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41.
IntroductionSome improvements have been developed with new generations of nickel-titanium (NiTi) rotary instruments that led to their successful and extensive application in clinical practice. The purpose of this in vitro study was to compare the root canal preparations performed by using GT Series X and Twisted File systems produced by innovative manufacturing process with Revo-S, RaCe, Mtwo, and ProTaper Universal systems manufactured directly from conventional nitinol and with stainless steel K-Flexofile instruments.MethodsThe mesiobuccal root canals of 140 maxillary first permanent molars that had between 30°–40° curvature angle and 4- to 9-mm curvature radius of the root canal were used. After root canal preparations made by using GT Series X, Twisted File, Revo-S, RaCe, Mtwo, and ProTaper Universal NiTi rotary systems and stainless steel K-Flexofile instruments, transportation occurred in the root canal, and alteration of working length (WL) was assessed by using a modified double-digital radiographic technique. The data were compared by the post hoc Tukey honestly significant difference test.ResultsNiTi rotary systems caused less canal transportation and alteration of WL than K-Flexofile instruments (P < .05). There was no significant difference between NiTi rotary system groups at any levels (P > .05) except 2.5 mm from the WL. At this level ProTaper Universal system caused significant canal transportation (P < .05).ConclusionsGT Series X and Twisted File rotary systems produced with innovative process were concluded to shape the curved canals to result in minimal canal transportation, similar to Revo-S, RaCe, Mtwo, and ProTaper Universal rotary systems manufactured by traditional methods. 相似文献
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43.
Nazih H Raffi F Taïeb A Reynes J Choutet P Cassuto JP Ferry T Chêne G Leport C Bard JM;Aproco-Copilote Anrs Co Study Group 《AIDS research and human retroviruses》2012,28(4):393-399
Highly active antiretroviral therapy (HAART) is associated with fat redistribution and metabolic disorders. The present study was undertaken to evaluate the association between peroxisome proliferator activated receptor (PPAR)α and PPARγ polymorphisms, two genes involved in lipid metabolism and adipocyte differentiation, and elements of the metabolic syndrome, lipodystrophy, or carbohydrate metabolism abnormalities in patients receiving HAART. The frequency distribution of rare alleles for PPARα (L162V) and PPARγ (P12A and H449H) was compared using the chi square test in 363 HIV-1-infected patients classified according to the presence or absence of the metabolic syndrome after 48 months of follow-up on their first PI-containing regimen. The P12A rare g allele was present in 12% patients with normal glucose metabolism, 11% patients with impaired glucose tolerance or impaired fasting glucose, and 35% patients with diabetes (p=0.014). The rare g allele for L162V was present in 14% of patients free of hypertriglyceridemia and in 7% patients with hypertriglyceridemia (p=0.04). The rare g allele for L162V was found in 15% of patients free of any sign of lipodystrophy and 8% with at least one sign of lipodystrophy (p=0.04) and the rare t allele for H449H was found in 14% of patients free of any sign of lipodystrophy and 23% of patients with at least one sign of lipodystrophy (p=0.05). There was no convincing association between any polymorphism of PPARα and PPARγ and each individual component of the metabolic syndrome, except for the relationship of the P12A polymorphism with diabetes. Confirmatory studies on a larger number of individuals are needed. 相似文献
44.
