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101.
The molecular distribution of insulin-like growth factor I (IGF-I) and IGF-II among the IGF binding proteins (IGFBPs) was studied before and during IGF-I therapy in Ecuadorean adults with growth hormone receptor deficiency (GHRD). Of the total circulating IGF-I and IGF-II, 70% was carried by the 150 kDa complex in normal subjects, while in patients with GHRD, 50% of serum IGF-I, but only 30–35% of serum IGF-II, was measured within the 150 kDa IGFBP-3 region. Administration of IGF-I altered the concentration of IGF-I and IGF-II, although the percentage of total IGF measured within each IGFBP region was not affected, as the increase in IGF-I and the decrease in IGF-II were proportional. Similarly, serum concentrations of IGFBP-3 and the acid-labile subunit, measured by radioimmunoassay, were unaltered. Thus, administration of IGF-I to patients with GHRD was unable to correct the aberrant distribution of IGFs among the IGFBPs.  相似文献   
102.
PURPOSE: To describe two children who developed anterior uveitis after vaccination for common childhood diseases. METHODS: A retrospective study of two Saudi patients who were seen at The Eye Center, Riyadh, Saudi Arabia. RESULTS: Aged 12 and 14, respectively, the two patients developed anterior non-granulomatous uveitis 6 and 4 weeks after having the combined vaccination for measles, mumps and rubella (MMR). No other definite cause of uveitis was detected from history or from laboratory work up. Both patients responded to traditional regimens of uveitis therapy. However, they required a treatment period of several months. CONCLUSION: Anterior uveitis may occur following MMR vaccination. Cases of vaccination thus require ophthalmic awareness if visual symptoms or a painful red eye develop.  相似文献   
103.
Sj?gren syndrome is a chronic systemic disease characterized by polyglandular tissue destruction leading to keratoconjunctivitis sicca (KCS) and xerostomia. Patients with primary Sj?gren syndrome show evidence of KCS and xerostomia, whereas patients with secondary Sj?gren syndrome suffer from KCS, xerostomia, and an autoimmune disease, most commonly rheumatoid arthritis. Certain factors cause autoimmune dysregulation leading to destruction of the acinar cells and ductal epithelia with subsequent dry eyes and dry mouth. Activated lymphocytes in patients with autoimmune diseases appear to have selective homing into the lacrimal and salivary glands leading to tissue damage. Understanding the factors involved in the immune dysregulation may improve our diagnostic and therapeutic approaches in Sj?gren syndrome. Current therapeutic measures include means to increase secretion, relieve symptoms, and repair damage of the ocular surface.  相似文献   
104.
PURPOSE: To study the processes involved in mediating conjunctival remodelling in vernal keratoconjunctivitis (VKC) by investigating the expression of integrin receptors, epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), transforming growth factor-beta(TGF-beta), basic fibroblast growth factor (bFGF), platelet-derived growth factor (PDGF), and Ki67 antigen, which is a marker for cell proliferation. METHODS: Conjunctival biopsy specimens from 16 patients with active VKC and nine control subjects were studied by immunohistochemical techniques using monoclonal and polyclonal antibodies directed against the integrin alpha3 and alpha6 subunits, EGFR, VEGF, TGF-beta, bFGF, PDGF, and Ki67 antigen. The phenotype of inflammatory cells expressing growth factors was examined by double immunohistochemistry. RESULTS: In the normal conjunctiva, very weak immunoreactivity was observed for EGFR and VEGF in epithelial cells, and for alpha3 and alpha6 integrin subunits on basal epithelial cells, and on vascular endothelial cells in the upper substantia propria. There was no immunoreactivity for the other antibodies. In VKC specimens, strong staining for alpha3 and alpha6 integrin subunits was observed on the membranes of basal and suprabasal epithelial cells, and all vascular endothelial cells. Immunoreactivity for Ki67 antigen was observed in the nuclei of the basal and suprabasal epithelial cells. Strong immunoreactivity was observed for EGFR in the deeper layers of the epithelium, and for VEGF in all epithelial cells. Inflammatory cells expressing EGFR, VEGF, TGF-beta, bFGF, and PDGF were noted in 8, 9, 11, 10, and 10 specimens, respectively. The majority of inflammatory cells expressing growth factors were eosinophils (45+/-4%) and monocytes/macrophages (35+/-4%). CONCLUSIONS: Chronic conjunctival inflammation in VKC is associated with increased staining of alpha3, and alpha6 integrin subunits, EGFR, VEGF, TGF-beta, bFGF, and PDGF that might mediate conjunctival remodelling.  相似文献   
105.
PURPOSE: To present a case of ligneous conjunctivitis where the recurrence of membranous conjunctivitis was prevented by subconjunctival and topical instillation of fresh frozen plasma. DESIGN: Interventional case report. METHODS: A case of ligneous conjunctivitis with multiple recurrences since the age of 3 years developed recurrent membranous conjunctivitis after transconjunctival levator recession. Blood plasminogen activity was determined. The membrane was excised, and the membrane reappeared 4 days later. The patient was treated with excision of the membrane and subconjunctival injection of fresh frozen plasma and topical fresh frozen plasma. Plasminogen activity of the fresh frozen plasma was normal. RESULTS: Plasminogen blood functional activity was 52% (normal is 80%-120%). The patient had complete remission with no recurrences of membranous conjunctivitis after topical and subconjunctival fresh frozen plasma. CONCLUSIONS: Prophylactic use of topical and subconjunctival fresh frozen plasma may help in the prevention of membranes in susceptible patients with plasminogen deficiency.  相似文献   
106.
