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111.
L. Alhilali S.-h. Seo B.F. Branstetter IV S. Fakhran 《AJNR. American journal of neuroradiology》2014,35(2):386
BACKGROUND AND PURPOSE:Globus sensation is common and difficult to treat. The purpose of our study was to compare the diagnostic and therapeutic efficacy of barium esophagram and neck CT in patients with isolated globus sensation, to determine which of these modalities should be preferred in the evaluation of this condition.MATERIALS AND METHODS:We retrospectively identified patients presenting with isolated globus sensation from January 1, 2005, to December 31, 2012, who underwent neck CT or barium esophagram. We calculated the proportion of patients with abnormal findings, tabulated the nature of the abnormality, and reviewed the medical records to determine whether imaging changed management.RESULTS:One hundred forty-eight neck CTs and 104 barium esophagrams were included. Five (3.4%) patients with neck CTs and 4 (3.9%) with barium esophagrams demonstrated significant findings related to the history of globus sensation. Of these, 1 (0.7%) neck CT and 1 (1.0%) barium esophagram resulted in a change in clinical management.CONCLUSIONS:Imaging evaluation of the patient with uncomplicated globus sensation is unlikely to identify clinically significant imaging findings and is very unlikely to result in a change in clinical management, with a combined therapeutic efficacy of 0.8%. Thus, the routine use of imaging in the evaluation of patients with globus sensation cannot be recommended.Globus sensation (GS), an intermittent or persistent painless sensation of a foreign body or lump in the throat, is a long-lasting and often frustratingly difficult-to-treat clinical entity.1 It is a relatively common condition, accounting for up to 4% of new referrals to otolaryngology clinics, with a prevalence of up to 35% in males and over 50% in females, with a relative peak in middle age.2–4 A range of etiologies has been suggested and described, including lingual and tonsillar hypertrophy, psychogenic factors, cervical osteophytes, upper aerodigestive tract malignancy, thyroid disease, and esophageal motor disorders.5–8 More recently, there has been increasing focus on gastroesophageal reflux disease as a cause of GS.9–13 The myriad potential etiologies of GS have made it difficult to establish standard treatment and imaging strategies for affected patients.The imaging approach to the patient with GS varies widely in clinical practice. A neck CT, usually ordered with contrast, is well-suited to detect many structural causes of GS and is a useful tool to exclude a large upper aerodigestive tract malignancy, while a barium esophagram is well-suited for detailed evaluation of esophageal motility and mucosal and submucosal lesions of the esophagus. While a barium esophagram may also detect (but cannot exclude) intermittent esophageal reflux, if evaluation for esophageal reflux is of primary concern, then esophageal manometry, endoscopy, esophageal pH monitoring, or a trial of empiric therapy is the preferred diagnostic test.14–16The imaging approach to the patient with GS varies widely in clinical practice. Because an evidence-based approach to imaging GS is lacking in current clinical practice, practitioner and locoregional biases strongly influence the decision to use neck CT or barium esophagram. This may adversely impact the clinical value of these studies because the value of a diagnostic test is largely dependent on the prevalence (or the clinician''s estimate of the pretest probability) of the target disorder, and abnormalities detectable on neck CT and barium esophagram are statistically unlikely etiologies in a general sample of patients with GS. Because overuse of diagnostic tests contributes to both the rising cost and the overall quality of health care, defining the value of diagnostic tests has become an important goal of health care reform. We conducted the present study to determine the incidence and nature of abnormalities on neck CT and barium esophagram examinations performed in the work-up of patients with isolated GS and to assess which imaging technique contributed most effectively to the clinical management of these patients. 相似文献
112.
