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141.
JA Teresi RR Golden P Cross B Gurland M Kleinman D Wilder 《Canadian Metallurgical Quarterly》1995,48(4):473-483
A study of item bias in standard cognitive screening measures was conducted in a sample of Afro-American, Hispanic and non-Hispanic white elderly respondents who were part of a dementia case registry study. The methods of item-response theory were applied to identify biased items. Both cross-cultural and high and low education groups were examined to determine which items were biased. Out of 50 cognitive items examined from six widely used cognitive screening measures, 16 were identified as biased for either high and low education groups or ethnic/racial group membership. 相似文献
142.
B Elliott C Richardson J Winderbaum JA Nickoloff M Jasin 《Canadian Metallurgical Quarterly》1998,18(1):93-101
A new assay termed the dome disappearance method for classical swine fever virus (CSFV) using FS-L3 cells with serum-free culture medium was developed. The CSFV live vaccine GPE- strain grows well and shows a slight cytopathic effect (CPE) in FS-L3 cells. This CPE results in the disappearance of the unique fluid-filled multicellular domes on a single monolayer of FS-L3 cells. By using this phenomenon, dome disappearance, as a marker of infection, it was possible to determine the titers of CSFV and its neutralizing antibody. The virus titer determined by this method shows a good correlation with that determined by immunochemical and interference methods. Furthermore, the amount of neutralizing antibody measured by this method also correlated with that measured by the Exaltation of Newcastle Disease Virus (END) neutralizing method. The dome disappearance method developed in this experiment is a simple and safe procedure and has the great advantage that bovine serum, which may contain antibody against bovine viral diarrhea virus, is not necessary for the cultivation of FS-L3 cells. 相似文献
143.
BE Schreuder RE Geertsma LJ van Keulen JA van Asten P Enthoven RC Oberthür AA de Koeijer AD Osterhaus 《Canadian Metallurgical Quarterly》1998,142(18):474-480
The efficacy of the procedures in use at the two rendering plants in the Netherlands was assessed on a laboratory-scale using procedures that simulated the pressure cooking part of the rendering process. A pool of bovine spongiform encephalopathy (BSE)-infected brainstem from the United Kingdom and a pool of scrapie-infected brainstem from Dutch sheep were used to spike the rendering materials. The mixtures were subjected to various time-temperature combinations of hyperbaric heat treatment related to the conditions used in Dutch rendering plants in the early 1990s, and to the combination of 20 minutes at 133 degrees C required by the EU Directive on rendering of 1996. The efficacy of the procedures in inactivating BSE or scrapie infectivity was measured by titrating the materials before and after heat treatment in inbred mice, by combined intracerebral and intraperitoneal inoculations at limiting dilutions. Two independent series of experiments were carried out. The design of the study allowed for minimum inactivations of up to 2.2 log (2.0 in the second series) to be measured in the diluted infective material and 3.1 log in the undiluted material. After 20 minutes at 133 degrees C there was a reduction of BSE infectivity of about 2.2 log in the first series (with some residual infectivity detected), and in the second series more than 2.0 log (with no residual infectivity detected). With undiluted brain material there was an inactivation of about 3.0 log (with some residual infectivity detected). With the same procedure, scrapie infectivity was reduced by more than 1.7 log in the first series and by more than 2.2 log in the second series. With undiluted brain material there was an inactivation of more than 3.1 log. In each case no residual scrapie infectivity was detected. The BSE agent consistently appeared to be more resistant to heat inactivation procedures than the scrapie agent, particularly at lower temperatures and shorter times. 相似文献
144.
AIM: Assessment of the antihypertensive effect of doxazosin, alpha-1 blocker, as well as its action on lipid and carbohydrate metabolism, microcirculation and platelet function in patients with non-insulin-dependent diabetes mellitus (NIDDM). MATERIALS AND METHODS: Doxazosin (tonocardin) treatment was given for 11 weeks to 33 NIDDM patients with concomitant hypertension. The clinical examination comprised evaluation of central hemodynamics, vessels of the fundus of eye, lipid and carbohydrate metabolism, renal function, platelet aggregation. RESULTS: Tonocardin produced a fall in the systolic blood pressure (BP) by 14%, in the diastolic BP--by 17%. The 24-h profile of BP, lipid and purine metabolism, microcirculation of the vessels of the fundus of eye also improved. Total peripheral vascular resistance, left ventricular myocardial mass and platelet aggregation. Carbohydrate metabolism remained unchanged. CONCLUSION: Monotherapy with tonocardin (2-8 mg/day) is effective and safe in the treatment of arterial hypertension in NIDDM patients. 相似文献
145.
