A primary study on Processing in X - ray inspection of spot weld for aluminum alloy spot welding,in- cluding for background simulation,acquisition of ideal binary image, and extraction and identifi- cation of defec...A primary study on Processing in X - ray inspection of spot weld for aluminum alloy spot welding,in- cluding for background simulation,acquisition of ideal binary image, and extraction and identifi- cation of defect features was presented.展开更多
Objectives To compare the different patterns of coronary artery calcification (CAC) in acute and chronic coronary syndromes utilizing electron beam computed tomography. Background Pathologic, angiographic, and intraco...Objectives To compare the different patterns of coronary artery calcification (CAC) in acute and chronic coronary syndromes utilizing electron beam computed tomography. Background Pathologic, angiographic, and intracoronary ultrasound studies revealed sharp differences in the plaque morphology between patients with acute versus chronic coronary syndromes. Whether there are different patterns of coronary artery calcification in patients with stable angina pectoris (SAP) and in those with unstable angina pectoris (UAP) or acute myocardial infarction (AMI), however, remains unclear. Methods Two hundred and sixty - four patients, including 67 with SAP, 94 with UAP and 103 with AMI were studied with electron beam computed tomography for analysis of coronary artery calcification and with selective coronary angiography for determination of atherosclerotic lesions. CAC prevalence and calcium score were compared among three groups, and relation of CAC to the severity of atherosclerotic disease in the SAP and UAP patients was separately analyzed. Results Prevalence of CAC was 100 % in the SAP patients, significantly higher than the 87. 23 % in UAP patients and 86. 41 % among the patients with AMI ( P < 0. 05) . More patients and arteries in the SAP group had severe forms of calcium than those in the UAP and AMI group ( P < 0. 01), and the mean LN [CS + 1] (natural logarithm transformation of calcium score) of the SAP patients was much greater than that of the UAP and AMI patients (P < 0.001). The distribution of vessels with various CAC by luminal stenosis was different between SAP and UAP patients. The average CAC extent of the infarct - related arteries was less severe than that of the noninfarct - related arteries. Conclusions U-tilizing electron beam computed tomography, we demonstrated that there exist different patterns of coronary artery calcification in patients with acute versus chronic coronary syndromes, which may provide insight into the differences observed in the clinical and pathologic development between these two types of coronary artery disease.展开更多
AIM To clarify the association of malignancy with mesenteric panniculitis-like changes on computed tomography(CT).METHODS All abdominal CT scans performed at North Shore University HealthS ystem showing mesenteric pan...AIM To clarify the association of malignancy with mesenteric panniculitis-like changes on computed tomography(CT).METHODS All abdominal CT scans performed at North Shore University HealthS ystem showing mesenteric panniculitis from January 2005 to August 2010 were identified in the Radnet(Rad Net Corporation, Los Angeles, CA) database. Patients with a new or known diagnosis of a malignancy were included for this analysis. Longitudinal clinical histories were obtained from electronic medical records.RESULTS In total, 147794 abdominal CT scans were performed during the study period. Three hundred and fiftynine patients had mesenteric panniculitis(MP)-like abnormalities on their abdominal CT. Of these patients, 81 patients(22.6%) had a known history of cancer at the time of their CT scan. Nineteen(5.3%) had a new diagnosis of cancer in concurrence with their CT, but the majority of these(14/19, 74%) were undergoing CT as part of a malignancy evaluation. Lymphomas were the most common cancers associated with MPlike findings on CT(36 cases, 36%), with follicular lymphoma being the most frequent subtype(17/36). A variety of solid tumors, most commonly prostate(7) and renal cell cancers(6) also were seen. CT follow up was obtained in 56 patients. Findings in the mesentery were unchanged in 45(80%), worsened in 6(11%), and improved in 5 patients(9%). Positron emission tomography(PET) scans performed in 44 patients only showed a positive uptake in the mesenteric mass in 2 patients(5%). CONCLUSION A new diagnosis of cancer is uncommon in patients with CT findings suggestive of MP. MP-like mesenteric abnormalities on CT generally remain stable in patients with associated malignancies. PET scanning is not recommended in the evaluation of patients with mesenteric panniculitis-like findings on CT.展开更多
