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排序方式: 共有4116条查询结果,搜索用时 15 毫秒
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Suppurative corneal ulceration in Bangladesh 总被引:8,自引:0,他引:8
AAS Dunlop MB BS ED Wright MRCPath † SA Howlader‡ I Nazrul‡ R Husain‡ K McClellan FRACO § FA Billson FRACO § 《Clinical & experimental ophthalmology》1994,22(2):105-110
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season. 相似文献
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W K Chong M Paley I D Wilkinson M A Hall-Craggs B Sweeney M J Harrison R F Miller B E Kendall 《AJNR. American journal of neuroradiology》1994,15(1):21
PURPOSETo document differences in the cerebral proton MR spectra of patients with early and late stages of human immunodeficiency virus (HIV) infection.METHODWe studied the relative N-acetyl-aspartate (NAA) levels by localized proton spectroscopy of the parietooccipital region of the brain in 43 HIV-seropositive patients, including 26 with an acquired immunodeficiency syndrome (AIDS)-defining diagnosis, and in eight control subjects.RESULTSReduced relative NAA levels were shown in those HIV-1-seropositive patients: 1) with AIDS against HIV-1-seropositive patients without AIDS (P < .04); 2) with HIV-1-associated cognitive/motor complex against neurologically healthy patients (P < .007); 3) with encephalopathic changes on MR against those with normal imaging (P < .001); and 4) on follow-up against their results on initial study (P < .03).CONCLUSIONSBy clinical (Centers for Disease Control classification) and radiologic (MR evidence of white-matter disease) criteria indicating late-stage HIV infection, reduced relative levels of NAA have been demonstrated. Spectroscopic abnormalities can be quantitatively tracked with time. This paper demonstrates the clinical use of detecting NAA as a putative in vivo measure of the neuronal loss that has been demonstrated in postmortem studies of patients with AIDS. This neuronal loss, which is believed to underlie the HIV-1-associated cognitive/motor complex, is thought to be attributable directly or indirectly to the presence of HIV in the brain. Proton spectroscopy may serve as a quantitative noninvasive indicator of this aspect of cerebral involvement in HIV disease. 相似文献
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Levels of plasma Von Willebrand Factor (vWF) are known to be influenced by ABO Blood Group but such an influence on platelet vWF is not known. Forty-three healthy donors had blood drawn for measurement of plasma and platelet vWF, both antigenic (vWF:Ag) and functional (RCo). Twenty-six were Group O and seventeen were Group A. Groups did not differ in age, platelet count, hemoglobin, white cell counts, platelet rich plasma counts nor length of in vitro storage of samples prior to assay. Plasma levels of vWF:Ag and RCo was lower in Group O as expected. Platelet RCo was lower in Group O and such a trend was present for vWF:Ag. This influence of ABO Groups on platelet vWF was modest compared to that on plasma vWF. 相似文献
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Disturbances in neural circuitry including the basal ganglia and prefrontal cortex have been hypothesized to be a cause of obsessive-compulsive disorder (OCD). Because eye movements are often impaired in neurologic diseases affecting these brain areas, oculomotor functioning was assessed in 17 unmedicated patients with OCD and in 25 normal controls. As compared with control subjects, patients with OCD demonstrated low-gain (slow) pursuit eye movements and an increased frequency of square wave jerk intrusions, but no increase in anticipatory saccades. In addition, several OCD patients showed an unusual pattern of intrusive, brief epochs of high-gain (fast) pursuit lasting on the order of 50 to 130 msec. These epochs of fast pursuit moved the eyes ahead of the target being tracked, and were terminated by corrective reversal saccades. Studies of eye movement abnormalities may provide an informative neurophysiologic approach for studying disturbances in basal ganglia and frontal cortical function that have been observed in functional neuroimaging and neuropsychological studies of OCD. 相似文献
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Alcohol versus Mnemosyne--blackouts 总被引:1,自引:0,他引:1
D F Sweeney 《Journal of substance abuse treatment》1989,6(3):159-162
Blackouts induced by alcohol, in spite of their frequent occurrence, remain something of an enigma. This article reviews the knowledge of the blackout and of memory theory to date, and proposes a definition for this amnestic event. After establishing a definition, the article comments on the clinical significance, both from a medical and a medical-legal perspective. 相似文献
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Anal fissure in Crohn's disease 总被引:7,自引:0,他引:7
There is little information on the natural history of anal fissure in Crohn's disease. The case notes of all new patients with Crohn's disease attending one hospital between 1977 and 1983 were reviewed: there were 61 patients with this diagnosis and an unhealed anal fissure as the only anal lesion. Of these 61 patients the fissure healed in 42 (69 per cent) during medical treatment of the intestinal disease. Ten patients (16 per cent) developed other anal lesions and in the remaining nine patients the fissure remained unhealed at the time of rectal excision (six) or last out-patient attendance (three). Activity of the fissure did not reflect disease activity elsewhere in 11 cases in whom healing of the fissure occurred despite progressive intestinal disease subsequently requiring resection. This study validates the policy of conservative management of anal fissure in Crohn's disease with anal surgery (required in 9.8 per cent of patients in this series) being reserved for the development of other anal disease. 相似文献
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