Dong Ta Zhong Chun Mei Shi Qiang Chen Jing Ze Huang Jian Gang Liang 《Annals of hematology》2012,91(11):1757-1763
Non-Hodgkin's lymphoma (NHL) remains the second most common malignant complication in patients with human immunodeficiency virus (HIV) infection. Even though NHL is commonly chemosensitive to primary treatment, failure or relapse still occurs in a large number of patients. We conducted this retrospective study to evaluate the efficacy and safety of gemcitabine, dexamethasone, and cisplatin (GDP) for relapsed or refractory AIDS-related NHL (AIDS-NHL). Forty-eight patients with relapsed or refractory AIDS-NHL were treated with intravenous combination chemotherapy with GDP. The overall objective response rate was 54.1?% (95?% confidence interval, CI, 40.1–68.3?%), with 10 complete responses and 16 partial responses. The 2-year overall survival rate (OS) was 70.8?% (95?% CI 58.0–83.7?%), and the 5-year OS was 41.7?% (95?% CI 27.7–55.6?%). The 2-year progression-free survival rate (PFS) was 37.5?% (95?% CI 23.8–51.2?%), and the 5-year PFS was 25.0?% (95?% CI 12.8–37.3?%). The median progression-free survival was 8.8?months (95?% CI 0–20.3?months), and the median overall survival was 40.6?months (95?% CI 22.6–58.6?months). Patients with B cell tumors who relapsed but had no B symptoms were clinical stage I/II, had infiltration fewer than two extranodal sites, had CD4+ counts >200 cells/μL, and had lactate dehydrogenase (LDH) less than the upper limit of normal benefited from GDP. The level of LDH had a significant impact on the response rate to chemotherapy with GDP (P?=?0.015). Myelosuppression was the main side effect; the incidence of grade 3–4 anemia was 8.3?%; leukopenia, 37.5?%; and thrombocytopenia, 48.3?%. Univariate and multivariate analyses were performed to determine variables for OS and PFS. This study confirms that GDP is an effective and safe salvage regimen in relapsed or refractory AIDS-NHL, was associated with modest declines in CD4+ lymphocyte counts, and did not promote HIV-1 viral replication. 相似文献
45.
Endoscopic transsphenoidal surgery is emerging as a minimally invasive and maximally effective procedure for pituitary adenomas. In this report we analyzed the complications in 624 procedures of endonasal transsphenoidal endoscopic surgery in the treatment of 570 patients with pituitary adenomas. The leading author (MB) operated pituitary adenomas via pure endoscopic endonasal transsphenoidal surgery between January 2006 and August 2011 at the Hacettepe University, Department of Neurosurgery in Ankara. Complications were assessed in 624 surgical procedures under five groups; rhinological, CSF leaks, infection, vascular and endocrinologic complications. We observed a total of 76 complications (12.1%). Rhinological complications occurred in 8 patients (1.3%): 4 epistaxis (0.6%) and 4 hyposmia (0.6%). Postoperative CSF leaks occurred in 8 patients (1.3%), and infectious complications occurred in 8 patients: 3 cases of sphenoidal sinusitis (0.4%), 5 cases of meningitis (0.8%). Only 1 case of internal carotid aneurysm rupture during the opening of sellar floor (0.16%) was observed. Endocrinologic complications occurred in 51 (8.1%) patients: Anterior pituitary deficiency in 12 (1.9%), transient diabetes insipidus (DI) in 29 (4.6%), permanent DI in 3 (0.4%) and inappropriate antidiuretic hormone secretion syndrome occurred in 7 (1.1%). There was no mortality directly related to the surgical procedure. The complication rates observed in our study suggests that the endoscopic pituitary surgery is at least as safe as microscopic transphenoidal surgery. These rates were obtained with due experience and well-coordinated teamwork. To further improve these rates, new technological developments will be helpful. 相似文献
46.
In order to determine the prognostic impact of lymphovascular invasion (LVI) in patients after radical prostatectomy, the retrospective data from our institution has been analyzed. From 1998 to 2010, 117 patients underwent radical prostatectomy. A total of 87 patients were included in this retrospective study. The relationship between LVI and advanced prostate cancer characteristics was evaluated by χ(2) test. The Kaplan-Meier method and meta-analysis were used to describe the impact of LVI invasion upon early biochemical failure after radical prostatectomy. LVI was observed in patients with clinically or pathologically aggressive prostate cancer including patients of higher preoperative risk group, higher preoperative PSA, advanced Gleason grade, and pathological T3 disease. LVI is also associated with early biochemical failure rate both in our report and in the literature. Therefore, LVI is a pathological feature which indicates prognosis correlates with aggressive prostate cancer behavior and results in early biochemical failure after radical prostatectomy. 相似文献
47.
