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find Keyword "intensity" 56 results
  • The Application of High Intensity Focused Ultrasound in the Tumor Treatment

    bjectiveTo evaluate the efficacy and limits of high intensity focused ultrasound (HIFU) in tumor treatment. MethodsThe references about the application of HIFU in tumor treatment in recent years were reviewed.ResultsHIFU caused localized hyperthermia at predictable depth in a few seconds to make the tumor tissue coagulative necrosis without injuring surrounding tissue. HIFU treatment had the advantages of low morbidity, noninvasiveness, avoidance of systemic side effects, and repeatitiveness. However, the utilization of HIFU sometimes could be limited by some factors such as imaging technique, organ movement, incomplete tissue destruction, etc.ConclusionHIFU is a promising noninvasive therapy for tumor treatment, though there are lots of problems to be further studied.

    Release date:2016-08-28 05:10 Export PDF Favorites Scan
  • The Effectiveness Evaluation of Antibiotics Management by Applying PDCA Cycle Model

    ObjectiveTo analyze the effectiveness of PDCA cycle model in antibiotics management by comparison of antibiotics use before and after the use of PDCA in a tertiary hospital. MethodsProspective study was adopted to analyze the using rate of antibiotics in outpatients, emergent patients and inpatients between June 2011 and December 2013. ResultsThe reasonable antibiotics use was improved since the beginning of PDCA cycle model. The antibiotics using rates of outpatients were 33.00%, 29.09% and 19.31%, of emergent patients were 45.00%, 32.81% and 28.94%, and of inpatients were 71.00%, 57.76% and 53.28% in year 2011 (from June to December), 2012 (from January to December) and 2013 (from January to December) respectively. Meanwhile, ClassⅠ incision antimicrobial use also decreased and bacteria examination rate continuously increased during the last three years. As a consequence, patients' cost was reduced. ConclusionThe PDCA cycle model promotes the standardized management of clinical medication application.

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  • Quantitative Study on Angiogenesis Features of Human Lung Adenocarcinoma Xenografted into Nude Mouse Model Using Time-intensity Curve Parameters with Contrast Enhanced Ultrasonography

    This research is to explore the perfusion time-intensity curve parameters of a lung adenocarcinoma xenograft into nude mouse model with contrast enhanced ultrasonography (CEUS); and to investigate the angiogenesis features of tumor at different growth time. Twenty one lung adenocarcinoma xenografted nude mice were divided into three groups and inculcated with human lung adenocarcinoa. Time window for examining CEUS were respectively in 7-day, 14-day and 28-day. The perfusion parameters including rise time (RT), peak intensity (PI), area under the curve (AUC) of lung tumor were obtained on CEUS images by using off-line software Q lab. Immunohistochemically staining for CD34 was used to observe the microvessel density (MVD).The 7-day group had the highest AUC and PI; AUC and PI of 14-day and 28-day group decreased gradually (P < 0.05). RT was increased as tumor growth. In tumor with necrosis, AUC and PI of non-necrosis part were also larger than necrosis part (P < 0.05). Immunohistochemically staining for CD34 of all tumors reflected that the density of microvessels in necrosis tumor was significantly higher than those without necrosis (7.50±3.44 vs.12.44±5.74, P=0.034). Pearson correlation indicated that PI was positively related with MVD (r=0.668, P=0.008). Lung adenocarcinoma perfusion characteristic can be accessed from time-intensity curve parameters by using noninvasively and non-radiative contrast enhanced ultrasonography. Time-intensity curve parameters including AUC, PI and RT may reflect tumor angiogenesis.

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  • Analysis of Signal Intensity and Enhancement Patterns of Early Arterial Phase of Small Hepatic Nodular Lesions on MRI

     Objective To retrospectively assess the importance and imaging appearance of the signal intensity, the signal noise ratio (SNR), the contrast noise ratio (CNR) and enhancement patterns of early arterial phase in diagnosis and differential diagnosis of small hepatic nodular lesions on MRI.  Methods Conventional spin-echo T2W, 2D GRE T1W plain scan and Gd-enhanced 3D-VIBE multi-phasic (early arterial, late arterial and portal venous phase) acquisitions were performed for 68 consecutive patients with 102 lesions on MRI. Native T2W and 2D GRE T1W were acquired first, then 3D-VIBE fast scanning at early arterial, late arterial and portal venous phase respectively. The SNR, CNR, signal intensity and enhanced pattern of the nodular lesions appearances on plain scan and eariy arterial phase were carefully observed.  Results There were hyperintense in 102 (100%) lesions in T2W and hypointense in 95 (93.1%) lesions in T1W in plain scan. There were differences among the SNR, CNR of hepatic cyst, cavernous hemangioma, neoplasm metastasis and small hepatocellular carcinoma in T2W (P<0.05),the highest SNR and CNR of lesions were hepatic cyst. The SNR of small hepatocellular carcinoma and the CNR of hepatic cyst were highest in all the type diseases in T1W, there was significantly difference as compared with the other type diseases (P<0.05). The enhancement rate of small hepatic nodular lesions was 76.5% in early arterial phase. The enhancement rate of small hepatocellular carcinoma and hepatic metastasis were 100% and 87.9% respectively. The non-enhancement rate of hepatic cyst were 100%. The common enhancement patterns of early arterial phase were peripheral enhancement which were 36 lesions (35.3%). The even enhancement and uneven enhancement were 22 lesions (21.6%) and 20 lesions (19.6%) respectively.  Conclusion Qualitative and quantitative evaluation of MR signal intensity combined with the enhancement patterns of early arterial phase will help for qualitation and differential diagnosis of small hepatic nodular lesions on MRI.

