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91.
Jaafar Mouhyi Lars Sennerby Jeanjacques Pireaux Nicolas Dourov Samir Nammour Jack Van Reck 《Clinical oral implants research》1998,9(3):185-194
The purpose of the present study was to analyse clinically failed and retrieved implants prior to and after cleaning by means of scanning electron microscopy (SEM) and X-ray induced photoelectron spectroscopy (XPS) as compared to unused controls. Six different chemical and physical techniques for cleaning of contaminated titanium implants were evaluated: 1) rinsing in absolute ethanol for 10 min, 2) cleaning in ultrasonic baths containing trichloroethylene (TRI) and absolute ethanol, 10 min in each solution, 3) abrasive cleaning for 30 s, 4) cleaning in supersaturated citric acid for 30 s, 5) cleaning with continuous CO2-laser in dry conditions at 5 W for 10 s, 6) cleaning with continuous CO2-laser in wet conditions (saline) at 5 W for 10 s. SEM of failed implants showed the presence of contaminants of varying sizes and XPS showed almost no titanium but high carbon signals. XPS of unused titanium implants showed lower levels of titanium as previously reported, probably due to contamination of carbon which increased with time in room air. Cleaning of used implants in citric acid followed by rinsing with deionized water for 5 min followed by cleaning in ultrasonic baths with TRI and absolute ethanol gave the best results with regard to macroscopical appearance and surface composition. However, as compared to the unused implants the results from an element composition point of view were still unsatisfactory. It is concluded that further development and testing of techniques for cleaning of organically contaminated titanium is needed. 相似文献
92.
L.-J. Van Bogaert 《Medical hypotheses》1997,48(6):485-488
With spinal anesthesia the level of surgical analgesia is mostly reported without reference to the neuroanatomic map of spinal nerves. The classical maps are variably and inconsistently reported in many textbooks. Because of the differences between the classical maps of Keegan and Garrett and of Foerster, and also because of the variability in their interpretation, we applied them to the same clinical data. This resulted in a theoretically clinically significant difference of two segments. It is concluded that clear reference should be made to the implemented segmental map in expressing the level of spinal blockade. 相似文献
93.
Arnold Criel Gregor Verhoef Robert Vlietinck Cristina Mecucci Johan Billiet Lucienne Michaux Peter Meeus ries Louwagie Angeline Van Orshoven Achiel Van Hoof Mark Boogaerts Herman Van den Berghe & Chris De Wolf-Peeters 《British journal of haematology》1997,97(2):383-391
We analysed a group of 390 patients, diagnosed with chronic lymphocytic leukaemia (CLL). Cases were subclassified as morphologically typical and atypical CLL according to the criteria of the FAB proposal. Typical CLL cases were mostly diagnosed at a low-risk stage (Binet A/Rai 0), required no immediate treatment and expected a long survival; atypical CLL cases mostly presented at a more advanced risk stage (Binet B/Rai I–II), usually required immediate treatment and their survival was shorter. Moreover, clinical staging was of prognostic significance in typical but not in atypical cases. In typical CLL, del(11q) was the most common chromosomal abnormality (21%) whereas in atypical CLL trisomy 12 was found in about 65% of the cases documented with an abnormal karyotype. Although chromosomal abnormalities were associated with a poor survival in typical CLL, they are of no prognostic significance in atypical CLL. Based on these data, we conclude that subtyping CLL by morphology enables the identification of two groups of cases, each characterized by a specific clinical presentation, different cytogenetic abnormalities and prognostic parameters. We speculate that these two groups may represent two related, but different, diseases with different prognostic parameters and a different survival. 相似文献
94.
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97.
Walter F. McKeever Karen S. Seitz Annette J. Krutsch Patti L. Van Eys 《Neuropsychologia》1995,33(12):1627-1635
Rasmussen and Milner [N.Y. Acad. Sci. Vol. 299, pp. 355–379, 1977] published data on late-lesioned (after age 6) epileptic patients who had suffered left hemisphere lesions. They estimated that left hemisphere dominance occurred in 96% of dextrals and 70% of sinistrals. These figures have been regarded as valid estimates for normal dextrals and sinistrals. We administered the Bilateral Object Naming Latency Task, a verbal tachistoscopic task with very good psychometric properties, to 188 dextral and 72 sinistral normals. Results showed that 93.6% of the dextrals and 80.3% of the sinistrals were left hemisphere dominant. A consideration of results from a number of carefully conducted dichotic listening studies suggests, as do present results, that the 70% left-dominance estimate of Rasmussen and Milner for normal sinistrals may be too low by about 10%. It is suggested that ‘bilateral dominance’, present in 15% of the epileptic sinistrals of Rasmussen and Milner, may be much less common in normal sinistrals. 相似文献
98.