Background: In 2010, the International Atomic Energy Agency launched the “3A’s campaign” as an effective tool for primary cancer prevention. In 2011, the American Association of Physicists in Medicine recommended t...Background: In 2010, the International Atomic Energy Agency launched the “3A’s campaign” as an effective tool for primary cancer prevention. In 2011, the American Association of Physicists in Medicine recommended the size specific dose estimate (SSDE). Objectives: To audit doses of Coronary CT Angiography (Coronary CTA) in tertiary care referral center. Methods: We reviewed 998 consecutive Coronary CTA (from 2007 to 2012). Doses (CTDIvol mGy), DLP (mGy*cm), effective dose (DLP*0.014, mSv) were on-line archived. SSDE was estimated retrospectively. Appropriateness score was evaluated for exams performed from the 2010. Results: Overall median dose per Coronary CTA was 49.7 mGy for CTDIvol, 55.5 mGy for SSDE, 994.96 mGy*cm for DLP, 13.9 mSv for effective dose. Median DLP decreased over time (1452.94 in 2007, 1605.56 in 2008, 1113.49 in 2009, 759.99 in 2010, 448.61 in 2011 and 497.88 mGy*cm in 2012, p < 0.0001). SSDE was proportional to the size dependent factor (SDF);in patients with SDF > 1 (88%) CTDIvol underestimated SSDE (48.49 vs 57.19 mGy), whilst in patients with SDF < 1 (12%) CTDIvol overestimated SSDE (56.46 vs 50.3 mGy). Scans were appropriate in 58%, uncertain in 24%, and inappropriate in 18% of cases. Doses were similar in appropriate, uncertain or inappropriate examinations and in excellent-to-good (81%) vs. sufficient-to-poor (19%) image quality exams. Conclusions: Coronary CTA reference doses can be very misleading. SSDE can allow individual technique optimization. The dose is similar in appropriate and inappropriate examinations, and unrelated to image quality. The rate of inappropriate examinations is still too high even after dissemination of guidelines.展开更多
Objective: To develop and validate a computed tomography(CT)-based radiomics nomogram for predicting human epidermal growth factor receptor 2(HER2) status in patients with gastric cancer.Methods: This retrospective st...Objective: To develop and validate a computed tomography(CT)-based radiomics nomogram for predicting human epidermal growth factor receptor 2(HER2) status in patients with gastric cancer.Methods: This retrospective study included 134 patients with gastric cancer(HER2-negative: n=87;HER2-positive: n=47) from April 2013 to March 2018, who were then randomly divided into training(n=94) and validation(n=40) cohorts. Radiomics features were obtained from the CT images showing gastric cancer. Least absolute shrinkage and selection operator(LASSO) regression analysis was utilized for building the radiomics signature. A multivariable logistic regression method was applied to develop a prediction model incorporating the radiomics signature and independent clinicopathologic risk predictors, which were then visualized as a radiomics nomogram. The predictive performance of the nomogram was assessed in the training and validation cohorts.Results: The radiomics signature was significantly associated with HER2 status in both training(P<0.001) and validation(P=0.023) cohorts. The prediction model that incorporated the radiomics signature and carcinoembryonic antigen(CEA) level demonstrated good discriminative performance for HER2 status prediction,with an area under the curve(AUC) of 0.799 [95% confidence interval(95% CI): 0.704-0.894] in the training cohort and 0.771(95% CI: 0.607-0.934) in the validation cohort. The calibration curve of the radiomics nomogram also showed good calibration. Decision curve analysis showed that the radiomics nomogram was useful.Conclusions: We built and validated a radiomics nomogram with good performance for HER2 status prediction in gastric cancer. This radiomics nomogram could serve as a non-invasive tool to predict HER2 status and guide clinical treatment.展开更多
AIM To recognize the characteristic findings of non pathologic perfusion defects with CT arterial portography (CTAP) and nonpathologic enhancement found in CT hepatic arteriography (CTHA). METHODS The manifestatio...AIM To recognize the characteristic findings of non pathologic perfusion defects with CT arterial portography (CTAP) and nonpathologic enhancement found in CT hepatic arteriography (CTHA). METHODS The manifestations of nonpathologic perfusion defects with CTAP and non pathologic enhancement found in CTHA were analyzed in 50 patients with primary hepatocellular carcinoma. RESULTS The false positive rate of perfusion defects detected in CTAP was 15 1%. The shapes of perfusion defects were peripheral wedge, small, round, and patchy. The occurrence rate of non pathologic enhancement found in CTHA was 22 0%. The shapes of non pathologic enhancement were small, round, irregular, and wedge. CONCLUSION There was a high frequency of non pathologic perfusion defects detected with CTAP and non pathologic enhancement found in CTHA. The simultaneous use of both procedures may help decrease the false positive rate, and increase the veracity of diagnosis for hepatocellular carcinoma.展开更多
