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The aim was to assess the role that fetal bladder size has in the determination of fetal hydronephrosis. Forty-three fetuses were evaluated for fetal hydronephrosis in the second trimester of pregnancy. Anteroposterior measurements of the renal pelvis were obtained with a full bladder and again when the bladder emptied in each fetus. Statistical analysis was performed using the Spearman rank order correlation coefficient to assess the relationship between bladder status and renal dilation. The anteroposterior size of the fetal renal pelvis diminished from 6.8 ± 1.8 mm on a full bladder scan to 4.5 ± 1.6 mm when the bladder was emptied (P<0.001). Fifty-three per cent of the fetuses whose renal pelvic measurements were 5 mm or more on a full bladder scan had normal-appearing renal pelvises when their bladders emptied. The status of the fetal bladder should be considered when evaluating fetal hydronephrosis.  相似文献   
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The world is moving toward efforts to reduce net greenhouse gas emissions. Reduction efforts may involve the agricultural sector through options such as planting of trees, altering crop and livestock management, and increasing production of biofuels. However, such options can be competitive with domestic food production. In a free trade arena, reduced domestic food production could stimulate increased production and exports in other countries, which are not pursuing net emission reductions. As a consequence, emission reduction efforts in implementing countries may be offset by production increases stimulated in other countries. We examine the competitive effects of agriculturally related emission reduction actions on agricultural production and international trade. In doing this, we employ the assumption that U.S. emission reduction caused cost increases will also occur in other reducing countries. We consider emission reduction: 1) unilaterally by the U.S., 2) by all Kyoto Protocol Annex B countries, and 3) globally. The results, which are only suggestive of the types of effects that would be observed due to the simplifying cost assumptions, indicate compliance causes supply cutbacks in regulated countries and increases in non-regulated countries. The study results show that producers in regulating countries are likely to benefit and consumers lose due to commodity price increases. Seniority of Authorship is shared among the first three authors.  相似文献   
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Three test-series were applied, which differed in regard to the basal medium (natural or artificial sea water, salinity level, addition of detergent); the culture conditions (primary cultures, subcultures, back-inoculations into basal medium without toxic metals); the criterion employed (zoospore activity, sporangia development, or dry weight of Thraustochytrium striatum Schneider). The temperature applied was 18° to 20°C. The sea water-pollen-method (MWP) proved to be the most suitable: it is simple and more sensitive than the other tests; subcultures and back-inoculations are possible without much additional work; conditions simulate nature; first results are available after 3 to 4 days. The SMS-method (enriched natural sea water of different salinities) provides additional information on salinity effects. Nine substances have been tested: (CH3COO)3Hg, HgCl2, CdCl2·H2O, ZnSO4 ·7H2O, NiSO4·7H2O, CuSO4·5H2O, CoCl2·6H2O, MnCl2 ·4H2O, and phenol. In regard to their toxicity these substances can be divided into 2 groups: Hg- and Cd-salts inhibit development down to greater dilutions than the remainder; Zn and Ni seem to yield intermediate effects. Salinity modifies the toxic effects of the test substances. In higher salinities, comparable concentrations of test substances reveal stronger inhibitory effects than in lower salinities. Detergents may augment the toxic effects, at least of CuSO4. The marine lower fungus T. striatum is a useful organism for testing biological consequences of water pollutants.  相似文献   
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