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71.
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The pharmacokinetics and metabolism of 4-demethoxydaunorubicin (idarubicin, IDA) were studied in 21 patients with advanced cancer after i.v. (12 mg/m2) and oral (30-35 mg/m2) treatment according to a balanced crossover design. Patients were divided into four groups: subjects who showed normal liver and kidney function (group N), those who presented with normal kidney function and liver metastases (group L), those with kidney dysfunction (creatinine clearance, less than or equal to 60 l/h; group R), and those with both liver and kidney dysfunction (group LR). Five patients showed variations in liver or kidney function after the first treatment and were considered to be nonevaluable for the crossover study but evaluable for the liver/kidney function study; some of them appeared in different groups for the i.v. as opposed to p.o. treatments. After i.v. administration, IDA plasma levels followed a triphasic decay pattern. The main metabolite observed in all patients was the 13C-reduced compound (IDAol), which attained plasma levels 2-12 times higher than those of the parent compound. IDA pharmacokinetics was not dependent on the presence of liver metastases but was related to the integrity of kidney function. Analysis of variance indicated a significant correlation between IDA plasma clearance and creatinine clearance; it was also found that IDA plasma clearance was lower in patients whose creatinine clearance was less than 60 ml/min [group N, 122.8 +/- 44.0 l/h; group L, 104.4 +/- 27.7 l/h (P = 0.58) vs group R, 83.4 +/- 18.3 l/h (P = 0.037)]. The IDAol terminal half-life and mean residence time (MRT) were significantly increased in patients with impaired kidney function [MRT: group N, 63.6 +/- 10.8 h; group L, 69.9 +/- 10.2 h (P = 0.27) vs group R, 83.2 +/- 10.9 h (P = 0.025) and t1/2 gamma: group N, 41.3 +/- 10.1 h; group L, 47.0 +/- 7.4 h (P = 0.31) vs group R, 55.8 +/- 8.2 h (P = 0.025)]. After oral treatment, drug absorption occurred during in the first 2-4 h after IDA administration; a biphasic decay pattern was observed thereafter. The main metabolite observed in all patients was again IDAol. The AUC of IDAol was greater after oral administration than after i.v. treatment in proportion to the AUC of IDA (i.v.: AUC-IDAol/AUC-IDA, 2.4-18.9; p.o.: AUC-IDAol/AUC-IDA, 4.1-21.4). Following oral dosing, a substantial amount of 4-demethoxydaunomycinone (AG1) was found in 11/21 patients.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
73.
A 46-year-old man developed a symmetrical parkinsonian syndrome 7 weeks after large right temporal intracerebral haemorrhage resulting from a ruptured arteriovenous malformation. His signs included bradykinesia, rigidity, start hesitation, and poor postural reflexes, without a resting tremor. He also had signs of a Parinaud's syndrome. Computed tomography and magnetic resonance imaging of the brain demonstrated changes in the right temporal lobe associated with the haemorrhage but no abnormality of the basal ganglia or midbrain. Levodopa therapy produced a dramatic improvement within a few days of commencement. We postulate that the parkinsonism resulted from midbrain compression secondary to transtentorial herniation. Although parkinsonism is a rare complication of lobar intracerebral haemorrhage, it is important to recognise as it may be potentially treatable.  相似文献   
74.
We have examined the patterns of expression of the major intermediate filament (IF) protein mRNAs during development of the hamster brain. Quantitative northern blotting was used to examine changes in the levels of mRNAs for the low, middle and high molecular weight neurofilament proteins (NF-L, NF-M, NF-H) as well as peripherin, vimentin and glial fibrillary acidic protein (GFAP). Total RNA was isolated from hamster brains at embryonic (E) days 12 and 14 and postnatal (P) days 1, 3, 5, 7, 9, 11, 13, 15, 20, 28 and 60-90 (adult), and probed with specific IF cDNAs. Northern blotting revealed that NF-L and NF-M mRNAs were present at very low levels in embryonic brain and that significant expression of these genes only occurred postnatally when the levels increased dramatically until P28 and then declined again in the adult. Increases in NF-H mRNA levels were somewhat delayed relative to those of NF-L and NF-M. NF-H mRNA was not seen at embryonic stages and was expressed at very low levels prior to P9; after that time the levels increased rapidly until P28 and then declined in the adult. Two of the type III IF genes, peripherin and vimentin, followed a pattern of expression opposite that of the NF genes. Both peripherin and vimentin mRNAs were present in embryonic brain and were expressed at higher levels during early postnatal stages than at later times. The magnitude and rate of reduction in vimentin gene expression in the postnatal interval was much greater than that of peripherin. GFAP mRNA levels were extremely low prior to P9 after which a robust increase occurred, followed by a decline in the adult. We discuss the implication of the dramatic changes in IF isotype expression in brain to the pathways of both neuronal and glial development in vivo.  相似文献   
75.
Prospective study of phobic anxiety and risk of Parkinson's disease.   总被引:3,自引:0,他引:3  
Anxiety disorders are common in Parkinson's disease (PD). However, the risk of PD among people with anxiety has not been examined in a prospective cohort study. We examined this relation prospectively within the Health Professionals Follow-Up Study, a cohort of US male health professionals. In 1988, anxiety was assessed using the Crown-Crisp phobic anxiety index in 35,815 men without PD, stroke, or cancer at baseline. There were 189 incident cases of PD during 12 years of follow-up. After adjusting for age, smoking, and caffeine intake, the relative risk of PD among men with the highest level of anxiety (Crown-Crisp index scores of 4 and above) was 1.5 (95% CI = 1.0-2.1; P-trend = 0.01) compared to men with the lowest level of anxiety. This positive association persisted after excluding cases of PD with onset in the first 2 years of follow-up. Use of anxiolytic medication was also associated with an elevated risk of PD (RR= 1.6; 95% CI = 0.9-3.1), but adjusting for this potential confounder did not materially affect the association between anxiety and risk of PD. Our results suggest that anxiety is a risk factor for PD. Whether this association is causal or the result of shared underlying biology remains a question.  相似文献   
76.
A 66-year-old man with atrial fibrillation was referred soon after developing left lower limb and abdominal pain with rectal bleeding. An immediate flush aortogram showed embolic occlusion of the left distal superficial femoral artery and superior mesenteric artery (SMA), 3 cm from its ostium. Recombinant tissue plasminogen activitor (rtPA) 40 mg was selectively in stilled in the SMA in two boluses. Abdominal symptoms resolved within 48 h, and complete recanalization of the SMA was shown on angiography. Exploratory laparotomy after 72 h showed a normal small bowel and right colon, and was completed by femoropopliteal embolectomy. Six months later, the patient remained asymptomatic.  相似文献   
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Summary. In this paper, registry data on infants born in Sweden between 1983 and 1986 are reviewed to describe the epidemiological characteristics of infants with single umbilical artery (SUA). During this period 372 066 births were registered with information on the number of umbilical vessels. Our data set contains 1782 SUA infants. The incidence at birth was: in multiple births 0.8%, in infants with chromosome anomalies 6.1% and in singletons without a known chromosome anomaly 0.46%. Incidence was higher in girls than in boys. There were no consistent seasonal variations in the date of presumed conception. Low birthweight (<2500 g) and preterm birth (<37 weeks) were seen more frequently in SUA singleton infants than in infants with three vessels. At any given gestation, SUA infants had a lower mean birthweight than infants with three vessels. The risk of having a SUA infant was increased in women over 40 years, and slightly increased at or above parity of three.  相似文献   
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