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21.
22.
人体前方不同位置目标点拾取运动时间特性的研究 总被引:1,自引:0,他引:1
目的 研究人体前方不同位置目标点的拾取运动时间特性,探讨拾取运动的起始点和目标点位置对拾取时间的影响.方法 设计并进行人体上肢拾取运动实验,记录拾取时间数据,通过数据分析,探讨人体上肢从平面板上不同起始点拾取前方不同位置目标点的运动时间特性.结果 分析结果表明,起始点和目标点的位置改变对拾取时间有极大影响.结论 右利手者拾取前方不同位置目标点时,目标点相对于起始点的方位不同,或起始点(目标圆)位置有变,都会造成拾取时间的显著差异.起始点在目标板上行方向的位置变化对拾取时间影响较大,在列方向的位置变化对拾取时间影响较小.对右利手者,当拾取距离一定时,从起始点向右上方45°目标点的拾取时间最短;起始点位于人体右侧时,该起始点所在目标圆总的拾取时间最短. 相似文献
23.
Krista Kupres DO Capt Usa MC Steven E. Rasmussen MD MAJ Usaf Fs MC John G. Albertini MD MAJ Usaf MC 《Dermatologic surgery》2002,28(5):388-389
BACKGROUND: Low cost, nonsterile examination gloves are used routinely to perform various dermatologic procedures. OBJECTIVE: To evaluate the perforation rate of nonsterile examination gloves in routine dermatologic procedures. METHODS: Three hundred fifty nonsterile latex examination gloves used to perform shave biopsies were evaluated for perforations using an air inflation/water submersion method. Ninety gloves, which were intentionally perforated with a 30-gauge needle, were used as controls to assess our evaluation method. RESULTS: Eight of the 350 gloves were found to have a perforation, which corresponds to a 2.3% perforation rate. Seven of the eight perforations were found in the web space between the second and third finger sleeves, with one being an obvious manufacturing error. All 90 perforations of the control group were correctly identified. CONCLUSION: There appears to be a very low risk of glove perforation when nonsterile examination gloves are used in routine dermatologic procedures. 相似文献
24.
Background Incidental thyroid abnormalities are increasingly detected in patients undergoing PET scans. The aim of this study was to
review our experience with the management of PET detected thyroid incidentalomas in a large single institution series.
Methods All PET scans performed from May 2003 to July 2005 were reviewed and patients with incidental thyroid abnormalities were identified.
From this group, patients that underwent further investigation were analyzed. Data relating to PET scan findings, FNA diagnoses,
operative details, and histopathology was reviewed.
Results In 8,800 patients, 16,300 PET scans were performed of whom 263 patients (2.9% of patients and 1.6% of PET scans) had findings
positive for thyroid abnormality. Thyroid malignancy was noted in 42% (24 patients) of the 57 patients that underwent FNA.
In the group of 27 patients that were subjected to operative intervention, 74% (20 patients) were noted to have a malignant
diagnosis. The final histopathology revealed primary thyroid carcinoma in all these 20 patients (19 patients with papillary
carcinoma and one patient with primary thyroid lymphoma). The factors that correlated with an increased risk of malignancy
were the presence of physical finding (p = 0.01) and focal (p < 0.01) or unilateral uptake (p < 0.01) on PET scan. The average SUV was not useful in differentiating benign (9.2) from malignant lesions (8.2, p = 0.7).
Conclusions PET detected incidental thyroid abnormalities are rare. In patients with positive PET scan findings and suspicious features,
the incidence of primary thyroid malignancy is very high. These patients warrant further investigation followed by possible
operative intervention. 相似文献
25.
Edward Avila DO Paul Schraeder MD Ajit Belliappa MD Scott Faro MD 《Journal of neuroimaging》2006,16(1):78-81
This is a case report of central nervous system toxicity associated with paradichlorobenzene (PDCB) ingestion. The patient had ingested mothballs composed of 99.99% PDCB for a period of 7 months. She was admitted for depression and had no neurologic symptoms. Later she developed an acute cerebellar syndrome followed by stupor and coma. An extensive workup was negative except for decreasing levels of PDCB in her serum. Imaging revealed a diffuse leukoencephalopathy. Her clinical picture was attributed to PDCB toxicity. 相似文献
26.
Fibromyalgia is a syndrome of widespread pain, nonrestorative sleep, disturbed mood, and fatigue. Optimal treatment involves
a multidisciplinary approach with a team of health care providers using pharmacologic and nonpharmacologic treatment. Because
of the heterogeneity of the illness, management should be individualized for the patient. Pharmacologic treatment should address
issues of pain control, sleep disturbance, fatigue, and any underlying coexisting mood disorder. Nonpharmacologic treatment
should include patient education, a regular exercise and stretching program, and cognitive behavioral therapy. All of these
are essential to improving functional capacity and quality of life. This review provides general guidelines in initiating
a successful pharmacologic treatment program for patients with fibromyalgia. 相似文献
27.