Albert W. Pearsall IV M.D. J. Marcus Hollis Ph.D. George V. Russell Jr M.D. Zachary Scheer B.S. 《Arthroscopy》2003,19(10):1091-1096
Purpose: The purpose of this investigation was to evaluate 3 previously unreported allograft tendons for use in knee surgery. These are the doubled tibialis anterior (TA), doubled tibialis posterior (TP), and doubled peroneus longus (PL) tendons. Type of Study: A biomechanical evaluation of the properties of the TA, TP, and PL. Methods: Sixteen fresh-frozen cadaveric lower limbs were used for testing. All specimens had the TA, TP, and PL tendons harvested. All specimens were tested in a custom-designed hydraulic testing machine using dry ice clamps. Each tendon was elongated at a rate of 1 mm/s. Load and displacement were recorded with an analog to digital interface board. Stiffness, modulus of elasticity, and stress and strain at failure were calculated. Results: The average tested lengths of the TA, TP, and PL were 37 cm (range, 13–68 cm), 33 cm (range, 7–74 cm), and 42 cm (range, 17–69 cm), respectively. The average cross-sectional areas of the doubled TA, TP, and PL were 38 mm2, 48 mm2, and 37 mm2, respectively. The average failure loads for the doubled TA, TP, and PL tendons were 3,412 N, 3,391 N, and 2,483 N, respectively. The maximum stresses of the 3 tendons did not differ significantly (85–108 Mpa). The TA had the greatest stiffness (344 N/mm), followed by the TP (302 N/mm) and the PL (244 N/mm). Previous authors have documented the biomechanical strength of grafts for ACL reconstruction between 1,700 and 2,900 Newtons. The ultimate tensile strength and stiffness reported for the TA and TP grafts exceeded that for all previously reported grafts, including the doubled semitendinosus-gracilis. Conclusions: The TA, TP, and PL tendons showed excellent biomechanical properties when compared with historical data evaluating other graft sources. The biomechanical properties observed for the TA, TP, and PL were noted in specimens despite an average age of 78.3 years. 相似文献
113.
Ponnila S Samuel Jane P Pringle Nathaniel W James IV Susan J Fielding Kathleen M Fairfield 《International journal for equity in health》2009,8(1):30-5
Introduction
Minority women, particularly immigrants, have lower cancer screening rates than Caucasian women, but little else is known about cancer screening among immigrant women. Our objective was to assess breast, cervical, and colorectal cancer screening rates among immigrant women from Cambodia, Somalia, and Vietnam and explore screening barriers.Methods
We measured screening rates by systematic chart review (N = 100) and qualitatively explored screening barriers via face-to-face questionnaire (N = 15) of women aged 50–75 from Cambodia, Somalia, and Vietnam attending a general medicine clinic (Portland, Maine, USA).Results
Chart Review – Somali women were at higher risk of being unscreened for breast, cervical, and colorectal cancer compared with Cambodian and Vietnamese women. A longer period of US residency was associated with being screened for colorectal cancer. We observed a 7% (OR 1.07, 95% CI 1.01–1.13, p = 0.01) increase in the odds that a woman would undergo a fecal occult blood test for each additional year in the US, and a 39% increase in the odds of a woman being screened by colonoscopy or flexible sigmoidoscopy for every five years of additional US residence (OR 1.39, 95% CI 1.21–1.61, p = 0.02). We did not observe statistically significant relationships between odds of being screened by mammography, clinical breast exam or papanicolaou test according to years in the US. Questionnaire – We identified several barriers to breast, cervical, and colorectal cancer screening, including discomfort with exams conducted by male physicians.Discussion
Somali women were less likely to be screened for breast, cervical, and colorectal cancer than Cambodian and Vietnamese women in this population, and uptake of colorectal cancer screening is associated with years of residency in this country. Future efforts to improve equity in cancer screening among immigrants may require both provider and community education. 相似文献114.