    Release date:2016-09-08 10:57 Export PDF Favorites Scan
  • Improvement of different resistance training regimens on blood lipids and insulin resistance in patients with type 2 diabetes mellitus: a network meta-analysis

    Objective To assess the improvement of different resistance training regimens on blood lipid metabolism and insulin resistance in patients with type 2 diabetes mellitus (T2DM). Methods PubMed, ProQuest, Embase, Web of Science, China National Knowledge Infrastructure, Wanfang, and VIP databases were searched to collect randomized controlled trials of resistance training intervention to improve blood lipids and insulin resistance in patients with T2DM. The search time range was from the establishment of the databases to May 2023. Two reviewers assessed the risk of bias of the included studies using the Physiotherapy Evidence Database scale, and performed a network meta-analysis of the extracted data using Stata 16.0 software. Results In the end, 24 articles were included, and a total of 983 participants were enrolled. The result of network meta-analysis showed that high-frequency and moderate-intensity resistance exercise significantly improved the levels of insulin resistance [standardized mean difference=−1.71, 95% confidence interval (CI) (−2.75, −0.67)], triglycerides [weighted mean difference (WMD)=−0.27 mmol/L, 95%CI (−0.51, −0.04) mmol/L], and total cholesterol [WMD=−0.16 mmol/L, 95%CI (−0.20, −0.12) mmol/L], but had no significant effect on improving the level of high-density lipoprotein [WMD=0.05 mmol/L, 95%CI (−0.02, 0.11) mmol/L] or low-density lipoprotein [WMD=−0.20 mmol/L, 95%CI (−0.42, 0.03) mmol/L]. The results of cumulative probability ranking showed that high-frequency and moderate-intensity resistance exercise was the best in improving insulin resistance, triglycerides, high-density lipoprotein and low-density lipoprotein levels. Conclusion Based on current evidence, high-frequency and moderate-intensity resistance exercise may be the best resistance exercise regimen to improve insulin resistance and lipid metabolism in patients with T2DM.

    Release date:2024-02-29 12:03 Export PDF Favorites Scan
  • Application of Pencil Beam Model Based on Point Kernel in Intensity Modified Radiatioin Therapy

    In this paper, a method for dose calculation with pencil beam kernels constructed by point kernel superposition was proposed to accelerate the dose calculation during intensity optimization iteration. With this method, the direct aperture optimization method can be integrated in the planning system based on point kernel convolution/superposition model. The dose calculation time was also reduced during the iteration. From the result of the phantom and clinical patient data test, it was concluded that this method could be used for the intensity optimization of iteration dose calculation as the satisfied precision due to the optimization result coherence obtained. By implementing the method in the planning system product based on point kernel convolution/superposition model, a lot of additional research and development works for the pencil beam dose calculation model as well as the product maintenance cost can be avoided.

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  • Development of a high intensity focused ultrasound device for bio-samples preparation

    A miniaturized, low-cost high-intensity focused ultrasound device is developed for the problems of cross-contamination and uneven sample fragmentation in conventional ultrasound devices. This device generates ultrasonic waves through a concave spherical self-focusing piezoelectric ceramic piece, and creates a cavitation effect in the focusing area to achieve sample fragmentation. The feasibility of the device is demonstrated by physical simulation, then a driving circuit with adjustable power is designed and manufactured to generate 0 ~ 22.4 W acoustic power, and finally paraffin-embedded sample dewaxing experiments are performed to verify the validation of the device. The experimental results show that the dewaxing efficiency and safety of the high-intensity focused ultrasound device is significantly better than those of traditional chemical methods, and this device is comparable with commercial ultrasonic instruments. In summary, the high-intensity focused ultrasound device is expected to be applied in automated nucleic acid extraction and purification equipment and has a broad application prospect in the field of sample pre-processing.

