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51.
Evaluation of an extended blood culture protocol to isolate fastidious organisms from patients with AIDS. 下载免费PDF全文
M J Dougherty D H Spach A M Larson T M Hooton M B Coyle 《Journal of clinical microbiology》1996,34(10):2444-2447
Recent reports of fastidious pathogens suggest the need for special blood cultures for immunocompromised patients. Blood cultures from 45 human immunodeficiency virus (HIV)-infected patients with unexplained fever (> or = 38.0 degrees C) and CD4 counts of < 125 cells per mm3 were collected into a vacuum tube with sodium polyanetholsulfonate, an Isolator tube, and BACTEC aerobic and anaerobic bottles. Blood from the sodium polyanethosulfonate tube was inoculated into BACTEC 13A bottles, which were read weekly for 16 weeks. Isolator sediment was divided among eight agar media, including four sheep blood agar media: chocolate agar, brain heart infusion blood agar, heart infusion blood agar, and brucella blood agar. Other agar plates included Sabouraud's, buffered charcoal-yeast extract, Middlebrook 7H11 (M7H11) with hemoglobin, and M7H11 with mycobactin J. Incubation conditions included air and CO2-enriched aerobic, microaerophilic, and anaerobic atmospheres. Aerobic BACTEC broths received an acridine orange stain on day 8 and were subcultured at 2, 4, and 8 weeks. Anaerobic BACTEC bottles were subcultured at 4 weeks. All solid media, including subcultures, were incubated for 8 weeks, providing a total of 16 weeks of incubation for each specimen. Clinically significant isolates included eight Mycobacterium avium complex isolates and one each of Bartonella henselae, Bartonella quintana, Shigella flexneri, Klebsiella oxytoca, and Cryptococcus neoformans. All isolates were detected with commercially available media and, with the exception of Bartonella spp., were recovered within incubation times routinely used in most clinical laboratories. 相似文献
52.
BACKGROUND: Eosinophils contribute to the pathogenesis of asthma and localize to the lung after allergen exposure by uncertain mechanisms. METHODS: We used intrabronchial instillation of allergen to model the interaction between inhaled allergen and the lung. We measured the number of peripheral blood leukocytes and the expression of VLA-4 (CD49d), Mac-1 (CD11b) and PSGL-1 (CD162) up to 4 h after instillation of allergen into a bronchus of eight atopic asthmatics. For controls, we instilled normal saline into a subset of the asthmatic subjects, and allergen into nonatopic, nonasthmatic subjects. RESULTS: There were changes of total leukocyte number, number of polymorphonuclear leukocytes, lymphocytes, monocytes and eosinophils in all three groups (atopic asthmatics instilled with allergen, atopic asthmatics instilled with saline, nonatopic nonasthmatic subjects instilled with allergen), which were likely related to bronchoscopy. However, the decrease of eosinophils was significant only in the atopic asthmatics instilled with allergen. The remaining eosinophils in the allergen challenged asthmatics were not activated as defined by cell density or change of expression of VLA-4, Mac-1 and PSGL-1. CONCLUSIONS: While eosinophils rapidly and specifically leave the circulation after allergen challenge of atopic asthmatics, the remaining circulating eosinophils are not activated. 相似文献
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1. Psychophysical experiments were initiated to determine the possible influence of increasing stimulus size on perceived pain intensity. Six trained human subjects (5 male, 1 female) made visual analogue scale (VAS) ratings for pain-sensation intensity and unpleasantness in response to nociceptive thermal stimuli. Test stimuli consisted of 5-s duration heat pulses (45-50 degrees C in 1 degrees increments) delivered by one, two, or three contact thermal probes (1 cm2 each) applied to the medial aspect of the anterior forearm. 2. The area of skin receiving noxious thermal stimuli was changed by randomly varying the number of thermodes activated. The effects of varying the distance between the thermal probes also were evaluated. In the first series of experiments, thermal-probe separation was kept close to 0; in subsequent experimental series, the thermodes were separated by either 5 or 10 cm. 3. In each experimental series, considerable spatial summation occurred in both pain-sensation intensity and unpleasantness dimensions of pain. This summation occurred throughout the nociceptive thermal range of 45-50 degrees C and was larger at suprathreshold temperatures (greater than or equal to 47 degrees C) than those near threshold (less than or equal to 46 degrees C). Unlike spatial summation of perceived warmth, that of pain was not characterized by systematic changes in power-function exponents but as approximately upward parallel displacements in double-logarithmic coordinates. 4. Thermal-probe separation over a range of 0-10 cm had no effects on spatial summation of pain-sensation intensity or pain unpleasantness. In contrast, increasing thermal-probe separation increased the subjects' ability to discriminate differences in stimulus size and their ability to detect correctly the number of thermal probes activated. 5. Because affective VAS ratings of unpleasantness were linearly related to, but distinctly and systematically less than, VAS ratings of pain-sensation intensity, it was clear that subjects responded quite differently to these two pain dimensions. Affective judgements were not additionally influenced by thermal probe separation and hence by the ability to perceive stimulus size or number of thermal probes activated. 6. The results indicate that powerful spatial-summation mechanisms exist for heat-induced pain. Spatial summation of pain is likely to be subserved both by local integration mechanisms at the level of single spinothalamic-tract neurons and by recruitment of central nociceptive neurons, because spatial summation of pain occurred to approximately equal extents under conditions of thermode separations over a distance of at least 20 cm. 相似文献
54.