CT guided percutaneous transthoracic fine needle aspiration biopsy (PTFNAB) was performed in twenty four sputum negative cases of small peripheral pulmonary lesions smaller than 2 cm in diameter, which are not easi...CT guided percutaneous transthoracic fine needle aspiration biopsy (PTFNAB) was performed in twenty four sputum negative cases of small peripheral pulmonary lesions smaller than 2 cm in diameter, which are not easily diagnosed or accessible to fibrobron choscopes. After thin slide scanning and localization with Somatom DR H computed tomography, pulmonary nodules were biopsied with a 20 Gauge needle guided by a ruler specially designed. Biopsy materials were used for cyto and histopathologic examinations. The diagnosis accuracy of biopsy was evaluated by the result of postoperative pathology and/or follow up for 2 years. Sixteen pulmonary lesions were proved to be malignant and 8 were benign. The sensitivity was 75.0% (12/16), speciti vity 100% (8/8) and accuracy 83.3% (20/24) according to cytopathology and 87.5% (14/16), 100% (8/8), 91.7% (22/24) by histopathology, respectively. Two cases of early stage peripheral lung cancer were detected and proved by operation. CT guided PTFNAB is safe and quick for diagnosis with high accuracy for small peripheral pulmonary lesions which are usually negative in sputum examination and bronchoscopy. PTFNAB should be routinely used in the diagnosis of lung neoplasms.展开更多
Microstructural change of YBaCuO film/YSZ substrate with and without proton irradiation has been studied by scanning electron microscope and X- ray diffraction techniques. Structural analysis has shown that conversion...Microstructural change of YBaCuO film/YSZ substrate with and without proton irradiation has been studied by scanning electron microscope and X- ray diffraction techniques. Structural analysis has shown that conversion from tetragonal to orthorhombic phases, reduction of nonsuperconducting phase and preferential rearrangement of crystal grains are all favorable to the improvement of superconductivity in the YBaCuO film supported by YSZ substrate by proton beam bombardment.展开更多
This paper summarizes the new developments in the study of barium rare-earth fluor-carbonate mineral structures .The second order superstructure of cebaite -(Ce ) was solved by using high power X-ray single crystal di...This paper summarizes the new developments in the study of barium rare-earth fluor-carbonate mineral structures .The second order superstructure of cebaite -(Ce ) was solved by using high power X-ray single crystal diffractometer . Five kinds of coordination forms were found . All atoms in the cell , including C and F , were properly located . In the process of study in a cordylite-(Ce ), a new mineral was discovered , whose chemical formula is (Ca0.5□0.5) BaCe2 (CO3)4F . It is isostructural with baiyuneboite - (Ce ), but different in composition (Na in baiyuneboite- (Ce ) is substituted by Ca disorderly ) . On the basis of the studies a proposal to re-define cordylite-(Ce )as a mineral group name is put forth by the authors . Finally a new type of twinning of huanghoite-(Ce ) was found on the systematical absence of diffraction data by means of a single crystal diffractometer .展开更多
随着鼻窦CT诊断和鼻内镜诊疗技术的发展,大量鼻部疾病导致的头痛得以治愈。根据2004年国际头痛协会的分类,鼻源性头痛的第二种类型——黏膜接触点性头痛(mucosa contact point headache),因为缺少典型的鼻部症状,而分散就诊于其...随着鼻窦CT诊断和鼻内镜诊疗技术的发展,大量鼻部疾病导致的头痛得以治愈。根据2004年国际头痛协会的分类,鼻源性头痛的第二种类型——黏膜接触点性头痛(mucosa contact point headache),因为缺少典型的鼻部症状,而分散就诊于其他学科,长期得不到合理诊疗。我们近期总结了多例临床上没有典型的鼻部症状,而是以各种类型的头痛为主诉就诊于神经内科等专科的患者,经过会诊筛查,确诊为鼻源性黏膜接触点性头痛,通过鼻内镜手术治愈。其中包括1组女性患者,长期被误认为是月经前期头痛,通过治疗证明是黏膜接触点性头痛的一种特殊存在形式,撰文总结如下。展开更多
Objective:To investigate the rol e of CT scanning in diagnosing severe acute respiratory syndrome(SARS). Methods: One hundred and twelve times of spiral CT scanning, 106 t imes on the chest with standard pulmonary and...Objective:To investigate the rol e of CT scanning in diagnosing severe acute respiratory syndrome(SARS). Methods: One hundred and twelve times of spiral CT scanning, 106 t imes on the chest with standard pulmonary and mediastinal window, 5 on the brain and once on the abdomen, were performed in 82 patients (37 males and 45 females ) of SARS. Results: Bilateral shadows showed in 66 patients (80.48%) and unil ateral shadow in 16 (19.52%). The lung CT findings were sub pleural focal con solidation in 26 patients (31.70%), flaky cloudy opacity in 53 (64.63%), large a rea consolidation in 9 (10.97%), ground glass blurry shadow in 31 (37.80%), a lveolar substantive shadow in 14 (17.07%) and interstitial changes in 16 (19.51% ). The pulmonary CT signs of SARS were relatively characterized by: (1) The lesi ons tending to multiply occur, mostly to be bilaterally distributed and commonly involved in the lower lung field. (2) The lung shadows mostly showed as sub pleural focal consolidation, flaky cloudy shadow, large area consolidation, grou nd glass blurry shadow, and often accompanied with signs of broncho inflat ion. (3) Having opacified nodular shadows in the alveolar cavities. (4) Rapid pr ogressions or changes on the size, amount, and distribution of the lesions likel y to be found in dynamic observation of chest X ray and CT scanning, i.e., ma rkedly dynamic changes found within 24 to 48 hrs. Lesions with these characteris tics may be recognized as pulmonary changes possibly induced by SARS. Complicati ons were found in 6 patients (7.31%), including tuberculosis of lung and brain a ccompanied with pneumomediastinum in one patient, secondary infection of lung in 2, pneumothorax in 1, pulmonary fungus in 1, and pyothorax in 1.Conclusion: CT scanning is a sensitive method for diagnosis of SAR S, by which more accurate assessment of the abnormal changes of lung and occurre nce of complications in SARS patients can be made.展开更多
