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91.
BACKGROUND: Reduced blood flow has been hypothesized to be a major factor in the formation of postradiation fibrosis. This study examined Doppler ultrasonography as a technique to detect changes in blood flow into the tongue during selected lingual gestures, /t/ and /k/. METHODS: Six normal subjects, three young men (mean age, 26 years) and three older men (mean age, 66 years) were examined in an upright position using Doppler ultrasound imaging of the external carotid artery just below the lingual artery. Measurements were made with a standardized segmentation technique before and after three repetitions of four speech production gestures /t/ and /k/, each with natural and maximal force. RESULTS: Blood flow peak systole increased significantly after the speech gestures (p < .001). Pooled before and after gesture values for older subjects were significantly lower than those for younger subjects (p < or = .05). CONCLUSIONS: Ultrasonography is a clinically useful technique for measuring blood flow during a dynamic gesture and may be useful for measuring effects of tumor treatment and in a lingual exercise program.  相似文献   
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BACKGROUND: Head and neck cancer treatment with high-dose chemoradiation may cause xerostomia and affect the patient's perception of swallowing ability. METHOD: Whole saliva production was measured in 36 patients with advanced-stage cancer of the oropharynx before treatment and 3 months after treatment by weighing a 4 x 4 inch gauze before and after a 2-minute chewing period. Presence of multiple eating difficulties was measured by patient interview. Swallowing was examined videofluorographically (VFG). RESULTS: Saliva weight decreased from a mean (SEM) of 5.1 (0.5) g pretreatment to 1.4 (0.5) g after treatment (p<.0001). At 3 months, significantly more patients perceived difficulty swallowing, dry mouth, needing water while eating, food stuck in the mouth or throat, and change in taste. Saliva weight was not correlated with VFG measures of bolus transit or observations of residue. CONCLUSIONS: Chemoradiation treatment results in xerostomia and a significant increase in patient perception of swallowing difficulties. Saliva weight in patients who perceive swallowing problems was lower. Xerostomia did not affect the physiologic aspects of bolus transport. Xerostomia affected the sensory process and comfort of eating more than bolus transport.  相似文献   
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The effect of different pedalling rates (40, 60, 80, 100 and 120 rev min-1) on power generating capability, oxygen uptake (O2) and blood lactate concentration [La]b during incremental tests was studied in seven subjects. No significant differences in O2,max were found (mean +/- S.D., 5.31 +/- 0.13 l min-1). The final external power output delivered to the ergometer during incremental tests (PI,max) was not significantly different when cycling at 60, 80 or 100 rev min-1 (366 +/- 5 W). A significant decrease in PI,max of 60 W was observed at 40 and 120 rev min-1 compared with 60 and 100 rev min-1, respectively (P < 0.01). At 120 rev min-1 there was also a pronounced upward shift of the O2-power output (O2-P) relationship. At 50 W O2 between 80 and 100 rev min-1 amounted to +0.43 l min-1 but to +0.87 l min-1 between 100 and 120 rev min-1. The power output corresponding to 2 and 4 mmol l-1 blood lactate concentration (P[La]2 and P[La]4 ) was also significantly lower (> 50 W) at 120 rev min-1 (P < 0.01) while pedalling at 40, 60, 80 and 100 rev min-1 showed no significant difference. The maximal peak power output (PM, max) during 10 s sprints increased with pedalling rate up to 100 rev min-1. Our study indicates that with increasing pedalling rate the reserves in power generating capability increase, as illustrated by the PI,max/PM,max ratio (54.8, 44.8, 38.1, 34.6, 29.2%), the P[La]4/PM,max ratio (50.4, 38.9, 31.0, 27.7, 22.9%) and the P[La]2/PM,max ratio (42.8, 33.5, 25.6, 23.1, 15.6%) increases. Taking into consideration the O2,max, the PI,max and the reserve in power generating capability we concluded that choosing a high pedalling rate when performing high intensity cycling exercise may be beneficial since it provides greater reserve in power generating capability and this may be advantageous to the muscle in terms of resisting fatigue. However, beyond 100 rev min-1 there is a decrease in external power that can be delivered for an given O2 with an associated earlier onset of metabolic acidosis and clearly this will be disadvantageous for sustained high intensity exercise.  相似文献   
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The nuclear medicine bleeding scan is frequently insufficient to locate sites of bleeding precisely, in spite of its great sensitivity. A small, hand-held Geiger-Müller counter, placed directly on exposed intestine in the operating room, enables precise location of the probable bleeding site. In three patients, the technique allowed a minimal amount of intestine to be resected, distinguished between large- and small-intestinal hemorrhage, and eliminated other foci as sites of bleeding.  相似文献   
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99.

Introduction

Coagulation abnormalities are frequent in sepsis. Conventional coagulation assays, however, have several limitations. A surge of interest exists in the use of point-of-care tests to diagnose hypo- and hypercoagulability in sepsis.We performed a systematic review of available literature to establish the value of rotational thromboelastography (TEG) and thromboelastometry (ROTEM) compared with standard coagulation tests to detect hyper- or hypocoagulability in sepsis patients. Furthermore, we assessed the value of TEG/ROTEM to identify sepsis patients likely to benefit from therapies that interfere with the coagulation system.

Methods

MEDLINE, EMBASE, and the Cochrane Library were searched from 1 January 1980 to 31 December 2012. The search was limited to adults, and language was limited to English. Reference lists of retrieved articles were hand-searched for additional studies. Ongoing trials were searched on http://www.controlled-trials.com and http://www.clinicaltrials.gov. Studies addressing TEG/ROTEM measurements in adult patients with sepsis admitted to the ICU were considered eligible.

Results

Of 680 screened articles, 18 studies were included, of which two were randomized controlled trials, and 16 were observational cohort studies. In patients with sepsis, results show both hyper- and hypocoagulability, as well as TEG/ROTEM values that fell within reference values. Both hyper- and hypocoagulability were to some extent associated with diffuse intravascular coagulation. Compared with conventional coagulation tests, TEG/ROTEM can detect impaired fibrinolysis, which can possibly help to discriminate between sepsis and systemic inflammatory response syndrome (SIRS). A hypocoagulable profile is associated with increased mortality. The value of TEG/ROTEM to identify patients with sepsis who could possibly benefit from therapies interfering with the coagulation system could not be assessed, because studies addressing this topic were limited.

Conclusion

TEG/ROTEM could be a promising tool in diagnosing alterations in coagulation in sepsis. Further research on the value of TEG/ROTEM in these patients is warranted. Given that coagulopathy is a dynamic process, sequential measurements are needed to understand the coagulation patterns in sepsis, as can be detected by TEG/ROTEM.  相似文献   
100.
We report 8 infants with immediate hypersensitivity reactions to foods (milk, egg, or peanut), occurring at the first-known exposure. Each developed symptoms within the first hour, but these generally settled within 2 hours. Sensitisation to the food concerned was demonstrated by positive immediate allergen skin prick tests in every case. Symptoms experienced included irritability, erythematous rash, urticaria, angio-oedema, vomiting, rhinorrhoea, and cough. Five infants were being followed prospectively and 4 were clinically tolerant of the food by age 16 months. The most likely route of sensitisation was via breast milk. None of the infants experienced similar reactions while being breast fed, suggesting that the reaction was dose dependent. As 5 out of a group of 80 infants being followed prospectively developed an immediate reaction at their first known exposure to a food, this appeared to be a not uncommon presentation of food hypersensitivity in infancy.  相似文献   
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