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71.
Purpose: Pulsed holmium lasers are currently used to correct hyperopia by means of laser thermokeratoplasty (LTK). Series of μs laser pulses are applied with a high repetition rate to induce shrinkage of corneal collagen fibers. The pulsed energy application results in intrastromal temperature peaks of up to 200 °C. A continuously emitting laser diode can – as we demonstrated recently in an invivo study on minipigs – be used for LTK and may be of advantage because the temperature rise is more steady. The aim of this study was to examine the safety, amount, and stability of hyperopic correction of diode LTK on blind human eyes. Methods: We used a laserdiode that was set to continuously emit light at λ = 1.854 μm/μa = 1.04 mm–1(group I, n = 4) or 1.87 μm/μa = 1.92 mm–1 (group II, n = 4). Radiation energy was 100 to 150 mW for 10 s per coagulation. Eight coagulations on a single ring (group I) and 16 coagulations on a double ring (group II) diameter were applied in the cornea concentric to the entrance pupil by means of a vacuum-fixed application mask (group I = conjunctival fixation; group II = corneal fixation) and a handpiece with a focusing optic. Preoperatively as well as 1 week, 1, 2, 3, 6 12 and 18 months postoperative ophthalmologic controls were performed and the corneal refractive power was measured. Results: In group I initial refractive changes of up to + 4.9 D were achieved (1 week postoperative). However, due to the great penetration depth of the laser irradiation, large endothelial defects resulted beneath the stromal coagulations. In group II an initial refractive change of up to + 6.8 D was achieved and as a result of the reduced penetration depth, the endothelial cell damage was much reduced. Partial regression of the refractive effect occured in all subjects, which continued in higher refractive changes during the 2nd postoperative year. The refractive effect at 12 months was + 0.6 to + 1.5 D in group I and + 0.9 to + 5.7 D in group II. At 12 months the induced astigmatism was 0.5 to 2.2 D in group I and 0.3 to 1.6 D in group II. No serious adverse effects were noticed. Conclusion: A continously emitting laser diode working at a wavelength of 1.87 μm can be used to correct hyperopia by means of LTK safely and effectively. Regression occurs predominantly in the first 6 postoperative months. Further studies must be conducted to determine the importance of patient inherent parameters such as age in establishing a nomogram.   相似文献   
72.
From a Pediatric Rheumatology Clinic 361 children diagnosed as juvenile rheumatoid arthritis (JRA) according to American Rheumatism Association-JRA criteria were studied retrospectively for their clinico-immunological profile. The mean age of onset in systemic, pauciarticular and polyarticular onset, JRA subtypes were 5.2, 6.8 and 7.2 years respectively. There was male preponderance in systemic and pauciarticular JRA. In seropositive polyarticular JRA, girls outnumbered boys. The frequency of occurence of systemic, pauciarticular and polyarticular disease was 87 (24%), 108 (30%) and 166 (46%) respectively. The systemic onset disease was dominated by extra-articular manifestations in terms of fever (100%), rash (57%), hepatomegaly (51%) and lymphadenopathy (25%). The pauci- and polyarticular illnesses were commonly dominated by joint involvement, morning stiffness, and in few patients, by extra-articular manifestations also. The joints were involved symmetrically. Most commonly involved joints in order of decreasing frequency were knee, ankle, wrist and elbow in all the subtypes. Anemia and leucocytosis were observed in majority with higher frequency in systemic onset JRA. The rheumatoid factor (RF) was present in 15% of polyarticular JRA. RF was also present in 7 and 9% of patients with pauciarticular and systemic subtypes respectively. The antinuclear antibody was positive in only 3 out of 66 patients in whom the test was carried out. The demographic profile and trends in clinical features were similar to the studies reported on caucasian population with difference in the actual frequency of various clinical features.  相似文献   
73.
