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111.
OBJECTIVES: Slow potentials appearing during simple repetitive acral limb movement were investigated. Twenty-six patients suffering from drug resistant partial epilepsies and explored with implanted intracerebral electrodes were examined using two protocols. METHODS: In 18 patients, readiness potential (RP), in 13 patients contingent negative variation (CNV), and in 7 patients both protocols, were tested. The recordings from leads with evident pathological EEG activity were excluded from evaluation. The results concerning the slow potentials preceding the movements in RP and CNV protocols have already been published. RESULTS: The movement-accompanying slow potentials (MASP) were polyphasic or monophasic, started before or during the movement. In the primary motor cortex they followed the pre-movement potentials depending on the protocol: in the RP paradigm they were present only contralateral to the movement, but were bilateral in the CNV protocol. In other areas they either followed the potentials preceding the movement, in some cases with opposite polarity, or they occurred alone. MASP was recorded in motor and supplementary motor, premotor and prefrontal, midtemporal, somatosensory, superior parietal and cingular cortices. The cingular cortex was heavily involved in the self-paced movements but rarely in the cued movements. CONCLUSION: The major involvement of the cingular gyrus contrasted with the absence of slow potentials in temporal limbic structures. MASP is evidently a heterogenic phenomenon. Its genesis could be involved in a spread of information through the relevant structures.  相似文献   
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We attempted to determine health and economic outcomes from the perspective of an integrated health system of administering enoxaparin 30 mg twice/day versus heparin 5000 U twice/day for prophylaxis against venous thrombosis after major trauma. A decision-analytic model was developed from best literature evidence, institutional data, and expert opinion. We assumed that 40% of proximal deep vein thromboses (DVTs) and 5% of distal DVTs are diagnosed and confirmed with initial or repeat duplex scanning; 50% of undiagnosed proximal DVTs result in pulmonary embolism; 2% and 1% of undiagnosed proximal DVTs will lead to readmission for DVT and pulmonary embolism, respectively, and pulmonary embolism-related mortality rates range from 8-30%. Length of hospital stay data and 1996 institutional drug use and acquisition cost data were used to estimate the cost of enoxaparin and heparin therapy. Diagnosis and treatment costs for DVT and pulmonary embolism were derived from institutional charge data using cost:charge ratios. A second analysis of patients with lower extremity fractures was completed. One-way and multiway sensitivity analyses were performed. For 1000 mixed trauma patients receiving enoxaparin versus heparin, our model showed that 62.2 (95% CI -113 to -12) DVTs or pulmonary emboli would be avoided, resulting in 67.6 (8 to 130) life-years saved at a net cost increase of $104,764 (-$329,300 to $159,600). Enoxaparin versus heparin resulted in a cost of $1684 (-$3600 to $9800) for each DVT or pulmonary embolus avoided and a discounted cost/life-year saved of $2303 (-$8100 to $19,000). For 1000 patients with lower extremity fractures, enoxaparin versus heparin resulted in a cost of $751 (-$4200 to $3300) for each DVT or pulmonary embolus avoided and a discounted cost/life-year saved of $1017 (-$10,200 to $6300). Although enoxaparin increases overall health care costs, it is associated with a cost/additional life-year saved of only $2300, which is generally lower than the commonly used hurdle rate of $30,000/life-year saved. The cost-effectiveness ratio is more favorable in patients with lower extremity fractures than in the general mixed trauma population.  相似文献   
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Under in vitro conditions, muscle larvae of Trichinella spiralis secreted minute amounts of a cysteine proteinase into the outer environment from the stichosome. The proteinase hydrolyzed azocoll at pH 5.0 but not a number of synthetic N-blocked and N-unsubstituted proteinase substrates at this pH. The reducing compound dithioerythritol enhanced the enzyme activity, but the thiol-blocking reagent sodium-p-hydroxymercuribenzoate (0.1 mM) was without effect. Phenylmethylsulfonyl fluoride (PMSF) (2 mM) and leupeptin (100 mM) produced partial and complete inhibition, respectively, whereas soybean trypsin inhibitor, pepstatin A, and 1,10-phenanthroline were non-inhibitory. Calcium (1 mM) produced a slight decrease in the activity that was reversed by 1 mM EGTA. Although multiple proteinase activities were detected histochemically in the somatic muscles, stichosome, midgut, and genital primordium of the muscle larvae, none of these enzymes appeared to be the one secreted. Several histochemically demonstrable proteinases were also found in the cells of 48- to 72-h-old juveniles of the parasite. One was localized in the esophageal lumen and at or around the anterior esophagus of the larvae, where developing stichocytes are believed to occur. The proteinase hydrolyzed N-acetyl-L-methionine-L-naphthyl ester and was sensitive to the metal cation-complexing compound EGTA as well as to PMSF, an inhibitor of serine proteinases.  相似文献   
