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991.
R. Bello C. Borges J. V. Esplugues J. Esplugues M. J. Lopez De Medrano-Villar E. Primo Yúfera 《Phytotherapy research : PTR》1995,9(2):128-134
The present study analyses the pharmacological activity in in vitro and in vivo models of different extracts obtained from Araujia sericifera. The hexane extract of fruits lacked toxicity, but exhibited an analgesic effect in models of chemical and thermal stimulation. Such an extract was the only one which exhibited antiinflammatory actions. The intrinsic effect on arterial blood pressure was biphasic: at low doses it significantly increased blood pressure, whereas at high doses it exerted the opposite effect. On isolated organs it produced a marked decrease in the maximum effect of histamine and acetylcholine. The dichloromethanol extract of fruits decreased arterial pressure and the maximum effect of histamine. The methanol extract of fruits slightly depressed the CNS. An analgesic effect was noted following chemical stimulation; the maximum effect of serotonin was significantly decreased. The dichloromethanol extract of seeds markedly decreased arterial pressure and the maximum effect of acetylcholine and serotonin. The methanol extract of seeds exerted an analgesic effect after chemical stimulation and modified the maximum effect of noradrenaline and serotonin. 相似文献
992.
J. Losada R. Sarria J. F. Fernandez Val M. A. Lopez Ariztegui 《Journal of surgical oncology》1995,59(1):14-17
DNA nuclear content and PCNA index (proportion of PCNA reactive cells) have been studied by flow cytometry in eight pancreatic lesions producing hyperinsulinemic hypoglycemia to assess DNA ploidy and tumoral growth fraction. Adult nesidioblastosis had a diploid DNA index, two adenomas were near diploid, and four of the adenomas and the carcinoma were aneuploid. The median value of PCNA index (6.056% ± 6.76) was significantly correlated (p <0.05) with the mean tumor diameter (2.43 cm ± 1.96). Tumors with a PCNA index <6.056% showed a diameter less than the mean tumoral diameter and a benign clinical course. Tumors with PCNA index <6.056% generally displayed a diameter bigger than the mean tumoral diameter, being associated with lymph node metastases in one case. The authors conclude that nuclear DNA and PCNA index cytometric studies are useful parameters to assess the biological behaviour of pancreatic lesions producing hyperinsulinemic hypoglycemia. 相似文献
993.
Plasmodium falciparum AMA-1 erythrocyte binding peptides implicate AMA-1 as erythrocyte binding protein 总被引:1,自引:0,他引:1
Urquiza M Suarez JE Cardenas C Lopez R Puentes A Chavez F Calvo JC Patarroyo ME 《Vaccine》2000,19(4-5):508-513
The role of AMA-1 during merozoite invasion has not yet been determined. However, reported experimental evidence suggests that this protein can be used, in particular as erythrocyte-binding protein, since, Fab fragments against this protein are able to block merozoite invasion. Using a previously described methodology, eight peptides with high binding activity to human erythrocyte, scattered along the different domains and having around 130 nM affinity constants, were identified in the Plasmodium falciparum AMA-1 protein. Their binding activity was sialic acid independent. Some of these peptides showed homology with the erythrocyte binding domains of one of the apical organelle protein family, MAEBL, identified in rodent malarial parasites. One of these peptides shares amino acid sequence with a previously reported B-cell epitope which induces antibodies to block parasite growth. The critical residues were identified for erythrocyte binding conserved peptides 4313 (DAEVAGTQYRLPSGKCPVFG), 4321 (VVDNWEKVCPRKNLQNAKFG), 4325 (MIKSAFLPTGAFKADRYKSH) and 4337 (WGEEKRASHTTPVLMEKPYY). All conserved peptides were able to block merozoite invasion of new RBC and development, suggesting that these peptides are involved in P. falciparum invasion. 相似文献
994.
Moline J Lopez Carrillo L Torres Sanchez L Godbold J Todd A 《Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine》2000,42(11):1070-1075
A pilot study was conducted in Morelos, Mexico in March 1999 to assess the body burden of lead in 24 Mexican women of childbearing age. Lead levels were measured in whole blood and at three bone sites: two primarily trabecular (calcaneus and patella) and one primarily cortical (tibia). Demographic and reproductive characteristics of the women and potential sources of lead exposure were gathered by a direct interview. An inverse relationship was noted between months of lactation and age-adjusted calcaneus lead level (P = 0.001). No association was observed between age-adjusted patella or tibia lead level and months of lactation (P = 0.15). Blood lead levels were positively associated with the use of lead-glazed ceramics (P = 0.01). Bone and blood lead levels were observed to be 77% higher in these rural Mexican women than in urban New York City women. This pilot study provides further limited evidence for the hypothesis that lead mobilization occurs during lactation. 相似文献
995.
