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排序方式: 共有6497条查询结果,搜索用时 15 毫秒
981.
T Langin JL Pépin S Pendlebury H Baranton-Cantin G Ferretti E Reyt P Lévy 《Canadian Metallurgical Quarterly》1998,113(6):1595-1603
OBJECTIVES: We used upper airway (UA) imaging in 20 patients to determine (1) whether an effective enlargement of the UA is obtained after uvulopalatopharyngoplasty (UPPP), and (2) whether UA modifications explain the results of such surgery. METHODS: Cephalometric measurements were made to assess the posterior airway space, the length and width of the soft palate, and the distance between the hyoid bone and the mandibular plane. Pharyngeal CT measured the airway cross-sectional area (CSA) at each 10-mm slice from 10 mm above (-10) to 40 mm below (+40) the hard palate. Polysomnography was performed before and after surgery (10+/-10 [SD] months). Good responders were defined by an apnea-hypopnea index (AHI) of <10 postsurgery or, in patients in whom AHI was initially <10, a reduction of AHI >50% of the initial AHI. RESULTS: Twenty patients (age=45+/-11 years) were studied. For the whole group, the mean body mass index (26+/-4 kg/m2) and AHI (14+/-13 vs 18+/-16/h) were unchanged after UPPP. The results of the surgery were mediocre with 7 good responders (35%) and 13 nonresponders (65%) defined by polysomnographic criteria. The only changes on UA imaging for the group as a whole after UPPP were decrease in length (40+/-6 vs 29+/-5 mm, p< or =0.0006) and increase in width of the soft palate (11.5+/-2.7 vs 13.6+/-3.5 mm, p< or =0.006). The increase or decrease in minimal CSA at the oropharyngeal (OP) level after UPPP was significantly correlated with the change in AHI (r=-0.54, p<0.02). Moreover, the changes in CSA obtained at the OP level were significant only in the patients who responded favorably to UPPP (7 vs 13 nonresponders). CONCLUSIONS: Postoperative OP enlargement is associated with a good outcome of UPPP. Persistent narrowing in nonresponders could be due to the increase in soft palate width after surgery. 相似文献
982.
G Bompart I Tack E Marin Casta?o JB Pesquero JP Girolami JL Bascands 《Canadian Metallurgical Quarterly》1996,32(1-3):99-101
The effect of subcutaneous injection of cyclosporine (20 mg/kg/day for 3 days) on the expression of kallikrein (Kal) and bradykinin 2 receptor (BK2) mRNA in the rat renal cortex was examined. CsA decreased significantly Kal and BK2 mRNA expression in the kidney cortex. These results indicate that the kallikrein-kinin system may participate in the genesis or the aggravation of the renal haemodynamic effect induced by long term administration of CsA. 相似文献
983.
984.
985.
Cytogenetic abnormalities in human malignancies frequently involve chromosome 7. The existence of several tumor suppressor genes on the long arm of chromosome 7 has been suggested in both epithelial and hematologic malignancies. From the Danish Cytogenetic Register, we identified 183 persons with constitutional abnormalities involving chromosome 7, including 16 patients with Williams syndrome. By linkage to the Danish Cancer Registry, we found five persons with cancer, including one thyroid carcinoma, three carcinomas of the digestive tract, and one malignant melanoma. There were no cases of leukemia. The overall risk of developing cancer was not increased. 相似文献
986.
Characterization of the embryotrophic activity of exogenous protein-free oviduct-conditioned medium used in culture of cattle embryos 总被引:1,自引:0,他引:1
P Mermillod A Vansteenbrugge C Wils JL Mourmeaux A Massip F Dessy 《Canadian Metallurgical Quarterly》1993,49(3):582-587
Bovine zygotes, obtained after in vitro maturation and fertilization of oocytes from slaughtered cow ovaries, were cultured in droplets of nonconditioned or conditioned medium on bovine oviduct cell monolayers. The media tested were Medium 199 alone and Medium 199 supplemented with 10% fetal calf serum (FCS). Oviduct conditioning increased both early cleavage and development to blastocysts. Only the effect on early cleavage was mimicked by FCS. The blastocysts obtained in serum-free conditioned medium (SFCM) appeared morphologically normal and had the same cell number as those produced in conditioned medium containing serum. Their hatching rates did not differ. Transfer of 16 blastocysts developed in SFCM to 16 synchronized recipients resulted in five pregnancies (31%), indicating good embryonal viability. Boiling of SFCM resulted in a total loss of activity, while heating at 56 degrees C for 30 min had no deleterious effect. A 10-kDa ultrafiltration of SFCM removed the blastocyst development-supporting activity from the filtrate but not the early cleavage-favoring activity. This allows us to conclude that at least two different factors are present in SFCM: one of low molecular mass (< approximately 10 kDa), needed to obtain the 5-8 cell stage and mimicked by FCS, and another of higher molecular mass allowing embryos to develop from the 8-cell to blastocyst stage. 相似文献
987.
