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排序方式: 共有814条查询结果,搜索用时 375 毫秒
61.
Neepa M Thacker Federico G Velez Joseph L Demer Arthur L Rosenbaum 《Journal of AAPOS》2005,9(2):174-178
BACKGROUND: Rectus muscle involvement in thyroid ophthalmopathy is well documented. The inferior rectus is the most frequently involved, followed by the medial, superior, and infrequently the lateral rectus. This study reports involvement of the superior oblique muscle as a contributory cause of restrictive strabismus in patients with thyroid ophthalmopathy. METHODS: This is a retrospective review of four patients with known thyroid ophthalmopathy who presented with incomitant vertical strabismus, A-pattern, overdepression in adduction, underelevation in adduction, and incyclotorsion. All patients underwent preoperative orbital imaging. Two of the four patients had previous orbital decompressions. All patients underwent surgery on the SO muscle. RESULTS: Preoperative scans showed enlargement of one or both SO muscles in all patients and intraoperative forced duction testing revealed restriction to elevation in adduction in all cases. Preoperative A-pattern ranged from to 6 to 22 prism diopters. All subjects had preoperative incyclotorsion, ranging from 2 and 14 degrees. Improvement of the versions, hypertropia, and cyclotorsion followed surgical weakening procedures on the SO muscle. CONCLUSION: Thyroid ophthalmopathy may involve the SO muscle. Clinical manifestations include preoperative A-pattern strabismus, incyclotorsion, and restrictive limitation to elevation in adduction. Orbital imaging documents SO muscle enlargement. Awareness of SO involvement in thyroid ophthalmopathy assists the surgeon to develop a more precise surgical strategy to correct the hypotropia. 相似文献
62.
63.
K T Bellian J G Thacker C G Tribble D M Powell D G Becker C A Zimmer R F Morgan R F Edlich 《The American surgeon》1991,57(9):591-601
Standardized reproducible tests have been developed to determine the biomechanical performance of cardiovascular needles. The parameters used to assess performance were: 1) sharpness, 2) resistance to bending, and 3) ductility. Four comparable groups of tapercut and taper point cardiovascular needles were selected from different manufacturers for these biochemical studies. The results of this testing demonstrated that needle geometry, needle composition, and the manufacturer were important determinants of needle performance. When comparable needles were evaluated, the biochemical performance of cardiovascular needles manufactured by Ethicon, Inc. (Somerville, NJ) were superior to needles produced by other manufacturers. The superior performance characteristics of the cardiovascular needles produced by Ethicon, Inc. were related to their unique stainless steel alloy, American Society for Testing Materials 45500, which has greater yield and tensile strengths than the alloy used by the other manufacturers. This stainless steel alloy was ideal for the production of tapercut needles, which combined some of the features of a reverse cutting edge needle and taper point needle. Its very short cutting edges allowed it to penetrate the membrane at considerably lower penetration forces than were encountered with comparable taper point needles. In addition, the investigation indicated that the trocar point cardiovascular needles produced a large triangular defect whose diameter was much larger than that of the needle body. For this reason, the use of the trochar point needle is not recommended in cardiovascular surgery. 相似文献
64.
McDonnell SM Yassin AS Brown WG Perry HN Thacker SB 《Prehospital and disaster medicine》2007,22(5):396-405
To assist field workers in program evaluation and to explicitly discuss program strengths and weaknesses, a practical method to estimate the effectiveness of public health interventions within the existing program capacity was developed. The method and materials were tested in seven countries (Afghanistan, Zimbabwe, Tanzania, Uganda, Guatemala, the Philippines, and Ghana). In this method, four core components are assessed using a questionnaire: (1) the efficacy of the intervention; (2) the level of existing human resources (i.e., quality of recruitment, training, and continuing education); (3) the infrastructure (i.e., supplies, salary, transportation, and supervision); and (4) the level of community support (i.e., access and demand). Using the assessment tool provided, program staff can determine if all necessary elements are in place for a successful program that can deliver the specific intervention. Based on the results of the assessment program, weaknesses can be identified, explicitly discussed, and addressed. The usefulness of this tool in humanitarian relief may be twofold: (1) to assess the design and implementation of effective programs; and (2) to highlight the inevitable need for capacity building as the disaster situation evolves. 相似文献
65.
