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51.
薄层扫描法测定藤茶中二氢杨梅素的含量   总被引:11,自引:1,他引:11  
目的:建立藤茶质量控制的方法,方法:采用薄层扫描法测定藤茶中二氢杨梅素的含量。结果:藤茶中二氢杨梅素的含量38.17%-38.54%,回收率为98.5%,RSD为1.6%,结论:该法快速、简单、稳定、测定结果准确、可靠。  相似文献   
52.
Chromosomal breakpoints affecting immunoglobulin (IG) loci are recurrent in many subtypes of B-cell lymphomas. However, despite the predominant B-cell origin of the Hodgkin and Reed-Sternberg (HRS) cells in classical Hodgkin lymphoma (cHL), the presence of chromosomal translocations in IG loci has not yet been systematically explored. Therefore, we have investigated a series of cHL for chromosomal breakpoints in the IGH (n = 230), IGL (n = 139), and IGK (n = 138) loci by interphase cytogenetics. Breakpoints in the IGH, IGL, or IGK locus were observed in the HRS cells of 26 of 149 (17%), 2 of 70, and 1 of 77 evaluable cHLs, respectively. The IG partners could be identified in eight cHLs and involved chromosomal bands 2p16 (REL), 3q27 (BCL6, two cases), 8q24.1 (MYC), 14q24.3, 16p13.1, 17q12, and 19q13.2 (BCL3/RELB). In 65 of 85 (76%) cHLs evaluable for an IGH triple-color probe, the HRS cells showed evidence for a (partial) deletion of the IGH constant region, suggesting the presence of class switch recombination (CSR). Furthermore, analyses with this probe in cases with IGH breakpoints indicated that at least part of them seem to be derived from CSR defects. Our results show that chromosomal breakpoints affecting the IG loci are recurrent in cHL.  相似文献   
53.
目的:探讨氯喹对烟雾吸入伤大鼠肺细胞膜ATP酶活性及丙二醛含量的影响,方法:80只Wistar大鼠随机分成正常对照组,烟雾吸入伤1,3,6,12和24h组以及氯喹治疗6h和12h组,分别于各时相点活杀动物,取肺制备膜制剂,用生化比色法测定膜上Na^+,K^+-ATP酶Mg^2+-ATP酶和Ca^2+-ATP酶活性,用比色法测定膜上丙醛含量,并用定磷法测定膜总磷脂含量,结果:烟雾吸入伤后,肺细胞膜3  相似文献   
54.

Background and purpose:

Gram-negative bacteria contain ligands for Toll-like receptor (TLR) 4 and nucleotide oligomerization domain (NOD) 1 receptors. Lipopolysaccharide (LPS) activates TLR4, while peptidoglycan products activate NOD1. Activation of NOD1 by the specific agonist FK565 results in a profound vascular dysfunction and experimental shock in vivo.

Experimental approach:

Here, we have analysed a number of pharmacological inhibitors to characterize the role of key signalling pathways in the induction of NOS2 following TLR4 or NOD1 activation.

Key results:

Vascular smooth muscle (VSM) cells expressed NOD1 mRNA and protein, and, after challenge with Escherichia coli or FK565, NOS2 protein and activity were induced. Macrophages had negligible levels of NOD1 and were unaffected by FK565, but responded to E. coli and LPS by releasing increased NO and expression of NOS2 protein. Classic pharmacological inhibitors for NF-κB (SC-514) and mitogen-activated protein kinase (SB203580, PD98059) signalling pathways inhibited responses in both cell types regardless of agonist. While TLR4-mediated responses in macrophages were specifically inhibited by the pan-caspase inhibitor z-VAD-fmk and the PKC inhibitor Gö6976, NOD1-mediated responses in VSM cells were inhibited by the Rip2 inhibitor PP2.

Conclusions and implications:

Our findings suggest a selective role for NOD1 in VSM cells, and highlight NOD1 as a potential novel therapeutic target for the treatment of vascular inflammation.  相似文献   
55.
We studied the influence of hyperglycemia lasting 1, 4, 6 and 8 months on the reactivity and ultrastructure of the aorta in Wistar rats. Moreover, the effect of the pyridoindole antioxidant stobadine ((-)-cis-2,8-dimethyl-2,3,4,4a,5,9b-hexahydro-1H-pyrido[4,3-b]indole) on the changes induced by the 8-month hyperglycemia were studied. Hyperglycemia was induced by streptozotocin (STZ, 55 mg/kg i.v.). In the functional study, responses to KCl, acetylcholine (ACh), noradrenaline (NA) and hydrogen peroxide were evaluated under isometric conditions. The first changes in aortic reactivity started after 1 month of hyperglycemia and were exhibited by significantly increased NA-induced contractions. Relaxant responses to acetylcholine were decreased, although not significantly. Prolongation of hyperglycemia to 4, 6 and 8 months did not cause any additional significant changes in responsiveness to NA. Decreased ACh-induced relaxation and increased contractile responses to H2O2 were observed in month 4. The functional responses were not substantially deteriorated by prolongation of hyperglycemia to 6 and 8 months. Ultrastructural examination of the diabetic aorta showed disturbances in normal tissue organization. An 8-month supplementation of stobadine in diabetic rats resulted in the protection of aortic function as well as its ultrastructure. These results suggest that abnormalities occurring in the aorta of diabetic rats might result from the damaging effects of oxygen free radicals.  相似文献   
56.
本文初步研究了诺氟沙星缓释片的处方组成。并对不同处方进行了体外溶出试验,实验结果表明:本品的体外释药可维持12h以上且体外溶出符合一级动力学过程。  相似文献   
57.
58.
Clinical study of the efficiency of Poetam (affinity-purified antibodies to recombinant human erythropoietin) in the treatment of anemia in patients with pubertal uterine hemorrhages proved that combined therapy with Poetam and iron preparation normalized erythron parameters, structural and metabolic status of erythrocytes, and ferrokinetic parameters of the peripheral blood sooner than monotherapy with Poetam or sorbifer. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 142, No. 7, pp. 70–74, July, 2006  相似文献   
59.
Any nuclear war would be horrific and our main aim should be universal abolition of nuclear weapons. Civil defence, with its medical attributes, could certainly increase the survival rate should a disaster occur. The effect of the explosion of a nuclear warhead is outlined, together with what could be done to reduce casualties. Nuclear winter is discussed and it is suggested that the results of computerization of doubtful surmises have been treated too much as proven facts. The possibility of its occurrence should not deter emergency planning. Civil defence can save lives, and the fact that medicine as we know it would cease to exist in an all‐out nuclear war does not excuse us from doing what we can to increase the survival rate, if the worst should happen. Action should therefore be taken now to plan decentralization of resources and to instruct the public in protection, first aid and self‐sufficiency.  相似文献   
60.
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