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1.
Background and purpose — Total ankle arthroplasties (TAAs) have larger revision rates than hip and knee implants. We examined the survival rates of our primary TAAs, and what different factors, including the cause of arthritis, affect the success and/or revision rate.Patients and methods — From 2004 to 2016, 322 primary Hintegra TAAs were implanted: the 2nd generation implant from 2004 until mid-2007 and the 3rd generation from late 2007 to 2016. A Cox proportional hazards model evaluated sex, age, primary diagnosis, and implant generation, pre- and postoperative angles and implant position as risk factors for revision.Results — 60 implants (19%) were revised, the majority (n = 34) due to loosening. The 5-year survival rate (95% CI) was 75% (69–82) and the 10-year survival rate was 68% (60–77). There was a reduced risk of revision, per degree of increased postoperative medial distal tibial angle at 0.84 (0.72–0.98) and preoperative talus angle at 0.95 (0.90–1.00), indicating that varus ankles may have a larger revision rate. Generation of implant, sex, primary diagnosis, and most pre- and postoperative radiological angles did not statistically affect revision risk.Interpretation — Our revision rates are slightly above registry rates and well above those of the developer. Most were revised due to loosening; no difference was demonstrated with the 2 generations of implant used. Learning curve and a low threshold for revision could explain the high revision rate.

Arthritis in the ankle often develops earlier than in the hip or knee, and 70% have a traumatic etiology (Saltzman et al. 2005, Brown et al. 2006). Total ankle arthroplasty (TAA) can be indicated for severe arthritis in the ankle joint, but the anatomical preconditions, like a small surface area and high stress from compression and torque (Bouguecha et al. 2011, Kakkar and Siddique 2011), makes it less durable than hip and knee prosthetics. The Hintegra TAA, a 3-component mobile bearing, uncemented implant (Hintermann et al. 2004) is widely used and results from the development center demonstrate survival rates of 94% and 84% after 5 and 10 years’ follow-up (Barg et al. 2013). This is considerably more than the survival rates from national registries. Labek et al. (2011) demonstrated that development centers report only half of the revision rate that can be found in the few existing national registers. In a systematic review of primary Agility total ankle arthroplasty (DePuy Synthes Orthopedics, Warsaw, IN, USA), the author (Roukis 2012) found that the incidence of complications increased from 7% to 12%, in studies where the inventor was excluded. Similar results were found by Prissel and Roukis (2013), who found an increased incidence of complications from 6% to 13% in studies where the inventor or faculty consultants were excluded. These studies indicated the risk of selection (inventor) and publication (conflict of interest) bias.Planning and surgical technique, including significant experience, are mandatory for a successful outcome. The better result from development centers may reflect, besides the above-mentioned bias, that there is a long learning curve and that the indication for revision surgery varies.We examined the survival rates of primary Hintegra TAAs performed at Hvidovre Hospital, with revision rate as outcome. We report primary diagnosis for primary TAA and examine whether sex, generation of the implant, preoperative angles and implant position affect the revision rate.  相似文献   
2.
Background: There are some unique epidemiological characteristics of esophageal cancer in Iran. The objective of this study was finding the association between tobacco, substance and alcohol using with the risk of esophageal cancer in North Khorasan, Iran.

Methods: This Case-Control study was carried out on 96 patients with esophageal cancer and 187 controls. Controls were matched to cases by age and sex. Data were collected through structured interview. Data were analyzed by using chi-square test, T-test and logistic regression, in Stata software version 12.

Results: Our findings show Hookah smoking [OR = 6.1(CI95%:1.2–13.1)] and opium consumption [OR = 2.1(CI95%:1.2–3.5)] were associated with esophageal cancer. Cigarette and pipe smoking, age of onset of smoking, duration of smoking, number of smoking per day, leaving history of smoking, years of leaving smoking, drug withdrawal, number of times of drug withdrawal, a history of drug relapse, alcohol consumption and alcohol dose–response were not related to esophageal cancer.

Conclusion: According to our results, hookah smoking and opium consumption enhance the risk of esophageal cancer in North Khorasan of Iran. We suggest appropriate planning to prevent the esophageal cancer in this district.  相似文献   

