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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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Natural killer (NK) cell cytotoxicity was assessed using peripheral blood mononuclear cells from 103 healthy volunteers and 51 cancer patients. Peripheral blood cells were assessed by flow cytometry, and cytotoxicity in a standard 4-hour Cr-51-release assay using K562 cells as targets. Anti-CD3 and anti-CD16 mAb significantly enhanced cytoxicity in vitro. NK cell numbers correlated with levels of cytotoxicity. Patients with liver metastases had significantly more CD3+ lymphocytes coexpressing NK markers than patients without liver involvement. These CD3+ NK cells may also mediate cytotoxicity. Enhancement of cellular cytotoxicity by anti-CD3 and anti-CD16 may be of use in cancer immunotherapy protocols.  相似文献   
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Low concentrations of monoclonal antibodies (mAb) specific for the CD3 component of the T cell receptor complex (TcR) may be both immunosuppressive or potent activators of T cell function in vitro depending upon the experimental situation. The anti-CD3 mAb OKT3 is imnmunosuppressive at high doses (5 mg/day for 10 to 14 days) in transplant patients. We undertook a preliminary study to investigate the effect of a single intravenous injection of 50 mu g to 0.5 mu g of OKT3 mAb in cancer patients. OKT3 modulated cytotoxicity with minimal clinical toxicity at low doses and may be of use in cancer immunotherapy protocols.  相似文献   
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Patients with hepatic metastases from colorectal cancer appear to be resistant to most forms of therapy. Recent reports suggest synergism between systemically administered recombinant interleukin-2 (rIL-2) and 5-fluorouracil (5-FU) with responses documented in the treatment of advanced colonic tumours albeit with significant toxicity. Local continuous infusion of rIL-2 into selected sites may reduce toxicity and increase efficacy. We have assessed the feasibility of continuously infusing rIL-2 into the region of a hepatic metastasis in 3 patients via a catheter placed within the liver under ultrasound guidance in a regimen including systemic rIL-2 and 5FU.  相似文献   
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AIM: To provide information about the diagnostic and therapeutic impact of magnetic resonance imaging (MRI) and to compare the findings across diagnostic groups. MATERIALS AND METHODS: A prospective, observational study of 2017 consecutive referrals for MRI of the head, spine or knee at four imaging centres. Clinicians completed questionnaires before MRI stating initial diagnoses, diagnostic confidence and treatment plans. After imaging, a second questionnaire evaluated clinicians' revised diagnosis and treatment plans in the light of imaging findings. Patients were grouped into nine diagnostic categories for analysis. Comparison between pre- and post-imaging was used to assess the diagnostic and therapeutic impact of MRI. RESULTS: In seven of nine diagnostic groups MRI findings were associated with a diagnostic impact. Diagnoses were revised or discarded following normal MR findings and diagnostic confidence was increased by confirmative MR findings. There was no statistically significant diagnostic impact for suspected pituitary or cerebello-pontine angle lesions. In five of nine diagnostic groups (knee meniscus, knee ligament, multiple sclerosis, lumbar and cervical spine) MRI findings had a clear impact on treatment plans. CONCLUSION: This study demonstrates that in most diagnostic categories, MRI influences diagnosis and treatment. However, experimental studies are needed to prove that these diagnostic and therapeutic impacts lead to improved health.Hollingworth (2000). Clinical Radiology55, 825-831.  相似文献   
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Assessing outcome in lumbar disc surgery using patient completed measures   总被引:3,自引:0,他引:3  
Measuring outcome after spinal surgery is difficult. The objective of this study was to assess the use of four measures in establishing outcome in patients undergoing lumbar discectomy. Forty-six consecutive patients who had undergone two operations for lumbar disc prolapse and 54 patients who had undergone one operation for the same condition over the same period were identified. The SF-36 questionnaire was used to assess general health. The Roland-Morris questionnaire and a simple modification of the Roland-Morris questionnaire were used to assess back and leg related disability, respectively. Analogue pain scales were used to measure back pain and sciatica. The SF-36 scores revealed significantly worse health status in the two operation compared with the one operation patients and in all patients compared with the normal population. Using the Roland-Morris and the leg disability questionnaires, patients who had undergone two operations reported significantly worse disability (Roland-Morris, 53%, poor outcome) than those who had undergone one operation (Roland-Morris, 19%, poor outcome). There was significantly greater back disability than leg disability in both groups of patients and this was confirmed by the analogue pain scales. In patients who had undergone two operations, 25% classified their back pain as very bad or unbearable, and 22.5% described very bad or unbearable leg pain. For the one operation patients these figures were 9.5 and 2.4%, respectively. The results demonstrate that both generic and condition specific patient completed measures have the potential to detect differences in outcome between patients who have undergone either one or two lumbar disc operations. The study provides support for the use of these patient completed measures in assessing outcome in lumbar disc surgery.  相似文献   
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Some individuals exhibit a weak satiety response to food and may be susceptible to overconsumption. The current study identified women showing consistently low or high satiety responses to standardised servings of food across four separate days and compared them on behavioural, psychological and physiological risk factors for overeating and future weight gain. In a crossover design, 30 female participants (age: 28.0 ± 10.6; body mass index (BMI): 23.1 ± 3.0) recorded sensations of hunger in the post-prandial period following four graded energy level breakfasts. Satiety quotients were calculated to compare individuals on satiety responsiveness across conditions. Body composition, resting metabolic rate (RMR), energy intake, food reward and craving, and eating behaviour traits were assessed under controlled laboratory conditions. A distinct low satiety phenotype (LSP) was identified with good consistency across separate study days. These individuals had a higher RMR, greater levels of disinhibition and reported feeling lower control over food cravings. Further, they consumed more energy and exhibited greater wanting for high-fat food. The inverse pattern of characteristics was observed in those exhibiting a consistently high satiety phenotype (HSP). Weak satiety responsiveness is a reliable trait identifiable using the satiety quotient. The LSP was characterised by distinct behavioural and psychological characteristics indicating a risk for overeating, compared to HSP.  相似文献   
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