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Occupational disease surveillance data sources, 1985.   总被引:1,自引:1,他引:0       下载免费PDF全文
Health department epidemiologists in 50 states, New York City, and the District of Columbia were surveyed in 1985 about seven potential data sources for occupational disease surveillance. Reported sources of occupational disease data were: automated workers' compensation claims (63 per cent of the 52 respondents); provider reports (62 per cent); death certificates with occupation or industry (60 per cent); cancer registries with occupational histories (35 per cent); birth certificates with parent's occupation (27 per cent); non-cancer disease registries (13 per cent); and hospital or insurance records (8 per cent).  相似文献   
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Delivery of adenovirus, herpes simplex virus (HSV), and paramagnetic monocrystalline iron oxide nanoparticles (MION) to rat brain (n = 64) was assessed after intracerebral inoculation or osmotic disruption of the blood-brain barrier (BBB). After intracerebral inoculation, the area of distribution was 7.93 +/- 0.43 mm2 (n = 9) for MION and 9.17 +/- 1.27 mm2 (n = 9) for replication-defective adenovirus. The replication-compromised HSV RH105 spread to 14.00 +/- 0.87 mm2 (n = 8), but also had a large necrotic center (3.54 +/- 0.47 mm2). No infection was detected when virus was administered intra-arterially without hyperosmotic mannitol. After osmotic BBB disruption, delivery of the viruses and MIONs was detected throughout the disrupted cerebral cortex. Positive staining was found in 4 to 845 cells/100 microns thick coronal brain section (n = 7) after adenovirus administration, and in 13 to 197 cells/section (n = 8) after HSV administration. Cells of glial morphology were more frequently stained after administration of adenovirus, whereas neuronal cells were preferentially stained after delivery of both HSV vectors and MION. In a preliminary test of vector delivery in the feline, MION was detected throughout the white matter tracts after inoculation into normal cat brain. Thus MION may be a tool for use in vivo, to monitor the delivery of virus to the central nervous system. Additionally, BBB disruption may be an effective method to globally deliver recombinant viruses to the CNS.  相似文献   
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Histamine receptors are present in adrenergic terminals, and histamine is reported to inhibit release of the neurotransmitter norepinephrine (NE) at certain neuroeffector junctions. However, a physiological role for histamine in modifying adrenergic neurotransmission has not been established. To examine the interaction of elevated plasma histamine and catecholamine release, two compounds that release histamine, morphine (3 mg/kg), and compound 48/80 (0.5 mg/kg), were administered intravenously (i.v.). Plasma norepinephrine (NE) levels were used to monitor sympathetic nervous system activity, and plasma epinephrine (Epi) levels were used to monitor adrenal activity. Both morphine and compound 48/80 caused an immediate and marked increase in plasma histamine. Simultaneous with this increase, a marked decrease in mean arterial pressure occurred. Plasma NE levels increased in animals administered compound 48/80, but in morphine-treated animals, plasma NE levels did not change from pretreatment values. Plasma Epi levels increased in both groups, but the magnitude and duration of the responses differed. The results indicate that elevated plasma catecholamines can increase in response to histamine-induced hypotension but this effect can be suppressed by the central actions of morphine.  相似文献   
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Although millions of hypertensive individuals receive chronic treatment with antihypertensive medication, the effect on the central nervous system by these drugs is poorly understood. Such treatment, while generally well tolerated, frequently produces symptoms of drowsiness, weakness, altered memory and impaired concentration. In addition to subjective evidence derived from patient reports, a large number of investigations have now been published which attempt to objectively assess the influence of antihypertensive medication on behavioral or cognitive performance. This paper summarizes and critically evaluates experimental studies of the effect of antihypertensive medication on subjects' performance of neuropsychological tasks and reviews the pharmacologic mechanisms by which these drugs may affect behavior. The literature is incomplete in its assessment of all domains of neuropsychological performance and all drug classes, and methodologic deficiencies are common. Nonetheless, the consensus of all studies and the findings of well-designed studies in particular do not identify any notable areas of performance impairment in patients receiving antihypertensive medication. Moreover, results suggest that, in certain instances, drug treatment may even enhance performance. In light of the limitations of the literature, however, an adequate understanding of the effects of antihypertensive therapy on behavioral functioning awaits completion of large, well-designed investigations including all major drug classes and thorough neurobehavioral assessments.  相似文献   
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OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care.  相似文献   
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