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排序方式: 共有615条查询结果,搜索用时 6 毫秒
611.
Wenner J Johansson J Johnsson F Oberg S 《The American journal of gastroenterology》2007,102(9):1862-1869
BACKGROUND: The discriminative power of 48-h wireless esophageal pH monitoring in the diagnosis of gastroesophageal reflux disease has not been clearly demonstrated, and the cutoff level for esophageal acid exposure generating the optimal sensitivity and specificity is unknown. SUBJECTS AND Patients with typical reflux symptoms and a distinct response to acid suppressive medication METHODS: underwent upper GI endoscopy followed by 48-h wireless esophageal pH studies with the pH electrode placed 6 cm above the squamocolumnar junction. The results were compared to those obtained in 55 healthy controls. Sensitivity, specificity, and thresholds for esophageal acid exposure were analyzed using receiver operating characteristic (ROC) curves. RESULTS: The patient population consisted of 64 patients, 25 women and 39 men, with a median age of 48 yr.Analysis of the area under the ROC curve showed that, for all patients as well as for subgroups of patients with (N = 33) and without (N = 31) esophagitis, the total percent time with pH <4 for the 48-h study period was the best parameter to discriminate patients from controls. Analysis of acid exposure for day 1, day 2, or using the day with the highest acid exposure did not improve the diagnostic accuracy. A test specificity in the range of 90-95% resulted in a cutoff level of 3.6-4.4% of the total time with pH <4 for the 48-h period. This threshold generated a test sensitivity of 59-64% in all patients, 76-79% for patients with esophagitis and 42-48% in patients with no esophagitis. CONCLUSIONS: The total percentage of time that esophageal pH was less than 4 for the entire 48-h study period was the parameter that best discriminated patients with typical reflux symptoms from healthy controls, and to achieve a specificity of 90-95% a cutoff level of 4% is recommended. The low sensitivity of wireless pH recording in patients without erosive esophagitis substantially reduces the clinical value of the test. 相似文献
612.
Berg K Narazaki K Latin R Vincent W Meisinger M Sjoberg C Kaufman C 《The Journal of sports medicine and physical fitness》2007,47(4):395-400
AIM: Many sports are played intermittently in bursts of high, moderate, and low intensity activity. The pattern of exercise intensity has been assessed from heart rate (HR) and time motion analysis and few data are available based on assessment of exercise intensity by means of direct measurement of oxygen uptake. The aim of this study was to directly assess oxygen uptake (VO(2)) using a portable metabolic measuring device to describe the aerobic demand and to determine the associated energy expenditure (EE). METHODS: Fourteen recreational racquetball players (3 females and 11 males; mean age, height, and mass of 23.1+/-2.8 years, 178.1+/-7.1 cm, and 81.1+/-19.6 kg, respectively) played for 40 min while wearing a portable metabolic system to assess VO(2) and a Polar watch to measure HR. Rating of perceived exertion (RPE) (Borg 6-20 scale) was assessed at 5 min intervals during breaks in play. RESULTS: The mean VO(2), HR, and RPE over 40 min of play were 27.3+/-1.8 mL/kg/min, 155.3+/-2.8 bpm, and 12.9+/-0.6, respectively. The associated EE was a total of 1 844 kj (440 kcal) or 465 kj/min (11.1 kcal/min). These data were examined across 13.3 min time periods of play, in order to determine if they changed during play because of fatigue. VO(2) decreased significantly (P<0.05), while HR increased (P<0.05). RPE rose across periods of play, but not significantly. CONCLUSION: Recreational racquetball appears to elicit a VO(2) that would allow aerobic conditioning in many persons. It does so with an RPE that is nearly 'somewhat hard'. 相似文献
613.
Samuelsson A Abdiu A Wackenfors A Sjöberg F 《Burns : journal of the International Society for Burn Injuries》2008,34(5):617-622
OBJECTIVES: To investigate serotonin (5HT) locally in burned and uninjured skin (intracutaneous) by microdialysis, and simultaneously record urinary and blood values in the same subjects. For comparison, serotonin values were also measured in skin of healthy controls. DESIGN AND SETTING: An experimental study in burned patients with of more than 25% TBSA (total burn surface area) % in an 8-bed tertiary burns unit, serving about 3.5 million persons. PATIENTS AND METHODS: Six subjects with a median TBSA% of 59% (range 33.5-90), and five healthy controls were examined by intracutaneous microdialysis of the skin. RESULTS: 5HT was increased in burned patients, compared with controls. This increase was tenfold in skin and was noted both in uninjured and burned skin. The highest values were recorded on day 1 (median 16.1nmol in uninjured and 9.5nmol in burned skin) and day 2 (15.6nmol in uninjured and 13.4nmol in burned skin). A rapid reduction was noted on day 3 (4.9nmol in uninjured and 3.8nmol in burned skin). The corresponding value for control subjects was 1.3nmol. The 5HT in blood was twice normal on day 2, and gradually reduced on days 3 and 4 (3189, 3035 and 2573nmol, respectively). Urinary 5HT concentrations were increased only on day 2 at 1755nmol and thereafter returned to the normal range on days 3 and 4 (1248 and 1344nmol, respectively). CONCLUSIONS: We showed that microdialysis may be used in the critical care of burns, and local skin serotonin concentrations examined continuously for several days. The findings of significantly raised tissue serotonin concentrations, compared to that in blood and urine, suggests that serotonin may be important in local vascular control and formation of oedema. 相似文献
614.
OBJECTIVE: To investigate the relationship between ASAT, CKMB, troponin-T and mortality after cardiac surgery. DESIGN: ASAT, CKMB and TnT were analysed in 116 patients. Correlation, sensitivity, specificity and predictive values for permanent myocardial injury (defined as TnT > or = 2.0 microg/l postoperative day four) were calculated. In the second part our clinical protocol (ASAT on postoperative day 1 and TnT on day 3-4 in patients with ASAT above 2.5 microkat/l) was evaluated. Mortality was compared between patients with ASAT < 2.5 microkat/l (ASAT-), 2. ASAT > or = 2.5 microkat/l and TnT < 2.0 microg/l (ASAT+/TnT-) and 3. ASAT > or = 2.5 microkat/l and TnT > or = 2.0 microg/l (ASAT+/TnT+). RESULTS: Both ASAT and CKMB had irrespectively of cut-off level, low positive and high negative predictive value of permanent myocardial injury. Early and mid-term mortality did not differ significantly between ASAT- and ASAT+/TnT- patients. CONCLUSIONS: ASAT and CKMB can be used to exclude but not to diagnose permanent myocardial injury after cardiac surgery. Increased postoperative ASAT in the absence of increased TnT is not associated with worse clinical outcome than after normal postoperative ASAT. 相似文献
615.
Thomas List Thomas Lundeberg Inger Lundström Folke Lindström Nils Ravald 《Acta odontologica Scandinavica》2013,71(2):95-99
Twenty-one patients, 20 women and 1 man, participated in a controlled study. All patients were diagnosed with primary Sjögren's syndrome (1°SS) according to the Copenhagen and San Diego criteria. The patients were randomly assigned to either a group receiving acupuncture treatment or a control group with no active treatment. The patients in the control group received acupuncture after 10 weeks when the acupuncture treatment was completed in the first group. A majority of the patients subjectively reported some improvement after treatment, and a significant increase in paraffin-stimulated saliva secretion was found after treatment. No statistically significant differences between the acupuncture group and the control group were seen in unstimulated salivary secretion or most of the subjective variables. The study showed that acupuncture is of limited value for patients with 1°SS. 相似文献