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Because a retrospective study detected 13 negative Western blots out of 38 single-use diagnostic system (SUDS)-positive cases over a 1-year period, we performed a prospective study to compare the performance of the SUDS test with that of enzyme immunoassay (EIA). Of 888 SUDS-tested sera, 875 (98.4%) were both SUDS and EIA negative and 5 (0.6%) were SUDS, EIA, and Western blot positive. The rate of SUDS-positive samples decreased from 3.16/month in the retrospective study to 1.33/month in the prospective study. The immunoassays had sensitivities and specificities of 100 and 99.7 (SUDS) and 100 and 99.4% (traditional EIA), respectively. In laboratories with experienced personnel, the SUDS test performs as well as the EIA as a screen for infection with the human immunodeficiency virus.  相似文献   
3.
Seven lean healthy young men were studied for 6 weeks during exposure to pharmacologic inhibition or stimulation of the sympathetic nervous system. For a period of 2 weeks their beta-adrenergic receptors were either blocked with propranolol hydrochloride (160 mg/d) or stimulated with terbutaline sulphate (15 mg/d). After a further 2 weeks of placebo administration (500 mg lactose/d), the subjects crossed over to the drug they had not been taking at the beginning of the experiment for another 14 days. During the last five days of each 2-week period, the subjects consumed a weight-maintaining diet, composed of 12% protein, 48% carbohydrate, and 40% fat. They consumed exactly the same menus on the same days during the subsequent study periods. Body weight and physical activity were measured every day for 6 weeks. Daily heart rate and nitrogen excretion were measured continuously for days at the end of each 2-week period, the last two days of which were spent in a respiration chamber where energy expenditure and a variety of metabolic parameters were measured. In the respiration chamber on the propranolol, placebo, and terbutaline treatments, respectively, significant differences were observed in mean daily heart rate (65 +/- 3, 75 +/- 4, and 84 +/- 4 beats/min), mean sleeping heart rate (51 +/- 2, 56 +/- 3, and 62 +/- 3 beats/min), nitrogen excretion (13.6 +/- 0.7, 12.6 +/- 0.6, and 11.9 +/- 0.6 g/d), fat oxidation (+1,045 +/- 95, +1,243 +/- 148, and +1,278 +/- 84 kcal/d) and thyroid hormones (12.0 +/- 0.7, 15.7 +/- 0.9, and 17.2 +/- 1.0 T3/T4 ratio).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
The development of locomotor function in the rat spans the first 3 postnatal weeks. We have studied morphological features of the soma and dendrites of motoneurons innervating the physiological flexor muscles of the ankle, tibialis anterior and extensor digitorum longus, by intracellular injection in vitro between the first and ninth postnatal days. We obtained serial optical sections of 96 adequately filled motoneurons in whole-mounted hemisected spinal cords by confocal microscopy, projected them onto a single plane and analysed them morphometrically. On the day after birth, the somatodendritic surfaces of most such motoneurons were covered in growth-associated spiny, thorny or hair-like appendages. These had disappeared from the soma by the fourth postnatal day and from most proximal dendrites by day 7, but were still common distally on day 9. During this period there was little or no net growth of either the soma (which was still much smaller than in the adult) or the dendritic tree. A dorsal dendritic bias was present and 'sprays' of long, loosely bundled dorsal dendrites were often seen. The mean number of primary dendrites remained constant at about eight, and their combined diameter was already significantly correlated with mean soma diameter, as in the adult cat. Thus, the critical neonatal period during which these ankle flexor motoneurons are known to change their electrophysiological properties and to be particularly sensitive to interference with neuromuscular interaction is characterized by major changes in the neuronal surface, presumably linked to synaptogenesis.  相似文献   
5.
