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41.
42.
H Hebart D Gamer J Loeffler C Mueller C Sinzger G Jahn P Bader T Klingebiel L Kanz H Einsele 《Canadian Metallurgical Quarterly》1998,36(5):1333-1337
Murex hybrid capture DNA assay (HCS) is a solution hybridization antibody capture assay for detection and quantitation of cytomegalovirus (CMV) DNA in leukocytes. To determine whether CMV HCS is sensitive enough to initiate and monitor antiviral therapy after allogeneic stem cell transplantation (SCT), 51 consecutive SCT recipients were prospectively screened for the appearance of CMV infection by HCS, PCR, and culture assays from blood samples. Preemptive antiviral therapy was initiated after the second positive PCR result in all patients, as previously reported, and HCS was not considered for clinical decision making. A total of 417 samples were analyzed. Of these, 21 samples were found to be positive by PCR and HCS, 88 samples were PCR positive but HCS negative, and 308 were negative by both assays. Concordance of results between PCR and HCS and between HCS and blood culture was observed in 78.9 and 95.9% of the samples assayed, respectively. PCR was found to be more sensitive than HCS, and HCS was more sensitive than the blood culture assay (P < 0.0001). Four patients with symptomatic CMV infection were PCR positive prior to the onset of CMV-related symptoms, whereas HCS detected CMV DNA in three patients prior to and one at onset of CMV disease. The numbers of genomes per milliliter of blood were higher in patients with symptomatic CMV infection than in those with asymptomatic CMV infection (P = 0.06). None of the HCS-negative patients developed CMV disease. Thus, all patients with CMV disease were correctly identified by HCS; however, the lower sensitivity limit of the HCS assay may still be insufficient to allow diagnosis of CMV infection early enough to prevent CMV disease in patients following allogeneic SCT. 相似文献
43.
Christoph Wolff Frank Ulrich Briegleb Joerg Bader Klaus Hektor Hans Hammer 《化学工程与技术》1990,13(1):172-184
Many experimental studies reveal that suspended solids considerably alter the coalescence behaviour and hydrodynamic functions of wo-phase flow. But no systematic efforts have yet been undertaken to separate the effects of different particle properties on local gas hold-up, bubble size and interfacial area gas/liquid. The aim of this paper is to present the local values of these parameters in three-phase fluidized beds of different solids, using miniaturized optical fiber and conductivity needle probes. It is shown that particle concentration, size and, in particular, density are decisive for the change in coalescence behaviour. Ranges of normal (?S > ?L) and inverse fluidization (?S < ?L) must be distinguished and the flow regime also exerts a strong influence on the interactions between the dispersed phases, the transition point itself being a function of particle properties can be observed, This effect is evaluated for different column diameters, between 0.1 and 0.3 m. 相似文献
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45.
AIMS: The pharmacokinetics of intramuscular artemether and its major plasma metabolite-dihydroartemisinin, were investigated in patients with severe manifestations of falciparum malaria. METHODS: Six severe falciparum malaria patients with acute renal failure (ARF) and 11 without ARF were recruited into the study. They were treated with intramuscular artemether at a loading dose of 160 mg, followed by daily doses of 80 mg for another 6 days (total dose 640 mg). RESULTS: Patients with and without ARF showed a good initial response to treatment; the parasite and fever clearance times were 66(30-164) and 76(36-140) h [median(range)], respectively. None had reappearance of parasitaemia in their peripheral blood smear within 7 days of initiation of treatment. In comatose patients, the time to recovery of consciousness was 51.6(22-144) h. Artemether was detected in plasma as early as 1 h after a 160 mg dose, and declined to undetectable levels within 24 h in most cases. Patients with ARF had significantly higher Cmax [2.38(1.89-3.95) vs 1.56(1.05-3.38) ng ml(-1) mg(-1) dose], AUC [35.4(22-52.9) vs 25.2(13.4-52.9) ng ml(-1) h mg(-1) dose], and lower Vz/F [5.45(3.2-6.9) vs 8.6(4.2-12.3) l kg(-1)] and CL/F [7.4(5.4-13.8) vs 19.1(8.5-25.1) ml min(-1) kg(-1)] when compared with those without ARF. In addition, t1/2,z was significantly longer in ARF patients [7.0(5.5-10.0) vs 5.7(4.2-6.6) h]. The pharmacokinetics of dihydroartemisinin in the two groups of patients were comparable. CONCLUSIONS: ARF significantly modified the pharmacokinetics of intramuscular artemether. The changes could be attributed to either improved absorption/bioavailability, a reduction of systemic clearance, or a change in plasma protein binding of the drug. 相似文献
46.
