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91.

OBJECTIVE

To determine to what extent urologists with no specific training agree upon level of evidence (LoE) ratings of studies published in the urological literature, as LoE are commonly referenced as a measure of evidence quality.

MATERIALS AND METHODS

In all, 86 clinical research studies published in four major urology journals were reviewed. Each article was independently reviewed by eight reviewers using a standardized data abstraction form. Articles were assessed for type of study (therapy, prognosis, diagnosis or economic) and LoE (I, II, III or IV). Reviewers received only written instructions and no formal training in the application of this classification system.

RESULTS

Of the 86 articles, 69% related to therapy, 16% to prognosis, and 15% to diagnosis. Eight studies (9%) provided Level I evidence, 18 studies (21%) Level II, 14 studies (16%) Level III and 46 studies (54%) Level IV evidence. The intraclass correlation coefficient (95% confidence interval) based on all reviewers (eight reviewers) was 0.67 (0.59–0.74; P= 0.001) for the type of study and 0.55 (0.48–0.64; P= 0.001) for the LoE. In an analysis limited to a subset of studies in which all reviewers agreed upon the type of study question (n= 40) the intraclass correlation coefficient was 0.79 (0.70–0.86; P= 0.001).

CONCLUSION

In the present study there was a low interobserver agreement for LoE ratings by urologists with no specific training. These findings suggest caution in the interpretation of LoE ratings and emphasize the importance of specific training for individuals that are charged with quality of evidence determinations.  相似文献   
92.
93.
Extremely low frequency electro magnetic fields (EMFs) have been classified as possibly carcinogenic to humans by the International Agency for Research on Cancer. An increased number of chromosomal alterations in peripheral lymphocytes are correlated with elevated incidence of cancer. The aim of the present study was to assess occupationally induced chromosomal damage in EMF workers exposed to low levels of radiation. We used conventional metaphase chromosome aberration (CA) analysis and the micronucleus (MN) assay as biological indicators of non ionizing radiation exposure. In the present study totally 70 subjects were selected including 50 exposed and 20 controls. Informed written consent was obtained from all participants and the study was performed in accordance with the Declaration of Helsinki and the approval of the local ethical committee. A higher degree of CA and MN was observed in exposed subjects compared to controls, the frequency of CA being significantly enhanced with long years of exposure (P<0.05). Moreover increase in CA and MN with age was noted in both exposed subjects and controls, but was significantly greater in the former. The results of this study demonstrated that a significant induction of cytogenetic damage in peripheral lymphocytes of workers occupationally exposed to EMFs in electric transformer and distribution stations. In conclusion, our findings suggest that EMFs possess genotoxic capability, as measured by CA and MN assays; CA analysis appeared more sensitive than other cytogenetic end-points. It can be concluded that chronic occupational exposure to EMFs may lead to an increased risk of genetic damage among electrical workers.  相似文献   
94.
AIM:To introduce the combination method of radio-chemoembolization for the treatment of selected hepatic metastases. METHODS:Twenty patients with biopsy proven hepatic metastases were selected from those who underwent transarterial radiochemoembolization, a novel combination protocol, between January 2009 and July 2010. Patients had different sources of liver metastasis. The treatment included transarterial administration of three chemotherapeutic drugs (mitomycin, doxorubicin and cisplatin), followed by embolization with large (50-150 μm) radioisotope particles of chromic 32P. Multiphasiccomputer tomography or computer tomography studies, with and without contrast medium injections, were performed for all patients for a short-term period before and after the treatment sessions. The short-term effec-tiveness of this procedure was evaluated by modified response evaluation criteria in solid tumors (mRECIST), which also takes necrosis into account. The subjective percentage of necrosis was also assessed. The response evaluation methods were based on the changes in size, number, and the enhancement patterns of the lesions between the pre-and post-treatment imaging studies. RESULTS:Patients had liver metastasis from colorectal carcinomas, breast cancer, lung cancer and carcinoid tumors. The response rate based on the mRECIST criteria was 5% for complete response, 60% for partial response, 10% for stable disease, and 25% for progressive disease. Regarding the subjective necrosis percentage, 5% of patients had complete response, 50% had partial response, 25% had stable disease, and 20% had progressive disease. Based on traditional RECIST criteria, 3 patients (15%) had partial response, 13 patients (65%) had stable disease, and 4 patients (20%) had disease progression. In most patients, colorectal carcinoma was the source of metastasis (13 patients). Based on the mRECIST criteria, 8 out of these 13 patients had partial responses, while one remained stable, and 5 showed progressive disease. We also had 5 cases of breast cancer metastasis which mostly remained stable (4 cases), with only one partial response after the procedure. Six patients had bilobar involvement; three of them received two courses of radiochemoembolization. The follow up imaging study of these patients was performed after the second ses-sion. In the studied patients there was no evidence of extrahepatic occurrence, including pulmonary radioac-tive deposition, which was proven by Bremsstrahlung scintigraphy performed after the treatment sessions. For the short-term follow-ups for the 2 mo after the therapy, no treatment related death was reported. The mostly common side effect was post-embolizationsyndrome, presented as vomiting, abdominal pain, and fever. Nineteen (95%) patients experienced this syndrome in different severities. Two patient had ascites (with pleural effusion in one patient) not related to hepatic failure. Moreover, no cases of acute liver failure, hepatic infarction, hepatic abscess, biliary necrosis, tumor rupture, surgical cholecystitis, or non-targeted gut embolization were reported. Systemic toxicities such as alopecia, marrow suppression, renal toxicity, or cardiac failure did not occur in our study group. CONCLUSION:Radiochemoembolization is safe and effective for selected hepatic metastases in a short-term follow-up. Further studies are required to show the long-term effects and possible complications of this approach.  相似文献   
95.
GRADE requires guideline developers to make an overall rating of confidence in estimates of effect (quality of evidence—high, moderate, low, or very low) for each important or critical outcome. GRADE suggests, for each outcome, the initial separate consideration of five domains of reasons for rating down the confidence in effect estimates, thereby allowing systematic review authors and guideline developers to arrive at an outcome-specific rating of confidence. Although this rating system represents discrete steps on an ordinal scale, it is helpful to view confidence in estimates as a continuum, and the final rating of confidence may differ from that suggested by separate consideration of each domain.An overall rating of confidence in estimates of effect is only relevant in settings when recommendations are being made. In general, it is based on the critical outcome that provides the lowest confidence.  相似文献   
96.
97.

