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101.
102.
Many techniques of magnetic resonance angiography depend on flow velocity. The broad normal range of venous flow velocities and preferential patterns of drainage, particularly in the transverse sinuses, may produce images that are diagnostically misleading. This reports such a case, with samples of various flow patterns in the transverse sinuses of other individuals, as demonstrated by one magnetic resonance angiographic technique (time-of-flight). 相似文献
103.
104.
Thomas R Flynn Rabie M Shanti Catherine Hayes 《Journal of oral and maxillofacial surgery》2006,64(7):1104-1113
PURPOSE: The purpose of this study was to identify significant predictors of 4 outcomes in patients with severe odontogenic infections: abscess formation, penicillin therapeutic failure (PTF), length of hospital stay (LOS), and need for reoperation. PATIENTS AND METHODS: We used a prospective case series study design and enrolled 37 consecutive patients admitted for severe odontogenic infection between March 1996 and June 1999. Treatment consisted of intravenous penicillin (PCN) or clindamycin in PCN-allergic patients, surgical incision and drainage, and extraction(s) as soon as possible. Study variables were categorized as demographic, preadmission, time-related, preoperative, anatomic, treatment, microbiologic, and complications. The primary outcome variables were abscess formation, PTF, LOS, and reoperation. Multivariate linear and logistic regression techniques were used to measure associations between study variables and the outcome variables. RESULTS: The sample consisted of 37 subjects (23 male, 14 female) with a mean age of 34.9 +/- 15.8 years. Multivariate analyses, controlling for confounding variables, indicated that culture of Peptostreptococci was a negative predictor of abscess formation. LOS was predicted by the number of infected spaces and duration of operation. There was no significant predictor of PTF or reoperation on multivariate analysis, although PCN-resistant organisms were isolated in all cases of PTF. CONCLUSION: Increased LOS in severe odontogenic infections is predicted by the anatomic extent and severity of the infection and the occurrence of complications such as PTF and the need for reoperation. PTF is significantly associated with later identification of PCN-resistant organisms. The role of Peptostreptococci in abscess formation warrants further investigation. 相似文献
105.
Catherine L. Gilliss 《Journal of nursing scholarship》1991,23(1):19-22
The absence of critical dialogue regarding what constitutes family nursing prevents the further development of the specialty area of family nursing. In this essay, the author issues nine challenges faced by those who would contribute to the development of family nursing. 相似文献
106.
Anthony H Harris Richard H Osborne Catherine L Streeton Helen McNeil 《Supportive care in cancer》2002,10(6):486-493
The goal of this work was to investigate preference techniques to value potential health gains from treatments of Kaposi sarcoma (KS). The study was designed to take the form of face-to-face interviews with a sample of men with a history of HIV/AIDS ( n=15) or HIV/AIDS and KS ( n=17). The main outcome measure was quality of life (QoL) associated with various KS disease states expressed on a scale from 0 (death) to 1 (perfect health), obtained though time trade-off (TTO) and rating scale techniques. For cutaneous lesions only, the mean TTO preference score value was 0.27. In other words, the men were willing to trade a life expectancy of 5 years for a shorter period (1.4 years) in perfect health. More severe KS health states were rated lower (0.07-0.09). The mean rating scale value for cutaneous lesions only was 0.11 and ranged from -0.10 to -0.04 for the more severe conditions; these values were systematically lower than the TTO ( P=0.014). A large overall potential gain in QoL from treatment (partial response minus stable disease) was found for each condition to be reflected in both the TTO (from 0.31 to 0.55) and the rating scale (from 0.38 to 0.44). Respondents associate KS health states with extremely poor QoL and indicate that large gains are possible through modest treatment effects. While TTO returns higher values than the rating scale, potential gains from treatments were similar. The techniques appear to be suitable for application to QoL and economic evaluation of treatments of KS. 相似文献
107.
