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991.
992.
Two autopsy cases of female newborns with numerous morphologic and metabolic abnormalities were reported. These were considered Identical with a disorder which has been called leprechaunism or Donohue's syndrome, and were believed to be the first and second autopsy cases reported in this country. Although it has been presumed that these might be abnormalities of endocrine system or of metabolism, the authors could not find any factors which caused the disorder in spite of minute analysis of steroid hormones In urine, investigation of laboratory data as well as autopsy findings.  相似文献   
993.
994.
995.
Ultrastructure of the Human Complement Component, Clq   总被引:9,自引:5,他引:4       下载免费PDF全文
The human complement component, Clq, is a fragile molecule of delicate structure consisting of three distinct parts, a central subunit, connecting strands, and terminal subunits. Each terminal subunit is further subdivided into a large and a small subunit, and the central subunit appears to be divided into two equal parts. In the intact molecule, six connecting strands link six terminal subunits by their larger subdivision to the central subunit. The overall diameter of the molecule when viewed from the "top" is about 35 nm (350 A).  相似文献   
996.
Brief ischemia was reported to protect retinal cells against injury induced by subsequent ischemia-reperfusion with de novo protein synthesis, and this phenomenon is known as late ischemic preconditioning. The aims of the present study were to determine whether nitric oxide synthase (NOS) was involved in the mechanism of late ischemic preconditioning in rat retina using pharmacological tools. Under anesthesia with pentobarbital sodium, male Sprague-Dawley rats were subjected to 60 min of retinal ischemia by raising intraocular pressure to 130 mm Hg. Ischemic preconditioning was achieved by applying 5 min of ischemia 24 hrs before 60 min of ischemia. Retinal sections sliced into 5 microm thick were examined 7 days after ischemia. Additional groups of rats received NG-nitro-L-arginine and NG-monomethyl-L-arginin, non-selective NO synthase inhibitors, 7-nitroindazole, a neuronal NOS inhibitor, and aminoguanidine and L-N6-(1-iminoethyl) lysine, inducible NO synthase (iNOS) inhibitors before preconditioning, and were subjected to 60 min of ischemia. In the non-preconditioned group, cell loss in the ganglion cell layer and thinning of the inner plexiform and inner nuclear layer were observed 7 days after 60 min of ischemia. Ischemic preconditioning for 5 min completely protected against the histological damage induced by 60 min of ischemia applied 24 hrs thereafter. Treatment of rats with aminoguanidine and L-N6-(1-iminoethyl) lysine, but not NG-nitro-L-arginine, NG-monomethyl-L-arginine or 7-nitroindazole, wiped off the protective effect of ischemic preconditioning. The inhibitory effect of aminoguanidine was abolished by L-arginine, but not D-arginine. The results in the present study suggest that NO synthesized by iNOS is involved in the histological protection by late ischemic preconditioning in rat retina.  相似文献   
997.
The ocular microenvironment is immunosuppressive and anti-inflammatory. Pigment epithelial (PE) cells isolated from the eye possess a new property of suppressing T cell receptor-dependent activation of T cells in vitro. This property depends on their capacity to produce cell-surface and soluble inhibitory molecules. The iris pigment epithelia (IPE) do so through direct cell-to-cell contact with na?ve T cells, and this suppressive contact is mediated by interactions between B7 and membrane-bound TGFbeta that are expressed constitutively on IPE. We have now examined whether other ocular PE cells, e.g., retinal pigment epithelia (RPE) and ciliary body pigment epithelia (CBPE), have a similar suppressive property by a similar process. We have found that RPE and CBPE significantly suppress the activation of bystander T cells via soluble inhibitory factors. RPE and CBPE secrete different soluble inhibitory factors including TGFbeta1 and TGFbeta2. Although IPE cells suppress the activation of bystander T cells by membrane-bound TGFbeta, the RPE and CBPE do so by soluble forms of active TGFbeta through mechanisms independent of cell contact. These ocular PE cells are capable modifying T cell function by enhancing production of regulatory cytokines including TGFbeta. We propose that this mechanism of suppression via TGFbeta ensures that soluble active TGFbeta is released into the ocular microenvironment in order to create the immune privilege of the posterior segment of the eye.  相似文献   
998.
PURPOSE: To report a patient with Vogt-Koyanagi-Harada disease who developed neovascularization at the optic disc. CASE: A 19-year-old woman visited our hospital two months after becoming aware of fever, headache, tinnitus, hearing disturbance, and floaters in the right eye. Ophthalmic examination disclosed granulomatous inflammation in the anterior segment, sunset glow fundus and neovascularization at the optic disc. Vogt-Koyanagi-Harada disease was diagnosed and treated with corticosteroid pulse therapy, followed by oral corticosteroids. Three months after the systemic corticosteroid therapy, the neovascularization disappeared. CONCLUSIONS: Sufficient treatment with systemic corticosteroids is effective for the intraocular neovascularization associated with consecutive inflammation.  相似文献   
999.
1000.
PURPOSE: Three cases of corneal melting caused by a new nonsteroidal anti-inflammatory drug (NSAID), bromfenac sodium, are reported. CASE REPORTS: Case 1: A 58-year-old man with a history of bullous keratopathy caused by Fuchs' corneal dystrophy was treated for episcleritis with topical bromfenac sodium. After 15 days of treatment, melting (80% depth) was observed inferiorly in the paracentral cornea. Case 2: A 71-year-old man underwent uncomplicated pterygium surgery, followed by treatment with topical bromfenac sodium. After 40 days of treatment, a 60%-depth corneal melt occurred in the nasal limbus. Case 3: A 76-year-old woman had a suspected bacterial corneal ulcer that resolved with topical ofloxacin; however, after 5 days of treatment with topical bromfenac sodium, a perforation occurred in the inferonasal cornea. RESULTS: In all three cases, severe corneal melting was characterized by mild hyperemia, very faint infiltration, and mild pain. Conservative treatment, including the use of a bandage soft contact lens and/or antibiotics and lubrication, led to resolution in all cases. CONCLUSIONS: A new NSAID, bromfenac sodium, can lead to severe corneal melting. These findings, together with similar previous reports concerning diclofenac sodium and ketorolac, suggest that careful observation is required when using topical NSAIDs in the treatment of corneal disease.  相似文献   
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