107.
The inoculation of live, nonattenuated Leishmania major to produce a lesion in a selected site that heals, referred to as leishmanization, is to date the only vaccine against leishmaniasis that has proven to be effective in humans. Its use has been restricted or abandoned entirely, however, due to safety concerns. In an attempt to develop a leishmanization protocol that minimizes pathology while maintaining long-term protection, live parasites were coinjected with CpG-containing immunostimulatory oligodeoxynucleotides (CpG ODNs) alone or in combination with whole-cell lysates of heat-killed L. major promastigotes bound to alum (ALM). C57BL/6 mice infected intradermally by using L. major plus CpG ODN with or without ALM developed few or no dermal lesions and showed an early containment of parasite growth, while mice infected with L. major with or without ALM developed sizable dermal lesions that required up to 10 weeks to heal. The CpG ODNs provoked a transient inflammation that included an early recruitment and accumulation of gamma interferon-producing CD4(+) lymphocytes in the site. Attenuation of the live vaccine did not compromise its ability to confer long-term immunity, as mice receiving L. major and CpG ODN plus ALM were totally protected against reinfection with L. major for up to 6 months. By comparison, the immunity elicited by two efficient nonlive vaccines began to wane by 6 months. Our results suggest that immune modulation using CpG ODNs might be a practical approach to improving the safety of a highly effective live vaccine that has already been widely applied.  相似文献   
108.
BACKGROUND: To compare the incidence and severity of corneal haze after photorefractive keratectomy (PRK) among white patients with blue eyes and Saudi patients with brown eyes. DESIGN: Retrospective, nonrandomized, comparative trial. PARTICIPANTS: A total of 150 patients (71 females and 79 males) were included in this study. Two hundred sixty-six eyes of 150 patients were subjected to PRK. One hundred blue eyes of 50 white patients and 166 brown eyes of 100 Saudi patients were included in this study. METHODS: Two hundred sixty-six eyes of 150 patients were subjected to PRK with the Chiron Technolas Keracor 117C for the correction of myopia and astigmatism. MAIN OUTCOME MEASURES: All patients had complete ophthalmologic examinations, visual acuity testing, intraocular pressure, pachymetry, corneal haze assessment (0-4+), and computerized corneal topography. RESULTS: There were 266 eyes of 150 patients with 100 blue irides and 166 brown irides. The spherical equivalent was -0.50 diopter (D) to -8.75 D. The mean postoperative spherical equivalent at 6 months was -0.063 D (standard deviation [SD], +/-0.595) in blue eyes compared to -0.28 D (SD, +/-0.683) in brown eyes (P = 0.006). Ninety-five (95%) of 100 of the blue eyes achieved +/- 1 D of attempted correction compared to 148 (89.2%) of the 166 brown eyes. All patients with blue eyes had a visual acuity of 20/30 or better compared to 153 (92.2%) of the 166 brown eyes (P = 0.009). Forty-eight (18.04%) eyes had minimal to mild haze, 3 (1.12%) eyes had moderate haze, and 2 (0.75%) eyes had severe haze. The incidence of corneal haze among brown eyes was 48 (28.9%) of 166 eyes compared to 5 (5%) of 100 in blue eyes (P < 0.001). The difference remained significant after adjustment for age and gender with a P value of 0.0283. The relative risk for developing haze in brown eyes was found to be 7.72. CONCLUSION: The incidence of corneal haze after PRK was significantly higher among Saudi patients with brown irides than among white patients with blue irides. This suggests that racial factors may play a role in the development of corneal haze.  相似文献   
109.
Abstract: A preterm infant developed bilateral tension pneumothoraces and extensive vascular air embolism 6 h after being commenced on nasal continuous positive airway pressure (CPAP). Neonatal clinicians should be aware that catastrophic vascular air embolism could occur in infants receiving nasal CPAP, a modality of respiratory support conventionally considered non-invasive and 'safe'.  相似文献   
110.
Data from healthy children are needed to evaluate bone mineralisation during childhood. Whole body bone mineral content (BMC) and bone area were examined by dual energy x ray absorptiometry (Hologic 1000/W) in healthy girls (n = 201) and boys (n = 142) aged 5-19 years. Centile curves for bone area for age, BMC for age, bone area for height, and BMC for bone area were constructed using the LMS method. Bone mineral density calculated as BMC/bone area is not useful in children as it is significantly influenced by bone size. Instead, it is proposed that bone mineralisation is assessed in three steps: height for age, bone area for height, and BMC for bone area. These three steps correspond to three different causes of reduced bone mass: short bones, narrow bones, and light bones.  相似文献   
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