The conventional nonstationary convolutional model assumes that the seismic signal is recorded at normal incidence. Raw shot gathers are far from this assumption because of the effects of offsets. Because of such prob...The conventional nonstationary convolutional model assumes that the seismic signal is recorded at normal incidence. Raw shot gathers are far from this assumption because of the effects of offsets. Because of such problems, we propose a novel prestack nonstationary deconvolution approach. We introduce the radial trace （RT） transform to the nonstationary deconvolution, we estimate the nonstationary deconvolution factor with hyperbolic smoothing based on variable-step sampling （VSS） in the RT domain, and we obtain the high-resolution prestack nonstationary deconvolution data. The RT transform maps the shot record from the offset and traveltime coordinates to those of apparent velocity and traveltime. The ray paths of the traces in the RT better satisfy the assumptions of the convolutional model. The proposed method combines the advantages of stationary deconvolution and inverse Q filtering, without prior information for Q. The nonstationary deconvolution in the RT domain is more suitable than that in the space-time （XT） domain for prestack data because it is the generalized extension of normal incidence. Tests with synthetic and real data demonstrate that the proposed method is more effective in compensating for large-offset and deep data.展开更多
“as”成语在英语学习中很常见,现就多年的学习积累并参照一些语法书和词典,归纳总结,以供参考。 1.as watchful as a hawk 象鹰一样地注视 The security men should be as watchful as a hawk against the activities of the guilts. ...“as”成语在英语学习中很常见,现就多年的学习积累并参照一些语法书和词典,归纳总结,以供参考。 1.as watchful as a hawk 象鹰一样地注视 The security men should be as watchful as a hawk against the activities of the guilts. 公安战士应该象鹰一样注视罪犯的行动。 2、be used as a door-mat 任人践踏(用作门前的脚垫) It’s intolerable to be used as a door-mat.被人践踏是不能容忍的。展开更多
AIM: To evaluate the reverse transcriptase-PCR assay and multiple sampling for detection of cytokeratin-positive cells in peripheral blood of colorectal carcinoma patients and to investigate the clinical significance ...AIM: To evaluate the reverse transcriptase-PCR assay and multiple sampling for detection of cytokeratin-positive cells in peripheral blood of colorectal carcinoma patients and to investigate the clinical significance of micrometastasis in peripheral blood.METHODS: The expression of CK20 mRNA by RT-PCR was investigated in bone marrow, portal vein and peripheral blood in 58 colorectal cancer patients and 12 controls without known cancer. The peripheral blood was sampled twice at intervals of 3 d before operation. All the patients were followed up for one year.RESULTS: There was no positive expression of CK20mRNA in 12 volunteers. The positive expression of CK20mRNA was 77.6% (45/58) in bone marrow, and that in portal vein was 74.1% (43/58) of colorectal carcinoma patients.The positive expression of CK20mRNA cells in peripheral blood rose from 44.8% (26/58) to 69.0% (40/58) (P＜0.01).The total positivity of CK20mRNA expression in peripheral blood was similar to the positivity of CK20mRNA in bone marrow and portal vein. The positive rates became higher in later clinical stages than in early stages. The CK20mRNA positive patients had a higher relapse rate within one year than the CK20mRNA negative patients.CONCLUSION: Multiple blood sampling can increase the detection of tumor cells in peripheral blood by RT-PCR for CK20mRNA in colorectal carcinoma patients and it is as sensitive and specific as that of bone marrow and portal vein. This technique may be reliable and convenient to diagnose micrometastasis of colorectal carcinoma and has an important significance in determining the prognosis of cancer patients.展开更多
[Objective] The study aimed to discuss the influences of edge effect on orthopteran community in east slope of Helan Mountain.[Method] Samples are collected by using sample zone method.The different species of orthopt...[Objective] The study aimed to discuss the influences of edge effect on orthopteran community in east slope of Helan Mountain.[Method] Samples are collected by using sample zone method.The different species of orthopterans in different habitats are recorded.[Result] The percentage of Oedipodidae,Catantopidae and Pamphgidae in total are 42.65%,29.15% and 12.76% respectively.From scattered grassland interior to edge and then to desert grassland,abundance increase in turn,but diversity in the edge is the highe...展开更多
