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1.
Identification of a Klebsiella pneumoniae strain associated with nosocomial urinary tract infection. 下载免费PDF全文
K S Kil R O Darouiche R A Hull M D Mansouri D M Musher 《Journal of clinical microbiology》1997,35(9):2370-2374
To differentiate between relapse of infection and reinfection of the urinary tract due to Klebsiella pneumoniae, 33 K. pneumoniae isolates collected from 20 patients with spinal cord injury (SCI) over 2 years were typed by genomic fingerprinting by repetitive-element PCR. Clinical isolates obtained from the same patients with recurrent episodes of urinary tract infection (UTI) revealed identical genomic fingerprints indicating relapse of UTI due to K. pneumoniae, despite appropriate antibiotic therapy. Seventeen isolates obtained from 8 of the 20 SCI patients shared a common genotype, termed RD6. Among non-SCI patients residing in other nursing units, the RD6 genotype was found in 5 of 10 patients with K. pneumoniae UTI but in only 1 of 20 patients with K. pneumoniae infection that did not involve the urinary tract, suggesting a strong association of this genotype with UTI. All RD6 isolates exhibited strong adherence (> or =50 adherent bacteria per cell) to HEp-2 cells, whereas other K. pneumoniae isolates generally did not adhere to or adhered very weakly to HEp-2 cells (< or =5 adherent bacteria per cell). Adherence was inhibited either by 4% D-mannose or by anti-type 1 fimbrial rabbit serum. These results suggest that the capacity of K. pneumoniae RD6 isolates to cause UTI may be mediated by its striking adherence to mammalian cells. 相似文献
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M. S. Levine A. M. Adinolfi R. S. Fisher C. D. Hull D. Guthrie N. A. Buchwald 《Brain research》1988,440(2):267-279
These studies provide information on the changes in the ultrastructure in the caudate nucleus of aged cats. The major findings was that there was a decrease in the density of synapses in caudate neuropil. This decrease occurred in animals after 3 years of age and remained relatively constant in older animals. In conjunction with this change a population of unusually long synapses also occurred. These larger synaptic appositions were associated with enlarged spine heads. The caudate also showed a number of qualitative ultrastructural alterations. Many neurons contained accumulations of lipofuscin or lipopigment granules in aged animals. These inclusions occurred in both soma and dendrites of neurons and all types of glial cells. A unique configuration of collapsed agranular cisterns also was observed in aged animals. The present results indicate that decreases in synaptic density may by one morphological event underlying functional alterations observed in caudate neurons in aged cats. 相似文献
5.
Does changing from mercury to electronic blood pressure measurement influence recorded blood pressure? An observational study. 下载免费PDF全文
Richard J McManus Jonathan Mant Martyn R P Hull F D Richard Hobbs 《The British journal of general practice》2003,53(497):953-956
Mercury sphygmomanometers have been commonly used in primary care to measure blood pressure but are associated with bias. Electronic blood pressure machines are being introduced in many practices and have anecdotally been associated with higher recorded blood pressure. This study examined recorded blood pressure in four practices before and after electronic blood pressure machine introduction. No consistent change in mean blood pressure was apparent following their introduction, but there was a large and significant fall in terminal digit preference suggesting improved precision of recording. 相似文献
6.
Sequential contrast-enhanced MR imaging of the penis 总被引:1,自引:0,他引:1
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We have developed a computerized neuromuscular monitoring system (NMMS) using commercially available subsystems, i.e., computer
equipment, clinical nerve stimulator, force transducer, and strip-chart recorder. This NMMS was developed for acquisition
and analysis of data for research and teaching purposes. Computer analysis of the muscle response to stimulation allows graphic
and numeric presentation of the twitch response and calculated ratios. Since the system can store and recall data, research
data can be accessed for analysis and graphic presentation. An IBM PC/AT computer is used as the central controller and data
processor. The computer controls timing of the nerve stimulator output, initiates data acquisition, and adjusts the paper
speed of the strip chart recorder. The data processing functions include establishing control response values (when no neuromuscular
blockade is present), displaying force versus time and calculated data graphically and numerically, and storing these data
for further analysis. The general purpose nature of the computer and strip chart recording equipment allow modification of
the system primarily by changes in software. For example, new patterns of nerve stimulation, such as the posttetanic count,
can be programmed into the computer system along with appropriate data display and analysis routines. The NMMS has functioned
well in the operating room environment. We have had no episodes of electrocautery interference with the computer functions.
