AIM： To investigate the clinicopathological features of gastrointestinal stromal tumor （GIST） and to study the reference indexes for malignancy. METHODS： Fifty-two cases of primary GIST were distinguished from a g...AIM： To investigate the clinicopathological features of gastrointestinal stromal tumor （GIST） and to study the reference indexes for malignancy. METHODS： Fifty-two cases of primary GIST were distinguished from a group of gastrointestinal mesenchymal tumors using a panel of antibodies such as CD117 and CD34 by immunohistochemical SP method. Their biological behaviors were analyzed using the expression of p21WAF1 and Bax in 52 cases of GIST. RESULTS： Grossly, the tumor size was between 1.5 cm and 13 cm （mean： 5.5 cm）. Focal areas of hemorrhage, necrosis, or small cyst formation could be seen. Microscopically, the tumor was composed of spindle cells （20 cases）, epithelioid cells （20 cases） and mixed cells （12 cases）. Immunohistochemically, CDl17 and CD34 showed diffuse strong positive expressions, the positive rates were 98.1% and 92.3%. SMA, S-100, NSE, NF and MBP showed focal positive expressions, the positive rates were 48.1%, 28.8%, 25%, 21.2% and 42.3% respectively. Vimentins were all positive desmin and CgA were all negative. In normal adult stomach and intestine, the immunoreactive staining for CD117 and CD34 showed immunoreactive interstitial cells of Cajal in myenteric neuroplexus. Among the 52 cases of GIST, 27 were positive for p21WAF1 （51.9%）, 29 for Bax （55.8%）. The expression of p21WAF1 and Bax had no significent difference with the localization, size, histological subtype of GIST, but had a significent difference with the histological grade （P = 0.000, respectively）, p21WAF1 expression had a positive correlation to Bax expression （r = 0.461, P = 0.001, k = 0.459）. CONCLUSION： GIST has complicated arrangements and various cell types. Positivity of CD117 and CD34 is the most valuable factor in diagnosing GIST. Expression of p21WAF1 and Bax plays an important role in potential malignancy and malignancy rather than in benign GIST. p21WAF1 and Bax may be used as the markers in the assessment of GIST malignant potential.展开更多
Diffusion is an important mass transfer mode of tight sandstone gas. Since nano-pores are extensively developed in the interior of tight sandstone, a considerable body of research indicates that the type of diffusion ...Diffusion is an important mass transfer mode of tight sandstone gas. Since nano-pores are extensively developed in the interior of tight sandstone, a considerable body of research indicates that the type of diffusion is mainly molecular diffusion based on Fick＇s law. However, accurate modeling and understanding the physics of gas transport phenomena in nanoporous media is still a challenge for researchers and traditional investigation（analytical and experimental methods） have many limitations in studying the generic behavior. In this paper, we used Nano-CT to observe the pore structures of samples of the tight sandstone of western of Sichuan. Combined with advanced image processing technology, threedimensional distributions of the nanometer-sized pores were reconstructed and a tight sandstone digital core model was built, as well the pore structure parameters were analyzed quantitatively. Based on the digital core model, the diffusion process of methane molecules from a higher concentration area to a lower concentration area was simulated by a finite volume method. Finally, the reservoir＇s concentration evolution was visualized and the intrinsic molecular diffusivity tensor which reflects the diffusion capabilities of this rock was calculated. Through comparisons, we found that our calculated result was in good agreement with other empirical results. This study provides a new research method for tight sandstone digital rock physics. It is a foundation for future tight sandstone gas percolation theory and numerical simulation research.展开更多
文摘AIM： To investigate the clinicopathological features of gastrointestinal stromal tumor （GIST） and to study the reference indexes for malignancy. METHODS： Fifty-two cases of primary GIST were distinguished from a group of gastrointestinal mesenchymal tumors using a panel of antibodies such as CD117 and CD34 by immunohistochemical SP method. Their biological behaviors were analyzed using the expression of p21WAF1 and Bax in 52 cases of GIST. RESULTS： Grossly, the tumor size was between 1.5 cm and 13 cm （mean： 5.5 cm）. Focal areas of hemorrhage, necrosis, or small cyst formation could be seen. Microscopically, the tumor was composed of spindle cells （20 cases）, epithelioid cells （20 cases） and mixed cells （12 cases）. Immunohistochemically, CDl17 and CD34 showed diffuse strong positive expressions, the positive rates were 98.1% and 92.3%. SMA, S-100, NSE, NF and MBP showed focal positive expressions, the positive rates were 48.1%, 28.8%, 25%, 21.2% and 42.3% respectively. Vimentins were all positive desmin and CgA were all negative. In normal adult stomach and intestine, the immunoreactive staining for CD117 and CD34 showed immunoreactive interstitial cells of Cajal in myenteric neuroplexus. Among the 52 cases of GIST, 27 were positive for p21WAF1 （51.9%）, 29 for Bax （55.8%）. The expression of p21WAF1 and Bax had no significent difference with the localization, size, histological subtype of GIST, but had a significent difference with the histological grade （P = 0.000, respectively）, p21WAF1 expression had a positive correlation to Bax expression （r = 0.461, P = 0.001, k = 0.459）. CONCLUSION： GIST has complicated arrangements and various cell types. Positivity of CD117 and CD34 is the most valuable factor in diagnosing GIST. Expression of p21WAF1 and Bax plays an important role in potential malignancy and malignancy rather than in benign GIST. p21WAF1 and Bax may be used as the markers in the assessment of GIST malignant potential.
基金supported by Open Fund (PLN1506) of State Key Laboratory of Oil and Gas Reservoir Geology and ExploitationChinese National Natural Science Foundation (41502287)+2 种基金Chongqing Basic and Frontier Research Projects (CSTC2015JCYJBX0120)Chongqing City Social Undertakings and Livelihood Protection Science and Technology Innovation Special Project (CSTC2017SHMSA120001)Chongqing Land Bureau Science and Technology Planning Project (CQGT-KJ-2017026,CQGTKJ-2015044,CQGT-KJ-2015018, CQGT-KJ-2014040)
文摘Diffusion is an important mass transfer mode of tight sandstone gas. Since nano-pores are extensively developed in the interior of tight sandstone, a considerable body of research indicates that the type of diffusion is mainly molecular diffusion based on Fick＇s law. However, accurate modeling and understanding the physics of gas transport phenomena in nanoporous media is still a challenge for researchers and traditional investigation（analytical and experimental methods） have many limitations in studying the generic behavior. In this paper, we used Nano-CT to observe the pore structures of samples of the tight sandstone of western of Sichuan. Combined with advanced image processing technology, threedimensional distributions of the nanometer-sized pores were reconstructed and a tight sandstone digital core model was built, as well the pore structure parameters were analyzed quantitatively. Based on the digital core model, the diffusion process of methane molecules from a higher concentration area to a lower concentration area was simulated by a finite volume method. Finally, the reservoir＇s concentration evolution was visualized and the intrinsic molecular diffusivity tensor which reflects the diffusion capabilities of this rock was calculated. Through comparisons, we found that our calculated result was in good agreement with other empirical results. This study provides a new research method for tight sandstone digital rock physics. It is a foundation for future tight sandstone gas percolation theory and numerical simulation research.
