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41.
NP Pereira TM Monteiro AC Freitas EJ Barreiro AL Miranda 《Canadian Metallurgical Quarterly》1998,137(3):82-86
A new series 5-thio aryl pyrazole derivatives were proposed aiming analgesic activity. In this work, 8 new compounds of this class were synthesized using usual synthetic methodology, having as key intermediate the 3-methyl-4-nitro-5-chloropyrazole-1-phenyl derivative and subsequent reaction with several nucleophiles sulfides. Pharmacological evaluation of this series showed analgesic activity in the some extent in especially for 5-(4-bromophenyl)-thio-3-methyl-4-nitro-1-phenylpyrazole which was the most potent in this series, presenting an analgesic action comparable to that show by dipyrone. 相似文献
42.
M Miampamba EJ Parr DM McCafferty JL Wallace KA Sharkey 《Canadian Metallurgical Quarterly》1998,12(3):219-228
BACKGROUND: We investigated the effects of benzalkonium chloride (BAC) on trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats. METHODS: TNBS was administered intrarectally before and/or after BAC treatment. In the first study, the effects of treatment with BAC 6, 12 or 24 h after TNBS were examined. In the second study, animals were treated with BAC before, after or before and after TNBS, and were examined 7 days later. The severity of colitis was assessed by macroscopic and histological scoring of the colonic damage and by determination of colonic myeloperoxidase (MPO) activity. Macrophages and CD4+ and CD8+ T cells were examined by immunohistochemistry. RESULTS: When BAC was instilled into the colon 6, 12 or 24 h after TNBS, weight loss and macroscopic and histological features of the colon were similar to that of controls (TNBS alone). In contrast, MPO activity was significantly reduced in all three groups post-treated with BAC. In the groups examined 7 days after TNBS treatment, rats post-treated with BAC exhibited increased weight gain and significantly reduced macroscopic damage and MPO activity compared to the TNBS control group. Rats pre-treated with BAC exhibited less macroscopic damage of the colon than rats receiving only TNBS, but histological damage, MPO and weight gain were unchanged from TNBS controls. Immunohistochemistry revealed that BAC pre-treatment increased the numbers of macrophages and T cells in the colon. After TNBS treatment, macrophage accumulation was evident in the colon, but T cells were scarce. However, these cells were preserved or enhanced in the colonic mucosa in TNBS-treated rats that had been pre-treated with BAC. CONCLUSIONS: Treatment with BAC, particularly after induction of colitis, produces a significant reduction in the severity of tissue injury and inflammation through mechanisms that are not fully understood. 相似文献
43.
Primary focal segmental glomerulosclerosis (FSGS) is a lesion associated with a poor prognosis and results in end-stage renal disease after 5 to 10 years. Based on past experience, many nephrologists have considered primary FSGS a lesion that is steroid resistant and therefore are reluctant to offer steroids as treatment. Recent data, however, have demonstrated that patients with primary FSGS have a response to steroid therapy that is considerably better than had been described. Thus, it may be that nephrologists have been more "steroid reluctant" than the lesion is steroid resistant. To better understand this issue we review the clinical course and response to therapy in patients with primary FSGS. 相似文献
44.
