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71.
Assessment of radiologic progression in rheumatoid arthritis. A randomized, controlled trial 总被引:5,自引:0,他引:5
J F Fries D A Bloch J T Sharp D J McShane P Spitz G B Bluhm D Forrester H Genant P Gofton S Richman 《Arthritis and rheumatism》1986,29(1):1-9
Radiologic assessment of progressive joint destruction in rheumatoid arthritis is generally considered to be the ultimate standard for evaluation of treatment. We compared alternative radiologic techniques by performing a randomized, controlled trial in which hand films of rheumatoid arthritis patients were read by several skilled observes. The number of joints evaluated (34 versus 18) was found to make relatively little difference, but the number of readers and their experience level was critical. Films should be read in pairs. Joint space narrowing and erosion scores were shown to contribute independent information. Use of recommended techniques can reduce the number of patients required and, thus, can reduce the cost of a clinical trial by more than half and can substantially increase the sensitivity and efficiency of a trial. Therefore, critical selection of the method of assessing study endpoint is of great importance. 相似文献
72.
Anne Brücken Pinar Kurnaz Christian Bleilevens Matthias Derwall Joachim Weis Kay Nolte Rolf Rossaint Michael Fries 《Resuscitation》2014
Purpose
Argon at a dosage of 70% is neuroprotective when given 1 h after cardiac arrest (CA) in rats. In a rodent model, we investigated if the neuroprotective effects of argon are dose dependent and mediated by adenosine triphosphate dependent potassium (KATP) channels.Methods
Forty-seven male Sprague-Dawley rats were subjected to 7 min of CA and 3 min of cardiopulmonary resuscitation (CPR). In protocol I animals were randomized to receive either 70% or 40% argon ventilation 1 h after successful CPR or no argon-treatment. Animals of the second protocol also received 1 h of 70% argon ventilation or no argon treatment but were randomized to a group receiving the KATP channel blocker 5-hydroxydecanoate (5-HD). For all animals a neurological deficit score (NDS) was calculated daily for seven days following the experiment before the animals were killed and the brains harvested for histopathological analyses.Results
All animals survived. Control animals exhibited severe neurologic dysfunction at all points in time as measured with the NDS. Argon treated animals showed significant improvements in the NDS through all postoperative days in a dose dependent fashion. This was paralleled by a significant reduction in the neuronal damage index in the neocortex and the hippocampal CA 3/4 region. Administration of 5-HD neither abolished the positive effects on functional recovery nor on histopathologic changes observed in the argon group.Conclusion
Our study demonstrates a dose dependent neuroprotective effect of argon administration in this rodent model, which is not mediated via ATP dependent potassium channels. 相似文献73.
Ohne ZusammenfassungHierzu Taf. XIV. 相似文献
74.
Marietta Garmer Julia Karpienski Dietrich HW Groenemeyer Birgit Wagener Lars Kamper Patrick Haage 《The British journal of radiology》2022,95(1131)
Objectives:To evaluate the efficiency of structured reporting in radiologic education – based on the example of different PI-RADS score versions for multiparametric MRI (mpMRI) of the prostate.Methods:MpMRI of 688 prostate lesions in 180 patients were retrospectively reviewed by an experienced radiologist and by a student using PI-RADS V1 and V2. Data sets were reviewed for changes according to PI-RADS V2.1. The results were correlated with results obtained by MR-guided biopsy. Diagnostic potency was evaluated by ROC analysis. Sensitivity, specificity and correct-graded samples were evaluated for different cutpoints. The agreement between radiologist and student was determined for the aggregation of the PI-RADS score in three categories. The student’s time needed for evaluation was measured.Results:The area under curve of the ROC analysis was 0.782/0.788 (V1/V2) for the student and 0.841/0.833 (V1/V2) for the radiologist. The agreement between student and radiologist showed a Cohen‘s weighted κ coefficient of 0.495 for V1 and 0.518 for V2. Median student’s time needed for score assessment was 4:34 min for PI-RADSv1 and 2:00 min for PI-RADSv2 (p < 0.001). Re-evaluation for V2.1 changed the category in 1.4% of all ratings.Conclusion:The capacity of prostate cancer detection using PI-RADS V1 and V2 is dependent on the reader‘s experience. The results from the two observers indicate that structured reporting using PI-RADS and, controlled by histopathology, can be a valuable and quantifiable tool in students‘ or residents’ education. Herein, V2 was superior to V1 in terms of inter-observer agreement and time efficacy.Advances in knowledge:Structured reporting can be a valuable and quantifiable tool in radiologic education. Structured reporting using PI-RADS can be used by a student with good performance. PI-RADS V2 is superior to V1 in terms of inter-observer agreement and time efficacy. 相似文献
75.
