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91.
Hepatic encephalopathy and gastrointestinal (GI) bleeding are the most serious complications in cirrhosis. The purpose of this study was to examine survival after the first episode of GI bleeding or coma, or both, and to identify variables associated with the subsequent survival in 284 consecutive patients with cirrhosis admitted to one division of hepatology over a period of 81 months. Patients who only bled had markedly longer survival than those who only had coma, whereas those who had both bleeding and coma had by far the poorest survival, only 15% being alive 1 year later. Several other variables showed a significant association with survival. In a Cox multiple regression analysis the following four variables showed significant association with a short survival: coma and bleeding at the episode, ascites, low prothrombin index, and high serum creatinine. The prognostic index derived from the Cox model, which was validated by a split-sample testing technique, may be used to refine prognostic estimation in this subgroup of severely ill cirrhotic patients.  相似文献   
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In a prospective randomized study involving 32 male subjects aged 18 to 38, the effects of flunitrazepam (0.25 to 2 mg/70 kg), lormetazepam (0.5 to 4 mg/70 kg), midazolam (1.5 to 12 mg/70 kg) and diazepam (4 to 32 mg/70 kg) on the beta-activity (13 to 20/s) were investigated. Each subject received four benzodiazepine injections of increasing dosage. The doses were selected so that the lowest had only a slight effect on the test person's condition, while the highest resulted in deep sedation. The increase in beta-activity started off with a latency of 30 to 60 s; it was proportional to the dosage and reached its maximum between the 2. and 3. minutes. The subsequent decrease in beta-activity could be represented by an exponential function. The effect could be cancelled temporarily by administering repeated doses of the specific antagonist, flumazenil (0.1, 0.3 and 0.9 mg/70 kg). The method is suited for describing pharmacodynamic processes, determining equipotential doses of benzodiazepines and detecting the interaction between benzodiazepines and specific antagonists.  相似文献   
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Background

Surfactant protein D (SP-D) is a collection that plays important roles in modulating host defense functions and maintaining phospholipid homeostasis in the lung. The aim of current study was to characterize comparatively the SP-D response in bronchoalveolar lavage (BAL) and serum in three murine models of lung injury, using a validated ELISA technology for estimation of SP-D levels.

Methods

Mice were exposed to lipopolysaccharide, bleomycin, or Pneumocystis carinii (Pc) and sacrificed at different time points.

Results

In lipopolysaccharide-challenged mice, the level of SP-D in BAL increased within 6 h, peaked at 51 h (4,518 ng/ml), and returned to base level at 99 h (612 ng/ml). Serum levels of SP-D increased immediately (8.6 ng/ml), peaked at 51 h (16 ng/ml), and returned to base levels at 99 h (3.8 ng/ml). In a subacute bleomycin inflammation model, SP-D levels were 4,625 and 367 ng/ml in BAL and serum, respectively, 8 days after exposure. In a chronic Pc inflammation model, the highest level of SP-D was observed 6 weeks after inoculation, with BAL and serum levels of 1,868 and 335 ng/ml, respectively.

Conclusions

We conclude that serum levels of SP-D increase during lung injury, with a sustained increment during chronic inflammation compared with acute inflammation. A quick upregulation of SP-D in serum in response to acute airway inflammation supports the notion that SP-D translocates from the airways into the vascular system, in favor of being synthesized systemically. The study also confirms the concept of using increased SP-D serum levels as a biomarker of especially chronic airway inflammation.  相似文献   
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Aims/IntroductionTo examine the association between cholesterol efflux capacity (CEC) of serum high‐density lipoprotein (HDL) and cognitive function and brain structures in older people with diabetes mellitus.Materials and MethodsParticipants of a randomized placebo‐controlled trial of 27‐month vitamin B12 supplementation in older people with diabetes mellitus, which showed no effect on cognition, were further followed up at month 72. Cognitive tests included the Clinical Dementia Rating scale, Neuropsychological Test Battery in memory, executive function and psychomotor speed. Brain magnetic resonance imaging scans were carried out in a subset at baseline, month 27 and month 45. Fasting serum at baseline, month 9, month 27 and month 72 were analyzed for adenosine triphosphate‐binding cassette transporter A1‐mediated CEC of HDL and apolipoprotein A1 (ApoA1).ResultsSerum HDL cholesterol at baseline was associated with better executive and memory function at follow up. Serum ApoA1 was associated with a better memory Z‐score at month 18. Serum CEC and ApoA1 were not associated with Clinical Dementia Rating scale, Neuropsychological Test Battery, hippocampal volume and white matter disease on magnetic resonance imaging at baseline and whole brain atrophy rates. They were also not associated with cognitive function at month 27 and 72 on multilevel modeling. CEC and ApoA1 decreased significantly from baseline to month 27. Faster decliners in CEC had a greater increase in brain peak width of skeletonized mean diffusivity.ConclusionsHigher serum HDL cholesterol was associated with more favorable changes in memory and executive function in older people with diabetes mellitus. However, this was not due to CEC or ApoA1. A decline in CEC was associated with small vessel disease in the brain.  相似文献   
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The costs and impacts associated with the recruitment and retention of nurses are substantial. In rural areas, these efforts are hampered by the recurring maldistribution of available nurses away from such environments. Based on a survey of 195 directors of nursing (DONs) practicing in rural community hospitals, the authors compare administrative assessments of recruitment and retention efforts of DONs practicing in various-sized rural facilities. Current full-time equivalent registered nurse staff vacancy rates are also reported in relation to these differing assessments.  相似文献   
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