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Adult respiratory distress syndrome (ARDS) remains a major problem in intensive care medicine. While the triggers are not well understood, the process often involves generalized neutrophil activation and sequestration in the lung which initiate inflammatory cascades. These effects can be localized to the pulmonary tissues as well as diffusely throughout the body. Should the latter occur, the patient presents with multiple organ failure (MOF). Attempts to interfere with this series of events have included replacement therapy for surfactant and its components because of observations that the natural surfactant mechanisms are impaired or damaged. The effectiveness of replacement therapy has been tested in various protocols involving synthetic composites and animal (bovine) surfactants. While major differences in protocol design have led to conflicting results, there appears to be evidence that installation of bovine surfactant can reduce mortality in ARDS. A major limitation in adult therapeutics utilizing surfactant is the method of delivery; direct instillation utilizes large quantities, thus limiting its availability. Aerosolized therapy may have promise if smaller amounts delivered by this modality are more effective. Inhaled nitric oxide may also have therapeutic potential in ARDS. By improving ventilation perfusion mismatch, ventilatory requirements can be reduced.  相似文献   
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Background: Liver dysfunction as a result of impaired oxygen availability frequently occurs following hemorrhage and contributes to delayed mortality. Artificial oxygen carriers may improve oxygen supply to vital organs while avoiding the need for allogeneic transfusion.

Methods: Rats were subjected to hemorrhagic hypotension (mean arterial pressure = 35-40 mmHg for 120 min) and were subsequently resuscitated with (1) stored whole rat blood, (2) pentastarch, or (3) pentastarch combined with perflubron emulsion (PFE; 2.7 or 5.4 g/kg body weight), a second-generation artificial oxygen carrier. Recovery of liver adenosine triphosphate, hepatocellular injury, and expression of glutamine synthetase 1, a gene that is induced by exposure of hepatocytes to low partial pressure of oxygen, were studied at 4 h of resuscitation.

Results: Stored whole blood or pentastarch failed to restore liver adenosine triphosphate concentrations after prolonged shock as compared to sham controls and resulted in increased gene expression of glutamine synthetase 1. Addition of 2.7 g PFE/kg restored liver adenosine triphosphate to control, whereas 5.4 g PFE/kg resulted in adenosine triphosphate concentrations significantly above control. Improved hepatocellular oxygen supply was also confirmed by restoration of the physiologic expression pattern of glutamine synthetase 1. Serum enzyme concentrations were highest after resuscitation with stored blood, whereas addition of PFE failed to further decrease enzyme concentrations as compared to pentastarch alone.  相似文献   

