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991.
E Katunguka-Rwakishaya JJ Parkins G Fishwick M Murray PH Holmes 《Canadian Metallurgical Quarterly》1995,59(3-4):207-218
The intensity of parasitaemia, degree of anaemia, live body weight gains and blood biochemical changes were measured in two groups of Scottish Blackface sheep infected experimentally with Trypanosoma congolense and allowed either a high (9.9 MJ metabolisable energy (ME) day-1) or a low (6.1 MJ ME day-1) energy intake. It was observed that infected animals on the low energy intake had a longer mean prepatent period, but following patency they developed more severe anaemia and greater growth retardation than those on the high energy intake. Both infected groups exhibited significant reductions in serum total lipids, phospholipids, plasma cholesterol and albumin. However, these changes were more severe in the animals on the low energy intake than in those on the high energy intake. It was concluded that adequate energy nutrition enhances the ability of infected animals to withstand the adverse effects of infection, by promoting body weight gains and moderating the severity of the pathophysiological changes associated with ovine trypanosomosis. 相似文献
992.
Realization of novel low-loss monolithically integrated passive waveguide mode converters 总被引:1,自引:0,他引:1
B.M. Holmes D.C. Hutchings 《Photonics Technology Letters, IEEE》2006,18(1):43-45
The novel design and fabrication of monolithically integrated passive waveguide mode converters (WMCs), realized through the utilization of the reactive ion-etch lag (RIE Lag) phenomenon, is reported. The low-loss GaAs-AlGaAs WMCs have been characterized over a wavelength range of 900-940 nm, resulting in TE-TM (TM-TE) mode conversion with efficiencies of greater than 96% and low-loss devices with conversion lengths as short as 150 /spl mu/m. The properties and characteristics of the fully integrated WMCs, fabricated with a single masking and etch process, are in agreement with theoretical predictions. 相似文献
993.
JA DiPaolo CD Woodworth F Coutlée DB Zimonic J Bryant A Kessous 《Canadian Metallurgical Quarterly》1998,76(6):865-871
Transfection of the right end Xho2 subfragment of Bg/II N of herpes simplex virus-2 (HSV-2) into human genital keratinocytes immortalized by human papillomavirus (HPV) type 16 or 18 resulted in invasive and noninvasive indolent cystic squamous carcinomas when cells were injected into immunocompromised mice. Retention and expression of the right end portion of the Bg/II N fragment correlated with malignancy, as the corresponding HSV-2 sequences were integrated and transcribed in the tumorigenic cell lines. HPV-immortalized cells alone were not tumorigenic. In contrast, previous results have shown that using the entire Bg/II N region can malignantly transform HPV-immortalized cells, although HSV2 DNA was not retained. Together, these observations localize the transforming activity of Bg/II N to Xho2 and suggest that the remaining sequences have an inhibitory effect on stable integration. The Xho2 sequence is 2480 bp long and contains an open reading frame (ORF) extending from nucleotides 559 to 1797. The ORF encodes a putative protein of 412-aa with a m.w. of 42-43 kDa and is highly homologous to UL43 of HSV-I. The correlation of tumorigenicity with stable integration and expression of Xho2 DNA in HPV-immortalized cells indicates that HSV-2 should be investigated further for a possible role in cervical cancer. 相似文献
994.
