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Giant cell arteritis is a chronic granulomatous inflammation of unknown aetiology involving large and medium size arteries in the elderly. It causes acute visual loss from ischaemia to the optic nerves or central retinal artery occlusion. This is a rare cause of anterior ischaemic optic neuropathy in our local population. We present a patient who had bilateral loss of vision from sequential arteritic ischaemic optic neuropathy. She was treated with intravenous steroids immediately. Diagnosis was based on histopathological studies of temporal artery biopsies.  相似文献   
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OBJECTIVE: To assess the efficacy of a longer acting preparation of the gonadotrophin releasing hormone (GnRH) analogue goserelin (Zoladex LA, 10.8 mg) in 12 girls with central precocious or early puberty. METHODS: Two girls started treatment de novo; the remainder had been on suppressive treatment for a median duration of 1.5 (range, 0.2-5.6) years. Assessment comprising auxology, pubertal staging, and pelvic ultrasound examination was carried out at weeks 0, 4, 8, 10, and 12 (first cycle) and weeks 8, 10, and 12 (second cycle) to evaluate the required injection frequency. Thereafter, assessment was performed on the day of injection. Zoladex LA was given every 12 weeks unless pubertal progression occurred. RESULTS: Satisfactory control was achieved in eight patients using this regimen, and three patients required more frequent injections. One girl was removed from the study because of clinical progression and extreme mood swings. No serious adverse effects occurred. Mean height velocity during the study period was 4.5 cm/year (range, 3.1-6.6) compared with 6.5 cm/year (range, 3.8-9.6) before treatment in nine patients for whom data were available. CONCLUSIONS: Zoladex LA was effective in controlling precocious puberty in girls when given at intervals of 9-12 weeks and it is recommended that an initial assessment is made eight weeks after beginning treatment.  相似文献   
65.
The beta2 integrin (CD 18/CD 11 a, b, c) family of proteins mediate adherence of leukocytes to vascular endothelium and the associated ligand, intercellular adhesion molecule-1 (ICAM-1; CD 54), interacts with beta2 integrin proteins to allow transendothelial migration of leukocytes into sites of inflammation. The present study examines the function of these proteins in a murine model of acute cutaneous inflammation induced following topical application of 12-O- tetradecanoylphorbol-13-acetate (TPA) to the dorsal epidermis of SENCAR mice and in a model of skin multistage carcinogenesis. At 24 h following topical application of TPA to the dorsal epidermis of mice, dermal leukocytes expressed higher levels of beta2 integrin protein compared with the lower levels of beta2 integrin protein expression by peripheral blood leukocytes. ICAM-1 protein was localized to epidermal keratinocytes and vascular endothelium in TPA-treated skin and to proliferating papilloma cells. Intravenous (i.v.) injection of either 50 microg anti-beta2 integrin antibody alone or in combination with anti-ICAM-1 antibody significantly inhibited both TPA-stimulated neutrophil infiltration into the dermis (P < 0.001) and myeloperoxidase (MPO) activity (P < 0.03 anti-beta2 integrin antibody; P < 0.01 anti- beta2 integrin + ICAM-1 adhesion molecule antibodies), but had no effect on TPA-induced epidermal hyperplasia. In addition, injection of either anti-ICAM-1 adhesion molecule antibody alone (P < 0.004) or in combination with anti-beta2 integrin antibody (P < 0.001) significantly inhibited TPA-induced production of 7,8-dihydroxy-2'-deoxyguanosine (8- OHdG) immunoreactive proteins by epidermal keratinocytes. Beta2 integrin/ICAM-1 adhesion molecules work in concert to regulate migration, retention and functional activation of leukocytes within the dermis during TPA-induced skin inflammation and within stromal tissue of papillomas that form during multi-stage carcinogenesis. Agents that inhibit these receptor/ligand interactions may be useful in defining the roles of specific cell populations in cutaneous inflammation and multistage carcinogenesis and may also have potential as anti-promoting and anti-progression agents.   相似文献   
66.
Inactivation of the p53 tumor suppressor gene has been implicated in the pathogenesis of numerous human cancers, including osteosarcomas. Appendicular osteosarcomas of the dog appear to be a good model for their human equivalent with regard to biologic behavior, epidemiology and histopathology. We individually screened exons 5-8 of the p53 gene for mutations in 15 canine appendicular osteosarcomas using 'Cold' SSCP to compare the role of this gene in human and canine osteosarcoma tumorigenesis. Seven of the tumors (47%) exhibited point mutations, with one tumor possessing two mutations within different exons. Of these, seven were missense mutations and the eighth was a 'silent' mutation potentially affecting the exon 6-7 splicing region. Five of the missense mutations were located in highly conserved regions IV and V, while another corresponded with the highly conserved codon 220 mutational hotspot located outside the conserved domains. The locations and types of mutations were nearly identical to those reported in human cancer. These findings provide strong evidence of the involvement of p53 mutations in the development of canine appendicular osteosarcomas. Canine osteosarcomas appear to be a promising model for their human equivalent on a clinical, pathologic, and molecular level.   相似文献   
67.