Claude C. Frazier PhD DO Ana P. Camacho MD Clay J. Cockerell MD 《Dermatologic surgery》2001,27(5):489-492
BACKGROUND: Eruptive syringomas are uncommon benign adnexal neoplasms. They are numerous and disseminated and often have a predilection for the neck, face, chest, and axillary fossae. Because they are persistent, usually numerous, and often on exposed sites, the lesions may be disfiguring and often pose significant cosmetic concerns for patients. Many treatment modalities such as dermabrasion, electrodesiccation with curettage, and scissors excision have been tried with some success, but more recently lasers have provided good to excellent results. OBJECTIVE: To describe an approach to the treatment of eruptive syringomas in an African American patient with a combination of trichloroacetic acid (TCA) and CO2 laser resurfacing, providing acceptable cosmetic results without significant side effects. METHODS: We describe an African American patient with eruptive syringomas of the face treated with a combination of TCA and CO2 laser resurfacing with good results. RESULTS: While the syringomas were not completely ablated, the combination of TCA and CO2 laser resurfacing provided acceptable cosmetic results without significant side effects. CONCLUSION: The TCA pretreatment probably removed some of the bulk of the surface of the lesions, thereby reducing the number of laser passes required to flatten the remainder of the lesions and thus lessening the potential for thermal damage at the treated sites and of surrounding normal skin. 相似文献
28.
EDWARD VICTOR ROSS MD NATHAN S. UEBELHOER DO YACOV DOMANKEVITZ PHD 《Dermatologic surgery》2007,33(12):1466-1469
BACKGROUND Purpura-free elimination of telangiectases with a single pass of a pulsed dye laser with a large spot has proved difficult.
OBJECTIVE The purpose of this report was to define parameters that achieve single-pass purpura-free telangiectasia reduction.
MATERIALS Thirty patients between the ages of 23 and 78 years were treated with a pulsed dye laser with a 10-mm spot and fluences ranging from 9 to 10 J/cm2 . The macropulse width was 20 ms. Each macropulse was composed of eight pulselets. Treatments were carried out over facial areas with discrete telangiectases.
RESULTS Smaller telangiectases (<600 μm) showed transient bluing followed by stenosis. Larger vessels (600–10,000 μm) showed bluing but inconsistent closure. A second pass typically resulted in closure.
CONCLUSION A modified pulsed dye laser was capable of single-pass purpura-free reduction with a 10-mm spot size. 相似文献
OBJECTIVE The purpose of this report was to define parameters that achieve single-pass purpura-free telangiectasia reduction.
MATERIALS Thirty patients between the ages of 23 and 78 years were treated with a pulsed dye laser with a 10-mm spot and fluences ranging from 9 to 10 J/cm
RESULTS Smaller telangiectases (<600 μm) showed transient bluing followed by stenosis. Larger vessels (600–10,000 μm) showed bluing but inconsistent closure. A second pass typically resulted in closure.
CONCLUSION A modified pulsed dye laser was capable of single-pass purpura-free reduction with a 10-mm spot size. 相似文献
29.
Posy Seifert DO David Conover MS Yan Zhang PhD Renee Morgan R.T. Andrea Arieno BS Stamatia Destounis MD Patricia Somerville MD Philip F. Murphy MD 《The breast journal》2014,20(4):364-374
To investigate the feasibility of noncontrast and contrast‐enhanced cone beam breast Computed Tomography (CT) in demonstrating malignant breast lesions in the diagnostic setting. This Institutional Review Board approved, Health Information Portability and Accountability Act compliant, prospective study enrolled BI‐RADS four and five patients from 2008 to 2010. Eighty‐seven subjects had noncontrast breast CT, 42 had contrast‐enhanced breast CT (CE‐breast CT) with 70 pathologically confirmed cancer diagnoses. All 70 comprise the study cohort for noncontrast breast CT, and 23 who had CE‐breast CT comprise the cohort for CE‐breast CT. All had diagnostic work‐up. Patient age, breast density, lesion size and characteristics, biopsy method, and core pathology were recorded. A Fisher's exact test was used to detect a difference in detectability. For agreement in size measurement between the imaging modalities, a paired t‐test was employed. Reported p‐values were based on 2‐sided tests. Two one‐sided tests were calculated to determine equivalence within ±0.3 cm at a 90% significance level. Noncontrast breast CT identified 67 of 70 malignant lesions, detected by diagnostic work‐up. CE‐breast CT identified 23 of 23 index malignant lesions and in addition, found three malignant lesions in three cases not previously detected. Noncontrast breast CT demonstrated the index lesion in 67 of 70 cases and CE‐breast CT demonstrated the index lesion in all 23 cases. An additional three new malignant lesions not seen with conventional diagnostic work‐up were detected. In this preliminary study, breast CT with or without contrast was shown to be accurate at identifying malignant breast lesions in the diagnostic setting. 相似文献
30.
Wesley A. Papenfuss MD FACS Moshim Kukar MD Jacqueline Oxenberg DO Kristopher Attwood MA PhD Steven Nurkin MD MS Usha Malhotra MD Neal W. Wilkinson MD FACS 《Annals of surgical oncology》2014,21(9):3008-3014