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81.
82.
This study seeks to improve the mechanical performance of stents by conducting reliability performance testing and finite element method (FEM)‐based simulations for coronary stents. Three commercially available stent designs and our own new design were tested to measure the factors affecting performance, specifically foreshortening, recoil, radial force, and flexibility. The stents used in the present experiments were 3 mm in working diameter and 18 mm of working length. The results of the experiments indicate that the foreshortening of stents A, B, C, and our new design, D, was equivalent to 2.25, 0.67, 0.46, and 0.41%, respectively. The recoil of stents A, B, C, and D was 6.00, 4.35, 3.50, and 4.36%, respectively. Parallel plate radial force measurements were A, 3.72 ± 0.28 N; B, 3.81 ± 0.32 N; C, 4.35 ± 0.18 N; and D, 4.02 ± 0.24 N. Radial forces determined by applying uniform pressure in the circumferential direction were A, 28.749 ± 0.81 N; B, 32.231 ± 1.80 N; C, 34.522 ± 3.06 N; and D, 42.183 ± 2.84 N. The maximum force of crimped stent at 2.2‐mm deflection was 1.01 ± 0.08 N, 0.82 ± 0.08 N, 0.92 ± 0.12 N, and 0.68 ± 0.07 N for each of stents A, B, C and D. The results of this study enabled us to identify several factors to enhance the performance of stents. In comparing these stents, we found that our design, stent D, which was designed by a collaborative team from seven universities, performed better than the commercial stents across all parameter of foreshortening, recoil, radial force, and flexibility.  相似文献   
83.
Background and Aim: Adefovir add‐on therapy is recommended for patients infected with lamivudine‐resistant hepatitis B virus (HBV). We aimed to describe the long‐term treatment outcome and predictors for good response of adefovir add‐on therapy. Methods: A total of 559 chronic hepatitis B (CHB) patients who had been treated for at least 12 months with adefovir add‐on therapy due to resistance to lamivudine were retrospectively included. Complete virologic response (CVR) was defined as serum HBV DNA < 9 IU/mL. Viral responses at 6 months were classified as PCR negativity, partial virologic response (PVR, HBV DNA < 2000 IU/mL), or inadequate virologic response (IVR, HBV DNA ≥ 2000 IU/mL). Results: The median duration of follow‐up was 31.5 months (range, 12–56). The cumulative probabilities of CVR during adefovir add‐on therapy were 58%, 70%, 78%, and 80% at 12, 24, 36, and 43 months, respectively. The cumulative rates of resistance to adefovir were 0.4%, 0.8%, and 3.1% at 12, 24, and 36 months, respectively. The only baseline factor associated with CVR (hazard ratio 0.83, 95% confidence interval 0.62–0.91, P ≤ 0.001) and resistance to adefovir (hazard ratio 1.925, 95% confidence interval 1.13–3.30, P = 0.017) was serum HBV DNA level. Comparison of the cumulative rates of CVR and resistance to adefovir according to viral response at 6 months showed significant differences among the three groups (P < 0.0001 and P = 0.0005, respectively). Conclusions: Pre‐treatment HBV DNA level and viral response at 6 months is associated with treatment outcome for adefovir‐add on therapy in lamivudine resistance.  相似文献   
84.
Background and Aim: There are insufficient data on renal safety during long‐term adefovir dipivoxil (ADV) treatment. We aimed to elucidate the incidence and risk factors of renal impairment in chronic hepatitis B (CHB) patients treated with ADV. Methods: We retrospectively enrolled 687 CHB patients (51.4% with compensated cirrhosis) treated with ADV alone (18.2%) or in combination with lamivudine (81.8%) for more than 12 months. Renal function was measured using the estimated glomerular filtration rate (eGFR), and renal dysfunction was defined as mild (20–30% decrease), moderate (30–50%), or severe (more than 50%). Results: During the median treatment duration of 27 months, 72 patients (10.5%) developed renal impairment, which was mild in 77.8% of cases, moderate in 20.8% of cases, and severe in one patient. The cumulative incidence of renal impairment at 1, 3, and 5 years was 2.6%, 14.8%, and 34.7%, respectively. Modification of the dosing interval or discontinuation of ADV was required in seven and three patients, respectively, and none of them showed a further decline in the eGFR. Although a univariate analysis revealed age, the number of exposure to radio‐contrast dye, liver cirrhosis, and hepatocellular carcinoma as risk factors of renal impairment, age was the only significant risk factor identified in the multivariate analysis (odds ratio = 1.048, 95% confidence interval = 1.019–1.076, P = 0.001). Conclusions: Renal impairment in long‐term ADV users was relatively frequent, but serious renal toxicity was rare, and all cases were safely managed. Careful monitoring of renal function is required, especially in older patients.  相似文献   
85.
