2,518 research outputs found

    A stereological study of the effects of mercury inhalation on the cerebellum

    Get PDF
    Mercury in the environment that arises from organic and inorganic sources can cause irreversible damage to the nervous system. Toxicity may be direct or may arise from interactions with other metals in the environment. We evaluated the possible effects of mercury vapor on rat cerebellum. Twelve adult female rats were divided into control and experimental groups. The rats in the experimental group were exposed to mercury vapor for 9 h/day for 45 days. Cerebellar tissue samples were evaluated using stereology and for histopathology. The total number of Purkinje cells was estimated using a physical disector method. We found that in the experimental group, overall volume decreased and the number of Purkinje cells was reduced. We also found cellular damage including pycnotic nuclei, eosinophilic cytoplasm and vacuolization; these features were absent in the control group. We found that chronic exposure to inorganic mercury vapor is toxic to the cerebellum

    Comparative cone-beam computed tomography evaluation of the osseous morphology of the temporomandibular joint in temporomandibular dysfunction patients and asymptomatic individuals

    Get PDF
    We examined the bone components of the temporomandibular joint (TMJ) in asymptomatic individuals and patients with temporomandibular dysfunction (TMD) using cone-beam computed tomography (CBCT). Two hundred asymptomatic individuals and 200 patients with TMD were included in this study. Condyle position, eminence height, eminence inclination, condyle shape, and fossa shape were assessed on CBCT images of the 800 temporomandibular joints. The eminence inclination (P < 0.05), eminence height (P < 0.0001), mediolateral width of condyle (P < 0.0001), and anterior joint space (P < 0.0001) were significantly greater in male subjects compared with female subjects in both the asymptomatic group and TMD group. Comparisons of the asymptomatic group and TMD group revealed significant differences in the anterior joint space (P < 0.0001), ratio of anterior joint space to posterior joint space (P < 0.001), posterior joint space (P < 0.05), eminence inclination (P < 0.05), eminence height (P < 0.05), condyle shape (P < 0.0001), and fossa shape (P < 0.05). The present analyses suggest that a steeper articular eminence inclination may be risk factor for TMD. The presence of TMD was associated with the condyle position in the TMJ

    International Capital Mobility and Factor Reallocation in a Multisector Economy

    Get PDF
    This paper examines the effects of international capital flows in a small open econ omy utilizing a dynamic general equilibrium framework based on a three-sector Ramsey growth model. In order to analyze the impact of international capital mobility on production, consumption and allocation of resources across three sectors ,two different economic environments are modelled. The first model represents an open economy with capital mobility (a more comprehensive environment),and the second model introduces a closed economy with no capital mobility. Numerical applications of the models use data from the Turkish economy for the year 2002. The numerical results demonstrate that the presence of capital mobility, despite being limited by a borrowing constraint, reverses the impact of economic growth on production and resource allocation. The results also show that while production in the closed economy model simply adjusts to domestic demand, that of the open economy model is not constrained by it. Results further point that although there is positive growth in income and output in both environments, income growth in the capital mobility environment falls short of that in the no capital mobility environment. This result can be attributed to the relatively slower accumulation of capi tal in the former, which may be compensated by a positive rate of technological progress to accompany international capital flows.International Capital Flows,Human Capital, Multisector economy,Borrowing Constraint

    Inhalation of mercury vapor can cause the toxic effects on rat kidney

    Get PDF
    Dental amalgam has been used in dentistry as a filling material. The filler comprises mercury (Hg). It is considered one of the most important and widespread environmental pollutants, which poses a serious potential threat for the humans and animals. However, mercury deposition affects the nervous, cardiovascular, pulmonary, gastrointestinal, and especially renal systems. In most animals' species and humans, the kidney is one of the main sites of deposition of mercury and target organ for its toxicity. In this study, the effects of mercury intake on kidney in rats were searched. For the this purpose; we used 24 adult female Wistar albino rats (200g in weight) obtained from Experimental Research and Application Center of Ataturk University with ethical approval. Besides, they were placed into a specially designed glass cage. Along this experiment for 45 days, subjects were exposed to (1mg/m(3)/day) mercury vapor. However, no application was used for the control subjects. At the end of the experiment, kidney samples were obtained from all subjects and processed for routine light microscopic level and stereological aspect were assessed. Finally, according to our results, mercury affects the histological features of the kidney. That means, the severe effects of mercury has been shown using stereological approach, which is one of the ideal quantitative methods in the current literature. In this study, it was detected that chronic exposure to mercury vapor may lead to renal damage and diseases in an experimental rat model

    Effect of mercury vapor inhalation on rat ovary: stereology and histopathology

    Get PDF
    AimMercury, an environmental contaminant, is a risk factor for health in whole living organisms. In this study, we investigated whether mercury vapor (HgO) inhalation has an effect on rat ovary. MethodsTwelve Wistar albino rats were divided equally into experimental (Hg) and control groups (n = 6). Animals in the Hg group were exposed to HgO for 45 days at a dose 1 mg/m(3)/day, after which, histological and stereological assessment were carried out. ResultsOvaries exposed to HgO had histo-morphometric alterations. HgO inhalation resulted in reduction of the total number of primordial, primary and Graaf follicles. Also, mean volume of ovary, medulla and cortex, corpus luteum (c.luteum) and Graaf follicles was decreased in the Hg group. Moreover, there was a significant increase in total volume of the atretic follicles. On light microscopy, thickening of tunica albuginea, increase of fibrils within the connective tissue, congestion of the capillaries and venous vessels, thinned walls and fibrin deposition in some large blood vessels, and edema were seen. Also, irregular follicle and oocyte borders, and hydropic degeneration in follicular granulosa cells were detected. ConclusionStructural alterations could be attributed to the toxic influence of HgO on rat ovary. The use of Hg should therefore be more controlled to minimize its toxic effect

    Ectopic premolar tooth in the sigmoid notch

    Get PDF
    Impaction of a mandibular premolar is relatively uncommon. Ectopic placement is more unusual and there has been no discussion in the literature of an ectopic mandibular premolar in the coronoid process. In this case report, we present an impacted ectopic mandibular permanent premolar in the sigmoid notch (incisura mandibulae) region. Etiology of the tooth and treatment options are discussed and illustrated by Cone Beam Computed Tomography (CBCT) images

    God and World in the Ontology of al-Ghazali

    Get PDF
    The purpose of this article is to reveal al-Ghazali's understanding of God and world on the ontological basis. He bases the purpose of existence of the world with to know God. In such a study, it is difficult to distinguish ontology from epistemology. Al-Ghazali classifies beings in different perspectives. However, all beings consist of the God and acts of God. God is a unique entity, which is compulsory, source of existence and sacred. His adjectives are with him. God is completely different from what he created. Creatures cannot fully grasp it. God is not far from the world, but he is very close to his servants. The world is everything outside of God and his attributes. All beings are acts of God. The world owes its existence and continuation to God. The world that is the act of the God actually introduces us to the God. The purpose of the creation of the world is to introduce God
    corecore