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941.
Research over the past 25 years and the use of accelerator mass spectrometry (AMS) have demonstrated benefits of single‐atom counting of 14C compared with scintillation monitoring of 14C radioactive decay for a multitude of applications in drug development studies. These include pharmacokinetics and metabolism studies, microdosing studies, and quantification of DNA adducts. In the last decade, the possibility of single‐atom counting using lasers has been demonstrated, providing the possibility of simplified laboratory‐based systems, which can equal or excel AMS sensitivity and provide scintillation system convenience without high levels of radioactivity. To achieve the required sensitivity, optical storage cavities have been used to enhance the laser interaction of the low densities of radiocarbon present. Two types of laser technologies have been used‐cavity ring‐down spectroscopy (CRDS) and intracavity opto‐galvanic spectroscopy (ICOGS). Problems to be overcome to achieve routine use have included separation of the 14C signal from backgrounds, achievement of acceptable precision and accuracy, reduction of measurement times for small samples, and improvement in the ease of use for the operator. Both technologies have achieved impressive results to date using samples of order 1 mg with CRDS and 10 μg with ICOGS. Commercial development is the next step.  相似文献   
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总结分析1例开放性胫腓骨骨折合并胫后静脉离断,胫后动脉损伤(GustiloⅢC型)并发骨筋膜室综合征患者的护理经验。其护理要点包括:严重创伤后病情观察与预防失血性休克,平稳过渡到手术;骨筋膜室综合征的应急处理;大面积皮肤缺损多次清创及VSD引流的护理及创面管理;胫跖牵引技术创新在足下垂护理中的运用;通过健肢、术肢及生活自理能力训练,使患者功能最大程度恢复。  相似文献   
943.
BACKGROUNDSudden hearing loss (SHL) is associated with serious systematic conditions such as neoplasms, vascular events, autoimmune diseases, infections, and iatrogenic injury. Some authors report that SHL can be an early warning sign of impending vertebrobasilar ischemic stroke. It is important to distinguish stroke from benign disease. CASE SUMMARYA 48-year-old male patient presented with SHL and vertigo as first symptoms. Diffusion-weighted imaging revealed high signal intensity in the left posterior inferior cerebellar artery territory of the cerebellar hemisphere and high signal intensity in the right pons and bridge cerebellar arm, confirming that the patient had cerebral infarction. Treatment with antiplatelet drugs, steroid anti-inflammatory drugs, and neurotrophic nerve therapy promoted blood circulation and removed blood stasis, and the symptoms of the patient were significantly improved. CONCLUSIONSHL and vertigo could be the initial symptoms of vertebrobasilar ischemic stroke.  相似文献   
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Peters’ anomaly accounts for the highest type of Anterior Segment Dysgenesis (ASD). The main features of Peters’ anomaly are: congenital corneal opacity centrally, defect in the posterior stroma and absence of Descemet’s membrane and the endothelium. However, this condition has wide clinical and histopathological variations in appearance, associations and severity. In this case series, we summarize 6 corneas in 5 Saudi cases of Peters’ anomaly (and describe 2 in detail) with unique histopathological findings that are additional to the typical known ones, shedding some light on the nomenclature of these variants according to the reported cases in the English-written literature. This will widen the spectrum of findings known to ophthalmic pathologists and ophthalmologists about this anomaly. This is also of importance in the assessment of the congenital glaucoma cases commonly seen in Saudi Arabia that often happens in association with ASD.  相似文献   
946.

Purpose

To identify anatomical aberrations following PSARP procedure by using MRI, while correlating MRI findings to clinical outcome.

Patients and methods

Between January 2014 and December 2017, we conducted our study on male patients with rectourethral fistula who underwent PSARP. Postoperative pelvic MRI studies were performed and correlated to their clinical continence scores (Rintala, and Krickenbeck classification).

Results

The study included 31 patients. Fourteen patients were retrieved from the hospital records and accepted to participate in the study; while the remaining 17 were collected from the fecal incontinence clinic. Their age ranged from 40 to 156?months (mean 83) We divided patients in the study into two groups according to their Rintala continence scores: (Group A) 15 patients with low scores (10 or less); and (Group B) 16 patients with higher scores (more than 10). We detected wider pelvic hiatus (hiatus/PC ratio) and more obtuse anorectal angle in group A than B.

Conclusion

Several anatomical alterations can be detected by MRI following the PSARP procedure that include abnormalities in the striated muscle sphincter (attenuation/deficiency), deviated neorectum, and presence of excessive perirectal fat. A widened pelvic hiatus and/or obtuse anorectal angle may correlate with poor fecal continence in these patients.

Level of Evidence

This is a case control study (level III evidence).  相似文献   
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Measuring clinicians' shared decision‐making (SDM) performance is a key requirement given the intensity of policy interest in many developed countries – yet it remains one of the most difficult methodological challenges, which is a concern for many stakeholders. In this Viewpoint Article, we investigate the development of existing patient‐reported measures (PRMs) of SDM identified in a recent review. We find that patients were involved in the development of only four of the 13 measures. This lack of patient involvement in PRM development is associated with two major threats to content validity, common to all 13 PRMs of SDM: (i) an assumption of patient awareness of ‘decision points’ and (ii) an assumption that there is only one decision point in each healthcare consultation. We provide detailed examples of these threats and their impact on accurate assessment of SDM processes and outcomes, which may hamper efforts to introduce incentives for SDM implementation. We propose cognitive interviewing as a recommended method of involving patients in the design of PRMs in the field of SDM and provide a practical example of this approach.  相似文献   
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