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31.
N Abdeen L Souhami C Freeman M Yassa T Roman 《American journal of clinical oncology》1992,15(1):87-90
A retrospective review of 69 patients with testicular seminoma, stage I and II, treated by orchiectomy and adjuvant irradiation at McGill University Hospitals from 1972 to 1987 was performed. All patients underwent either lymphangiogram or computed axial tomography scan for evaluation of retroperitoneal disease. There were 52 stage I (75%), 13 stage IIA (11%), 2 stage IIB (3%), and 2 stage IIC (Royal Marsden Hospital staging criteria). Median follow-up time was 6.2 years. The 10-year actuarial survivals were 94% and 93% for stages I and II, respectively. Only two stage I patients failed treatment, and both died from metastatic disease. Interestingly, both developed biopsy-proven metastatic brain disease and had no evidence of intra-abdominal recurrence. In stage II disease, only one patient failed the treatment. There was no serious acute toxicity and no late complications have been encountered. Radiation therapy following orchiectomy is the treatment of choice for stage I and for most stage II patients with testicular seminoma. The controversial aspects of radiographic retroperitoneal staging, the use of prophylactic mediastinal irradiation for stage II patients, and the role of surveillance only for stage I patients are discussed. 相似文献
32.
Delayed-type hypersensitivity elicited by synthetic peptides complexed with Mycobacterium tuberculosis hsp 70. 总被引:1,自引:0,他引:1
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Four synthetic peptides bearing dominant CD4+ T-cell epitopes of the 19,000 and 38,000 MW proteins of Mycobacterium tuberculosis were used to provoke a delayed-type hypersensitivity (DTH) reaction in mice previously immunized with recombinant 19,000 and 38,000 MW proteins. It was found that an effective enhancement of the DTH reaction was obtained if the peptides were administered as a complex with M. tuberculosis hsp 70 protein. The increase in reactivity was not obtained when hsp 70 and peptide were co-injected at the same site, but not in complex, or when the specific peptide was displaced from the complex by an irrelevant peptide with high capacity to bind hsp 70. One of the antigenic peptides whose capacity to complex with hsp 70 is low, failed to show the enhancement of DTH when injected together with hsp 70. 相似文献
33.
Carlos Heitor Cunha Moreira Fabricio Batistin Zanatta Raquel Antoniazzi Priscila Ceolin Meneguetti Cassiano Kuchenbecker R?sing 《Journal of applied oral science : revista FOB》2007,15(5):437-441
When dealing with patients with periodontal disease of variable severities, dentists must often choose between treating and restoring the involved tooth or indicating its extraction. Different criteria have been adopted in this decision-making process. The purpose of this study was to evaluate the criteria adopted by dentists to indicate the extraction of teeth with periodontitis. Dentists were interviewed at their private practices in three cities of the state of Rio Grande do Sul, Brazil. The evaluated criteria included severity of attachment loss, tooth mobility, furcation involvement, prosthetic planning, periodontal-endodontic lesion, possible systemic involvement due to the presence of periodontitis, referral to a periodontist for evaluation, radiographic bone loss greater than 50%, presence of extensive caries, socio-economic and cultural status of the patient, among others. The most often adopted criteria to indicate the extraction of periodontally affected teeth were the presence of mobility (37.5%), severity of attachment loss (24.3%) and radiographic bone loss greater than 50% (21.2%). The results of the present study demonstrated the difficulties faced by dentists to indicate the extraction of teeth with severe attachment loss, in addition to the establishment of an adequate prognosis. Aspects associated with the past disease were still the most often reported to indicate the extraction of teeth for periodontal reasons. 相似文献
34.