This paper analyses the diversity and spatial pattern of the altitudinal belts in the Hengduan Mountains in China. A total of 7 types of base belts and 26 types of altitudinal belts are identified in the study region....This paper analyses the diversity and spatial pattern of the altitudinal belts in the Hengduan Mountains in China. A total of 7 types of base belts and 26 types of altitudinal belts are identified in the study region. The main altitudinal belt lines, such as forest line, the upper limit of dark coniferous forest and snow line, have similar latitudinal and longitudinal spatial patterns, namely, arched quadratic curve model with latitudes and concave quadratic curve model along longitudinal direction. These patterns can be together ealled as ＂Hyperbolic-paraboloid model＂, revealing the complexity and speciality of the environment and ecology in the study region. This result further validates the hypnosis of a common quadratic model for spatial pattern of mountain altitudinal belts proposed by the authors. The spatial pattern of altitudinal belts is closely related with moisture-related exposure effect in the Hengduan Mountains. Different combinations （spectra） of altitudinal belts and different base belt types appear in windward and leeward flanks and even in the same flanks of different ranges. This is closely related with the parallel mountain ranges of the Hengduan Mountains, which, at nearly right angle with the moving direction of prevailing moisture-laden air masses from west and east, hold up the warm and humid monsoon wind from moving into the core region and result in different moisture conditions in windward and leeward flanks. However, how to quantitatively describe the moisture-related exposure effect needs further study. In addition, the data quality and data accuracy at present also affect to some extent the result of quantitative modeling and should be improved with RS/GIS in the future.展开更多
Sarcomatoid carcinomas of the colorectum are rare tu- mors that display both malignant epithelial and stromal components. Clinically, they are aggressive tumors with early metastasis. Due to their infrequent occurrenc...Sarcomatoid carcinomas of the colorectum are rare tu- mors that display both malignant epithelial and stromal components. Clinically, they are aggressive tumors with early metastasis. Due to their infrequent occurrence, the pathogenesis is poorly understood. We report a case of a 52-year-old woman who presented with a rectal mass and intermittent hematochezia. Superficial biopsies during colonoscopy revealed a tubulovillous adenoma with high-grade dysplasia. Endoscopic ultra- sonography confirmed an invasive nature of the mass, and deeper biopsies revealed the presence of neoplasm with mixed histological components. The surgically- excised specimen demonstrated the presence of poorly differentiated spindle cells underneath the tubulovillous adenoma and an intermediate stage of invasive adeno- carcinoma. Based on the histological appearance and immunohistochemical studies, a diagnosis of sarcoma- toid carcinoma was made. Only nine cases of sarcoma- toid carcinomas of the colorectum have been reported to date. As a result, the terminology and pathogenesis of sarcomatoid carcinoma remain speculative. To the best of our knowledge, this is the first report of co- existence of sarcomatoid carcinoma and invasive ad- enocarcinoma with tubulovillous adenoma; all stages represented within the same tumor. This observation supports the "monoclonal theory" of pathogenesis with an adenoma-sarcoma progression with or without an intermediate stage of carcinoma.展开更多
Objective： To evaluate the association between p53 codon 72 polymorphism （R72P） and the risk ofcolorectal liver metastases. Methods： The p53 R72P genotype was identified by polymerase chain reaction-restriction fr...Objective： To evaluate the association between p53 codon 72 polymorphism （R72P） and the risk ofcolorectal liver metastases. Methods： The p53 R72P genotype was identified by polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） method in 78 consecutive colorectal cancer patients with liver metastases and 214 age- and sex-matched cases with nonmetastatic colorectal cancer. Results： The R allele of the p53 R72P polymorphism was more frequently found in metastatic cases than in nonmetastatic cases （P=0.075）. Carriers of the 72R allele had a 2.25-fold （95% CI （confidence interval）=1.05-4.83） increased risk of liver metastases. On the stratification analysis, 72R-carrying genotype conferred a 3.46-fold （95% CI=1.02-11.72） and a 1.05-fold （95% CI=0.36-3.08） increased risk of liver metastases for p53 overexpression-positive and negative colorectal cancers, respectively. Conclusion： These results demonstrate for the first time that the 72R allele of the p53 polymorphism has an increased risk for liver metastases in colorectal cancers positive for p53 overexpression.展开更多
