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991.
In Y-stenting, stabilization of the first stent may be problematic as in some cases it migrates during second stent insertion. This report evaluates the safety and effectiveness of the technique and presents the long-term results of hybrid, Y-configured, dual stent-assisted coil embolization in the treatment of wide-necked bifurcation aneurysms.We retrospectively evaluated the patients treated endovascularly due to cerebral aneurysms. Twenty patients treated with hybrid Y-stent-assisted coil embolization were enrolled in the study. In hybrid stenting, an open-cell intracranial stent (Neuroform) was used as a first stent to prevent stent migration. A closed-cell stent (Enterprise or Acclino) was used as a second stent and the aneurysm was embolized with coils between the stent struts.In all patients, hybrid Y-stenting and coil embolization were accomplished successfully. No stent migration occurred. Clinically, neither symptomatic neurologic complication nor death was seen. Of 20 wide-necked bifurcation aneurysms, nine were at the basilar tip, while seven were at the middle cerebral artery and three at the anterior communicating artery. In one patient, the aneurysm was at the A2-3 junction of the anterior cerebral artery. One of the patients had a subarachnoid hemorrhage. The mean angiographic follow-up was 25.6 months. No in-stent stenosis was seen in any of the patients and recanalization in only one.Hybrid, Y-configured, dual stent-assisted coil embolization is a safe and effective method in the treatment of wide-necked bifurcation aneurysms to prevent stent migration and aneurysm recanalization, and is a viable alternative to microsurgery. 相似文献
992.
993.
994.
In this study, the high strain rate deformation behavior and the microstructure evolution of Zr-Cu-Al-Ni metallic glasses under various strain rates were investigated. The influence of strain and strain rate on the mechanical properties and fracture behavior, as well as microstructural properties was also investigated. Before mechanical testing, the structure and thermal stability of the Zr-Cu-Al-Ni metallic glasses were studied with X-ray diffraction (XRD) and differential scanning calorimeter. The mechanical property experiments and microstructural observations of Zr-Cu-Al-Ni metallic glasses under different strain rates ranging from 10−3 to 5.1 × 103 s−1 and at temperatures of 25 °C were investigated using compressive split-Hopkinson bar (SHPB) and an MTS tester. An in situ transmission electron microscope (TEM) nanoindenter was used to carry out compression tests and investigate the deformation behavior arising at nanopillars of the Zr-based metallic glass. The formation and interaction of shear band during the plastic deformation were investigated. Moreover, it was clearly apparent that the mechanical strength and ductility could be enhanced by impeding the penetration of shear bands with reinforced particles. 相似文献
995.
Alexander Lisov Veronika Vrublevskaya Zoy Lisova Alexey Leontievsky Oleg Morenkov 《Viruses》2015,7(10):5343-5360
Various natural and synthetic polyanionic polymers with different chemical structures are known to exhibit potent antiviral activity in vitro toward a variety of enveloped viruses and may be considered as promising therapeutic agents. A water-soluble conjugate of 2,5-dihydroxybezoic acid (2,5-DHBA) with gelatin was synthesized by laccase-catalyzed oxidation of 2,5-DHBA in the presence of gelatin, and its antiviral activity against pseudorabies virus (PRV) and bovine herpesvirus type 1 (BoHV-1), two members of the Alphaherpesvirinae subfamily, was studied. The conjugate produced no direct cytotoxic effect on cells, and did not inhibit cell growth at concentrations up to 1000 µg/mL. It exhibited potent antiviral activity against PRV (IC50, 1.5–15 µg/mL for different virus strains) and BoHV-1 (IC50, 0.5–0.7 µg/mL). When present during virus adsorption, the conjugate strongly inhibited the attachment of PRV and BoHV-1 to cells. The 2,5-DHBA–gelatin conjugate had no direct virucidal effect on the viruses and did not influence their penetration into cells, cell-to-cell spread, production of infectious virus particles in cells, and expression of PRV glycoproteins E and B. The results indicated that the 2,5-DHBA–gelatin conjugate strongly inhibits the adsorption of alphaherpesviruses to cells and can be a promising synthetic polymer for the development of antiviral formulations against alphaherpesvirus infections. 相似文献
996.
研究表明2型糖尿病可能增加肺癌发生的风险,但其尚缺乏有力的相关机制研究。本文从2型糖尿病和肺癌间的流行病学特点、2型糖尿病患者的肺癌发病率升高、高血糖、胰岛素抵抗、高胰岛素血症、胰岛素样生长因子、血管内皮生长因子、炎症细胞因子、激素调节功能紊乱、免疫系统功能降低、微量元素及降糖药物等方面综述二者可能的相关性,但2型糖尿病加重肺癌的机制仍需要大量研究证明。 相似文献
997.
998.
