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41.
Interleukin 2 (IL-2) is an essential mediator of the immune response and has also been shown to be protective in experimental models of sepsis. Macrophages have IL-2 receptors but their function is unknown. We investigated the effect of IL-2 on Kupffer cells, the fixed macrophages of the liver, using an in vitro rat hepatocyte-Kupffer cell coculture system. In this model, endotoxin (lipopolysaccharide) triggers Kupffer cells to induce suppression of hepatocyte protein synthesis. We found that pretreatment with 10 U/mL or more of IL-2 primed Kupffer cells, significantly reducing the concentration of lipopolysaccharide necessary to trigger Kupffer cell-mediated suppression of hepatocyte protein synthesis. Higher concentrations of IL-2 (greater than or equal to 1 x 10(4) U/mL) alone were capable of priming and triggering Kupffer cells to suppress hepatocyte protein synthesis. These data show that IL-2 increases Kupffer cell sensitivity to endotoxin, suggesting that IL-2 may play an important role in regulating macrophage responses to septic stimuli.  相似文献   
42.
BACKGROUND: Primary care requests for radiographs of the lumbar spine have come under increasing scrutiny. Guidelines aiming to reduce unnecessary radiographs by limiting referrals to patients at high risk of serious disease have been widely distributed. Trial evidence suggests that guidelines can reduce radiography referrals. It is not clear whether this reduction has been achieved in routine practice. AIM: This study, using routine data, was conducted to measure trends in pnmary care referrals for lumbar spine radiography at two hospitals between 1994 and 1999. DESIGN OF STUDY: Analysis of primary care requests for lumbar spine radiography from computerised records. SETTING: Addenbrooke's Hospital, Cambridge (1 July 1994 to 30 June 1999), and Ipswich General Hospital (1 July 1995 to 30 June 1999), United Kingdom. METHOD: All primary care requests for lumbar radiography were identified electronically from computerised information systems. A random sample of 2100 radiography reports were classified according to clinical importance. These classifications were used to examine whether the proportion of radiographs demonstrating potentially more serious findings had increased between 1994 and 1999. RESULTS: There was no evidence that primary care referrals for radiography of the lumbar spine had decreased between 1994 and 1999 at either hospital. General practitioners did not progressively refer more high-risk patients for lumbar radiography. Only a small proportion of patients had important radiographic findings that might warrant specialist referral or specific therapy. CONCLUSION: The implementation of diagnostic guidelines offers much to the NHS. However in these two hospitals, the reduction in radiograph utilisation evident in trials was not achieved. Guideline development is a resource intensive process; distribution must be supported by more effective implementation strategies.  相似文献   
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Nonmotor symptoms (NMS) of Parkinson's disease (PD) are not well recognized in clinical practice, either in primary or in secondary care, and are frequently missed during routine consultations. There is no single instrument (questionnaire or scale) that enables a comprehensive assessment of the range of NMS in PD both for the identification of problems and for the measurement of outcome. Against this background, a multidisciplinary group of experts, including patient group representatives, has developed an NMS screening questionnaire comprising 30 items. This instrument does not provide an overall score of disability and is not a graded or rating instrument. Instead, it is a screening tool designed to draw attention to the presence of NMS and initiate further investigation. In this article, we present the results from an international pilot study assessing feasibility, validity, and acceptability of a nonmotor questionnaire (NMSQuest). Data from 123 PD patients and 96 controls were analyzed. NMS were highly significantly more prevalent in PD compared to controls (PD NMS, median = 9.0, mean = 9.5 vs. control NMS, median = 5.5, mean = 4.0; Mann-Whitney, Kruskal-Wallis, and t test, P < 0.0001), with PD patients reporting at least 10 different NMS on average per patient. In PD, NMS were highly significantly more prevalent across all disease stages and the number of symptoms correlated significantly with advancing disease and duration of disease. Furthermore, frequently, problems such as diplopia, dribbling, apathy, blues, taste and smell problems were never previously disclosed to the health professionals.  相似文献   
46.
