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451.
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In the present study waste disposal patterns of 10 purposelyselected health care institutions from two states of India havebeen examined. Data were collected by pre-structured interviewsof hospital administrators and on-the-spot observations, andwere evaluated with reference to the possibility of transmissionof various diseases, including HIV infection. It was observedthat none of these institutions had a documented waste managementand disposal policy. All categories of waste were disposed bybeing thrown on the open ground or in open municipal cans withoutany pre-treatment, rendering them accessible to rag-pickers.Both the internal and external transportation of hospital wasteswere faulty and hazardous. A physical examination of 40 rag-pickersand 70 hospital workers who were directly involved in the disposalof hospital wastes, revealed that almost 40% (n= 47) of themsuffered from skin infections and/or had cuts or abrasions ontheir palms, hands, or feet. None of them ever ued hand gloveswhile working and only a limited few (n = 23) were found tobe wearing shoes while coming in contact with hospital wastes.This study stresses the importance of periodic in-service orientationprogrammes for all categories of health care personnel and suggestssome acceptable and affordable alternative measures for disposalof hospital wastes.  相似文献   
453.
Six patients with documented dissections of the thoracic aorta (two Type A, four Type B) were examined by magnetic resonance (MR) imaging using a 0.6-Tesla superconductive magnet. Cardiac gating was applied in five cases. Correlation was made with CT and angiography. MR imaging demonstrated the dissection in all six cases and accurately differentiated Type A from Type B dissections. Coronal and sagittal MR sections were advantageous in establishing the relationship of the three arch vessels to the dissection. In addition, cardiac-gated MR was useful in demonstrating mural thrombus and in distinguishing the true from the false lumen based on differences in signal intensity resulting from different flow rates. In five cases, the information obtained by MR was equal to or surpassed that obtained by CT. In the one case of a completely thrombosed dissection, the CT scan was more helpful. MR should become an important imaging modality in the evaluation of aortic dissections.  相似文献   
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可注射性磷酸钙骨水泥生物相容性评价   总被引:2,自引:0,他引:2  
目的:磷酸钙骨水泥是一种新型骨移植替代材料,对它的改性研究是近年来的研究热点之一,通过改变磷酸钙骨水泥的流变学,制备可注射性磷酸钙骨水泥更适于微创应用,但应用于临床要对其生物相容性进行评价。方法:实验于2006-10/2007-01在天津医院骨科研究所完成。①实验材料:可注射性磷酸钙骨水泥(由固相与液相两部分组成,固相为碳酸钙、磷酸氢钙等,液相为磷酸钠盐溶液)。②实验动物:新西兰兔14只,体质量2.0~3.5kg,雌雄各半。实验过程中对动物处置符合动物伦理学要求。③实验方法和评估:通过采用可注射性磷酸钙骨水泥浸提液和试件与骨髓基质细胞分别共培养,MTT法测定细胞相对增殖率,进行细胞毒性反应分级,光镜和扫描电镜观察细胞生长形态和生长活性。可注射性磷酸钙骨水泥浸提液进行溶血和热原试验观察。将可注射性磷酸钙骨水泥试件植入兔肌肉内,观察炎症反应和纤维包膜形成情况。结果:14只新西兰兔均进入结果分析。可注射性磷酸钙骨水泥浸提液和试件与骨髓基质细胞共培养,细胞生长形态良好,数量逐渐增加,细胞毒性反应为0~Ⅰ级,基本无毒性。浸提液的溶血率<0.05%,注入兔耳缘静脉后未引起发热反应。可注射性磷酸钙骨水泥试件植入兔肌肉中观察24周,早期有淋巴细胞浸润,包膜形成,晚期淋巴减少或消失,包膜稳定,无增厚趋势,未见有白细胞浸润。结论:可注射性磷酸钙骨水泥具有良好的生物相容性,符合植入人体生物材料的细胞毒性要求,对机体不会造成不良影响,因而临床可以安全使用。  相似文献   
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Wound healing in the adult is commonly compromised by excessive scar formation. In contrast, fetal wound healing is a regenerative process characterised by the conspicuous absence of scarring. Available evidence suggests that phenotypic differences between fetal and adult fibroblasts are important determinants of these distinct modes of tissue repair. In this context, a number of groups (including our own) have documented differences between fetal and adult fibroblasts with respect to such potentially relevant characteristics as migratory activity, motogenic response to cytokines and the synthesis of motility factors, cytokines and matrix macromolecules. The oral mucosa appears to be a privileged site in the adult in that it continues to display a fetal-like mode of wound healing. Data are presented in this review indicating that a subpopulation of gingival fibroblasts expresses several 'fetal-like' phenotypic characteristics. These observations are discussed in terms of both the continued expression of a fetal-like mode of wound healing in the oral mucosa and the possible differential involvement of distinct fibroblast subpopulations in the progression of periodontal disease.  相似文献   
459.
ObjectiveTo investigate the nutritional status of the males and females in two subgroups of the Bhotia tribe (Marcha and Tolcha) inhabiting in three different altitudes in Uttaranchal, India.MethodsData were collected from the Tolcha and Marcha, two sub-groups of the Bhotia, inhabiting in Chamoli district of Uttaranchal. Bhotia adults of both sexes were considered. Field investigation was conducted in three ecological zones (high, middle and low altitude) of the district during April-August, in the years 2002-2004. Anthropometric measurements were obtained in accordance with the techniques recommended by Weiner and Lourie (1981). The variables like height, weight, waist circumference, hip circumference, waist-hip ratio and blood pressure were studied in relation to BMI.ResultsRelatively higher value of mean BMI is recorded among the females than that of the males, which is true for different altitudes, in both subgroups. The BMI also indicates an inverse relationship with altitude, except for the Tolcha males in high altitude. Lowest mean BMI is recorded in middle altitude among the Tolcha subgroup. Chronic energy deficient (CED) individuals are much more than twice the number among the males of both the subgroups inhabiting in different altitudes. Interestingly, the percentage of CED individuals increases with the altitude.ConclusionsRegression analysis indicates that height, weight, hip circumference and waist circumference are dependent on body mass index in the studied populations. Probable reason for poor nutrition status among the Tolcha and Marcha of high altitude might be due to the fact that the Tolcha and Marcha of high altitude consume lesser amount of proteins, fat, milk and milk products in general than their counterpart inhabit in lower and middle altitude.  相似文献   
460.

