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21.
The present study investigated the perception of sweetness of aspartame in comparison to various concentrations of sucrose. Twenty-seven subjects were randomly assigned to taste a chilled or room temperature Kool-Aid beverage sweetened with either aspartame or five different concentrations of sucrose. Subjects assessed the perceived similarity in sweetness of an aspartame-aspartame pair and five different aspartame-sucrose pairings and rated each beverage on five bipolar adjectives. Analysis of the similarity ratings revealed that subjects did not perceive the pairs of beverages to differ in perceived sweetness. Analysis of the adjective ratings revealed that aspartame and the lower sucrose concentrations were perceived as being less sweet and more sour than the higher sucrose concentrations.  相似文献   
22.
Experience with the P.A.S.-PORT, a peripherally implanted central venous access device, is evaluated in a retrospective review of 154 patients from July 1991 to June 1994. Blood could not be aspirated from six patients. Complications included temporary minor thrombophlebitis in seven patients (4.5%), symptomatic axillary or subclavian vein thrombosis in five patients (3.2%), clotted port in two patients (1.2%), port pocket cellulitis in two patients (1.2%), and fungal sepsis in two patients (1.2%). In six patients (3.8%) the P.A.S.-PORT had to be removed because of complications. The P.A.S.-PORT facilitated delivery of chemotherapy, parenteral nutrition, blood products, antibiotics, hydration, and blood sampling. It was demonstrated that the P.A.S.-PORT may be inserted and used with a low incidence of complications in gynecologic cancer patients.  相似文献   
23.
AIMS: The developing world is particularly at risk of an increasing health burden due to an increased prevalence of Chronic Obstructive Pulmonary Disease (COPD) secondary to increasing tobacco consumption. However, research is scarce. The objectives of this study were to assess the current competence for diagnosing COPD in primary care in a resource-limited setting in Brazil, and to develop a local patient profile for case-finding. METHODS: 34 general practitioners (GPs) in five areas of northern Brazil recruited adult patients with principal complaints of cough and/or shortness of breath who then had spirometry (n = 142). RESULTS: For the dichotomous variable 'COPD' the degree of agreement between GP diagnosis (n = 64, 18.3%) and spirometric outcome (n = 36, 25.4%) was poor, with Kappa = 0.055 (SE 0.087) and DOR = 1.35. False-positive and false-negative diagnosis proportions were 19.8% and 75%, respectively. Independent risk factors were 'smoking history of more than five pack years' and 'presence of both dyspnoea and cough'. It requires the testing of 2.2 smokers with more than five pack years to detect one patient at risk. CONCLUSIONS: COPD is a common yet underdiagnosed disease in Brazilian primary care. Spirometry improves diagnostic competence and case-finding substantially. If applied in a pre-selected high-risk population, we believe spirometry can be a cost-effective diagnostic tool for case-finding in the resource-limited setting. This study provides important baseline information for effective guideline implementation.  相似文献   
24.
BACKGROUND: Somatisation is highly prevalent in primary care (present in 25% of visiting patients) but often goes unrecognised. Non-recognition may lead to ineffective treatment, risk of iatrogenic harm, and excessive use of healthcare services. AIM: To examine the effect of training on diagnosis of somatisation in routine clinical practice by general practitioners (GPs). DESIGN OF STUDY: Cluster randomised controlled trial, with practices as the randomisation unit. SETTING: Twenty-seven general practices (with a total of 43 GPs) in Vejle County, Denmark. METHOD: Intervention consisted of a multifaceted training programme (the TERM [The Extended Reattribution and Management] model). Patients were enrolled consecutively over a period of 13 working days. Psychiatric morbidity was assessed by means of a screening questionnaire. GPs categorised their diagnoses in another questionnaire. The primary outcome was GP diagnosis of somatisation and agreement with the screening questionnaire. RESULTS: GPs diagnosed somatisation less frequently than had previously been observed, but there was substantial variation between GPs. The difference between groups in the number of diagnoses of somatisation failed to reach the 5% significance (P = 0.094). However, the rate of diagnoses of medically unexplained physical symptoms was twice as high in the intervention group as in the control group (7.7% and 3.9%, respectively, P = 0.007). Examination of the agreement between GPs' diagnoses and the screening questionnaire revealed no significant difference between groups. CONCLUSION: Brief training increased GPs' awareness of medically unexplained physical symptoms. Diagnostic accuracy according to a screening questionnaire remained unaffected but was difficult to evaluate, as there is no agreement on a gold standard for somatisation in general practice.  相似文献   
25.
In 10 patients subjected to craniotomy for supratentorial cerebral tumours in neurolept anaesthesia, cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) were measured twice peroperatively by a modification of the Kety & Schmidt technique, using 133Xe. The relative CO2 reactivity was assessed indirectly as the % change of the arteriovenous oxygen difference (AVDO2) per mm change in PaCO2. The patients were premedicated with diazepam 10-15 mg perorally. For induction, thiopentone 4-6 mg/kg, droperidol 0.2 mg/kg and fentanyl 5 micrograms/kg were used, and for maintenance N2O 67% and fentanyl 4 micrograms/kg/h. During the first flow measurement the median and range of CBF was 30 ml/100 g/min (range 17-45), of AVDO2 8.0 vol % (range 4.1-9.5), and of CMRO2 2.28 ml O2/100 g/min (range 1.57-2.84). During the second CBF study, AVDO2 increased to 9.3 vol % (range 3.4-11) (P less than 0.05), and CMRO2 increased to 2.51 ml O2/100 g/min (range 1.88-3.00) P less than 0.05, while CBF was unchanged. The CO2 reactivity was present in all studies, median 1.8%/mmHg (range 0.5-15.1). The correlation coefficients between jugular venous oxygen tension/saturation, respectively, and CBF were high at tensions/saturations exceeding 4.0 kPa and 55%, indicating that hyperperfusion is easily unveiled by venous samples from the jugular vein during this anaesthesia.  相似文献   
26.
