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101.
BACKGROUND: Surgeons have a reputation for decisiveness and self-confidence, which suggests that they may tolerate uncertainty poorly and therefore be less capable than other doctors of experiencing clinical equipoise. Their 'typical' behaviour is characteristic of the stable extrovert personality and so they may prefer spontaneous clinical judgement over randomized trials. The aim of this study was to compare personality dimensions and tolerance of uncertainty among surgeons and hospital physicians, to determine whether differences in either property might help to explain the apparently poor performance of surgeons in conducting randomized controlled trials. METHODS: This was a postal questionnaire study of 1000 consultant general surgeons and 1000 consultant physicians. Respondents completed a short self-assessment of Eysenck personality dimensions, Budner's Intolerance of Ambiguity scale and a short questionnaire about attitudes to randomized trials. Correlation and multiple regression analyses were performed. RESULTS: The response rate was 36.5 per cent. Physicians were more likely to be women (P < 0.001) and had spent 1 more year in academic posts than surgeons (P < 0.030). Surgeons were significantly more extrovert (P < 0.001) and less neurotic (P < 0.001) than physicians. Surgeons were significantly more intolerant of uncertainty than physicians (P = 0.007). Multivariate analysis identified age (P < 0.030) and sex (P = 0.015) as independent predictors of intolerance of uncertainty. The attitudes of surgeons and physicians to randomized trials were no different. CONCLUSION: Surgeons are not prejudiced against randomized trials, but their intolerance of uncertainty may inhibit them from deciding that an individual patient is suitable for trial entry. If more surgeons were female, this difference between surgeons and physicians might disappear.  相似文献   
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103.
Two patients had colonic perforation as a result of percutaneous nephrostomy placement followed by track dilatation and renal calculus removal. We present the technical aspects of nephrostomy placement and stone removal, as well as the clinical diagnosis and management of these cases. Both patients recovered well with conservative therapy and required no surgical intervention. This report reviews the anatomic considerations for percutaneous nephrostomy in patients undergoing renal stone removal.  相似文献   
104.
The objective of the present study was to determine the prevalence of hyperventilation syndrome in patients seen for vestibular assessment and to assess the clinical utility of the Nijmegen Questionnaire in this group. The Nijmegen Questionnaire and Dizziness Handicap Inventory (DHI) were administered prospectively to a consecutive series of 100 patients identified as candidates for vestibular assessment within the University Hospital Neuro-otology practice. Twenty-three per cent of patients seen for vestibular assessment were diagnosed with hyperventilation syndrome using the Nijmegen Questionnaire. Seventeen of these (74%) would have remained undetected had the Nijmegen questionnaire not been used. No relationship was found between vestibular assessment results and either Nijmegen or DHI scores. A significant correlation was found between DHI scores and Nijmegen Questionnaire scores (rho = 0.348, P = 0.0005). In conclusion, the Nijmegen Questionnaire is a quick, easy to administer and low-impact assessment tool for hyperventilation syndrome and is a useful adjunct to the otological consultation. Diagnosed patients can then be offered breathing control exercises as part of a vestibular rehabilitation programme.  相似文献   
105.
Delirium Tremens     
The varied clinical manifestations and management of 14 male patients with delirium tremens (DT) have been studied. Eight patients were initially hospitalised for diseases unrelated to ethanol abuse i.e. 2 each for gun shot wound, myocardial infarction and stroke, and one each for pneumonia and gastroenteritis. One patient was going through withdrawal because of prodrome of viral hepatitis before he was hospitalised for uncontrolled agitation and delirium. Two known cases of mild essential hypertension on dietary therapy reported for agitation, abnormal behaviour, a single episode of tonic clonic seizure and hypertensive encephalopathy as they could not/did not get alcohol for 3 days. Three patients presented denovo with DT without concomitant illness. The other features besides delirium and hallucinations were tremulousness in 10, tachycardia in 12, fever in 3, diaphoresis in 2 and tonic clonic seizures in 4 patients. The symptoms fluctuated markedly at short intervals and 2 patients did not have any features of sympathetic overactivity. Altered hepatic biochemical parameters and ketonuria with normal blood sugar were noted in 4 and one patients respectively. Other biochemical parameters including serum electrolytes were normal. CT scan brain done for 5 patients revealed subdural haematoma in one. Cerebro spinal fluid (CSF) and EEG findings were noncontributory. All made good recovery with heavy doses of intravenous vitamin B complex, glucose and oral benzodiazepine. Short course of haloperidol was used in 2 patients. Two patients developed pancreatitis during follow up. All patients made complete recovery, and 8 patients have been followed for 8 to 12 months without relapse. The reason for hospitalisation in such cases is often unrelated to alcohol abuse; hence a detailed history of alcoholism is mandatory to identify those at risk as well as for prompt treatment and decreasing the mortality.Key Words: Alcohol withdrawal, Concomitant illnesses, Delirium, Precipitating events  相似文献   
106.