Catalase plays a key role as an antioxidant, protecting aerobic organisms from the toxic effects of hydrogen peroxide, and in some cases has been postulated to be a virulence factor. To help elucidate the function of catalase in Candida albicans, a single C. albicans-derived catalase gene, designated CAT1, was isolated and cloned. Degenerate PCR primers based on highly conserved areas of other fungal catalase genes were used to amplify a 411-bp product from genomic DNA of C. albicans ATCC 10261. By using this product as a probe, catalase clones were isolated from genomic libraries of C. albicans. Nucleotide sequence analysis revealed an open reading frame encoding a protein of 487 amino acid residues. Construction of a CAT1-deficient mutant was achieved by using the Ura-blaster technique for sequential disruption of multiple alleles by integrative transformation using URA3 as a selectable marker. Resulting mutants exhibited normal morphology and comparable growth rates of both yeast and mycelial forms. Enzymatic analysis revealed an abundance of catalase in the wild-type strain but decreasing catalase activity in heterozygous mutants and no detectable catalase in a homozygous null mutant. In vitro assays showed the mutant strains to be more sensitive to damage by both neutrophils and concentrations of exogenous peroxide that were sublethal for the parental strain. Compared to the parental strain, the homozygous null mutant strain was far less virulent for mice in an intravenous infection model of disseminated candidiasis. Definitive linkage of CAT1 with virulence would require restoration of activity by reintroduction of the gene into mutants. However, initial results in mice, taken together with the enhanced susceptibility of catalase-deficient hyphae to damage by human neutrophils, suggest that catalase may enhance the pathogenicity of C. albicans.  相似文献   
6.
Chemokines are a superfamily of small chemotactic proteins. While increased levels of interleukin-8 have been measured in serum and urine during urinary tract infection, little is known about other chemokines in this condition. Monocyte chemoattractant protein (MCP)–1, macrophage inflammatory protein (MIP)–1, MIP-1 and interferon- inducible protein (IP)–10 were measured in 30 patients with culture-proven urosepsis during a 3-day follow-up and in 11 healthy humans after intravenous injection of endotoxin (4 ng/kg). Urine and serum levels of MCP-1, MIP-1, and IP-10, but not of MIP-1, were elevated in patients on admission, and decreased after initiation of antibiotic treatment. Endotoxin administration to healthy subjects induced increases in plasma and urine concentrations of all four chemokines. These data indicate that clinical and experimental gram-negative infection in humans is associated with enhanced production of chemokines that act mainly on mononuclear cells and that these chemokines are at least in part locally produced.  相似文献   
7.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Wissenschaftliche Ergebnisse können eine Wissensquelle für kommunale Akteurinnen und Akteure der...  相似文献   
8.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Kommunale AkteurInnen erfahren bei der Entwicklung und Auswahl von Maßnahmen der Prävention und...  相似文献   
9.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Seit Mai 2020 können Hersteller einen Antrag zur Aufnahme einer digitalen Gesundheitsanwendung (DiGA) in das Verzeichnis...  相似文献   
10.
The Terumo Capiox SX18R is a commercially available, low prime, reverse phase, hollow fiber membrane oxygenator. The oxygenator consists of a 1.8 m2 microporous polypropylene hollow fiber bundle, a 2200 cm2 tubular stainless steel heat exchanger, and an open hard shell venous reservoir with integral cardiotomy filter. The Terumo Capiox SX18R oxygenator was evaluated to determine its clinical oxygenating performance. Blood samples were drawn from 25 patients yielding 114 data points. The following parameters were recorded: blood flow, cardiac index, gas flow, gas to blood flow ratio, and oxygen fraction. Samples were assayed for hematocrit, hemoglobin, arterial and venous blood gas values, and venous oxygen saturation. The data and assay results were used to calculate arterial, venous, and membrane gas oxygen content, oxygen transfer, shunt fraction, and oxygen diffusion capacity. The Terumo Capiox SX18R oxygenator performed adequately with sufficient oxygen transfer reserve and carbon dioxide clearance under a variety of clinical conditions for the tested population.  相似文献   
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