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101.
Corneal neovascularization   总被引:15,自引:0,他引:15  
Corneal neovascularization (NV) is a sight-threatening condition usually associated with inflammatory or infectious disorders of the ocular surface. It has been shown in the field of cancer angiogenesis research that a balance exists between angiogenic factors (such as fibroblast growth factor and vascular endothelial growth factor) and anti-angiogenic molecules (such as angiostatin, endostatin, or pigment epithelium derived factor) in the cornea. Several inflammatory, infectious, degenerative, and traumatic disorders are associated with corneal NV, in which the balance is tilted towards angiogenesis. The pathogenesis of corneal NV may be influenced by matrix metalloproteinases and other proteolytic enzymes. New medical and surgical treatments, including angiostatic steroids, nonsteroidal inflammatory agents, argon laser photocoagulation, and photodynamic therapy have been effective in animal models to inhibit corneal NV and transiently restore corneal "angiogenic privilege."  相似文献   
102.
BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification.  相似文献   
103.
The nuclear medicine bleeding scan is frequently insufficient to locate sites of bleeding precisely, in spite of its great sensitivity. A small, hand-held Geiger-Müller counter, placed directly on exposed intestine in the operating room, enables precise location of the probable bleeding site. In three patients, the technique allowed a minimal amount of intestine to be resected, distinguished between large- and small-intestinal hemorrhage, and eliminated other foci as sites of bleeding.  相似文献   
104.
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106.
AIMS: Long acting subcutaneous testosterone pellets are of proved efficacy for the treatment of hypogonadal men, but have not been reported as a treatment modality in adolescent boys. Pharmacodynamic studies of subcutaneous testosterone release have shown prolonged normalisation of testosterone levels for at least four months. Administration of a long acting, safe, effective, and convenient form of treatment is desirable when life-long treatment is indicated. PATIENTS AND METHODS: Eighteen boys (aged 13.9-17.5 years at the start of treatment)-seven with primary hypogonadism, nine with secondary hypogonadism, and two boys being treated with testosterone for tall stature--were given testosterone pellets (8-10 mg/kg) every six months for 18 months. Height, weight, pubertal status, and psychosocial parameters were assessed and follicle stimulating hormone, luteinising hormone, testosterone, prolactin, and lipids were measured at 0, 1, 3, 6, 12, and 18 months. Bone age was measured at 0 and 12 months. RESULTS: In all boys growth velocity continued appropriately for bone age. Puberty continued to progress in all boys and in two boys the amount of virilisation exceeded that seen with previous treatment with intramuscular testosterone. After testosterone administration, follicle stimulating hormone and luteinising hormone suppressed incompletely in the boys with primary hypogonadism. Serum testosterone ranged from 4.3 to 26.7 nmol/l at three months to less than 10 nmol/l at six months after implantation. Prolactin and lipid levels were normal throughout the study. By report, there was an improvement in mood and emotional wellbeing. No pellet extrusions occurred in a total of 156 pellet insertions. CONCLUSIONS: All boys preferred this mode of testosterone administration to intramuscular injections. Long acting subcutaneous testosterone pellets are safe, efficacious, well tolerated, and convenient, and result in normal physical growth and improved psychological outlook in adolescent hypogonadal boys.  相似文献   
107.
郑运松  徐会吾 《医学争鸣》2009,(21):2435-2437
目的:探讨Balo病同心圆硬化(BCS)的磁共振表现特征及其病理基础.方法:回顾性分析4例Balo病同心圆硬化患者的MRI表现,均经激素治疗临床症状好转后行MRI复查.结果:4例患者中,1例单发,3例多发,最多者病灶5个.病变主要累及大脑半球皮层下和深部白质区,共发现11个病灶,其中顶叶半卵圆中心和颞叶的发病比例高.典型同心圆样病灶8个,直径1~2.3cm,同心圆层数为3~5个.在T1WI加权像呈等、低信号相间;T2WI,FLAIR像上呈等、高信号交替环,病灶周围有轻度水肿表现,上述表现与镜下脱髓鞘区与髓鞘保留区相间相对应.其余3个不典型的病灶呈斑片状或煎蛋样改变;增强后1例病灶呈点状或边缘线状强化.结论:Balo病同心圆性硬化的MRI及其增强扫描具有特征性表现,可作为本病诊断的主要方法,并可用于疗效的观察.  相似文献   
108.
PURPOSE: To describe a simplified new technique for repositioning and attaching a suture to the haptic of a displaced posterior chamber intraocular lens (IOL). METHODS: We describe a double-knot technique for repositioning and transscleral suture fixation of a subluxed posterior chamber IOL after penetrating keratoplasty. Two 10-0 Prolene transscleral sutures on straight needles are passed around the IOL haptic, tied extraocularly, and used to secure the repositioned haptic of the IOL. A second knot ties the transscleral suture in the scleral bed, stabilizing the haptic in the ciliary sulcus. RESULTS: In the case described, the IOL was stable and well positioned 2 months after surgery. CONCLUSION: The double-knot technique for intraocular repositioning and transscleral suture fixation of displaced posterior chamber IOLs reduces the extensive intraocular manipulation and scleral incisions required for IOL exchange and may reduce chronic irritation associated with iris fixation.  相似文献   
109.
The effect of barium on blood in the gastrointestinal tract   总被引:2,自引:0,他引:2  
  相似文献   
110.
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