Two young patients (20 and 21 years) had recurrent hyperparathyroidism following neck exploration. Non-invasive investigations failed to localize a parathyroid adenoma. In both cases selective catheterization of the internal mammary arteries combined with digital angiography demonstrated hypervascular mediastinal adenomas. Using a coaxial catheterization technique (Tracker 18 and 10), both branch arteries of the internal mammary supplying the adenoma were selectively catheterized. In one case absolute alcohol and the other a mixture of Lipiodol and absolute alcohol were used to effect the ablation. The procedures were uneventful and serum calcium levels have subsequently returned to within normal limits. The follow-up in these two cases extends to 2 1/2 years in one and 10 months in the other case. 相似文献
988.
HG Munshi DJ Burks JL Joyal MF White DB Sacks 《Canadian Metallurgical Quarterly》1996,35(49):15883-15889
IRS-proteins couple the receptors for insulin and various cytokines to signalling proteins containing Src homology 2 (SH2) domains. Here we demonstrate that calmodulin, a mediator of Ca(2+)-dependent physiological processes, associates with IRS-1 in a phosphotyrosine-independent manner. IRS-1 coimmunoprecipitated with calmodulin from lysates of Chinese hamster ovary cells expressing IRS-1. The interaction was modulated by Ca2+, and calmodulin binding to IRS-1 was enhanced by increasing intracellular Ca2+ with A23187. In contrast, trifluoperazine, a cell-permeable calmodulin antagonist, decreased binding of calmodulin to IRS-1. Insulin stimulated tyrosine phosphorylation of IRS-1, but did not significantly alter the interaction between calmodulin and IRS-1. IQ-like motifs occur between residues 106-126 and 839-859 of IRS-1. Synthetic peptides based on the these sequences inhibited the association between IRS-1 and calmodulin. These data demonstrate that calmodulin binds to IRS-1 in intact cells in a Ca(2+)-regulated manner, providing a molecular link between the signalling pathways. 相似文献
989.
A feature common to all congenital or inflammatory abnormalities of the cervical spine is an actual or potential reduction in the lumen of the spinal canal. The spinal cord and nerve roots are at risk. During intubation, and positioning the patient on the table, all untoward movements of the cervical spine may lead to spinal cord compression. Abnormalities of the cervical spine carry the risk of a difficult intubation. If there is much debate as to what constitutes optimum management of the airway, there is no evidence that any one method is the best. Recognizing the possible instability and intubating with care, are probably much more important in preserving neurological function than any particular mode of intubation. During maintenance of anaesthesia, the main goal is to preserve adequate spinal cord perfusion in order to prevent further damage. Spinal cord blood flow seems to be regulated by the same factors as cerebral blood flow. Hypercapnia increases cord blood flow while hypocapnia decreases it. Therefore, normocapnia or mild hypocapnia is recommended. Induced hypotension is frequently used to decrease blood loss. However, in patients with a marginally perfused spinal cord, the reduction in blood flow may cause ischaemia of the spinal cord and may therefore be relatively contraindicated. In addition to standard intraoperative monitoring, spinal cord monitoring is almost mandatory. Monitoring somatosensory evoked potentials is used routinely. However, the major limitation is that this technique only monitors dorsal column function; theoretically, motor paralysis can occur despite a lack of change in recorded signals. Neurogenic motor evoked potentials may now be used to monitor anterior spinal cord integrity.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
990.
Y Le Scao J Jezequel A Robier JL Baulieu A Turzo B Guias PP Morin 《Canadian Metallurgical Quarterly》1993,20(5):387-390
Development of auditory stimulation tests associated with single-photon emission tomography (SPET) shows evidence of variations in perfusion related to the stimuli. Three brain SPET examinations with technetium-99m hexamethylpropylene amine oxime were performed on eight right-handed adults with normal hearing, the first one without stimulation and the other two associated with a 500-Hz/30-dB stimulation of the right ear. Temporal regions of interest covering auditory areas, as well as parietal ones (internal control), were drawn on three successive coronal slices. A cortico-cerebellar index R was calculated, and the variation in activity was defined for each subject using the ratio R poststimulation--R prestimulation/R prestimulation. A significant increase in the temporal cortex count occurred in all subjects. This increase was bilateral, except for one subject in whom it was not significant on the right side. This result recurred during the second stimulation study. Overall the response of the left temporal cortex was stronger, although the asymmetry was not significant. The asymmetry repeated itself after each stimulation. The perfusion response is globally reliable in our study. We must ascertain how sensitive this test is with regard to deaf adults and adults with normal hearing before extending its use to children. 相似文献