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81.
This work aims to take stock of the actual utilisation of medical standards (references), through a study of opinions and practices of the medical managers working in the clinical services of a university hospital centre. A survey through interviews was proposed to 103 medical managers, 101 responded to the questionnaire (38 Unit directors and 63 directors of "UF" units). Medical standards are used essentially as a teaching aid by 80% of doctors. Some of them (48%) make them available to prescribing doctors in the unit, and for 36% there exists an informational procedure for new residents. Evaluation studies concerning the implementation of medical standards remain rare (7 studies). Medical standards appear to be more useful for improving quality of care (90%) then for controlling health expenditures (72%). The majority of medical managers (72%) consider that certain standards should be opposable to hospitals. The medical managers of the university hospital centre are in favour of developing standards of clinical practice.  相似文献   
82.
Within a given family of seven transmembrane domain (7TM) receptors, functional diversity is most often afforded by the existence of multiple receptor subtypes, each encoded by a distinct gene. However, it is now clear that the existence of introns in genes encoding some members of a receptor family provides scope for additional diversity by virtue of splicing events that result in the formation of different receptor mRNAs and consequently distinct receptor isoforms. A large number of 7TM receptor splice variants have now been shown to exist. In this article, the current data on alternatively spliced variants for hormone and neurotransmitter 7TMs are reviewed, their potential physiological importance considered and some of the issues pertaining to the classification and nomenclature of receptor isoforms produced in this way are addressed.  相似文献   
83.
Aneurysmal cysts of the mandible and maxilla are rare conditions, though not exceptional, which are seen in particular in the child and adolescent. A part from facial asymmetry and tumefaction, it is rare to find other clinical manifestations. No neurological signs were seen in the present study. An aneurysmal cyst gives a radiological appearance of non-characteristic lysis compatible with a large range of diagnoses. Histological study permits early diagnosis but must always involve the whole specimen with careful examination to detect any other associated lesion. The pathogenesis of the condition remains obscure and, at the extreme, it may be questioned whether the aneurysmal cyst is a separate entity or a particular form of chronic osteopathy.  相似文献   
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85.
Provocative tests for coronary spasm were performed in a groupof 131 patients (124 men and 7 women) with recent (<6 weeks)transmural myocardial infarction. Coronary arteriography wasperformed 27±9 days after the onset of the infarction.The provocative test was performed using a single IV bolus of0.4 mg of ergometrine. Aortic pressure, ECG and arteriogramsof the two coronary vessels were repeated 3 and 5 min later.Provoked spasm was observed in 27 (21%) of the patients. In13 (48%) the coronary spasm occurred in a vessel presumed tobe responsible for the myocardial infarction, while it was observedin coronary artery unrelated to the area of the infarct in 14(52% of the cases with spasm). Thus, this study demonstratesa high degree of reactivity of the coronary tree of patientswith recent transmural myocardial infarction suggesting thelikelihood of a role for spasm in the infarction process andoffering some explanation for subsequent recurrent ischemicevents.  相似文献   
86.
A patient operated upon 20 years ago for myocardial revascularization with two Vineberg procedures and one coronary artery bypass graft (CABG) on the right coronary artery had a recurrence of unstable angina due to the thrombosis of the left internal mammary artery (IMA) and the right CABG. The right IMA was patent but stenosed distally. Reoperation was performed with a direct end to side anastomosis of the patent right IMA onto the left anterior descending artery and a saphenous vein graft as a CABG on the marginal branch. We comment on the choice of this "second hand" IMA graft and the pathological appearances of the patent IMA.  相似文献   
87.