SB King W Yeh R Holubkov DS Baim G Sopko P Desvigne-Nickens DR Holmes MJ Cowley MG Bourassa J Margolis KM Detre 《Canadian Metallurgical Quarterly》1998,31(3):558-566
OBJECTIVES: We sought to compare outcomes of patients treated in the National Heart, Lung, and Blood Institute (NHLBI) Percutaneous Transluminal Coronary Angioplasty (PTCA) and New Approaches to Coronary Intervention (NACI) registries. BACKGROUND: Coronary angioplasty has numerous shortcomings. New devices for performing coronary interventions have been introduced in an effort to improve clinical outcomes. METHODS: Under the sponsorship of the NHLBI, a registry of consecutive patients treated with PTCA during 1985 to 1986 was established. In 1990, the NHLBI funded a second registry, the NACI. The two registries used the same data coordinating center to collect detailed baseline and follow-up information. RESULTS: Patients enrolled in the NACI registry were older, had undergone more previous bypass surgery procedures and had more stenoses located in bypass grafts than patients in the NHLBI PTCA registry. Procedural success was achieved in 72.1% and 82.6% of patients in the PTCA and NACI registries, respectively; however, in-hospital and 1-year mortality rates were 1.0% versus 1.8% and 3.1% versus 5.9% for the PTCA versus NACI registries, respectively. After risk adjustment, there was no difference in 1-year mortality. Rates of target lesion revascularization (TLR) were 21.5% for the PTCA registry and 24.2% for the NACI registry. NACI registry patients had a higher risk for TLR and the composite end point of death, myocardial infarction or revascularization (relative risk 1.28 and 1.23, respectively). However, the NACI registry patients who received stents tended to have a lower adjusted TLR rate. CONCLUSIONS: This comparative study found no overall superiority of these newer devices in terms of patient survival or freedom from TLR after adjustment for baseline risk profiles. Although technologic improvements (especially improved stenting) continue, these observations highlight the importance of careful assessment of clinical results in the broad population of patients in whom interventions are used. 相似文献
995.
996.
997.
Malcolm Glennie Holmes 《Journal of the Institute of Brewing》1995,101(1):11-18
Rapid Viscoanalysis was investigated as a method off determining the malting quality of barley and malt, to define the conditions required to select progeny with high malting potential from a barley breeding programme. Studies were made on (i) varying physical parameters and chemical additions, (ii) the effect of modification, (iii) the prediction of malting potential from viscograms, (iv) the relationship of the viscometric characteristics of starch to malting quality and (v) the use of a Rapid Viscoanalyser (RVA) in a commercial meltings. The results will be presented as a series of papers. In this paper, physical and chemical factors were examined. Firstly, sample/liquid ratios, initial and final temperatures, speed off mixing and the fineness of grinding of the samples were varied. The effect of the time of standing of malt slurries was also investigated. The peak areas, peak viscosities and Stirring Numbers were shown to obey a relationship with the cube of the sample concentration under a wide range of conditions. Comparisons with the Amylograph and Falling Number Apparatus are reported. Conditions of grinding, temperature, speed of mixing and grist/liquid ratios for the routine examination of barleys and malts were defined. Secondly, calcium-complexing agents, acids, alkalies and the salts of heavy metals were tested for their effects on the Rapid Viscogram of malt. Unless substantial time was allowed for reaction to occur, calcium-complexing agents per se had no effect on viscograms: acidic radicles were necessary. Although both acids and alkalies affected viscograms, inhibition could be reversed by neutralisation. Silver nitrate is suggested as the most suitable chemical for inhibition of enzymes for the determination of the intrinsic viscosity of malts with an RVA. 相似文献
998.