Background and Aim: Environmental factors such as food, lifestyle and prevalence of Helicobacter pylori infection are widely different in Asian countries compared with the West, and physiological functions and genetic factors of Asians may also be different from those of Westerners. Establishing an Asian consensus for functional dyspepsia is crucial in order to attract attention to such data from Asian countries, to articulate the experience and views of Asian experts, and to provide a relevant guide on management of functional dyspepsia for primary care physicians working in Asia. Methods: Consensus team members were selected from Asian experts and consensus development was carried out by using a modified Delphi method. Consensus teams collected published papers on functional dyspepsia especially from Asia and developed candidate consensus statements based on the generated clinical questions. At the first face‐to‐face meeting, each statement was reviewed and e‐mail voting was done twice. At the second face‐to‐face meeting, final voting on each statement was done using a keypad voting system. A grade of evidence and strength of recommendation were applied to each statement according to the method of the GRADE Working Group. Results: Twenty‐nine consensus statements were finalized, including seven for definition and diagnosis, five for epidemiology, nine for pathophysiology, and eight for management. Algorithms for diagnosis and management of functional dyspepsia were added. Conclusions: This consensus developed by Asian experts shows distinctive features of functional dyspepsia in Asia and will provide a guide to the diagnosis and management of functional dyspepsia for Asian primary care physicians.  相似文献   
86.
Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal-dominantly inherited disease that occurs in approximately one in 5000 to 8000 people. Clinical diagnosis of HHT is made when a person presents three of the following four criteria: family history, recurrent nosebleeds, mucocutaneous telangiectasis, and arteriovenous malformations (AVM) in the brain, lung, liver and gastrointestinal (GI) tract. Although epistaxis is the most common presenting symptom, AVMs affecting the lungs, brain and GI tract provoke a more serious outcome. Heterozygous mutations in endoglin, activin receptor-like kinase 1 (ACVRL1; ALK1), and SMAD4, the genes involved in the transforming growth factor-β family signaling cascade, cause HHT. We report here the case of a 63 year-old male patient who presented melena and GI bleeding episodes, proven to be caused by bleeding from multiple gastric angiodysplasia. Esophagogastroduodenoscopy revealed multiple angiodysplasia throughout the stomach. Endoscopic argon plasma coagulation was performed to control bleeding from a gastric angiodysplasia. The patient has been admitted several times with episodes of hemoptysis and hematochezia. One year ago, the patient was hospitalized due to right-sided weakness, which was caused by left basal ganglia hemorrhage as the part of HHT presentation. In family history, the patient's mother and elder sister had died, due to intracranial hemorrhage, and his eldest son has been suffered from recurrent epistaxis for 20 years. A genetic study revealed a mutation in exon 3 of ALK1 (c.199C > T; p.Arg67Trp) in the proband and his eldest son presenting epistaxis.  相似文献   
87.
Moon JH  Chae MK  Kim KJ  Kim HM  Cha BS  Lee HC  Kim YJ  Lee BW 《Circulation journal》2012,76(9):2273-2279
Background:?The aim of the present study was to investigate the serum levels of endothelial progenitor cells (EPCs) in type 2 diabetic patients without documented ischemic disease and the association between EPCs and atherosclerotic plaque formation in the carotid artery. Methods and Results:?A clinic-based, prospective study of type 2 diabetic patients was conducted. A total of 73 subjects were enrolled in this study after cardiac magnetic resonance imaging and ankle-brachial index measurements to exclude patients with ischemic disease. Plaque formation in the carotid artery was measured on ultrasonography. Circulating EPCs (CD34(+)/CD133(+)/CD309(+) cells) were counted on flow cytometry. Compared to subjects without carotid artery plaques, patients with plaques were significantly older (P=0.006) and had decreased EPC count (P=0.027). Serum glycated albumin (GA) level and the GA/glycated hemoglobin ratio tended to decrease in patients with plaques (P=0.091 and 0.067, respectively). Other cardiovascular disease risk factors were not significantly different between the 2 groups. On binary logistic regression analysis old age, low EPC count, and high serum GA level were independently correlated with carotid artery plaque formation. Conclusions:?EPC count and serum GA level appear to be a protective and an aggravating factor for endothelial damage, respectively, and therefore, a reduced EPC count or an increased GA level results in atherosclerotic plaque formation in type 2 diabetic patients. (Circ J?2012; 76: 2273-2279).  相似文献   
88.
Phlebosclerotic colitis is a rare disease of intestinal ischemia caused by calcified peripheral mesenteric veins and a thickened colonic wall, differentiating it from the typical ischemic colitis. A 68-year-old man who was undergoing hemodialysis presented with hematochezia and abdominal pain. Colonoscopic findings showed typical dark purple-colored edematous mucosa. Linear calcifications in the colon were noted on both a plain abdominal radiolography and abdominal computer tomography. These findings suggested that the patient suffered from phlebosclerotic colitis. Following bowel rest and fluid therapy, there was full recovery. We herein report a rare case of phlebosclerotic colitis in a hemodialysis patient and include a review of the relevant literature.  相似文献   
89.

