functional magnetic resonance imaging (fMRI) data. In this study, 31 patients with amblyopia and 31 healthy controls were enrolled for resting-state fMRI scanning. The results showed that spontaneous activity in the right angular gyrus, left posterior cerebellum, and left cingulate gyrus were significantly lower in patients with amblyopia than in controls, and spontaneous activity in the right middle temporal gyrus was significantly higher in patients with amblyopia. In addition, the spontaneous activity of the left cerebellum in patients with amblyopia was negatively associated with the best-corrected visual acuity of the amblyopic eye, and the spontaneous activity of the right middle temporal gyrus was positively associated with the stereoacuity. This study found that adult patients with amblyopia showed abnormal spontaneous activity in the angular gyrus, cerebellum, middle temporal gyrus, and cingulate gyrus. Furthermore, the functional abnormalities in the cerebellum and middle temporal gyrus may be associated with visual acuity defects and stereopsis deficiency in patients with amblyopia. These findings help explain the neural mechanism of amblyopia, thus promoting the improvement of the treatment strategy for amblyopia.

    Release date:2022-10-25 01:09 Export PDF Favorites Scan
  • Radiofrequency Volumetric Tissue Reduction in the Treatment of Sleep Disordered Breathing: A Systematic Review

    Objective To evaluate the effectiveness ofradiofrequency volumetric tissue reduction (RFVTR) in the treatment of sleep disordered breathing (SDB ). Methods We searched The Cochrane Central Register of Controlled Trials (Issue 1, 2005), MEDLINE (1966 to Apr. 2005), EMBASE (1989 to Apr. 2005), CINAHL (1982 to Dec. 2000), VIP (1989 to Dec. 2004) , CJFD (1979 to 2005), WANFANG DATA (1977 to 2004) , and CBMdisc (1978 to 2005). The bibliographies of all papers retrieved in full text form and relevant narrative reviews were searched for additional publications. All randomized controlled clinical trials (RCT) or quasi-randomized controlled trials (quasi-RCT) or prospective cohort studies of RFVTR alone or in combination with other treatments compared with placebo or other treatments were included. Data were extracted independently from the trial reports by the two authors. Meta-analysis was performed using RevMan software. Results There were 11 studies including 540 patients met the inclusion criteria for this review, among which five were RCTs, six were prospective cohort studies, and all trials were of lower methodological quality. RFVTR showed benefit over placebo in apnea index (AI), but this benefit was not seen in other polysorrmography (PSG) parameters, symptom and quality of life, psychomotor vigilance pain, swallowing difficulty and adverse events. Compared with continuous positive airway pressure (CPAP), uvulopalatopharyngoplasty (UPPP) and laser assisted uvulopalatoplasty (LAUP) , RFVTR was more effective in psychomotor vigilance pain and swallowing difficulty, but this effect was not seen in PSG parameters, symptom and quality of life. Conclusions RFVTR is more effective than placebo in AI improvement and other treatments in decreasing postoperative pain and other adverse events ; but this benefit was not seen in improving quality of sleeping and life. More well-designed randomized trials need to be conducted to identify the effectiveness and the influence on effectiveness of severity and frequency of treatment.

    Release date:2016-09-07 02:25 Export PDF Favorites Scan
  • Comparative Study on Primary Journals Titled "Evidence-Based"

