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991.
992.
Restriction digest profiling of pneumococcal pbp2b-specific amplicons was effective for screening penicillin resistance. The pbp2b amplicon of all pneumococcal isolates for which the MICs of penicillin were < or = 0.03 microgram/ml had one of two different susceptible restriction profiles, and all 33 isolates for which MICs were 0.5 microgram/ml or greater had one of seven distinct resistant profiles. Low-concentration penicillin resistance (MICs = 0.06 microgram/ml to 0.25 microgram/ml) was associated with sensitive HaeIII profiles in some isolates; however, RsaI profiling and pbp2b sequence analysis of such isolates revealed that some isolates contained low-level resistant pbp2b alleles, while others had susceptible pbp2b alleles. This data indicates that low-level penicillin resistance is sometimes conferred by determinants other than pbp2b. 相似文献
993.
SK Grebe RR Cooke HC Ford JN Fagerstr?m DP Cordwell NA Lever GL Purdie CM Feek 《Canadian Metallurgical Quarterly》1997,82(3):870-875
We compared daily T4 therapy with 7 times the normal daily dose administered once weekly in 12 hypothyroid subjects in a randomized cross-over trial. At the end of each treatment we measured serum free T4 (FT4), free T3 (FT3), rT3, and TSH levels and multiple markers of thyroid hormone effects at the tissue level repeatedly for 24 h. Compared with daily administration, the mean serum TSH before the administration of weekly T4 was higher (weekly, 6.61; daily, 3.92 microIU/mL; P < 0.0001), and the mean FT4 (weekly, 0.98; daily, 1.35 ng/dL; P < 0.01) and FT3 (weekly, 208, daily, 242 pg/dL; P < 0.01) were lower. A minimally elevated serum total cholesterol during weekly administration (weekly, 246.8; daily, 232.6 mg/dL; P < 0.03) was the only evidence of hypothyroidism at the tissue level. Compared with daily administration, the mean peak FT4 following weekly administration of T4 was significantly higher (weekly, 2.71; daily, 1.59 ng/dL; P < 0.0001), as was the mean peak FT3 level (weekly, 285; daily, 246 pg/dL; P < 0.01). None of the tissue markers of thyroid hormone effect changed compared to daily T4, and there was no evidence of treatment toxicity, including cardiac toxicity. During weekly T4 administration, autoregulatory mechanisms maintain near-euthyroidism. For complete biochemical euthyroidism a slightly larger dose than 7 times the normal daily dose may be required. 相似文献
994.
This study utilizes a unique method to examine reports of stressful life events provided by eating disordered and non-eating disordered adolescents. Subjects (all females) participated in a standardized procedure to obtain reports of stressful life events. The Life Events and Coping Inventory (LECI) was used to categorize reported stressors. Eating disorder subjects discussed more stressors than non-eating disorder subjects only when eating disorder events were included. Furthermore, eating disorder subjects reported more events that could not be classified within the LECI and were rated as non-normative. The findings point to the importance of qualitative rather than purely quantitative approaches to stressful life events assessment with adolescents. 相似文献
995.
996.
CS Beckwith CL Franklin RR Hook CL Besch-Williford LK Riley 《Canadian Metallurgical Quarterly》1997,35(6):1620-1623
A fecal PCR assay for detection of Helicobacter infections in laboratory rodents was developed. DNA was isolated from murine fecal pellets, and a region of the 16S rRNA gene conserved among murine Helicobacter species was amplified. The fecal PCR was sensitive and specific. This assay does not require euthanasia of rodents, which is especially important for valuable rodents, such as transgenic mice. 相似文献
997.
Three new titanium alloys with Zr, Nb, Ta, Pd and In as alloying elements were developed and compared with currently used implant metals, namely, pure Ti and Ti-6Al-4V alloy, in terms of mechanical and corrosion properties, and cytotoxicity. New alloys showed comparable mechanical properties with that of the Ti-6Al-4V alloy, but increased corrosion potential, somewhat decreased breakdown potential and increased corrosion rate. There were no significant differences in cell growth on the surface of the various metal specimens, indicating that the cells cannot differentiate between the passivated surfaces of the various Ti metals. 相似文献
998.
