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31.
软骨修复组织蛋白多糖代谢与一氧化氮合酶抑制剂的影响   总被引:3,自引:0,他引:3  
目的:应用一氧化氮合酶抑制剂可改善骨性关节炎和风湿性关节炎软骨的代谢,作者前期的实验也证明一氧化氮合酶抑制剂能提高软骨修复组织的质量。实验进一步观察一氧化氮合酶抑制剂对软骨修复组织蛋白多糖代谢的影响。方法:实验于1999-06/2002-02在南方医科大学完成。①实验分组:取雄性新西兰兔24只,8月龄,体质量(2.5±0.2)kg。随机抽签法分为对照组、骨形态发生蛋白组和S-甲基异硫脲组,每组8只。②实验方法:将大白兔双侧股骨髁间关节面造成全层软骨缺损,对照组:软骨缺损不充填任何物质;骨形态发生蛋白组:缺损用骨形态发生蛋白纤维蛋白凝胶复合物充填;S-甲基异硫脲组:缺损应用胶原复合骨形态发生蛋白充填,术后按5mg/(kg·12h)皮下注射S-甲基异硫脲。术后1年麻醉后处死动物。③实验评估:应用组织切片番红O-快绿染色和图像分析技术,按照染色百分率、平均灰度(平均染色程度)和染色厚度(软骨厚度)指标来检测糖胺聚糖含量;应用Na235SO4掺入法检测软骨修复组织蛋白多糖合成。结果:纳入新西兰兔24只,均进入结果分析。①术后1年,对照组几乎无红色染色区域;骨形态发生蛋白组可见到少量的不均匀红色区域;S-甲基异硫脲组可见到较多均匀一致的红色染色区域。②S-甲基异硫脲组软骨修复组织番红O染色百分率为89.28%,明显高于骨形态发生蛋白组36.54%和对照组13.4%,S-甲基异硫脲组修复组织番红O-快绿染色平均灰度值134.5,分别为骨形态发生蛋白组平均灰度值56.8的2.5倍,为对照组26.4的7倍。软骨平均厚度S-甲基异硫脲组1.75cm分别为骨形态发生蛋白组0.76cm和对照组0.25cm的2倍和6倍。③Na235SO4掺入法结果显示,S-甲基异硫脲组[35S]摄入量明显高于骨形态发生蛋白组和对照组(P<0.01)。结论:诱导型一氧化氮合酶抑制剂S-甲基异硫脲的应用能明显增加软骨修复组织糖胺聚糖含量和蛋白多糖合成,对于软骨修复质量的提高有积极意义。  相似文献   
32.
Introduction: Pancreatic cancer (PC) has a dismal prognosis, with identified disparities in survival outcomes based on demographic characteristics. These disparities may be ameliorated by equitable access to treatments and health services. This systematic review identifies patient and service-level characteristics associated with PC health service utilisation (HSU). Methods: Medline, Embase, CINAHL, PsycINFO and Scopus were systematically searched between 1st January, 2010 and 17 May, 2021 for population-based, PC studies which conducted univariable and/or multivariable regression analyses to identify patient and/or service-level characteristics associated with use of a treatment or health service. Direction of effect sizes were reported in an aggregate manner. Results: Sixty-two eligible studies were identified. Most (48/62) explored the predictors of surgery (n=25) and chemotherapy (n=23), and in populations predominantly based in the United States of America (n=50). Decreased HSU was observed among people belonging to older age groups, non-Caucasian ethnicities, lower socioeconomic status (SES) and lower education status. Non-metropolitan location of residence predicted decreased use of certain treatments, and was associated with reduced hospitalisations. People with comorbidities were less likely to use treatments and services, including specialist consultations and palliative care but were more likely to be hospitalised. A more recent year of diagnosis/year of death was generally associated with increased HSU. Academically affiliated and high-volume centres predicted increased treatment use and hospital readmissions. Conclusion: Findings of this review may assist identification of vulnerable patient groups experiencing disparities in accessing and using treatments and therapies.  相似文献   
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Aims   To examine the hypothesis that increases in UK liver deaths are a result of episodic or binge drinking as opposed to regular harmful drinking.
Design   A prospective survey of consecutive in-patients and out-patients.
Setting   The liver unit of a teaching hospital in the South of England.
Participants   A total of 234 consecutive in-patients and out-patients between October 2007 and March 2008.
Measurements   Face-to-face interviews, Alcohol Use Disorders Identification Test, 7-day drinking diary, Severity of Alcohol Dependence Questionnaire, Lifetime Drinking History and liver assessment.
Findings   Of the 234 subjects, 106 had alcohol as a major contributing factor (alcoholic liver disease: ALD), 80 of whom had evidence of cirrhosis or progressive fibrosis. Of these subjects, 57 (71%) drank on a daily basis; only 10 subjects (13%) drank on fewer than 4 days of the week—of these, five had stopped drinking recently and four had cut down. In ALD patients two life-time drinking patterns accounted for 82% of subjects, increasing from youth (51%), and a variable drinking pattern (31%). ALD patients had significantly more drinking days and units/drinking day than non-ALD patients from the age of 20 years onwards.
Conclusions   Increases in UK liver deaths are a result of daily or near-daily heavy drinking, not episodic or binge drinking, and this regular drinking pattern is often discernable at an early age.  相似文献   
36.
