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An 84-year-old woman experienced an acute anterior wall myocardial infarction complicated by cardiogenic shock. Coronary angiography demonstrated a subtotal occlusion of the proximal left anterior descending artery. Conventional percutaneous transluminal coronary angioplasty, including a 15-minute perfusion balloon dilatation resulted in a persistent intraluminal filling defect with high grade stenosis and ongoing ischemia and hypotension. Coronary splinting was performed, using an autoperfusion balloon to achieve a 6-hour dilatation of the vessel in conjunction with balloon aortic counterpulsation. The patient remained hemodynamically stable during this lengthy dilatation without ECG evidence of ischemia. Angiography postdilatation demonstrated a minor residual stenosis with no evidence of intraluminal thrombus. The patient was discharged 8 days later without congestive heart failure. Follow-up at 3 months demonstrated normal left ventricular function with no evidence of anterior wall infarction or ischemia by thallium imaging . (J Interven Cardiol 1996;9:65–67) 相似文献
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Mature (60-65 day old) male Sprague-Dawley rats received a single intraperitoneal injection of ethylene dimethane sulphonate (EDS; 100 mg/kg) and were subsequently killed at various times from day 2 to day 40 post-treatment. Testes were removed from these animals and age-matched controls and utilized either for light and electron microscopical analyses or for in-vitro assessment of Leydig cell function. Interstitial cells were prepared by collagenase digestion and used to measure 125I-labelled human chorionic gonadotrophin (hCG) binding capacity and androgen production in the presence or absence of hCG or dibutyryl cyclic AMP (dbcAMP). At day 2 after EDS treatment, 125I-labelled hCG binding capacity was reduced to 10% of control values, while the production of testosterone and 5 alpha-androstane-3 alpha, 17 beta-diol (adiol) were non-detectable. Histological observations confirmed the lack of identifiable Leydig cells at day 2-16 after EDS treatment. Between days 24 and 40 post-treatment, Leydig cell regeneration occurred, as indicated by a rise in 125I-labelled hCG binding capacity, increased androgen production and the presence of histologically identifiable Leydig cells. A pattern of adiol production similar to that seen in the immature rat during Leydig cell development was observed with peak synthesis occurring at day 30 post-treatment. Adiol production fell to barely detectable levels by day 36 and remained low at day 40. It is concluded that the steroidogenic pattern of regenerating Leydig cells in the EDS-treated animal is similar to that of developing Leydig cells in the immature animal. 相似文献
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ABSTRACT. This study was designed to investigate the family environment and the temperament of children with Down's syndrome (DS). Parents of 40 children with DS completed the Family Environmental Scale (FES). They also were asked to fill out the Temperament Assessment Battery for Children (TABC) for both the child with DS and the nearest same-sex sibling. A similar questionnaire of the TABC (teacher form) was sent to the children's teachers. The results of these investigations revealed that there were high scores in categories cohesion, expressiveness, achievement, moral/religious emphasis, organization and control on the FES, indicating that family members in the study cohort are relationship oriented, provide support for one another, emphasize ethical values and are able to express their feelings. Comparing TABC results between children with DS with their siblings, significant differences were observed in such categories as adaptability, approach/withdrawal and persistence . Control children were scoring higher in the adaptability and persistence categories, whereas children with DS achieved significantly higher scores than the control children in the approachiwithdrataal category. 相似文献
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Developmental Toxicity Evaluation of Ethylene Glycol by Gavage in New Zealand White Rabbits 总被引:1,自引:1,他引:0
TYL ROCHELLE W.; PRICE CATHERINE J.; MARR MELISSA C.; MYERS CHRISTINA B.; SEELY JOHN C.; HEINDEL JERROLD J.; SCHWETZ BERNARD A. 《Toxicological sciences》1993,20(4):402-412
Artificially inseminated New Zealand white (NZW) rabbits wereadministered ethylene glycol (EG) by gavage on Gestational Days(GD) 6 through 19 at doses of 0, 100, 500, 1000, or 2000 mg/kg/day,with 2324 inseminated animals per group. Clinical signswere recorded and water consumption was measured daily; doeswere weighed on GD 0, 619, 25, and 30. At necropsy (GD30), maternal liver, kidney, and gravid uterine weights wererecorded. Histopathologic examination was performed on kidneysfrom 10 does/dose and for all unscheduled deaths. Ovarian corporalutea were counted and uterine implantation sites (total sites,resorptions, dead and live fetuses) were recorded. All livefetuses were weighed, sexed, and examined for external, visceral,and skeletal malformations and variations. EG resulted in profoundmaternal toxicity at 2000 mg/kg/day (42% mortality; three earlydeliveries and one spontaneous abortion) associated with renalpathology and unaccompanied by any other indicators of maternaltoxicity. Renal lesions at 2000 mg/kg/day involved the corticalrenal tubules and included intraluminal oxalate crystals, epithelialnecrosis, and tubular dilatation and degeneration. No dose-relatedmaternal toxicity occurred at 1001000 mg/kg/day. Therewas no indication of developmental toxicity at any dose tested,including no effects on pre- or postimplantation loss, numberof fetuses, fetal body weight, or sex ratio (% male fetuses)per litter, and no evidence of teratogenicity. The "no observableadverse effect level" (NOAEL) for maternal toxicity was therefore1000 mg/kg/day and the NOAEL for developmental toxicity wasat least 2000 mg/kg/day in this study. The sensitivity of NZWrabbits relative to that of SpragueDawley rats and Swissmice for maternal and developmental toxicity from gavage administrationof EG during organogenesis can be determined for maternal toxicity:rabbits>mice>rats, and for developmental toxicity, mice>>rats >> rabbits. 相似文献
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Developmental Phase Specificity and Dose-Response Effects of 2-Methoxyethanol in Rats 总被引:1,自引:1,他引:0
Methoxyethanol (ME) produces embryotoxic effects in rodents,rabbits, and nonhuman primates. Mechanistic evaluations of MEdysmorphogenesis have focused mainly on developmental insultsand chemical disposition in the mouse. These assessments inmice were based on developmental phase specificity (DPS) anddose response relationship (DRR) of ME. DPS and DRR indicatedtreatments for selectively inducing defects to study ME dispositionand expressed dysmorphogenesis. This study was conducted toestablish DPS and DRR of ME in the rat. DPS was determined byinjecting 500 mg ME/kg (6.6 mmol/kg) into the tail vein on GestationalDay (gd; sperm-positive day = gd 0) 10, 11, 12, 13, 14, or 15(n=6 dams/gd; saline controls on gd 12). On gd 20, embryolethalityincidence was 100% after gd 10 dosing; at gd 11 through 15,it was 50, 32, 15, 2, and 5%, respectively (control, 2%). Incidencesof external defects in live fetuses exposed on gd 1115were 97, 98, 100, 44, and 0% and those of viscera were 100,62, 44, 10, and 0%, respectively. The predominant anomaliesobserved were ectrodactyly and renal agenesis. DRR was determinedon gd 13, when live embryos/litter and external malformations(ectro and syndactyly, micromelia) were maximal. Dams (n=8/dosegroup) were injected intravenously with 0, 100, 250, 350, or500 mg ME/kg. On gd 20, fetal defect rates were 0, 0, 82.5,83.0, and 100% at these concentrations, respectively. Basedon these studies, appropriate ME doses, times of maternal exposure,and critical phases of development in the rat model are availablefor reproducing selective defects to investigate biochemicaland pharmacokinetic determinants underlying their expression. 相似文献
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