M Bader 《Canadian Metallurgical Quarterly》1998,31(9):1171-1183
The interplay of vasoactive peptide systems is an essential determinant of blood pressure regulation in mammals. While the endothelin and the renin-angiotensin systems raise blood pressure by inducing vasoconstriction and sodium retention, the kallikrein-kinin and the natriuretic-peptide systems reduce arterial pressure by eliciting vasodilatation and natriuresis. Transgenic technology has proven to be very useful for the functional analysis of vasoactive peptide systems. As an outstanding example, transgenic rats overexpressing the mouse Ren-2 renin gene in several tissues become extremely hypertensive. Several other transgenic rat and mouse strains with genetic modifications of components of the renin-angiotensin system have been developed in the past decade. Moreover, in recent years gene-targeting technology was employed to produce mouse strains lacking these proteins. The established animal models as well as the main insights gained by their analysis are summarized in this review. 相似文献
47.
The wetting angle of sodium on different pure metals (Ni, Ta, Mb, Mo, W), alloys (stainless steel 304L, Inconel 600, RTG 36, TZM) and oxides (Feldmühle E37, Degussa AL23, sapphire, ZrO2, Y2O3) was measured in the temperature range from 520 to 720°C. A new measurement method was applied consisting of a combination of the classical sessile drop with a gas controlled heat pipe. The method is especially suited for high temperatures where the previous methods are impracticable because of excessive sodium evaporation. It has furthermore the advantage that the measurements are made under pure sodium vapour. In the temperature range mentioned all investigated materials are well wetted. The maximum measured wetting angle is 7.5°. The wetting angles are nearly independent from temperature, but they show a time-dependency consisting in general of a rapid initial decrease and a reaching of the equilibrium value after about 1 hour. 相似文献
48.
The anneal hardening behavior of a Cu-16 at. pct. Al alloy was investigated by tensile testing, measurement of Young’s modulus
and electrical resistivity, and electron microscopy. It was shown that three main stages of annealing processes can be distinguished.
Stage 1 atT ≤ 150°C is characterized by vacancy annihilation and short-range diffusional processes giving rise to three successive, low
maxima in yield and tensile strength. Substages in this temperature range are also evident from resistivity measurements.
Stage 2 at 150 ≲ 275°C is essentially associated with solute segregation to dislocations giving rise to the main increase
in flow stress. In Stage 3 at 725 ≤T ≤ 350°C recrystallization takes place. 相似文献
49.
Gentamicin sulfate was given to rabbits for four weeks in two dosage regimens, either 4 or 8 mg/kg subcutaneously twice a day. Two of the seven animals in each group regained nearly normal renal function after a transient rise in the level of serum creatinine, but the remainder developed severe renal failure leading to the death of all but one of these rabbits. None of the animals showed significant hyperglycemia, buy glycosuria appeared in all and was significantly correlated with the extent of renal damage. These findings demonstrate gentamicin-induced derangement of proximal tubular function and thus amplify the previously demonstrated histologic changes due to the drug. When the drug was administered twice daily, there was marked nephrotoxicity in rabbits given dosages of gentamicin only slightly higher than those employed clinically. 相似文献
50.