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A longitudinally linked data set for Georgia was used to identify characteristics, including previous prenatal care use and complications at the first birth, associated with prenatal care use in the second pregnancy among 8,224 African-American women. More than 70% of the women who were < 25 years of age at their first birth (younger women) and almost 40% of women who were > or = 25 years at their first birth received inadequate care with at least one of their first two births. Women who received inadequate care in their first pregnancy were more likely to receive inadequate care in their second pregnancy than women who received adequate care in their first pregnancy. Younger women with a history of a stillbirth, neonatal death, or vacuum extraction were less likely to receive inadequate care in their subsequent pregnancy. Although this study was not able to evaluate the content of prenatal care, it suggested that many African-American women may not receive sufficient care to prevent adverse pregnancy outcomes. Women who receive inadequate care in their first pregnancy must be targeted for interventions that help them overcome economic, situational, or attitudinal barriers to receiving adequate care in their next pregnancy.  相似文献   
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OBJECTIVE: This study tested the hypothesis that gut stasis induced by parenteral morphine sulfate (MS) leads to enhanced bacterial translocation in rats on total parenteral nutrition (TPN). SUMMARY BACKGROUND DATA: TPN and MS are common adjuncts in the care of critically ill patients. TPN is known to provoke a variable degree of translocation. MS induces gut stasis with an accompanying bacterial overgrowth. The effect of these two treatments in combination on translocation is not known. METHODS: Rats were provided with central and subcutaneous lines for the continuous infusion of nutrients and drugs, respectively. Intestinal transit was assessed by the caudal movement of a fluorescent marker intubated into the proximal duodenum. Quantitative bacteriology was carried out from various segments of the gut and from ileocecal mesenteric lymph nodes (MLN), spleen, liver, and systemic blood obtained by cardia puncture on sacrifice at 96 hours. RESULTS: Transit was unchanged by TPN alone but prolonged when given in combination with MS. Bacterial overgrowth was also enhanced by MS and increased the bacterial translocation to MLN from 50% of animals with TPN, to 100% in those receiving both TPN and MS; the colony-forming units per MLN increased from 33 +/- 14 with TPN alone to 2079 +/- 811 (STD) with TPN plus MS. Furthermore, no bacteria were found at systemic sites with TPN alone, but in 93.3% of animals receiving TPN and MS. In a subgroup of rates provided with glutamine in TPN, the TPN plus MS effects on translocation were not reversed. CONCLUSIONS: These observations demonstrate the important role that morphine plays in promoting translocation, presumably by disrupting fasting motility and enhancing bacterial overgrowth.  相似文献   
119.
To say that enrolled nurse Liz Roberts is dedicated to her work with continuing care patients at Palmerston North Hospital is an understatement. Her care for them extends even to her days off.  相似文献   
120.
Significant increases in serum levels of IgE have often been observed in allogeneic bone marrow transplantation patients and have generally been thought to be diagnostic of graft-versus-host disease (GVHD), rather than an agent involved in the pathogenesis of the disease. Experimental murine GVHD models have also indicated associations of hyper-IgE activity, yet the role of IgE in GVHD pathogenesis has never been tested directly. In the current study, we have tried to address this issue by using recently developed peptide analog antagonists for the interaction of IgE with the Fc epsilon RI receptor, which is necessary for triggering mast cells and other cell types when cross-linked by antigens. A synthetic cyclized 13-amino acid peptide was previously designed from the modeled C-C' loop region of the Fc epsilon RI alpha-chain and was found to act as a competitive inhibitor of IgE-Fc epsilon RI alpha binding. The peptide was generated in two forms, a cyclic L-(L-IgEtide) and retro D-amino acid composition (rDIgEtide), the latter to increase resistance to protease degradation for in vivo applications. These two inhibitor peptides were then used to test the hypothesis that IgE could be involved in the pathogenesis of acute GVHD, in the B10.D2-->DBA/2 (900 cGy) strain combination, with GVHD directed to minor histocompatibility antigens. Both peptides demonstrated significant inhibition of the development of lethal GVHD, supporting the involvement of IgE at some level of disease pathogenesis.  相似文献   
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