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991.
BD Sippy FM Hofman AD Wright S He SJ Ryan DR Hinton 《Canadian Metallurgical Quarterly》1996,63(3):311-317
Tumor necrosis factor-alpha (TNF) has been implicated in the pathogenesis of several retinal diseases. Soluble forms of the TNF receptors, p55 (55 kDa) and p75 (75 kDa), have recently been identified in biological fluids and may regulate TNF activity. The potential biological significance of these receptors for the human retina was examined by determining their presence in human vitreous and their release from eye cup explants in which the retina has been removed leaving an intact retinal pigment epithelium (HRPE). Normal human vitreous and conditioned medium from eye-cup HRPE explants demonstrated the presence of soluble p55 and p75. Soluble p55 was significantly more abundant than p75 in all vitreous samples (P < 0.03). Conditioned medium from eye-cup HRPE explants contained significantly more soluble p55 than p75 (P < 0.00002). Enzyme-linked immunosorbent assay showed the presence of soluble p55, and not p75, in conditioned medium from primary cultured HRPE cells. Activation of the protein kinase C pathway in these cells with the phorbol ester PMA significantly increased the release of soluble p55 (P < or = 0.001); whereas, pharmacological inhibition of protein kinase C with calphostin-C significantly decreased the shedding of p55 (P < or = 0.001). The results indicate that primary cultured HRPE cells shed p55 and regulate this shedding in part through the protein kinase C pathway. The presence of soluble TNF receptors within normal human vitreous and within conditioned medium from the eye-cup HRPE explant model suggests that these soluble receptors may have a biological function in the eye. 相似文献
992.
Part II of this paper gives the results of applying the TBI methods described in part I, to in vivo patient planning and dosimetry. Patients are planned on nine CT based body slices, five of which pass through the lungs. Planned doses are verified with ten silicon diodes applied bi-laterally to five body sites, at each treatment. LiF TLDs are applied to seven other body sites at the first treatment only. For 84 patients and at least 1016 measurements per body site with the diodes, the mean measured total doses agreed with planned doses within at most 2% except at lung levels, where the mean measured dose was 3% too low. Standard deviations of the measurements about the mean were between 2.4 and 3.1%. For the LiF TLDs, the mean measured doses for all seven body sites were with in +/- 5% of planned doses. A separate assessment of measured entrance and transmitted doses showed that the former agreed well with planned doses, but that the latter tended to be low, especially over the lungs, and that they had a wider dispersion. Possible reasons for this are discussed. These results show measurement uncertainties similar to those for non-TBI treatments of Nilsson et al, Leunens et al and Essers et al. An analysis of the treatment plans showed a mean dose inhomogeneity in the body (75 patients, nine slices) of 19 +/- 6.0% (1 s.d.) and in the lungs (40 patients, five slices) of 9.2 +/- 2.85% (1 s.d.). The conclusions are that, overall, the methods are reasonably satisfactory but that, with an extra effort, even closer agreement between measured and planned doses and a further limited reduction in the body dose inhomogeneity could be obtained. However, if it were thought desirable to make a substantial reduction in the dose inhomogeneity in the body and lungs, this could only be achieved with the available equipment by changing from lateral to anterior-posterior irradiation and any potential advantages of this change would have to be balanced against a likely deterioration in patient comfort and an increase in treatment set-up times. 相似文献
993.
R Laird Pérez E Ramírez Fernández U del Risco Barrios FM Crespo Alvarez MC Dona López 《Canadian Metallurgical Quarterly》1996,51(3-4):97-100
Control of quality of coproparasitological diagnosis was carried out in the Province "Las Tunas", between January and March 1993, It was found that 72% of coproparasitological microscopists had deficiencies related to the diagnosis, due to several causes: The microscopists did not receive any periodical training, as they did not participate at the parasitological section; the microscopists had no manual of reference; they had less than ten years of experience; they did not know the concentration technics that were established in the country. Between July 1993 and January 1994 two Medical Parasitology Courses were imparted. In July 1994 another quality control was performed. 80% of evaluated microscopists obtained good results. Through this study was established the National Parasitology Quality System Control that supports the National Intestinal Parasites Control Program. 相似文献
994.
DA Alymkulov FM To?chieva GM Saralinova LF Le?kina 《Canadian Metallurgical Quarterly》1996,112(2):13-15
A corneal oblique incision running along the chord relative to the limbus has been developed, which enables to finish an operation without suturing the incision. A reliable union of the incision edges is attained after air injection to the anterior chamber, the incision being no more than 5 or 5.5 mm. The incision was used in 72 clinical operations for extraction of congenital, secondary, and traumatic cataracts. The shape of incision, absence of sutures and additional injury caused by removal of sutures helped reduce the postoperative astigmatism and brought about good functional results. 相似文献
995.
FM Mims 《Canadian Metallurgical Quarterly》1996,64(5):814-816
We report six caucasian patients who had acute pain in the hip and marked limitation of all movement of the joint. Plain radiographs and CT of the pelvis showed calcification within the reflected head of rectus femoris. All six responded to accurate CT-controlled injections of corticosteroid and local anaesthetic with dramatic and prolonged pain relief, although one required a second injection for recurrence of symptoms after two months. 相似文献
996.
OBJECTIVE: To study the role of chromosomal aberration in the causation of recurrent spontaneous abortion (RSA) in Chinese population. METHODS: A total of 514 Chinese couples with 2 or more spontaneous abortions at less than 24 weeks of gestation were included. For each proband, a minimum of 13 metaphases were analyzed by G-banding. Additional cells (usually 50-100 cells) were screened when mosaicism was suspected. Chi 2 test was used to compare the number and frequency of couples with and without balanced translocation with respect to whether liveborn was present or absent. Chi 2 test for trend was used to show whether a correlation existed between the occurrence of balanced translocation and the number of spontaneous abortions at ascertainment. RESULTS: The overall incidence of chromosome anomaly was 51 out of 514 (9.92%). Chi 2 test for trend analysis showed that the chance of one member of a couple being a balanced carrier increased with the number of spontaneous abortions. The chance of finding translocation in couples with liveborn was higher than that in couples without liveborn, but the difference was not statistically significant. We also found that pericentric inversion 9 did not play an important role in the causation of recurrent abortion. CONCLUSIONS: Cytogenetic analysis is indicated in couples with 2 or more spontaneous abortions and the chance of finding chromosomal aberration increases with the number of abortions at the time of ascertainment. 相似文献
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This article estimates and evaluates the economic impacts from a catastrophic earthquake within regional and national contexts,
emphasising the inter-industry relationship in conjunction with regional commodity flows and the assessment of seismic damages
on a transportation network. The analytical methods employed are twofold: a multi-regional input-output model and a regional
commodity flow model. Using the above analytical framework, the economic impacts from a catastrophic earthquake are estimated
and evaluated based on hypothetical scenarios of the event, by analysing the magnitude and extent of direct and indirect impacts.
Furthermore, as possible extensions, the models developed here can be used as tools for strategic management of the recovery
and reconstruction efforts after the event.
Received: 24 September 2000 / Accepted: 23 May 2001 相似文献