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61.
Background and Rationale:
Ensuring research participants’ autonomy is one of the core ethical obligations of researchers. This fundamental principle confers on every participant the right to refuse to take part in clinical research, and the measure of the number of consent refusals could be an important metric to evaluate the quality of the informed consent process. This audit examined consent refusals among Indian participants in clinical studies done at our center.Materials and Methods:
The number of consent refusals and their reasons in 10 studies done at our center over a 5-year period were assessed. The studies were classified by the authors according to the type of participant (healthy vs patients), type of sponsor (investigator-initiated vs pharmaceutical industry), type of study (observational vs interventional), level of risk [based on the Indian Council of Medical Research (ICMR) “Ethical Guidelines for Biomedical Research on Human Participants”], available knowledge of the intervention being studied, and each patient''s disease condition.Results:
The overall consent refusal rate was 21%. This rate was higher among patient participants [23.8% vs. healthy people (14.9%); P = 0.002], in interventional studies [33.6% vs observational studies (7.5%); P < 0.0001], in pharmaceutical industry-sponsored studies [34.7% vs investigator-initiated studies (7.2%); P < 0.0001], and in studies with greater risk (P < 0.0001). The most common reasons for consent refusals were multiple blood collections (28%), inability to comply with the study protocol (20%), and the risks involved (20%).Conclusion:
Our audit suggests the adequacy and reasonable quality of the informed consent process using consent refusals as a metric.KEY WORDS: Autonomy, consent, India, reason, refusal, risk 相似文献62.
63.
Katsoulis K Kontakiotis T Baltopoulos G Kotsovili A Legakis IN 《Respiration; international review of thoracic diseases》2005,72(4):381-387
BACKGROUND: Oxidant/antioxidant imbalance has been reported in various respiratory diseases including pneumonia. However, the role of blood antioxidants has not been fully discussed. OBJECTIVES: The aim of this exploratory study was to assess serum total antioxidant status (TAS) in patients with community-acquired pneumonia (CAP) and the probable correlation with the severity of the disease. METHODS: Thirty patients (22 men, 8 women; mean age of 48 +/- 21 years) and 10 healthy nonsmokers (mean age 44 +/- 16 years) were studied. Clinical, laboratory and radiological findings were recorded on the day of admission and on the 7th day. A severity score was calculated using the Fine scale. Serum TAS was measured at the same time points using a colorimetric method. RESULTS: On admission, TAS (TAS1) was significantly lower than on the 7th day (TAS2) (0.84 +/- 0.13 mmo/l vs. 1.00 +/- 0.17 mmo/l; p = 0.0001) and compared with the healthy subjects (0.84 +/- 0.13 vs. 1.19 +/- 0.09 mmol/l; p < 0.001). TAS change (TAS2 - TAS1) was statistically significantly more marked in smokers (0.17 vs. 0.28, p = 0.001), in patients with factors predisposing to CAP (0.12 vs. 0.37; p = 0.000) and in patients with gram-negative pneumonia (0.16 vs. 0.35; p = 0.000). On the other hand, change in TAS was statistically significantly less marked in patients with lobar pneumonia (0.27 vs. 0.17; p = 0.001). Additionally, TAS change was positively correlated to white blood count on admission (r = 0.39; p = 0.029). CONCLUSIONS: It is concluded that serum TAS is decreased in patients with CAP, suggesting the presence of oxidative stress, and that change in TAS seems to be influenced by disease severity. TAS measurement may be useful in estimating the severity of CAP and is a probable indication for the administration of antioxidants in the management of the disease. 相似文献
64.
