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11.
An in vitro Study on the Effect of Momordica charantia on Glucose Uptake and Glucose Metabolism in Rats 总被引:1,自引:0,他引:1
The effect of extracts of MOMORDICA CHARANTIA L. fruits on glucose metabolism and glucose uptake was investigated. The fruit of momordica, at all ripening stages, was found to contain two inhibitory compounds: one against hexokinase activity and the other against glucose uptake by rat intestinal fragments. Both inhibitions exhibit competitive profiles VERSUS glucose. The inhibitory factors are extractable in hot water, hot alcohol and hot acetone. A partial purification procedure by TLC for both inhibitors is described. 相似文献
12.
Embryo transfer (ET) is the last stage of extracorporal fertilization during which the embryo is placed in the uterine cavity with a medium-filled catheter 2–3 days after in vitro fertilization. While fertilization in the laboratory occurs at very high rates (>:90%), the overall success of the procedure (i.e., take home baby) is still very low (<25%) and assumed to be mainly due to implantation failure. A computational model was developed to simulate ET within the uterine cavity by a fluid-filled catheter inserted into a two-dimensional channel with oscillating walls. The results showed that the speed at which the embryos are injected from the catheter dominates the procedure and controls the velocity of their transport within the uterine cavity. ET at excessively high injection speeds may lead to ectopic pregnancies, while uterine peristalsis affects transverse dispersion only during injection at low injection speeds. The presence of the catheter within the uterus does not affect flow patterns downstream of its tip. The potential risks to implantation failure due to mechanical factors involved in the ET processes are discussed. © 2003 Biomedical Engineering Society.
PAC2003: 8719-j, 8710+e 相似文献
13.
Pirie PL Stone EJ Assaf AR Flora JA Maschewsky-Schneider U 《Health education research》1994,9(1):23-36
Community-based programs are being widely adopted in the struggle to prevent chronic disease. Program evaluation of community-based programs involves a particular set of problems stemming from the variety of activities being undertaken simultaneously, the multiple intermediate goals of the programs and the rapidity with which the programs evolve. An analysis of the experience of four large community-based cardiovascular disease research and demonstration studies (Stanford Five-City Project, Minnesota Heart Health Program, Pawtucket Heart Health Program and the German Cardiovascular Prevention Project) provides valuable models, methodologies and strategies for planning and conducting evaluations of public health programs or community studies. By comparing and combining their experiences, the four programs have identified eight categories of evaluation for community studies, including formative evaluation, quality assurance, assessment of delivered dose, assessment of received dose, component program impact, intermediate outcomes, community impact and cost analysis. This paper presents information on the strategies by which each of the four programs addressed these evaluation categories. 相似文献
14.
Oral Sessions
Oral session 42—Motor neuron disease (3) 相似文献15.
The aim of this study was to investigate the effects of oxidant stress on endothelium-dependent and endothelium-independent arterial relaxation. For this, oxidant stress was generated by preincubation of rat aortic rings (RARs) in either 25 mM glucose (mimicking hyperglycemic stress) or 0.5 mM pyrogallol (a superoxide generator) and the effects of the superoxide dismutase (SOD)-mimetic compound 4-hydroxy-2,2,6,6-tetramethylpiperidinyloxy free radical (TEMPOL) on the vasorelaxant and cGMP-producing effects of acetylcholine (ACh) and glyceryl trinitrate (GTN) in control RARs and RARs exposed to oxidant stress were examined. Pyrogallol, and to a lesser extent high glucose concentration, enhanced the contractile response of RARs to phenylephrine and markedly inhibited the vasorelaxant response to ACh. Although they existed, the inhibitory effects of high glucose and pyrogallol on the vasorelaxant response to GTN were less profound, especially with pyrogallol. Moreover, both pyrogallol and high glucose concentration inhibited the basal and the ACh-induced vascular cyclic guanosine monophosphate (cGMP) production. Treatment with TEMPOL (1-5 mM) slightly increased the ACh and GTN-induced cGMP levels in control RARs but had a significant effect in high glucose and pyrogallol-pretreated RARs. Additionally, concomitant treatment of RARs with TEMPOL (5 mM) abolished the difference in the relaxation response between control RARs and RARs exposed to either pyrogallol or high glucose concentration. These results further support the theory that reactive oxygen species (ROS), especially superoxide, play a key role in mediation of endothelial dysfunction accompanying diabetes, probably through their effects on the ability of the endothelium to synthesize, release or respond to endogenous nitric oxide (NO) or NO donated by nitrovasodilators. 相似文献
16.
Studies on bone marrow extracts from ten animal species have revealed the presence of thermostable antigens. Similar antigens were found in other organs as shown by immunodiffusion and cross-reactivity was demonstrated between the thermostable proteins from horse and dog and between cow and sheep proteins. Using an immunoenzymatic reaction with glucose oxidase as the marker, the thermostable antigens were localized in the blood and bone marrow polymorphonuclear leukocytes and the myeloid cell line. 相似文献
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18.
Andrianasolo EH Haramaty L Vardi A White E Lutz R Falkowski P 《Journal of natural products》2008,71(7):1197-1201
Two monogalactosyl diacylglycerols, 1 and 2, were isolated from the marine diatom Phaeodactylum tricornutum, using the patented ApopScreen cell-based screen for apoptosis-inducing, potential anticancer compounds. The molecular structures of the galactolipids were determined using a combination of NMR, mass spectrometry, and chemical degradation. The bioactivities were confirmed using a specific apoptosis induction assay based on genetically engineered mammalian cell lines with differential, defined capacities for apoptosis. The galactolipids induce apoptosis in micromolar concentrations. This is the first report of apoptosis induction by galactolipids. 相似文献
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20.
In an extensive ethnobotanical survey (130 informants) of the medicinal plants of Israel, 16 species were found to be used for hypoglycaemic treatments. The list includes Achillea fragrantissima (Forssk.) Sch.-Bip, Ammi visnaga (L.) Lam, Atriplex halimus L., Capparis spinosa L., Ceratonia siliqua L., Cleome droserifolia (Forssk.) Del., Eryngium creticum Lam., Inula viscosa (L.) Ait., Matricaria aurea (Loefl.) Sch.-Bip, Origanum syriaca L., Paronychia argentea Lam, Prosopis farcta (Banks et Sol.) Macbride, Salvia fruticosa Mill., Sarcopoterium spinosum (L.) Sp., and Teucrium polium L.; eight of them (marked with an asterisk) are first recorded here as used for this purpose. 相似文献