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We present two patients with angulated, proximal left circumflex lesions, one a chronic total occlusion and one an acute subtotal occlusion. In both cases, use of the deflectable tip Venture Catheter (Velocimed, Minneapolis, MN) facilitated guide wire passage and successful percutaneous coronary intervention (PCI) after prior attempts at guide wire passage with standard wires were unsuccessful.  相似文献   
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Conventional follicle harvesting techniques for hair transplantation are limited by the available scalp donor hair. The development of an innovative technique of microsurgical single follicular unit extraction has made it possible to exploit body hair grafts for scalp transplantation. This case study reports on 18 months of follow-up on a patient with extensive scalp scarring who underwent a transplantation procedure using donor chest hair. The photographically documented results show a change in the length of the chest hair measuring an average of 4 cm at transplant to 15 cm by 18 months post-transplant. The transplanted chest grafts provided an excellent cosmetic result for hair replacement.  相似文献   
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Background: Magnetic resonance neurography (MRN) is an imaging method by which nerves can be selectively highlighted. Using commercial software, the authors explored a variety of approaches to develop a three-dimensional volume-rendered MRN image of the entire brachial plexus and used it to evaluate the accuracy of infraclavicular block approaches.

Methods: With institutional review board approval, MRN of the brachial plexus was performed in 10 volunteer subjects. MRN imaging was performed on a GE 1.5-tesla magnetic resonance scanner (General Electric Healthcare Technologies, Waukesha, WI) using a phased array torso coil. Coronal STIR and T1 oblique sagittal sequences of the brachial plexus were obtained. Multiple software programs were explored for enhanced display and manipulation of the composite magnetic resonance images. The authors developed a frontal slab composite approach that allows single-frame reconstruction of a three-dimensional volume-rendered image of the entire brachial plexus. Automatic segmentation was supplemented by manual segmentation in nearly all cases. For each of three infraclavicular approaches (posteriorly directed needle below midclavicle, infracoracoid, or caudomedial to coracoid), the targeting error was measured as the distance from the MRN plexus midpoint to the approach-targeted site.

Results: Composite frontal slabs (coronal views), which are single-frame three-dimensional volume renderings from image-enhanced two-dimensional frontal view projections of the underlying coronal slices, were created. The targeting errors (mean +/- SD) for the approaches-midclavicle, infracoracoid, caudomedial to coracoid-were 0.43 +/- 0.67, 0.99 +/- 1.22, and 0.65 +/- 1.14 cm, respectively.  相似文献   

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PURPOSE: This investigation examined the effects of nebulized hypertonic saline, isotonic saline (IS), and sterile (hypotonic) water on phonation threshold pressure (PTP) and self-perceived phonatory effort (PPE) following a surface laryngeal dehydration challenge. METHOD: In a double-blind, randomized experimental trial, 60 vocally healthy women (n = 15 per group) underwent a laryngeal desiccation challenge involving oral breathing for 15 min using medical-grade dry air (RH<1%). Three of the four groups then received nebulized isotonic saline (0.9% NaCl), hypertonic saline (7% NaCl), or sterile (hypotonic) water, respectively; the 4th group served as a nontreatment control. PTP and PPE were estimated for high-pitched productions at baseline, immediately postdesiccation, and at 5, 20, 35, and 50 min postnebulization. RESULTS: PTP increased significantly for all groups following the desiccation challenge. PTP values were, on average, 0.5 cm H(2)O greater immediately postdesiccation versus baseline. In contrast, PTP values did not change significantly following the administration of nebulized treatments, although a temporary trend toward a reduction in PTP was observed for the IS group. Unexpectedly, PPE ratings decreased significantly after the desiccation challenge. In general, PPE ratings were poorly correlated with PTP measures. CONCLUSION: A laryngeal desiccation challenge (i.e., temporary exposure to extremely low relative humidity while breathing transorally) significantly increased PTP. Although interesting trends emerged, none of the nebulized treatments significantly enhanced recovery from the negative effects of desiccation on PTP. In light of very low correlations between PTP and PPE, serious questions are raised regarding presumed associations between these measures.  相似文献   
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Decline in episodic memory, the encoding and retrieval of autobiographical events, is a hallmark of normal cognitive aging. Although the primary causes of this decline remain elusive, event-related brain potential (ERP) studies have contributed to an understanding of age-related episodic memory failure. These data reveal that, although the retrieval-based episodic memory (EM) effect does not differ dramatically between young and older adults, the acquisition-related data suggest a decline in episodic encoding (i.e., semantic elaboration) with increasing age. We conclude that, at the current state of knowledge, encoding deficiencies are more important than retrieval deficits in understanding the causes of episodic memory decline in the older adult.  相似文献   
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