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1.
The clinical, radiologic, and histopathologic findings of a case of bilateral dacryops is reported in a 49-year-old man. The patient presented with cystic masses located in superior lateral orbits and underwent bilateral excisions of these without any postoperative complications.  相似文献   
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Two cases of intracorneal hemorrhage developing as a complication of aphakic contact lens use are reported. Patient 1 had a penetrating keratoplasty to restore vision and therefore the histologic examination could be performed on the corneal button. In patient 2 the contact lens use was discontinued with partial resolution of the intracorneal hemorrhage and the patient then underwent a secondary intraocular lens implantation with good visual results.  相似文献   
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目的探讨西藏拉萨地区幽门螺杆菌(Helicobacter pyloric,Hp)感染与冠心病及多种危险因素的关系。为该地区冠心病的防治提供依据。方法分为冠心病组46例和非冠心病组51例,应用检测血抗HpIgG及-C-尿素呼气试验方法检测Hp感染情况,并分别测定各组血脂、血糖、餐后2h血糖、C反应蛋白、纤维蛋白原、白细胞总数。结果冠心病组患者血清抗HpIgG阳性率为50.0%(23/46),明显高于非冠心病组的23.5%(12/51),P〈0.05;冠心病患者Hp现症感染率为54.3%(25/46),明显高于非冠心病组的31.3%(27/51),P〈0.05;冠心病组Hp感染患者血脂、空腹及餐后2h血糖、C反应蛋白、纤维蛋白原较非感染患者明显升高(P〈0.05)。结论Hp感染与冠心病相关,可能是拉萨地区冠心病发病的独立危险因素。  相似文献   
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Retinal photoreceptor degeneration was induced by exposing albino rats to fluorescent illumination at elevated environmental temperatures. Fine carbon particles were injected intravenously or directly into the vitreous body or anterior chamber of the eye. The resulting pattern of invasion, migration, and egression of carbon-filled phagocytes in eyes with degenerated retinas was reconstructed from a time sequence series of light and electron microscopic tissue sections. Retinal debris, such as damaged photoreceptor outer segments and carbon particles, was most frequently removed by two populations of cells possessing phagocytic properties: mononuclear cells of vascular origin and pigment epithelial cells. After retinal damage, mononuclear cells appeared first in the vitreous body and later, in time sequence, progressively deeper in the inner plexiform layer and out to the bipolar nuclear layer, where they were seen within, or partially within, retinal capillaries. After intravenous carbon injection, however, marked phagocytes were not seen in the retina. Carbon-filled phagocytic cells were observed in the choroidal connective tissue and blood vessels after intravenous injection, but not after intravitreal injections of carbon. Therefore, retinal phagocytes did not appear to leave the eye through the choroidal circulation. Pigment epithelial cells proliferated by mitotic activity, occurred as single cells separated from Bruch's membrane, and were seen among the degenerated outer segments. After direct exposure to carbon particles, pigment cell phagosomes contained both carbon and lamellated discs of degenerated outer segments. Whether these cells exited from the eye through retinal capillaries or returned to Bruch's membrane to reestablish continuity in the pigment epithelium could not be determined.  相似文献   
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Hecht  SS; Ronai  ZA; Dolan  L; Desai  D; Amin  S 《Carcinogenesis》1998,19(1):157-160
We compared the tumor-initiating activities toward mouse skin of two structurally related polycyclic aromatic hydrocarbon diol epoxides: racemic anti-1,2,3,4-tetrahydro-5,6-dimethylchrysene-1,2-diol-3,4- epoxide (5,6-diMeCDE) and racemic anti-1,2,3,4-tetrahydro-5- methylchrysene-1,2-diol-3,4-epoxide (5-MeCDE). Tumors induced by these diol epoxides were analysed for mutations in the Ha-ras gene. 5,6- diMeCDE is derived from the non-planar parent compound 5,6- dimethylchrysene, and reacts to approximately equal extents with dA and dG in DNA, whereas 5-MeCDE is derived from a nearly planar parent compound, 5-methylchrysene, and reacts mainly with dG in DNA. 5,6- diMeCDE, at initiating doses of 33, 100 or 400 nmol per mouse, induced 1.2, 2.2 and 6.2 skin tumors per mouse, respectively. It was significantly less tumorigenic than 5-MeCDE which induced 3.1, 7.5 and 9.1 skin tumors per mouse at the same doses. Tumors induced by 5,6- diMeCDE had a large number of CAA-->CTA mutations in codon 61 of the Ha- ras gene: 50, 55 and 75% of the tumors analysed had this mutation at the 33, 100 and 400 nmol doses. No mutations were found in codons 12 and 13 in the tumors induced by 5,6-diMeCDE. In contrast, CAA-->CTA mutations in codon 61 were rarely seen in tumors induced by 5-MeCDE. At the highest dose of 5-MeCDE, 20% of the tumors analysed had mutations at G of codons 12 and 13. The results of this comparative study support the hypothesis that mutations in the Ha-ras gene in mouse skin tumors induced by PAH diol epoxides occur as a result of their direct reaction with the gene. However, pathways other than the commonly observed Ha- ras codon 61 mutations are clearly important in mouse skin tumorigenesis by these diol epoxides.   相似文献   
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Antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized by arterial and/ or venous thrombosis accompanied by persistently elevated levels of antiphospholipid antibodies (aPLs). The aim of this study is to evaluate the pulmonary manifestations of APS and compare the levels of aPLs in patients with and without pulmonary involvement. We retrospectively reviewed the files of patients with the diagnosis of APS between October 2010 and May 2017. Demographic data, clinical, radiological and laboratory findings were recorded. The study included 67 patients (56 female/11 male) with a mean age of 39?±?13 years. Pulmonary manifestations such as parenchymal and/or vascular involvement were seen in 12 (17.9%) patients. The patients with and without pulmonary manifestations were not significantly different in terms of age (p?=?0.46), comorbidities (p?=?0.48) and APS duration (p?=?0.66). Acute pulmonary thromboembolism (PE) was determined in 11 (16.4%), alveolar hemorrhage in 2 (3%) patients. Four patients with acute PE (36%) developed chronic thromboembolic pulmonary hypertension (CTEPH). One patient developed both CTEPH and diffuse alveolar hemorrhage after acute PE during follow up. Antiphosholipid antibody IgM was highly positive in patients with PE compared to patients without PE (p?=?0.005). Other antibodies and lupus anticoagulant were not significantly different in patients with and without PE. None of the patients were deceased due to pulmonary manifestations of APS. PE was the most common pulmonary manifestation of APS. The development of CTEPH was high among APS patients. Patients with APS should be closely followed for the onset of PE and CTEPH.

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