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71.
72.
Summary A patient with chronic relapsing inflammatory demyelinating polyneuropathy was successfully treated with plasma exchanges and cyclosporin A (CsA). Dynamometric measurements of hand force during the time of CsA treatment showed a highly significant correlation between hand force and CsA blood levels. The largest influence of CsA on hand force occurred 11–13 days after CsA uptake. 相似文献
73.
E W Hafner B W Holley K S Holdom S E Lee R G Wax D Beck H A McArthur W C Wernau 《The Journal of antibiotics》1991,44(3):349-356
The eight natural avermectins produced by Streptomyces avermitilis have the carbon skeleton of either isobutyric or S-2-methylbutyric acid incorporated into their structures. A mutant of S. avermitilis has been isolated that contains no functional branched-chain 2-oxo acid dehydrogenase activity. The mutant, in contrast to its parent, is unable to grow with isoleucine, valine and leucine as carbon sources. In medium lacking both S(+)-2-methylbutyric and isobutyric acid, the mutant is also incapable of making the natural avermectins, while supplementation with either one of these compounds restores production of the corresponding four natural avermectins. These facts indicate that in S. avermitilis the branched-chain 2-oxo acid dehydrogenase enzyme functions not only to catabolize the cellular branched-chain amino acids in order to meet energy and growth requirements but also to provide the small branched-chain organic acid precursor molecules necessary for avermectin biosynthesis. Supplementation of the mutant strain with R(-)-2-methylbutyric acid yields novel isomeric avermectins unseen in the (unsupplemented) wild-type strain. It was also concluded that acetate and propionate production by branched-chain 2-oxo acid degradation is not absolutely essential for avermectin production. 相似文献
74.
Functional alterations in noxious, sensory and motor circuits within the central nervous system may play an important role in the pathophysiology of complex regional pain syndrome (CRPS). The aim of the present study was to search for further evidence of hyperexcitability in the hemisphere contralateral to the affected limb in patients with CRPS by employing both psychophysical and transcranial magnetic stimulation (TMS) methods. Twelve patients with CRPS type I, confined to the distal part of a limb (six in an upper-limb and six in a lower-limb), were enrolled in the study. The quantitative thermal, mechanical and 'wind-up' like pain testing was performed at the most painful site in the affected limb and in the ipsilateral limb. Results were then compared to those found at mirror sites in the contralateral limbs. TMS was used to assess the inter-hemispheric difference in parameters of corticospinal excitability, intracortical inhibition, and intracortical facilitation. The quantitative thermal and mechanical testing showed significant differences in cold, heat and mechanical pain thresholds, as well as in the first and last 'wind-up' stimuli between the affected and the contralateral limbs of the CRPS patients. No significant differences between the ipsilateral unaffected limbs and their contralateral pair limbs were found. A significant reduction in the short intracortical inhibition associated with a significant increase of the I-wave facilitation was found in the hemisphere contralateral to the affected side in the upper-limb CRPS group. No significant inter-hemispheric asymmetry between the affected and the non-affected sides was revealed in the lower-limb CRPS group. Taken together, these results suggest that in patients with well-localized CRPS, there is evidence for sensory and motor CNS hyperexcitability, though it seems to involve only corresponding regions within the CNS rather than the entire hemisphere. 相似文献
75.
M Müller-Bardorff C Sylvén G Rasmanis B J?rgensen P O Collinson U Waldenhofer M M Hirschl A N Laggner W Gerhardt G Hafner I Labaere R Leinberger R Zerback H A Katus 《Clinical chemistry and laboratory medicine》2000,38(6):567-574
We present the results of a multicenter evaluation of a new point-of-care system (Cardiac Reader) for the quantitative determination of cardiac troponin T (CARDIAC T Quantitative test) and myoglobin (CARDIAC M test) in whole blood samples. The Cardiac Reader is a CCD camera that optically reads the immunochemical test strips. The measuring range is 0.1 to 3 microg/l for CARDIAC T Quantitative and 30 to 700 microg/l for CARDIAC M. Both tests are calibrated by the manufacturer. The reaction times of the tests are 12 or 8 minutes, respectively. Method comparisons were performed with 281 heparinized blood samples from patients with suspected acute coronary syndromes. The results obtained with CARDIAC T Quantitative showed a good agreement compared with cardiac troponin T ELISA (r = 0.89; y = 0.93x + 0.02). The method comparison between CARDIAC M and Tina-quant Myoglobin also showed a good agreement between both assays (r = 0.98; y = 0.92x + 1.6). Test lot-to-lot comparisons yielded differences of 2% and 6% for CARDIAC T Quantitative and of 0 to 11% for CARDIAC M. The within-run imprecision with blood samples and control materials was acceptable for CARDIAC T Quantitative (CV 10 to 15%) and good for CARDIAC M (CV 5 to 10%). The between-instrument CV was below 7% for CARDIACT Quantitative and below 5% for CARDIAC M. The cross-reactivity of CARDIAC T Quantitative with skeletal troponin T was approximately 0.003%. No significant analytical interference was detected for any of the assays in investigations with biotin (up to 100 microg/l), hemoglobin (up to 0.125 mmol/l), hematocrit (26 to 52%), bilirubin (up to 340 micromol/l), triglycerides (up to 5.0 mmol/l), and 18 standard drugs. With the Cardiac Reader reliable quantitative results can be easily obtained for both cardiac markers. The system is, therefore, particularly suitable for use in emergency rooms, coronary care units and small hospitals. 相似文献
76.
