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51.
检测45例正常人和44例不同病期白血病血浆和外周血白细胞内维生素A、E、C、B12和β-胡罗卜素、叶酸浓度。结果表明,初治白血病患者血浆维生素A、β-胡罗卜素降低(P<0.01),未缓期解者血浆β-胡罗卜素和叶酸低于正常(P<0.01和P<0.05)。在初治和未缓解期患者的外周血白细胞内,维生素E、C、B12和β-胡罗卜素均显著降低(P<0.01~0.001)。而且,外周血白细胞内维生素代谢异常比血浆更为显著。提示维生素含量变化对于解释病因,预测疗效及估计预后有一定的价值。  相似文献   
52.
53.
KILL AND CURE THE HOPE AND REALITY OF VIRUS INACTIVATION   总被引:2,自引:0,他引:2  
  相似文献   
54.
The pharmacokinetics of reboxetine, a new antidepressant agent, were found to be close to linear in a crossover study comparing administration of single 2, 3, 4 and 5 mg capsule doses in 15 healthy male volunteers, and in the same study the capsules were bioequivalent to the proposed therapeutic tablet formulation (4mg). Kinetic analysis was based on HPLC assay of reboxetine in plasma and urine collected up to 72 h after each administration. Plasma levels indicated a rapid absorption (tmax?2h) and an elimination half-life of about 13 h. Clearance and volume of distribution were modest (ratios to bioavailability: CL/F?29 mL min?1; Vz/F?32L); urinary excretion was ~9% of dose, corresponding to a renal clearance of only 3 mL min?1 (a value consistent with the rate of glomerular filtration of unbound drug). In vitro, binding to plasma proteins, estimated from radioactivity levels following dialysis of 14C-labelled reboxetine, appeared to be dominated by α1-acid glycoprotein without marked saturation up to plasma concentrations of over 500 ng mL?1 (2.8–3.1% unbound with human plasma from three additional volunteers; 1.8–2.0% for 2gL?1 orosomucoid α1-acid glycoprotein, and 46.4–47.4% for 40 gL?1 albumin), whilst the mean Cmax in the current study was much lower (164 ng mL?1 after a 5 mg dose).  相似文献   
55.
目的 :探讨人精浆血管紧张素Ⅱ(AngⅡ)对精液常规指标的影响及其与男性不育症的关系。 方法 :通过固相提取 高效液相分离 放免法 (SPE HPLC RIA)测定 4 3例不育男性 (无精子症 13例 ,少弱精子症 8例 ,弱精子症17例 ,精液常规正常 5例 )和 10例正常生育男性对照组的血浆和精浆AngⅡ 。 结果 :精浆AngⅡ 水平明显高于血浆AngⅡ 水平 ,为血浆值的 3倍多 (P <0 .0 1) ;无精子症组精浆AngⅡ 浓度明显高于其他生育与不育男性 (P <0 .0 5 ) ;血浆、精浆AngⅡ与精子密度、活力、存活率、畸形率和精子顶体反应率等均无相关性。 结论 :精浆AngⅡ很可能由男性生殖道局部产生 ,除睾丸、附睾外 ,前列腺和 (或 )精囊也可能是其来源 ;无精子症病人精浆高AngⅡ 水平的原因及精浆AngⅡ在男性生育调节中可能发挥的具体作用 ,还需要进一步研究。  相似文献   
56.
Hexobarbital (HB) concentrations were determined in plasma and saliva of 8 healthy subjects, following oral administration of 500 mg HB-Na. Mean plasma half-lives were 3.2 +/- 0.1 h, and salivary half-lives 3.3 +/- 0.2 h. Mean plasma clearance was 22.9 +/- 2.3 1 h-1. There was a linear relationship between HB concentrations in saliva and plasma (r = 0.92). Mean salivary levels were 34 per cent of plasma levels. Salivary pH was constant throughout the experiment, 7.06 +/- 0.09. There was an inconsistent tendency of the saliva over plasma ratios to increase as a function of time. The percentage of protein binding calculated from saliva over plasma ratios was in reasonable agreement with in vitro data of equilibrium dialysis, 64.1 +/- 2.6 per cent and 65.9 +/- 0.8 per cent, respectively. The experiment was repeated in 4 subjects, and considerable intraindividual differences were shown to exist in saliva over plasma ratio, half-lives, and protein binding. It was concluded that HB elimination half-lives can relatively accurately be determined from salivary concentrations. Oral plasma clearance can only be estimated if the individual saliva over plasma ratios are known; this would require the taking of at least one blood sample during the experiment. When employing HB as a model substrate for drug metabolizing enzyme activity in vivo, the determination of its pharmacokinetic parameters, particularly oral plasma clearance as a reflection of cytochrome P-450 activity, cannot be achieved by taking saliva samples only.  相似文献   
57.
