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Laser treatment with blue-green argon, green argon and/or krypton red was performed on 578 eyes in 443 patients with neovascular age-related macular degeneration (AMD). The visual acuity was examined in all eyes 2 to 8 weeks after initial treatment and in 204 eyes in 167 patients 2 to 4 years after initial treatment. The short term results were as follow: 91/578 eyes (16%) had improved (greater than or equal to 2 lines on Snellen's charge or equivalent steps), 445/578 eyes (77%) remained unchanged and 42/578 eyes (7%) had deteriorated visual acuity (greater than or equal to 2 lines on Snellen's chart or equivalent steps). The reduction in visual acuity, may in about half of the 42 eyes be caused by too intensive laser application in the beginning of this study in 1983 and 1984 where treatment was applied with blue-green argon, which has now been abandoned. In the group with an observation time of 2 to 4 years, 42/204 eyes (21%) had improved, 119/204 eyes (58%) remained unchanged and 43/204 eyes (21%) had a deteriorated visual acuity. In the 204 eyes the subretinal neovascular lesion(s) were located extrafoveally in 52 eyes, juxtafoveally in 114 eyes and subfoveally in 38 eyes. It is to be pointed out, that even patients with a pre-laser visual acuity of 6/60 or worse obtained an improvement of visual acuity in 12/27 eyes. About 40% of the eyes needed re-treatment from 1 to 8 times. It is unknown whether the obtained results are to be considered marginal or more substantial.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Summary During the period 1980 through 1989 a total of 1029 cases of fatal poisoning (638 men and 391 women) were examined at the Department of Forensic Medicine, Aarhus University, Denmark. In 68% of the cases death had been caused by drugs, whereas acute alcohol poisoning and carbon monoxide accounted for 15% and 14% of the cases, respectively. Alcohol was detected in more than half of the 1029 fatal poisoning cases, and in 42% of all cases the blood alcohol concentration was above 0.8 g/kg. In 57% of the cases death was categorized as accidental, only in 31% of the cases as suicide. Accidental deaths were especially predominant amongst drug and/or alcohol abusers. Propoxyphene was the drug found to have caused most fatal poisonings during the decade (30% of the drug-related deaths). Most of the propoxyphene-related deaths occurred during the early and mid-eighties. Barbiturate poisonings were quite frequent during the first half of the eighties. However, the number of deaths caused by barbiturates decreased significantly after 1986, when most barbiturates were withdrawn from the market. The number of deaths caused by narcotics and analgesics increased during the survey period, while no specific tendency was observed concerning antidepressants.  相似文献   
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Two cloned DNA fragments, one derived from an alpha satellite subfamily common to chromosomes 13 and 21, and the other derived from a similar subfamily common to chromosomes 14 and 22, have been used as biotinylated probes in in situ hybridization studies. Under high stringency conditions, chromosome specific centromeric labelling can be obtained. The applications of this technique in clinical situations are illustrated on metaphases from a fetus with trisomy 21, a fetus with trisomy 13, and a child with clinical features of cat-eye syndrome.  相似文献   
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Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy.  相似文献   
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Goei  R; Baeten  C; Arends  JW 《Radiology》1988,168(2):303-306
Sixteen cases of histopathologically proved solitary rectal ulcer syndrome were encountered. Fifteen patients underwent barium enema study; in nine cases the findings--including rectal stricture, granularity of the mucosa, and thickened rectal folds-were nonspecific. In six cases the study was normal. All patients had a long history of defecation disorders, and defecography was performed in all. In seven cases, intussusception of the rectal wall was seen; in another case the intussusception was accompanied by a rectocele. One case showed rectal prolapse. In four cases, failed relaxation of the puborectalis occurred and prevented the passage of the bolus; in another case there was abnormal perineal descent. In two patients studies were normal. In patients with defecation disorders, the possibility of this syndrome should be considered. Defecography is the method of choice for establishing the diagnosis.  相似文献   
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