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101.
Alterations in outer membrane proteins of Pseudomonas aeruginosa associated with selective resistance to quinolones. 总被引:17,自引:14,他引:3 下载免费PDF全文
Electrophoresis of outer membrane proteins in three ciprofloxacin-resistant strains of Pseudomonas aeruginosa isolated during therapy and their in vitro revertants indicated that diminution or loss of a 31- to 32-kilodalton outer membrane protein correlated with resistance in two of the three isolates. Resistance was unstable and caused no cross-resistance with other antibiotics. 相似文献
102.
103.
104.
S K Ohri L A Desa H Lee T Patel J Jackson J P Lavender J Spencer 《Journal of the Royal College of Surgeons of Edinburgh》1992,37(5):328-332
A total of 51 technetium-99m (99mTc)-labelled autologous red cell (LRC) scans performed on 49 patients for the localization of obscure gastrointestinal bleeding over a 5-year period was reviewed. The sensitivity for LRC scanning was 72.7% with a positive predictive value of 84.2%. Forty patients underwent both LRC scanning and visceral angiography during the same admission; angiography had a sensitivity of 38.9% compared with 66.7% for LRC scanning and the positive predictive values were 77.8% and 85.7%, respectively. Overall, the site of bleeding was located in 22 (45%) of 49 patients, but LRC scanning alone was successful in identifying the lesion in 16 (33%) cases. In patients who continue to bleed to the point of requiring operation, a combination of scintigraphy and angiography will localize a source in 70% of patients. 相似文献
105.
106.
Sleep hypoxia in myotonic dystrophy and its correlation with awake respiratory function. 总被引:2,自引:1,他引:1 下载免费PDF全文
BACKGROUND--Tiredness and daytime respiratory failure occur frequently in myotonic dystrophy. Sleep hypoxaemia was studied in 12 patients with myotonic dystrophy and correlations were sought with their daytime lung and respiratory muscle function. METHODS--All patients underwent overnight sleep studies, clinical assessment, measurement of flow-volume loops and carbon monoxide transfer factor, arterial blood gas analysis, and physiological assessment of both thoracic muscle function and upper airways obstruction. RESULTS--The mean nadir of oxygen saturation during sleep was 75% (95% confidence interval 69% to 81%). A mean of 3.4% of total sleep duration was spent at an oxygen saturation level below 85%. Five of the 12 patients had an apnoea index of > 5, the group mean apnoea/hypopnoea index being 15.8 events/sleep hour. The mean awake arterial oxygen tension (PaO2) was 10.7 kPa. There was a trend to hypercapnoea with a mean awake arterial carbon dioxide tension of 6.1 kPa; carbon dioxide retention worsened during sleep. Respiratory muscle dysfunction was mainly evident as a low maximum expiratory mouth pressure. Upper airway obstruction assessed by physiological criteria was found in four of the 12 patients. The proportion of total sleep duration with oxygen saturation levels below 85% was directly related to body mass index (weight/height2) and inversely related to the awake PaO2. Body mass index was inversely related to the overnight nadir of oxygen saturation. CONCLUSIONS--Patients with myotonic dystrophy are often hypoxic during sleep and the subgroup that are obese, or have symptoms of sleep apnoea, or both, are particularly at risk. Sleep studies should be considered in this subgroup of patients with myotonic dystrophy. 相似文献
107.
Summary Throughout history, different etiologies have been suggested for torus palatinus. In more recent years, however, torus palatinus has been attributed to heredity; a case which confirms this is presented. The relevant literature is reviewed. 相似文献
108.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
109.
P. A. Crowley-Nowick E. Campbell R. E. Schrohenloher J. Mestecky S. Jackson 《Immunological investigations》1996,25(1):91-101
High pressure liquid chromatography (HPLC) was used to fractionate redissolved polyethylene glycol (PEG) precipitates isolated from the sera of normal volunteers and from patients with IgA nephropathy (IgAN) and systemic lupus erythematosus (SLE), 2 diseases characterized by elevated levels of circulating immune complexes. The individual fractions were analyzed by solid phase ELISA for IgA, IgM, C3, IgG, and complexes of IgG-IgA and IgG-C3. Although PEG precipitates were enriched for high molecular weight IgA and IgG (presumably bound within CIC), significant amounts of IgM, unbound IgG and C3 were also present. The quantities of the PEG-precipitable proteins did not correlate with their serum concentrations. IgG-IgA and IgG-C3 complexes were found in all precipitates examined, but the levels of complexes were higher in both patient groups. These results indicate that PEG precipitates a considerable quantity of proteins not bound in immune complexes. There appeared to be greater protein precipitation from sera of the patient groups compared to the amount precipitated from the normal sera. These results suggest that an understanding of the mechanism of PEG precipitation may be important in defining abnormalities in IgAN, SLE and perhaps other diseases characterized by elevated levels of CIC. In addition, the possibility of undetected CIC in PEG precipitable material must be considered. 相似文献
110.
Use of virologic assays for detection of human immunodeficiency virus in clinical trials: recommendations of the AIDS Clinical Trials Group Virology Committee. 总被引:13,自引:9,他引:4 下载免费PDF全文
S Hammer C Crumpacker R D'Aquila B Jackson J Lathey D Livnat P Reichelderfer 《Journal of clinical microbiology》1993,31(10):2557-2564