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目的 评估伊马替尼对慢性髓性白血病慢性期（CML-CP）儿童身高的影响。 方法 2018年7月至2019年7月，在全国范围内对诊断时年龄0.05）。多因素分析显示，服药初始年龄较小（偏回归系数为0.122，B＝0.572，t＝10.733，P

Radiation therapy is the first choice for the treatment of nasopharyngeal carcinoma. However, it is inevitable that nasopharyngeal mucosa and tissue will be damaged after radiotherapy of nasopharyngeal carcinoma, which will cause corresponding complications. Nasopharyngeal osteonecrosis is a serious complication. Up to now, there are few reports about nasopharyngeal osteonecrosis, and the underlaying pathological mechanism remains unclear. The potential theories include radiotherapy damage, infection and trauma, but also the " three H" principle of hypoxic hypocellular hypovascular tissue, as well as the theory of radio induced fibrosis. It is controversial about the treatment of nasopharyngeal osteonecrosis. It takes comprehensive treatment, including local treatment, systemic treatment, surgical treatment and other treatments. Among them, local treatment as nasopharyngeal debridement usually is first choice. We reviewed the pathological mechanism and treatment methods of nasopharyngeal osteonecrosis, in order to provide a reference for better prevention and treatment of it.

Transition curves play an important role in riding quality, especially for high-speed railways. Accordingly, various curves have been proposed as transition forms. To evaluate the effects of the forms in transition curves, the basic requirements and forms of transition curves were first discussed, and then simulations were performed with several typical transition curves at various speeds, based on the dynamic model developed in this research. The results indicate that the dynamic effects of transition curves are determined by the curvature variation and the order of the curvature derivative that is equal to zero at the curve endpoints, while the expression mode (such as algebraic or trigonometric expression) does not make much difference. From a dynamic viewpoint, the ideal transition form requires that the second derivative of its curvature is equal to zero at the curve endpoints at least, such as the seventh parabola, ninth parabola, and sinusoid, with which the vibration accelerations of the vehicle vary smoothly and the jerk can be effectively eased. Then the appropriate transition forms are recommended for ordinary and high-speed railways, respectively.

Laryngotracheal stenosis is a complex and dangerous disease,which caused by trauma or endotracheal intubation.Accurately and clearly to show the length and area of the airway stenosis,which is of great significance for the correct qualitative and quantitative diagnosis of the disease and the development of the treatment.The relevant inspection has its advantages and disadvantages.How to use inspection accurate and reasonable,there is no unified standard.Therefore,this paper will evaluate the role and significance of different relevant inspection(pulmonary function tests,ultrasound,bronchoscopy,CT,MRI) in the diagnosis of laryngotracheal stenosis,providing reference for laryngeal and tracheal stenosis diagnosis and treatment.

The effects of Sr and B addition on the microstructure and mechanical properties of AZ91 alloy were studied. The results of this work show that a small amount of Sr addition to AZ91 refined the grain size. The highest tensile strength was obtained from the alloy with the optimal composition of 0.5% Sr and 0.09% B added, in which the average grain size was 42 μm. The tensile strength and elongation of the AZ91–0.5%Sr–0.09%B alloy were 151 MPa and 1.62%, respectively. Some needle-shaped Al4Sr particles distributed mainly at grain boundaries have been observed in the alloys with Sr and B additions. The fluidity is improved significantly, and the solidification range decreased by adding Sr and B. The liquidus of AZ91 alloy decreased markedly with the addition of Sr and B, but the solidus hardly changed. Therefore, the solidification range can be decreased, which will improve the die-casting properties.

The status of the hand-arm vibration exposure and action for reducing vibration risk in China is outlined. The survey indicated that more than three million workers are exposed to hand-arm vibration. The vibration syndrome has been reported in sixteen provinces; over ten industries and twenty types of job. The measurement and assessment were conducted on twenty-four types of vibrating tools under normal working condition. The investigation of preventive measures is described, which includes the development of anti-vibration tools, improvement of technological processes, personal protection. A series of standards and regulations involving local vibration drawn up and published since 1980s is reviewed.