Plummer DJ Lopez A Azen SP LaBree L Bartsch DU Sadun AA Freeman WR 《Ophthalmology》2000,107(9):1693-1701
OBJECTIVE: To compare the effectiveness of scanning laser entoptic perimetry with static automated perimetry as a noninvasive instrument for screening for glaucomatous damage in visually asymptomatic subjects within the central 60 degrees (diameter) of vision. DESIGN: A masked cross-sectional study comparing entoptic perimetry to achromatic threshold perimetry. PARTICIPANTS: Twenty-three subjects and controls from the Sharp Rees-Stealy Hospital and the Shiley Eye Center at the University of California, San Diego. TESTING: Virtual reality-based entoptic perimetry was compared with achromatic threshold perimetry. MAIN OUTCOME MEASURES: For each testing session, we compared the presence of a disturbance in the entoptic perimetry stimulus with the presence of defects in visual function as measured by Humphrey automated visual field perimetry. RESULTS: Scanning laser entoptic perimetry reasonably estimates the overall visual field loss for moderate-to-severe scotomas as measured by the pattern deviation in standard visual field perimetry. Scanning laser entoptic perimetry has a sensitivity from 27% to 90% and a specificity from 50% to 100% for screening moderate-to-severe visual field defects caused by glaucoma within the central 60 degrees diameter of vision. CONCLUSIONS: Scanning laser entoptic perimetry may be an effective and inexpensive screening test in hospitals and community clinics for diagnosing visual field loss caused by glaucoma. 相似文献
996.
B Lefèvre A Demoulin J Testart R Frydman M Lopez R Lambotte P Franchimont 《Fertility and sterility》1986,46(2):325-327
During the periovulatory period, inhibin did not have a discriminant role in oocyte fertilizability. A possible role in the gonadotropin surge was not revealed by analysis at the time of follicular rupture. Furthermore, inhibin activity appears to be very low. But inhibin could still have an effect upon growth and atresia of the follicles of the following cycles. 相似文献
997.
A clinical trial of levonorgestrel-releasing Norplant implants used for contraception was undertaken in two cities in Colombia. Through two years in which 389 women had accumulated 594 years of use, there were no pregnancies. In a comparison group of copper intrauterine device acceptors, the one-year pregnancy rate was 1.1 per 100. Menstrual disturbances associated with progestin-only administration were the principal side-effects, and the major reason for cessation of use. Continuation among users of the implants was at the same or at a higher rate than observed among users of the intrauterine device. Advantages and disadvantages of alternate sites for implant placement are discussed. 相似文献
998.
Combined pharmacologic therapy in a rabbit model of proliferative vitreoretinopathy (PVR) 总被引:4,自引:0,他引:4
PURPOSE: This study was designed to evaluate the efficacy of a combined treatment, previously used to prevent fibrosis after glaucoma surgery, to inhibit an experimental model of proliferative vitreoretinopathy (PVR). METHODS: Two groups of albino rabbits were used. In the control group (group 1, n = 14), experimental PVR was induced using vitrectomy, retinotomies, cryotherapy and intraocular injection of platelet-rich plasma. In the experimental group (group 2, n = 15), after PVR was induced, the following treatment was administered for 4 weeks: systemic methylprednisolone, sodium diclofenac and colchicine combined with topical atropine 1%, adrenaline 10% and dexamethasone phosphate 0.1%. Follow- up consisted of fundus examination for 4 weeks. Results were classified according to Fastenberg's classification. Only retinal detachments were considered to compare the two groups. Nonparametric test was used. RESULTS: Retinal detachments were observed in 85.7% of group 1 and 33.3% of group 2 at the end of the follow-up (p<0.01). No major systemic complications were observed. CONCLUSIONS: Combined therapy seems to be useful for treating experimental PVR. 相似文献
999.
Two infants with rare manifestations of the prune belly syndrome are described. Besides the usual features, the first infant
had Down syndrome. The second infant had arthrogryposis multiplex congenita, bilateral talipes equinovarus and low set malformed
ears. 相似文献
1000.
J P Deffez P Fellus E A Cabanis A Lopez 《Revue de stomatologie et de chirurgie maxillo-faciale》1984,85(4):280-283
The works of Paul Tessier, M.D., have shown the frequent association of facial and cranial clefts. After studying eleven cases of cleft palate which could be associated to encephalic anomalies, we conclude that we cannot systematize an evaluation by CAT-scan for low and isolated cleft palates. On the other hand, as soon as an association exists with: a psychomotor deficit (even slight); neurologic symptoms; a participation of the eye or the socket, the scanner evaluation becomes necessary. 相似文献