Reynolds NA  Wagstaff AJ 《Drugs》2004,64(17):1957-1974
Insulin aspart (NovoRapid, NovoLog) is a short-acting insulin analogue, which has a faster onset and shorter duration of action than regular human insulin. Insulin aspart administered immediately before meals provided significantly greater improvements in glycosylated haemoglobin and better postprandial glycaemic control than regular human insulin administered 30 minutes before meals, when used in a basal-bolus regimen with neutral protamine Hagedorn (NPH) insulin, in randomised, nonblind studies in patients with type 1 diabetes mellitus. In patients with type 2 diabetes, insulin aspart provided similar glycaemic control to regular human insulin, administered in a basal-bolus regimen with NPH insulin. Small studies suggest that the use of insulin aspart in combination with oral hypoglycaemic agents may be beneficial. Insulin aspart, administered by continuous subcutaneous insulin infusion (CSII) provided better glycaemic control than insulin aspart multiple daily injection regimens in patients with type 1 (but not type 2) diabetes, and had similar efficacy to CSII with insulin lispro or regular human insulin in type 1 diabetes. Limited studies show insulin aspart to be effective in children, adolescents and young adults with type 1 diabetes. Insulin aspart had a tolerability profile similar to that of regular human insulin in clinical trials. The incidence of major or nocturnal hypoglycaemic events reported in patients receiving insulin aspart was lower than that of regular human insulin in several studies.In conclusion, insulin aspart, administered immediately before meals in a basal-bolus regimen with NPH insulin, provided better long-term glycaemic control than regular human insulin administered 30 minutes before meals in patients with type 1 diabetes, and was as effective as regular human insulin in patients with type 2 diabetes. A significantly lower risk of hypoglycaemia was seen in several trials. Insulin aspart CSII provided better glycaemic control than insulin aspart multiple daily subcutaneous injection (MDI) in patients with type 1 (but not type 2) diabetes and had similar efficacy to CSII with insulin lispro or regular human insulin in type 1 diabetes. Insulin aspart is an effective and well tolerated alternative to regular human insulin and insulin lispro for the maintenance of glycaemic control in patients with type 1 or 2 diabetes.  相似文献   
107.
