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[en] Objective: To evaluate the effect of digital subtraction angiography and transcatheter embolization for gastrointestinal hemorrhage. Methods: Twenty patients with gastrointestinal hemorrhage received celiac arteries, superior mesenteric arteries and inferior mesenteric arteries angiography. Superselective angiography were performed when the arteries were suspicious by clinic or angiogrraphy. Ten patients with definite diagnosis and manifestation of hemorrhagic arteries by angiography were embolized after superselective catheterization with gelfoam particles, gelfoam particles and coils, polyvinyl alcohol particles. Results: The positive signs were observed in 13 cases. The DSA features including contrast medium accumulation in the gastrointestinal tract outside vascular, aneurysm, tumorous vascularization and staining, artery affect and local vasospasm. The bleedings were stopped immediately in 8 patients. No rebleeding and intestinal ischaemia or necrosis were observed in 30 days. One patient died in the second day after embolization from multiple organ failure. Rebleeding occurred 3 days after embolization in another patient, and was recovered after surgical operation. Conclusion: DSA is more effective for the diagnosis of gastrointestinal vascular malformation and tumors complicating acute bleeding. Transcatheter embolization is effective and safe to control the hemorrhage. (authors)
[en] Objective: To investigate the technic and the clinical effect of uterine arterial embolization as the treatment of uterine leiomyoma. Methods: Bilateral uterine arterial embolization was performed in 16 patients with uterine leiomyomas. The embolic agents were polyvinyl alcohol (PVA) particles sided 350 μm-500 μm in diameter and gelfoam. The clinical manifestations and the size of tumors were investigated in a 6-month post-procedure follow-up. Results: In all patients with hypermenorrhea was relieved, in average the uterine size was reduced by 48.9% and the size of tumor was reduced by 49.2% after the intervention. No serious complication occurred. Conclusion: Uterine arterial embolization is effective in relieving the clinical symptoms and debulking the leiomyoma. it is a valuable technique, and easily accepted by patients
[en] Objective: To observe the efficacy of interventional therapy on iatrogenic hemobilia. Methods: A retrospective study was conducted on 8 patients with iatrogenic hemobilia. The efficacy of interventional therapy along with causes, material and methods was analyzed. Results: after treatment was observed. Results During the hepatic artery angiography of 8 patients, 5 cases showed hepatic artery pseudoaneurysm, 2 cases showed turbulence of distal artery with contrast extravasate, 1 cases showed negative result. All patients accepted artery embolization successfully. Hemobilia stopped in 7 cases, and did not recur after 1 month. In the other one case hemobilia remained and the patient died after 1 week. Conclusion: Interventional therapy had significant effects on iatrogenic hemobilia, and it may be the first way for iatrogenic hemobilia. (authors)
[en] Objective: To evaluate the manifestation of arterial angiography and effect of intra-arterial embolization on the diagnosis and therapy of acute gastrointestinal tract bleeding. Methods: Selective arterial angiography of celiac trunk, superior mesenteric artery and inferior mesenteric artery was performed on 23 cases of acute gastrointestinal tract bleeding. Intra-arterial embolization was performed in 12 cases with positive findings. The embolizing materials were gelfoam particles, gelfoam with coils and polyvinyl alcohol particle. Results: 15 of 23 cases were presented with positive findings. The findings under angiography included contrast extravasation, aneurysm, neovascularization or tumorous stain, arterial invasion and local vascular spasm, etc. 12 of the positive cases underwent intra-arteial embolization. The bleeding was stopped in 10 cases without re-bleeding within 30 days, without intestinal ischemia or intestinal necrosis. One case died of multiple organ failure on the next day after embolization. Re-bleeding occurred in one case three days later and was cured after surgical intervention. Conclusion: The application of angiography and intra-arterial embolization is safe and effective in diagnosis and therapy for acute gastrointestinal tract bleeding. (authors)
[en] Objective: To evaluated the efficacy and safety of CT-guided percutaneous 125I seed implantation combined with bronchial arterial infusion chemotherapy for advanced lung cancers. Methods: A total of 108 patients with advanced lung cancer were enrolled in this study. The patients were randomly divided into study group (n = 43, 57 lesions) and control group (n = 65, 74 lesions). CT-guided percutaneous 125I seed implantation combined with bronchial arterial infusion chemotherapy of GP scheme (2∼4 cycles) was carried out in the patients of study group, while only bronchial arterial infusion chemotherapy of GP scheme (2∼4 cycles) was employed in the patients of control group. The clinical efficacy and the adverse effects were recorded, and the results were compared between the two groups. Results: The overall response rates at 1, 3, 6 and 12 months after the treatment in the study group were 8.8%, 56.1%, 63.6% and 84.0% respectively, and in the control group those were 2.7%, 21%, 41.9% and 45.1% respectively. The difference in the overall response rate between the two groups was statistically significant (P < 0.05). The one-year survival rates of the study group and the control group were 91% and 65%, respectively. The median survival time was 533 days in the study group and 422 days in the control group. The difference between the two groups was significant (P < 0.05). The main complications related to CT-guided percutaneous 125I seed implantation included pneumothorax, hemoptysis, seed migration and hemathorax. The main adverse effects due to chemotherapy were arrest of bone marrow and gastrointestinal toxic reactions which were tolerated by the patients. No significant difference in the occurrence of adverse effects existed between the two groups (P > 0.05). Conclusion: CT-guided percutaneous 125I seed implantation comhined with bronchial arterial infusion chemotherapy is a safe, effective and minimally-invasive treatment for advanced lung cancers. (authors)
