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81.
82.
Suppurative corneal ulceration in Bangladesh   总被引:8,自引:0,他引:8  
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   
83.
Desmoplastic malignant melanoma (DMM) is a rare variant of spindle cell melanoma. We report a case of DMM of the forehead secondarily involving the orbit. The diagnosis was based on light microscopic features, including prominent peripheral cell nest formation and spindle cell fascicles in densely collagenous stroma. Immunohistochemical studies showed strong uniform staining for S100 antigen throughout the tumour. It was negative for HMB 45, smooth muscle actin, desmin, cytokeratins and Type IV collagen. Electron microscopy showed neither melanosomes nor myelin figures. The clinical and histological characteristics of desmoplastic malignant melanoma, and its differential diagnosis of malignant schwannoma, are discussed. DMM has a poor prognosis, since it tends to invade deeply, recur locally and metastasise readily.  相似文献   
84.
The history and clinical findings are presented of a patient who suffered from the uveal effusion syndrome over a 10-year period from 1956. The funduscopic appearance is illustrated both at the time of initial presentation and 36 years later. This condition typically affects healthy middle-aged men and causes recurrent, spontaneous, serous retinal and ciliochoroidal detachments, often resulting in significant visual impairment. Two separate hypotheses have been postulated to explain the pathogenesis of the uveal effusion syndrome, one relating to abnormally thickened sclera, the other to chronic bulbar hypotony. Both are discussed, as is the rationale behind the current management of this unusual condition.  相似文献   
85.
Of 5,218 patients who received EEG examination at our laboratory during a 9-month period in 1989, 241 showed the 7-13 Hz arch-shaped activity originating from over the Rolandic area known as mu rhythm. These subjects were divided into two groups as follows: Group 1, 171 subjects showing typical mu rhythm, i.e., recorded during wakefulness and not affected by visual stimulation but blocked voluntary movements or tactile stimuli; and, Group 2, 70 subjects showing atypical mu rhythm, i.e., accentuated or activated by drowsiness, photic stimuli, or hyperventilation. No difference between the two groups was found with regard to frequency, amplitude or origin of the mu rhythm. Age distribution for Group 1 showed a peak between the ages of 6 and 15 (67.5%), while that for Group 2 peaked between the ages of 11 and 15 (35.7%) considering high incidence in older age range. There was no significant difference between the two groups in regard to gender. Although both groups showed a high incidence of epilepsy, Group 2 showed higher incidence of intractable epilepsy (p less than 0.05), as well as of severe intracranial trauma and of organic brain disease. On EEG recorded among epileptic patients, paroxysmal discharge was more frequent in Group 2 (p less than 0.01), although no other difference between the two groups was observed. Atypical mu rhythm may indicate more severe epilepsy, and careful observation of patients with atypical mu rhythm is recommended.  相似文献   
86.
The regulation of interleukin-1 receptor (IL-1R) mRNA expression by IL-1 in a human lung fibroblast cell line (TIG-1) was investigated. After 2 h of stimulation with human recombinant IL-1 alpha or IL-1 beta, the levels of T cell/fibroblast-type IL-1R mRNA increased, and the elevation was sustained for at least 72 h. IL-1 also stimulated synthesis of prostaglandin E2 (PGE2) and secondary cAMP accumulation. Exogenously added PGE2 increased the levels of both IL-1R mRNA and intracellular cAMP. Forskolin, cholera toxin and 8-Bromo adenosine (8-Br-cAMP) all increased IL-1R mRNA levels. Indomethacin blocked IL-1 stimulation of IL-1R mRNA expression, PGE2 production and cAMP. 125I-labeled IL-1 alpha-binding studies showed that this cell line expresses 2.6 x 10(4) IL-1R per cell with a Kd of 5.1 x 10(-10) M. After treatment of the cells with IL-1, the level of IL-1R increased over that of control cells. PGE2 also increased IL-1R without alteration in its affinity. Cross-linking experiments indicate that this cell line expresses the 80-kDa receptor molecule before and after treatment with PGE2; the molecular mass corresponds to the T cell/fibroblast type I IL-1R. These results indicate that IL-1 does not directly stimulate expression of IL-1R mRNA or cell surface IL-1R, but only indirectly by stimulation of endogenous PGE2.  相似文献   
87.