Studies of post-lesional reorganization of central nervous connections have shown that central nerve fibers respond to nearby denervation by sprouting and formation of new terminals. The connections in the central nervous system (CNS) are accordingly much more plastic than was thought for a long time. This has revived the interest in transplantation of central nervous tissue. In this study we present some historical data on CNS transplantation supplemented by recent results obtained in our laboratory. Pieces of hippocampal tissue from embryonic or early postnatal rats were transplanted to different parts of the brain of littermates or adult rats. About two-thirds of the transplants were recovered after survival times ranging from 4 d to 2 years, and their cytological organization and intrinsic connections were monitored by cell and fiber stains and histochemical methods (AChE staining and Timm sulphide silver method). Comparison with both a normal and a lesioned control material revealed that in most transplants the tissue had developed as it does when left in situ in the donor brain, but deprived of its major afferent connections. In several instances we found evidence of a major exchange of connections between the transplants and host brains. The conditions needed for this to occur appeared to involve growth stimulation of host brain fibers by transection (host to transplant) and denervation of host neuropil (transplant to host). In cases where these conditions are met, the use of transplants may have future implications in attempts to repair lesions in the central nervous systems.  相似文献   
27.
This study presents an analysis on longitudinal tumour marker series in twenty-two patients with non-seminomatous germ cell cancers treated with cisplatinum (DDP) based combination chemotherapy. Series of alphafoetoprotein (AFP), human chorionic gonadotropin (HCG) and lactate dehydrogenase (LDH) were analyzed applying a dynamic mathematical marker model. The model analysis provided quantitated values for growth rate and treatment response in the marker producing cells. The analysis showed that LDH had to be above 2 000 U/l to be a trustworthy tumour marker. HCG producing cells tended to grow faster than AFP producing cells, and were 3-5-fold more sensitive to the chemotherapy given than AFP producing cells. Treatment response versus DDP dose appeared to be bi-phasic, but with no significant change in treatment efficiency within the given range of DDP doses.  相似文献   
28.
Ectopic bone formation after total hip arthroplasty   总被引:2,自引:0,他引:2  
Ectopic bone formation (EBF) is a well-known complication of total hip arthroplasty (THA). The etiology and pathogenesis are still obscure. An analysis of 119 consecutive patients with 129 primary THAs was performed to identify factors predisposing to ectopic bone formation, its frequency, and its effect on the results. Gender (male) and the duration of the operative procedure were statistically significant factors in the development of ectopic bone, which occurred in 63% of hips. The effect of grade III EBF on THA was a limited range of movement. Both local and systemic factors seem to play a role in the development of ectopic bone. Gentle handling of tissues may be important if the rate of ectopic bone is to be reduced.  相似文献   
29.
SETTING: In 10 healthy subjects, the influence of acute alcohol intake on the pharmacokinetics of isoniazid (INH) was studied. OBJECTIVE: To test the hypothesis that alcohol increases the conversion of INH by acetylation into its metabolite acetylisoniazid. DESIGN: In a crossover design, an oral dose of 300 mg INH was administered on 2 separate days, 14 days apart, with or without alcohol to a serum alcohol of about 21 mmol/l (1 g/l) maintained for 12 h. RESULTS: Neither the metabolism of INH nor that of acetylisoniazid was changed by acute alcohol intake. CONCLUSION: Acute alcohol intake has no impact on the conversion of INH to its metabolite acetylisoniazid, which is catalysed by the enzyme N-acetyltranferase. Accordingly, a metabolic effect of acute alcohol intake on INH metabolism probably contributes little to the therapeutic failure of anti-tuberculosis treatment among alcoholics.  相似文献   
30.
Introduction - Interobserver variation among four observers in evaluation of eight selected neurological signs was investigated. Material & methods - Two hundred and two consecutive unselected inpatients were examined by two senior neurologists and two trainees, all without knowledge of the neurological case history. The signs examined were: anisocoria, jerky eye movements, facial palsy, elbow extension force, finger-nose test, Barré sign, knee jerk, and extensor plantar reflex. Observed agreement rates and kappa coefficients were calculated in order to compare the interobserver variability among neurologists and trainees, and to evaluate differences in the interobserver variability between signs. Results - Observed agreement rates varied from 0.80 to 0.95 for neurologists and from 0.65 to 0.98 for trainees. For neurologists kappa coefficients ranged from 0.40 to 0.67 and for trainees from 0.22 to 0.81. The neurologists had higher kappa values than the trainees in 5 signs, but this difference was only statistically significant for jerky eye movements. For the individual signs the observed agreement rates were between 0.50 and 0.93 for all four examiners combined, and overall kappa values varied from 0.32 to 0.71 with highest agreement for facial palsy and lowest for knee jerk. Conclusion - The magnitude of the interobserver and intersign variation indicates that the interpretation of the neurological signs tested, without knowledge of the case history, should be done with some caution.  相似文献   
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