Objective:To examine CT and pathologic presentations of the periphery of hepatocelllar carcinoma (HCC) by using in vivo liver specimens from orthotopic liver transplantation (OLT) and to see whether there is any corre...Objective:To examine CT and pathologic presentations of the periphery of hepatocelllar carcinoma (HCC) by using in vivo liver specimens from orthotopic liver transplantation (OLT) and to see whether there is any correlation between them. Materials and Methods:Forty-two patients with HCC confirmed by pathology and liver transplantation were included. Plain CT scan covering the whole liver was done, followed by arterial and portal venous phase scanning. The delay time was 25 s and 60 s after injection of contrast medium. Fresh liver samples were evaluated, sliced and stained with HE and the standard immunoperoxidase method using facterⅧrelated antigen (F8RA) monoclonal antibody to study CT presentation of the periphery of tumor and compare them with pathologic findings. Results: (1) Tumors with clear boundaries on CT scan reflected the presence of tumor capsules in pathologic sections. Most tumors with unclear boundaries had no capsules and grew in an invasive pattern; (2) Tumors with unclear boundaries or high density on dynamic enhancement usually had abundant newborn vessels in the periphery and were poorly differentiated, while those with low density had few newborn vessels and were well differentiated; (3) When microvessel density (MVD) was>30, the occurrence of intrahepatic daughter foci was higher. Conclusion: (1) CT morphologic classification of the HCC periphery can well reflect the intactness of tumor capsules, which is helpful for preoperative assessment of tumor infiltration and cancer cell grading; (2) CT enhancement presentation of the HCC periphery in arterial and portal phases may reflect pathologic changes and help predict the prognosis at large.展开更多
The launderability of wool fabrics treated by nano finoshing agent influences directly the functional endurance of he treated wool fabric. In order to investigate the effect of wool fibers surface modification on the ...The launderability of wool fabrics treated by nano finoshing agent influences directly the functional endurance of he treated wool fabric. In order to investigate the effect of wool fibers surface modification on the functional erdurance of nano finishinp wool fibers, in this paper, for the first time wool fibers were chemically modified by using NaClO aqueous and KMnO4 aqueous, and then chemically modified wool fibers and native wool fibers were treated using nano ZnO finishing agent, respectively. The launderability of wool fibers treated by nano finishing agent was investigated. The experimental results show that the chemically modified wool fibers have a good launderaility after being treated by nano ZnO finishing agent treating. The surface morphologies of wool fibers were observed by using SEM. It is got that there is a strong adbesion between nano ZnO and wool surface through XPS analysis.展开更多
Objectives To evaluate the ability of CT pleurography (CTP) in detecting minor pleural lesions in patients with pleural effusion and to assess its value in distinguishing malignant from benign pleural lesions. Method...Objectives To evaluate the ability of CT pleurography (CTP) in detecting minor pleural lesions in patients with pleural effusion and to assess its value in distinguishing malignant from benign pleural lesions. Methods A prospective study of 50 patients with pleural effusion was conducted using conventional CT and CTP. CT scan was run after injecting an appropriate amount of contrast medium into the pleural cavity. Results In 24 patients, all lesions detected by conventional CT were demonstrated by CTP. In 13 of 24 patients, CT pleurography detected additional lesions. In 20 of 26 patients with negative findings on conventional CT, CTP was capable of demonstrating the presence of pleural lesions. The sensitivity, specificity and accuracy of detecting pleural lesions were 25%, 100% and 30% for conventional CT, 86%, 100% and 87% for CTP, respectively. Conclusion CTP is superior to conventional CT in detecting and for the differential diagnosis benign and malignant pleural lesions.展开更多
