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41.
AM Mingers 《Canadian Metallurgical Quarterly》1976,123(3):199-213
Factor VIII exchange test experiments with hemophilia A plasmas were performed to find out how the results were affected by submitting plasmas and plasma mixtures to different incubation periods at 37 degrees C, heat precipitation, and ether extraction. The experiments led to the following results: 1. In plasma mixtures, frequently higher factor VIII activities are found than can be expected from the single activities of the used plasmas. Activity increases are factor-specific. 2. The component to be activated is in the hemophilic plasma; the activity-increasing agent is in the normal plasma. These results lead to the hypothesis that hemophilia A patients have sufficient quantities of inactive factor VIII, but it stays inactive for lack of the necessary activator. In normal plasma the activator is in balance or surplus to the inactive factor. By adding normal plasma, thus supplying free activator, the inactive factor VIII of hemophilia A plasma can, under suitable conditions, be developed into active factor VIII. 相似文献
42.
Binary mixtures of weak and strong UV-absorbing alkaloids were analyzed by a charge-transfer spectrophotometric method, utilizing iodine in ethylene dichloride as the acceptor. In the uncomplexed form, the strong absorbing alkaloid (papaverine, quinine, ergotamine, or reserpine) was measured at a wavelength where there was no interference from weak absorbers (at 335, 332, 315, or 300 nm, respectively). The weak absorbing alkaloid (ephedrine, codeine, atropine, or homatropine methylbromide) was determined by computing its contribution to the total charge-transfer band at 295 nm where absorbance was linearly additive for mixtures. The greater increase in the original epsilon-values of the weak absorbers upon complexation with iodine relative to the corresponding increase in the epsilon-values of the strong absorbers led to good recoveries even at the low dose ratios of the weakly absorbing, and often more potent, alkaloids. 相似文献
43.
The most prevalent microorganisms isolated from urine specimens of dogs (385) and cats (132) with clinical signs of urinary tract infections were Escherichia coli, Proteus spp., and Staphylococcus aureus. The results of quantitative urine-culturing methods showed 48.6% of the canine and 12.1% of the feline specimens had more than 10(5) organisms per ml of urine. The bacteria isolated appear to have a greater resistance to antibacterial agents than previously reported. 相似文献
44.
45.
以来源Trametes sp.C30 的LAC3漆酶基因为研究对象,通过引物设计进行突变,在其C端和N端进行延长,分别引入6 个组氨酸标签,并异源表达于酿酒酵母Saccharomyces cerevisiae中,将获得的重组酶进行比较发现漆酶末端氨基酸序列的改变对酶学性质的影响较大。C端引入组氨酸标签的重组酶的表达量不受影响,但是在N末端引入组氨酸标签的重组酶表达量只有LAC3的一半。添加组氨酸标签的融合蛋白对ABTS和SGZ两种底物的亲和力得到增强。而在酸碱稳定性耐受方面,与LAC3相比,N末端氨基酸的改变使其在酸碱稳定性方面得到了增强,中碱性条件下仍能保持较佳活性。C端和N端可塑性的研究对于漆酶新性状的获得具有重要意义。 相似文献
46.
47.
M Tormo AM Tari TJ McDonnell F Cabanillas J Garcia-Conde G Lopez-Berestein 《Canadian Metallurgical Quarterly》1998,30(3-4):367-379
The roles of Bcl-2 protein and the protein ratio of Bcl-2/Bax in regulating cell growth in various lymphoma cell lines were examined. A dose-dependent decrease in Bcl-2 protein expression was observed in the different lymphomas incubated with lipid-incorporated bcl-2 antisense oligonucleotides (L-bcl-2). Growth inhibition was observed in a transformed follicular lymphoma (FL) cell line, which has the t(14;18) translocation and Bcl-2 protein overexpression. One of the mechanisms by which L-bcl-2 growth inhibition is mediated in these transformed FL cells might be through apoptotic induction, because the treated cells had an increased apoptotic index and showed the typical DNA fragmentation. These studies indicate that Bcl-2 protein is critical in the growth regulation of transformed FL cells. L-bcl-2 did not induce growth inhibition in lymphoma cells not expressing Bcl-2 or Bax protein. Thus, the protein ratio of Bcl-2/Bax may also be important in regulating the growth of these lymphomas. 相似文献
48.
