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7-甲氧基-4′-羟基-3′-二乙胺甲基异黄酮(MHDF)对大鼠血流动力学和主动脉的作用 总被引:2,自引:0,他引:2
本实验观察了MHDF对整体大鼠血流动力学和离体大鼠胸主动脉的作用。结果表明iv MHDF(3~12.8 mg/kg)能降低大鼠左心室±dp/dtmax,Vmax,Vpm和LVSP,延长T-dp/dtmax,减慢心率。MHDF还能舒张大鼠胸主动脉,ED50为6.5×10-6mol/L;非竞争拮抗NA和CaCl2致主脉收缩,pD2′为3.11±0.21和3.73±0.07;抑制高K+致主动脉收缩,IC50为1.76×10-5mol/L。提示MHDF对血管的作用与α受体阻断剂不同,而可能与钙拮抗有关。 相似文献
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Nonsteroidal anti-inflammatory drug use and increased risk for peptic ulcer disease in elderly persons 总被引:25,自引:0,他引:25
M R Griffin J M Piper J R Daugherty M Snowden W A Ray 《Annals of internal medicine》1991,114(4):257-263
OBJECTIVE: To evaluate the relative risk for peptic ulcer disease that is associated with the use of nonaspirin nonsteroidal anti-inflammatory drugs. DESIGN: Nested case-control study. SETTING: Tennessee Medicaid program. PARTICIPANTS: Medicaid enrollees 65 years of age or older were included in the study. The 1415 case patients had been hospitalized for confirmed peptic ulcer disease at some point from 1984 through 1986. The 7063 control persons represented a stratified random sample of other Medicaid enrollees. MEASUREMENTS AND MAIN RESULTS: The estimated relative risk for the development of peptic ulcer disease among current users of nonaspirin nonsteroidal anti-inflammatory drugs, compared with that among nonusers, was 4.1 (95% CI, 3.5 to 4.7). For current users, the risk increased with increasing dose, from a relative risk of 2.8 (CI, 1.8 to 4.3) for the lowest to a relative risk of 8.0 (CI, 4.4 to 14.8) for the highest dose category. The risk was greatest in the first month of use (relative risk, 7.2; CI, 4.9 to 10.5). If the association is fully causal, 29% of peptic ulcers in the study sample resulted from the use of these drugs, and the excess risk associated with such use was 17.4 hospitalizations for ulcer disease per 1000 person-years of exposure. CONCLUSIONS: These data support other findings indicating that a clinically significant risk for serious ulcer disease is associated with the use of nonaspirin nonsteroidal anti-inflammatory drugs. The data show that this risk increases with dose and recency of use and that use of these drugs may be responsible for a large proportion of peptic ulcer disease among elderly persons. 相似文献
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Antigen detection immunoassay using dipsticks and colloidal dyes 总被引:5,自引:0,他引:5
A dipstick colloidal dye immunoassay (DIA) for multiple antigen detection is described. The test combines the concepts of double antibody (Ab) sandwich ELISA, dot blotting, and colloidal particle-linked Abs to produce a dipstick test for multiple antigen (Ag) detection. Dipsticks prepared from Ab coated nitrocellulose membrane mounted on acetate strips served as the assay capture matrix. Abs absorbed to colored dye particles from a family of commercially available textile dyes (Dye/Ab reagent) served as Ag detecting reagents. DIA and enzyme labelled dot blot assays showed similar Ag detection limits down to a sensitivity of 10 ng/ml. In a pilot study, an assay designed to detect species-specific IgG for use in mosquito bloodmeal identification demonstrated the feasibility of the technique. Experiments comparing bloodmeal analysis of mosquitoes using DIA and ELISA methods showed 100% agreement. This DIA method provides an inexpensive, simple, robust test for multiple Ag detection without instrumentation suitable for a wide variety of field applications. 相似文献
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Summary In two elderly patients with frontal lobe dementia and in two others with progressive aphasia an inverse relationship between the severity of protein deposition and the principal pathology of these disorders was noted. Deposition of protein occurred only in areas of cortex where functional (viable) neurones were still present and was absent where neuronal decimation had taken place. Such findings suggest that the presence of functional neurones is necessary for protein deposition to occur and, therefore, that neurones may be the source of the amyloid protein that is deposited within brain parenchyma not only in these disorders but also in other conditions, particularly Alzheimer's disease.Supported by a grant from the North Western Regional Health Authority (DJ) and a B.Sc Intercalated Studentship from the MRC (PWS) 相似文献
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Encephalitozoon cuniculi and E. hellem are often recognized as the agents of human microsporidiosis, but less than optimal therapy is available for treatment. The identification of enzymes critical to the parasitic life cycle is an important step in finding targets for potential drug development. Aminopeptidase gene sequences were obtained from cDNA and gDNA from avian and human E. hellem isolates and from a rabbit E. cuniculi isolate. At the amino acid level, the aminopeptidase sequences from the E. hellem human and bird isolates share >99% identity and are nearly 70% identical with the E. cuniculi sequence. Conserved HEXXH and GAMEN motifs classify the predicted aminopeptidase in the MA clan of the M1 family. The obtained aminopeptidase gene sequences are likely homologous to the previously reported E. cuniculi glutamyl aminopeptidase. The conservation of this aminopeptidase between species and divergence from mammalian aminopeptidases indicate that this enzyme may be a valid target for drug therapy. 相似文献
9.
