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91.
The controversy surrounding fluoridation persists. In recent years opponents of fluoridation have resorted to the courts with increasing frequency and have achieved a few victories in the trial courts. To date, however, no appellate court has ruled against fluoridation. This article discusses the constitutional basis for the court decisions upholding fluoridation and the main arguments put forth by the antifluoridationists. Five of the more recent cases are summarized, as is the first fluoridation case to be appealed to the US Supreme Court. The article concludes that the legal validity of fluoridation in the United States has been thoroughly tested in the courts and confirmed. It appears that the antifluoridationists will concentrate their future legal attacks on the "harmful effects" of fluoridation on health and the environment. If they can convince the courts that even a few people were truly harmed, the delicate balance between the rights of the state to fluoridate in order to protect the public's health and the rights of the individual not to be harmed could well shift. In closing, the question is raised whether the US Congress has the power to pass legislation either to mandate or forbid fluoridation. 相似文献
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93.
Hong Liang TEY Hock Leong EE Andy SL TAN Thiam Seng THENG Su Ni WONG Shih Wee KHOO 《The Journal of dermatology》2010,37(5):426-430
The aim of this study was to determine if the following characteristics were associated with the presence of psoriatic arthritis in a sample of psoriasis patients: race, family history of psoriasis and psoriatic arthritis, age of onset of psoriasis, smoking, alcohol consumption and the maximum body surface area (BSA) affected by psoriasis. This was a case–control study involving 400 psoriasis patients who attended the Psoriasis and Photo‐medicine clinic in the National Skin Center of Singapore over a 1‐year period. Cases were psoriasis patients with psoriatic arthritis while controls were psoriasis patients without psoriatic arthritis. The diagnosis of psoriatic arthritis was made by rheumatologists and participants completed a self‐administered standardized questionnaire. The maximum BSA involved was determined from the case notes. Psoriatic arthritis was not significantly associated with sex, race, age of onset of psoriasis, a family history of psoriasis, smoking and alcohol consumption but was significantly associated with a family history of psoriatic arthritis (P < 0.001) and the maximum body surface involved (P = 0.05). Using multivariate analysis to control for variables, the presence of psoriatic arthritis was significantly associated with a family history of psoriatic arthritis (odds ratio [OR] = 20.5; 95% confidence interval [CI] = 2.49–169.10) and the maximum BSA involved (OR = 2.52; 95% CI = 1.33–4.75). Indian psoriatic patients were more likely to have psoriatic arthritis compared to the other races. A family history of psoriatic arthritis and a greater maximum body surface involved may be associated with having psoriatic arthritis in this study population of psoriasis patients. 相似文献
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E R Block J M Patel N P Sheridan 《Laboratory investigation; a journal of technical methods and pathology》1986,54(2):146-153
We evaluated the ability of endotoxin to protect against hyperoxic depression of plasma membrane fluidity in endothelial cells and fibroblasts in culture. Second- to-fifth passage porcine aortic endothelial cells and human newborn foreskin fibroblasts with 20 ng/ml of endotoxin or diluent in the culture medium were exposed to 20% O2 (control) or 95% O2 (hyperoxic) in 5% CO2 for 4 hours. After exposure, cells were labeled with 1,6-diphenyl-1,3,5-hexatriene (DPH), an aromatic hydrocarbon that partitions into the hydrophobic core of lipid bilayer membranes, or transparinaric acid (TPA), a natural, conjugated fatty acid that orients parallel to fatty acyl chains of membrane phospholipids. Membrane fluidity was monitored by measuring changes in the steady state fluorescence anisotropies (rs) for DPH and for TPA by using fluorescence spectroscopy. Reductions in membrane fluidity increase the value of rs. Addition of endotoxin to the culture medium of control endothelial cells and fibroblasts had no effect on rs for DPH or TPA. In hyperoxic endothelial cells, rs for DPH and rs for TPA were increased (p less than 0.001). Addition of endotoxin to the medium of hyperoxic endothelial cells prevented the increases in rs for DPH and TPA. Hyperoxia increased rs for DPH (p less than 0.003) but not rs to TPA in fibroblasts, and endotoxin failed to prevent this increase. These results indicate that hyperoxia decreases plasma membrane fluidity in endothelial cells and fibroblasts and demonstrate that endotoxin prevents the decrease in plasma membrane fluidity in endothelial cells, but not in fibroblasts. These membrane-protective effects may represent an alternative mechanism by which endotoxin protects against hyperoxic cellular injury, and this mechanism may be specific for hyperoxic injury to endothelial cells. 相似文献
96.
The role of Clock in the developmental expression of neuropeptides in the suprachiasmatic nucleus 总被引:4,自引:0,他引:4
Herzog ED Grace MS Harrer C Williamson J Shinohara K Block GD 《The Journal of comparative neurology》2000,424(1):86-98
The suprachiasmatic nucleus (SCN) is the dominant circadian pacemaker in mammals. To understand better the ontogeny of mouse SCN and the role of the pacemaker in peptide expression, the authors examined the distribution of cells that were immunoreactive for vasopressin (AVP) or vasoactive intestinal polypeptide (VIP) in wild type and Clock mutant mice at two developmental stages. Clock homozygous mice failed to show the dramatic increase in the number of VIP-immunoreactive (VIP-ir) neurons from postnatal day 6 (P6) to P30 that was found in the SCN of wild type mice. The number of AVP-ir neurons was relatively constant in the postnatal SCN but was significantly reduced in Clock/Clock mice. The effects of the Clock mutation varied with position in the SCN for both peptides. Densitometry of immunolabeled brains indicated that the Clock mutation reduced AVP expression specifically in the SCN and not in other brain areas. The SCN did not significantly change shape or size with age or Clock genotype. Taken together, these results indicate that the neonatal mouse SCN has its full complement of cells, some of which are not yet mature in their neuropeptide content. Furthermore, the observation that the Clock mutation appears to act on a subset of AVP and VIP cells suggests heterogeneity within these cell classes in the SCN. 相似文献
97.
98.
Ebner F Tepest R Dani I Pfeiffer U Schulze TG Rietschel M Maier W Träber F Block W Schild HH Wagner M Steinmetz H Gaebel W Honer WG Schneider-Axmann T Falkai P 《Schizophrenia Research》2008,104(1-3):71-78
BACKGROUND: Hippocampal volume reduction is a well replicated finding in schizophrenia. Evidence indicates a contribution of genetic and environmental factors, especially the influence of obstetric complications to this volume reduction. The aim of this study was to compare hippocampal volume of schizophrenic patients as well as and their relatives with control subjects and to quantify the additional contribution of obstetric complications. METHODS: T1 weighted MRI brain scans of 50 schizophrenic patients, 88 first-degree relatives and 53 healthy control subjects were used to perform volumetric measurements on the left and right hippocampus. A set of clinical measures including obstetric complications were recorded for all family members. RESULTS: Numerically our measurements revealed a hippocampal volume reduction in schizophrenic patients (left: - 14%, right: - 15%) and, although less pronounced, in their unaffected relatives (left: - 6%, right: - 10%). Noted differences in hippocampal volume between schizophrenic patients and controls were only significant for the left side. Hippocampal volumes of patients and their relatives with obstetric complications were reduced bilaterally. CONCLUSIONS: Hippocampal volume reduction is present in schizophrenic patients and their first-degree relatives, suggesting an influence of genetic factors.. In addition, however, obstetric complications have also been shown to play a major role. 相似文献
99.
100.