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排序方式: 共有732条查询结果,搜索用时 15 毫秒
1.
M Susser 《The American journal of clinical nutrition》1991,53(6):1384-1396
The causal sequence maternal nutrition----maternal weight gain----infant birth weight is not sustained by available evidence except under extreme nutritional deprivation. For maternal weight change, diet effects of near starvation are unequivocal. With chronic undernutrition or social deprivation, diet effects are inapparent or modest (conditional on pregnancy stage, diet supplement, and prepregnancy weight). For birth-weight change, diet effects of near starvation are likewise unequivocal and modest with chronic undernutrition or social deprivation. The complete causal sequence has been demonstrated only below a famine threshold. Outside famine, effects are modest (conditional on baseline nutrition, timing, and content of diets, possibly also on infant sex and energy expenditure). High-protein concentrations have produced adverse effects. Micronutrients and consequent fluid retention could have favorable effects. Diet effects on birth weight apparently bypass maternal weight change. Hence, to enhance birth weight, maternal diet appears to deserve more attention than does weight gain. 相似文献
2.
Ezra Susser M.D. Dr.P.H. Molly T. Finnerty M.D. Nancy Sohler M.P.H. 《The Psychiatric quarterly》1996,67(3):165-176
This paper concerns the diagnostic classification of nonaffective acute remitting psychosis (NARP), which we also term acute brief psychosis. We argue that NARP can be delineated from both schizophrenia and the affective psychoses and considered as a single diagnosis. As indicated by the term NARP, four criteria would be central to the diagnosis: 1. nonaffective, 2. acute onset (over less than two weeks), 3. recovery within a brief duration (less than six months), and 4. psychosis broadly defined. We review the rationale and the empirical evidence for this proposed classification. 相似文献
3.
Golli M; Van Nhieu JT; Mathieu D; Zafrani ES; Cherqui D; Dhumeaux D; Vasile N; Rahmouni A 《Radiology》1994,190(3):741
4.
M Susser 《American journal of public health》1997,87(7):1091-1092
5.
6.
Kristine Jones Ph.D. Paul Colson Ph.D. Elie Valencia J.D. Ezra Susser M.D. Dr.P.H. 《The Psychiatric quarterly》1994,65(4):243-256
The Critical Time Intervention Project is a three-year clinical trial which tests a time-limited, supportive intervention
to reduce recurrent homelessness among mentally ill men moving from a shelter to the community. Along with a comparison of
nights spent homeless and other outcomes, the evaluation of the Critical Time Intervention includes a comparison of the relative
costs of the intervention, compared to usual treatment. Such cost effectiveness analyses are difficult to perform and are
rarely applied to mental health treatments. This paper presents the general scheme of this analysis and discusses critical
issues in the construction and measurement of cost variables. Preliminary results which have implications for the cost analysis
are presented. 相似文献
7.
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9.
Inhibition of 2-nitropropane-induced rat liver DNA and RNA damage by benzyl selenocyanate 总被引:5,自引:2,他引:3
We observed that pretreatment of male F344 rats with benzyl selenocyanate,
a versatile organoselenium chemopreventive agent in several animal model
systems, decreases the levels of DNA and RNA modifications produced in the
liver by the hepatocarcinogen 2- nitropropane. To clarify the mechanisms
involved, we pretreated male F344 rats with either benzyl selenocyanate,
its sulfur analog benzyl thiocyanate, phenobarbital or cobalt
protoporphyrin IX; the latter is a depletor of P450. We then determined (1)
the ability of liver microsomes to denitrify 2-nitropropane, (2) effects on
2-nitropropane- induced liver DNA and RNA modifications and (3) amount of
nitrate excreted in rat urine following administration of the carcinogen.
Pretreatment with benzyl selenocyanate or phenobarbital increased the
denitrification activity of liver microsomes by 217 and 765%, respectively,
increased liver P4502B1 by 31- and 435-fold, respectively, decreased the
levels of 2-nitropropane-induced modifications in liver DNA (29-70% and
17-30%, respectively) and RNA (67-85% and 30-50%, respectively), and
increased the 24-h urinary excretion of nitrate by 157 and 209%,
respectively. Pretreatment with benzyl thiocyanate had no significant
effect on any of these parameters. Pretreatment with cobalt protoporphyrin
IX decreased liver P4502B 1 by 87%, decreased the denitrification activity
of liver microsomes by 76%, decreased the 24 h urinary excretion of nitrate
by 88.5%, but increased the extent of 2-nitropropane-induced liver nucleic
acid modifications by 17-67%. These results indicate that the metabolic
sequence from 2-nitropropane to the reactive species causing DNA and RNA
modifications does not involve the removal of the nitro group. Moreover,
they suggest that benzyl selenocyanate inhibits 2-NP-induced liver nucleic
acid modifications in part by increasing its detoxication through induction
of denitrification, although it is evident that other mechanisms must also
be involved.
相似文献
10.
The problems of separating highly confounded hereditary and environmental factors are reviewed from an epidemiological point of view. Once the fact rather than the appearance of familial aggregation is established, one can search for and analyze strong indicators of either genetic or environmental effects, and ultimately attempt their separation by strong design. Indicators of genetic effects are classified according to the presence or absence of family recurrence. In the presence of family recurrence, three analytic approaches are available: segregation analysis, linkage, and heritability estimates. In the absence of family recurrence, biological markers and endogamous groups can be used. Indicators of environmental effects are also classified according to the presence or absence of family recurrence of a disorder. In the presence of family recurrence, three environmental indicators are considered: non-Mendelian clustering, such as time of onset versus age in family clusters, and sex clusters; cohabitational effects; and maternal transmission. In the absence of family recurrence, environmental indicators include secular trends, migration, time and place clusters, family size, and birth order. Designs that aim to separate heredity and environment include twin studies, fixed clusters that include a variety of degrees of relatedness (particularly the family set-design), and comparisons of separately reared relatives. The strengths and weaknesses of twin studies and family set designs are reviewed. Separately reared relatives provide the most cogent tests of genetic and environmental hypotheses. Among these, separated twin pairs, half-sibs, and relatives separated through institutional placement or adoption are considered. Adoption strategies are illustrated by the Danish adoption studies of schizophrenia, criminality, and alcoholism, and these studies are reanalyzed from the perspective of epidemiological case-control and cohort studies. Finally, the potential uses of multiple family settings as they occur in the general population are briefly discussed. 相似文献