TA Ignatowski BK Noble JR Wright JL Gorfien RR Heffner RN Spengler 《Canadian Metallurgical Quarterly》1997,79(1):84-90
Because of its wide variety of symptoms, the neurovascular compression syndrome of the upper thoracic aperture or thoracic outlet syndrome (TOS) has to be distinguished from several differential diagnoses, especially orthopedic ones. It is mainly characterized by pressure lesion of the brachial plexus and secondly, by accompanying vascular damages. An indication for surgery exists in cases of persisting or increasing complaints or function loss of shoulder, arm or hand muscles as well as in cases with occurrence of vascular damage. The treatment of choice consists of transaxillary resection of the first rib. This report presents a record of our results after transaxillary surgery and compares them to the results given in current international literature. During the last few years 3031 cases of transaxillary resections (13-473 cases) were described in international literature. The average follow-up period was 7.8 years (2-22 years). The results were good in 81.4% (50-93%) of the cases. From 02/80 to 03/94, we treated 67 patients with altogether 80 thoracic outlet syndromes (TOS). Each of them was treated similarly with extensive transaxillary resection of the first rib, excision of fibrous bands and, if necessary, of cervical ribs. Our results after surgery (84.5% of complete resolution or improvement of symptoms) compare favorably to those given by other authors. The average follow-up period was 6.6 years (0.5-14 years). Our results confirm, that transaxillary resection of the first rib is the method of choice in the treatment of thoracic outlet syndromes. 相似文献
999.
KL Jang RR McCrae A Angleitner R Riemann WJ Livesley 《Canadian Metallurgical Quarterly》1998,74(6):1556-1565
The common variance among personality traits can be summarized in the factors of the five-factor model, which are known to be heritable. This study examined heritability of the residual specific variance in facet-level traits from the Revised NEO Personality Inventory. Analyses of raw and residual facet scales across Canadian (183 monozygotic [MZ] and 175 dizogotic [DZ] pairs) and German (435 MZ and 205 DZ pairs) twin samples showed genetic and environmental influences of the same type and magnitude across the 2 samples for most facets. Additive genetic effects accounted for 25% to 65% of the reliable specific variance. Results provide strong support for hierarchical models of personality that posit a large number of narrow traits in addition to a few broader trait factors or domains. Facet-level traits are not simply exemplars of the broad factors they define; they are discrete constructs with their own heritable and thus biological basis. 相似文献
1000.
PURPOSE: We examine the clinical prognostic value of the currently available simple and inexpensive immunoenzymatic prostatic acid phosphatase (PAP) assay for the staging and prognosis of radical prostatectomy cases. MATERIALS AND METHODS: Between February 1, 1990 and May 3, 1996 pretreatment PAP was measured in 295 patients who underwent radical prostatectomy. From February 1, 1990 to May 17, 1992 the Hybritech Tandem-E assay was used in 75 cases, from May 18, 1992 to February 28, 1993 the Abbott EIA assay was used in 49 and from March 1, 1993 to May 3, 1996 the Abbott IMx assay was used in 171. PAP assays were analyzed individually and the results were combined with pretreatment prostate specific antigen (PSA) values to assess the ability to predict organ confined prostate cancer and serological recurrence after radical prostatectomy. RESULTS: PAP testing was not of value for predicting organ confined disease or positive margins. However, this test was useful for predicting the first serological PSA recurrence in the 3 periods (77 to 85% correct) and overall (82% correct, p < 0.001, odds ratio 6.06). The Kaplan-Meier disease-free survival rate at 4 years was 78.8% for men with PAP less than 3 ng./ml. and 38.8% for those with PAP 3 ng./ml. or greater, which was significant when pretreatment PSA was less than 10 ng./ml. (p = 0.047), 10 ng./ml. or greater (p = 0.012) and overall (p < 0.001). PAP testing added prognostic information to pretreatment PSA values and it was an independent predictor of recurrence. CONCLUSIONS: The widely available and inexpensive PAP assays of the 1990s are predictors of recurrence after radical prostatectomy. They should be included in future studies of prostate cancer recurrence modeling. However, they do not predict pathological stage or margin status. 相似文献