1.Tumor segmentation of brain MRI with adaptive bandwidth mean shift.
Journal of Biomedical Engineering 2014;31(5):1001-1010
In order to get the adaptive bandwidth of mean shift to make the tumor segmentation of brain magnetic resonance imaging (MRI) to be more accurate, we in this paper present an advanced mean shift method. Firstly, we made use of the space characteristics of brain image to eliminate the impact on segmentation of skull; and then, based on the characteristics of spatial agglomeration of different tissues of brain (includes tumor), we applied edge points to get the optimal initial mean value and the respectively adaptive bandwidth, in order to improve the accuracy of tumor segmentation. The results of experiment showed that, contrast to the fixed bandwidth mean shift method, the method in this paper could segment the tumor more accurately.
Brain Neoplasms
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pathology
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Contrast Media
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Humans
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Magnetic Resonance Imaging
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Neuroimaging
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Skull
2.Research progress in mechanisms of opioids-induced respiratory depression
Xiaowen LIU ; Zhen LIU ; Jing ZHAO
Basic & Clinical Medicine 2017;37(3):422-426
Respiratory depression is a common adverse effect of opioids .Currently, the mechanisms and manage-ment of opioid-induced respiratory depression ( OIRD) are one of the research foci .OIRD arises from stimulation ofμ-opioid receptors in the pre-Botzinger complex and the Kolliker-Fuse neurons .Adenylyl cyclase , calcium chan-nels, and G-protein-gated inwardly rectifying potassium (GIRK) channels may be the key cellular signaling mecha-nisms of OIRD .
3.Effects of uremic serum on TGF-?_1 of human renal tubular epithelial cells
Haiyan LIU ; Xiaowen CHEN ; Huafeng LIU
Chinese Journal of Practical Internal Medicine 2000;0(11):-
10 000 u,5 000~10 000u and 10 000 u group,and the gene expression was slightly increased in molecular weight 5 000~10 000 u group,but no significant difference of gene expression and protein secretion in 10 000 u uremic toxin,through promoting the gene expression and protein excretion of TGF-?_1 of renal tubular epithelial cells in patients with chronic renal failure.
4.Effects of preconditioning and praeruptorine C on intracellular free calcium level and NO content in hypertrophied vascular smooth muscle cells with hypoxia
Manren RAO ; Wanbing LIU ; Xiaowen ZHANG
Chinese Journal of Pharmacology and Toxicology 2001;15(2):141-144
Effects of preconditioning(PC) and praeruptorine C(Pra-C) on intracellular free calcium level([Ca2+]i) and NO content in hypertrophied vascular smooth muscle cells (VSMC) with hypoxia were studied. ①The aorta VSMC of rats with renovascular hypertension induced by two-kidney-one-clip(2K1C) were isolated and cultured. Fura-2/AM was as a calcium fluorescent indicator. It was seen that Pra-C(20 mg*kg-1*d-1,ig, for 9 weeks from week 9 after 2K1C) and PC (3 cycles of 5 min pure N2 and 5 min 95%O2+5%CO2) antagonisted the elevated activities(higher [Ca2+]i) induced by KCl and norepinephrine in VSMC with hypo- xia (30 min pure N2). ② In hypertrophied VSMC stimulated by angiotensinⅡ, combination of Pra-C(10 μmol*L-1 for 24 h) and PC enhanced NO content to the normal level in hypertrophied VSMC with hypo- xia. The results suggest that combination of Pra-C and PC have cooperative protection for hypertrophied VSMC with hypoxia injury.
5.Development of portable negative pressure calibrator
Xiaowen LIU ; Yi GE ; Yuxia ZHANG
China Medical Equipment 2015;(6):19-20,21
Objective: Develop a kind of portable negative pressure calibrator by the design and implement of method. Methods:By the working principle of negative pressure sensor and gas flow sensor, the negative pressure aspirator realizes the calibration function and stability of the monitoring function of the pressure and flow. Results:Stating from the design concept, this portable negative pressure can satisfy the requirement of the quality control and test work. Conclusion:Guarantee the accuracy and efficiency in the clinical first aid and field battle when using attractor. This avoids attractor of iatrogenic injury accident caused by negative pressure fall off.
6.Guidance significance of sputum smear on sputum culture
Lingli GU ; Xiang LIU ; Xiaowen SHEN
International Journal of Laboratory Medicine 2014;(24):3406-3407,3412
Objective To understand the guidance significance of sputum smear on the sputum culture by comparing the micro-scopic detection results of sputum smear with the sputum culture results in 227 cases.Methods 227 cases of sputum specimen were collected for observing the character and smear staining by microscopy.These specimens were divided into the class A,B,C and D according to the standards and simultaneously conducted the culture.The relationship between smear and culture was analyzed.Reˉ sults Among 227 cases of sputum specimen,158 cases were qualified and accounted for 69.60%,and 69 cases were unqualified and accounted for 30.40%.Potential pathogens were detected in 128 cases,the positive detection rate was 56.39%,the positive detec-tion rate of qualified sputum specimens was 70.39% and which of unqualified sputum specimens was 28.00%.The coincidence rate of qualified sputum specimen smear results and the culture results was 72.78%.The positive rate of cytophagic bacteria in the qual-ified sputum specimens was 11.72%,in which 14 cases of cytophagic bacteria were the qualified class A sputum specimens with the positive rate of 16.67% and 5 cases of cytophagic bacteria were the class B sputum specimens with the positive rate of 6.76 %. Conclusion The sputum smear microscopic detection can provide the important information for the diagnosis and treatment of re-spiratory infections and the sputum smear has the important guiding significance for sputum culture.
