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81.
王永  唐鹏飞  张晓梅  吕伟 《临床肺科杂志》2012,17(11):1969-1971
目的 探讨电子支气管镜(EBS)在肺不张诊断中的作用.方法对经EBS确诊的105例肺不张患者进行分析总结.结果 肺不张病因以肺癌最常见,其次是炎症、结核;上肺肺不张以肺癌及结核多见,下肺肺不张以炎症居多;青年组以炎症最多见,中年组及老年组以肺癌较多;肺癌患者镜下表现以管腔新生物多见,炎症以管腔狭窄、充血水肿多见,结核以管壁浸润及管腔狭窄、充血水肿多见.结论 EBS检查在肺不张患者病因诊断中具有重要意义,为肺不张确定病因,明确诊断提供了重要的依据.  相似文献   
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Medical devices have been targets of hacking for over a decade, and this cybersecurity issue has affected many types of medical devices. Lately, the potential for hacking of cardiac devices (pacemakers and defibrillators) claimed the attention of the media, patients, and health care providers. This is a burgeoning problem that our newly electronically connected world faces. In this paper from the Electrophysiology Section Council, we briefly discuss various aspects of this relatively new threat in light of recent incidents involving the potential for hacking of cardiac devices. We explore the possible risks for the patients and the effect of device reconfiguration in an attempt to thwart cybersecurity threats. We provide an outline of what can be done to improve cybersecurity from the standpoint of the manufacturer, government, professional societies, physician, and patient.  相似文献   
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Teeth adopt a variety of different morphologies, each of which is presumably optimized for performing specific functions during feeding. It is generally agreed that the enamel cap is a crucial element in controlling the mechanical behavior of mammalian teeth under load. Incisors are particularly interesting in terms of structure–function relations, as their role in feeding is that of the ‘first bite’. However, little is known how incisor cap morphology is related to tooth deformation. In the present paper we examine the mechanical behavior of mandibular central incisors in the cercopithecine primate Macaca mulatta under loads similar to those encountered during ingestion. We map three‐dimensional displacements on the labial surface of the crown as it is compressed, using electronic speckle pattern interferometry (ESPI), an optical metrology method. In addition, micro‐computed tomography is used to obtain data regarding the morphology of the enamel cap, which in the M. mulatta lower incisors exhibits missing or very little enamel on the lingual face. The results showed that although compressed along a longitudinal axis, deformation in the incisors mostly occurred in the lingual direction and orthogonal to the direction of the applied load. Both isolated, embedded teeth and teeth in the mandible showed considerable lingual deformation. Incisor deformation in the mandible was generally greater, reflecting the additional freedom of movement enabled by the supporting structures. We show that the association with adjacent teeth in the arch is significant for the behavior of the tooth under load. Finally, loading two teeth simultaneously in the mandible showed that they work as one functional unit. We suggest that these results demonstrate the importance of enamel cap morphology in directing deformation behavior; an ability stemming from the stiffness of the enamel cap overlying the more pliable dentin.  相似文献   
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Methods to obtain informed consent digitally or electronically may increase the participation of racially and geographically diverse pregnant women in prospective research, which is essential to improve the evidence base for maternity care. We evaluated the feasibility and utility of e-consent in the first year of a multiyear clinical trial involving pregnant women. Of the 86 women screened, 71 were eligible, 65 (93% of eligible) agreed to review the e-consent form, and 61 (86% of eligible) completed the e-consent process. Of the interested women who were sent the e-consent link, all were able to complete the e-consent process, even those who reported low health literacy. Women of all racial and ethnic groups were equally likely to consent, and the sample of women who consented was consistent with practice demographics. E-consent is feasible and easy to use with pregnant women and may expedite enrollment of a representative sample.  相似文献   
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To evaluate the dosimetric impact of respiratory breast motion and daily setup error on whole breast irradiation (WBI) using three irradiation techniques; conventional wedge (CW), field-in-field (FIF) and irregular surface compensator (ISC). WBI was planned for 16 breast cancer patients. The dose indices for evaluated clinical target volume (CTVevl), lung, and body were evaluated. For the anterior-posterior (AP) respiratory motion and setup error of a single fraction, the isocenter was moved according to a sine function, and the dose indices were averaged over one period. Furthermore, the dose indices were weighted according to setup error frequencies that have a normal distribution to model systematic and random setup error for the entire treatment course. In all irradiation techniques, AP movement has a significant impact on dose distribution. CTVevlD95 (the minimum relative dose that covers 95 % volume) and V95 (the relative volume receiving 95 % of the prescribed dose) were observed to significantly decrease from the original ISC plan when simulated for the entire treatment course. In contrast, the D95, V95 and dose homogeneity index did not significantly differ from those of the original plans for FIF and CW. With regard to lung dose, the effect of motion was very similar among all three techniques. The dosimetric impact of AP respiratory breast motion and setup error was largest for the ISC technique, and the second greatest effect was observed with the FIF technique. However, these variations are relatively small.  相似文献   
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An analysis is made of the controversial application of the theory of disproportionate damage in the anaesthetic act, due to the high inherent risk, and regardless of the seriousness and importance of the surgery being performed. The existence of a disproportionate damage, that is, damage not foreseen nor accountable within the framework of the professional performance of the anaesthetist, does not by itself determine the existence of liability on the part of the anaesthetist, but the demand from the professionals themselves for a coherent explanation of the serious disagreement between the initial risk implied by their actions and the final consequence produced.  相似文献   
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