Acyclovir treatment was used in a randomized, double-blind, placebo-controlled clinical trial with parallel groups to test the hypothesis that herpes virus infections are involved in the pathogenesis of multiple sclerosis (MS). Sixty patients with the relapsing-remitting form of MS were randomized to either oral treatment with 800 mg acyclovir or placebo tablets three times daily for 2 years. The clinical effect was investigated by an extensive test battery consisting of neurological examinations, neuro-ophthalmological and neuropsychological tests, and evoked potentials. Results were based on intent-to-treat data and the primary outcome measure was the exacerbation rate. In the acyclovir group (n = 30), 62 exacerbations were recorded during the treatment period, yielding an annual exacerbation rate of 1.03. The placebo group (n = 30) had 94 exacerbations and an annual exacerbation rate of 1.57. Thus, 34% fewer exacerbations were encountered during acyclovir treatment. This difference in exacerbation rate between the treatment groups was not significant (P = 0.083). However, this trend to a lower disease activity in acyclovir-treated patients was supported in subsequent data analysis. If the patients were grouped according to exacerbation frequencies, i.e. into low (0–2), medium (3–5) and high (6–8) rate groups, the difference between acyclovir and placebo treatment was significant (P = 0.017). Moreover, in a subgroup of the population with a duration of the disease of at least 2 years providing an exacerbation rate base-line before entry, individual differences in exacerbation rates were compared between the 2-year pre-study period and the study period in acyclovir-treated (n = 19) and placebo (n = 20) patients and acyclovir-treated patients showed a significant reduction of exacerbations (P = 0.024). Otherwise, neurological parameters were essentially unaffected by acyclovir treatment and there were no convincing signs of reduced neurological deterioration in the acyclovir group. This study indicates that acyclovir treatment might inhibit the triggering of MS exacerbations and thus suggests that acyclovir-susceptible viruses might be involved in the pathogenesis of MS. This possibility warrants further investigation.  相似文献   
74.
The treatment of choice in progressive hydrocephalus is drainage of cerebrospinal fluid in order to reduce elevated intracranial pressure (ICP). Defining the right moment for surgical intervention, however, in a hydrocephalic infant on the basis of clinical signs alone can be a difficult task. Clinical signs of raised ICP are known to be unreliable and sometimes even misleading. In the present study, the relationship between long-term anterior fontanelle pressure (AFP) measurements and clinical signs was investigated in 37 infants with hydrocephalus. The decision as to whether to operate or not was based on clinical signs alone; AFP values were not taken into account. There was an overall difference between the non-operated group and the preoperative measurements in the operated group, and also between the preoperative and the postoperative measurements in the latter, in regard to both AFP measurements and clinical signs. Almost all preoperative AFP values were increased. The direct correlation () between most individual clinical signs and AFP levels, however, was low (=0.15–0.41). The clinical sign tense fontanelle showed the best correlation with the AFP levels (=0.75). Furthermore, using logistic regression analysis, no combination of clinical signs could be found which reliably predicted the AFP. The relationship between the AFP pressure variables and clinical signs was also examined. The pathological A-waves occurred only in the presence of raised (baseline) AFP, a situation in which considerably more frequent B-waves were observed as well. It was concluded that clinical signs of raised ICP in infantile hydrocephalus are not very reliable and AFP monitoring can therefore provide valuable information on intracranial dynamics in patients with dubious neurological manifestations of progressive hydrocephalus.  相似文献   
75.
Summary The worldwide incidence of prostate cancer differs greatly. The black population of the USA is at the head, while the Asian populations have the lowest incidence and mortality rates. Comparative geographic-pathologic autopsy studies on frequency and growth type of latent prostate carcinomas show that in populations with a lower incidence, for example Japan and Singapore, latent carcinomatous foci are not considerably rarer than in regions with high incidence. However, obvious differences are seen when comparing the size of the foci and the growth types. In countries with low incidence and mortality rate, the foci of the latent prostate carcinoma are small and show a slight proliferating tendency, whereas in countries with high incidence and mortality rate, they are frequently larger and more aggressive. Consequently, the different incidence of prostate cancer is not based on different initiation of malignant transformation, but on different promoting factors. In histologic-bioptical specimens from regions with high incidence and mortality rate, pluriform tumor types of malignancy grade G III and G II prevail. Definite causes of prostate cancer could not be detected by case control and migration studies up to now.Supported by the campaign Kampf dem Krebs e.V. der Deutschen Krebsgesellschaft  相似文献   
76.