Development of resistance to ciprofloxacin, rifampin, and mupirocin in methicillin-susceptible and -resistant Staphylococcus aureus isolates
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Schmitz FJ Fluit AC Hafner D Beeck A Perdikouli M Boos M Scheuring S Verhoef J Köhrer K Von Eiff C 《Antimicrobial agents and chemotherapy》2000,44(11):3229-3231
A relationship between resistance to methicillin and resistance to fluoroquinolones, rifampin, and mupirocin has been described for Staphylococcus aureus. Differences in resistance rates may be explainable by a higher spontaneous mutation rate (MR) or a faster development of resistance (DIFF) in methicillin-resistant S. aureus (MRSA). No differences in MR, DIFF, and mutations in grlA and gyrA were detected between methicillin-susceptible S. aureus and MRSA. The higher resistance rates in MRSA are not the result of hypermutability of target genes or a faster emergence of different mutations and may be the consequence of clonal spread of multiresistant MRSA. 相似文献
77.
Susanne Kolbe-Busch Johannes Lotz Gerd Hafner Norbert J C Blanckaert Georg Claeys Giovanni Togni Jürgen Carlsen Ralf R?ddiger Lothar Thomas 《Clinical chemistry and laboratory medicine》2002,40(5):529-536
Soluble transferrin receptor (sTfR) is reported to be a reliable marker for the diagnosis of iron deficiency, especially when iron metabolism is influenced by inflammatory disorders such as infection, chronic inflammation and cancer-related anemia. In the present multicenter study the analytical performance of a recently introduced, latex-enhanced immunoturbidimetric assay for the determination of soluble transferrin receptor (Tina quant [a] sTfR, Roche Diagnostics) on different fully mechanized analyzers such as Hitachi 917 and 911, and Cobas Integra 400 and 700 was evaluated. Within-run and between-run imprecision showed good results (CV<5% and <7%, respectively). The assay was found to be linear over a wide measuring range (0.4-35 mg/l). Endogenous substances did not interfere with the test results. Comparison of serum sTfR concentrations with those of heparinized plasma revealed good correlation (r>0.976). Method comparison with an existing fully mechanized method as well as with ELISA tests for sTfR showed very good correlation (r>0.987). Because of the lack of international standardization the results differed from each other up to 2.5-fold. The 95% of serum levels in healthy individuals ranged from 1.9 to 4.4 mg/l (n=427). However, the reference ranges should be reported in a sex-dependent manner, as 2.2-5.0 mg/l for men (n=211) and as 1.9-4.4 mg/l for premenopausal (n=216) and postmenopausal (n=45) women. The Tina quant [a] sTfR assay enables the precise, accurate, rapid and convenient determination of sTfR concentrations for routine clinical chemistry purposes. 相似文献
78.
A nationwide study on the impact of shared values on staff nurse job satisfaction and perceived productivity was done in 24 hospitals under different auspices, some of which were also Magnet Hospitals. Data were obtained from a 25% random sample of the staff nurse population (N = 2,336), 58% of the head nurse group, 65% of the clinical experts, and 66% of the top management. Staff nurses and clinical experts had more value congruence than did staff nurses and head nurses. A significant inverse correlation was found between value congruence and nurse job satisfaction and quality care. Explanations of the finding center on recent role changes for both staff nurses and head nurses, power differential, and evolving clarity of the staff nurse role. A serendipitious finding was that staff nurses reported fewer factors as important to their job satisfaction and perceived environment conducive to quality patient care than did other members of the nursing department. However, factors important to staff nurses were very important. 相似文献
79.
80.
In this study, the potential of lecithin/chitosan nanoparticles (NPs) as colloidal nanosystem for transdermal melatonin delivery was investigated. Mean diameter and zeta-potential of NPs differing in lecithin type (Lipoid S45 and S100) and chitosan content ranged between 113.7 and 331.5?nm and 4.6 and 31.2?mV, respectively. Melatonin loadings were up to 7.2%. The potential of lecithin/chitosan NPs to enhance transdermal melatonin delivery was investigated by determining the drug flux across dermatomed porcine skin and its skin deposition. Lecithin/chitosan NPs provided 1.3-2.3-fold higher flux compared to melatonin solution. The highest flux, 9.0?±?0.21?μg/cm2/h, was observed for S45 lecithin/chitosan NPs with lecithin/chitosan weight ratio of 20:1. NP possible cytotoxicity in vitro was evaluated using human skin keratinocytes and fibroblasts. It was demonstrated that lecithin/chitosan NPs can be applied to skin cells at concentrations up to 200?μg/mL without inducing plasma membrane damage or cell viability decrease. 相似文献