AM Cirla N Sforza GP Roffi A Alessandrini R Stanizzi N Dorigo E Sala F Della Torre 《Canadian Metallurgical Quarterly》1996,51(5):299-305
A double-blind, placebo-controlled study was carried out to test the clinical efficacy and safety of local nasal immunotherapy (LNIT) in powder form. Twenty-two patients suffering from allergic rhinitis strictly associated with early spring symptoms, with positive skin prick tests and RAST for birch-alder, all responders to a specific nasal provocation test (NPT), received randomly active or placebo treatment for 4 months. Immunotherapy consisted of administration of a set of capsules containing progressively increasing amounts of birch (Betula pendula) and speckled alder (Alnus incana) allergens in powder form with controlled granulometry. The active (birch-alder) and placebo (lactose) group completed the treatment according to a similar schedule. During the pollen season (March-April), the patients who took the active treatment reported less sneezing and rhinorrhea than the placebo group, on the basis of a symptoms score, and the differences were statistically significant; the need for drugs (terfenadine) was also significantly reduced. These findings agreed well with the results of specific NPT after the treatment; only patients in the active group had a higher threshold dose of nasal specific reactivity to birch-alder allergens than in tests before the LNIT. 相似文献
49.
Dyslipidaemia may be treated with a number of safe and effective pharmacological agents that target specific lipid disorders through a variety of mechanisms. The bile-acid sequestrants--cholestyramine and colestipol--primarily decrease LDL cholesterol by binding bile acids, thereby decreasing intrahepatic cholesterol, and by increasing the activity of LDL receptors. Nicotinic acid lowers LDL cholesterol and triglyceride by decreasing VLDL synthesis and by decreasing free fatty acid mobilization from peripheral adipocytes. The HMG-CoA reductase inhibitors--fluvastatin, lovastatin, pravastatin and simvastatin--lower LDL cholesterol by partially inhibiting HMG-CoA reductase (the rate-limiting enzyme of cholesterol biosynthesis) and by increasing the activity of LDL receptors. The fibric-acid derivatives--bezafibrate, ciprofibrate, clofibrate, fenofibrate and gemfibrozil--primarily decrease triglyceride by increasing lipoprotein lipase activity and by decreasing the release of free fatty acids from peripheral adipose tissue. Probucol decreases LDL cholesterol by increasing non-receptor-mediated LDL clearance; as an anti-oxidant, probucol also decreases LDL oxidation; oxidized LDL which is thought to lead to atherogenesis. Although these agents have been proven safe in clinical trials, like any drug, they carry the risk for adverse effects. The bile-acid sequestrants may cause constipation, reflux oesophagitis, and dyspepsia, and may bind coadministered medications such as digitalis glycosides, beta blockers, warfarin, and exogenous thyroid hormone. Nicotinic acid use is commonly associated with flushing and pruritus and may also cause non-specific gastrointestinal complaints, hepatotoxicity (hepatic necrosis, hepatitis, or elevated liver enzymes), gout, myolysis, decreased glucose tolerance and increased fasting glucose levels, and ophthalmological complications including decreased visual acuity, toxic amblyopia, and cystic maculopathy. The HMG-CoA reductase inhibitors may produce liver enzyme elevations, creatine kinase elevations and rhabdomyolysis. The combination of a reductase inhibitor and a fibrate increases the risk for rhabdomyolysis. Possible adverse effects of the fibric-acid derivatives include abdominal discomfort, nausea, flatulence, increased lithogenicity of bile, liver enzyme elevations and creatine kinase elevations. Probucol may increase the QTc interval and may cause non-specific gastrointestinal complaints. 相似文献
50.
Competence as communication skills and as skilled practice of asepsis were studied by observing four nurses while interacting with patients and performing intravenous procedures. Nurses were observed using sterile equipment for methods of intravenous therapy. Asepsis is performed frequently, but through misunderstanding in the learning of asepsis or improper model learning the nurses may establish incorrect routines. When performing procedures, unexpected factors can distract both the expert and the inexperienced, resulting in a failure to apply basic aseptic techniques. The nurses showed an interest in the patient by listening and giving responses. Nurses may control interactions with the patient by using undesirable communication skills which include incomplete sentences, incomplete explanations and closed questions. Asked to evaluate their own behavior, the nurses did not estimate whether or not the appropriate skills were applied in observed situations. To improve the quality of nursing care performance it is recommended to further develop and apply skill training programs. 相似文献