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51.
Summary Felodipine is a vasodilating calcium channel blocker of the dihydropyridine type. The effects of felodipine on post-ischaemic renal function were evaluated in rats subjected to bilateral renal artery occlusion for 30 or 60 min.In a first set of experiments the recovery of renal function after 30 or 60 min of renal artery occlusion was followed intermittently for 16 days by endogenous creatinine clearance. Renal function was better preserved in rats given felodipine (45 nmol/kg i.v.) during the occlusion period than in vehicle-treated control rats. The survival rate after 60-min occlusion was 11% in controls but 70% in the felodipine-treated rats. After occlusion for 30 min the survival rate was similar in the two groups, but renal function recovered faster in the felodipine group than in the controls.In a second series, acute renal damage was evaluated by the extent of erythrocytes trapped in the kidney after 30-min reperfusion following 60-min renal artery occlusion. Felodipine administration (45 nmol/kg) during the occlusion reduced renal damage compared with vehicle controls. Kidney weight and systemic haematocrit were also better maintained in the felodipine-treated rats. Furthermore, renal damage was reduced by the t-butyl analogue or felodipine, H 186/86, which is devoid of vasodilatory effects. The results demonstrate that treatment with the vasodilator calcium channel blocker felodipine protects the kidney from ischaemic/reperfusion injuries. The tissue protection is not related to the haemodynamic effects alone, since the haemodynamically inactive dihydropyridine H 186/86 also reduced the extent of renal damage. An additional antiperoxidant or scavanger-like effect inherent in the dihydropyridine molecule is suggested. Send offprint requests to M. Nordlander at the above address  相似文献   
52.
Blix E  Ohlund LS 《Midwifery》2007,23(1):48-58
OBJECTIVE: To explore what information and knowledge the labour admission test is perceived to provide and what meaning the test carries in the daily work of practising midwives. DESIGN: In-depth interviews transcribed verbatim and analysed using the grounded theory technique. SETTING: Four different labour wards in Norway. PARTICIPANTS: A theoretical sample of 12 practising midwives. FINDINGS: The core category "experiencing contradictions" was identified during the analyses, indicating that the midwives found conflicting interests within themselves, or between themselves and others when using the labour admission test. They experienced contradictions between professional identity and the increasing use of technology, between feeling safe and feeling unsafe and between having power and being powerless. KEY CONCLUSIONS: The labour admission traces could be difficult to interpret, especially for newly qualified midwives. Some midwives thought that a labour admission trace could protect them in case of litigation. The hierarchy of power in the labour ward influences the use and interpretation of the labour admission test. Some midwives felt their professional identity threatened and that midwives in general are losing their traditional skills because of the increasing use of obstetric technology. IMPLICATIONS FOR PRACTICE: The findings of the present study should be taken into consideration when changing practice to not routinely perform the labour admission test. There is also a need for further research on what effect the increasing use of obstetric technology has on traditional midwifery skills.  相似文献   
53.
A questionnaire-based screening tool for male athletes at risk of low energy availability (LEA) could facilitate both research and clinical practice. The present options rely on proxies for LEA such screening tools for disordered eating, exercise dependence, or those validated in female athlete populations. in which the female-specific sections are excluded. To overcome these limitations and support progress in understanding LEA in males, centres in Australia, Norway, Denmark, and Sweden collaborated to develop a screening tool (LEAM-Q) based on clinical investigations of elite and sub-elite male athletes from multiple countries and ethnicities, and a variety of endurance and weight-sensitive sports. A bank of questions was developed from previously validated questionnaires and expert opinion on various clinical markers of LEA in athletic or eating disorder populations, dizziness, thermoregulation, gastrointestinal symptoms, injury, illness, wellbeing, recovery, sleep and sex drive. The validation process covered reliability, content validity, a multivariate analysis of associations between variable responses and clinical markers, and Receiver Operating Characteristics (ROC) curve analysis of variables, with the inclusion threshold being set at 60% sensitivity. Comparison of the scores of the retained questionnaire variables between subjects classified as cases or controls based on clinical markers of LEA revealed an internal consistency and reliability of 0.71. Scores for sleep and thermoregulation were not associated with any clinical marker and were excluded from any further analysis. Of the remaining variables, dizziness, illness, fatigue, and sex drive had sufficient sensitivity to be retained in the questionnaire, but only low sex drive was able to distinguish between LEA cases and controls and was associated with perturbations in key clinical markers and questionnaire responses. In summary, in this large and international cohort, low sex drive was the most effective self-reported symptom in identifying male athletes requiring further clinical assessment for LEA.  相似文献   
54.
Background. Atelectasis is common during and after general anaesthesia. We hypothesized that a ventilation strategy, without recruitment manoeuvres, using a combination of continuous positive airway pressure (CPAP) or positive end-expiratory pressure (PEEP) and a reduced end-expiratory oxygen fraction (FETO2) before ending mask ventilation with CPAP after extubation would reduce the area of postoperative atelectasis.

