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991.
992.
Garcia S Gimferrer JM Iglesias M Catalan M Martinez E Macchiarini P 《The Annals of thoracic surgery》2006,82(4):1545-1546
Adapting a silicone tracheal safe T-tube is a simple method to guarantee upper airway permeability. Its making and availability ease offers a cheap and valid option to avoid the complications of the tracheostomy tube. 相似文献
993.
994.
Palomares T Castro B del Olmo M Iglesias A Bilbao P Alonso-Varona A 《Anti-cancer drugs》2006,17(10):1127-1139
Differentiation therapy with retinoic acid has been considered a potential approach for treating rhabdomyosarcoma. Analysis of retinoids as differentiating agents for rhabdomyosarcoma is, however, rendered incomplete by the fact that some rhabdomyosarcoma cell lines are retinoic acid resistant. Therefore, the aim of the present work was to study the effect of all-trans-retinoic acid on two rat tumour cell lines, derived from the same rhabdomyosarcoma tumour model (i.e. the moderately differentiated low metastatic F21 cell line and the poorly differentiated high metastatic S4MH cell line), to discover how degree of differentiation and glutathione metabolism influence response to this retinoic acid derivative. We observed that whereas in the S4MH cell line all-trans-retinoic acid induced a significant inhibition of tumorigenic potential, in F21 cells all-trans-retinoic acid enhanced tumour growth and only at a higher dose was there a slight antiproliferative effect. These effects were in consonance with the activity level of gamma-glutamyltranspeptidase, which was significantly increased in F21 cells, but not in S4MH cells, in response to the all-trans-retinoic acid-induced increase in reactive oxygen species. The pro-tumour effect observed in F21 cells was reversed by adding buthionine sulphoximide, a specific cellular glutathione-depleting agent, to the all-trans-retinoic acid treatment. This combination produced a decrease in gamma-glutamyltranspeptidase activity, and an increase in oxidative stress and apoptosis. Our findings suggest that the response to all-trans-retinoic-acid of the tumour cell lines studied is influenced by the strong relationship between intracellular glutathione content, gamma-glutamyltranspeptidase activity and degree of differentiation of the rhabdomyosarcoma cell line, and that this relationship should be taken into account when identifying 'retinoid-sensitive' tumours. 相似文献
995.
996.
997.
Assessment of the proliferative,apoptotic and cellular renovation indices of the human mammary epithelium during the follicular and luteal phases of the menstrual cycle 总被引:1,自引:0,他引:1
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Navarrete MA Maier CM Falzoni R Quadros LG Lima GR Baracat EC Nazário AC 《Breast cancer research : BCR》2005,7(3):R306-R313
Introduction
During the menstrual cycle, the mammary gland goes through sequential waves of proliferation and apoptosis. In mammary epithelial cells, hormonal and non-hormonal factors regulate apoptosis. To determine the cyclical effects of gonadal steroids on breast homeostasis, we evaluated the apoptotic index (AI) determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining in human mammary epithelial cells during the spontaneous menstrual cycle and correlated it with cellular proliferation as determined by the expression of Ki-67 during the same period. 相似文献998.
Pregnancy with concomitant chorangioma and placental vascular malformation with mesenchymal hyperplasia 总被引:2,自引:1,他引:2
Chen CP; Chern SR; Wang TY; Huang ZD; Huang MC; Chuang CY 《Human reproduction (Oxford, England)》1997,12(11):2553-2556
We present two pregnancies associated with normal live births and the
unusual concomitance of chorangioma and placental vascular malformation
with mesenchymal hyperplasia. The enlarged placenta had the characteristic
findings of chorangioma, dilated and varicose chorionic vessels and
multiple vesicle-like villi containing hyaluronic acid. The vesicle-like
villi showed diploid cellular DNA contents. Molecular genetic analysis
using the polymerase chain reaction amplification of polymorphic
microsatellite markers confirmed genetic identity among the chorangioma,
the vesicle-like villi and the fetus. Both pregnancies were complicated by
polyhydramnios, pre-term labour and prematurity. One neonate suffered from
anaemia and thrombocytopenia. Another neonate suffered from
haemangiomatosis. Our cases demonstrate that concomitant chorangioma and
placental mesenchymal hyperplasia are genetically identical to the fetus
and can coexist with a normal viable fetus. Since haemangiomas,
chorangiomas, chorionic vessels and villi mesenchymal cells are all derived
from the mesoderm, a combination of fetal haemangiomas, placental vascular
malformation, chorangiomas and placental mesenchymal hyperplasia may
represent a mixed form of congenital malformation of the mesoderm.