JS Mruk P Zoldhelyi MW Webster M Heras DE Grill DR Holmes V Fuster JH Chesebro 《Canadian Metallurgical Quarterly》1996,93(4):792-799
BACKGROUND: Thrombolysis to normal flow in patients with acute myocardial infarction preserves left ventricular function and decreases mortality. Failure of early reperfusion, reocclusion, or residual thrombus may be due to concurrent activation of the platelet-coagulation system. Thus, we hypothesized that the best concomitant antithrombotic therapy (recombinant [r]-hirudin, heparin, or aspirin) will maximally accelerate thrombolysis by r-tissue-type plasminogen activator (rTPA) and reduce residual thrombus. METHODS AND RESULTS: Occlusive thrombi were formed in the carotid arteries of 29 pigs (by balloon dilatation followed by endarterectomy at the site of injury-induced vasospasm) and matured for 30 minutes before rTPA was started, with or without antithrombotic therapy. Thrombolysis was assessed with the use of angiography and measurement of residual thrombus. Pigs were allocated to one of five treatments: placebo, rTPA, rTPA plus r-hirudin, rTPA plus heparin, or rTPA plus intravenous aspirin. No placebo-treated pig reperfused. Two of six animals treated with rTPA alone reperfused compared with seven of seven animals treated with rTPA plus r-hirudin (reperfusion time, 33 +/- 10 minutes), six of seven animals treated with rTPA plus heparin (reperfusion time, 110 +/- 31 minutes), and two of six animals with rTPA plus aspirin. The activated partial thromboplastin time was prolonged in only the rTPA plus r-hirudin group (25 +/- 0.1 times baseline) and the rTPA plus heparin group (5.3 +/- 0.2 times baseline). Residual 111In-platelet and 125I-fibrin(ogen) depositions were lower in the heparin-treated group and lowest in the r-hirudin-treated group (heparin versus hirudin, respectively; incidence of residual macroscopic thrombus was six of six animals versus two of seven [P = .01]; 125I-fibrin(ogen), 170 +/- 76 versus 48 +/- 6 x 10(6) molecules/cm2 [P = .02]; 111In-platelets, 47 +/- 15 versus 13 +/- 2 x 10(6)/cm2, P = .10). No pigs developed spontaneous bleeding. CONCLUSIONS: Thrombin inhibition with heparin or r-hirudin significantly accelerated thrombolysis of occlusive platelet-rich thrombosis, but only the best antithrombotic therapy (r-hirudin) eliminated or nearly eliminated residual thrombus. 相似文献
999.
IL Wapnir H Southard G Chen J Friedman CD Boyd PS Amenta 《Canadian Metallurgical Quarterly》1996,16(6):308-316
Excessive deposition of extracellular matrix or neomatrix is a characteristic of desmoplastic invasive breast carcinomas. Type I and III collagens are abundant neomatrix components. Archival breast tissue sections were studied using 35S-labeled cDNA probes for alpha 1(I) and alpha 1(III) procollagen and in situ hybridization. Among the 33 invasive breast cancers, hybridization was seen forming a gradient-like pattern in fibroblasts closest to tumor cells. In the 10 ductal carcinomas in situ studied, a ring-like pattern of hybridization was seen in proximity to the basement membrane zone. Adjacent normal and benign tissues did not demonstrate the patterns of hybridization described in malignant tissues. Gene expression for neomatrix interstitial collagens occurs before there is evidence of invasion in carcinoma of the breast. 相似文献
1000.
BACKGROUND: Adult-onset minimal-change nephropathy has been associated with a slower response to corticosteroids and a less benign prognosis when compared to children. However, there are few long-term outcome data reported. METHODS: We have reviewed retrospectively 51 idiopathic adult-onset minimal-change nephropathy patients investigated and treated at a single centre. RESULTS: Male to female ratio was 1:1.4, mean age at diagnosis was 37 years, and average length of follow-up was 14.1 years. Significant comorbidity was identified in 33%. A raised serum creatinine was found in 55% but returned to normal almost invariably upon remission. At presentation, hypertension was found in 47% of patients, microscopic haematuria in 33%, hypercholesterolaemia and hypertriglyceridaemia in 96%, and hyperuricaemia in 42%. Remission (complete or partial) was achieved by 46, 70 and 92% within 4, 8 and 21 weeks respectively, in patients treated with steroids; steroid resistance was encountered in 8%. The time to remission was positively correlated with age (P = 0.002) and initial albumin level (P = 0.005), and negatively correlated to the number of subsequent relapses (P = 0.029); 33% of patients had a spontaneous remission at some time during the disease course. Patients with multiple relapses were treated with cyclophosphamide and 63% of them had remained in remission after 5 years. Hypertension was present in 25% of patients after an average interval of 11 years. At the time of the final follow-up, only three patients had a raised creatinine and all but three patients were in complete remission. CONCLUSIONS: Adult-onset minimal-change nephropathy shares the same good long-term outcome as the childhood counterpart, with sustained remission and preserved renal function. 相似文献