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81.
Cholera in Portugal, 1974.I. Modes of transmission 总被引:4,自引:0,他引:4
PA Blake ML Rosenberg JB Costa PS Ferreira CL Guimaraes EJ Gangarosa 《Canadian Metallurgical Quarterly》1977,105(4):337-343
In April-November 1974, Portugal had a cholera epidemic caused by Vibrio cholerae El Tor Inaba with 2467 bacteriologically confirmed hospitalized cases and 48 deaths. Most of the country was affected, with 17 of the 18 districts reporting cases. V. cholerae was isolated from 42 per cent of shellfish tested during the epidemic, and an epidemiologic study found that a history of consumption of raw or poorly cooked cockles was significantly more common among cholera patients than among paired controls. Water from a spring and a brand of commercially bottled water were also found to be vehicles of transmission of cholera. Although night soil was sometimes used on gardens, consumption of raw fruits and vegetables was not associated with illness. 相似文献
82.
83.
101 Samoans living in New Zealand, of whom 77 had no known non-Samoan ancestry, have been typed for nine blood group systems, four serum protein and 23 red cell enzyme systems, for haemoglobin variants and antigens at the HLA A nad B loci. The frequencies of genes in these various systems suggest that Samoans fall partly into an island Melanesian-Micronesian pattern, and partly are unique. Their uniqueness is most distinctive for the HLA system. 相似文献
84.
The nature of the damage structure in neutron-irradiated zirconium has been studied using transmission electron microscopy. The damage structure consists of dislocation loops with Burgers vectors. No evidence was found for component dislocation loops. The dislocation loops are non-edge in character and are elliptical with the loop minor axis in the (0001) plane and the major axis in the vicinity of the [0001] direction. This ellipticity was particularly marked for large vacancy loops whereas interstitial loops tended to be circular. Under all irradiation conditions studied, the loop populations were mixed interstitial/vacancy. 相似文献
85.
Tested 9 deaf and 9 normal 15-27 yr olds on their ability to report letters, shapes, and nonsense figures from a tachistoscopic presentation. Deaf Ss performed worse than hearing Ss on recall of figural information, thereby supporting a linguistic coding hypothesis. However, there was no difference between the groups on position information, and letter confusions were primarily visual in both groups. Findings suggest that more attention should be given to visual short-term memory in theoretical models of memory. Formation of the icon was apparently not affected by a linguistic deficit, since effects of stimulus duration and type of viewing (continuous vs interrupted) were similar in both hearing and deaf Ss. Significant positive correlations which were found between deaf Ss' school reading scores and their tachistoscopic scores were not interpreted as support for a linguistic coding hypothesis, but rather as support for the notion that the memory skills tested in the experiment may underlie reading ability. (French summary) (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Blake Brian F.; Perloff Robert; Zenhausern Robert; Heslin Richard 《Canadian Metallurgical Quarterly》1973,58(2):239
32 male undergraduates, with high and low scores on S. Budner's (see record 1964-08477-001) measure of intolerance of ambiguity, judged the newness of products varying systematically in atypicality and reported their willingness to buy them. The more intolerant Ss perceived the atypical products as newer than did tolerant Ss. Perceived product newness tended to be positively related to willingness to buy among tolerant Ss, but negatively related among intolerant ones. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
RA Bruce T DeRouen DR Peterson JB Irving N Chinn B Blake V Hofer 《Canadian Metallurgical Quarterly》1977,39(6):833-840
In a follow-up study of 1,852 men with coronary heart disease, 195 deaths occurred within the first 3 years (33 +/- 13 months [mean +/- standard deviation]). Analysis of these cases indicated that the risk of sudden cardiac death in ambulatory men with clinical manifestations of coronary heart disease may be readily estimated from noninvasive clinical and exercise criteria. The important predictors are indexes of the severity of coronary heart disease and impairment of peak left ventricular function demonstrated with symptom-limited maximal exercise. The advantages of these predictors are that they may be elicited on the initial study as well as on follow-up noninvasive examinations of ambulatory patients. The appearance of nonelectrocardiographic predictors in serial examinations may provide an indication for invasive studies and be a more important finding than the ischemic S-T reponse to exertion. 相似文献
88.
It was predicted that significantly more volunteering would occur when test Ss observed the invitation (to participate in an experiment) being accepted prior to their being asked than would occur in the control condition (where S had no opportunity to observe the behavior of others in the invitation situation); and significantly less when refusal was observed, as compared with the control condition. The results support the predictions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
An experiment with 90 college Ss. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
The possibility of using a fluorescent probe technique for the study of drug-providone (I) interactions was investigated. 1-Anilino-8-naphthalenesulfonate (II) was used as the probe. Sulfanilamide, sulfacetamide, and sulfabenzamide were used as the binding competitors. Both sulfacetamide and sulfabenzamide decreased the fluorescence intensity of the I-II complex, while sulfanilamide increased the intensity. The fluorescence depression was greater with sulfabenzamide than with sulfacetamide, indicating that the former is more strongly bound to povidone. Since sulfabenzamide has a greater hydrophobic group (phenyl) than sulfacetamide (methyl), the binding of these sulfonamides to povidone is probably at least partially hydrophobic in nature. The enhanced fluorescence intensity of the I-II complex in the presence of sulfanilamide is believed to involve hydrogen bonding in which the sulfanilamide acts as an intermediary between I and II. Double reciprocal plots for the I-II and sulfonamide-I interactions were employed to obtain a binding constant of 3.2 X 10(4) M-1 for the I-II interaction. The association constants for sulfacetamide and sulfabenzamide were calculated by means of the Klotz equation to be 13.4 and 56.8 M-1, respectively. The povidone molecules appear to have 1.28 binding sites for these compounds under the experimental conditions. 相似文献