[en] Lithium-sulfur (Li-S) batteries are one of the most promising next-generation batteries owing to their ultra-high theoretical energy density and that sulfur is an abundant resource. During the past 20 years, various sulfur materials have been reported. As a molecular-scale sulfur-composite cathode, sulfurized pyrolyzed poly(acrylonitrile) (S@pPAN) exhibits several competitive advantages in terms of its electrochemical behavior. Although it was first reported in 2002 S@pPAN is currently attracting increasing attention. In this Minireview, we summarize its molecular model and explore the correlation between its structure and its exceptional electrochemical performance. We classify the modification strategies into three types, including material improvement, binder, and electrolyte screening. Several research and development directions are also suggested. (© 2019 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
[en] Research highlights: → Sulfur addition increased the softening point and carbon yield of coal tar pitch. → The mechanical properties of the composites reached a maximum at 7 wt. % of sulfur. → The friction coefficient rose monotonously with increasing the content of sulfur. → The wear rate of the composites reached a minimum at 7 wt. % of sulfur. → The wear mechanism of composites was adhesive wear, abrasive wear and oxidative wear. - Abstract: Bronze-impregnated carbon-matrix composites were prepared through compression molding, carbonization and impregnation. The mechanism of sulfuration was studied, and the effect of coal tar pitch modified by sulfur as a binder on the mechanical and tribological properties of composites was investigated by varying the content of sulfur. The results showed that the sulfur addition increased the softening point, carbon yield and C/H atomic ratio of coal tar pitch but decreased the toluene solubility and quinoline solubility due to the dehydrogenating polymerization of pitch molecules. The micro-hardness, bending strength and compressive strength of the composites were enhanced by increasing the mass percentage of sulfur and reached a maximum of 160 HV, 132.82 MPa and 293 MPa at 7 wt. % of sulfur, respectively. However, both the hardness and strength of the composites decreased as the content of sulfur increased beyond 7 wt. %. The friction coefficient value of composites increased monotonously, but the wear rate decreased with increasing sulfur content; subsequently, the wear rate reached a minimum of 3.045 x 10-7 mm3/Nm at 7 wt. % of sulfur and then ascended. The wear mechanisms of the composites were adhesive wear, abrasive wear and oxidative wear. However, adhesive wear and oxidative wear occurred slightly for the composites with the binder modified by sulfur.
[en] Chromizing coating was fabricated on P110 oil casing tube steel by employ of pack cementation to improve the performance and increase the life-time during operation. Scanning electron microscope (SEM), X-ray diffraction (XRD), glow discharge optical emission spectroscope (GDOES) and microhardness tester were used to investigate the surface morphology, cross-sectional microstructure, phase constitutions, element distribution and microhardness distribution of the coating. Friction and wear behaviors of P110 steel and chromizing coating were measured using a ball-on-disc type tribometer under sliding against two counterparts in dry and wet conditions. The variations in friction coefficient, mass loss and surface morphologies of the tested samples were systemically investigated and analyzed. Energy dispersive spectrometer (EDS) and SEM were employed to elucidate the wear mechanisms of the tested samples. The results showed that the obtained coating was uniform and compact, mainly consisted of MxCy and reached a thickness of 55 μm. Chromizing coating had higher surface hardness and lower mass losses than that of P110 steel. When sliding against GCr15, chromizing coating showed no obvious friction-reduction effect, but indicated certain anti-friction property in sliding against Si3N4. The tested samples varied with surface hardness values and surface compositions have shown different wear mechanisms in the sliding tests. Chromizing treatment makes it possible to create on the working surface of P110 steel with enhanced surface hardness and wear resistance.
[en] Highlights: • Wear rate of nitrided HEAs was lower than that of as-cast HEAs in the same condition. • The wear mechanism of as-cast alloys in air was abrasive wear of oxide particles. • The wear mechanism of the nitrided HEAs in air was adhesive wear and abrasive wear. • The wear mechanism of HEAs in acid rain was abrasive, oxidative and corrosive wear. • The lubrication action of deionized water and acid rain led to the lower wear rate.