    Objective To compare articles published in global primary journals titled “evidence-based” via bibliometric analysis in order to provide suggestion for evidence-based research and development of related journals. Methods We searched electronic databases to retrieve global primary journals titled “evidence-based”, and collected their impact factors, article click, download and citation frequency through the journal’s website and related citation databases. Results Three English and 4 Chinese primary journals titled “evidence-based” met the inclusion criteria. (1) Citation frequency: Evidence-Based Complementary amp; Alternative Medicine and Worldviews on Evidence-Based Nursing were indexed by SCI with impact factor over 1 (5th and 13th in relevant subject category), and their immediacy index was about 7 times as much as that of Chinese journals (0.2 vs 0.03). Chinese Journal of Evidence-Based Pediatrics (CJEBP) had the highest impact factor among 4 Chinese journals (0.946, 23rd in the relevant subject category), while Chinese Journal of Evidence-Based Medicine had the highest immediacy index with 0.07; (2) Download frequency: Journal of Evidencebased Medicine (JEBM) had the highest download frequency per article in database (72 vs 23), but the website download frequencies per article of CJEBM and CJEBP were about 5 to 6 times as much as that of database; (3) Number of articles published: Two English journals published the fewest articles but with the highest impact factors. Chinese Journal of Evidence-Based Medicine had the 2nd highest impact factor although published the most articles, as well as the highest download frequency and immediacy index among the 4 Chinese journals. It suggested that there was no direct relationship between the number of the published articles and the impact factor of a journal. Conclusion The impact of English journals is better than that of Chinese journals. CJEBM and CJEBP are the top 2 ones among the Chinese journals with open access websites. The selection of articles should be driven by readers’ demand, and the impact of journals could be improved by online publication with open access.

    Release date:2016-09-07 11:23 Export PDF Favorites Scan
  • Impact of Ultrasound-Guided Acetic Acid Hypertonic Saline Solution Injection on Radiofrequency Ablation Destructive Zone in Dog Liver

    Objective To investigate the impact of injection of acetic acid hypertonic saline solution (AHS) in dog liver during radiofrequency ablation (RFA) on its destructive zone. Methods RFAs were performed in dog livers by using LDRF-120S mutiple probe ablation system combining 50% acetic acid 5% hypertonic saline solution injection. Thirty healthy adult hybrid dogs were randomly divided into 5 groups (n=6). Group A: RFA was performed immediately after injection of 2 ml AHS; Group B: RFA was performed 5 min after injection of 2 ml AHS; Group C: RFA was performed immediately after injection of 4 ml AHS; Group D: RFA was performed 5 min after injection of 4 ml AHS; Group E: RFA was performed immediately after injection of 6 ml AHS. Results There were no significant differences in the mean initial impedance within 5 groups. The mean ablation times were different significantly among 5 groups (F=83.831, P<0.001). The mean ablation time was different significantly between any two groups by LSD-t analysis (P<0.001). The mean coagulation diameters were different significantly among 5 groups (F=53.488, P<0.001). The mean coagulation diameter of group E was the largest among 5 groups. Besides mean coagulation diameter was no significant difference between group D and E (Pgt;0.05), the mean coagulation diameter was different significantly between any two groups by LSD-t analysis (P<0.001). Obviously thrombus were shown in coagulation necrosis zone and nearly normal tissue with gordon amp; sweet. AHS spillage from the injection site occurred in group E. Four dogs died in group E within 14 d but no dog died in the other groups. Conclusion RFA is performed 5 min after injection of 4 ml AHS in dog liver produces the ideal ablation destructive zone.

    Release date:2016-09-08 11:49 Export PDF Favorites Scan
  • Bibliometric Analysis of Literatures on Evidence-Based Medicine in 2002

    Objective To investigate the hot topics of research on evidence-based medicine in 2002. Method To search MEDLINE for papers on evidence-based medicine published in 2002, identify high-frequency subject headings related to research on evidence-based medicine, and cluster the high-frequency subject headings according to rates they appeared in common papers. Results 545 papers, 1 554 subject headings, 30 high-frequency subject headings on evidence-based medicine, and nine clustering categories of high-frequency subject headings were identified through search. Conclusions Both high-frequency subject headings and their clustering categories suggested that “evidence-based practice guidelines and their innovation”, “evidence-based health research and health policy”, “methodology on systematic reviews and randomized clinical trials”, “method of evidence-based decision making and its application in various subjects”, were the hot topics of evidence-based medicine. They provided useful references for Chinese medical professionals to practice evidence-based medicine.

