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71.
The aim of this study was to determine the number and size of apical non-myelinated (C) axons of healthy human premolars. The material was derived from a large collection of specimens prepared for a previous quantitative investigation on the myelinated (A) axons of human premolars. A total of 16 teeth (six maxillary first and five each of mandibular first and second premolars), removed from adolescents for orthodontic reasons, were used. Root discs of about 0.6 mm thickness were prepared at about 2 mm cervical to the root apex and processed for light and electron microscopy. The number of non-myelinated axons was determined by taking a total census of such fibres that could be identified and reconstructed by standardized composite electron micrographs from each root disc. The measurement of axons was done on a statistically representative sample of axons (n=1810) using an electronic image processing unit. The 16 teeth had an average of 2000 ± 1023 non-myelinated axons at the juxta-apical level (range 534–3912). The average diameter of the non-myelinated axons was found to be 0.5 ± 0.4 m (range 0.05–2.4 m). 相似文献
72.
21世纪卫生系统改革对卫生经济学发展的影响 总被引:2,自引:0,他引:2
该文介绍了发达国家和发展中国家在卫生改革中遇到的问题。前者有:组建医院间“战略联盟”,管理保健市场发展,卫生服务效率、公平性和可及性等。后者有:减少政府的作用,改变公共部门的组织及管理,增加卫生资金的来源及数量。这些问题引起卫生经济学界关注。第二次国际卫生经济学会会议将讨论以下专题:信息不对称及卫生保健组织间关系、卫生保健的选择,卫生及卫生服务的需求,健康及卫生服务的分布,卫生保健的经济学评价,卫生保健市场分析,健康保险,管理保健,卫生服务的产出等18个主题。 相似文献
73.
Background and purposePhysical exercise is one of the most effective interventions to reduce fibromyalgia symptoms. Previous studies have reported benefits of dance-based intervention on the fibromyalgia impact, health-related quality of life and pain, regardless the interventions were based on creative- or repetitive dance. This study aimed to compare the effectiveness of creative and repetitive dance interventions.MethodsPRISMA guidelines were followed in this systematic review. The Cochrane Library, PubMed, Trip, Google Scholar, Web of Science (WOS), Embase and Scopus databases were selected to identify potential articles. Studies were included if they met the following inclusion criteria: to be a clinical trial or a randomized controlled trial, include people with fibromyalgia, have a comparison group and evaluate the impact of the disease, pain or quality of life. Fifteen articles fulfilled the inclusion criteria. The methodological quality of the studies was assessed using the Cochrane Collaboration's tool.ResultsDance-based interventions significantly reduced fibromyalgia impact (standardized mean difference = −0.69), pain (standardized mean difference = −0.70 and increased quality of life (standardized mean difference = 0.43) of people with fibromyalgia. The effectiveness of dance interventions is increased when a creative component is added, since it can lead to higher improvements in pain, impact of the disease and improving quality of life.ConclusionDance-based interventions are significantly effective in reducing the impact of fibromyalgia, pain as well as increasing health-related quality of life. Subgroup analyses suggest that creative dance-based interventions could be more effective than repetitive dance-based interventions to reduce pain and fibromyalgia impact. However, results must be taken with caution due to the large heterogeneity and the small number of articles. 相似文献
74.
Summary The primary objective of this study was to determine the number and size of myelinated nerve fibers at the subcervical, midroot and juxta-apical levels of human premolars. Sixty-seven healthy premolars extracted from adolescents were utilized. Root-discs were prepared from the three sites and processed for light and electron microscopy. The myelinated nerve fibers were counted from semithin sections using a sampling microscope. The measurements were taken from composite electron micrographs using an electronic image processing unit. A total of 1883 myelinated axons from seven mandibular second premolars was gauged. The 67 teeth had an average of 312±149 myelinated nerve fibers at the juxta-apical level (range 18 to 728). The contra- and ipsilateral differences in means among the four groups of premolars were not significant (P>0.05). The number of nerves increased significantly (P<0.05) toward midroot and subcervical (P<0.001) levels in all groups. The average neural diameter was 3.51.0 m at the juxta-apical level, and the between-teeth difference in mean was found to be significant (P<0.01). There was no decline (P>0.05) in the diameter of myelinated nerve fibers toward midroot and subcervical levels. 相似文献
75.
Relationship between lower limb dynamics and knee joint pain 总被引:6,自引:0,他引:6
E L Radin K H Yang C Riegger V L Kish J J O'Connor 《Journal of orthopaedic research》1991,9(3):398-405
To test the hypothesis that appropriate and timely neuromuscular control of limb motions plays an important role in the preservation of joint health, we kinematically and kinetically examined the behavior of the legs of young adult subjects at heel strike during natural walking. We compared a group of 18 volunteers, who, we presumed, were preosteoarthrotic because of mild, intermittent, activity-related knee joint pain, with 14 age-matched asymptomatic normal subjects. The two groups of subjects exhibited similar gait patterns with equivalent cadences, walking speeds, terminal stance phase knee flexion, maximum (peak) swing angular velocity, and overall shape of the vertical ground reaction. However, our instrumentation detected statistically significant differences between the two groups within a few milliseconds of heel strike. In the knee pain group, the heel hit the floor with a stronger impact in this brief interval. Just before heel strike, there was a faster downward velocity of the ankle with a larger angular velocity of the shank. The follow-through of the leg immediately after heel strike was more violent with larger peak axial and angular accelerations of the leg echoed by a more rapid rise of the ground reaction force. This sequence of events represents repetitive impulsive loading, which consistently provoked osteoarthrosis in animal experiments. We refer to this micro-incoordination of neuromuscular control not visible to the naked eye as "microklutziness." 相似文献
76.