Waclaw Weyde Roman Badowski Magdalena Krajewska Jozef Penar Krzysztof Moron Marian Klinger 《Nephrology, dialysis, transplantation》2004,19(6):1618-1621
BACKGROUND/AIMS: Catheterization of the femoral vein is a safe and recommended method of temporary access for haemodialysis. In some patients, however, because of the lack of other possibilities, it is necessary to maintain long-term femoral cannulation. The aim of the study was to evaluate the frequency of stenosis after prolonged femoral cannulation. METHODS: The 24 patients incorporated in the study were divided into two groups. Group 1 consisted of 10 end-stage kidney failure patients (four females and six males, aged 32-75 years, average 55.6+/-13.6 years) in whom femoral catheters were maintained for less than 2 weeks (5-14 days, average 9.3+/-3.6 days). Group 2 included 14 chronic haemodialysis patients (six females and eight males aged 23-65 years, average 49.5+/-13.27 years). The time of catheter maintenance ranged from 2 to 16 weeks (average 6.4+/-4.2 weeks). Femoral and iliac vein status was evaluated using magnetic resonance imaging. RESULTS: A feature of venous stenosis of both the femoral and iliac veins was disclosed in four patients in whom femoral cannulation lasted more than 4 weeks. There were no stenoses in group 1. CONCLUSION: Long-term femoral cannulation for more than 4 weeks may be associated with a significant risk of stenosis in the femoral and/or external iliac veins. 相似文献
35.
Raquel Carreira Ana Duarte Pedro Monteiro Maria Sancha Santos Ana Cristina Rego Catarina R Oliveira Lino M Gon?alves Luís A Providência 《Revista portuguesa de cardiologia》2004,23(11):1447-1455
Ischemia negatively affects mitochondrial function by inducing the mitochondrial permeability transition (MPT). The MPT is triggered by oxidative stress, which occurs in mitochondria during ischemia as a result of diminished antioxidant defenses and increased reactive oxygen species production. It causes mitochondrial dysfunction and can ultimately lead to cell death. Therefore, drugs able to minimize mitochondrial damage induced by ischemia may prove to be clinically effective. We analyzed the effect of carvedilol, a beta-blocker with antioxidant properties, on mitochondrial dysfunction. Carvedilol decreased levels of TBARS (thiobarbituric acid reactive substances), an indicator of oxidative stress, which is consistent with its antioxidant properties. Regarding cell death by apoptosis, although ischemia did increase caspase-8-like activity, there were no changes in caspase-3-like activity, which is activated downstream of caspase-8; this may indicate that the apoptotic cascade is not activated by 60 minutes of ischemia. We conclude that carvedilol protects ischemic mitochondria by preventing oxidative mitochondrial damage, and, by so doing, it may also inhibit the formation of the MPT pore. 相似文献
36.
Michelle McKerral Pierre Lachapelle François Tremblay Robert C. Polomeno Marie-Sylvie Roy Raquel Beneish Franco Leporé 《Documenta ophthalmologica. Advances in ophthalmology》1995,91(2):181-193
The contribution of each monocular pathway to the timing of the binocular pattern visual evoked potential was assessed in situations where a significant interocular timing discrepancy was observed. Monocular and binocular pattern visual evoked potentials to 0.5° checks were recorded from normal subjects, normal subjects in whom one eye was blurred, patients with monocular amblyopia, and patients with resolved unilateral optic neuritis. Normal subjects showed facilitation, while suppression was evidenced in subjects with monocular blurring. In patients with amblyopia, the affected pathway had no effect on binocular pattern visual evoked potential latency, suggesting that the amblyopic eye was suppressed. In contrast, all patients with optic neuritis showed binocular averaging. Our results show that different forms of binocular interaction are evidenced in normal subjects, in amblyopia and in optic neuritis, and suggest that a comparative analysis of monocular and binocular pattern visual evoked potential peak times brings valuable information to the clinical evaluation that could be used to distinguish disease processes further.Abbreviation BPVEP
binocular pattern visual evoked potential 相似文献
37.
Butyrate infusions in the ovine fetus delay the biologic clock for globin gene switching. 总被引:4,自引:0,他引:4
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S P Perrine A Rudolph D V Faller C Roman R A Cohen S J Chen Y W Kan 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(22):8540-8542
The switch from fetal to adult hemoglobin expression is regulated in many mammalian species by a developmental clock-like mechanism and determined by the gestational age of the fetus. Prolonging fetal globin gene expression is of considerable interest for therapeutic potential in diseases caused by abnormal beta-globin genes. Butyric acid, which is found in increased plasma concentrations in infants of diabetic mothers who have delayed globin gene switching, was infused into catheterized fetal lambs in utero during the time of the normal globin gene switch period. The globin gene switch was significantly delayed in three of four butyrate-treated fetuses compared with controls and was entirely prevented in one fetus in whom the infusion was begun before the globin switch was under way. These data provide a model for investigating and arresting the biologic clock of hemoglobin switching. 相似文献
38.
