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21.
The bubble point test is the de facto standard for postproduction filter membrane integrity test in the radiopharmaceutical community. However, the bubble point test depends on a subjective visual assessment of bubbling rate that can be obscured by significant diffusive gas flows below the manufacturer's prescribed bubble point. To provide a more objective means to assess filter membrane integrity, this study evaluates the pressure-hold test as an alternative to the bubble point test. In our application of the pressure-hold test, the nonsterile side of the sterilizing filter is pressurized to 85% of the predetermined bubble point with nitrogen, the filter system is closed off from the pressurizing gas and the pressure is monitored over a prescribed time interval. The drop in pressure, which has a known relationship with diffusive gas flow, is used as a quantitative measure of membrane integrity. Characterization of the gas flow vs. pressure relationship of each filter/solution combination provides an objective and quantitative means for defining a critical value of pressure drop over which the membrane is indicated to be nonintegral. The method is applied to sterilizing filter integrity testing associated with the commonly produced radiopharmaceuticals, [18F]FDG and [11C]PIB. The method is shown to be robust, practical and amenable to automation in radiopharmaceutical manufacturing environments (e.g., hot cells).  相似文献   
22.
Thiazide diuretics may preserve bone mass and prevent elderly women's osteopenic fractures, but studies have not distinguished between thiazide preparations or examined former users. We performed a case-control study looking at thiazide use and subsequent hip fracture in postmenopausal female members of the Framingham Study cohort. Cases who had experienced a first hip fracture (n = 176) were compared with age-matched controls (n = 672). Results showed a modest protective effect of any recent thiazide use (not significant). However, recent pure thiazide users experienced significant protection against fracture (adjusted odds ratio, 0.31; 95% confidence interval, 0.11 to 0.88), whereas recent users of combination drugs containing thiazides experienced no protection (adjusted odds ratio, 1.16; 95% confidence interval, 0.44 to 3.05). Combination drugs generally contained only 25 mg of hydrochlorothiazide, suggesting that the small amount of thiazide was insufficient to preserve bone mass. Former thiazide users were not protected against fracture. In sum, recent pure thiazide use in women protects against hip fracture.  相似文献   
23.
ABSTRACT The claims made for the contribution of Evolutionary Psychology to psychotherapy are questioned. The relevance of human evolutionary history is not disputed, but it is argued that insufficient account is taken of the unique features of human beings, that the polemical attacks made on the social and human sciences are irrational, that the hypothetical reconstructions of human evolution are frequently arbitrary and biased, and that the extent to which evolved innate'mentalities'are said to determine social roles ignores the evidence for the plasticity of human brains and for social influences in individual development. In its consistent bias in favour of innate rather than learned and culturally formed processes and in its language and assumptions EP underestimates the inherited and acquired capacities of human societies and individuals to change. It fails to take adequate account of the key evolutionary development whereby humans became symbol-making and symbol-using social animals whose individual psychological development involves processes, the understanding of which requires a new theoretical perspective. These features, combined with the absence of a clear model of practice, seriously limit the contribution of EP to psychotherapy.  相似文献   
24.
OBJECTIVE: To assess the reliability of a nurse-performed nutrition screening tool (NST) for hemodialysis (HD) patients to identify nutritionally at-risk patients. DESIGN: Tool reliability assessment. SETTING AND PARTICIPANTS: The setting was nine non-hospital private (n = 3) and public (n = 6) HD units in Australia (two rural and seven metropolitan). Participants were 112 HD patients. RESULTS: A total of 112 HD patients (male = 65, female = 47) from 9 non-hospital HD units in Australia (seven metropolitan and two rural) were screened with the NST and the outcome of dietitian referral compared with Standard Dietitians Assessment. The mean age of patients was 57.6 years. Overall, the NST showed a sensitivity of 0.84 (range, 0.71 to 0.94; P < .05) and a specificity of 0.9 (range, 0.82 to 0.98; P < .05). The NST was more sensitive (sensitivity, 0.93 [range, 0.87 to 0.99; P < .05]) and was more specific for men (specificity, 0.92 [range, 0.85 to 0.99; P < .05]). Specificity was very strong in metropolitan patients (specificity, 0.94 [range, 0.87 to 1.01; P < .05]). CONCLUSIONS: The tool was more sensitive and specific than the NST previously reported by the same investigators. The tool is particularly specific in that it screens those patients not requiring dietitian intervention. The use of this tool may benefit HD units that do not have on-site or regular dietetic support to prioritize patients needing dietitian intervention.  相似文献   
25.
The assessment of the medical lethality and intent of suicide attempts has been considered an important area of research for those interested in suicide. The current study examined the usefulness of the Risk-Rescue Rating Scale with 109 adolescent suicide attempters and found a restricted range of variability, which, in turn, resulted in poor interrater reliability on a number of items. Results suggest that the Risk-Rescue Rating Scale is of limited usefulness with adolescents, and alternative approaches to assessing lethality and suicidal intent with this age group are discussed.  相似文献   
26.