Objective To investigate the clinical and imaging characteristics of severe acute respiratory syndrome (SARS), and to study their relationship Methods Forty six SARS confirmed patients were admitted to our hospi...Objective To investigate the clinical and imaging characteristics of severe acute respiratory syndrome (SARS), and to study their relationship Methods Forty six SARS confirmed patients were admitted to our hospital from February to April, 2003 X ray examination documents were available in all cases and chest CT scanning was acquired in 6 cases, which were analyzed retrospectively, accompanied by their clinical features Results Fever was found in 97 8% of the patients Clinical symptoms were mild, but X ray and CT findings were distinct CT scanning demonstrated ground glass like lesions and large patchy exudation and consolidation at the early stage in 6 cases Different findings on radiography and CT were related to the different phases of the disease After treatment, most lesions were absorbed completely, but slowly in patients with multi lobe consolidation and/or extensive interstitial infiltration Conclusion Special clinical and imaging findings could be found in SARS cases The prognosis of SARS patients is related to the degree of lesions detected by radiography and CT展开更多
文摘A primary study on Processing in X - ray inspection of spot weld for aluminum alloy spot welding,in- cluding for background simulation,acquisition of ideal binary image, and extraction and identifi- cation of defect features was presented.
文摘Objectives To compare the different patterns of coronary artery calcification (CAC) in acute and chronic coronary syndromes utilizing electron beam computed tomography. Background Pathologic, angiographic, and intracoronary ultrasound studies revealed sharp differences in the plaque morphology between patients with acute versus chronic coronary syndromes. Whether there are different patterns of coronary artery calcification in patients with stable angina pectoris (SAP) and in those with unstable angina pectoris (UAP) or acute myocardial infarction (AMI), however, remains unclear. Methods Two hundred and sixty - four patients, including 67 with SAP, 94 with UAP and 103 with AMI were studied with electron beam computed tomography for analysis of coronary artery calcification and with selective coronary angiography for determination of atherosclerotic lesions. CAC prevalence and calcium score were compared among three groups, and relation of CAC to the severity of atherosclerotic disease in the SAP and UAP patients was separately analyzed. Results Prevalence of CAC was 100 % in the SAP patients, significantly higher than the 87. 23 % in UAP patients and 86. 41 % among the patients with AMI ( P < 0. 05) . More patients and arteries in the SAP group had severe forms of calcium than those in the UAP and AMI group ( P < 0. 01), and the mean LN [CS + 1] (natural logarithm transformation of calcium score) of the SAP patients was much greater than that of the UAP and AMI patients (P < 0.001). The distribution of vessels with various CAC by luminal stenosis was different between SAP and UAP patients. The average CAC extent of the infarct - related arteries was less severe than that of the noninfarct - related arteries. Conclusions U-tilizing electron beam computed tomography, we demonstrated that there exist different patterns of coronary artery calcification in patients with acute versus chronic coronary syndromes, which may provide insight into the differences observed in the clinical and pathologic development between these two types of coronary artery disease.
基金Supported by An unrestricted grant from the Keyser Family Fund(partly)
文摘AIM To clarify the association of malignancy with mesenteric panniculitis-like changes on computed tomography(CT).METHODS All abdominal CT scans performed at North Shore University HealthS ystem showing mesenteric panniculitis from January 2005 to August 2010 were identified in the Radnet(Rad Net Corporation, Los Angeles, CA) database. Patients with a new or known diagnosis of a malignancy were included for this analysis. Longitudinal clinical histories were obtained from electronic medical records.RESULTS In total, 147794 abdominal CT scans were performed during the study period. Three hundred and fiftynine patients had mesenteric panniculitis(MP)-like abnormalities on their abdominal CT. Of these patients, 81 patients(22.6%) had a known history of cancer at the time of their CT scan. Nineteen(5.3%) had a new diagnosis of cancer in concurrence with their CT, but the majority of these(14/19, 74%) were undergoing CT as part of a malignancy evaluation. Lymphomas were the most common cancers associated with MPlike findings on CT(36 cases, 36%), with follicular lymphoma being the most frequent subtype(17/36). A variety of solid tumors, most commonly prostate(7) and renal cell cancers(6) also were seen. CT follow up was obtained in 56 patients. Findings in the mesentery were unchanged in 45(80%), worsened in 6(11%), and improved in 5 patients(9%). Positron emission tomography(PET) scans performed in 44 patients only showed a positive uptake in the mesenteric mass in 2 patients(5%). CONCLUSION A new diagnosis of cancer is uncommon in patients with CT findings suggestive of MP. MP-like mesenteric abnormalities on CT generally remain stable in patients with associated malignancies. PET scanning is not recommended in the evaluation of patients with mesenteric panniculitis-like findings on CT.