William C Davis 《World journal of gastroenterology : WJG》2015,21(48):13411-13417
The historic suggestion that Mycobacterium avium subsp. paratuberculosis (Map) might be a zoonotic pathogen was based on the apparent similarity of lesions in the intestine of patients with Crohn’s disease (CD) with those present in cattle infected with Map, the etiological agent of Johne’s disease. Reluctance to fully explore this possibility has been attributed to the difficulty in demonstrating the presence of Map in tissues from patients with CD. Advances in technology have resolved this problem and revealed the presence of Map in a significant proportion of patients with CD and other diseases. The seminal finding from recent investigations, however, is the detection of Map in healthy individuals with no clinical signs of disease. The latter observation indicates all humans are susceptible to infection with Map and lends support to the thesis that Map is zoonotic, with a latent stage of infection similar to tuberculosis, where infection leads to the development of an immune response that controls but does not eliminate the pathogen. This clarifies one of the reasons why it has been so difficult to document that Map is zoonotic and associated with the pathogenesis of CD and other diseases. As discussed in the present review, a better understanding of the immune response to Map is needed to determine how infection is usually kept under immune control during the latent stage of infection and elucidate the triggering events that lead to disease progression in the natural host and pathogenesis of CD and immune related diseases in humans. 相似文献
999.
Thiago H Freitas Elias Andreoulakis Gilberto S Alves Hesley LL Miranda Lúcia LBC Braga Thomas Hyphantis André F Carvalho 《World journal of gastroenterology : WJG》2015,21(21):6713-6727
AIM: To investigate the relationship between sense of coherence, psychological distress and health related quality of life in inflammatory bowel disease (IBD).METHODS: This cross-sectional study enrolled a consecutive sample of 147 IBD (aged 45.1 ± 14.1 years; 57.1% female) patients recruited from a tertiary gastroenterology service. Sixty-four participants met diagnostic criteria for Crohn’s disease, while eighty-three patients had ulcerative colitis. Socio-demographic data (education, age, race, gender, gross monthly income and marital status), disease-related variables (illness activity, relapse rate in past 2 years, history of surgery and time since diagnosis), sense of coherence (Antonovsky’s SOC scale), psychological distress symptoms (Hospital Anxiety and Depression Scale) and health-related quality of life (HRQoL; WHOQOL-Bref) were assessed. Hierarchical multiple regression analyses were performed to identify factors that are independently associated with psychological distress and HRQoL in patients with IBD and to provide indications for possible moderating or mediating effects. In addition, formal moderation and mediation analyses (Sobel tests) were performed to confirm potential moderators/mediators of the relationship between SOC, psychological distress symptoms and HRQoL.RESULTS: Lower SOC scores (std beta= -0.504; P < 0.001), female gender (std beta = 0.176; P = 0.021) and White race (std beta = 0.164; P = 0.033) were independently associated with higher levels of depressive symptoms, while lower levels of SOC (std beta = -0.438; P < 0.001) and higher relapse rate (std beta = 0.161; P = 0.033) were independently associated with more severe anxiety symptoms. A significant interaction between time since diagnosis and SOC was found with regard to the severity of depressive or anxiety symptoms, as the interaction term (time since diagnosis X SOC) had beta coefficients of -0.191 (P = 0.009) and -0.172 (P = 0.026), respectively. Lower levels of anxiety symptoms (std beta = -0.369; P < 0.001), higher levels of SOC (std beta = 0.231; P = 0.016) and non-White race (std beta = -0.229; P = 0.006), i.e., mixed-race, which represented the reference category, were independently associated with higher levels of overall HRQoL. Anxiety symptoms were the most potent independent correlate of most aspects of HRQoL. In addition, anxiety mediated the association between SOC and satisfaction with health, as well as its relationship with physical, mental, and social relations HRQoL. Depressive symptoms also mediated the association between SOC and mental HRQoL.CONCLUSION: Our data indicated that SOC is an important construct, as it influences psychological distress and has significant albeit indirect effects on several HRQoL domains in IBD. 相似文献
1000.
目的研究阿托伐他汀联合尿激酶溶栓对大鼠大脑中动脉急性脑梗死的疗效。方法选择SD大鼠48只,采用血栓栓塞法制备大鼠大脑中动脉急性脑梗死模型,随机分为阿托伐他汀组、尿激酶组、联合治疗组和对照组,每组12只。缺血3h给予阿托伐他汀或生理盐水,缺血4h给予尿激酶或生理盐水治疗。治疗前和缺血24h行神经功能缺损评分,缺血24h取脑行2,3,5-氯化三苯基四氮唑染色检测脑梗死体积。结果与对照组比较,阿托伐他汀组缺血24h神经功能显著改善[(6.5±4.3)分vs(12.5±4.3)分],脑梗死体积明显降低[(13.8±7.5)%vs(30.5±23.4)%,P<0.05]。与阿托伐他汀组比较,尿激酶组和联合治疗组神经功能改善程度及脑梗死体积降低程度更显著(P<0.05)。与尿激酶组比较,联合治疗组神经功能改善、脑梗死体积减小,但差异无统计学意义(P>0.05)。结论阿托伐他汀对脑梗死组织有保护作用,阿托伐他汀与尿激酶联合治疗有进一步提高疗效的趋势。 相似文献