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21.
ED Schneiderman SM Willis CJ Kowalski TR Ten have 《Canadian Metallurgical Quarterly》1993,32(1):35-43
Sixty-five patients initially seropositive for IgM anti-phenolic glycolipid-I (PGL-I) antibodies were tested for antibody levels to PGL-I, lipoarabinomannan (LAM), and the 35-kDa protein of Mycobacterium leprae at regular intervals for up to 30 months following the commencement of multidrug therapy (MDT). There was a steady decline in IgM anti-PGL-I and anti-35-kDa antibody levels to a mean of 17% and 14%, respectively, of the starting level at 24 months. The development of type 1 and type 2 reactions or the presence of drug-resistant organisms in a small number of patients had no significant influence on the changes in antibody level. The rate of decline was similar in different disease categories, but a higher proportion of lepromatous patients remained seropositive at the end of 2 years of treatment than borderline tuberculoid patients. By contrast, the mean IgG anti-LAM antibody levels remained stable or increased. Again the occurrence of type 1 or type 2 reactions had no significant effect on antibody level over 2 years. Falls in the IgM anti-PGL-I antibody levels mirrored the falls in the bacterial index in individual patients and provide an additional parameter for monitoring the response to chemotherapy. 相似文献
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23.
Cytochromes P450 2B metabolize a variety of compounds and have provided an excellent framework for identifying determinants of substrate specificity. Among the rat 2B enzymes, a puzzling difference has emerged between the reported substrate specificity of purified hepatic 2B2 and that of certain 2B1 mutants containing 2B1 --> 2B2 substitutions. To address these discrepancies, we have characterized two 2B2 variants. A cDNA clone designated 2B2FF was obtained from phenobarbital-induced Lewis rats and, like some previously isolated variants, was found to contain phenylalanine at positions 58 and 114. A second 2B2 clone was generated by restoring Leu and Ile, respectively, at these positions. These enzymes were expressed in Escherichia coli and analyzed with androstenedione, testosterone, progesterone, ethoxycoumarin, benzyloxyresorufin, and pentoxyresorufin. The expressed 2B2 variants metabolized most substrates at rates that were 1-9% of those of 2B1. When steroid regio- and stereospecificity was examined, the metabolite profiles of expressed 2B2 and 2B2FF conflicted with the 16beta- and 16alpha-hydroxylation observed for purified hepatic 2B2 from Sprague-Dawley rats. These and other results suggested that the purified hepatic 2B2 contained a small percent of the 2B1 enzyme. Masses of tryptic peptides were consistent with identity between purified hepatic 2B2 and 2B2FF. On the basis of a three-dimensional homology model and the construction and analysis of 2B2 mutants, residues 114, 363, 367, and 478 were identified as determinants of substrate specificity. In addition, 2B1 and the expressed 2B2 variants showed differential susceptibility to the mechanism-based inactivators chloramphenicol and N-(2-p-nitrophenethyl)chlorofluoroacetamide. 相似文献
24.
This paper focus on some characteristics of the qualitative methodology. Some of these methods are explored such as: participatory research, phenomenology, grounded theory and ethnography critical theory Perspectives of their utilization in nursing research are examined. 相似文献
25.
SM Breedlove 《Canadian Metallurgical Quarterly》1997,17(6):687-697
Electrically-assisted transdermal delivery (EATDD) is the facilitated transport of compounds across the skin using an electromotive force. It has been extensively explored as a potential means for delivering peptides and other hydrophilic, acid-labile or orally unstable products of biotechnology. The predominant mechanism for delivery is iontophoresis, although electroosmosis and electroporation have also been investigated. The focus of this review is to put these different mechanisms in perspective and relate them to the drug and skin model system being investigated. 相似文献
26.