76.
HW Schytz T Wienecke PS Oturai J Olesen & M Ashina 《Cephalalgia : an international journal of headache》2009,29(2):258-268
The parasympathetic nervous system is likely to be involved in migraine pathogenesis. We hypothesized that the cholinomimetic agonist carbachol would induce headache and vasodilation of cephalic and radial arteries. Carbachol (3 µg/kg) or placebo was randomly infused into 12 healthy subjects in a double-blind crossover study. Headache was scored on a verbal rating scale from 0–10. Velocity in the middle cerebral artery (VMCA ) and diameter of the superficial temporal artery (STA) and radial artery (RA) were recorded. Nine participants developed headache after carbachol compared with three after placebo. The area under the curve for headache was increased after carbachol compared with placebo both during infusion (0–30 min) ( P = 0.042) and in the postinfusion period (30–90 min) ( P = 0.027). Carbachol infusion caused a drop in VMCA ( P = 0.003) and an increase in STA diameter ( P = 0.006), but no increase in the RA diameter ( P = 0.200). In conclusion, the study demonstrated that carbachol caused headache and dilation of cephalic arteries in healthy subjects. 相似文献
77.
OBJECTIVE: Duration of therapy has been suggested to represent a measure of effectiveness. Life table analyses of therapy with methotrexate (MTX) in rheumatoid arthritis (RA) have indicated a longer duration than with other drugs. However, individual patients continue taking MTX for different periods of time. We assessed the influence of patient variables at treatment onset upon subsequent duration of MTX therapy. METHODS: Patients with RA (n = 437) from 8 North American databank centers beginning MTX therapy after January 1, 1988, were followed prospectively. Age at onset of MTX treatment, sex, years of education, age at onset of disease, years with disease, number of comorbid conditions, number of disease modifying antirheumatic drugs (DMARD) and nonsteroidal antiinflammatory drugs (NSAID) taken just prior to MTX. disability level, pain, and global assessment prior to starting MTX were used in univariate Kaplan-Meier analyses to predict number of months taking MTX alone. An index that divided the patients into risk strata for predicting duration of therapy was constructed to be clinically useful. RESULTS: The median number of months continuing MTX without addition of other DMARD was 41 months and the median for the total course taking MTX was 52 months. The retention rate was lowest for patients with the most negative initial health state. High level of initial pain, long duration of disease, and not using a DMARD just prior to MTX were associated with low retention rate and can be used to predict expected durations of MTX treatment ranging from 17 to 52 months. For practical guidance in clinical decisions an index was computed based on the predictor variables: level of initial pain, duration of disease, and number of DMARD; this index identifies subgroups with very different durations taking MTX alone. Disease duration at baseline was strongly related to time taking MTX alone and could therefore also be used as a simplified rule in clinical work. CONCLUSION: Expected duration of MTX treatment is influenced by clinical variables, and these may suggest those patients likely to have more or less satisfactory experiences with MTX. The time taking drug alone (therapeutic segment) may be a more logical and sensitive indicator of effectiveness than the total course on the medication. 相似文献
78.
