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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   
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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   
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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   
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The neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was injected intraperitoneally in mice and caused an acute inhibition (of over 60%) of gastrointestinal motility, which was measured by the transit of charcoal. This inhibition was not related to conversion of MPTP to MPP+. Administration of the -adrenergic blocker propranolol significantly reduced, but did not completely block, the effect of MPTP. The dopaminergic blocker haloperidol also partly reversed the effects of MPTP. When these blockers were administered together, the action of MPTP was fully blocked. The results indicate that the toxin acted by releasing catecholamines (presumably norepinephrine and dopamine), thereby inhibiting motility.Supported by a grant from the Joint Research Fund of the Hebrew University and Hadassah.  相似文献   
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Oral Sessions

Oral session 42—Motor neuron disease (3)  相似文献   
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To establish whether endometrial blood flow and thickness can predict the success rate of in-vitro fertilization, 156 cycles were evaluated. The parameters were: endometrial colour and power Doppler pulsatility index (PI), resistance index (RI), systolic/diastolic ratio (S/D) and endometrial thickness. Each patient was studied: on the day of ovum retrievalpickup, and on the day of embryo transfer. Non-endometrial parameters studied were: age, oestrestrogen and progesterone concentrations, number of oocytes, and number of embryos. Pregnancy was achieved in 31 cycles. On the day of ovum retrieval, patients who conceived had PI, RI, and S/D values of 0.997, 0.563, and 2.403, respectively. Patients who did not conceive had values of 0.994, 0.584, and 2.477 respectively. The power Doppler technique provided similar results. On the day of embryo transfer, pregnant patients had PI, RI and S/D values of 1.096, 0.590 and, 2.597 respectively, while in the non-pregnant patients the values were 1.104, 0.603 and, 2.723 respectively. Power Doppler showed similar numbers. The differences between pregnant and non-pregnant patients were not statistically significant in any of the parameters. Endometrial thickness and blood flow does not seem to correlate with pregnancy rate in IVF.  相似文献   
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While conflict-induced forced migration is a global phenomenon, the situation in Colombia, South America, is distinctive. Colombia has ranked either first or second in the number of internally displaced persons for 10 years, a consequence of decades of armed conflict compounded by high prevalence of drug trafficking. The displacement trajectory for displaced persons in Colombia proceeds through a sequence of stages: (1) pre-expulsion threats and vulnerability, (2) expulsion, (3) migration, (4) initial adaptation to relocation, (5) protracted resettlement (the end point for most forced migrants), and, rarely, (6) return to the community of origin. Trauma signature analysis, an evidence-based method that elucidates the physical and psychological consequences associated with exposures to harm and loss during disasters and complex emergencies, was used to identify the psychological risk factors and potentially traumatic events experienced by conflict-displaced persons in Colombia, stratified across the phases of displacement. Trauma and loss are experienced differentially throughout the pathway of displacement.  相似文献   
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