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41.
We report the findings of a cross-sectional epidemiologic study of Giardia lamblia and Cryptosporidum infections in Jamaica. Three hundred twenty eight stool samples from patients less than one to 81 years of age were examined using formalin-ether concentration for G. lamblia, Zeihl-Neelsen staining for Cryptosporidium, and the Prospect rapid enzyme immunoassay (EIA; Alexon, Sunnyvale, CA) for parasite diagnosis. The Prospect Giardia rapid assay detected 17 cases of G. lamblia infection compared with six by formalin-ether concentration. However, the Prospect Cryptosporidum EIA did not increase the rate of detection of Cryptosporidum when compared with Zeihl-Neelsen staining. Cryptosporidum infections were most frequently diagnosed in children less than five years old and prevalence decreased with age. In contrast, the prevalence of giardiasis increased as children became older. There were no associations between the infections and stool consistency, clinical manifestations, or sex of the individuals. The contribution of the parasites to childhood morbidity will depend on accurate laboratory diagnosis. 相似文献
42.
Tymchuk Alexander J.; Drapkin Robin; Major-Kingsley Susan; Ackerman Andrea B.; Coffman Elizabeth W.; Baum Maureen S. 《Canadian Metallurgical Quarterly》1982,13(3):412
Discusses the inadequacy of old, and the lack of new guidelines for the protection of the rights of individuals in psychological treatment. A questionnaire containing vignettes of clinical and research situations that required decision-making processes was completed by 113 members of the Division of Clinical Psychology of the American Psychological Association. Data suggest that there is inconsistency in decision making. Suggestions for improving the decision-making process and enhancing consistency are presented. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
L Weing?rtner I Richter R Patsch HH Thiemann W Br?mme W Baum U Vorwald 《Canadian Metallurgical Quarterly》1977,147(2):186-198
Various dates on amoxicillin (resorption, distribution, elimination, tissue passage, urinary excretion) are presented. The bacterial spectrum is more fully discussed. Amoxicillin is compared with ampicillin. Dosage and therapeutical results are presented. Within repeated bronchoscopic examinations necessary on account of bronchopulmonary affections determination of germs were done in 88 children. At the same time examination of ampicillin levels in bronchial secretions were performed after amoxicillin therapy with different high doses (3 x 125 mg to 3 x 750 mg) for 7 days. It could be shown that good antibiotic levels could be found in secretion specimens above all obtained 2 to 4 hours after the last amoxicillin administration. They could be found too, if there did not exist any purulent secretion or stronger inflammation. There are relations between the amount of dosage, the level in secretion as well as the influence on germs. 相似文献
44.
Performed 2 experiments in an automated 1-way avoidance box for rats. Exp. I, with 44 Sprague-Dawley female albino rats, was concerned with the effect of shock intensity on the rate of extinction using the massing-of-trials technique during extinction. Most measures of avoidance learning were not affected by shock intensity, and the rate of extinction was also not significantly affected. Exp. II, with 44 Ss similar to those in Exp. I, examined the effect of the duration of the extinction ITI on the rate of extinction. A critical duration is suggested by results. (French summary) (15 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Reports an error in "Alpha-adrenergic receptors in hypothalamus for the suppression of feeding behavior by satiety" by D. L. Margules (Journal of Comparative & Physiological Psychology, 1970[Oct], Vol 73[1], 1-12; see record 1971-03588-001). On page 3, paragraph 1 of the Method section, the angle of implantation of cannulas was 6° from the perpendicular; in paragraph 2 of the Method section, the following sentence was omitted: All rats were maintained on a reversed dark-light cycle (lights off at 0800 hr. and on at 2000 hr. EST) and were drugged in the dark. On page 10, paragraph 6, line 10 of the Discussion section, "abolishes" should read "enhances." In "Precocious mating in male rats following treatment with androgen or estrogen" by Michael J. Baum (Journal of Comparative & Physiological Psychology, 1972[Mar], Vol. 78[3], 356-367; see record 1972-22393-001), on page 367 the date of receipt should read August 24, 1970. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
A multichannel reservation-based channel-access protocol is investigated in this paper. The available system bandwidth is
divided into distinct frequency channels. Under the protocol, one channel (the control channel) is used to exchange reservation messages and the remaining channels (the traffic channels) are used for information-bearing traffic. The performance of this scheme is compared to that of a single-channel
reservation-based protocol. A simple contention-based slotted-Aloha protocol is also considered. Performance results take
into account the effects of multiple-access interference on acquisition and packet errors. Results show that the reservation-based
approach is advantageous under conditions of high traffic. In addition, a pacing mechanism that mitigates multiple-access
interference and promotes fairness is described, and results are presented that demonstrate its effectiveness.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
47.
Sensitivity of the backscattering Mueller matrix to particle shape and thermodynamic phase 总被引:1,自引:0,他引:1
The Mueller matrix (M) corresponding to the phase matrix in the backscattering region (scattering angles ranging from 175 degrees to 180 degrees) is investigated for light scattering at a 0.532-microm wavelength by hexagonal ice crystals, ice spheres, and water droplets. For hexagonal ice crystals we assume three aspect ratios (plates, compact columns, and columns). It is shown that the contour patterns of the backscattering Mueller matrix elements other than M11, M44, M14, and M41 depend on particle geometry; M22 and M33 are particularly sensitive to the aspect ratio of ice crystals. The Mueller matrix for spherical ice particles is different from those for nonspherical ice particles. In addition to discriminating between spherical and nonspherical particles, the Mueller matrix may offer some insight as to cloud thermodynamic phase. The contour patterns for large ice spheres with an effective size of 100 microm are substantially different from those associated with small water droplets with an effective size of 4 microm. 相似文献
48.
An efficient finite element (FE) scheme to deal with a class of coupled fluid-solid problems is presented. The main ingredients of such methodology are: an accurate Q1/P0 solid element (trilinear in velocities and constant piecewise-discontinuous pressures); a large deformation plasticity model; an algorithm to deal with material failure, cracking propagation and fragment formation; and a fragment rigidization methodology to avoid the possible numerical instabilities that may produce pieces of material flying away from the main solid body. All the mentioned schemes have been fully parallelized and coupled using a loose-embedded procedure with a well-established and validated computational fluid dynamics (CFD) code (FEFLO). A CSD and a CFD/CSD coupled case are presented and analyzed. 相似文献
49.
50.
Daniel R. Baum John R. Wallace Michael F. Cohen Donald P. Greenberg 《The Visual computer》1986,2(5):298-306
An efficient algorithm is introduced for the production of realistic image sequences of dynamic environments. The practicality of the radiosity method, which computes the interreflection of light within complex diffuse environments independent of viewpoint, is extended to dynamic environments where the paths of moving objects have been predefined. The algorithm takes advantage of the object coherence between static portions of an environment. A preprocessing stage executes once for a given image sequence and precalculates constant geometrical relationships in the environment. When the environment geometry changes, an update stage determines the global illumination using information provided by the preprocessor and the current positions of all moving objects. Test environments show speedups of at least twenty-five times over previous radiosity methods. 相似文献