OBJECTIVES: To compare the results of the BTA Trak test with voided urine cytology (VUC) in the diagnosis and follow-up of bladder tumors. PATIENTS AND METHODS: Urine samples were obtained from 53 patients with bladder tumor (77 samples) and 53 patients treated for bladder tumor with no evidence of disease on the basis of cystoscopic evaluation (88 samples). Urine samples were collected prior to cystoscopy. The BTA assay was performed by the BTA Trak test according to the manufacturer's recommendations. A value >14 U/ml was considered abnormal. RESULTS: There was a statistically significant increase in median BTA value with increasing stage of tumor: 11.9, 57.9 and 391.0 U/ml respectively for stages pTa, pT1 and pT2/3 (p<0.0001, Kruskal-Wallis test). There was also a correlation between increasing grade and median BTA values measured at 6.9, 13.1 and 235.0 U/ml in grades 1, 2 and 3 tumors respectively (p<0.0001, Kruskall-Wallis test). The overall sensitivity of the BTA Trak test was 58.4% compared to 46.7% for VUC, a difference of 11.7%, which was statistically significant (McNemar test, p<0.005). The sensitivity of both tests combined was 63.6%. The specificity of the VUC (94.3%) was significantly higher than that of the BTA Traktrade mark (75.0%) (p<0.005, McNemar test). The accuracy of the Bard Trak test (67.3%) was similar to that of VUC (66.9%). CONCLUSION: The BTA Trak test is more sensitive than urinary cytology in the detection of bladder tumors but the improvement involved is insufficient to consider decreasing the frequency of endoscopic examinations in the follow-up of superficial bladder tumor.  相似文献   
88.
PURPOSE: Irofulven (6-hydroxymethylacylfulvene) is a novel agent, derived from illudin S, with potent apoptotic effects in preclinical models. In the Phase I trial evaluating intermittent weekly schedules, visual symptoms were dose limiting. The aim of this analysis was to better characterize the visual adverse events of irofulven and provide treatment guidelines. EXPERIMENTAL DESIGN: Clinical data from 277 patients entered in single-agent Phase I to II clinical trials who received irofulven on days 1 and 15 every 4 weeks; days 1, 8, and 15 every 4 weeks; or days 1 and 8 every 3 weeks were included in this multiparameter analysis. RESULTS: Overall, 74 patients (27%) experienced visual symptoms. The most frequently reported symptoms were flashing lights (12% of patients), blurred vision (9%), and photosensitivity (8%). Grade 3 toxicity was observed in 12 patients (4%). The incidence and severity of visual events were dose dependent, with no grade 3 visual events occurring at doses < or =0.50 mg/kg and grade 1 to 2 events in only 12% and 8% of patients, at doses of < or =0.50 mg/kg and < or =20 mg/m2, respectively. Grade 1 to 2 toxicity was reversible in most patients. Abnormal electroretinogram and abnormal visual fields were noted after irofulven treatment in 24 of 39 patients (62%) and 15 of 26 patients (58%), respectively. All but 1 patient who had electroretinogram assessment received doses >0.50 mg/kg. Clinical examination and visual field assessment were found to be better correlated with symptoms and appear to be more appropriate for surveillance of irofulven retinal symptoms than electroretinograms. CONCLUSIONS: On the basis of retained antitumor activity and reversibility of grade 1 and 2 visual symptoms at lower doses, it appears that an irofulven dose of < or =0.50 mg/kg or < or =20 mg/m2, not to exceed 50 mg in a single dose, given as a 30-minute infusion on days 1 and 8 every 3 weeks or days 1 and 15 every 4 weeks minimizes the frequency and severity of visual symptoms.  相似文献   
89.
90.
OBJECTIVE: To assess the impact of introducing clinical practice guidelines on acute coronary syndrome without persistent ST segment elevation (ACS) on patient initial assessment. DESIGN: Prospective before-after evaluation over a 3-month period. SETTING: The emergency ward of a tertiary teaching hospital. PATIENTS: All consecutive patients with ACS evaluated in the emergency ward over the two 3-month periods. INTERVENTION: Implementation of the practice guidelines, and the addition of a cardiology consultant to the emergency team. MAIN OUTCOME MEASURES: Diagnosis, electrocardiogram interpretation, and risk stratification after the initial evaluation. RESULTS: The clinical characteristics of the 328 and 364 patients evaluated in the emergency ward for suspicion of ACS before and after guideline implementation were similar. Significantly more patients were classified as suffering from atypical chest pain (39.6% versus 47.0%; P = 0.006) after guideline implementation. Guidelines availability was associated with significantly more formal diagnoses (79.9% versus 92.9%; P < 0.0001) and risk stratification (53.7% versus 65.4%, P < 0.0001) at the end of initial assessment. CONCLUSION: Guidelines implementation, along with availability of a cardiology consultant in the emergency room had a positive impact on initial assessment of patients evaluated for suspicion of ACS. It led to increased confidence in diagnosis and stratification by risk, which are the first steps in initiating effective treatment for this common condition.  相似文献   
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