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81.
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83.
有关不同覆深度者的解剖形态和肌肉功能差异的研究,已有诸多文献报道.曲面断层片是正畸诊断中最常用的X线检查手段之一.本项研究的目的是探讨不同覆深度者的髁突形态在曲面断层片中有何差异,不同髁突形态类型在正常和不同覆错畸形患者中的分布如何.  相似文献   
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Bone mineral density (BMD) and content (BMC) were measured in nine children treated with corticosteroids for nephrotic syndrome and in age-matched controls, using dual-energy X-ray absorptiometry (DEXA). The urinary excretion of cross-linked N-telopeptide (NTx) released from collagen type I as a specific marker of bone resorption was also measured. There were no significant differences in body size, BMD results or NTx urinary concentrations between patients and controls, nor could any significant differences be found when the six patients given a cumulative corticosteroid dose of >15 g were analysed separately. The lack of significant differences could be due to the small number of patients included in the study. But when the measured BMD and BMC were analysed according to methods that corrected for body size and puberty stage, values well within the normal range were found in patients as well as in controls. There was, however, a significant, negative correlation between the urinary excretion of NTx and the cumulative dose of corticosteroids. CONCLUSION: Despite treatment for long periods with high, cumulative doses of corticosteroids, the skeletons of the patients had a normal mineral content, which is encouraging for all those in need of steroids for nephrotic syndrome. A negative correlation between urinary collagen degradation products and the cumulative steroid dose might point to a reduced growth velocity in patients on high doses of steroids earlier than an effect on bone mineralization.  相似文献   
87.

Background

The prognostic impact of occluded culprit arteries in non‐ST‐elevation myocardial infarction (NSTEMI) patients beyond 12 months has not been investigated.

Objectives

The impact of occluded culprit arteries on a composite of cardiac death (CD), recurrent nonfatal MI (RMI), and target vessel revascularization (TVR) in patients who presented with NSTEMI was investigated during a 48‐month follow‐up using propensity‐score (PS) matching.

Methods

A total of 2,878 NSTEMI patients in the COREA‐AMI (COnvergent REgistry of cAtholic and chonnAm university for Acute MI) Registry were classified according to the angiographic flow of culprit arteries (occlusion [OC], n = 1,070; nonocclusion, n = 1,808). After PS matching, the incidence of the primary end‐point, a composite of CD, RMI, and TVR was compared.

Results

The median follow‐up duration was 47.3 months (IQR 32.7–66.2). In the PS‐matched population, the 48‐month cumulative rates of the primary end‐point (27.5% vs. 17.9%, P < 0.001) and each event were higher in the OC group (CD: 9.0% vs. 5.4%, RMI: 16.3% vs. 9.4%, TVR: 10.5% vs. 5.6%, respectively, P < 0.05). In multivariate Cox regression analysis, occluded culprit arteries showed the significant statistical impact on the primary end‐point (HR 1.689 [1.385–2.059], P < 0.001) and each event (CD: 1.736 [1.218–2.475], RMI: 1.918 [1.468–2.505], TVR: 2.042 [1.453–2.869], respectively, P < 0.05). Furthermore, in the 12‐month landmark analysis, occluded culprit arteries were still associated with higher risk of primary end‐point beyond 12 months (P < 0.001).

Conclusions

Occluded culprit arteries were independently associated with the higher risk of CD, RMI, and TVR in NSTEMI patients during the 48‐month follow‐up. (J Interven Cardiol 2014;27:12–20)
  相似文献   
88.
Implantable neural electrodes must drastically improve chronic recording stability before they can be translated into long-term human clinical prosthetics. Previous studies suggest that sub-cellular sized and mechanically compliant probes may result in improved tissue integration and recording longevity. However, currently these design features are restricted by the opposing mechanical requirements needed for minimally damaging insertions. We designed a non-cytotoxic, carboxymethylcellulose (CMC) based dissolvable delivery vehicle (shuttle) to provide the mechanical support for insertion of ultra-small, ultra-compliant microfabricated neural probes. Stiff CMC-based shuttles rapidly soften immediately after being placed ∼1 mm above an open craniotomy as they absorb vapors from the brain. To address this, we developed a sophisticated targeting, high speed insertion (∼80 mm/s), and release system to implant these shuttles. After implantation, the goal is for the shuttle to dissolve away leaving only the electrodes behind. Here we show the histology of chronically implanted shuttles of large (300 μm × 125 μm) and small (100 μm × 125 μm) size at discrete time points over 12 weeks. Early time points show the CMC shuttle expanded after insertion as it absorbed moisture from the brain and slowly dissolved. At later time points neuronal cell bodies populate regions within the original shuttle tract. The large CMC shuttles show that the CMC expansion can cause extended secondary damage. On the other hand, the smaller CMC shuttles show limited secondary damage, wound closure by 4 weeks, absence of activated microglia at 12 weeks, as well as evidence suggesting neural regeneration at the implant site. This shuttle, therefore, shows great promise facilitating the implantation of nontraditional ultra-small, and ultra-compliant probes.  相似文献   
89.

Objective

This study aimed to investigate whether the supplementation of Verbal Fluency: Animal category test (VF) performance can improve the screening ability of Mini-Mental State Examination (MMSE) for mild cognitive impairment (MCI), dementia and their major subtypes.

Methods

Six hundred fifty-five cognitively normal (CN), 366 MCI [282 amnestic MCI (aMCI); 84 non-amnestic MCI (naMCI)] and 494 dementia [346 Alzheimer''s disease (AD); and 148 non-Alzheimer''s disease dementia (NAD)] individuals living in the community were included (all aged 50 years and older) in the study.

Results

The VF-supplemented MMSE (MMSE+VF) score had a significantly better screening ability for MCI, dementia and overall cognitive impairment (MCI plus dementia) than the MMSE raw score alone. MMSE+VF showed a significantly better ability than MMSE for both MCI subtypes, i.e., aMCI and naMCI. In the case of dementia subtypes, MMSE+VF was better than the MMSE alone for NAD screening, but not for AD screening.

Conclusion

The results support the usefulness of VF-supplementation to improve the screening performance of MMSE for MCI and NAD.  相似文献   
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