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31.
Five healthy fasting male subjects were each given single doses of intravenous ampicillin (471 mg), oral ampicillin tablets (495 mg), oral bacampicillin hydrochloride tablets (562 mg ampicillin equivalent), and oral pivampicillin hydrochloride capsules (491 mg ampicillin equivalent) in a crossover experiment. The resulting concentrations of ampicillin were determined in plasma and urine. The pharmacokinetic analysis was made according to a two-compartment open model. The total distribution volume of unbound ampicillin during the disposition phase was 0.247 ± 0.045 (sd) liter/kg, which is only slightly more than the extracellular fluid, suggesting that tissue binding and intracellular distribution of ampicillin are limited. The bioavailability of the esters bacampicillin (86 ± 11%) and pivampicillin (92± 18%) was significantly greater than that of ampicillin (62 ± 17%); however, the difference between the esters was not statistically significant. The absorption for all drugs given orally proceeded at a constant rate, suggesting zero-order release rates from the products. The absorption rate was highest for bacampicillin (0.89 ± 0.39% of dose absorbed per minute), followed by pivampicillin (0.64 ± 0.19) and ampicillin (0.58 ± 0.16). Bacampicillin also had the shortest lag time for the start of absorption (7.0 ± 0.9 min) under the present conditions. Thus, in comparison with ampicillin, the esters have a higher bioavailability, which, in fact, is close to the theoretically highest possible value by clearance concepts. The higher bioavailability in connection with higher absorption rates may be clinically important in ampicillin treatment by the oral route.This work was supported by the Swedish Medical Research Council, Project No. 522 (L. O. B.).  相似文献   
32.
33.
OBJECTIVE: To investigate gene expressions for neurohypophyseal and ovarian hormones as well as their receptors in the endometrium of women with primary dysmenorrhoea and healthy subjects at ovulation. STUDY DESIGN: A group of eight women with moderate to severe dysmenorrhoea and eight healthy subjects were compared in parallel between 18 and 35 years of age, regularly menstruating, non-overweight and nulliparous. The study was performed at The Department of Obstetrics and Gynecology, University Hospital of Lund, Sweden. Endometrial biopsies were taken around the time of ovulation, which was determined by repeated ultrasound examinations. Receptor and gene expressions for oxytocin and vasopressin in the tissue were measured. RESULTS: The gene expression for oxytocin receptor was significantly lower in dysmenorrhoic than in healthy women, in median 1.21 and 3.44 oxytocin-receptor/actin, respectively (p=0.048). The expressions for oxytocin peptide, vasopressin V1a receptor, oestrogen receptor alpha, beta and progesterone receptor did not differ between the two groups. Expression of vasopressin peptide was not detectable. CONCLUSION: A lower oxytocin receptor gene expression at mid-cycle could be involved in the aetiology of primary dysmenorrhoea. However, the importance of a paracrine effect of oxytocin and its receptor at ovulation warrants further investigation.  相似文献   
34.
We report a case of intrauterine fetal death at term with a possible association to an oral bacterium, Rothia dentocariosa. A healthy primiparous woman was admitted at term with an intrauterine fetal death after an uncomplicated pregnancy. R. dentocariosa was found in the fetal blood culture.  相似文献   
35.
Hypovitaminosis D is prevalent worldwide, and especially in South-Asia. According to the Institute of Medicine (IOM), 25(OH)D levels below 30 nmol/L are defined as vitamin D deficiency (VDD) and levels between 30–50 nmol/L as insufficiency (VDI). Besides its role in calcium homeostasis, it has been postulated that vitamin D is involved in metabolic syndrome. Given the scarcity of data on vitamin D status in Nepal, we aimed to examine the prevalence of VDD and VDI, as well as the determinants and association with metabolic parameters (lipids, HbA1c), in a cohort of women in rural Nepal. Altogether, 733 women 48.5 ± 11.7 years of age were included. VDD and VDI were observed in 6.3 and 42.4% of the participants, respectively, and the prevalence increased by age. Women reporting intake of milk and eggs > 2 times weekly had higher 25(OH)D levels than those reporting intake < 2 times weekly. Women with vitamin D levels < 50 nmol/L displayed higher levels of cholesterol, LDL-cholesterol, triglycerides, and HbA1c. Additionally, a regression analysis showed a significant association between hypovitaminosis D, dyslipidemia, and HbA1c elevation. In conclusion, VDI was prevalent and increased with age. Milk and egg intake > 2 times weekly seemed to decrease the risk of VDI. Moreover, hypovitaminosis D was associated with an adverse metabolic profile.  相似文献   
36.
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   

37.