Blinded clinical evaluation of positron emission tomography for diagnosis of probable Alzheimer's disease. 总被引:5,自引:0,他引:5
W J Powers J S Perlmutter T O Videen P Herscovitch L K Griffeth H D Royal B A Siegel J C Morris L Berg 《Neurology》1992,42(4):765-770
We evaluated the sensitivity and specificity of positron emission tomography for diagnosis of probable Alzheimer's disease under conditions similar to those encountered in the routine clinical practice of nuclear medicine. We obtained tomographic images of regional cerebral blood flow from three groups of subjects: (1) 13 subjects, ages 69 to 84, who had probable Alzheimer's disease diagnosed by validated clinical criteria; (2) 15 subjects, ages 57 to 77, who had Parkinson's disease without dementia; and (3) 11 subjects, ages 65 to 83, who were normal. Three blinded reviewers, who had not previously seen the images, categorized them as normal, bilateral temporoparietal flow defects typical of Alzheimer's disease, or other abnormality. Consensus interpretation demonstrated sensitivity of 0.38 (5/13) and specificity of 0.88 (23/26) for identifying patients with probable Alzheimer's disease. Thus, the criterion of bilateral temporoparietal reduction in cerebral blood flow used in this study did not have sufficient sensitivity to be of clinical value. While other criteria may be developed to improve diagnostic accuracy, clinical utility can be established only by testing for validity in patients with a full spectrum of complicating neurologic and psychiatric conditions for whom diagnosis is uncertain and who are then followed longitudinally to determine clinical outcome or pathologic findings. 相似文献
108.
585-nm Pulsed Dye Laser in the Treatment of Surgical Scars Starting on the Suture Removal Day 总被引:2,自引:0,他引:2
Keyvan Nouri MD Gloria P. Jimenez MD Catherine Harrison-Balestra BA George W. Elgart MD 《Dermatologic surgery》2003,29(1):65-73
BACKGROUND: The optimal time frame to improve the quality and cosmetic appearance of scars by laser therapy has not been clearly elucidated by prior controlled clinical trials. OBJECTIVE: To determine the efficacy of the 585-nm pulsed dye laser (PDL) in the treatment of surgical scars starting on the day of suture removal. METHODS: Eleven patients (skin types I-IV) with 12 postoperative linear scars that were greater than 2 cm were treated three times on monthly intervals with the 585-nm PDL (450 micro s, 10-mm spot size, 3.5 J/cm2 with 10% overlap) on one scar half, whereas the other half received no treatment. Scars were later evaluated by a blinded examiner using the Vancouver Scar Scale (VSS) for pigmentation, vascularity, pliability, and height. Scars were then blindly examined for cosmetic appearance using a visual analog scale. RESULTS: One month after the last treatment, final scar analysis by the blinded examiner revealed a significant difference between treated and untreated sites, with the treated halves scoring better in all scar parameters in the VSS and in cosmetic appearance. The treated halves demonstrated an overall average improvement in the VSS between the first treatment score and the final score of 54% versus 10% in the controls (P=0.0002). The cosmetic appearance score (0=worst; 10=best) at final assessment was significantly better for the treated scars, scoring 7.3 versus the averaged control score of 5.2 (P=0.016). CONCLUSION: The 585-nm PDL is effective and safe in improving the quality and cosmetic appearance of surgical scars in skin types I-IV starting on the day of suture removal. 相似文献
109.
DL-2-amino-4-phosphonobutyric acid does not eliminate "ON" responses in the visual system of goldfish. 下载免费PDF全文
P J DeMarco Jr J Bilotta M K Powers 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(9):3787-3791
DL-2-Amino-4-phosphonobutyric acid (APB) suppresses activity in retinal ON pathways. It is generally assumed that loss of the ON pathway would result in loss of ON responses in the visual system. We tested this assumption by recording activity from the optic nerves of intact goldfish (Carassius auratus) before and after intraocular injection of APB. Whole-nerve responses to increments and decrements of light were compared to electroretinogram responses and to tectal evoked potentials. APB severely reduced the amplitude of the electroretinogram b-wave but left ON and OFF responses from the optic nerve and tectum intact, although decreased in sensitivity. We conclude that APB does not completely eliminate ON responses in the visual system, at least in goldfish. The selectivity and effectiveness of APB must be evaluated in other species before this agent can be relied upon as a useful tool in understanding the roles of ON and OFF pathways in visual function. 相似文献
110.
A comparison of contraceptive use in the early to mid-1980s among married Puerto Rican women aged 15-49 in the New York City area reveals that island-born Puerto Rican women living in New York rely on female sterilization to nearly the same extent as do women living in Puerto Rico (45% and 41%, respectively) and that mainland-born Puerto Rican women use sterilization as much as do all women in the United States (19% for both groups). Puerto Rican women in New York use reversible methods to a greater extent than do women in Puerto Rico (22% v. 16%), but to a lesser extent than do all women in the United States (37%). Although mainland-born Puerto Rican women in New York use reversible methods more than do island-born women in New York (42% v. 23%), they tend not to adopt these methods to the same extent as do all U.S. women during the early reproductive years, when education and employment are critical to socioeconomic attainment. 相似文献