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21.
Meir P  Yaniv Z 《Planta medica》1985,51(1):12-16
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   
22.
International Urology and Nephrology - To quantify the occurrence of stent failure and the dynamic behavior of urine flow in ureter-stent systems, including the relative flow in the ureter and...  相似文献   
23.
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   
24.
Understanding the process of behavior change interventions is critical to achieving campaign effectiveness and successful program replication. The present article presents a community education monitoring system (CEMS) using data from the Stanford Five-City Project (FCP), the Minnesota Heart Health Program (MHHP) and the Pawtucket Heart Health Program (PHHP). CEMS records the number and type of intervention activities, outcome objectives, targets of change (individual, organizational or environmental), channel(s) of dissemination and proportion of programs funded by the community. These data illustrate (1) the application of theory for each project, (2) data-based program administration, (3) feedback for revising programs and (4) type of reach or 'dose' information obtained from intervention monitoring. Process evaluations such as CEMS provide critical links between field realities and evaluation outcomes. This type of evaluation develops standards for measuring program reach and allows comparisons with other programs. CEMS also illustrates how programs enact theory. Validation studies are critical to the continued successful use of CEMS. The first step, however, is to develop a uniform way of describing complex multichannel behavior change programs. CEMS in a refined form should prove invaluable to health promotion program planners whether in research or service settings.  相似文献   
25.
Assaf AA 《Strabismus》1997,5(2):59-66
A total of 101 patients (total group) with primary large angle esotropia who had primary bimedial rectus recession (BMR) of 6.5 mm or more were reviewed in a retrospective study. The average pre-operative size of the deviation was 63.5 prism diopters (PD) for near and 58.2 PD for distance. Of these, 26 patients (group I) attended for one post-operative visit only. The remaining 75 patients (group II) were followed for an average period of 17.7 months. Among group II patients there was an average shift in the post-operative deviation towards divergence consisting of-6.4 PD for near and-5.5 PD for distance. The alignment (deviation of 10 PD or below) rate in the first postoperative visit was 31.7%; undercorrection was 60.4% and overcorrection was 7.9%. At the end of the period of follow-up the above rates were 40%, 42.7%, and 17.3% respectively without further surgery. This increase in the overcorrection rate was solely derived from the initially aligned patients. Amblyopia and/or poor fixation were found to be of significance in the production of overcorrection. There was no direct relationship between the age of surgery, duration of follow-up or the degree of the BMR and the rate of correction. Among group II patients, post-operative ocular movements analysis revealed limitation of adduction of-0.5 to-0.75 (out of scale 0 to-4.00) in 22.7% (17/75) and-1.00 to-1.50 in 6.7% (5/75). None had more than-1.5 limitation of adduction. Large BMR is an acceptable surgical modality for the management of large angle esotropia. It has approximately 50% alignment rate. Slight undercorrection is recommended especially in the presence of significant amblyopia and/or poor fixation. No significant limitation of adduction was encountered.  相似文献   
26.
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   
27.

Oral Sessions

Oral session 42—Motor neuron disease (3)  相似文献   
28.
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   
29.
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   
30.
During this study, 134 samples have been examined for the detection of the viruses associated with neonatal calf diarrhea. The presence of Nebraska viruses (rotavirus and coronavirus) has been demonstrated by using the electron microscope and the fluorescent antibody techniques while the presence of other viruses has been detected by the observation of a cytopathic effect on monolayer cells of calf testis. The Nebraska viruses have been demonstrated in 107 (80%) out of 134 field case specimens. An association of rotaviruses and coronaviruses was found in 58 cases (54%) whilst the coronaviruses and the rotavirus were found singly in 34 cases (53%) and in 15 cases (14%) respectively. Four bovine virus diarrhea viruses, two infectious bovine rhinotracheitis viruses and two enteroviruses have also been isolated in the preceding 107 Nebraska positive specimens. For the detection of the Nebraska viruses, the fluorescent antibody techniques were more sensitive than the electron microscopy. However, those two techniques must be used simultaneously for a better detection of a greatest possible number of cases.  相似文献   
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