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61.
Urinary tract infections (UTIs) are common conditions in clinical practice. For uncomplicated UTIs, the causative organisms and their antimicrobial susceptibility profiles are generally predictable, and empiric short course (3 day) antibiotic therapy after an abbreviated laboratory workup is advocated. Acute pyelonephritis requires a 2 week antibiotic course, often with initial parenteral therapy. Women with frequent recurrences of UTIs may require intermittent self-treatment or continuous or postcoital antibiotic prophylaxis. Catheter-associated UTIs generally only require treatment if the patient shows signs of systemic infection. Treatment of asymptomatic bacteriuria is only recommended in certain circumstances. Careful consideration of the clinical circumstances, the patient's known or predicted urinary tract anatomy, and the antibiotic susceptibility of the bacterial pathogen(s) are critical factors in the choice of appropriate therapy for urinary tract infections. 相似文献
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P Lahermo A Sajantila P Sistonen M Lukka P Aula L Peltonen ML Savontaus 《Canadian Metallurgical Quarterly》1996,58(6):1309-1322
The genetic relationships between two Finno-Ugric-speaking populations, the Finns and the Finnish Saami (Lapps), were studied by using PCR for six nuclear-DNA marker loci, mitochondrial restriction-site polymorphism, and sequence variation of a 360-bp segment of the mitochondrial control region. The allele frequencies of each of the nuclear-DNA marker loci and the frequencies of mtDNA restriction haplotypes were significantly different between the populations. The Saami showed exceptionally low variation in their mtDNA restriction sites. The 9-bp deletion common in East Asian populations was not observed, nor did the haplotype data fit into the haplogroup categorization of Torroni et al. The average number of nucleotide substitutions from the mtDNA haplotype data indicated that the Finnish Saami may be closer to the Finns than to the other reference populations, whereas nuclear DNA suggested that the Finns are more closely related to the European reference populations than to the Finnish Saami. The similarity of the Finns to the other Europeans was even more pronounced according to the sequence data. We were unable to distinguish between the Finns and either the Swiss or Sardinian reference populations, whereas the Finnish Saami clearly stood apart. The Finnish Saami are distinct from other Circumarctic populations, although two of the lineages found among the Saami showed closer relationship to the Circumarctic than to the European lineages. The sequence data indicated an exceptionally high divergence for the Saami mtDNA control lineages. The distribution of the pairwise nucleotide differences in the Saami suggested that this population has not experienced an expansion similar to what was indicated for the Finns and the reference populations. 相似文献
64.
R Mann EK Yeong ML Moore LH Engrav 《Canadian Metallurgical Quarterly》1997,18(2):160-3; discussion 159
This article introduces a new tool to measure the pressure that is under pressure garments. The Iscan (Tekscan, Inc.) system uses a patented ultra-thin (0.007 inch) sensor with multiple sensing locations that sample continuously at 100 times per second. It is noninvasive, convenient, and quick. The study had two parts. First, we established the validity and reliability of the device. Next, garment/scar interface pressures were measured on new garments with use of the Iscan system. Four garment types were studied, with 10 measurements made in each group: Isotoner gloves (Smith & Nephew Roylan, Inc.); custom-fit pressure gloves; Tubigrip forearm sleeves (Seton Health Care Group); and custom-fit pressure forearm sleeves. Mean garment/scar interface pressures were 18 +/- 2 mm Hg for the Isotoner glove, 34 +/- 5 mm Hg for the custom-fit pressure glove, 20 +/- 7 mm Hg for the Tubigrip sleeve, and 35 +/- 6 mm Hg for the custom-fit sleeve. We concluded that the Iscan system can be used to measure pressure under pressure garments accurately and reliably, and that custom-fit hand and forearm garments provide more pressure than Isotoner gloves or Tubigrip sleeves. 相似文献
65.
Rothenberg B.C. Brown J.E.C. Hurst P.J. Lewis S.H. 《Solid-State Circuits, IEEE Journal of》1997,32(5):713-721
A mixed-signal RAM decision-feedback equalizer (DFE) that operates at 90 Mb/s is described. In the analog domain, the DFE subtracts intersymbol interference caused by the past four outputs. The equalized signal is fed into a nonuniform flash analog-to-digital converter (ADC) to produce the decision output and error signal used to adapt the RAM contents in the digital domain. With a 5 V supply voltage, the power dissipation is 260 mW during steady-state operation. The active area is 4.5 mm2 in a 1 μm CMOS process 相似文献
66.
Necrotizing fasciitis (NF) is a rapidly progressive soft tissue infection with high morbidity and mortality rates. Its occurrence in the head and neck region is uncommon, the majority of reported cases being limited to involvement of the neck, usually from infections of dental or pharyngeal origin. Involvement of the face from NF is rare; only 35 such cases have been reported in the literature since 1960. It is not only associated with a high mortality but can also result in severe disfigurement of the face, posing challenging reconstructive problems. Successful management of facial NF requires early diagnosis, prompt institution of broad spectrum antibiotics, aggressive surgical debridement to control the infection, and reconstruction of the resultant soft tissue defects. This report describes four additional cases of facial necrotizing fasciitis. One of the four patients died as a result of sepsis and multi-organ system failure. Two of the three surviving patients had significant facial disfigurement. A comprehensive review of the facial NF cases reported in the literature is also provided. Based on our experience with facial NF and the results of all previous case reports, the clinical manifestations, pathogenesis, and management of this disease are discussed. 相似文献
67.
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69.
Beamed microwave power transmission and its application to space 总被引:5,自引:0,他引:5
The general principles and special components of beamed microwave power transmission systems are outlined, and their application to the space program is discussed. For a beamed system starting with a DC source of power, converting it to a microwave beam for transmission through space, and ending with DC power output at the receiving end, an experimentally measured and certified DC-to-DC efficiency of 54% has been achieved. The application that is discussed in detail is a low-earth-orbit-to-geostationary-orbit (LEO to GEO) transportation system that depends on vehicles propelled by electric thrusters whose power is supplied by a microwave beam originating at the earth's surface. A scenario for such a system is chosen, and the performance results are presented. The advantages of the all electronic system over a chemically propelled system are enumerated. The principles of space propulsion, particularly as they relate to electric propulsion, are outlined. Key components at the terminals of the system are discussed. Environmental considerations are discussed 相似文献
70.