One hundred patients of Diabetes Mellitus (70 with and 30 without clinical somatic neuropathy) were studied to correlate clinical severity with the magnitude of nerve conduction abnormalities. Age range was 10-79 years (mean 49) with equal number of males and females. Incidence of neuropathy was more in patients over 40 years of age (60 out of 70 patients) with duration of disease over two years (78.33%). The grades of severity were mild in 22 (31.33%), moderate in 25 (35.71%) and severe in 23 (32.86%) patients. Nerve conduction studies were carried out in 48 (27 with and 21 without clinical neuropathy) patients, using the apparatus Dantec (Cantata TM). The nerves (median, peroneal and sural) were stimulated at two points and the recording of latency; amplitude (micro V) and motor and sensory nerve conduction velocities (m/s) were done under identical environmental conditions. Sensory nerve conduction velocity was more affected than motor velocity. In the 21 patients without clinical neuropathy, 14 showed abnormalities indicating early involvement of peripheral nerves. Reduction of motor nerve conduction velocity was more in patients with moderate and severe grades. The reduction was more in lower than in upper limbs. Nerve conduction abnormality helps in diagnosis in diabetic neuropathy even in preclinical state and correlates with severity, in clinical neuropathy.KEY WORDS: Diabetic neuropathy, Nerve conduction abnormality, Peripheral neuropathy  相似文献   
68.
BACKGROUND: Children with neurodevelopmental disorders can have feeding problems. Malnutrition and recurrent aspiration pneumonia can increase the risk of morbidity and mortality. Video-fluoroscopic study of swallowing (VFSS) is essential in understanding the pathological mechanisms involved during swallowing. METHODS: The aim of the present study was to assess the role of VFSS in assessment and management of four children with various neurodevelopmental disorders in a multidisciplinary feeding team. We describe the team approach, with the participation of child neurologist, radiologist with the rehabilitation team including the speech therapist, occupational therapist and dietician, in the assessment and plan of management. RESULTS: Video-fluoroscopic study of swallowing had been useful in assessing the type of swallowing problems with treatment goals targeted to the basic underlying pathophysiological mechanism. CONCLUSION: A child neurologist should be involved in the multidisciplinary oromotor rehabilitation program for neurologically impaired children with feeding problems.  相似文献   
69.
OBJECTIVE AND BACKGROUND: It is generally accepted that cigarette smoke is a major risk factor for middle ear disease. However, the literature is void of articles addressing the direct relationship between cigarette smoke exposure and middle ear disease. Furthermore, there are many conflicting opinions concerning the role of cigarette smoke in the pathogenesis of middle ear disease. The purpose of this study was to evaluate the effects of cigarette smoke on the Eustachian tube mucosa. MATERIALS AND METHODS: Thirty healthy 150 to 230 g Sprague Dawley rats with normal middle ears were used. The animals were divided into six groups of five. Five experimental groups (N=5 each) were exposed to a domestic cigarette (This, tar 7.0 mg, nicotine 0.75 mg) every 30 minutes (total 2.5 hours, 5 cigarettes total) on a daily basis in a smoking chamber for 1, 2, 4, 6, or 8 weeks. A control group (N=5) was placed in the same chamber without exposure to cigarette smoke. After exposure, the animals were sacrificed and cross sections of the Eustachian tubes were prepared. Histologic changes of the Eustachian tube mucosa were observed through light and electron microscopes. RESULTS: Loss of cilia, goblet cell depletion, and squamous metaplasia of the Eustachian tube mucosa were observed following exposure to smoke. The one- and two-week exposure groups demonstrated the greatest decrease in goblet cell counts. The eight-week exposure group showed recovery from this decrease. Squamous metaplasia was observed in all experimental groups and was most prominent in the eight-week exposure group. CONCLUSION: These findings suggest that cigarette smoke directly affects Eustachian tube mucosa in the early stages of exposure. Some of the mucosal changes, however, were reversed during the latter stages of exposure. A mechanism different from that which occurs in the nasal cavity and trachea may be activated in the Eustachian tube after exposure to passive smoke. The protective function of the Eustachian tube may play some role in this mechanism.  相似文献   
70.
BACKGROUND: Open thoracic sympathectomy has been the established option for patients with essential hyperhidrosis. Recently, video-assisted endoscopic sympathectomy has provided a simple, safe, reliable, and cost-effective alternative to the earlier technique. With advances in instrumentation, performing the procedure through 2-mm and 3-mm needlescopic ports is now possible. The authors evaluate the effectiveness of so-called needlescopic thoracic sympathectomy for the treatment of primary hyperhidrosis. METHODS: Thirty five consecutive patients with a mean age of 24 years, including 23 men and 12 women, underwent bilateral needlescopic thoracic sympathectomies at the National University Hospital of Singapore. RESULTS: The mean operative duration was 56 minutes, and the mean hospital stay was 1.2 days. In no patient did Horner's syndrome or significant pneumothorax develop. The rate of success, defined as completely dry hands, was 97%. Two patients had unilateral recurrences that responded well to repeat needlescopic sympathectomies. We performed a total of 72 sympathectomies. CONCLUSIONS: Our study demonstrates that the use of miniature port access sites produces excellent medical and cosmetic results and is associated with a short hospital stay and low risk of complications.  相似文献   
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