    Release date:2024-04-24 09:40 Export PDF Favorites Scan
  • Efficacy of high-intensity interval training on weight loss and blood lipid metabolism with overweight or obesity: a meta-analysis

    ObjectiveTo systematically review the intervention effects of high-intensity interval training (HIIT) on weight loss and blood lipid metabolism in overweight/obese populations. MethodsThe computer conducted searches in the PubMed, Embase, Cochrane Library, Web of Science, CNKI, and WanFang Data database to collect randomized controlled trials (RCTs) related to HIIT and weight loss, fat reduction, and blood lipid metabolism in overweight/obese populations. The search was conducted from the inception of the databases to March 31, 2023. Two researchers independently conducted literature screening and data extraction. After evaluating the risk of bias of the included studies, a meta-analysis was performed using RevMan 5.4 software. ResultsA total of 19 RCTs, involving 595 overweight/obese participants, were included. The meta-analysis results showed that compared wtih the control group, HIIT interventions effectively reduced body weight (MD=−2.63, 95%CI −4.04 to −1.23, P<0.05), BMI (MD=−1.21, 95%CI −1.95 to −0.48, P<0.05), Fat% (MD=−1.66, 95%CI −2.28 to −1.04, P<0.05), TG (MD=−0.13, 95%CI −0.25 to −0.01, P=0.04), HDL (MD=0.14, 95%CI 0.05 to 0.23, P<0.05), and LDL (MD=−0.26, 95%CI −0.39 to −0.13, P<0.05) levels but did not improve TC (MD=−0.15, 95%CI −0.36 to 0.06, P=0.15) levels. ConclusionHIIT intervention can effectively improve body weight, BMI, Fat%, TG, HDL, and LDL levels in overweight/obese populations, particularly showing a more pronounced improvement in lipid profiles among overweight/obese adolescents, but it does not reduce TC levels. This study demonstrates that HIIT may be an effective strategy to assist in weight loss and prevent cardiovascular diseases in overweight/obese populations, with potential for broader application.

    Release date:2024-03-13 08:50 Export PDF Favorites Scan
  • Simulation research of respiratory monitoring with magnetic detection electrical impedance tomography

    In order to explore the feasibility of applying magnetic detection electrical impedance tomography (MDEIT) on respiratory monitoring, aiming at the forward problem of magnetic detection electrical impedance tomography, we calculated the electric potential and current density distribution inside the imaging object by using the finite element method. We then got magnetic induction intensity outside the object at the end of exhaling and inhaling according to Biot-Savart's law. The results showed that the magnetic induction intensity at the end of inhaling was 8.875%, less than that at the end of exhaling. By the simulation results, we could understand the difference of magnetic induction intensity value surrounding the lung at the end of exhaling and inhaling due to the change of lung volume and electrical conductivity distribution better. Our research laid the foundation for the late image reconstruction and clinical disease detection.

    Release date:2017-04-01 08:56 Export PDF Favorites Scan
  • Differential diagnosis significance of 3.0T MRI united-sequence examination forbenign and malignant breast lesions

    Objective To explore the differential diagnosis significance of 3.0T MRI united-sequences examination in the diagnosis of benign and malignant breast lesions. Methods A total of 67 breast lesions of 59 patients were collected prospectively, which be treated at the Sichuan Provincial People’s Hospital during July 2015 to January 2017. All patients were underwent bilateral breast 3.0T magnetic resonance plain scan, diffusion weighted imaging, and dynamic enhanced scan successively before surgical operation. Analysis of morphological features of the benign and malignant breast lesions, the time-signal intensity curve (TIC), the apparent diffusion coefficient (ADC), and the combination diagnosis of them were performed. Results Of all 59 patients, 67 lesions were confirmed by histopathology, including 18 benign lesions and 49 malignant lesions. The morphological features (including margin, shape, border, and evenness), the types of TIC of dynamic enhancement, and ADC value between the benign lesions and malignant lesions were statistically significant (P<0.05). The sensitivity and specificity of Fischer scoring system was 89.8% (44/49) and 61.1% (11/18) respectively. The sensitivity and specificity of TIC types was 83.7% (41/49) and 77.8% (14/18) respectively. The diagnostic threshold of ADC value was 1.012×10–3 mm2/s, with the sensitivity and specificity for the diagnosis was 91.8% (45/49) and 83.3% (15/18) respectively. The sensitivity and specificity of the combination of Fischer scoring system and TIC type for diagnosis between benign and malignant breast lesions was 95.9% (47/49) and 72.2% (13/18) respectively. The sensitivity and specificity of the combination of Fischer scoring system, TIC type, and ADC value for benign and malignant breast lesions was 98.0% (48/49) and 83.3% (15/18) respectively. Conclusion The combination of Fischer scoring system, TIC type, and diffusion-weighted imaging for the differential diagnosis between benign lesions and malignant lesions was more effective than single imaging method.

    Release date:2018-07-18 01:46 Export PDF Favorites Scan
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