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High-risk combinations of recipient and graft characteristics are poorly defined for liver retransplantation (reLT) in the current era. We aimed to develop a risk model for survival after reLT using data from the European Liver Transplantation Registry, followed by internal and external validation. From 2006 to 2016, 85 067 liver transplants were recorded, including 5581 reLTs (6.6%). The final model included seven predictors of graft survival: recipient age, model for end-stage liver disease score, indication for reLT, recipient hospitalization, time between primary liver transplantation and reLT, donor age, and cold ischemia time. By assigning points to each variable in proportion to their hazard ratio, a simplified risk score was created ranging 0–10. Low-risk (0–3), medium-risk (4–5), and high-risk (6–10) groups were identified with significantly different 5-year survival rates ranging 56.9% (95% CI 52.8–60.7%), 46.3% (95% CI 41.1–51.4%), and 32.1% (95% CI 23.5–41.0%), respectively (< 0.001). External validation showed that the expected survival rates were closely aligned with the observed mortality probabilities. The Retransplantation Risk Score identifies high-risk combinations of recipient- and graft-related factors prognostic for long-term graft survival after reLT. This tool may serve as a guidance for clinical decision-making on liver acceptance for reLT.  相似文献   
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Annals of Surgical Oncology - The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to...  相似文献   
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To verify occupational neurotoxic effects it will be necessary to enlist the help of clinical psychologists and psychiatrists. However, no unified professional test battery exists to date. 119 healthy workers (26 lead-exposed, 45 exposed to mixed organic solvents, and 48 controls) were tested using uniformly standardised psychological and psychiatric methods. Long-term lead-exposed employees showed an increased number of psychoneurovegetative symptoms and deficits in attention performance according to the results of the Seeber-PNF and the Brickenkamp-d2-tests. There was no difference between the control group and persons exposed to the organic solvents test. Many parameters correlated to the dose of the toxic agent in the lead-exposed group. SCL-90-R, AMDP, and HAMD merely hinted at differences between the exposed subjects and the controls. Psychological and pathopsychological methods are necessary but will not suffice to detect early effects after long-term exposure to lead or organic solvents.  相似文献   
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PURPOSE: Although there is wide recognition of the usefulness of improving physicians' communication skills, no studies have yet assessed the efficacy of post-training consolidation workshops. This study aims to assess the efficacy of six 3-hour consolidation workshops conducted after a 2.5-day basic training program. METHODS: Physicians, after attending the basic training program, were randomly assigned to consolidation workshops or to a waiting list. Training efficacy was assessed through simulated and actual patient interviews that were audiotaped at baseline and after consolidation workshops for the consolidation-workshop group, and approximately 5 months after the end of basic training for the waiting-list group. Communication skills were assessed according to the Cancer Research Campaign Workshop Evaluation Manual. Patients' perceptions of communication skills improvement were assessed using a 14-item questionnaire. RESULTS: Sixty-three physicians completed the training program. Communication skills improved significantly more in the consolidation-workshop group compared with the waiting-list group. In simulated interviews, group-by-time repeated measures analysis of variance showed a significant increase in open and open directive questions (P =.014) and utterances alerting patients to reality (P =.049), as well as a significant decrease in premature reassurance (P =.042). In actual patient interviews, results revealed a significant increase in acknowledgements (P =.022) and empathic statements (P =.009), in educated guesses (P =.041), and in negotiations (P =.008). Patients interacting with physicians who benefited from consolidation workshops reported higher scores concerning their physicians' understanding of their disease (P =.004). CONCLUSION: Consolidation workshops further improve a communication skills training program's efficacy and facilitate the transfer of acquired skills to clinical practice.  相似文献   
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Objective To assess the effects of medroxyprogesterone acetate on bone density in women who have had a hysterectomy
Design Randomised, double-blind, placebo-controlled trial of medroxyprogesterone acetate 10 mg, 20 mg or placebo as an adjunct to oestrogen therapy.
Participants One hundred and twenty-three women, aged 18 to 45 years and currently receiving daily oestrogen, who presented at a university-based rheumatology practice.
Interventions The women were randomly assigned to receive either medroxyprogesterone acetate 10 mg, 20 mg or placebo daily beginning on day 15 of each month for one year. Forty-one women were randomised into each group.
Main outcome measure The primary outcome measurement was the percentage of change from baseline in bone mineral density of the lumbar spine (L2–L4). Secondary outcome measures included differences in femoral neck bone density, cholesterol and triglyceride levels between groups.
Results At one year, change in bone mineral density did not differ between either the treatment or placebo groups. Medroxyprogesterone acetate 20 mg and 10 mg led to statistically significant reductions in very low density lipoprotein cholesterol, total triglycerides, and very low density lipoprotein triglycerides when compared with placebo. Medroxyprogesterone acetate 20 mg also led to a statistically significant reduction in high density lipoprotein cholesterol, high density lipo-protein-2 cholesterol, and high density lipoprotein-2 triglycerides.
Conclusions Medroxyprogesterone acetate at either dose as an adjunct to oestrogen did not improve bone mineral density at one year when compared with placebo. Medroxyprogesterone acetate 10 mg may not adversely affect lipids. Medroxyprogesterone acetate 20 mg, however, did reduce high density lipoprotein cholestrol and therefore may increase cardiovascular risk.  相似文献   
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Endoscopic frontal sinus surgery is still considered difficult, risky to perform, and likely to result in a high failure rate. We have previously reported on our technique of endoscopic frontal sinus surgery, stressing the importance of identification and preservation of natural outflow tract. Our study of frontal sinus anatomy shows that the mean frontal ostium anterior—posterior and transverse dimensions are 7.22 ± 2.78 mm and 8.92 ± 2.95 mm, respectively; therefore, dissection of obstructive structures in frontal recess leads to a wide opening of frontal sinus outflow. A key surgical landmark in our technique is the superior attachment of the uncinate process. This article provides an update of the surgical anatomy of the frontal recess region and our surgical technique, as well as a discussion of our approach to frontal sinus revision surgery.  相似文献   
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