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11.
Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome aberrations including two cases of 47,XXY, four cases involving a 45,X cell line and three autosomal trisomies. Molecular analysis of the parental origin of the deleted or supernumerary chromosome was performed by using polymorphic microsatellite markers. Six cases involving a sex chromosome abnormality were found to be of paternal origin while the two trisomic cases that could be analysed were of maternal origin. Two cases involved the same infertile couple who had two consecutive ICSI pregnancies terminated because of a chromosome abnormality. The replaced embryos in both cases originated from a single batch of ICSI fertilized oocytes of which part was used to initiate the first pregnancy and part was cryopreserved and used to initiate the second pregnancy.   相似文献   
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Objectives: A prospective study comparing the efficiacy and side-effects of oral sulindac with intravenous indomethacin in clinically stable preterm infants (<1750 g) requiring non-invasive closure of haemodynamically significant patent ductus arteriosus.
Methodology: As maturity and birthweight are the two major determinants of ductal closure, infants were matched as closely as possible for these parameters. An eligible patient was first assigned to the sulindac group and a subsequent patient with similar gestational age (± 1 week) and birthweight (±100 g) to the previously recruited infant would automatically receive indomethacin. A total of eight infants were enrolled in each group.
Results: The ductus arteriosus was successfully closed in all eight infants receiving indomethacin, and in seven of eight infants receiving sulindac. No significant differences were found with regards to the ductal size between the two groups at diagnosis or on each of the consecutive days of treatment ( P >0.25). More renal adverse effects were encountered in the indomethacin group. Significant differences in changes from baseline value for urine output, plasma sodium, urea and creatinine concentrations were noted at 24, 48 and 72 h after commencement of treatment between the two groups ( P <0.05). All the parameters returned to normal or pre-treatment levels 48 h after stopping therapy. Unexpectedly, severe gastrointestinal complications were encountered in the sulindac group.
Conclusions: Sulindac is capable of promoting ductal constriction in clinically stable preterm infants without compromising the renal function. The spectrum of gastrointestinal complications observed in sulindac treated infants were similar to those described for indomethacin. The use of sulindac for ductal closure in the preterm infant should remain experimental.  相似文献   
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This study compares different immunosuppressive regimens in the treatment of the lupus-like nephritis of NZB/W mice. Groups of 5-month-old female NZB/W mice were given azathioprine, cyclophosphamide and methylprednisolone in all one-, two- and three-drug regimens, each drug in the relatively low dose of 1.5 mg/kg/day. Treatment for 3 months with one or two drugs resulted in modest suppression of NZB/W disease. Mice receiving all three drugs had significantly less proteinuria, lower titers of anti-DNA antibody and less severe, histologically evident renal involvement than mice treated with one or two drugs. Survival at 1 year was 10% for untreated controls, 44% for one-drug-treated, 37% for two-drug-treated and 86% for the three-drug-treated mice. The survival for the three-drug regimen was significantly longer than any other group (P < 0.01). The three-drug regimen was synergistic, since mice treated with each drug at three times the dose had significantly more proteinuria after 3 months of treatment and lowered 1 year survival (33%). The beneficial effects of triple-drug therapy were attained without increased toxicity. This study represents the first controlled evaluation of single versus combination therapy in a model of autoimmune disease. Based on these results, a controlled evaluation of triple-drug therapy in human systemic lupus erythematosus appears warranted.  相似文献   
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The dextrorotatory enantiomer of fluoxetine was slightly more potent than the levorotatory enantiomer in antagonizing the depletion of brain serotonin by p-chloroamphetamine in rats. The time course of the depletion of brain serotonin at times out to 24 hr after the injection of p-chloroamphetamine was determined with or without simultaneous administration of one of the fluoxetine enantiomers. The dextrorotatory enantiomer prevented the depletion of brain serotonin at any time after p-chloroamphetamine. The levorotatory enantiomer prevented the initial depletion of brain serotonin at 2 and 4 hr, but by 8 hr brain serotonin concentration was decreased and by 24 hr the depletion of serotonin was almost as great as in rats treated with p-chloroamphetamine alone. The elevation of serum corticosterone that occurred acutely after injection of a low dose of p-chloroamphetamine was significantly antagonized by both enantiomers of fluoxetine, the dextrorotatory enantiomer being slightly more potent. In contrast, the lowering of DOPAC (3,4-dihydroxyphenylacetic acid) concentration in rat brain by p-chloroamphetamine was not antagonized by either enantiomer of fluoxetine, indicating this effect is not secondary to serotonin release by p-chloroamphetamine. The results are consistent with other evidence that both enantiomers of fluoxetine are potent inhibitors of serotonin uptake, the dextrorotatory enantiomer being longer-acting than the levorotatory enantiomer in rats.  相似文献   
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A 46-year-old man ingested approximately 50 ml of a plastic resin catalyst He developed persistent gastrointestinal bleeding, renal and hepatic failure, pneumonitis, and septicemia, and died four weeks later. Autopsy revealed chronic esophagitis and gastritis with massive intraluminal gastrointestinal hemorrhage. This case emphasizes the potential danger of ingestion of such substances.  相似文献   
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Comparison of cleansing methods in preparation for colonic surgery   总被引:3,自引:5,他引:3  
Golytely, an oral gut lavage solution, was compared with a standard bowel cleansing preparation in patients undergoing elective colonic surgery. Sixty patients were randomly assigned to either a one-day preparation with Golytely and bisacodyl or a standard method using a three-day clear liquid diet, cathartics, and enemas. Colon cleansing was better with Golytely (100 percent optimal cleansing vs. 64 percent, P less than 0.05). Patients receiving Golytely had less weight loss and found this preparation more tolerable. Quantitative stool cultures before and after preparation and intraoperatively were not significantly different between the two preparations. In this surgical bowel preparation study, Golytely and Bisacodyl were found to be safe, rapid, and effective. The preparation was well tolerated by patients and has become our preferred method of colonic cleansing.  相似文献   
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In congestive heart failure (CHF), the neurohormonal mechanisms that cause renal vasoconstriction, particularly those depending on the renin-angiotensin system, could interfere with renal vasodilating mechanisms. To elucidate this issue, we studied the kidney response to an amino acid infusion (known to cause renal vasodilation in healthy individuals) in eight patients with CHF. We found that the amino acid infusion (0.7 mL/kg/h of a 10% solution) elicited no renal hemodynamic response, in marked contrast to healthy subjects. We next hypothesized that the renin-angiotensin system (known to be activated in heart failure) has a role in the lack of response to the amino acid infusion. To test this hypothesis, we repeated the study after two 5-mg doses of enalapril, an inhibitor of the angiotensin-converting enzyme, administered 12 hours apart. After enalapril treatment, the amino acid infusion caused a 45% increase in mean renal blood flow (RBF) from 383 +/- 55 to 557 +/- 51 mL/min at the fifth hour (P < 0.05). This normalization of the renal response to the amino acid infusion occurred without changes in cardiac output or in systemic vascular resistance. Hence, the renal fraction of the cardiac output increased during the amino acid infusion. The recovery of the renal vascular response was not accompanied by an increase in glomerular filtration rate (GFR; filtration fraction decreased), suggesting a predominant efferent arteriole dilatation. Our study shows that, in heart failure, the kidney loses its ability to increase RBF in response to an amino acid load. This lack of renal vascular response can be restored by inhibiting the renin-angiotensin system and is unrelated to changes in systemic hemodynamics.  相似文献   
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