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排序方式: 共有910条查询结果,搜索用时 15 毫秒
51.
OBJECTIVE: To examine the characteristics of 'diagnostic orphans' among cannabis users-those who report one or two symptoms of DSM-IV dependence but do not meet diagnostic criteria for DSM-IV abuse or dependence. METHOD: Data were collected from a representative population cohort of 1601 young adults aged 20-21 years. Those who reported that they had used cannabis at least weekly at some point within the past year were assessed for symptoms of DSM-IV cannabis abuse and dependence using the Composite International Diagnostic Interview. RESULTS: Approximately 2.8% of the cohort could be classified as diagnostic orphans, with another 3.0 and 7.5% meeting criteria for abuse and dependence, respectively. Diagnostic orphans were: similar to those who met criteria for cannabis abuse or dependence in terms of demographic characteristics; similar to those who met criteria for cannabis abuse in terms of cannabis use patterns; and similar to those who met criteria for abuse and dependence in their rates of heavy alcohol use and DSM-IV alcohol dependence. However, they did not appear to have elevated rates of illicit drug use or mental health problems compared to non users. CONCLUSIONS: Diagnostic orphans reported using cannabis in a manner similar to persons meeting criteria for cannabis abuse, and had similar rates of alcohol dependence and other illicit drug use. Strict adherence to DSM-IV diagnoses of abuse and dependence may overlook a substantial proportion of young persons who experience cannabis-related problems. There is a need to consider (a) subthreshold levels of cannabis-related problems among those seeking treatment for other problems; and (b) interventions for this group to prevent escalation of such problems. 相似文献
52.
53.
Induction of chromosome-specific aneuploidy and micronuclei in human lymphocytes by metabolites of 1,3-butadiene 总被引:5,自引:1,他引:5
1,3-Butadiene is a carcinogen in rodents, but its potential carcinogenicity
to humans remains controversial. Numerous studies have shown that butadiene
and its metabolites cause sister chromatid exchanges in vitro and in vivo.
To test for other types of genotoxicity, the micronucleus assay and
fluorescence in situ hybridization (FISH) have been used to detect
chromosome damage in human lymphocytes caused by two reactive metabolites
of butadiene, diepoxybutane (DEB) and monoepoxybutene (MEB). DEB (0.5-5.0
microM) significantly increased micronucleus formation 4- to 6-fold (P
<0.01) and MEB (1-500 microM) by 2- to 4-fold (P <0.01) over control
levels. The ability of DEB and MEB to induce aneuploidy of chromosomes 7,
8, 12, and X was examined using dual-color FISH in both interphase and
metaphase cells. These chromosomes were chosen because of their involvement
in leukemogenesis. Both DEB and MEB caused dose-dependent increases in
hyperdiploidy of chromosomes 12 and X, but had no discernible effect on
chromosomes 7 and 8. These results suggest that DEB and MEB cause
chromosome-specific aneuploidy in human cells. If formed in sufficient
amounts, DEB and MEB may produce chromosome damage of the type found in
leukemia following exposure to butadiene.
相似文献
54.
55.
MT Tauber C Pienkowski P Pigeon M Cataldi P Rochiccioli 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(S389):28-30
Six children presenting with partial growth hormone (GH) deficiency (mean GH peak in two different tests, 8.0 k1.3 μ g/l ) aged 8–10.3 years (mean, 2.7 ± 0.9 years) were treated for 6 months by continuous subcutaneous infusion of GH-releasing hormone(1–29)-NH, (GHRH(1–29)-NH2 ); 24-hour GH profiles and height velocity were measured. A biphasic effect of GHRH(1–29)-NH2 infusion was observed. After an early substantial increase in the 24-hour integrated concentration of GH, from 1.6 ± 0.1 to 3.5 ± 0.7 μg/l/minute, a subsequent consistent decrease occurred by 3 months, which was more pronounced after 6 months (mean 24-hour integrated concentration of GH, 1.9± 0.9 μg/l/minute). This effect reflects modification of both pulse amplitude and frequency of GH secretion. At the end of the study, one child had complete suppression of GH secretion and two others showed only one peak above 5 μg/1 during a 24-hour period. No correlation was found between these changes and height velocity. Three children did not grow significantly; the other three children who had a growth response to GHRH(1–29)-NH2 were those with the lowest 24-hour integrated GH concentration at the end of the study. The possible mechanisms involved in this biphasic effect, including GHRH antibodies, changes in somatostatin levels and/or desensitization of pituitary GHRH receptors, have been investigated. 相似文献
56.
Moderate and severe malnutrition are endemic in much of the developing world and in association with pockets of deprivation in the developed world. The cost in terms of individual and social development is high. The principles of effective management are clearly documented. A low cost, community based treatment programme for moderately and severely malnourished children under 3 years of age was established at a health centre in rural Jamaica. Children were followed up monthly and defaulters were rigorously recalled. Management consisted of carefully delivered dietary advice, antibiotics, anthelminthics, and vitamin supplements. All children improved and the response of 36 children, who were treated in the first year, showed an accelerated weight gain, with catch-up growth and the maintenance of length gain. There was a significant increase in the weight for age, at 1.9% per month over six months, which exceeds the rate reported with food supplementation programmes and nutrition rehabilitation centres. 相似文献
57.
MT Bardella N Molteni L Prampolini AM Giunta AR Baldassarri D Morganti PA Bianchi 《Archives of disease in childhood》1994,70(3):211-213
The use of follow up studies was evaluated in 128 patients with coeliac disease during their first visit to a department for adults. The original diagnosis had been made in childhood in all patients. Fifty eight (45%) of the subjects were following a gluten free diet, 23 (18%) were following a gluten free diet but with occasional gluten consumption, and 47 (37%) had adopted an unrestricted, gluten containing diet for a mean of 11.2 years. There was no correlation in individual subjects between the presence of symptoms, biochemical and immunological abnormalities, severity of histological findings, and the amount of dietary gluten, despite the greater frequency of symptoms in the group following an unrestricted diet than in the other two groups. Short stature and epilepsy with cerebral calcifications only occurred in patients following an unrestricted diet. As only diagnosis based on two or three biopsy samples and regular follow up correlated positively with dietary compliance, it is suggested that a histologically confirmed diagnosis of coeliac disease and regular lifelong follow up are essential in the management of these patients. 相似文献
58.
The survivorship method of analysis has been used to evaluate retrospectively the outcome of 1166 total hip arthroplasties performed in Taranaki between 1970 and 1989. There were 867 cemented Charnley, 105 Harris Galante and 92 cemented Muller prostheses. Outcome was determined in 99.1% of the cases. There were 72 failures in the Chamley group, resulting in an annual failure rate of 1.78% and a 15 year survival rate of 73%. There were 26 failures in the Muller group, an annual failure of 6.93% and an 11 year survival of 63%. At review none of the Harris Galante group had failed. Survival was affected by age, sex, hospital and surgeon. 相似文献
59.
Wooden foreign bodies in soft tissue: detection at US 总被引:4,自引:0,他引:4
60.