Sharon Gohari  BS    Charles Gambla  MD    Mary Healey  RN    Gail Spaulding  RN    Kenneth B. Gordon  MD    James Swan  MD    Brian Cook  MD    Dennis P. West  PhD    Jean-Christophe Lapiere  MD 《Dermatologic surgery》2002,28(12):1107-1114
BACKGROUND: Human Skin Substitute (Apligraf, Organogenesis, Inc., Canton, MA) is a bi-layered tissue-engineered living biological dressing developed from neonatal foreskin. It consists of a bovine collagen matrix containing human fibroblasts with an overlying sheet of stratified human epithelium containing living human keratinocytes. Human Skin Substitute (HSS) appears to be immunologically inert, and has shown usefulness in the treatment of chronic and acute wounds. OBJECTIVE: Primary objectives were to evaluate the safety and efficacy of HSS in the treatment of full-thickness wounds in a prospective case series. Secondary objectives were to determine the rate of complete wound reepithelialization, incidence of complete wound healing, pain at wound site, overall cosmetic outcome, and patient satisfaction. METHODS: Fourteen patients were enrolled in the study, of which 12 were evaluable. HSS was applied in a blinded fashion to 6 of the patients immediately following Mohs or excisional surgery for skin cancer. The remaining 6 patients were allowed to heal by secondary intention. Both groups were evaluated at weekly appointments until complete reepithelialization occurred. During each evaluation, wound quality was assessed through the Vancouver Burn Scar Assessment Scale by the investigator and an independent blinded dermatologist. The investigator, blinded observer, and patient further evaluated the cosmetic outcome of the wound through the use of a Visual Analog Scale over a 6-month period. RESULTS: HSS patients and secondary intention patients were equivalent in comorbid factors such as pain, erythema, edema, exudate, infection, or hematoma between the groups. The incidence of complete wound healing at 6 months was 100% for both groups. Both groups also appeared to heal at similar rates, as defined by the complete reepithelialization of the wound. HSS patients ultimately resulted in more pliable and less vascular wounds as defined by the Vancouver Burn Scar Assessment Scale. Patient satisfaction with cosmetic outcome in both groups was positive at 6 months. CONCLUSIONS: HSS appears to be a safe, well-tolerated biological dressing with equivalent comorbid factors to secondary intention healing. HSS, however, seems to produce a more pliable and less vascular scar than those developed through healing by secondary intention. HSS also appears to produce more satisfactory cosmetic results when compared to secondary intention healing.  相似文献   
88.
Aneurysms of the inferior left ventricular wall represent only a small fraction of all aneurysms that have been reported in surgical series. And in comparison to anterior left ventricular aneurysms, a comparatively higher percentage of reported inferior wall aneurysms was classified as false. A 73-year-old male was admitted for acute inferior myocardial infarction. Three weeks after admission, cardiac catheterization was carried out. Coronary arteriography revealed triple vessel disease and left ventriculography showed an aneurysm of the inferior left ventricular wall, whose feature near the mitral annulus was multiple fenestrations. Left ventricular aneurysmectomy and aortocoronary bypass grafting to the left anterior descending artery were simultaneously performed under cardiopulmonary bypass with moderate hypothermia. The pathological feature was a true aneurysm. The postoperative course was uneventful.  相似文献   
89.
An unusual form of scotopic electroretinogram with a bright white stimulus, which consisted of a rectangular a-wave of normal amplitude and a b-wave of supernormal amplitude, was recorded in three patients with cone dysfunction. In addition to poor visual acuity, abnormal color vision and reduced amplitude of the photopic electroretinogram, these patients showed a 2-log unit elevation of the dark-adaptation threshold. Funduscopic examination and fluorescein angiography revealed fine granular pigment disturbances at the mascula. The relationship between the response of the dark-adapted electroretinogram versus stimulus intensity was unique to these patients. The b-wave thresholds were elevated by 1 log unit. The b-waves were reduced in amplitude and markedly delayed in implicit time to dim stimuli, but supernormal in amplitude and normal in implicit time to bright stimuli.Abbreviations GMP guanosine monophosphate  相似文献   
90.
Objective. The medical practitioner is faced with an increasing list of protocols and algorithms related to patient care. These recommendations are often difficult to recall, particularly in stressful emergency situations. Using advanced cardiac life support (ACLS) protocols, we built a computer-based system to exhibit precompiled response plans for medical emergencies. To validate the usefulness of this prompting device, we tested application of two of the nine ACLS algorithms, pulseless ventricular fibrillation/ventricular tachycardia (Vfib/Vtach) and bradycardia, in a simulated operating room (OR) environment.Methods. The system utilized the software authoring system IconAuthor (Aimtec Inc., Nashua, NH) and a touch-screen monitor (DiamondScan, Microtouch, Methuen, MA). Prior to testing our system, all 39 subjects were given time to familiarize themselves with its operation. Subsequently, all subjects were videotaped while managing a standard simulated anesthetic. During the anesthetic, the subjects were presented with two emergency scenarios, not viewed during the familiarization period. The electrocardiographic (EKG) signals for normal sinus rhythm, ventricular fibrillation, and second-degree heart block were presented. By random selection, the prompter was available to half of the subjects for help with arrhythmia management (experimental group), while to half it was not (control group).Results. A total of 39 subjects completed the exercise. Use of the prompter enabled significantly more subjects to administer correct drugs and dosages during ventricular fibrillation. The correct lidocaine dose was chosen more often by the experimental group than by the control (p=0.015); similarly MgSO4 was appropriately ordered more often in the experimental group (p=0.003). During second-degree heart block, atropine was correctly followed with a dopamine infusion (p=0.004), and epinephrine infusion was ordered for refractory bradycardia (p=0.002) more often in the experimental than the control group.Conclusions. These data demonstrate the value of a prompting device at the anesthesia workstation. We foresee the use of such prompters in many areas of medicine.This study was made possible by a grant from the Anesthesia Patient Safety Foundation. Results were presented, in part, at the meeting of the STA/SEA Orlando, Florida, January 1994.  相似文献   
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