Dopamine agonists have been recommended as early treatment for Parkinson's disease (PD), alone or combined with levodopa. Piribedil is a non-ergot selective D(2)/D(3) agonist with alpha(2) antagonist properties shown to be effective in the treatment of PD. This 12-month international, randomized, double-blind trial aimed to assess the efficacy of piribedil 150 mg versus bromocriptine 25 mg, in early combination with levodopa in Stage I to III PD patients. Motor efficacy was assessed using the Unified Parkinson's Disease Rating Scale (UPDRS III, Items 18-31) as improvement from baseline. Response rate was defined as a 30% improvement. Among the 425 randomly assigned patients, 178 were also included in a substudy on cognitive follow-up evaluated by a dysexecutive syndrome oriented battery. A relevant improvement in UPDRS III over the 12-month study duration was observed both in the piribedil and bromocriptine groups (-7.9 +/- 9.7 points from baseline versus -8.0 +/- 9.5; not significant [n.s.]) with a response rate of 58.4% and 55.3% (n.s.), respectively. Piribedil and bromocriptine resulted in similar improvement on all UPDRS III subscores. Piribedil patients required less levodopa dose increase than those on bromocriptine. Cognitive performance remained generally unchanged in both groups, with a significant effect of piribedil limited to the Wisconsin Card Sorting Test. An overall good tolerability of piribedil was observed. Early combination of piribedil 150 mg with levodopa resulted in significant long-term improvement of all motor symptoms in PD patients insufficiently controlled by levodopa alone. Taking into account both efficacy and acceptability in the long-term, piribedil proved in this bromocriptine controlled study to be an effective and safe treatment for PD.  相似文献   
47.
The effects of progesterone treatment on bupivacaine arrhythmogenicity in beating rat heart myocyte cultures and on anesthetized rats were determined. After determining the bupivacaine AD50 (the concentration of bupivacaine that caused 50% of all beating rat heart myocyte cultures to become arrhythmic), we determined the effect of 1-hour progesterone HCl exposure on myocyte contractile rhythm. Each concentration of progesterone (6.25, 12.5, 25, and 50 micrograms/ml) caused a significant and concentration-dependent reduction in the AD50 for bupivacaine. Estradiol treatment also increased the arrhythmogenicity of bupivacaine in myocyte cultures, but was only one fourth as potent as progesterone. Neither progesterone nor estradiol effects on bupivacaine arrhythmogenicity were potentiated by epinephrine. Chronic progesterone pretreatment (5 mg/kg/day for 21 days) caused a significant increase in bupivacaine arrhythmogenicity in intact pentobarbital-anesthetized rats. There was a significant decrease in the time to onset of arrhythmia as compared with control nonprogesterone-treated rats (6.2 +/- 1.3 vs. 30.8 +/- 2.5 min, mean +/- SE). The results of this study indicate that progesterone can potentiate bupivacaine arrhythmogenicity both in vivo and in vitro. Potentiation of bupivacaine arrhythmia in myocyte cultures suggests that this effect is at least partly mediated at the myocyte level.  相似文献   
48.
Thermoregulatory heat-loss responses at high ambient temperatures were studied in intact cats and those with bilateral electrolytic lesions in the pontine tegmentum during wakefulness (W), slow-wave sleep (SWS), paradoxical sleep (PS) and PS without atonia induced by the lesions. Panting (respiratory rate 90/min) was present W, SWS, and in some cases, during PS. The percentage of the PS episodes with panting was directly related ambient temperature. In intact cats at 30 °C, panting occurred in 8% of the PS episodes; at 35 °C, in 52%, and at 40 °C, in 77%. The percentage of PS episodes with panting higher in the pontine-lesioned cats (90% at 35 °C), probably another indication of the altered thermoregulation of such animals. Thermoregulatory responses to heat load, and thermoregulation in general, have previously been shown to be suppressed in PS. Because hypothalamic thermosensitive neurons lack thermal responses during PS, the partial activation of heat-loss responses observed here may depend upon the function of extrahypothalamic brainstem areas.  相似文献   
49.
We evaluated the effects of isoflurane anaesthesia and induced hypotension in 33 neurosurgical patients by electrocardiographic monitoring and serial cardiac enzyme measurements. An electrocardiogram (ECG) and serum enzymes were obtained preoperatively, intraoperatively and postoperatively in the recovery room and for three consecutive days. ECG leads II, V1 and V5 were monitored continuously during anaesthesia. Patients who had had a subarachnoid haemorrhage and a high incidence of abnormal preoperative ECG (42 per cent). Ten patients developed ECG changes intraoperatively, but these changes were unrelated to isoflurane-induced hypotension. Fifty-three per cent of patients developed an abnormal postoperative ECG. These abnormalities consisted mostly of nonspecific ST segment or T wave changes. At no time was there an elevation in cardiac enzyme activity. We found that nonspecific ECG changes are relatively common in patients undergoing vascular neurosurgical procedures. There was no enzymatic evidence of myocardial infarction and we can only speculate that these ECG changes are related to intracranial surgical manipulation.  相似文献   
50.
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