JC López Pacios L Parra Muntaner MC Pi?eiro Fernández SC Gómez Cisneros E Sánchez Sánchez JA Rivas Escudero FJ Madrid García J García Alonso 《Canadian Metallurgical Quarterly》1998,51(4):331-333
The occurrence of secondary hypogonadism is a common finding in males who seek help with erectile dysfunction, although the relationship to diminished testosterone is unclear. Two possibilities exist regarding both the genesis and maintenance of the hypogonadotropic hypogonadal state. First, a defect in hypothalamic function, resulting in downregulation as well as in alterations of anterior pituitary function; second, estradiol inhibition of gonadotropin release, both of which result in decreased testosterone production. As testosterone levels decrease and estradiol levels increase, the ratio of free testosterone to estradiol reaches a critical point and the estrogenic gonadotropin suppressive effects predominate. This ratio may signal the biological point of no return and could become one of the criteria for defining the separation of the transitional hypogonadal state from the final 'end stage' hypogonadotropic hypogonadal state. As the aging process continues, there is a relative accumulation of fatty tissue, and aromatization accelerates the conversion of testosterone to estradiol. This additional secondary estradiol inhibition results in the maintenance of the testosterone deficient state, and the aging process continues uncontested. 相似文献
146.
TS Bocanegra AL Weaver EA Tindall DH Sikes JA Ball CB Wallemark GS Geis JG Fort 《Canadian Metallurgical Quarterly》1998,25(8):1602-1611
147.
The SimPlate Total Plate Count (TPC) test, developed by IDEXX Laboratories, Inc., detects and quantitates total bacterial concentration in food after 24 h of incubation. The performance of SimPlate TPC was compared with that of the plate count agar (PCA) method for enumerating total bacterial concentration of 255 food samples representing 15 different food matrixes. Total bacterial counts on SimPlate TPC were measured after 24 h of incubation and plotted against values obtained from PCA after 48 h. Simple regression analysis of the data showed strong correlation between the methods (r = 0.95); the sensitivity of SimPlate TPC for foodborne bacteria was 96% relative to PCA (slope = 0.96). It was concluded that SimPlate TPC is a suitable alternative for the detection and quantitation of foodborne bacteria. The method has been granted Performance Tested Certification by the AOAC Research Institute. 相似文献
148.
149.
150.
PURPOSE: During radical prostatectomy for prostate cancer tumor at the surgical margin is a relatively frequent finding. We summarize the literature on the incidence, etiology, location, prevention and treatment of positive surgical margins after radical prostatectomy. MATERIALS AND METHODS: The literature was reviewed for data on positive margins during radical prostatectomy for prostate cancer. RESULTS: Positive surgical margins may result from artifacts induced by tissue processing, incising inadvertently into the prostate or incising into extraprostatic tumor that has extended beyond the limits of resection. Patients with 10 ng./ml. or greater preoperative prostate specific antigen, biopsy Gleason score 7, multiple positive biopsies, or clinical stage T2b, T2c or T3 cancer have a higher risk of positive margins. Preoperative endorectal magnetic resonance imaging may be useful in staging a select group of patients. Neoadjuvant androgen deprivation reduces the incidence of positive margins but does not appear to delay progression or improve survival. The surgical approach, retropubic or perineal, may influence the location and etiology of positive margins. In general, nerve and bladder neck sparing procedures do not compromise tumor removal in appropriately selected patients. Positive margins increase the risk of progression and correlate with decreased cancer specific and overall survival. There is no consensus on the management of positive margins. External beam radiation and androgen deprivation may be administered as adjuvant therapy or at the time of recurrence. CONCLUSIONS: Tumor at the specimen edge is an adverse prognostic factor. With appropriate patient selection and meticulous surgical technique some positive margins can be prevented. Controlled prospective randomized studies of postoperative therapy are needed before definitive recommendations can be made for treating positive margins. 相似文献