基金financially supported by the National Science and Technology Major Project of China(No.2011ZX05023-005-005)the National Natural Science Foundation of China(No.41274137)
文摘The conventional nonstationary convolutional model assumes that the seismic signal is recorded at normal incidence. Raw shot gathers are far from this assumption because of the effects of offsets. Because of such problems, we propose a novel prestack nonstationary deconvolution approach. We introduce the radial trace （RT） transform to the nonstationary deconvolution, we estimate the nonstationary deconvolution factor with hyperbolic smoothing based on variable-step sampling （VSS） in the RT domain, and we obtain the high-resolution prestack nonstationary deconvolution data. The RT transform maps the shot record from the offset and traveltime coordinates to those of apparent velocity and traveltime. The ray paths of the traces in the RT better satisfy the assumptions of the convolutional model. The proposed method combines the advantages of stationary deconvolution and inverse Q filtering, without prior information for Q. The nonstationary deconvolution in the RT domain is more suitable than that in the space-time （XT） domain for prestack data because it is the generalized extension of normal incidence. Tests with synthetic and real data demonstrate that the proposed method is more effective in compensating for large-offset and deep data.
文摘“as”成语在英语学习中很常见,现就多年的学习积累并参照一些语法书和词典,归纳总结,以供参考。 1.as watchful as a hawk 象鹰一样地注视 The security men should be as watchful as a hawk against the activities of the guilts. 公安战士应该象鹰一样注视罪犯的行动。 2、be used as a door-mat 任人践踏(用作门前的脚垫) It’s intolerable to be used as a door-mat.被人践踏是不能容忍的。
基金Supported by Natural Science Foundation of Jiangsu Province, No. 470DB9807
文摘AIM: To evaluate the reverse transcriptase-PCR assay and multiple sampling for detection of cytokeratin-positive cells in peripheral blood of colorectal carcinoma patients and to investigate the clinical significance of micrometastasis in peripheral blood.METHODS: The expression of CK20 mRNA by RT-PCR was investigated in bone marrow, portal vein and peripheral blood in 58 colorectal cancer patients and 12 controls without known cancer. The peripheral blood was sampled twice at intervals of 3 d before operation. All the patients were followed up for one year.RESULTS: There was no positive expression of CK20mRNA in 12 volunteers. The positive expression of CK20mRNA was 77.6% (45/58) in bone marrow, and that in portal vein was 74.1% (43/58) of colorectal carcinoma patients.The positive expression of CK20mRNA cells in peripheral blood rose from 44.8% (26/58) to 69.0% (40/58) (P＜0.01).The total positivity of CK20mRNA expression in peripheral blood was similar to the positivity of CK20mRNA in bone marrow and portal vein. The positive rates became higher in later clinical stages than in early stages. The CK20mRNA positive patients had a higher relapse rate within one year than the CK20mRNA negative patients.CONCLUSION: Multiple blood sampling can increase the detection of tumor cells in peripheral blood by RT-PCR for CK20mRNA in colorectal carcinoma patients and it is as sensitive and specific as that of bone marrow and portal vein. This technique may be reliable and convenient to diagnose micrometastasis of colorectal carcinoma and has an important significance in determining the prognosis of cancer patients.
基金Supported by Ministry of Education,New Century Excellent Talents Scheme(NCET-07-0470)~~
文摘[Objective] The study aimed to discuss the influences of edge effect on orthopteran community in east slope of Helan Mountain.[Method] Samples are collected by using sample zone method.The different species of orthopterans in different habitats are recorded.[Result] The percentage of Oedipodidae,Catantopidae and Pamphgidae in total are 42.65%,29.15% and 12.76% respectively.From scattered grassland interior to edge and then to desert grassland,abundance increase in turn,but diversity in the edge is the highe...
