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11.
12.
We used morphological, biochemical and immunohistochemical methods to assess the response of Müller cells after experimental lensectomy-vitrectomy in rabbits. We observed widened intercellular spaces between the Müller cells and nerve fibers of ganglion cells, and increased electron opacity in the Müller cells of eyes injected with silicone oil. No apparent morphological changes were detected in the Müller cells of air-injected eyes. The specific and total activities of Müller cell-marker enzymes (glucose 6-phosphatase and glutamine synthetase) showed an initial increase, followed by a decrease. Glial fibrillary acidic protein immunoreactivity was not found in the Müller cells of the normal rabbit retina but was exhibited after surgery. Our results showed that markers of Müller cells associated with glycogenolysis and/or gluconeogenesis, glutamate-glutamine cycle and cytoskeletal protein metabolism were affected by the experimental lensectomy-vitrectomy.  相似文献   
13.
This study aimed to evaluate human antibody responses to diphtheria toxin subunits in various age groups. Antibodies against the intact diphtheria toxin and the diphtheria toxin subunits A and B were evaluated in 1319 individuals using a double-antigen ELISA. Although high levels of protection (83.6%, 95% CI 79.2-87.4) were found in children and adolescents, the middle-aged adult population was less protected (28.8%, 95% CI 24.3-33.6). An increase in age was associated with a decrease in the frequency of protected individuals in the 0-39-year age group (p <0.001). Anti-subunit B levels correlated well (p <0.01) with levels of antibodies against the intact toxin. In children aged < or =16 years, the intervals at which the peaks in geometric mean titres of anti-subunit B antibodies were observed were found to correlate with the ages at which booster doses are administered. Overall, males appeared to be more protected than females (OR 1.67, 95% CI 1.34-2.08, p <0.001). A small group of individuals had antibody levels of > or =0.1 IU/mL against the intact toxin, but did not have protective antibody against subunit B. Determination of anti-subunit B antibody levels should help in evaluating the effectiveness of diphtheria boosters and other aspects of diphtheria immunity.  相似文献   
14.
Purpose: to determine wheather an association exists between sensorineural hearing loss and pseudoexfoliation. Methods: Hearing thresholds were determined by using pure-tone au-diometry in 75 patients with pseudoexfoliation syndrome and in the control group of 75 subjects without pseudoexfoliation The groups were sex and age matched. Results: The frequency of  相似文献   
15.
OBJECTIVE: The purpose of this study was to evaluate the sensitivity and specificity of proximal upper limb motor nerve conduction study abnormalities in chronic inflammatory demyelinating polyneuropathy (CIDP), using standard percutaneous stimulations up to Erb's point. METHODS: Electrophysiologic data relating to proximal conductions of median and ulnar nerves of 22 patients with CIDP were retrospectively analyzed and compared to those of 22 controls with sensory neuropathy. Distal conduction results were also reviewed. RESULTS: The findings demonstrate independent high sensitivity of abnormal upper limb proximal nerve conduction studies in CIDP. Demonstration of conduction block of >20% and temporal dispersion of >15% had low specificity. However, conduction block was highly specific with cut-off values of >30% at axilla and >50% at Erb's point. Specificity was considerably improved using a cut-off value of >30% at proximal levels for temporal dispersion. Diagnostic sensitivity improved significantly with proximal studies with the criteria used in this population. No adverse effects had occurred as result of proximal stimulations. CONCLUSIONS: Proximal studies are safe, sensitive and reliable procedures in cases of suspected CIDP. Their use appears justified although adequate cut-off values are desirable to optimize their specificity. SIGNIFICANCE: This study indicates that proximal upper limb nerve conductions are appropriate in investigating suspected CIDP, as detailed in recently established electrophysiologic criteria. However, specificity is largely dependent on cut-off values for conduction block and temporal dispersion.  相似文献   
16.
The introduction of bisphosphonates has increased in the last decade following their indication for metastatic bone diseases, osteoporosis, hypercalcaemia of malignancy and Paget’s disease. Although bisphosphonates have been used clinically for more than three decades there have been no documented long-term complications of their effects on the jaws until recently, where there is now growing evidence of the influence of bisphosphonates on osteonecrosis of the jaws. The aim of this paper is to report a case of this newly described complication, to review this phenomenon, including the clinical implications and to reiterate current clinical guidelines for management of patients in which bisphosphonate therapy is indicated. To the best of our knowledge this is the first reported case of bisphosphonate-induced necrosis of the jaw in South Africa.  相似文献   
17.
