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991.
992.
ObjectivesThe aim of this prospective controlled study was to determine the role that the lateral cephalogram can play in the detection of palatally displaced canines (PDCs).Materials and methodsThe study was comprised of 85 subjects in the late mixed dentition. Thirty-five subjects had PDCs (either unilateral or bilateral) identified on the panoramic radiograph (PDC group), and 50 subjects presented with a normal pathway of upper permanent canine eruption as assessed on panoramic radiographs (No-PDC group). Linear and angular measurements on the lateral cephalograms concurrent with panoramic radiographs were compared between the PDC and No-PDC group statistically.ResultsAll angular measurements that incorporated the main axis of the canine (to Frankfort horizontal, to the palatal plane, or to the axis of the central incisor) were significantly smaller in the PDC group (p<0.001). In terms of linear measurements, both the distance from the tip of the canine to the vertical axis of the central incisor parallel to Frankfort horizontal and the distance from the tip of the canine to the anterior alveolar ridge parallel to Frankfort horizontal showed significantly larger values in the PDC subjects than in normal controls. On the contrary, the vertical distance from the tip of the canine to the functional occlusal plane did not reveal any significant difference between the PDC and the No-PDC group.ConclusionsEarly diagnosis of PDC is essential in order to avoid the occurrence of final canine impaction. If 3-D images of a displaced canine cannot be acquired, a lateral cephalogram can be a useful tool for the early detection of PDC in the late mixed dentition. The angle between the vertical axis of the canine and the palatal plane demonstrate diagnostic value when assessing PDCs. Values for this angle smaller than 102 degrees can indicate the presence of PDC.  相似文献   
993.
Cardiovascular magnetic resonance (CMR) of the superficial femoral artery (SFA) allows direct and noninvasive visualization of atherosclerotic plaque burden. We examined atherosclerosis in 3 groups of patients without history or symptoms of peripheral arterial disease with varying expected burdens: those with diabetes mellitus (DM) and known coronary artery disease (CAD) (n = 24), those with DM and a high prevalence of CAD risk factors (n = 20), and controls of similar age without DM or CAD and few CAD risk factors (n = 15). We also assessed the diagnostic accuracy of this technique to differentiate among these 3 groups. T1-weighted spin-echocardiographic images were used to measure mean wall thickness (WT) and total wall volume indexed to total vessel volume. Diagnostic accuracy was assessed by area under receiver operating characteristics curve analysis. Patients with DM plus risk factors and DM plus CAD had higher mean WT (1.28 and 1.37 mm) and mean indexed wall volume (0.53 and 0.56) compared to controls (mean WT 1.16 mm and mean indexed wall volume 0.45; p <0.010 for all comparisons). Mean WT and indexed wall volume showed good diagnostic accuracy in discriminating controls from those with DM plus CAD (areas under curve 0.85 and 0.87, respectively, p <0.001), whereas only indexed wall volume discriminated DM plus risk factors from controls (area under curve 0.82, p <0.001). Neither could discriminate between DM plus risk factors and DM plus CAD. In conclusion, patients with DM plus risk factors and DM plus CAD had significantly greater atherosclerotic burden in the SFA on CMR imaging than controls of similar age, with good diagnostic accuracy in differentiating these groups. The high reproducibility and reliability of CMR of the SFA may facilitate improved assessment of atherosclerosis prevalence and progression/regression in studies of novel therapies.  相似文献   
994.
Graft‐versus‐host disease (GvHD) is a common complication following haematopoietic stem cell transplant but little is published about the impact of this condition on hospital readmission rates. We report a retrospective analysis of readmission rates and associated costs in 187 consecutive allogeneic transplant patients to assess the impact of GvHD. The overall readmission rate was higher in patients with GvHD (86% (101/118) vs. 59% (41/69), p < 0.001). The readmission rate was higher both in the first 100 d from transplant (p = 0.02) and in the first year following transplant (p < 0.001). 151/455 (33%) of all readmission episodes occurred within 100 d of transplant. The mean number of inpatient days was significantly higher in patients with grade III/IV acute GvHD (101 d) compared with those with grade I/II GvHD (70 d; p = 0.003). The mean cost of readmission was higher in patients with GvHD (£28 860) than in non‐GvHD patients (£13 405; p = 0.002) and in patients with grade III/IV GvHD (£40 012) compared with those patients with grade I/II GvHD (£24 560; p = 0.038). Survival was higher in those with grade I/II GvHD (55%) compared to grade III/IV GvHD (14%; p < 0.001). This study shows the high economic burden and poor overall survival associated with grade III/IV GvHD.  相似文献   
995.