Purpose

We investigated the treatment outcomes according to neuropathic bladder sphincter dysfunction (NBSD) type after oral oxybutynin (OBT) treatment in children with NBSD caused by myelodysplasia.

Methods

Among 334 pediatric patients who were diagnosed with NBSD caused by myelodysplasia, only children treated with oral OBT for more than 1 year with pre- and post-treatment urodynamic studies and dimercaptosuccinic acid (DMSA) were retrospectively reviewed. We compared pre- and post-treatment urodynamic parameters including maximum cystometric capacity (MCC), MCC/estimated bladder capacity (EBC), and compliance by NBSD type in children. We also compared renal scarring on pre- and post-treatment DMSA by NBSD type in children.

Results

Our study population was comprised of 81 children (45 boys and 36 girls), with a mean age of 4.2 ± 3.4 years. The mean follow-up duration was 4.5 (range 1.0–15.1) years. After OBT treatment, MCC was increased significantly in all types of NBSD from 110.3 ± 62.2 to 202.3 ± 103.9 ml (p < 0.05), compliance was significantly improved from 6.4 ± 6.1 to 11.1 ± 9.6 ml/cmH2O (p < 0.05), but MCC/EBC was slightly decreased from 75.2 ± 46.9 to 69.8 ± 33.3 % (p = 0.40). Sub-analyzed by NBSD type, the pre-treatment compliance of children with acontractile detrusor with spastic sphincter (n = 16) was markedly decreased compared with other types of NBSD. Acontractile detrusor with spastic sphincter demonstrated the worst renal deterioration on DMSA.

Conclusions

Although increases in MCC/EBC were limited, oral OBT treatment markedly improved MCC and compliance in all NBSD types. Children who had acontractile detrusor with spastic sphincter had a relatively high probability of renal deterioration and required specific attention.  相似文献   
90.

Background

Little is known of the oncological outcomes after adjuvant FOLFOX chemotherapy in patients with stage III colon cancer showing microsatellite instability high (MSI-H). In the present study we investigated the prognostic impact of MSI-H in patients with stage III colon cancer receiving FOLFOX chemotherapy.

Methods

We analyzed the MSI status in 127 patients with stage III colon cancer who underwent curative surgical resection followed by FOLFOX chemotherapy between January 2003 and December 2010. We assessed disease-free and overall survival (OS) in patients with MSI-H colon cancer compared with those showing microsatellite instability low or microsatellite stable (MSI-L/MSS) disease.

Results

Sixteen of the patients (12.6 %) were MSI-H, and 111 patients (87.4 %) were MSI-L/MSS. There was no significant difference between patients showing MSI-H and MSI-L/MSS except for age (P = 0.030), tumor location (P < 0.001), and differentiation (P = 0.031). Compared with MSI-L/MSS colon cancer, patients with MSI-H colon cancer had no significant difference in 5-year disease-free and OS (72.2 vs 68.5 %, P = 0.874; 68.1 vs 71.1 %, P = 0.437).

Conclusions

Our study indicates that FOLFOX chemotherapy can be considered to treat stage III colon cancer patients with MSI-H after surgery, although the study was not randomized and included only a limited number of patients.  相似文献   
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