GM Weinstock JM Hardham MP McLeod EJ Sodergren SJ Norris 《Canadian Metallurgical Quarterly》1998,22(4):323-332
Covert brain activity related to task-free, spontaneous (i.e. unrequested), emotional evaluation of human face images was analysed in 27-channel averaged event-related potential (ERP) map series recorded from 18 healthy subjects while observing random sequences of face images without further instructions. After recording, subjects self-rated each face image on a scale from "liked" to "disliked". These ratings were used to dichotomize the face images into the affective evaluation categories of "liked" and "disliked" for each subject and the subjects into the affective attitudes of "philanthropists" and "misanthropists" (depending on their mean rating across images). Event-related map series were averaged for "liked" and "disliked" face images and for "philanthropists" and "misanthropists". The spatial configuration (landscape) of the electric field maps was assessed numerically by the electric gravity center, a conservative estimate of the mean location of all intracerebral, active, electric sources. Differences in electric gravity center location indicate activity of different neuronal populations. The electric gravity center locations of all event-related maps were averaged over the entire stimulus-on time (450 ms). The mean electric gravity center for disliked faces was located (significant across subjects) more to the right and somewhat more posterior than for liked faces. Similar differences were found between the mean electric gravity centers of misanthropists (more right and posterior) and philanthropists. Our neurophysiological findings are in line with neuropsychological findings, revealing visual emotional processing to depend on affective evaluation category and affective attitude, and extending the conclusions to a paradigm without directed task. 相似文献
45.
Pancreatic cancer is a dismal disease. The 5-year overall survival ranges from 1% to 5%. Surgery is the only curative treatment available for this cancer, but it is indicated only in selected patients with a less than 4 cm tumor. In these patients, survival rate is about 30%. We have considered several aspects: the very difficult early diagnosis, the correct diagnostic flow chart, actual surgical procedures and new trends in biologic and genetic research. It is likely that better results can be achieved by defining an "early pancreatic cancer" and establishing how to detect it. This could be the wrigth one way is to significantly improve the survival of these patients. 相似文献
46.
T Ikeda Y Murata EJ Quilligan JT Parer IM Theunissen P Cifuentes S Doi SD Park 《Canadian Metallurgical Quarterly》1998,179(5):1329-1337
OBJECTIVE: We previously showed that in asphyxiated fetal lambs the duration of hypotension correlated well with the severity of histologic damage to the brain, whereas the duration of bradycardia did not. This study compares fetal heart rate patterns with the degree of histologic damage to the brain. STUDY DESIGN: Twelve chronically instrumented near-term fetal lambs were subjected to asphyxia by umbilical cord occlusion until fetal arterial pH was <6. 9 and base excess was <-20 mEq/L. An additional 4 fetuses served as sham-asphyxia controls. Fetal heart rate (from electrocardiogram), arterial blood pressure, fetal breathing movements, and electrocorticogram were continuously monitored before, during, and for 72 hours after asphyxia. Fetal brain histologic features were categorized as mild (group 1, n = 5), moderate (group 2, n = 4), and severe (group 3, n = 3). Long-term fetal heart rate variability expressed as amplitude range was assessed visually every 5 minutes from 30 minutes before asphyxia until 2 hours of recovery and at 6, 12, 24, 48, and 72 hours of recovery. RESULTS: Long-term fetal heart rate variability amplitude decreased from 32 +/- 17 beats/min (mean +/- SEM) preocclusion to 4 +/- 13 beats/min at the end of occlusion (P <.001) without significant differences among the 3 groups. During 10 to 45 minutes of recovery, the long-term variability of group 1 was significantly greater than that of groups 2 and 3. At 24 to 72 hours of recovery, the long-term variability of groups 1 and 2 was significantly higher than that of group 3, which was almost 0. The "checkmark" and sinusoidal fetal heart rate patterns were observed during the recovery period in groups 2 and 3. CONCLUSIONS: Decreased long-term fetal heart rate variability and the "checkmark" and sinusoidal fetal heart rate patterns were indicators of the severity of asphyxial histologic damage in the fetal brain. 相似文献
47.
M Delgado EJ Munoz-Elias Y Kan I Gozes M Fridkin DE Brenneman RP Gomariz D Ganea 《Canadian Metallurgical Quarterly》1998,273(47):31427-31436
48.