3.
4.
We study the image formation of vibro-acoustography systems based on a concave sector array transducer taking into account depth-of-field effects. The system point-spread function (PSF) is defined in terms of the acoustic emission of a point-target in response to the dynamic radiation stress of ultrasound. The PSF on the focal plane and the axis of the transducer are presented. To extend the obtained PSF to the 3D-space, we assume it is a separable function in the axial direction and the focal plane of the transducer. In this model, an image is formed through the 3D convolution of the PSF with an object function. Experimental vibro-acoustography images of a breast phantom with lesion-like inclusions were compared with simulated images. Results show that the experimental images are in good agreement with the proposed model.  相似文献   
5.
Human and animal studies have implicated dopamine in appetite regulation, and family studies have shown that BMI has a strong genetic component. Dopamine availability is controlled largely by three enzymes: COMT, MAOA and MAOB, and by the dopamine transporter SLC6A3, and each gene has a well-characterized functional variant. Here we look at these four functional polymorphisms together, to investigate how heritable variation in dopamine levels influences the risk of obesity in a cohort of 1150, including 240 defined as obese (BMI ≥ 30). The COMT and SLC6A3 polymorphisms showed no association with either weight, BMI or obesity risk. We found, however, that both MAOA and MAOB show an excess of the low-activity genotypes in obese individuals ( MAOA: χ2= 15.45, p = 0.004; MAOB: χ2= 8.05, p = 0.018). Additionally, the MAOA genotype was significantly associated with both weight (p = 0.0005) and BMI (p = 0.001). When considered together, the 'at risk genotype' - low activity genotypes at both the MAOA and MAOB loci - shows a relative risk for obesity of 5.01. These results have not been replicated and, given the experience of complex trait genetics, warrant caution in interpretation. In implicating both the MAOA and MOAB variants, however, this study provides the first indication that dopamine availability (as opposed to other effects of MAOA) is involved in human obesity. It is therefore a priority to assess the associations in replication datasets.  相似文献   
6.
Head trauma     
Computed tomography is currently the modality of choice in imaging acutely traumatized patients. This is based upon CT's documented ability to detect surgically significant lesions. Furthermore, the use of MRI is limited by a lack of bone detail, the degradation of MR images in frequently uncooperative patients, and a limited supply of nonferromagnetic monitoring equipments. CT and MRI are largely equivalent in their ability to diagnose epidural hematoma, but CT is readily available and quick. MRI provides information in addition to that obtained by CT in many instances, such as subacute and chronic subdural hematomas, contusions, and intracerebral hematomas.  相似文献   
7.
Radioimmunoassays (RIAs) have been used to detect the promutagenic lesion O6-methyldeoxyguanosine (O6-MedG) in DNA isolated from the bladder tissues of Egyptian patients presenting with bladder carcinoma and concomitant schistosomiasis (bilharziasis), a parasitic disease known to be associated with the presence of N-nitrosamines in the urine. Alkylation damage was present in the DNA of the majority of the samples (44/46, 96%); 38 samples were of tumour tissue and 8 from uninvolved bladder mucosa. Levels of O6-MedG ranged from undetectable (ND; i.e. less than 0.01 mumol O6-MedG/mol dG) to 0.485 mumol/mol dG with an overall mean of 0.134 +/- 0.10 mumol/mol dG, including the two samples that were below the limit of detection. In contrast, methylation damage was detected in only 4/12 (33%) of the DNA samples from normal bladder tissue of European origin. In these samples levels of O6-MedG ranged from ND to 0.225 mumol/mol dG with an overall mean of 0.046 +/- 0.082 mumol O6-MedG/mol dG. These results confirm that alkylation events can be detected in the DNA of schistosome-infected human bladder tissue. The methylation of uninvolved and tumour tissue DNA to similar extents suggests that the alkylating intermediate may have been present in the urine. These results indicate the need for further investigation to determine whether relationships exist between levels of DNA damage and the prevalence of schistosome infection and/or the extent and type of bacterial infection that frequently accompanies this disease.  相似文献   
8.
9.
MR imaging of neurocysticercosis   总被引:1,自引:0,他引:1  
Magnetic resonance (MR) was performed in 50 patients with neurocysticercosis. Comparison was made with other neuroradiological imaging modalities including CT, myelography, CT ventriculography, and CT myelocisternography. Eighteen patients were found to have intraventricular cysts. In several patients, these were multiple and 22 intraventricular cysts were discovered. Although 4 of the 22 ventricular cysts were missed by MR, T1-weighted images can play a significant role in the early detection of intraventricular cysticercosis cysts, showing the cyst wall (9 of 22), a high intensity mural nodule (6 of 22), and increased signal intensity of the cyst fluid (5 of 22). Cisternal cysts (14 cysts in 10 patients) could be identified; they appear similar to intraventricular cysts, but mural nodules are infrequently seen (1 of 14). Twenty-nine patients had 69 parenchymal cysts. An attempt was made to assess the viability of these parenchymal lesions by matching the CT and MR findings with the Escobar pathologic staging system. Neuroimaging findings seemed compatible with early parenchymal lesions in the vesicular stage in 11 instances. Findings in cases with later stage cysts tend to support the concept that a dying larva provokes pronounced inflammatory reaction in the adjacent brain. Computed tomography remains the superior modality for depicting parenchymal calcifications within dead larvae. A case of a spinal cysticercosis cyst demonstrated with MR (in a patient with extensive intracranial cisternal cysts and a fourth ventricular cyst) is described.  相似文献   
10.
Between 1984 and 1986 six patients with acute respiratory failure (requiring ventilation for at least 3 days) complicating acute pancreatitis were managed on the intensive care unit (median ventilation period 6 days; range 3-41 days). Between 1987 and 1989 nine similar patients were managed (median ventilation period 35 days, range 4-69 days), and a regimen of enteral tobramycin, polymyxin and amphotericin to selectively decontaminate the digestive tract (SDD) was introduced. Five of six patients treated before 1987 had serious infections (three Gram-negative, one fungal), compared with only one of nine patients treated with SDD (P < 0.05). Clinical signs of sepsis were evident for 62% of the pre-SDD period, compared with 39% of the period during SDD therapy (P < 0.001). Systemic antibiotic prescribing was reduced in the SDD group; however, mortality remained unaffected with only two patients surviving pre-SDD and three during SDD treatment. SDD reduces infection rates and sepsis in patients with acute pancreatitis and may help to improve the prognosis of this life-threatening condition.  相似文献   
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