Background

Following a national audit of rectal cancer management in 2007, a national centralization program in the Republic of Ireland was initiated. In 2010, a prospective evaluation of rectal cancer treatment and early outcomes was conducted.

Methods

A total of 29 colorectal surgeons in 14 centers prospectively collated data on all patients with rectal cancer who underwent curative surgery in 2010.

Results

Data were available on 447 patients who underwent proctectomy with curative intent for rectal cancer in 2010; 23.7 % of patients underwent abdominoperineal excision. The median number of lymph nodes identified was 12. The 30-day mortality rate was 1.1 %. Compared with 2007, there was a reduction in positive circumferential margin rate (15.8 vs 4.5 %, P < 0.001), clinical anastomotic leak rate (10.8 vs 4.3 %, P = 0.002), and postoperative radiotherapy use (17.8 vs 4.0 %, P < 0.001). Also, 53.9 % received preoperative radiotherapy in 2010. Four centers gave statistically more patients (high-administration), and four centers gave fewer patients (low-administration) preoperative radiotherapy for T2/T3 tumors (P < 0.05). On multivariate analysis, being treated in a “high-administration center” increased the likelihood (likelihood ratio [LR], 2.9; 95 % CI 1.7–4.8; P < 0.001) while attending a “low-administration center” (LR, 0.3; 95 % CI 0.2–0.5; P < 0.001) reduced the likelihood of receiving preoperative radiotherapy for a T2/T3 rectal cancer.

Conclusions

Patients undergoing rectal cancer surgery in hospitals following a national centralization initiative received high-quality surgery. Significant heterogeneity exists in radiotherapy administration, and evidence-based guidelines should be developed and implemented.  相似文献   
996.
997.
998.
The microvasculature is a vital organ that distributes nutrients within tissues, and collects waste products from them, and which defines the environmental conditions in both normal and disease situations. Here, a microfluidic chip was developed for the fabrication of poly(ethylene glycol diacrylate) (PEGDA)-based hollow self-standing microvessels having inner dimensions ranging from 15 μm to 73 μm and displaying biocompatibility/cytocompatibility. Macromer solutions were hydrodynamically focused into a single microchannel to form a concentric flow regime, and were subsequently solidified through photopolymerization. This approach uniquely allowed the fabrication of hollow microvessels having a defined structure and integrity suitable for cell culturing.

Biocompatible and self-standing poly(ethylene glycol diacrylate)-based hollow microvessels were fabricated from a microfluidic device using microfluidic principles.  相似文献   
999.
1000.
Objectives: To assess the cross‐cultural validity of two Kessler psychological distress scales (K‐10 and K‐5) by examining their measurement properties among older Aboriginal and Torres Strait Islanders and comparing them to those in non‐Aboriginal individuals from NSW Australia. Methods: Self‐reported questionnaire data from the 45 and Up Study for 1,631 Aboriginal and 231,774 non‐Aboriginal people were used to examine the factor structure, convergent validity, internal consistency and levels of missing data of K‐10 and K‐5. Results: We found excellent agreement in classification of distress of Aboriginal participants by K‐10 and K‐5 (weighted kappa=0.87), high internal consistency (Cronbach's alpha K‐10: 0.93, K‐5: 0.88), and factor structures consistent with those for the total Australian population. Convergent validity was evidenced by a strong graded relationship between the level of distress and the odds of: problems with daily activities due to emotional problems; current treatment for depression or anxiety; and poor quality of life. Conclusions and implications: K‐10 and K‐5 scales are promising tools for measuring psychological distress among Aboriginal and Torres Strait Islanders aged 45 and over in research and clinical settings.  相似文献   
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