Anthony J. Weekes Angela K. Johnson Daniel Troha Gregory Thacker Jordan Chanler-Berat Michael Runyon 《The Journal of emergency medicine》2017,52(2):137-150
Background
Right ventricular dysfunction (RVD) in pulmonary embolism (PE) has been associated with increased morbidity. Tools for RVD identification are not well defined. The prognostic value of RVD markers to predict serious adverse events (SAE) during hospitalization is unclear.Objective
Prospectively compare the incidence of SAE in normotensive emergency department patients with PE based upon RVD by goal-directed echocardiography (GDE), cardiac biomarkers, and right-to-left ventricle ratio by computed tomography (CT). Simplified Pulmonary Embolism Severity Index (sPESI) was calculated. Deaths and readmissions within 30 days were recorded.Methods
Consecutive normotensive PE patients underwent GDE focused on RVD (RV enlargement, hypokinesis, or septal bowing), serum troponin, and brain natriuretic peptide (BNP), and evaluation of the CT ventricle ratio. In-hospital SAE and complications within 30 days were recorded.Results
We enrolled 123 normotensive PE patients (median age 59 years, 49% female). Twenty-six of 123 (26%) patients had one or more SAE. RVD was detected in 26% by GDE, in 39% by biomarkers, and in 38% with CT. In-hospital SAE included one death, six respiratory interventions, six dysrhythmias, three major bleeding episodes, and 21 hypotension episodes. Forty-one percent of patients RVD positive by GDE had SAE, compared to the 18% RVD negative by GDE. Odds ratios for GDE, CT, BNP, troponin, and sPESI for SAE were 3.2 (95% confidence interval [CI] 1.2–8.5), 2.0 (95% CI 0.8–5.1), 3.3 (95% CI 1.3–8.6), 4.2 (95% CI 1.4–13.5), and 2.9 (95% CI 1.1–8.3), respectively. Five patients had non-PE-related deaths within 30 days.Conclusion
The incidence of SAE within days of PE was significant in our cohort. Those with RVD had an increased risk of nonmortality SAE. 相似文献66.
67.
H Melbye B P Berdal B Straume H Russell L Vorland W L Thacker 《Scandinavian journal of infectious diseases》1992,24(5):647-655
Etiology and clinical manifestations have been studied in 153 adult patients with lower respiratory tract infection, and the results are presented according to clinical and radiographic diagnosis. Laboratory investigations revealed that bacterial infection, mycoplasma and chlamydia included, occurred as often in 22 patients whose clinical diagnoses of pneumonia were not evident radiographically, as in 20 patients with radiographic pneumonia. In the latter group significantly higher values of erythrocyte sedimentation rate and C-reactive protein were demonstrated. The most common pathogen was influenzavirus A, followed by respiratory syncytial virus, Streptococcus pneumoniae, and Mycoplasma pneumoniae. Chlamydia pneumoniae infection was found in 3 patients with radiographic pneumonia. The study supports the traditional view that patients with a positive chest radiograph as a rule present more serious manifestations of lower respiratory tract pathology than patients with a normal radiograph. However, as only 1/9 patients with pneumococcal infection and 2/7 with mycoplasmal infection had radiographic evidence of pneumonia, radiography alone did not seem to offer sufficient information for selecting patients for antibacterial therapy. 相似文献
68.
Michael A. Towler M.S.M.E. Norman C. Chen B.A. Felice P. Moody B.S. Walter McGregor M.B.A. John G. Thacker Ph.D. George T. Rodeheaver Ph.D. Richard F. Edlich M.D. Ph.D. 《The Journal of emergency medicine》1991,9(6):477-485
It is the purpose of this report to design, develop, and evaluate a needle holder whose jaws improve needle-holding security without altering the geometry of the curved surgical needle. The configuration of the jaws of this new needle holder is curved, conforming to the curvature of the surgical needle. A biomechanical study of this curved surgical needle holder demonstrates that it holds the curved needle securely without needle deformation. 相似文献
69.
70.
BACKGROUND: Controversy exists regarding the interpretation of diagnostic peritoneal lavage results. This is especially true in the evaluation of patients sustaining penetrating trauma, specifically stab wounds to the lower chest and abdomen. Ideally one wants to avoid missed injuries and minimize unnecessary operations. METHODS: This is a retrospective review of 195 patients sustaining stab wounds to the anterior lower chest and abdomen at Parkland Memorial Hospital between 1993 and 2005, looking at missed injuries and false positive rates using red cell counts of 100,000, 10,000, and the standard criteria for blunt trauma including >500 white blood cells (WBCs), amylase, and/or bile. RESULTS: The first analysis used >100,000 red blood cells (RBCs)/mm3 as a positive value. The false positive rate was 12.2%. The second analysis used >10,000 RBCs/mm3 as a positive value with a false positive rate of 44%. When considering the entire study population (195 patients), the false positive rate increased when using the lower number (>10,000) from 2.5% to 15.8% (p < 0.001). There were no missed injuries when using >100,000 red cells and/or >500 white cells, the presence of bile or amylase. CONCLUSION: Decreasing the red blood cell count from >100,000 to >10,000 as the criteria for operating on patients with stab wounds to the anterior lower chest and/or abdomen will significantly increase the number of nontherapeutic procedures. Based on this study, >100,000 RBCs/mm3 appears to be a valid and safe number to use when evaluating these patients, particularly when used with other positive criteria such as increased white cells, bile, and amylase. 相似文献