文摘Background: In 2010, the International Atomic Energy Agency launched the “3A’s campaign” as an effective tool for primary cancer prevention. In 2011, the American Association of Physicists in Medicine recommended the size specific dose estimate (SSDE). Objectives: To audit doses of Coronary CT Angiography (Coronary CTA) in tertiary care referral center. Methods: We reviewed 998 consecutive Coronary CTA (from 2007 to 2012). Doses (CTDIvol mGy), DLP (mGy*cm), effective dose (DLP*0.014, mSv) were on-line archived. SSDE was estimated retrospectively. Appropriateness score was evaluated for exams performed from the 2010. Results: Overall median dose per Coronary CTA was 49.7 mGy for CTDIvol, 55.5 mGy for SSDE, 994.96 mGy*cm for DLP, 13.9 mSv for effective dose. Median DLP decreased over time (1452.94 in 2007, 1605.56 in 2008, 1113.49 in 2009, 759.99 in 2010, 448.61 in 2011 and 497.88 mGy*cm in 2012, p < 0.0001). SSDE was proportional to the size dependent factor (SDF);in patients with SDF > 1 (88%) CTDIvol underestimated SSDE (48.49 vs 57.19 mGy), whilst in patients with SDF < 1 (12%) CTDIvol overestimated SSDE (56.46 vs 50.3 mGy). Scans were appropriate in 58%, uncertain in 24%, and inappropriate in 18% of cases. Doses were similar in appropriate, uncertain or inappropriate examinations and in excellent-to-good (81%) vs. sufficient-to-poor (19%) image quality exams. Conclusions: Coronary CTA reference doses can be very misleading. SSDE can allow individual technique optimization. The dose is similar in appropriate and inappropriate examinations, and unrelated to image quality. The rate of inappropriate examinations is still too high even after dissemination of guidelines.
基金supported by the National Key Research and Development Program of China (No. 2017YFC1309100)National Natural Scientific Foundation of China (No. 81771912, 81601469, and 81701782)+1 种基金the Science and Technology Planning Project of Guangdong Province (No. 2017B020227012)the Science and Technology Planning Project of Guangzhou (No. 20191A011002).
文摘Objective: To develop and validate a computed tomography(CT)-based radiomics nomogram for predicting human epidermal growth factor receptor 2(HER2) status in patients with gastric cancer.Methods: This retrospective study included 134 patients with gastric cancer(HER2-negative: n=87;HER2-positive: n=47) from April 2013 to March 2018, who were then randomly divided into training(n=94) and validation(n=40) cohorts. Radiomics features were obtained from the CT images showing gastric cancer. Least absolute shrinkage and selection operator(LASSO) regression analysis was utilized for building the radiomics signature. A multivariable logistic regression method was applied to develop a prediction model incorporating the radiomics signature and independent clinicopathologic risk predictors, which were then visualized as a radiomics nomogram. The predictive performance of the nomogram was assessed in the training and validation cohorts.Results: The radiomics signature was significantly associated with HER2 status in both training(P<0.001) and validation(P=0.023) cohorts. The prediction model that incorporated the radiomics signature and carcinoembryonic antigen(CEA) level demonstrated good discriminative performance for HER2 status prediction,with an area under the curve(AUC) of 0.799 [95% confidence interval(95% CI): 0.704-0.894] in the training cohort and 0.771(95% CI: 0.607-0.934) in the validation cohort. The calibration curve of the radiomics nomogram also showed good calibration. Decision curve analysis showed that the radiomics nomogram was useful.Conclusions: We built and validated a radiomics nomogram with good performance for HER2 status prediction in gastric cancer. This radiomics nomogram could serve as a non-invasive tool to predict HER2 status and guide clinical treatment.
文摘AIM To recognize the characteristic findings of non pathologic perfusion defects with CT arterial portography (CTAP) and nonpathologic enhancement found in CT hepatic arteriography (CTHA). METHODS The manifestations of nonpathologic perfusion defects with CTAP and non pathologic enhancement found in CTHA were analyzed in 50 patients with primary hepatocellular carcinoma. RESULTS The false positive rate of perfusion defects detected in CTAP was 15 1%. The shapes of perfusion defects were peripheral wedge, small, round, and patchy. The occurrence rate of non pathologic enhancement found in CTHA was 22 0%. The shapes of non pathologic enhancement were small, round, irregular, and wedge. CONCLUSION There was a high frequency of non pathologic perfusion defects detected with CTAP and non pathologic enhancement found in CTHA. The simultaneous use of both procedures may help decrease the false positive rate, and increase the veracity of diagnosis for hepatocellular carcinoma.