BALB/c mice were bilaterally implanted with bipolar electrodes either in anterodorsal (ADH) or posteroventral hippocampus (PVH) in order to compare the effects of postsession electrical stimulation on memory processes. For each experiment, 30 s after the end of the first session, the animals were stimulated during 80 s. For both hippocampal regions, the stimulation intensity was half of the afterdischarge threshold value. Control groups were naive, ADH and PVH implanted non-stimulated animals. Different appetitive and aversive tasks were used. Subseizure stimulation never created a deficit. Depending on the region of the hippocampus stimulated and on the learning task, a retention enhancement was eventually observed. These data are in agreement with the involvement of hippocampus in initial stages of memory consolidation. Further, the subseizure stimulation permitted a functional dissociation between the two hippocampal regions. Both regions seemed involved in the integration of information, but the anterodorsal part would be rather related to behavioral inhibition, while the posteroventral part would have the capacity to induce an arousal state allowing behavioral flexibility. 相似文献
39.
J S Sawyer R F Baldwin L E Rinkema C R Roman J H Fleisch 《Journal of medicinal chemistry》1992,35(7):1200-1209
This report describes the development of a series of highly potent quinoline-based leukotriene D4 (LTD4) receptor antagonists containing an N-benzyl-substituted phenyltetrazole moiety. They were designed to provide both the correct positioning of the acidic function and secondary lipophilic domain required for strong receptor binding. Members of this series possess high activity in blocking LTD4-induced contractions of isolated guinea pig ileum. Compound 32, LY287192 (2-[[5-[3-[2-(7-chloroquinolin-2- yl)ethenyl]phenyl]-2H-tetrazol-2-yl]methyl]-5-fluorobenzoic acid sodium salt), blocked contraction with a pKB value of 9.1 +/- 0.3. Qualitative structure-activity studies have demonstrated specific requirements for the best activity. In particular, ortho substitution of the benzyl group with an acidic function was crucial for maximum potency. In cases similar to 32, where the benzyl group possesses an ortho carboxylate, the N-2-substituted tetrazole isomer showed 100-fold greater activity relative to the corresponding N-1 isomer. This pattern was reversed when the acid was substituted at the para position. The quinoline unit may be replaced by other nitrogen-containing heterocycles. 相似文献
40.
J E Azevedo M A Fernandez D San Roman E Torrecilla R Esturau J Hernandez T Echeverria A Burgueno J L Delcan 《Revista portuguesa de cardiologia》1992,11(6):531-537
AIM OF STUDY: Evaluation by transesophageal echocardiography of the effect on the characteristics of physiological regurgitant jets (JF) resulting from prosthetic disfunction due to pathologic regurgitation (JF). PATIENTS AND METHODS: We studied 69 consecutive patients with the diagnosis of prosthesis in mitral position using transesophageal echocardiography and color doppler codification. The patients were divided in two groups (N and D groups) according to the presence of prosthesis disfunction by pathologic regurgitation. In each patient we determined planimetric areas and atrial peak depth of each JF and also the sum of JF planimetric areas of each mitral prosthesis. When pathological regurgitation was present we calculated the highest planimetric area, severity degree and atrial peak depth in each JP. RESULTS: The planimetric area in each JF of group N was 330 +/- 167 mm2 and in group D 117 +/- 116 mm2 (p less than 0.001). The sum of the areas of JF in group N was 474 +/- 204 mm2 and in group D 254 +/- 176 mm2 (p less than 0.01). The atrial depth of JF in group was 32 +/- 15 mm and in group D 26 +/- 18 mm (p less than 0.01). In group D 29% of the patients had mild pathological regurgitation, 10% moderate and 61% severe. The maximum planimetric area of JP in group D was 1078 +/- 1007 mm2 with atrial depth of 37 +/- 28 mm. CONCLUSION: The pathological regurgitation in disfunction prosthesis in mitral position has a significant reduction effect in the dimension of prosthesis physiologic regurgitation jets. This transesophageal echocardiographic observation makes it possible to characterize and clarify more precisely the different types of mitral prosthesis jets. 相似文献