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In a recent issue of Critical Care, Brandt and colleagues report the effects of a 'liberal' fluid loading protocol compared to a more 'restrictive' protocol on hemodynamics and mortality in pigs in which septic shock had been induced. It appears that the former protocol was associated with higher mortality in spite of improved hemodynamics compared to the latter. The results of the paper are discussed here in view of the scope and mechanisms of these findings. With regard to fluid resuscitation, they indicate that too much of an otherwise good thing is harmful, even if overhydration and edema formation seem to have been prevented. They also do not exclude a specific toxic effect of the larger volumes of hydroxyethyl starch in the 'liberal' strategy. The precise nature of a toxic effect remains obscure, however, but may involve the kidneys.  相似文献   
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Background Post‐inflammatory hyperpigmentation (PIH) is a common occurrence in patients with acne vulgaris, particularly in those with skin of colour. Aims A previous study has demonstrated the benefit of tretinoin (retinoic acid) in the treatment of PIH; however, there is currently no standard protocol to evaluate change in PIH following treatment. Based on these findings, we performed a pilot, exploratory, blinded, intraindividual‐controlled methodology study that consisted of a photographic assessment protocol with facial mapping. Materials and methods The study was based on a secondary analysis of a phase 4, community‐based trial of 544 acne patients who were treated with tretinoin gel microsphere 0.04% or 0.1%. Only patients with Fitzpatrick types III–V (skin of colour) were included in the study; subjects with Fitzpatrick skin type VI were excluded because the photographic assessment did not allow for proper evaluation. Results Despite the small number of subjects evaluated (n = 25), the results revealed consistent assessment of improvement in PIH between two independent graders (weighted κ = 0.84). Conclusion Further study with a larger population is recommended to validate the accuracy of this method.  相似文献   
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Background  

In patients with type 2 diabetes, the risk for cardiovascular disease is substantial. To achieve a more favourable risk profile, lifestyle changes on diet, physical activity and smoking status are needed. This will involve changes in behaviour, which is difficult to achieve. Cognitive behavioural therapies focussing on self-management have been shown to be effective. We have developed an intervention combining techniques of Motivational Interviewing (MI) and Problem Solving Treatment (PST). The aim of our study is to investigate if adding a combined behavioural intervention to managed care, is effective in achieving changes in lifestyle and cardiovascular risk profile.  相似文献   
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We evaluated the performance of the SoftPerm combined rigid gas permeable (RGP) and hydrogel lens for the visual correction of 49 eyes (30 patients) with irregular astigmatism. Follow-up was up to 15 months. An attempt was also made to compare the SoftPerm lens to its predecessor, the Saturn II lens. The most common etiology for irregular astigmatism was keratoconus. Others etiologies were penetrating keratoplasty and refractive surgery. Visual acuity improved significantly. Only two eyes were best corrected to 20/20 before fitting whereas, 13 eyes saw 20/20 after fitting. The rate of lens replacement was 0.22 lenses per eye per month. A variety of complications occurred, including corneal staining, abrasions, and edema. Complications also reflected the relative difficulty of handling of the lens, yet no vision threatening complications occurred. Overall, the SoftPerm lens is a vast improvement over the Saturn II and is a reasonable means of correction of irregular astigmatism.  相似文献   
49.

Background

Tamoxifen, used as adjuvant therapy for carcinoma breast in postmenopausal women to prevent relapse has estrogenic effect on the endometrium.

Methods

104 patients on tamoxifen for more than six months were subjected to a clinical examination and transvaginal sonography. Patients with endometrial thickness > 8 mm were further evaluated by hysteroscopy and endometrial biopsy.

Results

35(34%) patients were symptomatic. The average endometrial thickness was 11.2 mm which correlated with duration of tamoxifen use. 27(48%) patients had abnormal hysteroscopic findings. 35 (63%) of endometrial biopsies revealed abnormal endometrium. One case of endometrial carcinoma was diagnosed. The results were statistically analysed. There is a significant association between symptomatic status and endometrial thickness and duration of tamoxifen use.

Conclusion

All patients on long term tamoxifen should be annually screened for endometrial pathology.Key Words: Tamoxifen, Endometrium, Transvaginal sonography  相似文献   
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Placement of umbilical artery catheters was retrospectively reviewed in 181 newborns to evaluate random placement of catheter tip in the "high" position between T7 and T9 in the thoracic aorta of 127 infants and in the "low" position below 4 in the abdominal aorta of 54 infants. Group differences in gestational age, asphyxia, hypotension, respiratory disease, duration of catheterization, or infusate type were not significant. Cyanosis or blanching in the low extremities occurred in 67% of the "low" group and 21% of the "high" group ( P < .001). Hematuria occurred in 39% of the "low" group and 21% of the "high" group ( P < .05). High placement appears to have fewer complications. Prompt intervention by neonatal nurse practitioners can help reverse complications that occur during umbilical artery catheterizations.  相似文献   
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