7.Determination of emodin and rhein in Niuhuangjiedu Tablets by HPLC
Taiping LI ; Xiaowen WANG ; Dongquan LIU ;
Chinese Traditional Patent Medicine 1992;0(04):-
Objective: A HPLC method for determination of emodin and rhein in Niuhuangjiedu Tablets was established. Methods: The chromatographic conditions were listed below: Diamonisil ODS C 18 column, UV detector at 254nm of wavelength, a mobile phase of methanol water phosphate acid(720∶280∶1),and 1mL?min -1 of flow rate. The retention time of emodin was 8.49 min and that of rhein was 15.56min. Results: The calibration curves were linear for emodin within 0.469~1.407?g( r =0.9992) and for rhein within 0.3125~ 0.9375?g ( r = 0.9992). The recoveries were 98.2%( RSD =0.43%)for emodin and 98.4%( RSD =0.72%)for rhein, respectively. Conclusion: This method is simple and the separate result is satisfactory.
8.Analysis of the results of multifocal visual evoked potential examination in patients with anterior ischemic opticneuropathy before and after treatment
Xiangqin LIU ; Xiaowen GUO ; Lixia ZHOU
Chinese Journal of Ocular Fundus Diseases 2009;25(6):437-439
Objective To observe the results of multifocal visual evoked potential (mfVEP) examination in patients with anterior ischemic optic neuropathy (AION) before and ater treatment,and to probe its clinical significance.Methods A total of 90 patients (90 eyes) with AION were examined by mfVEP;the second-order reaction of mfVEP was analyzed.The reaction was divided into upper and lower hemi-field of visual field,or 1 / 4 quadrant visual field (superior nasal,inferior nasal,superior temporal,and inferior temporal).The sum of waves of each response was analyzed and the results in various regions were compared.The features of wave configuration was compared between the AION eyes and the contralateral eye,and between the AION eyes before and after treatment.Results The amplitude and latency of P-wave of mfVEP was 0.198±0.033 and 100.197±7.354 respectively in AION eyes before treatment,and was 0.271±0.024 and 98.567±6.794 in the contralateral eyes;the difference was significant (t=16.556,18.330;P<0.01).The amplitude and latency of P-wave of mfVEP was 0.229±0.016 and 100.104±10.603 respectively in AION eyes after treatment,which differed much from that before the treatment (t=13.649,8.858;P<0.01) and also from that of the contralateral eyes (t=13.649,8.858;P<0.01).Conclusions The amplitude and latency of P-wave of mfVEP may accurately reflect the recovery of local optic nerve damage in AION eyes before and after treatment with good repeatability.AION can be used as a new method for AION diagnosis and detection of the prognosis.
9.Correlativity of leptin,TNF-? with metabolic syndrome
Xiaowen ZHAO ; Hong QIAO ; Yan LIU
Chinese Journal of Practical Internal Medicine 2001;0(07):-
Objective To study the relation of leptin,TNF-? in serum of patients with metabolic syndrome and its components.Methods Test leptin and TNF-? level of residents over 20 years old in two communities in Harbin City,grouping case-control study base on the constitutive ratio of actual age.Results Leptin was associated with obesity,and the higher leptin levels,the higher risk of suffering from metabolic syndrome.The relationship between leptin levels and metabolic syndrome was affected by age and gender.The lower level of TNF-?,the higher risk of metabolic syndrome.The patients with lower level of TNF-? were 1.859 times more likely to suffer from disease compared with people with higher level.Conclusion The effects of high level of leptin are significant on metabolic syndrome,especially for old males,and are associated with obesity component.TNF-? is related to plasma glucose and blood presure,and is good for metabolic syndrome,but its biological mechenism should be researched continuously.
10.Successful treatment of severe hemorrhagic cystitis following allogeneic stem cell transplantation by selective embolization of bilateral internal iliac arteries
Xiaowen TANG ; Yizhi LIU ; Xiaoli ZHU
Chinese Journal of Organ Transplantation 2003;0(06):-
Objective To investigate the therapeutic value of embolization in severe hemorrhagic cystitis(HC) following allogeneic stem cell transplantation.Methods Six patients undergoing allogeneic stem cell transplantation developed severe HC with a median onset time of 33 days after transplantation.All these patients had been resistant to conservative managements and received the treatment of selective embolization of bilateral internal iliac arteries.Results Eight times of embolizations were performed for 6 patients.The HC was cured in 4 patients and the HC improved in 1 patient,yielding a response rate of 83 %.One patient didn't respond to this measure.For the patients with response,macroscopic hematuria disappeared 7 to 10 days after the treatments and microscopic hematuria vanished 20 to 30 days after the intervention therapy.Both procedures were tolerated well and no severe adverse effects were observed.Conclusions Selective embolization of internal iliac arteries seems to be a safe and effective treatment for severe HC.This measure can be proposed for patients undergoing refractory and persistent severe HC.