Noninvasive or minimally invasive interventional surgery was selected, and the complications were less and had no significant impact on the quality of life of patients. Tumour patients are often accompanied by cerebrovascular diseases, metabolic diseases, and other basic diseases, which more or less adversely affect the surgical efficacy of tumour. In this paper, endovascular remobilization was used to treat tumour; the basic condition of patients before operation and the interventional operation plan were introduced. Through the analysis of clinical data and prognosis evaluation results of tumour patients receiving intravascular interventional therapy, the patients were divided into good prognosis group and poor prognosis group according to the modified Rankin scale score at discharge. The relationship between gender, age, history of hypertension, tumour width, tumour size, preoperative Hunt-Hess grade, interventional surgery method, and prognosis related to intravascular interventional therapy was explored. The results showed that intravascular interventional therapy for tumour patients can obtain a good prognosis, which provides a reference for the future preoperative assessment of treatment risk and possible prognosis and provides a theoretical basis for the formulation of treatment plan to improve prognosis.

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As the metallic stator progressing cavity pump (PCP) operates with the stator and rotor in clearance fit, the slippage between cavities has a significant influence on the pump performance. In this paper, an analytical model is developed for the flow in the metallic stator PCP. Based on the analyses of the meshing movement and the clearance geometry inside the pump, the slippage through the transversal and longitudinal sealing regions is calculated considering different slippage mechanisms. Then the flow rate is obtained by subtracting the total slippage from the theoretical volumetric rate. This model is validated against results obtained from the performance experiments of commercial metallic stator PCP products from Shihong Petroleum Equipment Company. The model results show that the metallic stator PCP with smaller clearance or more stages is more capable of achieving good performance at high differential pressure. It is suitable for pumping the fluid with certain viscosity, and the influence of the slippage can be compensated by adopting appropriate high rotational speed. Furthermore, the model can be used to predict the pump performance and provide guidance for the pump design and performance optimization in field applications.

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The crystal structures of aqua (2,2'-bipyrimidine-

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