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61.
62.
B Goossens S Osaer S Kora KJ Chandler L Petrie JA Thevasagayam T Woolhouse J Anderson 《Canadian Metallurgical Quarterly》1998,142(11):277-281
An abattoir survey of sheep and goats was carried out in The Gambia for one year. A total of 1248 goats and 438 sheep, predominantly young females, were slaughtered and sampled. Sixty per cent of the females of both species were pregnant. There were no significant differences between the dressing percentages of different breeds and age groups. Sex and stage of pregnancy had a significant influence on carcase yields in both species. In goats the highest carcase yields were obtained during the early dry season. Most of the animals were clinically healthy and there were few pathological findings postmortem. In both species, there was a seasonal fluctuation of packed cell volume (PCV), with a minimum during the rains, and although the prevalence of trypanosomiasis was low it reduced the PCV. Faecal egg counts of Trichostrongylidae were highest during the rainy season and goats had higher faecal egg and coccidial oocyst counts than sheep. In sheep, a breed difference was observed for PCV and an age difference for egg excretion. The peak or higher rates of egg excretion occurred during the rains in both species. The immune status against peste des petits ruminants was significantly lower in goats (39 per cent) than in sheep (49.5 per cent). Antibodies against bluetongue virus were found in 62.6 per cent of goats and 55.8 per cent of sheep. 相似文献
63.
R van der Weide KJ Zuiderveld WP Mali MA Viergever 《Canadian Metallurgical Quarterly》1998,17(5):831-841
Coil embolization is a safe treatment for cerebral aneurysms only if the width of the neck in relation to the fundus of the aneurysm is small. Therefore, accurate visualization of the aneurysmal neck is required both in the diagnostic process and during the intervention. Conventional digital subtraction angiography (DSA) is still the preferred modality for the examination of cerebrovascular abnormalities like aneurysms, but it often does not provide the required morphological characteristics due to the suboptimal selection of projection angles and resulting overprojections of surrounding vasculature. This paper presents a method for performing a computer-assisted calculation of the optimal projection angles for DSA by post-processing computed tomographic angiography (CTA) volume data using ray-casting techniques and a combination of image processing algorithms. By means of phantom studies, retrospective simulations of angiograms, and in vivo applications of calculated optimal viewing angles, it is demonstrated that the proposed method results in better angiographic projections of the neck of saccular aneurysms with small neck-fundus ratio than those acquired at standard angles prescribed by clinical protocols. 相似文献
64.
Bcl-xL functions downstream of caspase-8 to inhibit Fas- and tumor necrosis factor receptor 1-induced apoptosis of MCF7 breast carcinoma cells 总被引:1,自引:0,他引:1
A Srinivasan F Li A Wong L Kodandapani R Smidt JF Krebs LC Fritz JC Wu KJ Tomaselli 《Canadian Metallurgical Quarterly》1998,273(8):4523-4529
Stimulation of the Fas or tumor necrosis factor receptor 1 (TNFR1) cell surface receptors leads to the activation of the death effector protease, caspase-8, and subsequent apoptosis. In some cells, Bcl-xL overexpression can inhibit anti-Fas- and tumor necrosis factor (TNF)-alpha-induced apoptosis. To address the effect of Bcl-xL on caspase-8 processing, Fas- and TNFR1-mediated apoptosis were studied in the MCF7 breast carcinoma cell line stably transfected with human Fas cDNA (MCF7/F) or double transfected with Fas and human Bcl-xL cDNAs (MCF7/FB). Bcl-xL strongly inhibited apoptosis induced by either anti-Fas or TNF-alpha. In addition, Bcl-xL prevented the change in cytochrome c immunolocalization induced by anti-Fas or TNF-alpha treatment. Using antibodies that recognize the p20 and p10 subunits of active caspase-8, proteolytic processing of caspase-8 was detected in MCF7/F cells following anti-Fas or TNF-alpha, but not during UV-induced apoptosis. In MCF7/FB cells, caspase-8 was processed normally while processing of the downstream caspase-7 was markedly attenuated. Moreover, apoptosis induced by direct microinjection of recombinant, active caspase-8 was completely inhibited by Bcl-xL. These data demonstrate that Bcl-xL can exert an anti-apoptotic function in cells in which caspase-8 is activated. Thus, at least in some cells, caspase-8 signaling in response to Fas or TNFR1 stimulation is regulated by a Bcl-xL-inhibitable step. 相似文献
65.
GL McIntire ER Bacon JL Toner JB Cornacoff PE Losco KJ Illig KJ Nikula BA Muggenburg L Ketai 《Canadian Metallurgical Quarterly》1998,87(11):1466-1470
Lung cancer continues to be a leading cause of death around the world. Staging of this disease is critically dependent upon the involvement or noninvolvement of the lymph nodes which drain the region of lung containing the lesion/tumor. Palpation, unenhanced CT, and lymph node excision (i.e., mediastinectomy) are currently used to ascertain the status of these regional draining lymph nodes. The work reported herein details the first efforts toward the pulmonary instillation of iodinated nanoparticles for contrast-enhanced CT of lung draining lymph nodes. The data reflect the impact of dose, time post instillation, and formulation (surfactant) upon the observed CT enhancement of the tracheobronchial lymph nodes of beagle dogs. In addition, initial safety is discussed with both macroscopic and microscopic observations. The results indicate that pulmonary instillation of small volumes of iodinated nanoparticles could be successfully used to aid staging of lung cancer by CT imaging. 相似文献
66.