挑刺阳性反应点治疗腰椎骨质增生38例   总被引:1,自引:0,他引:1  
试用三棱针挑刺腰部阳性反应点,治疗腰椎骨质增生38例,结果有效率100%,具有疗效好,费用低,疗程短,应用方便的特点.  相似文献   
77.
1 BACKGROUNDTheincidenceofCPis 0 .7per 1 0 0 0livebirths[1 ] .Becausecerebralpalsyinfluencesthewaychildrendevelop,itoftenresultsindevelop mentaldisability .Today ,more peoplehavecerebralpalsythananyotherdevelopmentaldis ability ,includingDownsyndrome,epilepsy ,andautism .Accordingtoasurveyconductedin1 986,2 .6%ofthepopulationofPakistaniaredisabled (includingbothphysicalandmentaldis abilities) .Childrenbetween 0~1 4 yearsinageconstitute 40 %ofthedisabled populationinPakistan .Routineme…  相似文献   
78.
目的:探讨子宫内膜癌的治疗及预后相关因素。方法:回顾性分析我科1991~1997年收冶的147例子宫内膜癌患者的临床病理资料,并全部随访。结果:147例患者、平均年龄56.1岁;5年生存率72.8%;临床表现不规则阴道出血135例、盆腔包块81例、白带增多38例及腹痛23例;绝经前病例为39.5%,已占相当比例,有年轻化趋势;临床病理分期愈晚,预后愈差;肌层侵犯的深度与淋巴结转移及病理组织学分级密切相关,深肌层浸润者,易淋巴结转移、病理组织学分级也差;手术为主、放疗、化疗为辅助治疗的综合治疗预后好、并发症少;孕激素对改善预后有一定的价值。结论:以手术为主的综合治疗是目前治疗子宫内膜癌的首选治疗措施;绝经前后的妇女出现不规则阴道出血等非特异性的妇科症状时,必须警惕子宫内膜癌的发生;临床病理分期、肌层浸润深度、病理组织学分级、淋巴结转移情况及孕激素的应用都是影响预后的相关因素。  相似文献   
79.
结缔组织增生性小圆细胞肿瘤2例并文献复习   总被引:1,自引:0,他引:1  
目的:分析结缔组织增生性小圆细胞肿瘤(DSRCT)的临床病理特征。方法:结合文献对2例相对少见的DSRCT进行临床、病理形态及免疫组化研究。结果:DSRCT由成团巢的小圆细胞和丰富的结缔组织间质组成。免疫组化:小圆形的肿瘤细胞vimentin( );desmin( );EMA( );CK( );NSE( )。结论:DSRCT为高度侵袭性肿瘤,主要累及腹腔或盆腔的腹膜,肿瘤由小圆细胞和丰富的结缔组织间质组成。  相似文献   
80.
对41例儿童旋毛虫病的临床观察   总被引:5,自引:0,他引:5  
为了解儿童旋毛虫病的临床特征,对1992~1995年就诊的41例儿童旋毛虫病进行分析。结果表明,患儿来自河南6个地区,主要因食猪肉馅饺子、烤羊肉串或食涮猪肉而感染。冬季为本病的高发季节。患儿平均年龄为8.8岁,男女之比为2.71。长期发热和嗜酸性粒细胞增多为本病的主要表现,仅少数患儿有肌痛、胃肠道症状和皮疹。眼睑水肿仅见于发病早期。血清学检查对诊断本病有重要意义。预防本病的关键措施是加强肉检和改变不良的饮食习惯。  相似文献   
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