A nested, multiplex, PCR assay for the simultaneous detection and differentiation of Entamoeba histolytica and Entamoeba dispar in faeces 总被引:2,自引:0,他引:2
Evangelopoulos A Spanakos G Patsoula E Vakalis N Legakis N 《Annals of tropical medicine and parasitology》2000,94(3):233-240
The detection of and differentiation between Entamoeba histolytica and Entamoeba dispar are of great importance, both for diagnosis and for epidemiological studies. Most PCR-based methods for the discrimination of these two species employ complex procedures for DNA extraction and require different protocols for E. histolytica and E. dispar, leading to relatively high expenditure, labour costs and turnaround times. A simple, rapid, cost-effective and yet sensitive and specific multiplex PCR technique has now been developed for the simultaneous detection and differentiation of E. histolytica and E. dispar in faecal samples. The detection limit is 200 trophozoites of E. dispar or 1000 trophozoites of E. histolytica/g stool sample. The sensitivity of the assay remains practically unchanged, even in the presence of 20,000 trophozoites of the other species/g stool sample. Thus, this technique may also easily reveal mixed infections, without the danger of misdiagnosis caused by one strain displacing the other in culture. 相似文献
65.
Hall RM; Unsworth A; Wroblewski BM; Siney P; Powell NJ 《Rheumatology (Oxford, England)》1997,36(1):20-26
Charnley prostheses, retrieved at revision surgery, were studied to assess
the effects of friction on the total hip replacement procedure. Frictional
resistance was measured using the Durham hip function simulator under both
dry and lubricated conditions. The friction factor values (f) for the
explanted prostheses were found to have a non- Gaussian distribution with
medians of 0.13 [inter-quartile range (IQR) 0.10-0.16] and 0.06 (IQR
0.005-0.08) for dry and lubricated (n = 0.01 Pa s) regimes, respectively.
New Charnley prostheses had values of f equal to 0.11 +/- 0.025 and 0.04
+/- 0.01 under the same conditions, and showed no large deviation from a
Gaussian distribution. There was found to be a statistically significant
difference in the medians of the friction factors for new and retrieved
prostheses in the lubricated regime. Ingression of cement into the worn
region of the cup was found to increase the friction factor significantly
under dry conditions. There was no evidence of an increase in the friction
factor or torque for those joints that had a loose socket with respect to
those that were fixed at revision. A decrease in the frictional torque
against number of cycles undergone by the joint in vivo may indicate that a
fatigue-type process may have a role in the loosening of the socket.
However, this relationship was found not to be significant for friction
measured under lubricated conditions and it seems unlikely that the
frictional torque generated in this type of prosthesis will contribute
significantly to the long-term loosening of the socket.
相似文献
66.
Snyder DS; Negrin RS; O'Donnell MR; Chao NJ; Amylon MD; Long GD; Nademanee AP; Stein AS; Parker PM; Smith EP 《Blood》1994,84(5):1672-1679
Ninety-four consecutive patients with chronic myelogenous leukemia in first clinical chronic phase, median age of 34.0 years (range, 6.8 to 52.4 years), with a histocompatible sibling donor, were treated with fractionated total body irradiation (1,320 cGy) and high-dose etoposide (60 mg/kg) followed by allogeneic bone marrow transplantation (BMT). The median time from diagnosis to BMT was 7.0 months (range, 2.3 to 72.0 months). Sixty patients were treated before BMT with hydroxyurea alone, four patients with busulfan alone, one patient with interferon alone, and the other 29 patients were treated with various combinations of these drugs. Cumulative probabilities of overall survival, event- free survival, and relapse at 5 years were 73%, 64%, and 14%, respectively. The median follow-up time for surviving patients was 38 months, ranging from 12 to 88 months. By stepwise Cox regression analysis, significant prognostic variables were age at transplant, acute graft-versus-host disease > or = grade II, cytomegalovirus- associated interstitial pneumonitis, and years from diagnosis to BMT. 相似文献
67.
Rokey R; Verani MS; Bolli R; Kuo LC; Ford JJ; Wendt RE; Schneiders NJ; Bryan RN; Roberts R 《Radiology》1986,158(3):771-774
The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium. 相似文献
68.
69.
70.
Since the NHS reforms, health authorities have been purchasing health care and have been advised that publichealth considerations must inform all NHS activities, and that the Director of Public Health must be supported by a team of qualified support staff. This survey of directors of public health and health authority chief executives in England shows the skills currently available to support health authority purchasing, and the perceived importance of this wide range of skills to the purchasing process. Future models of purchasing will need to ensure access by purchasers to public health and multi-disciplinary advice. 相似文献