The chondro-osseous junction has been the subject of considerable scrutiny, especially in terms of the fate and role of the terminally differentiated chondrocyte. Although it has been proposed that these cells change their phenotype and survive in the epiphysis, possibly as osteoblasts, evidence from a number of other studies suggests that chondrocytes may undergo apoptosis or programmed cell death. A useful test for programmed cell death is to end label DNA in cryosections using the commercial reagent ApopTag and detect antibody binding to fragmented DNA by epifluorescence; more direct assessments include examination of the nucleus for condensation of chromatin evaluating fragmentation through alkaline and pulsed field agarose gel electrophoresis of DNA, and measuring apoptosis by flow cytometry. We found that we could label cells in the proliferative and the hypertrophic region of the proximal tibial growth plate of the chick with ApopTag. Most of the chondrocytes in the hypertrophic region were labeled by the reagent; in contrast, few proliferative chondrocytes were stained by the end-labeling procedure. Both agarose and pulsed field electrophoresis were used to confirm that there was fragmentation of chondrocyte DNA. Alkaline gel electrophoresis indicated that there was more fragmentation of DNA from hypertrophic cells than from proliferative chondrocytes. Further evidence in support of apoptosis was provided by electron microscopic observation of cells in the hypertrophic region of the growth plate. We noted that many of the cells in this region of the growth plate appeared to be undergoing programmed cell death since their nuclei contained condensed chromatin. Finally, we used flow cytometry to analyze chondrocytes isolated from the proliferating and hypertrophic regions of the growth plate for apoptosis. Dual parameteric flow cytometric contour plots of Hoechst and 7-amino-actinomycin D fluorescence showed that abut 8% of cells in the plate were apoptotic. Most of these cells were in hypertrophic cartilage. In summary, the results of this investigation indicate that chondrocytes terminate their life history by apoptosis. While it is possible that the terminal labeling studies may overestimate the number of cells undergoing this event, the data lend credence to the view that cells are removed from the epiphysis through apoptosis. If this is the case, then chondrocytes probably enter the terminal phase of their life as fully functioning cells and genomic, and/or local environmental conditions provide termination signals that initiate events that lead to programmed cell death. 相似文献
67.
The outcomes of seven patients with severe comminuted intraarticular fractures of the distal radius treated by arthroscopic reduction and percutaneous external fixation (ARPEF) were retrospectively reviewed. All of the fractures were classified as C3 types using the AO classification scheme. Outcomes were evaluated using the Gartland and Werley functional criteria, an objective wrist examination, a radiographic analysis, and a self-assessment outcome form at an average follow-up of 27 months (range, 12 to 45 months). All patients were free of pain and had returned to their prior occupations. No patient had articular incongruency of greater than 1 mm, and there was no evidence of radiocarpal degenerative change. Active range of motion and maximal grip strength averaged 92% and 98%, respectively, of the uninjured wrist. The technique of arthroscope-assisted reduction and percutaneous external fixation yielded excellent results in a small group of patients, with minimal complications. 相似文献
68.
69.
Ulnohumeral arthrodesis is the standard technique for elbow fusion. The geometry and surface area of the distal humerus and proximal ulna enhance the chances of fusion while maintaining some wrist motion. A case of a patient with multiple failed elbow procedures in which the standard ulnohumeral fusion was not possible is presented. A radiohumeral arthrodesis was performed in an attempt to obtain a stable, nonpainful elbow. After complete healing of the fusion, the patient was able to use the arm for most functions. This technique is presented as an option for salvage failed elbow arthroplasty in the face of significant bone loss. 相似文献
70.
HJ Schulze HP Wendel M Kleinhans S Oehmichen H Guggenberger W Heller HE Hoffmeister 《Canadian Metallurgical Quarterly》1998,13(5):338-345
Perioperative haemodynamic changes leading to severe circulatory problems during open-heart surgery still represent dreaded complications. The aim of this study was to examine the relationship between the use of applied anaesthetic agents and alterations of the contact phase of the intrinsic blood-clotting system, as changes within the kallikrein-kinin system can lead to a fall in blood pressure. In a randomized study, parameters of the kallikrein-kinin system, coagulation and fibrinolysis were determined for 36 patients with aortocoronary bypass operations. The patients had been given either midazolam/fentanyl or propofol/alfentanil to maintain anaesthesia. Perioperative blood pressure values were registered at seven fixed points. The measured values of the factor XIIa-like activity and the kallikrein-like activity suggested a higher activation of the contact phase, when propofol/alfentanil was given. From the start of the extracorporeal circulation (ECC) to the end of the operation, the kallikrein-like activities in the propofol/alfentanil group were significantly higher than those of the midazolam/fentanyl group. Also, the results of the kallikrein inhibition capacity and the indicators of fibrinolysis (t-PA and D-dimers) indicate a stronger activation of the contact phase--at least at the beginning of recirculation--and as a result of it, a stronger fibrinolysis within the propofol/alfentanil group. In addition, the hypotensive side-effects differed significantly between the two groups. Patients receiving propofol/alfentanil needed the triple amount of antihypotonicum to maintain the mean arterial blood pressure above 75 mmHg. With the results of this study, a correlation between the application of propofol/alfentanil, contact phase activation, with activation of the kallikrein-kinin-bradykinin system and the observed hypotension, can be presumed. 相似文献