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The effects of an indirect dopamine-agonist, d-amphetamine, and a non-selective dopamine receptor antagonist, haloperidol, were investigated in normal male volunteers using a between-subjects double-blind design in a procedural learning task, thought mainly to involve unconscious/automatic learning. The results showed: (1) d-amphetamine facilitated response speed, whereas haloperidol inhibited it, in comparison to placebo; (2) the linear increase in procedural learning corresponded with pharmacological manipulation of degree of dopaminergic activity, i.e. subjects given haloperidol showed the least, and subjects given d-amphetamine the greatest, procedural learning. The implications of these findings are discussed in relation to investigation of abnormalities of procedural learning processes in schizophrenia. Received: 28 June 1996/Final version: 2 October 1996  相似文献   
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Perbendazole was given orally and subcutaneously to mice infected with Angiostrongylus cantonensis at different stages of infection. The subcutaneous route of administration was more effective than the oral one. On the 5th day after infection, the perbendazole had a higher efficacy than on the 10th day postinfection. This finding shows that perbendazole had complete larvicidal effect at early stages of infection.  相似文献   
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A retrospective review of the medical records of 114 malnourished and 106 non-malnourished male veterans assessed the inpatient and 1 year post-discharge dietetic care given for the treatment of malnutrition. The malnourished sample consisted of subjects discharged with a protein-energy or protein malnutrition comorbidity. Subjects in the diagnosis-matched and age-matched control sample were discharged without a malnutrition comorbidity during the same period. Data collected from progress notes included diagnoses, inpatient dietetic feedings and services provided, discharge dietetic care, intervening clinic visits, and rehospitalizations. On initial admission, 79% of the diagnoses for the malnourished group fell into five diagnosis categories: neoplasms; respiratory system diseases; digestive system diseases; endocrine, nutritional, and metabolic diseases; and mental disorders (including alcohol-related disorders). Malnourished subjects received more specialized feedings and dietetic services than did the controls on initial admission. However, the discharge and post-discharge care received by surviving members of both groups was similar. Fewer than half the members of either group received post-discharge care. Fifty-four malnourished and 54 control patients were hospitalized more than once. The findings indicate that levels of inpatient and outpatient dietetic care need to be coordinated to alleviate malnutrition.  相似文献   
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Norethisterone enanthate (NET-En), an established intramuscular long-acting contraceptive agent, has previously been shown to be effective in inhibiting fertility in two rodent species even 4 days after oral ingestion. Pharmacokinetics of NET and NET-En were studied after oral and intramuscular doses in two animal species and a few women. The results suggest that the NET-En was absorbed within a day in all the species after oral dose. The estimates of relative bioavailability ranged from 13 to 51% in rabbits, monkeys, and women. The elimination half-life was 5–10 days. The presence of the active component, NET, in the circulation over the experimental period of 15 days suggests that NET-En could be useful as a long-acting oral pill. The suppression of progesterone levels during the luteal phase of menstrual cycle in women also supports this finding.  相似文献   
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The serum apolipoprotein A (Apo A) and alpha-fetoprotein (AFP) were evaluated in histologically verified 30 cases of alcoholic cirrhosis and 18 cases of hepatocellular carcinoma (HCC). The latter were also divided into subgroups depending on the presence or absence of associated cirrhosis. Serum Apo A levels were found to be significantly decreased in cirrhotics (p less than 0.001) compared to controls and non-cirrhotic HCC patients. In 22 cases of alcoholic cirrhosis (AFP less than 10 ng/ml) and 12 cases of HCC (AFP greater than 600 ng/ml), the AFP levels itself were diagnostic, but in the remaining cases, AFP levels (100-600 ng/ml) were not able to differentiate between cirrhosis and malignancy. In this later group of patients with low pathological range of AFP, serum Apo A levels found to be significantly decreased in alcoholic cirrhotic patients (p less than 0.001) compared to HCC patients. Thus, estimation of Apo A levels may be helpful to interpret the AFP values at lower pathological range due to suspected liver pathology.  相似文献   
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Although most congenital heart defects are isolated abnormalities of embryonic development, with little genetic contribution, a small number are components of syndromes. In such cases, an accurate diagnosis has important implications for individual prognosis and familial genetic counseling. Alagille syndrome (AGS) is a dominantly inherited multisystem developmental disorder, which primarily affects the liver, heart, eyes, skeleton, and face. In recent years, the identification of the AGS gene has drawn attention to the existence of subclinical carriers, and broadened the spectrum of phenotypical variation associated with this syndrome. The authors present a case of mother and son with benign stenosis of the pulmonary artery branches. Subtle facial aspects suggested the diagnosis of AGS, which was confirmed by molecular analysis. Relevant clinical investigations and diagnostic implications are discussed.  相似文献   
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Ependymomas are glial neoplasms whose clinical behavior is difficult to predict based on histology alone. Recently, a comparative genomic hybridization study identified frequent chromosome 9p and 13q losses in anaplastic ependymomas, suggesting that p16 and RB alterations may be involved in tumor progression. In order to test this hypothesis further, 101 myxopapillary, conventional, and anaplastic ependymomas (51 spinal and 50 intracranial tumors) were tested for RB and p16 deletions using fluorescence in situ hybridization. Clinical follow-up, ranging from 2 to 198 months (median 46 months), was obtained in 90 cases (91%). RB and p16 deletions were seen in 22 of 92 (24%) and 22 of 89 (25%) informative cases, respectively. Polysomies were more frequent in the grade I and II spinal tumors, consistent with prior reports of increased aneuploidy in such cases. No significant genetic associations were seen with tumor grade, recurrence, or death, suggesting that 9p and 13q deletions do not play a prominent role in the malignant progression of ependymomas, as has been implicated in other glioma subtypes.  相似文献   
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