Background

To our knowledge this is the first published estimate of the charges of the care of burns in Sweden. The Linköping Burn Interventional Score has been used to calculate the charges for each burned patient since 1993. The treatment of burns is versatile, and depends on the depth and extension of the burn. This requires a flexible system to detect the actual differences in the care provided. We aimed to describe the model of burn care that we used to calculate the charges incurred during the acute phase until discharge, so it could be reproduced and applied in other burn centres, which would facilitate a future objective comparison of the expenses in burn care.

Methods

All patients admitted with burns during the period 2010–15 were included. We analysed clinical and economic data from the daily burn scores during the acute phase of the burn until discharge from the burn centre.

Results

Total median charge/patient was US$ 28 199 (10th–90th centiles 4668-197 781) for 696 patients admitted. Burns caused by hot objects and electricity resulted in the highest charges/TBSA%, while charges/day were similar for the different causes of injury. Flame burns resulted in the highest mean charges/admission, probably because they had the longest duration of stay. Mean charges/patient increased in a linear fashion among the different age groups.

Conclusion

Our intervention-based estimate of charges has proved to be a valid tool that is sensitive to the procedures that drive the costs of the care of burns such as large TBSA%, intensive care, and operations. The burn score system could be reproduced easily in other burn centres worldwide and facilitate the comparison regardless of the differences in the currency and the economic circumstances.  相似文献   
38.
This study aimed to characterize the ST-recovery loop and assess which range of heart rates (HRs) best discriminates between patients with and without significant coronary artery stenosis. Bicycle exercise tests were undertaken in 44 men and 18 women with coronary artery disease (CAD) and in 59 controls (26 men, 33 women) in the same age range with no signs of CAD. The ST level and the ST-segment slope were continuously monitored, and changes from rest to peak exercise and to 4 min after exercise, respectively, were calculated. Plotting the ST level against HR gives the STHR loop, characterized by the normalized area (NA(alpha)) circumscribed by the ST level during and after exercise from alpha% to 100% of the HR range. Eight values of alpha between 20% and 90% were investigated, and chest and extremity leads were investigated separately. Optimal alpha was found to be < or =70% in men and < or =30% in women. Change in ST-segment slope was the only parameter that gave significant additional discriminating power in both men and women once the area had been taken into account. We conclude that NA(alpha) for extremity and chest leads have similar weights, and that a substantial part of the STHR loop should be taken into consideration, especially in women. NA(30) was superior to end-exercise ST-depression and STHR loop orientation (as defined by the sign of NA(90)) in both men and women, and to ST/HR index in men, in identifying CAD.  相似文献   
39.
Natriuretic peptides in unstable coronary artery disease.   总被引:1,自引:0,他引:1  
Patients with unstable coronary artery disease (CAD), i.e., unstable angina or non-ST-elevation myocardial infarction, vary widely in clinical presentation, prognosis and response to treatment. To select appropriate therapy, early risk stratification has become increasingly important. This review focuses on the emerging role of natriuretic peptides in the early assessment of patients with unstable CAD. We conclude that levels of brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) are strongly associated to mortality and the risk of future congestive heart failure, and carry important prognostic information independent from previously known risk factors in unstable CAD. There are some data indicating that these markers can also be helpful in the selection of appropriate therapy in these patients but further studies are needed. Before a routine use of BNP or NT-proBNP in unstable CAD can be recommended, the cost-effectiveness of adding these new markers to the currently routine markers and their impact on selection of treatment needs further evaluation.  相似文献   
40.
OBJECTIVE: The objective of this article is to investigate predictors of public home help utilization, particularly mental health problems such as dementia and depressive symptoms. METHODS: A population-based sample of community-dwelling people aged 81-100 was interviewed and assessed with medical examinations (N = 502). RESULTS: Dementia increased the odds of receiving public home help among people residing alone. Among coresiding people, it increased the odds of receiving home help, but only among those who had extra residential care. Depressive symptoms decreased the odds of receiving home help among people with lower levels of education who lived alone. Depressive symptoms among highly educated people who lived alone and among coresiding people of any educational level were not related to receipt of home help. DISCUSSION: Improvement of screening activities for public home help needs of community-dwelling elders might allow better targeting of limited social resources to the most needy.  相似文献   
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