Seasonality of diarrhetic shellfish poisoning at a coastal lagoon in Portugal: rainfall patterns and folk wisdom. 总被引:3,自引:0,他引:3
Of the three types of toxicity known so far in Portuguese shellfish, only diarrhetic shellfish poisoning (DSP) and amnesic shellfish poisoning (ASP) are produced by microalgae that seem to have been present in the last decades or centuries. The most important paralytic shellfish poisoning (PSP) producer, Gymnodinium catenatum, is hypothesised to have been introduced quite recently as only in 1976 PSP toxicity was detected for the first time in shellfish from Galicia, NW Iberian Peninsula. While ASP presents very short episodes of contamination, the concentration of DSP toxins in some years surpasses human safety values for much longer periods. It is traditionally stated that shellfish should be consumed in 'months with R' (September-April). A retrospective study of the maximum monthly DSP levels attained in mussels from a coastal lagoon-Ria de Aveiro-between 1994 and 2001, showed that the highest frequency of months with concentrations surpassing the safety level of 2 microg/g digestive glands were found in June-September, followed by May and October. These months correspond with the months of lowest historical average rainfall in the period 1941-1998.Oscillations in the rainfall pattern coincided with earliest (or latest) detection by HPLC of DSP toxins in mussel in the years studied. In a semi-closed lagunar environment prone to in situ growth of DSP-producer microalgae, like Dinophysis acuminata, rainfall affects river output, lowering salinity and disrupting water column stability that favours Dinophysis growth. The seasonality of DSP recurrence may be connected to the folk adage on safety of shellfish consumption, after many years of empirical observations by coastal populations of diarrhoea episodes in summertime. 相似文献
77.
Krithika Rajagopalan PhD Linda Abetz MA Polyxane Mertzanis MPH Derek Espindle MA Carolyn Begley OD MS Robin Chalmers OD Barbara Caffery OD MS Christopher Snyder OD MS J. Daniel Nelson MD Trefford Simpson PhD Timothy Edrington OD MS 《Value in health》2005,8(2):168-174
OBJECTIVE: The purpose of this study was to compare the discriminative properties of two generic health-related quality of life (QoL) instruments (SF-36 and EQ-5D) and a newly developed disease-specific patient-reported outcomes instrument (Impact of Dry Eye on Everyday Life (IDEEL)) to distinguish between different levels of dry eye severity. METHODS: Assessment of 210 people: 130 with non-Sjogren's Keratoconjunctivitis Sicca (non-SS KCS), 32 with Sj?gren's Syndrome (SS) and 48 controls; comparison of SF-36, EQ-5D, and IDEEL age-adjusted data by dry eye severity levels. Severity was assessed based on diagnosis (non-SS KCS, SS, control), patient-report (none, very mild, mild, moderate, severe, extremely severe) and clinician-report (none, mild, moderate, severe). RESULTS: Discriminative validity results were consistent for all instruments. Significant differences between severity levels were found with most SF-36 scales (P < 0.05), all EQ-5D scales (P < 0.05), and all IDEEL scales (P < 0.0001), except for Treatment Satisfaction. IDEEL scales consistently outperformed the generic QoL measures regardless of the severity criterion used. Most SF-36 scales outperformed the EQ-5D QoL scale, but the EQ-5D visual analog scale outperformed the SF-36 scales, except for General Health Perceptions. CONCLUSIONS: The disease-specific IDEEL scales are better able to discriminate between severity levels than the majority of the generic QoL scales. Preliminary evidence demonstrates that the IDEEL will be sensitive to QoL changes over time, although further testing in controlled longitudinal studies is needed. 相似文献
78.
PURPOSE: To assess the health status of patients after a single seizure. METHODS: We compared single-seizure patients (SS) with patients who had well-controlled epilepsy (WC), and uncomplicated hypertension (HT). Patients were adults screened from emergency and outpatient units of two urban teaching hospitals using predefined criteria. The 83 patients (SS, 30; WC, 29; HT, 24) were interviewed by phone about functional status (SF-36), comorbid illness, cause of illness, number of visits to health providers, and drug side effects. RESULTS: No significant differences were found among groups for health status, SF-36 domain, or occurrence of drug side effects. SS patients had significantly lower scores on vitality (p < 0.03) and a trend toward lower role physical function (p < 0.07) compared with age-adjusted population norms. SS reported more visits to health providers than WC or HT, and the number of visits remained high at interview 1 year later. Patient knowledge of the "reason" for the seizure was not associated with health status or number of visits. CONCLUSIONS: Health status of patients within 1 year of a single seizure is similar to that of patients with well-controlled epilepsy or hypertension, but SS patients have greater health care utilization. 相似文献
79.
80.
目的探讨骨形成蛋白(BMP)超家族的成员BMP-2在大鼠正畸牙齿移动过程中牙周组织的分布和表达。方法用链霉亲和素生物素复合物(SABC)免疫组织化学法,检测实验性大鼠正畸牙齿移动过程中牙周组织BMP-2的表达。结果BMP-2在正畸牙齿加力各个时期存在特异的分布模式。正常牙周组织中主要分布于牙周膜,加力后张力区染色深,压力区为阴性。结论BMP-2参与了大鼠正畸牙齿移动骨改建过程,起非常重要的作用。 相似文献