文摘CT guided percutaneous transthoracic fine needle aspiration biopsy (PTFNAB) was performed in twenty four sputum negative cases of small peripheral pulmonary lesions smaller than 2 cm in diameter, which are not easily diagnosed or accessible to fibrobron choscopes. After thin slide scanning and localization with Somatom DR H computed tomography, pulmonary nodules were biopsied with a 20 Gauge needle guided by a ruler specially designed. Biopsy materials were used for cyto and histopathologic examinations. The diagnosis accuracy of biopsy was evaluated by the result of postoperative pathology and/or follow up for 2 years. Sixteen pulmonary lesions were proved to be malignant and 8 were benign. The sensitivity was 75.0% (12/16), speciti vity 100% (8/8) and accuracy 83.3% (20/24) according to cytopathology and 87.5% (14/16), 100% (8/8), 91.7% (22/24) by histopathology, respectively. Two cases of early stage peripheral lung cancer were detected and proved by operation. CT guided PTFNAB is safe and quick for diagnosis with high accuracy for small peripheral pulmonary lesions which are usually negative in sputum examination and bronchoscopy. PTFNAB should be routinely used in the diagnosis of lung neoplasms.
文摘Microstructural change of YBaCuO film/YSZ substrate with and without proton irradiation has been studied by scanning electron microscope and X- ray diffraction techniques. Structural analysis has shown that conversion from tetragonal to orthorhombic phases, reduction of nonsuperconducting phase and preferential rearrangement of crystal grains are all favorable to the improvement of superconductivity in the YBaCuO film supported by YSZ substrate by proton beam bombardment.
文摘This paper summarizes the new developments in the study of barium rare-earth fluor-carbonate mineral structures .The second order superstructure of cebaite -(Ce ) was solved by using high power X-ray single crystal diffractometer . Five kinds of coordination forms were found . All atoms in the cell , including C and F , were properly located . In the process of study in a cordylite-(Ce ), a new mineral was discovered , whose chemical formula is (Ca0.5□0.5) BaCe2 (CO3)4F . It is isostructural with baiyuneboite - (Ce ), but different in composition (Na in baiyuneboite- (Ce ) is substituted by Ca disorderly ) . On the basis of the studies a proposal to re-define cordylite-(Ce )as a mineral group name is put forth by the authors . Finally a new type of twinning of huanghoite-(Ce ) was found on the systematical absence of diffraction data by means of a single crystal diffractometer .
文摘随着鼻窦CT诊断和鼻内镜诊疗技术的发展,大量鼻部疾病导致的头痛得以治愈。根据2004年国际头痛协会的分类,鼻源性头痛的第二种类型——黏膜接触点性头痛(mucosa contact point headache),因为缺少典型的鼻部症状,而分散就诊于其他学科,长期得不到合理诊疗。我们近期总结了多例临床上没有典型的鼻部症状,而是以各种类型的头痛为主诉就诊于神经内科等专科的患者,经过会诊筛查,确诊为鼻源性黏膜接触点性头痛,通过鼻内镜手术治愈。其中包括1组女性患者,长期被误认为是月经前期头痛,通过治疗证明是黏膜接触点性头痛的一种特殊存在形式,撰文总结如下。
文摘Objective:To investigate the rol e of CT scanning in diagnosing severe acute respiratory syndrome(SARS). Methods: One hundred and twelve times of spiral CT scanning, 106 t imes on the chest with standard pulmonary and mediastinal window, 5 on the brain and once on the abdomen, were performed in 82 patients (37 males and 45 females ) of SARS. Results: Bilateral shadows showed in 66 patients (80.48%) and unil ateral shadow in 16 (19.52%). The lung CT findings were sub pleural focal con solidation in 26 patients (31.70%), flaky cloudy opacity in 53 (64.63%), large a rea consolidation in 9 (10.97%), ground glass blurry shadow in 31 (37.80%), a lveolar substantive shadow in 14 (17.07%) and interstitial changes in 16 (19.51% ). The pulmonary CT signs of SARS were relatively characterized by: (1) The lesi ons tending to multiply occur, mostly to be bilaterally distributed and commonly involved in the lower lung field. (2) The lung shadows mostly showed as sub pleural focal consolidation, flaky cloudy shadow, large area consolidation, grou nd glass blurry shadow, and often accompanied with signs of broncho inflat ion. (3) Having opacified nodular shadows in the alveolar cavities. (4) Rapid pr ogressions or changes on the size, amount, and distribution of the lesions likel y to be found in dynamic observation of chest X ray and CT scanning, i.e., ma rkedly dynamic changes found within 24 to 48 hrs. Lesions with these characteris tics may be recognized as pulmonary changes possibly induced by SARS. Complicati ons were found in 6 patients (7.31%), including tuberculosis of lung and brain a ccompanied with pneumomediastinum in one patient, secondary infection of lung in 2, pneumothorax in 1, pulmonary fungus in 1, and pyothorax in 1.Conclusion: CT scanning is a sensitive method for diagnosis of SAR S, by which more accurate assessment of the abnormal changes of lung and occurre nce of complications in SARS patients can be made.