PURPOSE: This study was designed to assess pelvic bone temperature during typical treatment regimens of transurethral ultrasound thermal ablation of the prostate to establish guidelines for limiting bone heating. METHODS: Treatment with transurethral planar, curvilinear, and sectored tubular applicators was simulated using an acoustic and biothermal pelvic model that accommodates applicator sweeping, boundary temperature control, and changes in perfusion and attenuation with thermal dose to more accurately model ultrasound energy penetration. The effects of various parameters including power and frequency (5-10 MHz) on bone heating were assessed for a range of prostate cross-sections (3-5 cm) and bone distances (1-3 cm). RESULTS: All devices can produce significant bone heating (temperatures >50 degrees C, thermal dose >240 EM(43 degrees C)) without optimization of applied frequency or power for bone <3 cm from the prostate boundary. In small glands ( approximately 3 cm) increasing operating frequency of curvilinear and planar devices can increase bone temperatures, whereas the tubular applicator can be used at 10 MHz to avoid likely bone damage. In larger prostates (4-5 cm wide) increasing frequency reduces bone heating but can substantially increase treatment time. Lowering power can reduce bone temperature but may increase thermal dose by increasing treatment duration. All applicators can be used to treat glands 4-5 cm with limited bone heating by selecting appropriate power and frequency. CONCLUSIONS: Pubic bone heating during ultrasound thermal therapy of the prostate can be substantial in certain situations. Successful realization of this therapy will require patient-specific treatment planning to optimally determine power and frequency in order to minimize bone heating.  相似文献   
27.
This is a retrospective review of the results at our institution of using multi-detector CT angiography (CTA) to localise lower gastrointestinal (GI) bleeding. We hypothesised that in our patient population: (i) CTA was unlikely to demonstrate bleeding in patients who were haemodynamically stable; (ii) in haemodynamically unstable patients in whom CTA was undertaken, the results could be used to select patients who would benefit from catheter angiography; and (iii) in haemodynamically unstable patients in whom CTA was undertaken, a subgroup of patients could be identified who would benefit from primary surgical treatment, avoiding invasive angiography completely. A retrospective review was conducted of the clinical records of all patients undergoing CTA for lower GI haemorrhage at our institution between 1 January 2005 and 30 June 2007. Out of the 20 patients examined, 10 had positive CTAs demonstrating the bleeding site. Nine were haemodynamically unstable at the time of the study. Four patients with positive CT angiograms were able to be treated directly with surgery and avoided invasive angiography. Ten patients had negative CTAs. Four of these were haemodynamically unstable, six haemodynamically stable. Only one required intervention to secure haemostasis, the rest stopped spontaneously. No haemodynamically stable patient who had a negative CTA required intervention. CTA is a useful non-invasive technique for localising the site of lower GI bleeding. In our patient population, in the absence of haemodynamic instability, the diagnostic yield of CTA was low and bleeding was likely to stop spontaneously. In haemodynamically unstable patients, a positive CTA allowed patients to be triaged to surgery or angiography, whereas there was a strong association between a negative CTA and spontaneous cessation of bleeding.  相似文献   
28.
29.
This analysis applies methods of screening to the problem of psychosis. A probability sample of 810 individuals from the Eastern Baltimore Mental Health Survey was interviewed in the self-report modality with the Diagnostic Interview Schedule and shortly thereafter by a psychiatrist. It is shown that a configuration of responses in the self-report modality can screen moderately well for psychosis, as measured by psychiatrists in the clinical modality.  相似文献   
30.
INTRODUCTION: This treatment-outcome assessment objectively compares Invisalign (Align Technology, Santa Clara, Calif) treatment with braces. METHODS: This study, a retrospective cohort analysis, was conducted in New York, NY, in 2004. Records from 2 groups of 48 patients (Invisalign and braces groups) were evaluated by using methods from the American Board of Orthodontics Phase III examination. The discrepancy index was used to analyze pretreatment records to control for initial severity of malocclusion. The objective grading system (OGS) was used to systematically grade posttreatment records. Statistical analyses evaluated treatment outcome, duration, and strengths and weaknesses of Invisalign compared with braces. RESULTS: The Invisalign group lost 13 OGS points more than the braces group on average, and the OGS passing rate for Invisalign was 27% lower than that for braces. Invisalign scores were consistently lower than braces scores for buccolingual inclination, occlusal contacts, occlusal relationships, and overjet. Invisalign's OGS scores were negatively correlated to initial overjet, occlusion, and buccal posterior crossibite. Invisalign patients finished 4 months sooner than those with fixed appliances on average. P < .05 was used to determine statistically significant differences. CONCLUSIONS: According to the OGS, Invisalign did not treat malocclusions as well as braces in this sample. Invisalign was especially deficient in its ability to correct large anteroposterior discrepancies and occlusal contacts. The strengths of Invisalign were its ability to close spaces and correct anterior rotations and marginal ridge heights. This study might help clinicians to determine which patients are best suited for Invisalign treatment.  相似文献   
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