    Release date:2016-08-25 03:33 Export PDF Favorites Scan
  • Atrial septal defect with atrial fibrillation treated by one-stop radiofrequency ablation and transthoracic closure under total endoscopy: A case report

    Surgical treatment of atrial septal defect (ASD) mainly includes occlusion or repair under cardiopulmonary bypass. Surgical treatment of atrial fibrillation includes transcatheter radiofrequency ablation or Maze surgery under cardiopulmonary bypass. There are many treatments for ASD patients combined with atrial fibrillation, but each has its own advantages and disadvantages. We reported an ASD patient combined with atrial fibrillation treated by totally endoscopic "one-stop" radiofrequency ablation and simultaneous transthoracic ASD occlusion of atrial fibrillation, with good postoperative results.

    Release date:2023-05-09 03:11 Export PDF Favorites Scan
  • EXPRESSION OF TRANSFORMING GROWTH FACTOR β1 AND INSULIN-LIKE GROWTH FACTORⅠIN THE REGENERATED BONES AFTER LOW FREQUENCY MICROMOVEMENT

    Objective To investigate the expression of transforminggrowth factor β1(TGF-β1) and insulin-like growth factorⅠ(IGF-Ⅰ)in new bone after low frequency micromovement. Methods Fifteen female sheep from Shandong province were involved in the study and their bilateral tibias transversely osteotomized in the middle shafts with a defect of 2 mm.The hind limbs were fixed with unilateral external fixators connected to a controlled micromovement device. Ten days after osteotomy, one hind limb of each sheep randomlywas selected to perform micromovement at an amplitude of 0.25 mm and a frequency of 1 Hertz, 30 min a day for 4 weeks ( micromovement group). The other hindlimb served as the control group. Five sheep were sacrificed at 3,4 and 6 weeks after osteotomy, respectively, and specimens were harvested for detecting the expression of TGF-β1 and IGF-Ⅰby immunohistochemistry and RT-PCR. Results Immunohistochemistry: In the third postoperative week in the micromovement group, the expression of TGF-β1 was detected in different areas of new chondrocytes at the margin of callus, mainly in proliferating area, and IGF-Ⅰexpressed in osteoblasts at the margin of endochondral ossification area, calcified and mature chondrocytes and osteocytes. There was seldom expression ofIGF-Ⅰ and little expression of TGF-β1 in the corresponding area in the control one. In the 4th postoperative week in the micromovement group, theexpression of TGF-β1 diminished gradually with the mature of new bone and be located in extracellular matrix and osteoblasts around ossified areas; The expression ofIGF-Ⅰ reached the peak and be located mainly in osteoblasts of new bone surface, maturing osteocytes and calcifing osteoid. But there was little expression of them in the control group. In the sixth postoperative week in the micromovement group, there was a little expression of IGF-Ⅰ expression but little expression of TGF-β1; there was nearly no expression of them in the control group. In the micromovement group, the absorbance values of TGF-β1 at 3 and 4 weeksand of IGF-Ⅰat 3, 4 and 6 weeks were significantlyhigher than those in control group(P<0.05). RTPCR: In the third and fourth postoperative weeks in the micromovement group, there was higher expression of mRNA of TGF-β1 and TGF-I than those in control group; in the sixth postoperative week, the expression diminished gradually, but was higher than that in control group. The absorbance values of TGF-β1 at 3 and 4 weeks and IGF-Ⅰat 3, 4 and 6weeks were significantly higher than those of control group(P<0.05). Conclusion Low frequency and controlled micromovement in the early stage of the fracture healing can promote the expression of TGF-β1 and IGF-Ⅰ.They worked together to regulate the process of the endochondral ossification, while in the late stage the differentiation of osteocytes and mineralization of osteoid were regulated mainly by IGF-Ⅰ, which played an important role in regulating the cell biological behavior during micromovement.