Hao Lun Luo MD Chih Hsiung Kang MD Yen Ta Chen MD Yao Chi Chuang MD Wei Ching Lee MD Yuan Tso Cheng MD Po Hui Chiang PhD MD 《Annals of surgical oncology》2013,20(9):3121-3126
Background
Little is known about the effects of diagnostic ureteroscopy on intravesical recurrence after nephroureterectomy.Methods
This study was designed to determine the effect of diagnostic ureteroscopy on intravesical recurrence after nephroureterectomy. From 2004 to 2010, 446 patients underwent nephroureterectomy for upper urinary tract cancer at our tertiary medical center. We included 115 patients who underwent preoperative diagnostic ureteroscopy and 281 patients who did not. This study analyzed the impact of the reported risk factors and diagnostic ureteroscopy for intravesical recurrence after nephroureterectomy by multivariate Cox regression model.Results
The rates of metastasis and cancer-specific mortality did not differ significantly between the two groups. Diagnostic ureteroscopy was associated with a higher incidence of intravesical recurrence in patients with (p = 0.02) and without (p = 0.016) a previous history of bladder cancer. Ureter tumor biopsy (p = 0.272) and ureter involvement (p = 0.743) were not associated with the rate of intravesical recurrence in this study. Multivariate Cox regression analysis showed that only bladder cancer history (p < 0.001), multifocal tumor (p = 0.05), and diagnostic ureteroscopy (p = 0.05) were independently associated with intravesical recurrence.Conclusions
Diagnostic ureteroscopy for upper urinary tract cancer was not associated with metastasis and cancer-specific mortality. However, ureteroscopy was associated with an increased incidence of intravesical tumor recurrence. Methods of prevention should be considered to decrease intravesical recurrence and avoid repeated surgical interventions or the development of advanced bladder disease in patients at risk. 相似文献48.
Marvin A. Tañag Satoshi Takagi Mariko Takashima Kunihiro Nakai Yasuo Sakai Kenji Yano 《Journal of plastic surgery and hand surgery》2013,47(5):259-263
We report a rare case of visual improvement in a 19-year-old patient with Apert syndrome after segmental distraction with a rigid external distraction device. We used the Rigid External Distraction Device II System (R.E.D. II, KLS Martin) after Le Fort I and III osteotomies. 相似文献
49.
Background: Several studies have shown a possible association between periodontal disease and obesity. The aim of this study is to evaluate serum plasminogen activator inhibitor 1 (PAI‐1), tumor necrosis factor‐alpha (TNF‐α), and high‐sensitivity C‐reactive protein (hsCRP) levels in the association between obesity and periodontal disease. Methods: Two hundred individuals participated in this study. Body mass index (BMI), waist‐to‐hip ratio, plasma triglyceride (TRG), total cholesterol, low‐density lipoprotein cholesterol, high‐density lipoprotein cholesterol (HDL‐C), fasting blood glucose (FBG), hsCRP, TNF‐α, PAI‐1, and periodontal parameters (including plaque index [PI], probing depth [PD], clinical attachment level [CAL], and percentage of sites with bleeding on probing) were evaluated. Results: The groups with BMI ≥ 25 had higher median values for FBG, TRG, hsCRP, PAI‐1, PI, and CAL than did the groups with a BMI < 25 (P <0.01). Serum TRG levels were positively correlated with PI, PD, and CAL. There were negative associations between clinical periodontal parameters and HDL‐C. There were statistically significant correlations between PAI‐1 and clinical periodontal parameters (PI, PD, and CAL). Conclusion: Serum PAI‐1 levels may play an important role in the association between periodontal disease and obesity. 相似文献
50.