Purpose

In order to prevent postpartum hemorrhage in caesarean section under spinal anesthesia, patients routinely receive oxytocin. In this study we compared the efficacy of Methylergonovine and Oxytocin on hemodynamic stability and bleeding amount in caesarean section.

Materials and methods

In this randomised controlled trial study, 80 patients candidate for elective caesarean section under spinal anesthesia divided to two groups: 40 patients in control group received oxytocin and 40 ones in case group received methylergonovine.

Results

There was no differences between groups in Mean age, baseline hemodynamic values, after spinal anesthesia and recovery (except diastolic blood pressure min 20), time of uterine atony, dizziness; nausea and vomiting. After drug administration (oxytocin and methylergonovine), systolic blood pressure in minutes 1, 10, 15 and diastolic blood pressure in minutes 1, 3, 20 increased in case group statistically more than control group. In control group, heart rate in minutes 1, 5 increased significantly more than the other group. Mean arterial blood pressure in minutes 1, 3, 5, 10, 15 reduced significantly more than in control group. Need to vasoconstrictor drug statistically was less in case group (p < 0.0001).

Conclusion

Methylergonovine induced significantly more hemodynamic stability. Adverse effects were similar between two groups. We recommend the use of methylergonovine in patients with caesarean section under spinal anesthesia because of its hemodynamic stability and low need to vasoconstrictor drugs.  相似文献   
98.
99.
To elucidate the effect of cigarette smoke on developing lung cancer among individuals, numerous genetic and epigenetic factors related to cigarette smoke-induced lung cancers have been widely investigated and a various genes, loci and pathways have been identified as candidates to date. However, the importance of these molecular alterations in the initiation and progression of lung cancer still remains imprecise and different molecules altered in lung cancer are being used for stratification of patients for targeted therapy. There are a number of molecular pathways involved in the development of lung cancer, and environmental factors related to these alterations are still unclear. Furthermore, various genetic alterations determined by candidate gene approach have not been re-evaluated for their functional significance together with epigenetic alterations in the same population. Accumulated evidence suggested that lung cancer in ever smokers and never smokers follow distinct molecular pathways and may therefore respond to distinct therapy. Therefore, additional studies will be essential to re-evaluate the individual risk of developing lung cancer based on the combination of genetic and epigenetic alterations and to set up a guideline to assess the individual risk for lung cancer and for its prevention.  相似文献   
100.
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