Methods. Thirty patients were randomized into three groups. During induction and emergence, inspiratory oxygen fractions (FIO2) were 1.0 in the control group and 1.0 or 0.8 in the intervention groups. No CPAP/PEEP was used in the control group, whereas CPAP/PEEP of 6 cmH2O was used in the intervention groups. After extubation, FIO2 was set to 0.30 in the intervention groups and CPAP was applied, aiming at FETO2 < 0.30. Atelectasis was studied by computed tomography 25 min postoperatively.

Results. The median area of atelectasis was 5.2 cm2 (range 1.6–12.2 cm2) and 8.5 cm2 (3–23.1 cm2) in the groups given FIO2 1.0 with or without CPAP/PEEP, respectively. After correction for body mass index the difference between medians (2.9 cm2) was statistically significant (confidence interval 0.2–7.6 cm2, p = 0.04). In the group given FIO2 0.8, in which seven patients were ex- or current smokers, the median area of atelectasis was 8.2 cm2 (1.8–14.7 cm2).

Conclusion. Compared with conventional ventilation, after correction for obesity, this ventilation strategy reduced the area of postoperative atelectasis in one of the intervention groups but not in the other group, which included a higher proportion of smokers.  相似文献   

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Objective

To introduce a novel, simple, utility‐based outcome measure, the number needed per quality‐adjusted life year (QALY) gained (NNQ), and to apply it in clinical practice in anti–tumor necrosis factor (anti‐TNF)–treated patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and spondylarthritis (SpA).

Methods

The NNQ is the number of patients one has to treat in order to gain 1 QALY. It is calculated as the inverted value of the utility gain (area under the curve) over 1 year in a cohort subjected to an intervention. EuroQol Index utility data from the South Swedish Arthritis Treatment register were used.

Results

Patients with RA (n = 1,001), PsA (n = 241), and SpA (n = 255) were eligible for the study. First, second, and third treatment courses were studied. For RA, NNQ was 4.5, 6.4, and 5.2 for first, second, and third courses, respectively. For PsA and SpA, NNQ was 4.2–4.5, irrespective of treatment order. Treatment groups with <50 patients were not analyzed. During the study period 2002–2007, there were no secular trends of utility gains.

Conclusion

The NNQ is an easily derived and understandable utility‐based outcome measure that may be useful for stakeholders and decision makers as well as for clinicians. It was readily applied in this study of TNF blockade across 3 arthritis diagnoses. NNQ varied little over diagnoses and treatment course order, with a possible exception in second treatment course in RA.  相似文献   
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Surgery for fulminating colitis during pregnancy   总被引:2,自引:1,他引:2  
Two cases of fulminating colitis presenting during pregnancy are described. In both cases, resectional surgery was performed. In the first case, cesarean section was combined with subtotal colectomy and ileostomy during the 32nd week of gestation. In the second case, cesarean section was performed during the 33rd week of gestation and proctocolectomy in the puerperium. In both cases, histopathologic examination showed colitis more consistent with Crohn's disease. It is concluded that if fulminating colitis appears during pregnancy it should be treated in the same manner as in the nonpregnant state.  相似文献   
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