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Beijing, China

PetroChina Company Limited , is a Chinese oil and gas company and is the listed arm of state-owned China National Petroleum Corporation , headquartered in Dongcheng District, Beijing. It is China's biggest oil producer. Traded in Hong Kong and New York, the mainland enterprise announced its plans to issue stock in Shanghai in November 2007, and subsequently entered trading on the Shanghai index. Wikipedia.

Growing evidence supports that microRNAs (miRNAs) play crucial roles in cancer progression by directly downregulating multiple targets. However, the underlying mechanisms of miRNAs in oral squamous cell carcinoma (OSCC) are poorly understood. In the current study, we found that miR-194 expression was markedly downregulated in both clinical OSCC tissues and OSCC cell lines, compared with adjacent non-cancerous tissues and normal tongue epithelial cell TEC, respectively. Overexpression of miR-194 suppressed, whereas miR-194-in promoted OSCC cell proliferation. Furthermore, we demonstrated that miR-194 could reduce the phosphoinositide 3-kinase (PI3K)/AKT/FoxO3a signaling pathway by suppressing acylglycerol kinase (AGK) directly, resulting in decreasing cyclin D1 expression and increasing expression of p21 in OSCC. In sum, our data provide compelling evidence that miR-194 functions as a potential tumor suppressor by inhibiting the PI3K/AKT/FoxO3a signaling pathway and might sever as a potential therapeutic target for OSCC patients. © 2015 Elsevier Masson SAS.

Qin S.,Petrochina
Shiyou Kantan Yu Kaifa/Petroleum Exploration and Development | Year: 2012

Twenty-two gas and twenty-two water samples were collected from producing wells in the Triassic Xujiahe Formation, Leikoupo Formation and Jialingjiang Formation and the Permian Maokou Formation, in the Middle Sichuan, South Sichuan and Northwest Sichuan gas areas. The difference of carbon isotopes was compared between free gas and water-soluble gas. The component and carbon isotopic composition of the free gas showed normal characteristics of organic gas, while the alkane gas released from gas field water had more 13C component, indicating that gas field water plays an obvious role of fractionation in carbon isotope of natural gas. During the gas accumulation, if much gas is released from formation water and mixed into free gas, the carbon isotopic composition of free gases may become heavier. So, the carbon isotopic composition of water-soluble gases provides a new perspective for the study of gas origin and gas accumulation mechanism. Mixing of gases released from formation water may be the factor causing the carbon isotope anomalies for natural gases from the Kuqa Depression, Tarim Basin; Jiulongshan region and Weiyuan gas field, Sichuan Basin; and volcanic gas reservoirs of the Songliao Basin.

Zhao J.,Petrochina
Petroleum Exploration and Development | Year: 2011

Aimed at the development situation for horizontal wells in low permeability reservoirs in the Jilin Oilfield, evaluation standards are established for the geological parameters of horizontal well adaptability in low permeability reservoirs. According to different permeability grade, eight blocks of two kinds, suitable for the development with horizontal wells, were selected. Take M block, N block, and E block as examples of reservoir development with horizontal wells. Five aspects, including fine geological description, parameter optimization of reservoir engineering, optimization of production and injection program, horizontal well trajectory control, and energy supplement are researched on horizontal well reservoir engineering optimization design. Reservoir engineering design parameters adapting to geologic characteristics of the Jilin Oilfield are given and a series of horizontal well development techniques is formed. Different energy supplement programs in N block are researched by Eclipse numerical simulation software. The cumulative production of horizontal well reaches the peak when water injection in vertical well is in the toe of horizontal well. The horizontal well application result in M block shows that the cumulative production of horizontal well is 2.5 times that of vertical Well 130-6 of the same period. © 2011 Research Institute of Petroleum Exploration & Development, PetroChina.

Disclosed are an intelligent test system and method for a multi-segment fractured horizontal well. The intelligent test method for a multi-segment fractured horizontal well comprises: step A: placing a test tubular column into an underground horizontal section; step B: setting a pressure building packer and a hanging packer by means of pressurization after the test tubular column is placed into an underground designed position; step C: breaking a hydraulic release connector to separate the hydraulic release connector from a seal pipe; step D: pulling out a first oil pipe, and reserving the tubular column comprising the seal pipe and located on the downstream part of the seal pipe in a horizontal well; and step E: placing a production tubular column or a communications tubular column into a vertical section of the horizontal well.

The present disclosure provides an olefin polymerization catalyst and a combined catalyst containing the same. The catalyst comprises a reaction product of a magnesium dialkoxide, a titanium compound, an electron donor compound A and an electron donor compound B, wherein the electron donor compound A is a sulfonyl compound represented by general formula I, X is a disubstituted or unsubstituted group 14 element atom, a monosubstituted or unsubstituted group 15 element atom or group 16 element atom, and the substituent is a monocyclic, polycyclic or heteroatom-containing cyclic group or an aliphatic chain; R

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