Cheer SM  Wagstaff AJ 《Drugs》2004,64(3):323-346
Epoetin beta (NeoRecormon) is a recombinant form of erythropoietin. It increases reticulocyte counts, haemoglobin (Hb) levels and haematocrit. Epoetin beta administered subcutaneously once weekly corrected anaemia and had equivalent efficacy to that of epoetin beta administered three times weekly in patients with haematological malignancies. Subcutaneous epoetin beta reduced transfusion requirements and increased Hb levels versus no treatment in patients with solid tumours and chemotherapy-induced anaemia in nonblind, randomised trials. Anaemia and quality of life were also improved, and blood transfusion requirements were reduced to a significantly greater extent than placebo or no treatment (with supportive blood transfusion) in patients with haematological malignancies. Most patients were receiving chemotherapy. Subcutaneous epoetin beta was well tolerated by patients with cancer; adverse events with the drug occurred with a similar incidence to those with placebo or no treatment (with supportive blood transfusion). Hypertension was relatively uncommon with epoetin beta in clinical trials. Patients with haematological malignancies and a baseline platelet count > or =100 x 10(9)/L, Hb levels of > or =9 g/dL or lower erythropoietin levels have demonstrated better responses to epoetin beta than other patients in clinical trials. However, neither baseline erythropoietin level nor the observed to predicted ratio of erythropoietin levels correlated with the response to epoetin beta in patients with solid tumours and chemotherapy-induced anaemia. A decrease of <1 g/dL or an increase in Hb with epoetin beta during the first chemotherapy cycle indicated a low transfusion need in subsequent cycles in patients with ovarian carcinoma. In general, the efficacy of epoetin beta is not limited by tumour type. Response to the drug occurred irrespective of the nature (platinum- or nonplatinum-based) or presence of chemotherapy treatment in randomised trials. CONCLUSION: Epoetin beta has shown efficacy in the management of cancer-related anaemia in patients with haematological malignancies and of chemotherapy-induced anaemia in patients with solid tumours. Once-weekly administration provides added convenience for patients and may be cost saving, although additional research into the potential pharmacoeconomic benefits of this regimen are required. The drug is well tolerated in patients with cancer and is associated with little injection-site pain when administered subcutaneously. Epoetin beta is an important option in the prevention of chemotherapy-induced anaemia, and a valid and valuable alternative to blood transfusion therapy for the treatment of cancer-related or chemotherapy-induced anaemia.  相似文献   
108.
Exploring means to maintain or improve immunity in older persons has been receiving attention. To establish relationships between immune function and variables of interest, it is important to determine these variables accurately and precisely. Precision relates to the degree of variation in the laboratory test. The nature and magnitude of variability in tests of immune function has not been described extensively. We examined inter- and intra-individual variation in tests of cell-mediated immunity (CMI) in generally healthy and well-nourished young (20-40 years; n=15) and old (60-80 years; n=15) women. Subjects provided blood samples on 2 days within a week to determine leukocyte subsets, T-cell proliferation response to phytohemagglutinin A and concanavalin A, and interleukin (IL)-1beta, IL-2 and IL-6 production by stimulated mononuclear cells. Intra-individual variation was partitioned into day-to-day biological and analytical variation. Inter-individual variation was greater than intra-individual variability for most tests of CMI for both age groups. Furthermore, all CMI tests exhibited large day-to-day intra-individual variation (CV approximately 15% or greater) which was primarily due to biological rather than analytical sources, for both age groups. In conclusion, both age groups showed large between-person and considerable within-person variation in CMI tests. Therefore, assessment of CMI based on a single blood draw may not provide a reliable estimate of immune function.  相似文献   
109.
110.
Cochlear endolymph is maintained at a potential of (+)80 mV by an active transport mechanism involving the stria vascularis (SV). This so-called endocochlear potential (EP) is integral to hair cell transduction. We compared the EP with changes in SV area and Na(+),K(+)-ATPase expression following a sensorineural hearing loss. Guinea pigs were deafened using kanamycin and a loop diuretic, and the EP was measured at two, 14, 56, 112 or 224 days following deafening. Auditory brainstem responses were used to confirm that each animal had a severe-profound hearing loss. There was a significant reduction in EP following two days of deafness (normal, 73.5 mV S.E.M.=2.4; deaf, 42.1 mV, S.E.M.=2.8; P<0.0001, t-test). In animals deafened for 14 days the EP had partially recovered (65.2 mV, S.E.M.=5.08), while animals deafened for longer periods exhibited a complete recovery (56 days 80.5 mV, S.E.M.=5.36; 112 days 75.7 mV, S.E.M.=2.71; 224 days 81.0 mV; S.E.M.=6.0). Despite this recovery, there was a systematic reduction in SV area with duration of deafness over the first 112 days of deafness. Significant reductions were localised to the basal turn in animals deafened for two days, but had extended to all turns in animals deafened for 112 days. While there was a significant reduction in strial area, the optical density of Na(+),K(+)-ATPase within the remaining SV was normal. Since the treated animals exhibited essentially a complete elimination of all hair cells, the total K(+) leakage current from the scala media would be expected to be significantly reduced. The large reduction in the extent of the SV after deafening suggests that a reduced strial volume is capable of maintaining a normal EP under conditions of reduced K(+) leakage current.  相似文献   
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