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1.
Nitroso-aldicarb was tested for its ability to induce sister-chromatid exchanges (SCE) and cell-cycle delay in human peripheral blood lymphocytes in vitro. This derivative of aldicarb induced a dose-dependent increase in SCE values per cell. In addition, a slight decrease in the successive mitotic progression of cells in culture was observed.  相似文献   
2.
Ginseng has long been one of this country’s major botanical drugs in foreign trade. Once harvested only in the forests of the Eastern frontiers, it became a domesticated crop in the late 1800s and now is raised largely in northcentral Wisconsin. Growers there produce an estimated 90% of the cultivated ginseng in the United States. Most American ginseng has been consumed in the Orient, as is reflected in export records dating back to 1821. Over 95% of the nearly 21,000 metric tons (T) shipped in the period 1821–1983 went to the Far East. Hong Kong has served as the center for re-exporting ginseng to China and Southeast Asia. Ginseng has been used in Asia for many purposes, mostly as a curative agent. It has also gained increasing acceptance elsewhere in the world for its alleged value.  相似文献   
3.
Inbred mice with the mutation diabetes C57BL/KsJ db+/db+ and the mutation obese C57BL/6J ob/ob displayed a total liver mitochondrial capacity to oxidize glutamate or succinate which was approximately eight times greater than the capacity of the C57BL/6J +/+ control mice. This increase in oxidation capacity was estimated by multiplying the observed twofold increase in each of the following components: total liver weight, the mitochondrial protein content per gram of liver, and glutamate or succinate respiration activity per milligram of liver mitochondrial protein. No significant difference in liver mitochondrial function and capacity for oxidation was observed between db+/db+ and ob/ob mutants, which indicated that these results may be primarily mediated by the genetic factors responsible for obesity and hyperphagia in these mutants, and not by the genetic traits associated with diabetes. These findings may provide a biochemical foundation in support of the thrifty gene hypothesis.  相似文献   
4.
Blood samples from 1090 Mexican Indians belonging to the Chol, Chontal, Totonac, Huastec, Mixe, Mazatec, Zapotec, Mixtec, Chinantec, Nahua, Cora and Huichol linguistic groups, were obtained and examined in regard to the following blood group antigens: A, B. M, N, P, C, c, D, E, e, Fy(a), K and Di(a). The gene frequencies were similar to what has been described for other Amerindians; high values for O, M, CDe, cDE and Duffy; low to absent Kell and presence of Diego in variable amounts. The frequency of chromosomes CDE and cDe/cde was somewhat higher than usual and some of the tribes had relatively high frequencies of the A and B antigens. It was felt that variable degrees of non-Indian admixture was at least partially responsible for this situation. A previous study dealing with the distribution of abnormal hemoglobins and glucose-6-phosphate dehydrogenase deficiency in these same tribes, had strongly suggested the possibility of some Negro admixture in the Chontal, Nahua and Cora tribes. However, this was not specifically reflected in their blood group distribution. This served to emphasize the need of investigating as many markers as possible when trying to characterize a population.  相似文献   
5.
Oral and intravenous L-phenylalanine loading tests were performed in 13 Parkinsonian patients and in 12 control subjects matched for age and weight. The results showed a normal intestinal absorption and a normal elimination from plasma of phenylalanine in the Parkinsonian patients.  相似文献   
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7.
Aplysinopsins are tryptophan-derived natural products that have been isolated from a variety of marine organisms and have been shown to possess a range of biological activities. In vitro receptor binding assays showed that of the 12 serotonin receptor subtypes, analogues showed a high affinity for the 5-HT2B and 5-HT2C receptor subtypes, with selectivity for 5-HT2B over 5-HT2C. While no conclusions could be drawn about the number and position of N-methylations, bromination at C-4 and C-5 of the indole ring resulted in greater binding affinities, with Ki’s as low as 35 nM. This data, combined with previous knowledge of the CNS activity of aplysinopsin analogs, suggested that these compounds may have potential as leads for antidepressant drugs. Compounds 3c, 3u, and 3x were evaluated in the chick anxiety–depression model to assess their in vivo efficacy. Compound 3c showed a modest antidepressant effect at a dose of 30 nM/kg in the animal model.  相似文献   
8.

Objective:

We have previously shown that racial composition of behavioral intervention groups does not affect achieved weight loss. However, it is unclear if the race of the interventionist affects intervention outcomes. The objective of this analysis is to estimate the impact of race concordance between participant and interventionist on weight change in the initial weight loss phase (phase I) of the Weight Loss Maintenance trial (WLM).

Design and Methods:

A total of 1,685 overweight or obese adults (BMI 25‐45 kg/m2) who were taking medication for hypertension and/or dyslipidemia participated in phase I of the WLM trial. All participants received a 6‐month intensive behavioral intervention in groups of 15‐20 facilitated by a trained interventionist. The main outcome is change in weight at 6 months.

Results:

Participants were on average 55 years of age, 67% female and 44% African American (AA). Three of seventeen interventionists were AA, 14 were non‐AA. Seventy‐three percent of participants shared race concordance with the interventionist. There was a small but statistically significant difference in weight change of participants who were the same race as the interventionist (?5.84 kg, s.e. 0.17) as compared with those who were not race concordant (?5.04 kg, s.e. 0.33), a difference of 0.8 kg, (P = 0.04). The impact of concordance on weight change differed by race (i.e., interaction of race and concordance was significant, P = 0.02).

Conclusions:

In a post hoc analysis of a group‐based behavioral intervention, race concordance for non‐AA participants was associated with slightly greater weight loss. Race concordance was not associated with weight loss for AA participants.
  相似文献   
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10.
Visceral leishmaniasis (VL) is a systemic protozoan disease that is transmitted by phlebotomine sandflies. Poor and neglected populations in East Africa and the Indian sub-continent are particularly affected. Early and accurate diagnosis and treatment remain key components of VL control. In addition to improved diagnostic tests, accurate and simple tests are needed to identify treatment failures. Miltefosine, paromomycin and liposomal amphotericin B are gradually replacing pentavalent antimonials and conventional amphotericin B as the preferred treatments in some regions, but in other areas these drugs are still being evaluated in both mono- and combination therapies. New diagnostic tools and new treatment strategies will only have an impact if they are made widely available to patients.  相似文献   
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