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排序方式: 共有338条查询结果,搜索用时 859 毫秒
1.
The impact of law enforcement activity on a heroin market 总被引:2,自引:2,他引:0
It may be argued that seizing large quantities of heroin being imported into the country should decrease its supply and hence increase its price, resulting in a reduction in the quantity of the drug being purchased or consumed. To date, however, there has been no empirical evidence that heroin seizures in Australia have any effect on the price of heroin at street level. This article describes a 2-year research study during which the price and purity of street-level heroin were regularly monitored. It was found that heroin seizures had no effect on the price, purity or perceived availability of heroin at street level. It was further found that admissions to methadone treatment were not affected by the price or perceived availability of heroin or by local arrests for heroin use/possession, nor was any relationship found between these arrests and the price of street-level heroin. Nevertheless, two-thirds of those who sought entry to local methadone programmes indicated the price as a reason for stopping using heroin. This paper argues that supply-side law enforcement should only be used as a strategy for maintaining high heroin prices if the demand for heroin can be shown to be price-elastic and, further, that the costs of such a strategy need to be weighed against the benefits. 相似文献
2.
WESTIN STEINAR; OSTENSEN ARNE IVAR; LOVSLETT KJELL; PRYTZ JACOB; TELJE JO; TELSTAD WENCHE; LIE ARNE 《Family practice》1988,5(4):244-252
Westin S, stensen A I, Lvslett K, Prytz J, Telje J, TelstadW and Lie A. A group-based training programme for general practitioners:a Norwegian experience. Family Practice 1988; 5: 244252. There are approximately 3000 general practitioners in Norway,serving a population of slightly above four million people.A three year postgraduate education scheme for general practitionershas been in effect since 1973, to be replaced by a five yearvocational training programme from January 1985, making generalpractice a fully recognized specialty from that date. The educationalrequirements consist of one year of hospital training, fouryears of training in general practice, and a total of 400 hoursof course education, mainly in clinical subjects. The core elementof the training is attendance at a group-based structured educationalprogramme of two years' duration. This article describes theconcepts and content of this decentralized group-based education,as well as some of the conflicting considerations which eventuallyled to this new Norwegian model of general practice training.The first evaluation studies indicate that the educational programmehas met a long standing need among general practitioners. 相似文献
3.
M Z SATTI P LIND B J VENNERVALD S M SULAIMAN A A DAFFALLA H W GHALIB 《Clinical and experimental immunology》1996,106(1):45-54
The present work comprises a longitudinal study of Schistosoma mansoni infection in occupationally hyper-exposed canal cleaners in the Sudan and the influence of chemotherapy on humoral immune parameters. The study groups included chronically infected canal cleaners (n = 19), newly recruited canal cleaners (n = 17), normally exposed adults (n = 31), school children (n = 46) and Sudanese negative controls (n = 48). Previous studies of the same canal cleaners have demonstrated that chronically infected canal cleaners were more resistant to reinfection than newly recruited canal cleaners. ELISA was used to detect specific IgE and IgG subclasses in response to whole worm antigen (WWH) and soluble egg antigen (SEA) before and 3 months after praziquantel treatment in the groups of canal cleaners and before and 1 year after treatment in normally exposed adults. When intensity of infection was correlated with IgE antibody response, the resistant group of canal cleaners (those who stopped passing ova after treatment) showed a significant positive correlation between intensity of infection and specific IgE to WWH (Spearman''s correlation coefficient = 0·49, P < 0·05) compared with a highly significant negative correlation in the susceptible group (acquired new infection after treatment, Spearman''s correlation coefficient = 0·94, P < 0·01). Normally exposed adults and school children had significantly less specific IgE to WWH than canal cleaners, while chronically infected canal cleaners had significantly higher levels of specific IgG1 to WWH than newly recruited canal cleaners and school children, and significantly higher levels of specific IgG4 to WWH than school children. There was a significant increase in specific IgG1 and IgG4 to WWH, 3 months after treatment, in newly recruited canal cleaners and a significant decrease, 1 year after treatment, in normally exposed adults. None of the groups studied after treatment showed a significant change in their specific IgE to WWH. Normally exposed adults had significantly lower levels of specific IgE to SEA than newly recruited canal cleaners, and significantly lower levels of specific IgG1 to SEA than other infected groups. Both newly recruited canal cleaners and school children had significantly higher levels of specific IgG2 to SEA than persons in other groups. Only small differences between groups were observed with regard to specific IgG3 and IgM to SEA. Specific IgG4 to WWH and SEA showed different patterns after treatment between the resistant and susceptible groups of canal cleaners. The resistant group maintained the same level of IgG4 to WWH after treatment compared with a significant increase in the susceptible group. On the other hand, levels of specific IgG4 to SEA showed a highly significant decrease after treatment in the resistant group. In contrast, the same antibody subclass increased after treatment in the susceptible group. Generally, results show an association between IgE and IgG1 responses to WWH and resistance to reinfection. In contrast, an association was observed between IgG2 and IgM responses to SEA and susceptibility to reinfection. 相似文献
4.