Background and aims The aim of this study is to evaluate the predictive accuracy of different scoring systems on surgery for perforated peptic ulcer referred to an academic department of general surgery in a tertiary reference center. Patients and methods Seventy-five consecutive patients (Male/female ratio = 64:11; mean age, 44 years; range, 16–85) with perforated peptic ulcer disease were investigated. Disease severity scores and mortality predictions were calculated using the collected data during admission. Discrimination and calibration characteristics of each system, namely, the acute physiology and chronic health evaluation II and III, the simplified acute physiology score II, and the mortality probability models (MPM) II, were determined by using the area under receiver operating characteristics curve and the Hosmer–Lemeshow goodness-of-fit test, respectively. Results Among the 75 patients included, there were eight (10.6%) mortalities. All systems had a reliable power of discrimination and calibration. Among the systems tested, MPM II was the best performing as far as discrimination and calibration characteristics were considered. The parameters of MPM II system that were related to systemic perfusion of the patient were significantly positive in patients who died compared to those who survived. Conclusions MPM II that predicted mortality at admission is better than the other systems in predicting mortality. Results also indicate the importance of maintenance of systemic perfusion of the patient at the early phases of peptic ulcer perforation.  相似文献   
18.
A retrospective study had been done at the outpatient clinic sub division of Pediatric Gastroenterology, Dr. Pirngcdi Hospital Medan, comprising patients from 1 January 1985-31 December 1987. There were 874 patients. Three hundred seventy eight (43.25%) patients consisting of 210 (55.56%) males and 168 (44.44%) females had intestinal parasitic infestations. The youngest patient was 5 months and the oldest was 14 years and 3 months. Ascaris lumbricoides was found in 215 patients (24.60%) while Trichuris trichiura, hookworm, Oxyuris vermicularis, Hymenolepis nana, and Taenia were in 152 (17.39%), 13 (1.49%), 4 (0.46%), 15 (1.72%) and 4 (0.46%) cases respectively. Entamoeba histolytica was found in 121 (13.84%) and Giardia lamblia in 16 (1.83%) patients. The highest age specific attack rate was found in the age group of 5-10 years (65.67%). Ascaris lumbricoides was most frequently found namely in 100 children (26.46%), followed by Entameba histolytica in 73 (19.31%) and mixed infestation of Ascaris lumbricoides and Trichuris trichiura in 68 (17.99%) patients. One hundred seventy three (66.28%) under five patients with intestinal parasitic infestation had malnutrition while of the 433 under fives without intestinal parasitic infestation only 201 (46.42%) suffered from malnutrition (P less than 0.001).  相似文献   
19.
Subclinical adrenocortical insufficiency in renal amyloidosis   总被引:1,自引:0,他引:1  
In order to investigate the functional significance of possible adrenal amyloid infiltration in patients with renal amyloidosis, we performed corticotrophin stimulation tests in 15 patients having renal amyloidosis with no clinical evidence of adrenocortical insufficiency and 12 controls. In 7 of the patients, the cortisol increments obtained during the test were found to be consistent with primary adrenal insufficiency due to possible amyloid infiltration of the adrenal cortex; in contrast, in all control subjects, adrenal responses to the test were regarded as sufficient for proper adrenal function.  相似文献   
20.
Abdominal Stab Wounds in Children: an 18-Year Experience   总被引:1,自引:0,他引:1  
Objective: Evaluation of the diagnosis, management, and the role of selective treatment in children with abdominal stab wounds. Patients and Methods: 59 children (56 male and three female) were included in the study. The patients' median age was 11.8 years (range, 5–14 years). Time between injury and admission was about 3 h. Laparotomy was performed in 44 patients (74%). Solid organ injury was detected in 32 of these patients (73%) and could not be observed in twelve (27%). 15 patients (26%) were treated conservatively, and only one (6.6%) underwent laparotomy during the follow-up. The stomach was the most frequently injured organ (ten patients), followed by the intestines (nine patients). Types of surgical treatment were as follows: primary suture in 28 patients, resection-anastomosis in three, and osteotomy in two. Results: Some prognostic factors such as presence of abdominal organ evisceration and pneumoperitoneum were not significantly correlated with intraabdominal organ injury, whereas some other risk factors such as acute abdomen on admission (p < 0.002) or abdominal clinical and hemodynamic findings (p < 0.001) showed significant correlation with intraabdominal organ injury. The relative risk (odds ratio) of developing an intraabdominal organ injury was > 2 for patients with signs of an acute abdomen on admission. Postoperative complications were observed in five patients with organ injuries. None of our patients died. Conclusions: Conservative treatment can be safely performed in most children with abdominal stab injuries. Signs of major internal hemorrhage or generalized peritonitis are an absolute indication for emergency operation for abdominal stab wounds. Peritoneal penetrations, free air on the abdominal X-ray, and omental or intestinal evisceration are poor indicators of significant organ injuries, and patients presenting these signs shold be closely followed up for developing acute abdominal symptoms. Received: November 2, 2001; revision accepted: February 15, 2002  相似文献   
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