相似文献
999.
Medroxyprogesterone acetate with Zoladex for long-term treatment of fibroids: effects on bone density and patient acceptability 总被引:1,自引:0,他引:1
Caird LE; West CP; Lumsden MA; Hannan WJ; Gow SM 《Human reproduction (Oxford, England)》1997,12(3):436-440
A randomized trial was carried out to investigate the effect of 12 months
administration of the gonadotrophin-releasing hormone agonist (GnRHa)
Zoladex in combination with either placebo or medroxyprogesterone acetate
(MPA) from the third month. Bone density, markers of bone resorption,
symptoms and uterine volume were monitored in 24 women with symptomatic
fibroids or menstrual problems. A total of 21 women were recruited to act
as controls for the assessment of bone parameters. Vasomotor side-effects
were reduced significantly in the MPA-treated group. The reduction in
uterine volume in women with fibroids was not impaired by the addition of
MPA. The bone markers osteocalcin and alkaline phosphatase were assessed in
plasma, and the cross-links pyridinoline and deoxypyridinoline measured in
urine. Changes in these markers are reported which suggest increases in
bone resorption during the period of observation. Bone mineral density
(BMD) was assessed by dual energy X-ray absorptiometry at the spine and
forearm. The net reduction in BMD at the spine in the treated groups was
4.30 +/- 0.59% at 6 months and 7.50 +/- 0.78% at 1 year, with no change in
the control group. No change was seen in forearm BMD. No protective effect
was observed when MPA was added. At 1 year after the completion of
treatment, BMD remained significantly below baseline, and this has
implications for the prolonged use of GnRHa.
相似文献
1000.
Task-related changes in propriospinal excitation from hand muscles to human flexor carpi radialis motoneurones 总被引:1,自引:1,他引:1
Caroline Iglesias Véronique Marchand-Pauvert George Lourenço David Burke Emmanuel Pierrot-Deseilligny 《The Journal of physiology》2007,582(3):1361-1379
This study addresses whether there is excitation from human hand muscles to flexor carpi radialis (FCR) motoneurones mediated through propriospinal circuits and, if so, whether it is used in specific motor tasks. Electrical stimuli to the ulnar nerve at wrist level produced an excitation in FCR motoneurones with characteristics typical of a propriospinally mediated effect: low threshold (0.6 × motor threshold (MT)), a group I effect that was not reproduced by purely cutaneous stimuli, long central delay (4.1 ± 0.4 ms in single units), suppression when the stimulus intensity was increased, and facilitation of the corticospinal excitation at the premotoneuronal level. Ulnar-induced propriospinally mediated excitation was compared during selective voluntary contractions of the FCR and, at equivalent level of FCR EMG, during tasks in which the FCR was activated automatically in postural contractions rather than voluntarily (grip, pinching and pointing). The excitation was significantly greater during grip (and pinching) than during voluntary FCR contractions and pointing, whether measured in single motor units or tonic EMG activity, or whether the response to motor cortex stimulation was assessed as the compound motor-evoked potential or the corticospinal peak in single units. The discrepancy between the tasks appeared with ulnar intensities above 0.8 × MT and was then present across a wide range of stimulus intensities. This suggests a reduction in the corticospinal control of 'feedback inhibitory interneurones' mediating peripheral inhibition to propriospinal neurones during grip and pinching. The resulting more effective background excitation of propriospinal neurones by the peripheral input from hand muscles could contribute to stabilizing the wrist during grip. 相似文献