The automated features have enhanced the utility of the NMMS. The prime advantages of this system are (1) the ability to customize
its features by altering its controlling programs, (2) the ready availability of the hardware and software, (3) the general
purpose nature of the system, so that it is not limited to this one application, and (4) the adaptable nature of the system. 相似文献
8.
The pattern electroretinogram (PERG) has recently been introduced as a clinical procedure. It has been thought by many to represent activity of the retinal ganglion cells, although this is still a matter of contention. The exciting prospect of a selective test of ganglion cell function led to the application of the PERG in a variety of ophthalmological conditions. In the course of these investigations the PERG was found to be diminished in cases of maculopathy, optic atrophy, optic neuritis, toxic optic neuropathy, neurotransmitter disorders, glaucoma and ocular hypertension and in retinal vascular disorders such as diabetes. It was also affected in some cases of amblyopia. This paper briefly describes the techniques used to record the PERG and reviews current literature pertaining to its clinical application. 相似文献
9.
Chlamydial etiology of acute lower respiratory tract infections in children in the Sudan 总被引:2,自引:0,他引:2
B Herrmann MAM Salih BE Yousif O Abdelwahab P-A Mårdh 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(2):169-172
The role of Chlamydia pneumoniae in 110 Sudanese children with signs of acute lower respiratory tract infections (ALRI) was investigated. Four (3.6%) had evidence of C. pneumoniae infection, of whom 3 were culture-positive, while 1 had an antibody response suggesting a recent infection. IgG antibodies at a titer of ≥1:32 to C. pneumoniae, Chlamydia psittaci and Chlamydia trachomatis were detected in 27 (24.5%), 27 (24.5%) and 7 (6.4%) of the 110 ALRI cases, respectively. C. pneumoniae, C. trachomatis or C. psittaci were not detected in nasopharyngeal secretions from any of 110 patients when fluorescence-labeled specific monoclonal antibodies were used. In a seroepidemiological survey, 318 healthy Sudanese persons aged between 1 month and 67 years were studied for C. pneumoniae antibodies. 相似文献
10.
M L Hull M Williams K Williams S Kautz 《Medicine and science in sports and exercise》1992,24(10):1114-1122
The purpose of this study was to compare physiological variables of endurance-trained cyclists riding with four different chainring designs: round, Shimano Biopace, and two engineered ellipse designs. The ellipse designated Eng10 had the crank arm oriented 10 degrees forward of the major (i.e. longer) axis. Eighty degrees further forward, along the minor axis, was the crank arm orientation for the second ellipse, Eng90. With the major to minor axis ratio of 22.9 cm/16.8 cm (1.36), both ellipses imposed a crank angular velocity variation of 27% relative to the highest velocity assuming constant chain velocity. Best described as a skewed ellipse (i.e., major and minor axes not perpendicular), the Biopace had a major to minor axis ratio of 1.09 thus giving a crank angular velocity variation of 8%. Eleven male cyclists rode at a high (80% of maximum VO2) and a low (60% of maximum VO2) workrate using each chainring. The study was conducted over four consecutive days with the presentation order of the chainrings randomized. Open circuit spirometry was used to collect continuous respiratory data. Heart rate, blood lactate, and cadence values also were measured. None of the physiological variables including rates of oxygen consumption showed significant differences among the chainrings. Thus, the gross efficiency of cycling was not improved by any of the noncircular chainrings. For cycling events where efficiency is a determinant of performance, the noncircular chainrings do not offer any advantage over round chainrings. 相似文献