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L Giorgi A Di Filippo A Franchini L Rizzo S Benvenuti M Conti GP Novelli 《Canadian Metallurgical Quarterly》1994,60(1-2):43-47
OBJECTIVE: The reflex response to orotracheal intubation provokes an increase of arterial pressure accompanied by an increase of chorioides volume and a consequent ocular hypertone. There are several methods to reduce the reflex response due to intubation. One of the most effective is topical anaesthesia of larynx and trachea. Experiments were directed to evaluate the efficacy of topical anaesthesia to reduce the intraocular hypertone due to orotracheal intubation. DESIGN: A prospective randomized mask study was conduct on patients undergoing ophthalmologic (anterior segment) surgery at the Eye Clinic of Florence University. METHODS: Intraocular pressure was measured by a Goldman tonometer at four times: T0 = basal, T1 = 2' minutes after induction of general anaesthesia, T2 = 2' minutes after laryngoscopy, T3 = 2' minutes after orotracheal intubation. At the same moments, systolic blood pressure, heart rate, rate pressure pro duct were measured. Patients were randomly divided in two groups: Group L (n = 10) in which was evaluated the efficacy of laryngotracheal topical spray of lidocaine 4% (2 ml) and Group F (n = 10) in which saline was used instead of anesthetic. The filling of the LTA kit (Abbott) was made by a person not involved in the experiments. DATA ANALYSIS: Student's t test for unpaired data. RESULTS: Topical anaesthesia reduces the increase of intraocular pressure, hypertension and rate pressure product due to intubation. The intraocular pressure reduces to 13% less than basal value in Group L and increase to 50% more than basal value in Group F. CONCLUSION: The topical anaesthesia of larynx and trachea is effective to reduce the intraocular hypertension due to the reflex response evoked by orotracheal intubation. 相似文献
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AD Santin PL Hermonat JC Hiserodt J Fruehauf V Schranz D Barclay S Pecorelli GP Parham 《Canadian Metallurgical Quarterly》1997,64(3):477-480
Tumor cells from eight freshly isolated cervical cancers (i.e., four adenocarcinomas and four squamous carcinomas) were analyzed for their production of the immune-inhibitory cytokine transforming growth factor-beta (TGF-beta) in vitro. All fresh adenocarcinomas secreted significant levels of TGF-beta (mean 397, range between 207 and 782 pg/ml/10(5) cells/48 hr). In contrast, no detectable TGF-beta was present in the supernatants from the four fresh squamous carcinoma cultures (P < 0.001). These data suggest that major differences in the secretion of the immunoinhibitory cytokine TGF-beta exist between squamous cell carcinomas and adenocarcinomas of the uterine cervix. Furthermore, these findings suggest that at least some of the differences in the natural biologic behavior, as well as in the response to radiation treatment, between these two histologic types of cervical cancer could be related to differences in secretion of this immune-inhibitory cytokine. 相似文献
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OBJECTIVE: This study aimed to determine whether children continue to wear their cochlear implant systems 1 and 3 years after implantation. STUDY DESIGN: The design was a prospective study based on the analysis of forced-choice questionnaires on implant use completed independently by parents and teachers. SETTING: The study was performed at a dedicated pediatric cochlear implant program in a tertiary referral center in the United Kingdom. PATIENTS: All 85 consecutively implanted children who had reached the 1-year interval after implantation and 37 children who had reached the 3-year assessment interval after implantation participated. The patients represented all socioeconomic status groups, the entire range of educational settings, and often lived at a considerable distance from the implant center. MAIN OUTCOME MEASURES: Parents and local teachers were asked to describe implant use in the following categories: 1) all of the time; 2) most of the time; 3) some of the time; and 4) none of the time. RESULTS: One year after implantation, parents and teachers, respectively, rated 79 (93%) and 82 (96%) children as full-time users (category 1). Parents rated six children (7%) as users most of the time (category 2), and teachers rated three children (4%) as users most of the time. No child was rated as an occasional or nonuser (category 3 or 4). At 3 years after implantation, 33 (89%) and 34 (95%) children were rated as full-time users (category 1) by parents and teachers, respectively. Parents judged four children (11%) and teachers rated two children (5%) to be users most of the time (category 2). Again, no child was rated in category 3 or 4 as an occasional or nonuser. CONCLUSIONS: The majority of implanted children use their implant systems all of the time over a 3-year period after implantation when selected appropriately and given appropriate follow-up. 相似文献
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M Hafezparast CG Cole GP Kaur RS Athwal PA Jeggo 《Canadian Metallurgical Quarterly》1994,20(6):541-548
A hamster-human hybrid containing only the q arm of chromosome 2 has been used to construct a panel of hybrids bearing reduced regions of chromosome 2 using the technique of irradiation fusion gene transfer. The human chromosome 2 carried the Ecogpt gene and all hybrids were selected using this marker. The integrated Ecogpt gene was localized to the region 2q33-34, resulting in the selective retention of this region in the hybrids. These data were combined with another previously constructed panel of hybrids containing regions of 2q, which were enriched for the region 2q36-37. The combined hybrid panel is useful for the mapping of new markers to defined regions of chromosome 2 and for the cloning of genes located on 2q by a positional strategy. 相似文献
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GP Walsh 《Canadian Metallurgical Quarterly》1996,347(9016):1690-1691
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Ehrlichia spp. from human and equine sources in the northeastern Unites States were detected by PCR, isolated, and propagated in the HL-60 promyelocytic leukemia cell line. Growth of Ehrlichia from both equine and human sources was enhanced by addition of retinoic acid, which causes granulocytic differentiation of the HL-60 cells. DNA sequencing of a portion of the 16S rDNA gene supported the hypothesis that the same pathogen was responsible for both equine and human granulocytic ehrlichiosis. 相似文献