Retrovirus packaging cell lines that express the Moloney murine leukemia virus gag, pol, and env genes and a retroviral vector genome can produce virus particles that are capable of transducing cells. Normally if the packaging cell line does not produce a functional viral fusion glycoprotein, such as the retroviral envelope protein or a foreign viral glycoprotein, then the viruses will be incapable of transducing cells. We have found that incubating envelope protein-deficient virus particles bound to cells with chlorpromazine leads to transduction. Chlorpromazine (CPZ) is a membrane-active reagent that is commonly used to induce the hemifusion to fusion transition when membrane fusion is mediated by partially defective viral glycoproteins. The concentration and pH dependence of the promotion of transduction by CPZ is consistent with a role for CPZ micelle formation in viral entry. These data indicate that caution is warranted when experiments concerning membrane fusion completion promoted by CPZ are analyzed. 相似文献
55.
Diagnostic tests in the evaluation of dementia. A prospective study of 200 elderly outpatients 总被引:1,自引:0,他引:1
E B Larson B V Reifler S M Sumi C G Canfield N M Chinn 《Archives of internal medicine》1986,146(10):1917-1922
We studied the components of the diagnostic evaluation in 200 patients older than 60 years of age with suspected dementia who received standardized diagnostic evaluation and follow-up. The most common dementia diagnoses were Alzheimer's-type dementia (74.5%) and dementia due to toxic effects of drugs (9.5%). Eleven patients with hypothyroidism, metabolic encephalopathies due to hyponatremia, hyperparathyroidism, and hypoglycemia required laboratory tests for diagnosis, whereas the other dementia diagnoses were made primarily on the basis of data available on the history and physical and neurologic examinations. The complete blood cell count, blood chemistry battery (especially sodium, calcium, and glucose concentrations), and thyroid function tests were of definite value for the diagnosis of unsuspected disease and were useful as routine tests in evaluating patients for dementia. A careful history and physical examination accompanied by complete blood cell count, chemistry battery, and a thyroid function test would have been effective in diagnosing treatable illnesses causing cognitive impairment. Other diagnostic tests could have been used selectively based on results of the examination and screening tests. Estimated diagnostic charges from a selective approach would be 25% to 34% of those for the "routine" evaluation. 相似文献
56.
The time required of nurses to cut needles and syringes, the costs of boxes used to cut needles and store used syringes, as well as some of the costs related to treating needlesticks are discussed. A new method of utilizing a large box (3 X 13 X 31 inches) in a medication cart is described. The box is made of one-quarter inch cardboard and waxed. It is replaced daily and incinerated. The system is time-saving, economical, and should reduce the number of needlesticks. 相似文献
57.
Mary J. Christoph Vivienne M. Hazzard Elina Järvelä-Reijonen Laura Hooper Nicole Larson Dianne Neumark-Sztainer 《Journal of nutrition education and behavior》2021,53(3):240-245
ObjectiveAssess how intuitive eating relates to dietary intake.MethodsSurvey data were collected in Project Eating and Activity in Teens and Young Adults, the fourth wave of a longitudinal cohort study (weighted n = 1,830, 49% women; mean age = 31 years). Intuitive eating was assessed using a 7-item scale adapted from the Intuitive Eating Scale and Intuitive Eating Scale-2. Dietary intake was measured via a semiquantitative food frequency questionnaire. Mean servings were stratified by gender and intuitive eating quartiles and adjusted for sociodemographic characteristics and caloric intake.ResultsWomen and men in the top intuitive eating quartile consumed 0.6–0.3 servings more fruit and 0.4–0.6 servings more vegetables daily, respectively, compared with the bottom quartile, whereas men in the top quartile also consumed 0.6 servings fewer whole grains (all P < 0.05) than the bottom quartile.Conclusions and ImplicationsIntuitive eating shows promise as a healthier alternative to practices such as dieting. 相似文献
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