Mitogenic effects of thyrotropin and adenosine 3',5'-monophosphate in differentiated normal human thyroid cells in vitro 总被引:2,自引:0,他引:2
P Roger M Taton J Van Sande J E Dumont 《The Journal of clinical endocrinology and metabolism》1988,66(6):1158-1165
Previous studies of human thyroid cells in culture (mostly from pathological tissues) failed to demonstrate a mitogenic effect of TSH, leading to the proposal that the growth effect of TSH in vivo might be indirect. To reexamine the influence of TSH on DNA synthesis and cell proliferation, we established primary cultures of normal thyroid tissue from nine subjects. When seeded in a 1% serum-supplemented medium, thyroid follicles released by collagenase/dispase digestion developed as a cell monolayer that responded to TSH by rounding up and by cytoplasmic retraction. When seeded in serum-free medium, the cells remained associated in dense aggregates surrounded by few slowly spreading cells. In the latter condition, the cells responded to TSH and other stimulators of cAMP production, such as cholera toxin and forskolin, by displaying very high iodide-trapping levels. Exposure to serum irreversibly abolished this differentiated function. TSH stimulated the proliferation (as shown by DNA content per culture dish) of 1% serum cultured cells (doubling times were reduced from 106 to 76 h) and increased by 100% the [3H]thymidine labeling indices. In serum-free cultured cells (dense aggregates or cell monolayers after initial seeding with serum), control levels of DNA synthesis were lower, and up to 8-fold stimulation of DNA synthesis occurred in response to 100 mU/L TSH (stimulation was consistently detected with 20 mU/L), based on measurements of [3H]thymidine incorporation into acid-precipitable material and counts of labeled nuclei on autoradiographs (up to 40% labeled nuclei within 24 h). The mitogenic effect of TSH required a high insulin concentration (8.3 X 10(-7) mol/L) or a low insulin-like growth factor I concentration. The mitogenic effects of TSH were mimicked in part by cholera toxin, forskolin, and dibutyryl cAMP. Epidermal growth factor and phorbol myristate ester also stimulated thyroid cell proliferation and DNA synthesis, but they potently inhibited TSH-stimulated iodide transport. We conclude that TSH, acting at least in part through cAMP, is a potent growth factor for human thyroid cells and thus provide an experimental basis in vitro for the well established in vivo goitrogenic action of TSH. 相似文献
99.
P. E. R. Rhemrev W. A. A. Van Os D. A. Edelman H. H. Badrawi 《Advances in Contraception》1988,4(2):125-130
In a follow-up evaluation of 3721 Multiload IUD users, the removal rate for medical reasons other than bleeding/pain was only 2.6 per 100 women at three years. Most of these removals were for reasons that appeared to be unrelated to IUD use. The removal rate for pelvic inflammatory disease was 0.3 per 100 woman years. Women were followed up for up to three years after removal of their IUDs. Among women with PID at least 70% of those who desired pregnancy subsequently became pregnant, a rate similar to that of women who had their IUDs electively removed to become pregnant. The study provides further data on the safety of intrauterine contraception.
Resumen Durante el seguimiento de 3721 usuarias del DIU Multiload, la tasa de remociones por otras razones médicas que sangrado/dolor, fué de 2.6 por 100 mujeres en tres años. La mayoría de estas remociones fueron hechas por razones que parecen no estar relacionadas con el uso del DIU. La tasa de remociones por enfermedad inflamatoria pelviana fué de 0.3 por 100 años-mujer. Las mujeres tuvieron seguimiento hasta tres años después de la remoción de sus DIU. Entre las mujeres con enfermedad inflamatoria pelviana, al menos 70% de las que desearon un embarazo lo consiguieron; una tasa similar a la de mujeres que eligieron la remoción del DIU para quedar embarazadas. El estudio proporciona más información sobre la inocuidad de la anticoncepción intrauterina.
Résumé Lors d'une évaluation de suivi effectuée sur 3721 utilisatrices de DIU Multiload, le taux de retrait pour des raisons médicales autres que des pertes sanguines/douleurs n'a atteint que 2,6 pour cent des femmes après trois ans. La plupart de ces retraits ont été pratiqués pour des raisons qui ne semblaient pas liées à l'utilisation du DIU. Le taux de retrait pour cause d'inflammation pelvienne s'est élevé à 0,3 pour cent femmes-an. Les femmes ont été suivies pendant des périodes allant jusqu'à trois ans après le retrait du DIU. Parmi les patientes qui avaient contracté une inflammation pelvienne, 70% au moins de celles qui souhaitaient une grossesse sont par la suite devenues enceintes; taux semblable à celui des femmes qui avaient choisi de ne plus porter leur DIU précisément pour avoir un enfant. Cette étude fournit des données supplémentaires sur la sécurité qu'apporte la contraception intrautérine.相似文献
100.
Regulation of Neutrophil Apoptosis by Tumor Necrosis Factor-alpha : Requirement for TNFR55 and TNFR75 for Induction of Apoptosis In Vitro 总被引:7,自引:2,他引:5