Summary The protein binding of furosemide was investigated in plasma from 22 old and 11 young subjects by equilibrium dialysis. The unbound fraction of furosemide was 3.16% in plasma from the elderly and 1.71% in plasma from the young. A significant correlation was found between the unbound fraction of furosemide and the plasma concentration of albumin. The average number of binding sites was 3.8 (elderly) and 2.7 (young) 10–6 mol/g albumin. The average association constant (K) was 4.3 (elderly) and 4.2 (young) 105 M–1. By increasing the concentration of furosemide up to 200 µg/ml buffer the unbound fraction of the drug rose to 5.2% (elderly) and 3.5% (young).  相似文献   
58.
Summary Slower drug absorption at night can leave residual drug from an evening dose of a sustained-release product remaining to be absorbed at the time of the next morning's dose, thereby giving higher plasma concentrations of the drug during the day than the night.When a capsule product releasing theophylline over 12 h after a morning dose was given repetitively at 8 a.m. and 8 p.m. for 4 days, daytime plasma concentrations from 4 h to 8 h after the dose were about 40% greater than corresponding night-time concentrations, and the mean steady-state concentration during the night-time interval was only 81% of that during the daytime interval.Altering the regimen to one capsule at 12 noon and one at 10 p.m. eliminated all significant differences between a.m. and corresponding p.m. plasma concentrations of theophylline and between the mean steady-state concentrations for each of the interdose intervals within a day.  相似文献   
59.
Bone marrow aspirates from 20 patients with multiple myeloma (MM), 4 with smoldering multiple myeloma (S-MM), 1 with idiopathic Bence Jones proteinuria (I-BJP), and 6 with primary macroglobulinemia (PMG) were examined for nucleolus-associated J chain. The incidence of nucleolar J chain-positive (J+) cells among nucleolated cells producing M-component was measured. This incidence (94.0-100%) in terminal MM was significantly higher than that (0-58.0%) in non-terminal MM. Judging from a low incidence in the remission phase, chemotherapy might cause a selective elimination of less differentiated myeloma cells with J+ nucleoli and might have some effect on J chain synthesis. The incidence of nucleolar J+ cells was very low in S-MM. The IgM cells in PMG, where J chain is present in a disulfide-linked form, had no or few J+ nucleoli. No correlation between the incidence of nucleolar J+ cells among nucleolated plasma cells and the percentage of nucleolated cells or that of J+ cells was found. Large J+ nucleoli seemed to be another morphological feature indicating anaplastic myeloma cells. A high incidence of nucleolar J+ cells may be one of the indicators for progressive disease.  相似文献   
60.
Abstract: The plasma ratio of each neutral amino acid (tryptophan (TRP), tyrosine (TYR), valine, isoleucine, leucine (LEU) or phenylalanine) to the sum of the other neutral amino acids was measured in 16 : manic and 14 : depressed patients. In the manics, there was a correlation between the psychomotor activity and the plasma TRP and LEU ratios. In the depressives, the depressed mood, retardation and global severity were correlated with the TRP ratio. The zotepine responders showed an increase in the TRP ratio after treatment. In the mianserin responders, the TYR ratio, which was high before the treatment, decreased to the normal range after the treatment. But, the plasma amino acid ratios remained unchanged in the patients treated with lithium carbonate or amitriptyhe. These results suggest that, in manic-depressive illness, there might be abnormalities in the metabolism of neutral amino acids, mainly of TRP and TYR, and that the plasma TRP and TYR ratios might be important indicators for determining the efflcacy of some drugs.  相似文献   
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