BK Yoder WG Richards C Sommardahl WE Sweeney EJ Michaud JE Wilkinson ED Avner RP Woychik 《Canadian Metallurgical Quarterly》1996,50(4):1240-1248
Autosomal recessive polycystic kidney disease (ARPKD) is characterized by the formation of large collecting tubule and ductular cysts that often result in renal insufficiency within the first decade of life. Understanding the process leading to cyst formation will require the identification and characterization of genes involved in the etiology of this disease. In this regard, we previously described the generation of a mouse model (TgN737Rpw) for ARPKD and the cloning of a candidate gene. Here we show direct involvement of the Tg737 gene in collecting duct cyst formation by expressing the wild-type Tg737 cDNA as a transgene in TgN737Rpw mutants. In contrast to TgN737Rpw mutants, the "rescued" animals survive longer, have normal renal function and normal localization of the EGFr to the basolateral surfaces of collecting duct epithelium. 相似文献
49.
P Gennis L Miller EJ Gallagher J Giglio W Carter N Nathanson 《Canadian Metallurgical Quarterly》1996,3(6):568-573
Thirty-five male patients, aged 34-79 yr, with definite rheumatoid arthritis (RA) were recruited from out-patient clinics and randomized to receive monthly injections of testosterone enanthate 250 mg or placebo as an adjunct therapy for 9 months. Endpoints included disease activity parameters and bone mineral density (BMD). At baseline, there were negative correlations between the ESR and serum testosterone (r = -0.42, P < 0.01) and BMD (hip, r = -0.65, P < 0.01). A total of 29.6% of all patients had at least one vertebral fracture, most having multiple fractures. Back pain, however, was not more prevalent in fracture patients (55% vs 50%). Disease activity was significantly higher in the fracture group (joint score P < 0.05, rheumatoid factor P < 0.01). Thirty patients completed the trial, 15 receiving testosterone and 15 receiving placebo. There were significant rises in serum testosterone, dihydrotestosterone and oestradiol in the treatment group. There was no significant effect of treatment on disease activity overall, five patients receiving testosterone underwent a "flare'. Differences in mean BMD following testosterone or placebo were non-significant (spine: +1.2% vs -1.1%; femur: -0.3% vs +0.3%). There was no suggestion of a positive effect of testosterone on disease activity in men with RA. 相似文献
50.
PURPOSE: The effect of systematic and stochastic setup error on the dose delivered to the gap region for the three field radiation treatment of medulloblastoma is studied. The consequences of such setup error is discussed. METHODS AND MATERIALS: The treatment of medulloblastoma is typically a 3 field technique, in which two lateral cranial fields are matched with a spine field. The x-ray dose delivered to the region between the matched fields depends upon the gap size. The choice of the gap width between the cranial and spinal fields is controversial. It is currently a compromise between minimizing the risk of dose hot spots to the spine, and the associated clinical complications, as well as the magnitude of cold spots (underdosing) across the gap, with the associated risk of disease recurrence. In this paper, we examine the effect of gap width with a moving junction, referred to as "field feathering", on the dose across the field junction for a 6MV photon beam. In addition, we have studied 129 portal films and 40 simulation films to assess the accuracy and precision of patient setup during treatment with a plan involving feathered fields. Selected landmarks observable on both portal and simulation films were identified and the variation in the distances to the field edges measured. The distribution of patient setup error was convoluted with the beam profiles for a 6MV linac. These convoluted field edges were used obtain dose profiles across the gap region as a function of gap separation. The consequences for therapy are discussed. In addition, analysis of patient setup error on an alternative treatment involving beam modifiers to broaden the beam penumbra is discussed. RESULTS: The magnitude of the spatial stochastic and systematic setup error was determined to be approximately three and two millimeters respectively. The dosimetric consequences of patient setup error lead to over and under dosing in the spinal gap region for the three field technique. The degree of under or over dose depends on the nature and magnitude of the patient setup error. CONCLUSIONS: The effect of patient setup error can lead to significant dosimetric errors in the dose to the gap region depending on the magnitude of the setup errors. The effective over and under dose can be compensated by the use beams modifiers such as a beam spoiler or vibrating jaws. 相似文献