    Release date:2016-09-01 09:26 Export PDF Favorites Scan
  • Study of Resonant Frequency in Diagnosing of Low Frequency Conductive Hearing Loss

    Objective To investigate the relationship of resonant frequency and low frequency conductive hearing loss. Methods Eighty- four participants were included, and tested by gold standard and resonant frequency respectively. Receiver operator characteristic (ROC) curve was used to explore the most appropriate cutoff point for diagnosing low frequency conductive hearing loss and Levene’s test was used to test the difference of the low frequency conductive hearing loss and normal hearing groups. Results The resonant frequencies of low conductive frequency hearing loss and normal hearing groups were different. The optimum cutoff points of resonant frequency were 850Hz and 1 050Hz. The resonant frequency range from 850Hz to 1 050Hz was considered normal. The test was powerful when the resonant frequency was lower than 850Hz. The test was powerless when the resonant frequency was higher than 1 050Hz. Conclusions Conductive hearing loss could be predicted from resonant frequency when it is lower than 850Hz. The test is powerless when the resonant frequency is higher than 1 050Hz. The resonant frequency could be affected by many factors, so ENT (ear, nose and throat) doctors and audiologists have to be careful about how to explain the results when the resonant frequency is higher than 1 050Hz.

    Release date:2016-09-07 02:25 Export PDF Favorites Scan
  • Clinical Analysis of Concomitant Mitral Valve Replacement and Bipolar Radiofrequency Ablation for Chronic AtrialFibrillation

    Objective To evaluate clinical results of concomitant mitral valve replacement (MVR) and modified maze procedure with Atricure bipolar radiofrequency for chronic atrial fibrillation (AF). Methods Clinical data of 59 patients with mitral valve diseases and chronic AF who underwent concomitant MVR and bipolar radiofrequency ablation in Subei People’s Hospital from June 2010 to September 2012 were retrospectively analyzed. There were 22 male and 37 female patients with their age of 29-71 (48±11) years. The AF duration was 1.2-26.0 (7.2±3.4) years. Preoperatively,there were 20 patients with New York Heart Association (NYHA) class Ⅱ,31 patients with NYHA class Ⅲ and 8 patients with NYHA class Ⅳ. There were 32 patients with moderate to severe mitral stenosis,9 patients with moderate to severe mitral regurgitation and 18 patients with combined mitral stenosis and regurgitation. There were 42 patients with tricuspid regurgitation. The left artial dimension was 39-98 (55.2±8.9) mm. Left atrial thrombus was found in 9 patients. Atricure bipolar radiofrequency system was used for right atrial ablation under normothermic cardiopulmonary bypass (CPB) with beating heart first,then for ablations of the left and right pulmonary vein orifices and left atrium under moderate hypothermia with heart arrest. MVR was performed after ablation procedures were completed. Amiodarone was routinely used postoperatively and patients were periodically followed up after discharge. Results There was no in-hospital death. CPB time was 65-180 (99±28)minutes,aortic cross-clamping time was 46-123 (69±17)minutes,and ablation time was 15-28 (21±4)minutes. Postoperatively,heart rhythm immediately changed to sinus rhythm (SR) in 44 patients,remained AF in 10 patients and atrial flutter in 1 patient. Temporary pacemaker was used for 4 patients with bradycardia (3 patients recovered SR and 1 patient remained AF later). Fifty-eight patients were followed up after discharge for 6-33 months,and 1 patient was lost during follow-up. Patients’ SR rate was 86.2 % (50/58),91.4% (53/58),89.7 % (52/58),84.6 % (33/39)and 71.4 % (5/7)at discharge,3 months,6 months,1 year and 2 years after discharge respectively. There was no thrombotic event during follow-up. Conclusion Concomitant MVR and modified maze procedure with Atricure bipolar radiofrequency is a safe procedure for chronic AF with good short-term results.

    Release date:2016-08-30 05:47 Export PDF Favorites Scan
  • How to do radiofrequency ablation for liver cancer

    Based on the experience of more than 10 000 times of radiofrequency ablation treatment and the clinical and basic research results of radiofrequency ablation treatment of liver cancer obtained during the period, the author shares the experience of radiofrequency ablation indication selection, preoperative preparation, concept of radiofrequency ablation and postoperative follow-up of liver cancer. The purpose is to explore how to improve the curative effect of RFA treatment for small liver cancer, and reduce local residue, recurrence, as well as relevant complications.

    Release date:2022-10-09 02:05 Export PDF Favorites Scan
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