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991.
The purpose of this investigation was to describe the just noticeable difference (JND) in perceived exertion during cycle exercise. Males (n = 20) and females (n = 26) (21.4 ± 3.1 year) performed load-incremented cycle exercise to peak intensity. At the end of each minute, subjects rated their overall-body perceived exertion using the OMNI (0–10) rating of perceived exertion (RPE) scale. Individual regression derived the power output (PO) corresponding to RPE 5. This PO served as the standard stimulus (SS). On a separate occasion, four 5-min cycling bouts were performed with 5 min rest between bouts. During bouts 1 and 3 subjects cycled at the SS. During bouts 2 and 4 subjects adjusted the resistance to achieve a level of exertion just noticeably above/below the SS. The difference in final 30-s oxygen consumption (VO2) and PO between each JND bout and the previous SS were the above (JND-A) and below (JND-B) perceived exertion JNDs. JND-A and JND-B were compared between genders and between subjects exhibiting lower versus higher ventilatory threshold (VT) and VO2PEAK within genders for VO2 (l·min?1, %VO2PEAK) and PO (W, %SS). JND-B was significantly (P < 0.05) greater than JND-A for VO2 and PO, when expressed in absolute (l·min?1, W) and relative units (%VO2PEAK, %SS). Males exhibited greater JND values than females in absolute, but not relative, units. Subjects with lower and higher VT and VO2PEAK exhibited similar JND values. The JND can serve as an effective tool to measure perceptual acuity and to determine individual ability to self-regulate prescribed exercise intensities.  相似文献   
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993.

Background

Several well-established tumour prognostic factors are used to guide the clinical management of patients with breast cancer. Lymphovascular invasion and angiogenesis have also been reported to have some promise as prognostic factors. The aim of the present study was to examine the prognostic value of tumour lymphovascular invasion and microvessel density compared with that of established prognostic factors in invasive ductal breast cancer.

Methods

In addition to hormone receptor status and Ki-67 proliferative activity, lymphovascular invasion and microvessel density and their relationship with survival were examined in patients with invasive ductal breast cancer. Full sections and tissue microarrays (n?=?384 patients) were utilised to assess these factors and were scored by appropriate methods.

Results

On univariate analysis tumour size (P?<?0.05), lymph node involvement (P?<?0.01), lymphovascular invasion (P?<?0.05), microvessel density (P?<?0.05) and local- regional treatment (P?<?0.01) were associated with poorer survival in ER negative tumours. On multivariate analysis in ER negative tumours lymph node involvement (P?<?0.01) and local- regional treatment (P?<?0.05) were independently associated with poorer cancer-specific survival. On univariate analysis tumour grade (P?<?0.05), lymph node involvement (P?<?0.001), HER-2 (P?<?0.05), Ki-67 (P?<?0.01) and lymphovascular invasion (P?<?0.001) were associated with poorer survival in ER positive tumours. On multivariate analysis lymph node involvement (P?<?0.001), Ki-67 (P?<?0.001) and lymphovascular invasion (P?<?0.05) were independently associated with poorer cancer-specific survival in ER positive tumours.

Conclusion

Lymphovascular invasion but not microvessel density was independently associated with poorer survival in patients with ER positive but not ER negative invasive ductal breast cancer.
  相似文献   
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BackgroundThe Johns Hopkins Highest Level of Mobility (JH-HLM) scale is used to document the observed mobility of hospitalized patients, including those patients in the intensive care unit (ICU) setting.ObjectiveTo evaluate the inter-rater reliability of the JH-HLM, completed by physical therapists, across medical, surgical, and neurological adult ICUs at a single large academic hospital.MethodsThe JH-HLM is an ordinal scale for documenting a patient’s highest observed level of activity, ranging from lying in bed (score = 1) to ambulating >250 feet (score = 8). Eighty-one rehabilitation sessions were conducted by eight physical therapists, with 1 of 2 reference physical therapist rater simultaneously observing the session and independently scoring the JH-HLM. The intraclass correlation coefficient was used to determine the inter-rater reliability.ResultsA total of 77 (95%) of 81 assessments had perfect agreement. The overall intraclass correlation coefficient for inter-rater reliability was 0.98 (95% confidence interval: 0.96, 0.99), with similar scores in the medical, surgical, and neurological ICUs. A Bland–Altman plot revealed a mean difference in JH-HLM scoring of 0 (limits of agreement: ?0.54 to 0.61).ConclusionThe JH-HLM has excellent inter-rater reliability as part of routine physical therapy practice, across different types of adult ICUs.  相似文献   
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1000.
Lymphedema is a chronic progressive edematous disease that in the United States is most commonly related to malignancy and its treatment. Lymphaticovenular anastomosis is a recently introduced microsurgical treatment option for lymphedema that requires the identification and mapping of individual lymphatic channels. While nuclear medicine lymphoscintigraphy has been the primary imaging modality performed to evaluate suspected lymphedema, lymphoscintigraphy does not provide the spatial information necessary for presurgical planning. High‐resolution dynamic 3D magnetic resonance imaging (MRI) can noninvasively image abnormal lymphatic channels to both diagnose lymphedema and depict the location and number of individual lymphatic channels for surgical planning. MR lymphangiography can be performed at 1.5T or 3.0T using multichannel phased array surface coils. The main components of the exam are a heavily T2‐weighted 3D sequence to define the severity and extent of edema, a high‐resolution dynamic 3D gradient echo imaging after intracutaneous contrast injection to visualize lymphatic channels, and a delayed 3D gradient echo sequence after intravenous contrast to define veins. This article reviews the pathophysiology and microsurgical treatment of lymphedema, presents the imaging protocol used at our institution, and describes exam interpretation and the image postprocessing performed for surgical planning. J. MAGN. RESON. IMAGING 2015;42:1465–1477.  相似文献   
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