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排序方式: 共有4747条查询结果,搜索用时 15 毫秒
71.
Dr. S. O. Ukabam MD MRCP Dr. B. T. Cooper MD MRCP 《Digestive diseases and sciences》1984,29(9):809-816
Mannitol (molecular weight 182), lactulose (342), and polyethylene glycol 400 (range 242–550) absorption was studied in 25 controls, 22 untreated celiacs, and 13 treated celiacs. Untreated celiacs absorbed less mannitol and more lactulose than controls. Absorption of higher as well as lower molecular-weight polyethylene glycols was reduced in untreated celiac disease. Absorption returned towards normal on treatment. Polyethylene glycol and lactulose absorption was enhanced by administering them in a hypertonic solution. Polyethylene glycol 400 but not lactulose or mannitol was lipid solublein vitro. It was concluded that the mucosa in untreated celiac disease was more leaky than normal. Polyethylene glycol 400 absorption data suggested that its absorption may largely be determined by its lipid solubility and was decreased in celiac disease because of the reduced surface area of the small intestine. Polyethylene glycol 400 cannot be recommended as a suitable marker for permeability studies of the small intestine. 相似文献
72.
Michael Phillips MRCP Preston Hensley PhD Richard A. Baiter MD Stanley L. Cohan MD 《Alcoholism, clinical and experimental research》1984,8(3):293-296
An improved method is described for the collection of breath for the subsequent assay of acetaldehyde and other volatile components. Breath is collected in a Pyrex gas-collecting tube sealed at both ends with Teflon taps. Prior to collection or assay of the samples, this tube is heated to 72 degrees C; breath is sampled for assay by piercing a rubber septum on a sideport with the needle of a similarly heated gas-tight syringe, and injected into a gas chromatograph (GC). The advantages of this system are: (1) Avoidance of the artefacts encountered in the assay of acetaldehyde in the blood; (2) suitability for sample collection at a site remote from the GC laboratory; (3) avoidance of sample loss by leakage, contamination, or partitioning into water condensed from breath; and (4) compatibility with a "nondedicated" GC lacking any special gas-collecting circuitry. A typical study of a normal human volunteer is described, demonstrating the rise and fall of the concentration of acetaldehyde and ethanol in the breath following the ingestion of an oral dose of ethanol. 相似文献
73.
Aorto-iliac aneurysms may entrap the ureters in perianeurysmal fibrosis, causing medial ureteral deviation and/or obstruction. The latter has been described only in male patients; a further 5 cases due to iliac and 3 to aortic aneurysm are reported. The radiologic picture resembles retroperitoneal fibrosis; the correct diagnosis may be suggested when ureteral tethering or narrowing lies near arterial calcification. Sonography is usually the most appropriate investigation to confirm the diagnosis. When sonography shows an aortic aneurysm, the kidneys should be scanned to rule out hydronephrosis. Similarly, films of the kidneys should be obtained when an abdominal aneurysm is demonstrated by aortography. 相似文献
74.
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76.
JC VANCE DC CHANT DI TUDEHOPE PH GRAY AJ HAYES 《Journal of paediatrics and child health》1997,33(6):504-508
Objectives: To describe the physical growth patterns of infants born to narcotic dependent mothers (INDM) over a 12 months period and, if possible, to relate the growth to drug taking patterns during pregnancy.
Methodology: The growth of a cohort of 43 INDM was measured during the first 12 months of life. Weight and length measurements were compared with percentile charts and converted to Z scores. Questionnaire data about drug taking practices, demographic variables and the neonatal period (including withdrawal scores) were obtained.
Results: Twenty-four (55.8%) of INDM had evidence of neonatal drug withdrawal requiring treatment with phenobarbitone. At birth, Z scores for weight and length indicated relative intrauterine growth retardation. By 12 months, there had been some catch up growth, but Z scores for weight and length were still below zero. Persistent weight retardation at 12 months was correlated with methadone dosage during pregnancy, but not the need for phenobarbitone therapy.
Conclusions: The growth patterns of INDM in the first 12 months of life indicated that at birth there was evidence of intrauterine growth retardation, but by 12 months the growth was little different from the rest of the community. There appears to be some influence of narcotic agents taken while pregnant on subsequent growth of INDM. 相似文献
Methodology: The growth of a cohort of 43 INDM was measured during the first 12 months of life. Weight and length measurements were compared with percentile charts and converted to Z scores. Questionnaire data about drug taking practices, demographic variables and the neonatal period (including withdrawal scores) were obtained.
Results: Twenty-four (55.8%) of INDM had evidence of neonatal drug withdrawal requiring treatment with phenobarbitone. At birth, Z scores for weight and length indicated relative intrauterine growth retardation. By 12 months, there had been some catch up growth, but Z scores for weight and length were still below zero. Persistent weight retardation at 12 months was correlated with methadone dosage during pregnancy, but not the need for phenobarbitone therapy.
Conclusions: The growth patterns of INDM in the first 12 months of life indicated that at birth there was evidence of intrauterine growth retardation, but by 12 months the growth was little different from the rest of the community. There appears to be some influence of narcotic agents taken while pregnant on subsequent growth of INDM. 相似文献
77.
Gonzales AJ; Christensen JG; Preston RJ; Goldsworthy TL; Tlsty TD; Fox TR 《Carcinogenesis》1998,19(7):1173-1183
78.
Identification of differentially expressed genes in aflatoxin B1- treated cultured primary rat hepatocytes and Fischer 344 rats 总被引:4,自引:1,他引:4
Harris AJ; Shaddock JG; Manjanatha MG; Lisenbey JA; Casciano DA 《Carcinogenesis》1998,19(8):1451-1458
Aflatoxin B1 (AFB1), a mutagen and hepatocarcinogen in rats and humans, is
a contaminant of the human food supply, particularly in parts of Africa and
Asia. AFB1-induced changes in gene expression may play a part in the
development of the toxic, immunosuppressive and carcinogenic properties of
this fungal metabolite. An understanding of the-role of AFB1 in modulating
gene regulation should provide insight regarding mechanisms of AFB1-induced
carcinogenesis. We used three PCR- based subtractive techniques to identify
AFB1-responsive genes in cultured primary rat hepatocyte RNA: differential
display PCR (DD-PCR), representational difference analysis (RDA) and
suppression subtractive hybridization (SSH). Each of the three techniques
identified AFB1- responsive genes, although no individual cDNA was isolated
by more than one technique. Nine cDNAs isolated using DD-PCR, RDA or SSH
were found to represent eight genes that are differentially expressed as a
result of AFB1 exposure. Genes whose mRNA levels were increased in cultured
primary rat hepatocytes after AFB1 treatment were corticosteroid binding
globulin (CBG), cytochrome P450 4F1 (CYP4F1), alpha-2 microglobulin,
C4b-binding protein (C4BP), serum amyloid A-2 and glutathione S-transferase
Yb2 (GST). Transferrin and a small CYP3A-like cDNA had reduced mRNA levels
after AFB1 exposure. Full-length CYP3A mRNA levels were increased. When
liver RNA from AFB1-treated male F344 rats was evaluated for transferrin,
CBG, GST, CYP3A and CYP4F1 expression, a decrease in transferrin mRNA and
an increase in CBG, GST, CYP3A and CYP4F1 mRNA levels was also seen.
Analysis of the potential function of these genes in maintaining cellular
homeostasis suggests that their differential expression could contribute to
the toxicity associated with AFB1 exposure.
相似文献
79.
80.
A novel method to measure mitral valve area in patients with rheumatic mitral stenosis using three‐dimensional transesophageal echocardiography: Feasibility and validation
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