REEL JERRY R.; TYL ROCHELLE W.; LAWTON A. DAVIS; LAMB JAMES C. IV 《Toxicological sciences》1992,18(4):609-615
Sulfamethazine (SMZ) was evaluated for reproductive toxicityin Swiss CD-1 mice using a continuous breeding protocol. SMZwas administered in the diet at 0, 0.25, 0.5, or 1% (w/w), whichrepresented an average daily intake of 0, 313, 625, or 1250mg SMZ/kg/day, respectively. Exposure of F0 male and femalemice to 1% SMZ for 126 days resulted in a significant decreasein the mean number of live pups per litter and the number oflitters produced (task 2); the percentage pups born alive to1% SMZ females showed a nonsignificant decrease versus controlfemales. The effects on fertility were rapid to onset (1 to4 weeks) and cumulative in nature. F0 male and female body weightswere slightly depressed from 3 weeks to the end of the study.The crossover mating trial (task 3) revealed that the adverseeffect on ferility involved both treated partners in that littersize decreased when either 1% SMZ males were bred to controlfemales or 1% SMZ females were mated with control males. Afterapproximately 155 days of exposure of F0 mice to 1% SMZ, theterminal body weight of 1% SMZ females was significantly decreasedand that of 1% SMZ males showed a nonsignificant decrease. Inaddition, the liver weight to body weight ratio of the maleswas increased. Further, the prostate and seminal vesicle weightto body weight ratios were decreased in 1% SMZ males relativeto control males. No treatment-related gross or histopathologicallesions were noted for the pituitary or reproductive organsof either sex. Sperm assessment indicated no significant differencein the epididymal sperm concentration or percentage motile orabnormal sperm. In conclusion, SMZ was found to be a reproductivetoxicant in the male and female Swiss CD-1 mouse, albeit atrelatively high dietary intake (1250 mg/kg/day), and in thepresence of mild systemic toxicity. 相似文献
115.
Complex three-dimensional (3-D) heart structure is an important determinant of cardiac electrical and mechanical function. In this study, we set to develop a versatile tissue-engineered system that can promote important aspects of cardiac functional maturation and reproduce variations in myofiber directions present in native ventricular epicardium. We cultured neonatal rat cardiomyocytes within a 3-D hydrogel environment using microfabricated elastomeric molds with hexagonal posts. By varying individual post orientations along the directions derived from diffusion tensor magnetic resonance imaging (DTMRI) maps of human ventricle, we created large (2.5 × 2.5 cm2) 3-D cardiac tissue patches with cardiomyocyte alignment that replicated human epicardial fiber orientations. After 3 weeks of culture, the advanced structural and functional maturation of the engineered 3-D cardiac tissues compared to age-matched 2-D monolayers was evident from: 1) the presence of dense, aligned and electromechanically-coupled cardiomyocytes, quiescent fibroblasts, and interspersed capillary-like structures, 2) action potential propagation with near-adult conduction velocity and directional dependence on local cardiomyocyte orientation, and 3) robust formation of T-tubules aligned with Z-disks, co-localization of L-type Ca2+ channels and ryanodine receptors, and accelerated Ca2+ transient kinetics. This biomimetic tissue-engineered platform can enable systematic in vitro studies of cardiac structure–function relationships and promote the development of advanced tissue engineering strategies for cardiac repair and regeneration. 相似文献
116.
NS Thompson MD FRCS R Date FRCS AP Charlwood FRCS IV Adair FRCS WDB Clements MD FRCS 《International journal of clinical practice》2001,55(8):573-575
This report describes a complex syndrome of injuries occurring in a young female who was a back seat passenger wearing a lap-belt restraint in a high-speed road traffic accident. As a consequence of the forced flexion distraction injury of her lumbar spine, she sustained a fracture-subluxation of the first lumbar vertebra in association with a jejunal perforation and extensive small intestinal mesenteric laceration. She also had a large traumatic hernia of the anterior abdominal wall, which was overlooked at primary laparotomy. This report highlights collectively the classical combination of injuries associated with the lap-belt syndrome and demonstrates the importance of carefully inspecting the anterior abdominal wall for deficiencies, because traumatic herniation may be easily overlooked. 相似文献
117.
Incidence rates of major transfusion transmissible viral infections have been estimated through widely used seroconversion approaches and recently developed methods.A quality database for blood donors and donations with the capacity to track donation history of each donor is the basis for incidence estimation and many other epidemiological studies.Depending on available data,different ways have been used to determine incidence rates based on conversion from uninfected to infected status among repeat donors.Reports of incidence estimates need to clearly describe specific ways that are used to derive such estimates so that readers can take into account any methodological differences that may exist when they compare incidence estimates from different studies.The recently developed methods,including the sensitive/less sensitive testing strategy for HIV,the NAT yield method and the HBsAg yield method as well as the prevalence-based approaches,are alternative options for estimating incidence,especially in donor populations where seroconversion approaches are not feasible.Their applicability needs to be examined before their use and results derived from these methods need to be reviewed with their assumptions and potential limitations in mind. 相似文献
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