Proliferation of ovarian stromal cells is a common phenomenon in peri- and post-menopausal ovaries. It is generally assumed to be secondary to the rise in circulating gonadotrophins at the menopause, though the process by which it occurs is poorly understood. This study aimed to examine the effect of menopausal levels of pituitary gonadotrophins on the growth of primary cultures of ovarian stroma. A culture system was developed using primary explants of ovarian stroma on a collagen substrate. The effect of follicle stimulating hormone (FSH; 10(-5) g/l) and luteinizing hormone (LH; 10(-5) g/l) on the proliferation of cultures derived from the cortices and medullae of ten ovaries was evaluated using a dual radiothymidine labelling technique. FSH was stimulatory to cortical cultures from 9/10 ovaries and medullary cultures from 7/10 ovaries, while LH was stimulatory to cortical cultures from 6/9 ovaries and medullary cultures from 5/10 ovaries. The responsiveness of the cultures did not correlate with the degree of hyperplasia in vivo. This study demonstrates that pituitary gonadotrophins may modulate the growth of stromal cells in culture, and thus may play a role in the process whereby stromal proliferation occurs in peri- and post-menopausal ovaries. 相似文献
10.
Andrew D Chantry John A Snowden Charles Craddock Karl Peggs Claire Roddie Jenny I O Craig Kim Orchard Keiren E Towlson Rachel M Pearce David I Marks 《Biology of blood and marrow transplantation》2006,12(12):1310-1317
Relapsed acute myeloid leukemia (AML) in adults has a poor prognosis if treated with chemotherapy alone. Case series have previously supported the role of myeloablation and autologous transplantation as a potentially curative treatment. This study aimed to use the large numbers and extended follow-up data in the British Society of Blood and Marrow Transplantation (BSBMT) registry database to establish long-term outcomes and relate these to biological and procedural factors. The BSBMT registry database was used to retrospectively identify 152 adult patients (age, 16-69 years) with AML in second remission treated with autologous transplantation in 1982-2003. Cytogenetic data were available for 68% of the patients; of these, at diagnosis, 42% had good risk features, 57% had standard risk features, and 1% had poor risk features. Conditioning regimens varied; autologous rescue was provided with bone marrow (BM) (71%), peripheral blood stem cells (PBSCs) (18%), or both (11%), which were harvested during first complete remission (CR1) and/or second CR (CR2). Median follow-up was 84 months (range, 2-200 months). At 10 years, actuarial overall survival (OS) was 32%, progression-free survival (PFS) was 28%, and relapse rate (RR) was 57%. The 100-day nonrelapse mortality (NRM) was 7%, rising to 11% at 1 year and to 14% at 10 years. OS was significantly related to M3 subtype (5-year OS, 66%; P = .005), patient age at diagnosis (P = .005) and transplantation (P = .026), and length of CR1, with greatest significance if the patient was dichotomized at CR1 duration of < 8 months or > or = 8 months (P = .0001). There was no difference in OS between regimens containing total body irradiation (TBI) and chemotherapy alone (P = .7). In relation to the nature of autologous graft material, there was improved OS (P = .025) and PFS (P = .009) with the use of cells harvested entirely in CR1 compared with cells harvested in CR2 or in both CR1 and CR2. Engraftment times were significantly shortened with the use of PBSCs alone or in combination with BM compared with BM alone (P = .0001), but there was no significant long-term impact on OS, PFS, RR, or NRM. This study provides long-term follow-up data in one of the largest series of patients with standard-risk and good-risk AML in CR2 treated with autologous transplantation and supports earlier observations that long-term survival is achievable in about 1/3 of patients overall and in about 2/3 of patients with M3 with a relatively low NRM. Outcomes are better in patients with CR1 > or = 8 months by use of grafts obtained entirely in CR1 and use of PBSCs. TBI conditioning did not confer an advantage. Randomized studies against unrelated donor transplantation are warranted. 相似文献