ARNE OHLSSON KATHERINE FONG MARY HANNAH ZAHAVA HEYMAN RON GONEN TOBY ROSE RANJIT BABOOLAL 《BJOG : an international journal of obstetrics and gynaecology》1991,98(7):692-697
Summary. Twenty-three pregnancies with fetuses at risk for pulmonary hypoplasia were studied weekly until delivery. The amount of time spent in fetal breathing activity was recorded under controlled conditions during 1 h using real-time ultrasound. An amniotic fluid index was determined. The clinicians and the pathologist were unaware of the ultrasound findings. Eight of 23 fetuses did not breathe at the last ultrasound examination. Three babies died of pulmonary hypoplasia and two of these showed fetal breathing before birth. The three deaths were associated with rupture of the membranes at <20 weeks gestation and of ≥44 days duration. One infant developed bronchopulmonary dysplasia. The amniotic fluid index in these four pregnancies was low and the newborn infants had limb contractures. Chorioamnionitis/funisitis was noted in 13 placentas. Eight fetuses were assessed for fetal breathing within 2 days of birth. The lack of fetal breathing had sensitivity, specificity, positive and negative predictive values of 0.75 for chorioamnionitis/funisitis. In this pilot study the absence of fetal breathing was of no value in predicting lethal pulmonary hypoplasia, but was related to chorioamnionitis/funisitis. We recommend further studies of fetal breathing in relation to fetal/neonatal infections. 相似文献
5.
The excretion pattern of intramuscularly injected cholic acid-24–14C was studied for 4 days after the injection in 10 cases of erythro-blastosis (EB). Seven patients with EB and raised serum conjugated bilirubin excreted 3643% of the injected isotope in the urine, whereas the amounts of isotope in the faeces varied greatly. In 3 cases without raised serum conjugated bilirubin less isotope was recovered in the urine and always more than 10% of injected isotope was recovered in the faeces. Cholic acid-24–14C was excreted essentially unchanged in all cases but in conjugated form. In all cases of EB the urine was found to contain bile acids, chiefly cholic acid. The infants with EB associated with cholestasis excreted 4.8–132.3 μmol of these acids per day; the corresponding values in the absence of cholestasis being 0.4–0.9 μmol per day. In the infants with physiological jaundice the excretion ranged from less than 0.01 to 0.7 μmol per day; the correspondign values in the 2 patients with hyperbilirubinaemia were about 0.2 μmol per day. The infants with EB associataed with cholestasis were found to excrete as large amounts of bile acids in the urine as the infants with intrahepatic cholestasis. These findings strongly suggest that increased serum conjugated bilirubin, irrespective of the patho-genesis of the liver damage, is associated with an impaired bile acid excretion to the intestine. EB without increased serum conjugated bilirubin did not seem to alter the bile acid metabolism, since the urinary excretion of cholic acid and chenodeoxycholic acid in these cases was practically the same as in jaundiced newborn infants. 相似文献
6.
This series included 24 infants, 16 boys and 8 girls, who were admitted to hospital with the diagnosis of obstructive jaundice. Five of the infants were subsequently found to have extra-hepatic biliary atresia (BA) and the other 19 infants intrahepatic cholestasis of infancy (IHC). The infants were investigated given special attention to: the quantitative urinary excretion of cholic and chenodeoxycholic acids, the isotope excretion after intramuscular injection of cholic acid-24–14C, the nature of labelled urinary bile acids, the half-life and the pool size of cholic acid. At the first examination of the infants after admission the urinary excretion of cholic and chenodeoxycholic acids varied greatly between the patients. However, on comparing the values obtained in the two groups, it was found that there was virtually no difference between the mean daily values of cholic and chenodeoxycholic acids in urine, and the ratio cholic to chenodeoxycholic acid between the BA group and the IHC group. After the injection of isotopic cholic acid most of the isotope was recovered in the urine in all cases. In the infants with BA the faecal excretion of the isotope was low, being less than 3 per cent of the injected isotope. Out of the 19 infants with IHC the recovery of the injected isotope in faeces was also less than 3% in 11 infants. In 8 infants with IHC the faecal isotope excretion was significantly high to exclude extrahepatic biliary atresia. The first 24 hour urine specimen contained small amounts of unconjugated labelled cholic acid in all cases whereas in no case did the patients excrete unconjugated labelled cholic acid 48 hours after the injection of the isotope. No transformation of cholic acid was observed. There was no difference between the BA group and IHC group with regard to the percentage labelled glycine conjugates of total excreted urinary conjugates. Neither was there any difference between the two groups with regard to half-life and pool size of cholic acid. There was no difference with respect to the bile acid metabolism between infants with congenital CMV infection, decreased serum concentrations of alfal-antitrypsin and the other patients. 相似文献
7.
8.
T. LIND J. GERRARD T. S. SHERIDAN W. WALKER 《Acta paediatrica (Oslo, Norway : 1992)》1977,66(3):333-337
Abstract. Coulter Counter (Model S) analysis of 400 cord blood samples are presented, together with differential white cell counts for 249 of these. The mean values for haemoglobin and red cell count are somewhat higher than previous values determined by manual methods, while those for haematocrit and mean cell volume are slightly lower. An unexpected finding was that the red cell count, haemoglobin concentration, and haematocrit, are significantly higher in male than in female infants. A parity effect was also demonstrated: infants of both sexes born as second or subsequent births had lower values for total white cell count, haemoglobin concentration and haematocrit, than first-born infants. 相似文献
9.
Fifteen human monoclonal IgM proteins could be divided into two groups based on their ability to inhibit binding of a labelled human monoclonal IgM (IgM-Se) to Staphylococcus aureus Cowan 1 (IgM-Se assay); seven were positive and eight were negative. We found complete agreement between positive reaction in the IgM-Se assay, the presence of protein A reactivity in gel diffusion experiments, and high titres in an indirect haemagglutination test detects antibodies to protein A-IgG complexes. The protein A precipitation patterns of IgM and autologous IgG were not identical. 相似文献
10.