基金supported by the National Natural Science foundation of China (40971064)the Innovatioin Program of Chinese Academy of Sciences (No. kzcx2-yw-308)IGSNRR Youth Innovation Project,and the LREIS Self-determined Project
文摘This paper analyses the diversity and spatial pattern of the altitudinal belts in the Hengduan Mountains in China. A total of 7 types of base belts and 26 types of altitudinal belts are identified in the study region. The main altitudinal belt lines, such as forest line, the upper limit of dark coniferous forest and snow line, have similar latitudinal and longitudinal spatial patterns, namely, arched quadratic curve model with latitudes and concave quadratic curve model along longitudinal direction. These patterns can be together ealled as ＂Hyperbolic-paraboloid model＂, revealing the complexity and speciality of the environment and ecology in the study region. This result further validates the hypnosis of a common quadratic model for spatial pattern of mountain altitudinal belts proposed by the authors. The spatial pattern of altitudinal belts is closely related with moisture-related exposure effect in the Hengduan Mountains. Different combinations （spectra） of altitudinal belts and different base belt types appear in windward and leeward flanks and even in the same flanks of different ranges. This is closely related with the parallel mountain ranges of the Hengduan Mountains, which, at nearly right angle with the moving direction of prevailing moisture-laden air masses from west and east, hold up the warm and humid monsoon wind from moving into the core region and result in different moisture conditions in windward and leeward flanks. However, how to quantitatively describe the moisture-related exposure effect needs further study. In addition, the data quality and data accuracy at present also affect to some extent the result of quantitative modeling and should be improved with RS/GIS in the future.
文摘Sarcomatoid carcinomas of the colorectum are rare tu- mors that display both malignant epithelial and stromal components. Clinically, they are aggressive tumors with early metastasis. Due to their infrequent occurrence, the pathogenesis is poorly understood. We report a case of a 52-year-old woman who presented with a rectal mass and intermittent hematochezia. Superficial biopsies during colonoscopy revealed a tubulovillous adenoma with high-grade dysplasia. Endoscopic ultra- sonography confirmed an invasive nature of the mass, and deeper biopsies revealed the presence of neoplasm with mixed histological components. The surgically- excised specimen demonstrated the presence of poorly differentiated spindle cells underneath the tubulovillous adenoma and an intermediate stage of invasive adeno- carcinoma. Based on the histological appearance and immunohistochemical studies, a diagnosis of sarcoma- toid carcinoma was made. Only nine cases of sarcoma- toid carcinomas of the colorectum have been reported to date. As a result, the terminology and pathogenesis of sarcomatoid carcinoma remain speculative. To the best of our knowledge, this is the first report of co- existence of sarcomatoid carcinoma and invasive ad- enocarcinoma with tubulovillous adenoma; all stages represented within the same tumor. This observation supports the "monoclonal theory" of pathogenesis with an adenoma-sarcoma progression with or without an intermediate stage of carcinoma.
基金Project supported by the National Natural Science Foundation of China (No. 30470791) the Medical Science and Technology Research Foundation for the 11th Five-Year Program of People's Liberation Army, Nanjing Branch, China (No. 06MA27)
文摘Objective： To evaluate the association between p53 codon 72 polymorphism （R72P） and the risk ofcolorectal liver metastases. Methods： The p53 R72P genotype was identified by polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） method in 78 consecutive colorectal cancer patients with liver metastases and 214 age- and sex-matched cases with nonmetastatic colorectal cancer. Results： The R allele of the p53 R72P polymorphism was more frequently found in metastatic cases than in nonmetastatic cases （P=0.075）. Carriers of the 72R allele had a 2.25-fold （95% CI （confidence interval）=1.05-4.83） increased risk of liver metastases. On the stratification analysis, 72R-carrying genotype conferred a 3.46-fold （95% CI=1.02-11.72） and a 1.05-fold （95% CI=0.36-3.08） increased risk of liver metastases for p53 overexpression-positive and negative colorectal cancers, respectively. Conclusion： These results demonstrate for the first time that the 72R allele of the p53 polymorphism has an increased risk for liver metastases in colorectal cancers positive for p53 overexpression.
