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971.
V Mijatovic P Kenemans JC Netelenbos ER Peters-Muller GJ van Kamp GA Voetberg PH van de Weijer MJ van der Mooren 《Canadian Metallurgical Quarterly》1997,82(11):3543-3547
Lipoprotein(a) [Lp(a)] is an independent risk factor for atherosclerosis. Serum Lp(a) concentrations increase after menopause, and postmenopausal estrogen replacement appears to decrease Lp(a) levels. In a randomized, double blind study, we examined the effects of 6-month treatment with daily 17 beta-estradiol (E2; 2 mg, orally) continuously combined with one of four dosages [2.5 mg (n = 41), 5 mg (n = 38), 10 mg (n = 38), and 15 mg (n = 20)] of dydrogesterone on fasting serum Lp(a) concentrations in 137 healthy postmenopausal women. At baseline, no significant differences were noted among the four treatment groups. During the study period of 6 months the median serum Lp(a) concentration decreased significantly from 128 mg/L (range, 5-1660) to 110 mg/L (range, 1-1530) in the total population, corresponding to a reduction of 13% (P < 0.001). The percent changes in serum Lp(a) correlated positively with the percent changes in serum E2 at 3 as well as 6 months of therapy (r = 0.38; P < 0.001 and r = 0.35; P < 0.001, respectively). A dose response of dydrogesterone on serum Lp(a) was not found. In addition, serum lipids and (apo)lipoproteins improved significantly in all four treatment groups. In conclusion, oral E2 continuously combined with dydrogesterone has beneficial effects on the lipid and lipoprotein profile and is effective in lowering Lp(a) concentrations in postmenopausal women. 相似文献
972.
YT van Duynhoven MJ van de Laar WA Schop PH Rothbarth WI van der Meijden AM van Loon MJ Sprenger 《Canadian Metallurgical Quarterly》1997,73(6):488-492
OBJECTIVE: To determine the prevalence and risk factors for hepatitis B virus (HBV) infections among individuals attending an STD clinic in a low endemic region. STUDY DESIGN: A total of 1228 women and 1648 men attending the STD clinic at the University Hospital Rotterdam, Netherlands, were examined for HBV infection by determination of hepatitis B surface antigen (HBsAg) and antibodies to hepatitis B core antigen (anti-HBc). Demographic characteristics, information on sexual behaviour, and intravenous drug use were recorded. RESULTS: The seroprevalence of HBsAg was 1.4% in women and 2.1% in men (0% in homosexual men). The seroprevalence of anti-HBc was 13% in women and 20% in men (36% in homosexual men). Native country, intravenous drug use, a history of STD, and the number of partners in the past half year (inversely) were independent risk factors for HBsAg positivity in women and heterosexual men. For anti-HBc independent associations were observed for native country, age, intravenous drug use, commercial sex, number of lifetime partners, homosexual contacts, orogenital contact (inverse), and a history of STD. CONCLUSION: The HBV prevalence in the STD clinic attendants was high, exceeding the national estimate, and indicates that the STD clinic population may be considered a high risk group. Our data confirmed an increased risk for HBV infections among established risk groups. Therefore, these risk groups should be routinely screened to identify HBV cases for counselling and contact tracing. 相似文献
973.
974.
K Chlichlia ME Peter M Rocha C Scaffidi M Bucur PH Krammer V Schirrmacher V Umansky 《Canadian Metallurgical Quarterly》1998,91(11):4311-4320
Nitric oxide (NO), an important effector molecule involved in immune regulation and host defense, was shown to induce apoptosis in lymphoma cells. In the present report the NO donor glycerol trinitrate was found to induce apoptosis in Jurkat cells that are sensitive to CD95-mediated kill. In contrast, a CD95-resistant Jurkat subclone showed substantial protection from apoptosis after exposure to NO. NO induced mRNA expression of CD95 (APO-1/Fas) and TRAIL/APO-2 ligands. Moreover, NO triggered apoptosis in freshly isolated human leukemic lymphocytes which were also sensitive to anti-CD95 treatment. The ability of NO to induce apoptosis was completely blocked by a broad-spectrum ICE (interleukin-1beta converting enzyme)-protease/caspase inhibitor and correlated with FLICE/caspase-8 activation. This activation was abrogated in some neoplastic lymphoid cells but not in others by the inhibitor of protein synthesis cycloheximide. Our results were confirmed using an in vitro experimental model of coculture of human lymphoid target cells with activated bovine endothelial cells generating NO as effectors. Furthermore, the inhibition of endogenous NO production with the inducible NO synthase inhibitor NG-monomethyl-L-arginine caused a complete abrogation of the apoptotic effect. Our data provide evidence that NO-induced apoptosis in human neoplastic lymphoid cells strictly requires activation of caspases, in particular FLICE, the most CD95 receptor-proximal caspase. Depending on the cell line tested this activation required or was independent of the CD95 receptor/ligand system. 相似文献
975.
