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A 65-year-old man developed acute limb ischemia, severe abdominal wall and lower limb livedo reticularis following a coronary angiogram. The differential diagnoses of acute limb ischemia and multiple cholesterol emboli syndrome (MCES) are discussed. This work was performed at Long Island Jewish Medical Center, 270-05, 76th Avenue, New Hyde Park, NY 11040.  相似文献   
3.
A rare case of a maxillo-mandibular band in a 21 year female patient is reported. Possibility of its being a remnant of buccaphary geal membrane is discussed in the light of clinical and histological findings.  相似文献   
4.
Of 132 children with bladder stones seen in 1 year, 94% were boys and 73% were aged between 1 and 5 years. Significant malnutrition and evidence of vitamin deficiency were absent. Wheat bread was the dietary staple, while the intake of milk and dairy products, eggs and meat was very low. Analysis of 29 stones showed them to consist mainly of calcium oxalate and uric acid, with small amounts of calcium phosphate and magnesium ammonium phosphate in some cases. The composition of the surface and central parts of the stones, examined in 20 cases, was usually different. The nucleus was formed almost entirely of calcium oxalate and uric acid in four and three cases respectively, whereas the surface layers were composed of other ingredients. In another case the nucleus was composed entirely of xanthine, which indicated a diagnosis of xanthinuria.  相似文献   
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This is a prospective, non-randomized study to evaluate and compare the results, morbidity and surgical time for endonasal carbon-dioxide laser assisted dacryocystorhinostomy and external dacryocystorhinostomy. 70 consecutive patients of chronic dacryocystitis with nasolacrimal duct obstruction were selected for the study. 36 patients under went endonasal CO2 laser assisted dacryocystorhinostomy and 34 had external dacryocystorhinostomy. Selection of the type of operation was left to the patient's choice. All the patients had preoperative counseling and both the procedures were explained in detail with their advantages and disadvantages. Patients not willing for the external incision were selected for endonasal laser assisted dacryocystorhinostomy and others were operated via external approach. Silicone tubes were put in all the patients for three months after surgery. The final follow up was 12 months after the removal of silicone tubes. The patency of the lacrimal passage was confirmed by irrigation, and patients were questioned about their symptoms. The success rates, 12 months after removal of silicone tubes were 100% in endonasal CO2 laser assisted dacryocystorhinostomy and 88.24% in external dacryocystorhinostomy. The surgical time of endonasal laser assisted dacryocystorhinostomy was 38 minutes as compared to 62 in external dacryocystorhinostomy. Complication rate in both groups was almost equal. Thus, we came to the conclusion that Endonasal CO2 laser assisted dacryocystorhinostomy is a better surgical option to external dacryocystorhinostomy in cases of chronic dacryocystitis with nasolacrimal duct obstruction, with shorter surgical time.  相似文献   
7.
Measuring the efficacy of antiepileptic drugs.   总被引:4,自引:0,他引:4  
Clinical trials of new antiepileptic drugs (AEDs) include regulatory studies aimed at demonstrating efficacy and reasonable safety, post-marketing open-open label studies and longer term outcome studies. Regulatory trials involve a carefully selected population of patients and are conducted under rigorously standardised conditions. Data from such studies cannot often be translated into clinical practice. Pragmatic post-marketing studies using flexible dosing schedules allow clinicians to better judge the utility of the new drug in a wider population of patients with epilepsy and decide the most appropriate dosing schedules. This paper discusses some of the issues surrounding the measurement of efficacy of new AEDs in both pre- and post-marketing phases of their development. All of the newer AEDs are initially used in patients with refractory partial seizures as adjunctive treatment. These trials are generally parallel-group studies although cross-over designs have been employed. The use of placebo-control is uncontroversial in this type of study. Efficacy endpoints are generally manipulations of seizure frequency on study drug compared to control. Global outcome measures and health related quality of life scores can also be used to measure efficacy. As the standard AEDs are associated with a high rate of seizure remission in patients who receive them as monotherapy, demonstration of superior efficacy of a new agent in a comparative trial will require large numbers of patients in a design that takes into account the natural history of treated epilepsy. Comparing investigational agents to a standard AED in an 'active-control' study with demonstration of equivalent efficacy would seem to be an acceptable way of assessing efficacy of new AEDs in this population. Some regulators, however, do not accept equivalence as proof of efficacy and insist on demonstration of superiority compared to a control. The use of placebo alone in the control group is ethically dubious. Several innovative study designs have, therefore, been used to satisfy regulatory requirements, while maintaining patient safety including withdrawal to monotherapy using high versus low dose comparators. Observational outcome studies provide the best opportunity of exploring the long-term utility of individual AEDs. Such studies largely follow standard clinical practice and need considerable time and resources. They can, however, yield valuable information about the effectiveness of AEDs in everyday clinical practice. Data from regulatory trials should be complemented by postmarketing studies and longer term studies of outcome to help clinicians decide the best way of utilising new AEDs and establishing their role in the therapeutic armamentarium.  相似文献   
8.
Using the finite element method, this study modeled a 4.0 x 13.0-mm IMZ implant, restored with a cast gold crown, to examine the influence of the polyoxymethylene (POM) intramobile element (IME) on the transmission of vertical and oblique forces. Stress concentrations in the bone and in components of the implant system were much greater under a 30-degree load than under an equal vertical load. Stress transmission to bone occurred chiefly in the crestal region, and these stresses were not reduced when the IME was modeled in POM rather than in titanium. Maximum stress concentrations occurred in the fastening screw.  相似文献   
9.
An 18-year old boy presented with a tumour involving a large part of the petrous bone. A radical resection of a petrous bone 'aneurysmal bone cyst' was achieved. A large defect in the dura adjoining the posterior surface of the petrous bone was made during surgery. Post-operative MR imaging showed complete tumour resection but herniation of cerebellum into the operative defect, a phenomenon probably assisting to seal the site of cerebrospinal fluid fistula.  相似文献   
10.
The torque-angular deformation in right axial rotation until failure of the ligamentous occipito-atlanto-axial complex subjected to variable loading rate (dynamic) axial torque was characterized using a biaxial MTS system. A special fixture and gear box that permitted right axial rotation of the specimen until failure without imposing any additional constraints were used to obtain the data. The specimens were divided into three groups and tested until failure at three different dynamic loading rates: 50, 100, and 400 degrees/s. A previous study by the authors provided data for quasi-static (4 degrees/s) loading conditions. The torque versus rotation curves can be divided into two straight regions and two transition zones. The plots clearly indicated that at loading rates higher than 4 degrees/s, the specimens became stiffer in the region of steadily increasing resistance prior to failure. The increase in stiffness was maximum at 100 degrees/s. The stiffness decreased somewhat at 400 degrees/s in comparison with 100 degrees/s, but this decrease was not significant. The resulting torque-right axial rotation curves were also examined to estimate the magnitude of maximum resistance (torque) and the corresponding angular rotation value. The average maximum resistance torque increased from 13.6 Nm at 4 degrees/s to 27.8 Nm at 100 degrees/s. The corresponding right angular rotation data (65-78 degrees), however, did not show any significant variation with loading rate. Posttest dissection of the specimens indicated that the type of injury observed was related to the rate of axial loading imposed on a specimen during testing.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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