Background and purpose:

There are interactions between endothelin-1 (ET-1) and endothelial vascular injury in hyperhomocysteinemia (HHcy), but the underlying mechanisms are poorly understood. Here we evaluated the effects of HHcy on the endothelin system in rat carotid arteries.

Experimental approach:

Vascular reactivity to ET-1 and ETA and ETB receptor antagonists was assessed in rings of carotid arteries from normal rats and those with HHcy. ETA and ETB receptor expression was assessed by mRNA (RT-PCR), immunohistochemistry and binding of [125I]-ET-1.

Key results:

HHcy enhanced ET-1-induced contractions of carotid rings with intact endothelium. Selective antagonism of ETA or ETB receptors produced concentration-dependent rightward displacements of ET-1 concentration response curves. Antagonism of ETA but not of ETB receptors abolished enhancement in HHcy tissues. ETA and ETB receptor gene expressions were not up-regulated. ETA receptor expression in the arterial media was higher in HHcy arteries. Contractions to big ET-1 served as indicators of endothelin-converting enzyme activity, which was decreased by HHcy, without reduction of ET-1 levels. ET-1-induced Rho-kinase activity, calcium release and influx were increased by HHcy. Pre-treatment with indomethacin reversed enhanced responses to ET-1 in HHcy tissues, which were reduced also by a thromboxane A2 receptor antagonist. Induced relaxation was reduced by BQ788, absent in endothelium-denuded arteries and was decreased in HHcy due to reduced bioavailability of NO.

Conclusions and implications:

Increased ETA receptor density plays a fundamental role in endothelial injury induced by HHcy. ET-1 activation of ETA receptors in HHcy changed the balance between endothelium-derived relaxing and contracting factors, favouring enhanced contractility.British Journal of Pharmacology (2009) 157, 568–580; doi:10.1111/j.1476-5381.2009.00165.x; published online 9 April 2009This article is part of a themed section on Endothelium in Pharmacology. For a list of all articles in this section see the end of this paper, or visit: http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009  相似文献   
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