Cervical disc disease includes acute herniation and chronic disc degeneration with secondary changes in the associated bone. The latter may lead to the spectrum of cervical spondylitic stenosis, which is considered to be multilevel and may be more of a bony disease. Clinically, cervical disc disorders can be divided into several disorders. The disorder of true cervical radiculopathy is associated with lateral compression of the nerve root. When this condition is due to a lateral soft disc herniation or lateral bony stenosis, the posterior cervical laminoforaminotomy is commonly used. It is a procedure that works extremely well in the vast majority of patients and there is no risk of spinal instability; therefore, no fusion is required. The details of operative care have been described. In patients who have persistent radicular problems after a failed anterior cervical interspace procedure, the posterior cervical laminoforaminotomy with posterior wiring and fusion is a simple and effective operative option. 相似文献
27.
RG Wilde JT Billheimer SJ Germain EA Hausner PC Meunier DA Munzer JK Stoltenborg PJ Gillies DL Burcham SM Huang JD Klaczkiewicz SS Ko RR Wexler 《Canadian Metallurgical Quarterly》1996,4(9):1493-1513
Acyl-CoA:cholesterol acyltransferase (ACAT) is the enzyme largely responsible for intracellular cholesterol esterification. A systemic inhibitor of ACAT is believed to be able to slow or even reverse the atherosclerotic process. Towards that goal, a series of cyclic sulfides, derived from the hetero-Diels-Alder reaction of thioaldehydes with 1,3-dienes, and bearing carboxamide substituents, were prepared and evaluated for in vitro (in several tissues and species) and ex vivo ACAT inhibition. Minor changes in subsequent structure were found to have a significant effect in optimization of the biological activity of this series of compounds. 相似文献
28.
29.
Infantile osteopetrosis is a lethal disorder resulting from a severe defect in the ability of osteoclasts to resorb bone. The only therapy shown to be capable of providing lasting benefit is allogeneic hematopoietic stem cell transplantation (HCT). We report the outcome of 10 patients with infantile malignant osteopetrosis treated with HCT from an HLA A, B, DRB1 matched (n=6) or A or B locus mismatched (n=4) family member or unrelated donor at the University of Minnesota between 1978 and 1997. Eight of 10 patients achieved primary engraftment; secondary graft failure was seen in two patients. Five of 10 patients survive; three with full or partial donor chimerism and two with autologous hematological recovery. Transient or partial donor chimerism can be sufficient to correct the hematological manifestations of osteopetrosis. We recommend early referral for consideration of HCT with a related or unrelated donor as neurosensory manifestations of osteopetrosis are generally not reversible. Donor engraftment may be easier to achieve early in the course of the disease. 相似文献
30.
WS Ahn J Yoo SW Huh CK Kim JM Lee SE Namkoong SM Bae IP Lee 《Canadian Metallurgical Quarterly》2003,12(5):383-390
We investigated clinical efficacy of green tea extracts (polyphenon E; poly E and (-)-epigallocatechin-3-gallate [EGCG]) delivered in a form of ointment or capsule in patients with human papilloma virus (HPV) infected cervical lesions. Fifty-one patients with cervical lesions (chronic cervicitis, mild dysplasia, moderate dysplasia and severe dysplasia) were divided into four groups, as compared with 39 untreated patients as a control. Poly E ointment was applied locally to 27 patients twice a week. For oral delivery, a 200 mg of poly E or EGCG capsule was taken orally every day for eight to 12 weeks. In the study, 20 out of 27 patients (74%) under poly E ointment therapy showed a response. Six out of eight patients under poly E ointment plus poly E capsule therapy (75%) showed a response, and three out of six patients (50%) under poly E capsule therapy showed a response. Six out of 10 patients (60%) under EGCG capsule therapy showed a response. Overall, a 69% response rate (35/51) was noted for treatment with green tea extracts, as compared with a 10% response rate (4/39) in untreated controls (P<0.05). Thus, the data collected here demonstrated that green tea extracts in a form of ointment and capsule are effective for treating cervical lesions, suggesting that green tea extracts can be a potential therapy regimen for patients with HPV infected cervical lesions. 相似文献