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981.
The development of simple goiter in rabbits, which results when they are fed on a diet consisting chiefly of cabbage (or other Brassica) can be prevented by the feeding of certain fresh plants. Lawn grass, fresh alfalfa, skunk cabbage and steamed cabbage press juice have been found effective. Washing Brassicae with water improves their goiter-producing action, probably by the removal of goiter-preventing substances. The antigoitrous effect of plant juices was found to vary with the amount of reducing substance other than glutathione present. Skunk cabbage press juice, obtained from growing plants during the spring months, contained a large amount of iodine-absorbing material, and was very effective in involuting hyperplastic glands while juice obtained from mature plants in July when the iodine-absorbing material had nearly all disappeared, was quite ineffective. Certain extracts from cabbage administered parenterally, containing the reducing material, also had a marked involuting action on the thyroid. These extracts were practically iodine-free. The substance or substances believed to be responsible are easily soluble in water, ethyl alcohol, aqueous ethyl alcohol and are precipitable by lead acetate at a pH of 0.68–0.70. They are partially destroyed by exposure to air and by steam at 100°. Hexuronic acid isolated by Szent-Györgyi from cabbage, orange juice and suprarenal glands could be the antigoitrous agent. It cannot be glutathione.  相似文献   
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987.
A patient with severe ankylosing hyperostosis of the cervical spine is reported and the differential diagnosis discussed.  相似文献   
988.
This study examines the relative impacts of human capital and market conditions on the economic rents associated with hospital privileges in the market for footcare. An empirical model of hospital privileges for podiatrists is formulated based on the Pauly-Redisch model of hospital behavior. The privilege model is then incorporated into a model of podiatrists' earnings via a selection adjustment as proposed by Heckman and Lee. The results indicate the persistance of economic rents even after controlling for unobserved 'quality' factors.  相似文献   
989.
BACKGROUND: Brain serotonin neurotransmission and hypothalamic-pituitary-adrenal axis function are implicated in the pathophysiology of depression, and these systems interact in a reciprocal modulatory fashion. This study examined the effect of tryptophan depletion, which acutely reduces brain serotonin concentrations, on serial cerebrospinal fluid concentrations of corticotropin-releasing factor in healthy humans. METHODS: Five subjects completed a standard tryptophan depletion protocol, and four subjects participated in a comparison condition. Subjects underwent continuous sampling of cerebrospinal fluid via lumbar peristaltic pump. Concentrations of cerebrospinal fluid corticotropin-releasing factor were measured by radioimmunoassay. RESULTS: No mood changes were observed in either group. Tryptophan-depleted subjects exhibited significantly greater increases in corticotropin-releasing factor concentrations over time than subjects in the comparison condition. CONCLUSIONS: These findings highlight the potential importance of corticotropin-releasing factor and serotonin interactions and suggest that activation of corticotropin-releasing-factor-containing neurons could play a role in the emergence of mood symptoms following tryptophan depletion in vulnerable individuals.  相似文献   
990.

Introduction

African Americans' (AAs) late-onset Alzheimer's disease (LOAD) genetic risk profile is incompletely understood. Including clinical covariates in genetic analyses using informed conditioning might improve study power.

Methods

We conducted a genome-wide association study (GWAS) in AAs employing informed conditioning in 1825 LOAD cases and 3784 cognitively normal controls. We derived a posterior liability conditioned on age, sex, diabetes status, current smoking status, educational attainment, and affection status, with parameters informed by external prevalence information. We assessed association between the posterior liability and a genome-wide set of single-nucleotide polymorphisms (SNPs), controlling for APOE and ABCA7, identified previously in a LOAD GWAS of AAs.

Results

Two SNPs at novel loci, rs112404845 (P = 3.8 × 10?8), upstream of COBL, and rs16961023 (P = 4.6 × 10?8), downstream of SLC10A2, obtained genome-wide significant evidence of association with the posterior liability.

Discussion

An informed conditioning approach can detect LOAD genetic associations in AAs not identified by traditional GWAS.  相似文献   
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