RP Gale RE Park RW Dubois GP Herzig WG Hocking MM Horowitz A Keating S Kempin CA Linker CA Schiffer PH Wiernik DJ Weisdorf KR Rai 《Canadian Metallurgical Quarterly》1998,22(11):973-981
BACKGROUND: There is controversy over whether high-dose therapy and a bone marrow transplant is better than conventional-dose chemotherapy in adults with acute lymphoblastic leukemia (ALL) in first remission. This decision may depend on which type of donor is available: an HLA-identical sibling, an alternative donor transplant (HLA-matched related or unrelated people other than HLA-identical siblings), or autotransplant. OBJECTIVE: To determine the appropriate use of high-dose therapy and bone marrow transplants in ALL in first remission. Develop a treatment algorithm. PANELISTS: Nine leukemia experts from diverse geographic sites and practice settings. EVIDENCE: Boolean MEDLINE searches of acute lymphoblastic leukemia and chemotherapy and/or transplants. CONSENSUS PROCESS: We used a modified Delphi-panel group judgment process. Age, white blood cell (WBC) count, cytogenetics and immune type were permuted to define 48 clinical settings. Each panelist rated appropriateness of high-dose therapy and a transplant versus conventional-dose chemotherapy on a 9-point ordinal scale (1, most inappropriate; 9, most appropriate) considering three types of donors: (1) HLA-identical siblings; (2) alternative donors; and (3) autotransplants. An appropriateness index was developed based on median rating and amount of disagreement. Relationship of appropriateness indices to the permuted clinical variables was considered by analysis of variance and recursive partitioning. Preference between donor types was analyzed by comparing mean appropriateness indices of comparable settings and a treatment algorithm was developed. CONCLUSIONS: In people with an HLA-identical sibling donor, transplants were rated appropriate in those with unfavorable cytogenetics and uncertain in all other settings. An HLA-identical sibling donor was always preferred to an alternative donor or autotransplant. In people without an HLA-identical sibling but with an alternative donor, this type of transplant was rated appropriate in those with unfavorable cytogenetics. However, an autotransplant was preferred over an alternative donor transplant in all other settings where a transplant was rated uncertain. In people without an HLA-identical sibling or alternative donor, autotransplants were rated uncertain in all settings except in those with not unfavorable cytogenetics, WBC < 100 x 10(9) l(-1) and T- or pre-B-cell type where they were rated inappropriate. 相似文献
976.
We have constructed a HAPPY map of the apicomplexan parasite Cryptosporidium parvum. We have placed 204 markers on the 10.4-Mb genome, giving an average marker spacing of approximately 50 kb, with an effective resolution of approximately 40 kb. HAPPY mapping (an in vitro linkage technique based on screening approximately haploid amounts of DNA by the polymerase chain reaction) is fast and accurate and is not subject to the distortions inherent in cloning, meiotic recombination, or hybrid cell formation. In addition, little genomic DNA is needed as a substrate, and the AT content of the genome is largely immaterial, making it an ideal method for mapping otherwise intractable parasite genomes. The map, covering all eight chromosomes, consists of 10 linkage groups, each of which has been chromosomally assigned. We have verified the accuracy of the map by several methods, including the construction of a >140-kb PAC contig on chromosome VI. Less than 1% of our markers detect non-rDNA duplicated sequences. 相似文献
977.
978.
979.
The aim of this study was to develop a reliable and simple method for hepatitis C virus (HCV)-PCR using standard, automated laboratory equipment. HCV-RNA was extracted from serum and amplified in a single PCR with an internal standard. The PCR product was detected using fluoroimmunoassay. Quantification was based on external and internal standards. Linearity was observed over a wide range (10-10(7) geq). Mean inter and intra serial coefficients of variation were 35% and 23%, respectively. The limit of quantification was 1000 geq/ml based on intra and inter serial variations, while levels of 110 geq/ml were always detectable. Lower concentrations were intermittently positive. The ability to separate HCV-signals in healthy and infected persons was good, based on the distribution of HCV-signals from 353 random blood donors and 191 patient samples. To illustrate the applicability of the test, HCV-RNA quantification was performed in 11 patients during treatment with interferon alpha-2b. Ten of 11 patients showed a decline in HCV-RNA within the first few weeks of treatment. After four weeks most patients were still HCV-RNA positive but below the limit of quantification. The present method for quantification of HCV-RNA was shown to have sensitivity at the level of nested PCR techniques. Until now HCV-PCR has been complicated, time-consuming and costly, and therefore not suitable for routine diagnostics. The PCR method described here is easy to perform, fast and cost-effective. 相似文献
980.
GA Elder VL Friedrich P Bosco C Kang A Gourov PH Tu VM Lee RA Lazzarini 《Canadian Metallurgical Quarterly》1998,141(3):727-739
Neurofilaments (NFs) are prominent components of large myelinated axons and probably the most abundant of neuronal intermediate filament proteins. Here we show that mice with a null mutation in the mid-sized NF (NF-M) subunit have dramatically decreased levels of light NF (NF-L) and increased levels of heavy NF (NF-H). The calibers of both large and small diameter axons in the central and peripheral nervous systems are diminished. Axons of mutant animals contain fewer neurofilaments and increased numbers of microtubules. Yet the mice lack any overt behavioral phenotype or gross structural defects in the nervous system. These studies suggest that the NF-M subunit is a major regulator of the level of NF-L and that its presence is required to achieve maximal axonal diameter in all size classes of myelinated axons. 相似文献