烤瓷用镍-铬合金金属氧化膜的研究

目的 分析国产Ｎｉ－Ｃｒ合金在烤瓷烧结条件下所生成的金属氧化膜的性能,探讨颈部灰线的成因。方法 应用Ｘ线衍射法与电子扫描法对国产Ｎｉ－Ｃｒ合金铸年经烤瓷烧结后,表现氧化膜的物相以及氧化膜与基体合金的成分进行分析;同时,应用俄歇电子能谱对经烤瓷烧结后与未经烤瓷烧结的铸件表现氧化膜的厚度、各元素变化趋势进行了分析研究。结果经烧结后的铸件表现氧化膜中主要有Ｃｒ２Ｏ３、ＮｉＣｒ２Ｏ４、ＳｉＯ２等氧化物及合     

Surface Roughness Analysis and Prediction with an Artificial Neural Network Model for Dry Milling of Co–Cr Biomedical Alloys

The aim of this paper is to conduct an experimental study in order to obtain a roughness (Ra) prediction model for dry end-milling (with an AlTiCrSiN PVD-coated tool) of the Co–28Cr–6Mo and Co–20Cr–15W–10Ni biomedical alloys, a model that can contribute to more quickly obtaining the desired surface quality and shortening the manufacturing process time. An experimental plan based on the central composite design method was adopted to determine the influence of the axial depth of cut, feed per tooth and cutting speed process parameters (input variables) on the Ra surface roughness (response variable) which was recorded after machining for both alloys. To develop the prediction models, statistical techniques were used first and three prediction equations were obtained for each alloy, the best results being achieved using response surface methodology. However, for obtaining a higher accuracy of prediction, ANN models were developed with the help of an application made in LabView for roughness (Ra) prediction. The primary results of this research consist of the Co–28Cr–6Mo and Co–20Cr–15W–10Ni prediction models and the developed application. The modeling results show that the ANN model can predict the surface roughness with high accuracy for the considered Co–Cr alloys.     

青少年症状性腓下骨合并痛风性踝关节炎的手术治疗

[目的]探讨青少年症状性腓下骨合并痛风性踝关节炎的手术疗效.[方法]回顾性分析2018年2月-2019年8月本科收治的症状性腓下骨合并痛风性踝关节炎15例患者的临床资料.男10例,女5例,左侧8例,右侧7例,年龄14～18岁,平均(15.73±1.03)岁.所有患者均采用踝关节镜下清理、腓下骨切除、Brostr(o)m...     

哈尼医药未成体系原因刍议

从历史、宗教、文字、传承、地域五个方面,分析了哈尼族医药未成体系之原因。     

Antihyperglycaemic activity of aqueous leaf extract of Combretum micranthum (Combretaceae) in normal and alloxan-induced diabetic rats

Aim of the study

To investigate antidiabetic effect of the leaves of Combretum micranthum G. Don, a medicinal plant used for treating diabetes in Northwestern Nigeria.

Materials and methods

Three doses (100 mg/kg, 200 mg/kg and 400 mg/kg) of the aqueous leaf extract of Combretum micranthum were administered to normal glucose loaded, subdiabetic and diabetic rats.

Results

Of the doses tested, 100 mg/kg of the extract was the most effective. It produces a significant hypoglycaemic and antidiabetic activity comparable to the effect of standard drug (0.6 mg/kg glibenclemide).

Conclusion

This study demonstrated the potential antidiabetic property of aqueous leaf extract of Combretum micranthum thus justifying its traditional usage.     

姜花酮的新颖氢化产物

以Raney Ni为催化剂,对姜花酮进行氢化反应,除得到正常全氢化产物外,还得到一个新颖产物,对其生成机理进行了讨论。     

La atropina superdiluida al 0,01% frena el aumento de miopía en niños-adolescentes. Un estudio a largo plazo 5 años de evolución: seguridad y eficacia

Objective

To confirm the clinical security and effectiveness of the daily application of 0.01% superdiluted atropine eyedrops in the progression of myopia in children.

Membrana neovascular asociada a drusas del nervio óptico en edad pediátrica: a propósito de un caso

Purpose

To describe the anatomical and functional results of intravitreal antiangiogenic treatment in optic nerve head drusen associated with choroidal neovascularisation.

Ecografía Doppler renal con medición de índices de resistencia vs. gammagrafía renal con 99mTc-DTPA para el diagnóstico de estenosis ureteropiélica en niños

ObjectiveA cross-sectional study was carried out with the objective of evaluating the usefulness of Doppler ultrasound with resistive index (RI) measure compared with renal scintigraphy with ^99mTc-DTPA in children with unilateral ureteropelvic junction obstruction.MethodsThe study included children under 15 years with a diagnosis of unilateral ureteropelvic junction obstruction, healthy contralateral kidney with or without an antecedent of ureteropyeloplasty. The selected patients were sent to the Nuclear Medicine Department to carry out a renal scintigraphy with ^99mTc-DTPA and days later were sent to the Radiology Department for the performance of Renal Doppler Ultrasound with RI.ResultsA total of 21 patients were included in the study, 15 males and 6 females, representing 71.4% and 28.6%, respectively. Mean age was 5.3 years. Only 3 had an antecedent of ureteropyeloplasty in the affected kidney. The scintigraphy reported data of unilateral obstruction in 18 patients, including the 3 patients with previous surgery. The average glomerular filtration rate (GFR) obtained with the scintigraphy was 100.28 ml/min. The average GFR in affected kidneys was 43.03 ml/min and 57.24 ml/min in healthy kidneys (p < .001). Doppler ultrasound with RI reported ectasia in 100% of the affected kidneys and one normal contralateral kidney. The average RI in affected kidneys was 0.69 mm/s and 0.50 mm/s in healthy kidneys (p < .001).ConclusionsWith the results obtained, we can suggest that ultrasound Doppler with measurement of RI can be an alternative tool to renal scintigraphy with ^99mTc-DTPA in some cases.     

The role of RANK/RANKL/osteoprotegerin (OPG) triad in cancer-induced bone diseases: physiopathology and clinical implications

Bone homeostasis is maintained by the remodelling of bone which depends on a balance between osteoclast-mediated bone resorption and osteoblast-mediated bone formation. Malignant bone lesions are very common in patients with cancer; whether they result from a tumor in bone (giant cell tumour of bone, osteosarcoma, multiple myeloma...) or they are bony metastases from advanced cancers of which the most osteotropic are breast and prostate cancer. Malignant cells within the bone disrupt the normal bone remodelling process, leading to increased bone destruction and occurence of pathological fractures. Receptor activator of NF-kB (RANK) and its ligand (RANKL) play a pivotal role in the regulation of bone remodelling; by binding to RANK, RANKL stimulates osteoclastogenesis and bone resorption, whereas its cognate decoy receptor osteoprotegerin (OPG) blocks this process by interacting with RANKL. Tumour cells produce different factors that manipulate the RANK/RANKL/OPG pathway in order to stimulate bone destruction. Furthermore, pending on the tumour type, RANKL plays a role in the migration, invasion and proliferation of malignant cells within the bone, while OPG increases survival of tumour cells. Inhibition of RANK/RANKL system may therefore offer new therapeutic perspectives for the treatment of primitive and secondary bone cancers.