An enquiry into sudden infant death syndrome (SIDS) in 1987 furnished us with detailed epidemiological data for 281 cases that underwent a thorough post-mortem examination. This analysis uses these data to evaluate the role the autopsy plays in explaining sudden death. The cases were classified into three diagnostic groups: explained causes of death (group 1), unexplained deaths with anomalies (group 2), and no anomaly (group 3). These 281 cases show the three essential features that characterize SIDS: over-representation of males, increased deaths during the second and third months of life, and increased deaths during winter. The autopsy examination revealed that many of these deaths had a medical explanation. Almost half were assigned to group 1. At the time of autopsy, no precise pathology could be diagnosed for 147 deaths; of these, 140 showed histological anomalies. There were only seven sudden deaths for which no abnormal sign was evident at the autopsy. These results are compared with those of similar studies and discussed in connection with three factors: the initial selection of cases, the nature and degree of the investigations, and the possible interpretations of the symptoms uncovered.  相似文献   
37.
From the statistics of the medical causes of deaths and the results of a retrospective survey carried out among the physicians who certified the deaths, an analysis of post-neonatal mortality during winter of 1986 was undertaken in order to know if the relative part of the sudden infant death syndrome (SIDS) had increased during that winter. It appeared that the deaths attributed to SIDS can be distinguished from deaths of other causes for several factors (place of death, former status of the baby). However, the low number of post mortem examinations performed does not allow in all the declared cases to assess SIDS as internationally defined. However, it is shown that sudden mortality was not higher during this special winter and that immunizations were not more frequently related to this cause than to other causes of death.  相似文献   
38.
The physiological role of basal laminae (BL) and connective tissue (meninges and their projections) in the adult brain is unknown. We recently described novel forms of BL, termed fractones, in the most neurogenic zone of the adult brain, the subependymal layer (SEL) of the lateral ventricle. Here, we investigated the organization of BL throughout the hypothalamus, using confocal and electron microscopy. New types of BL were identified. First, fractones, similar to those found in the lateral ventricle wall, were regularly arranged along the walls of the third ventricle. Fractones consisted of labyrinthine BL projecting from SEL blood vessels to terminate immediately beneath the ependyma. Numerous processes of astrocytes and of microglial cells directly contacted fractones. Second, another form of BL projection, termed anastomotic BL, was found between capillaries in dense capillary beds. The anastomotic BL enclosed extraparenchymal cells that networked with the perivascular cells coursing in the sheaths of adjacent blood vessels. Vimentin immunoreactivity was often detected in the anastomotic BL. In addition, the anastomotic BL overlying macrophages contained numerous fibrils of collagen. We also found that the BL located at the pial surface formed labyrinthine tube-like structures enclosing numerous fibroblast and astrocyte endfeet, with pouches of collagen fibrils at the interface between the two cell types. We suggest that cytokines and growth factors produced by connective tissue cells might concentrate in BL, where their interactions with extracellular matrix proteins might contribute to their effects on the overlying neural tissue, promoting cytogenesis and morphological changes and participating in neuroendocrine regulation.  相似文献   
39.
Cytogenesis in adult peripheral organs, and in all organs during development, occurs nearby basal laminae (BL) overlying connective tissue. Paradoxically, cytogenesis in the adult brain occurs primarily in the subependymal layer (SEL), a zone where no particular organization of BL and connective tissue has been described. We have reinvestigated the anatomy of the area considered the most neurogenic in the adult brain, the SEL of the lateral ventricle, in zones adjacent to the caudate putamen, corpus callosum, and lateral septal nucleus. Here, we report structural (confocal microscopy using laminin as a marker) and ultrastructural evidence for highly organized extravascular BL, unique to the SEL. The extravascular BL, termed fractones because of their fractal organization, were regularly arranged along the SEL and consisted of stems terminating in bulbs immediately underneath the ependyma. Fractones contacted local blood vessels by means of their stems. An individual fractone engulfed in its folds numerous processes of astrocytes, ependymocytes, microglial cells, and precursor cell types. The attachment site (base) of stems to blood vessels was extensively folded, overlying large perivascular macrophages that belong to a fibroblast/macrophage network coursing in the perivascular layer and through the meninges. In addition, collagen-1, which is associated with BL and growth factors during developmental morphogenetic inductions, was immunodetected in the SEL and particularly regionalized within fractones. Because macrophages and fibroblasts produce cytokines and growth factors that may concentrate in and exert their effect from the BL, we suggest that the structure described is implicated in adult neurogenesis, gliogenesis, and angiogenesis.  相似文献   
40.
The authors interviewed 41 mothers of young boys with fragile X syndrome to determine the process by which they learned their child had fragile X syndrome. The average family had concerns about the child's development at 9 months of age. Developmental delay was determined at an average age of 24 months, and fragile X syndrome was diagnosed at a mean age of 35 months. Considerable variability was found in age of first concern, determination of delay, and diagnosis of fragile X syndrome. Three child variables (severity of delay, autistic behavior, temperament style) and four family variables (mother's age, mother's education, sibling status, social support) did not account for this variability, although birth year did (children born more recently were somewhat more likely to be identified earlier). Families often encountered physicians who initially discounted concerns or said that it was too early to determine whether a problem did indeed exist. Given current knowledge and practice, improving the early identification (under 3 years of age) of children with fragile X syndrome is likely to remain difficult if based solely on behavioral and clinical observations.  相似文献   
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