Lêda S. Garcia Clarissa M. Comim Samira S. Valvassori Gislaine Z. Réus Ana Cristina Andreazza Laura Stertz Gabriel R. Fries Elaine Cristina Gavioli Flavio Kapczinski João Quevedo 《Basic & clinical pharmacology & toxicology》2008,103(6):502-506
Abstract: A growing body of evidence has pointed to the blockade of the N‐methyl‐d ‐aspartate (NMDA) receptor signaling as a potential therapeutic target for the treatment of major depression. The present study was aimed to evaluate behavioural and molecular effects of the chronic treatment with ketamine and imipramine in rats. To this aim, rats were 14 days treated once a day with ketamine (5, 10 and 15 mg/kg) and imipramine (10, 20 and 30 mg/kg) and then subjected to the forced swimming and open‐field tests. Ketamine and imipramine, at the all doses tested, reduced immobility time, and increased both climbing and swimming time of rats compared to the saline group, without affecting spontaneous locomotor activity. Brain‐derived neurotrophic factor (BDNF) hippocampal levels were assessed in imipramine‐ and ketamine‐treated rats by ELISA sandwich assay. Chronic administration of both drugs, ketamine and imipramine, did not modify BDNF protein levels in the rat hippocampus. In conclusion, our findings demonstrate for the first time that chronic administration of acute inactive doses of ketamine (5 mg/kg) becomes active after chronic treatment, while no signs of tolerance to the behavioural effects of ketamine were observed after chronic administration of acute active doses (10 and 15 mg/kg). Finally, these findings further support the hypothesis that NMDA receptor could be a new pharmacological target for the treatment of mood disorders. 相似文献
79.
Background
Whole body vibration (WBV) exposure at work is common and studies found evidence that this exposure might cause low back pain (LBP). A recent review concluded there is a lack of evidence of effective strategies to reduce WBV exposure. Most research in this field is focussed on the technical implications, although changing behaviour towards WBV exposure might be promising as well. Therefore, we developed an intervention programme to reduce WBV exposure in a population of drivers with the emphasis on a change in behaviour of driver and employer. The hypothesis is that an effective reduction in WBV exposure, in time, will lead to a reduction in LBP as WBV exposure is a proxy for an increased risk of LBP. 相似文献80.
Evidence of zoonotic transmission of Cryptococcus neoformans from a pet cockatoo to an immunocompromised patient 总被引:4,自引:0,他引:4
Nosanchuk JD Shoham S Fries BC Shapiro DS Levitz SM Casadevall A 《Annals of internal medicine》2000,132(3):205-208
BACKGROUND: Although cryptococcosis has been associated with birds for almost 50 years, point sources for infection have not been identified. OBJECTIVE: To document zoonotic transmission of Cryptococcus neoformans. DESIGN: Case report. SETTING: A home in Boston, Massachusetts. PATIENT: A 72-year-old woman who received a diagnosis of cryptococcal meningitis in November 1998. The patient, who had been taking immunosuppressant drugs since undergoing renal transplantation in 1989, owned a pet cockatoo. MEASUREMENTS: Cryptococcus neoformans was isolated from the feces of the cockatoo. Isolates from excreta and from the patient were compared by using biochemical profiles, monoclonal antibody binding patterns, restriction fragment length polymorphism analysis, and karyotyping. RESULTS: The isolates from the patient and the cockatoo had identical biochemical profiles, the same monoclonal antibody immunofluorescence patterns, and indistinguishable patterns on restriction fragment length polymorphism analysis and karyotyping. CONCLUSIONS: The indistinguishable patient and cockatoo isolates strongly suggest that the patient's infection resulted from exposure to aerosolized cockatoo excreta. Although the incidence of cryptococcal infection due to such exposure is unknown, it may be prudent to advise immunocompromised patients to avoid pet birds and avian excreta. 相似文献