文摘Objective:To examine CT and pathologic presentations of the periphery of hepatocelllar carcinoma (HCC) by using in vivo liver specimens from orthotopic liver transplantation (OLT) and to see whether there is any correlation between them. Materials and Methods:Forty-two patients with HCC confirmed by pathology and liver transplantation were included. Plain CT scan covering the whole liver was done, followed by arterial and portal venous phase scanning. The delay time was 25 s and 60 s after injection of contrast medium. Fresh liver samples were evaluated, sliced and stained with HE and the standard immunoperoxidase method using facterⅧrelated antigen (F8RA) monoclonal antibody to study CT presentation of the periphery of tumor and compare them with pathologic findings. Results: (1) Tumors with clear boundaries on CT scan reflected the presence of tumor capsules in pathologic sections. Most tumors with unclear boundaries had no capsules and grew in an invasive pattern; (2) Tumors with unclear boundaries or high density on dynamic enhancement usually had abundant newborn vessels in the periphery and were poorly differentiated, while those with low density had few newborn vessels and were well differentiated; (3) When microvessel density (MVD) was>30, the occurrence of intrahepatic daughter foci was higher. Conclusion: (1) CT morphologic classification of the HCC periphery can well reflect the intactness of tumor capsules, which is helpful for preoperative assessment of tumor infiltration and cancer cell grading; (2) CT enhancement presentation of the HCC periphery in arterial and portal phases may reflect pathologic changes and help predict the prognosis at large.
文摘The launderability of wool fabrics treated by nano finoshing agent influences directly the functional endurance of he treated wool fabric. In order to investigate the effect of wool fibers surface modification on the functional erdurance of nano finishinp wool fibers, in this paper, for the first time wool fibers were chemically modified by using NaClO aqueous and KMnO4 aqueous, and then chemically modified wool fibers and native wool fibers were treated using nano ZnO finishing agent, respectively. The launderability of wool fibers treated by nano finishing agent was investigated. The experimental results show that the chemically modified wool fibers have a good launderaility after being treated by nano ZnO finishing agent treating. The surface morphologies of wool fibers were observed by using SEM. It is got that there is a strong adbesion between nano ZnO and wool surface through XPS analysis.
文摘Objectives To evaluate the ability of CT pleurography (CTP) in detecting minor pleural lesions in patients with pleural effusion and to assess its value in distinguishing malignant from benign pleural lesions. Methods A prospective study of 50 patients with pleural effusion was conducted using conventional CT and CTP. CT scan was run after injecting an appropriate amount of contrast medium into the pleural cavity. Results In 24 patients, all lesions detected by conventional CT were demonstrated by CTP. In 13 of 24 patients, CT pleurography detected additional lesions. In 20 of 26 patients with negative findings on conventional CT, CTP was capable of demonstrating the presence of pleural lesions. The sensitivity, specificity and accuracy of detecting pleural lesions were 25%, 100% and 30% for conventional CT, 86%, 100% and 87% for CTP, respectively. Conclusion CTP is superior to conventional CT in detecting and for the differential diagnosis benign and malignant pleural lesions.
文摘Objective To investigate the clinical and imaging characteristics of severe acute respiratory syndrome (SARS), and to study their relationship Methods Forty six SARS confirmed patients were admitted to our hospital from February to April, 2003 X ray examination documents were available in all cases and chest CT scanning was acquired in 6 cases, which were analyzed retrospectively, accompanied by their clinical features Results Fever was found in 97 8% of the patients Clinical symptoms were mild, but X ray and CT findings were distinct CT scanning demonstrated ground glass like lesions and large patchy exudation and consolidation at the early stage in 6 cases Different findings on radiography and CT were related to the different phases of the disease After treatment, most lesions were absorbed completely, but slowly in patients with multi lobe consolidation and/or extensive interstitial infiltration Conclusion Special clinical and imaging findings could be found in SARS cases The prognosis of SARS patients is related to the degree of lesions detected by radiography and CT