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OBJECTIVE: To establish reference intervals for the fetal right, left and total lung volumes and heart volume between 12 and 32 weeks of gestation. METHODS: Fetal lung and heart volumes were measured using three-dimensional (3D) ultrasound in 650 normal singleton pregnancies at 12-32 weeks. The VOCAL (Virtual Organ Computer-aided AnaLysis) technique was used to obtain a sequence of six sections of each lung and the heart around a fixed axis, each after a 30 degrees rotation from the previous one. The rotation axis for the lungs extended from the apex to the upper limit of the diaphragm dome, and the rotation axis for the heart extended from its apex to its connection to the great vessels. The contour of each of these organs was drawn manually in the six different rotation planes to obtain the 3D volume measurement. In 60 cases the fetal lungs and heart volumes were measured by the same sonographer twice and also by a second sonographer once in order to compare the measurements and calculate intra- and interobserver agreement. RESULTS: The total lung volume and heart volume increased with gestation, from respective mean values of 1.6 and 0.6 mL at 12 weeks to 10.9 and 4.3 mL at 20 weeks and 49.3 and 26.6 mL at 32 weeks. The right to left lung volume ratio did not change significantly with gestation (median, 0.7), whereas the heart to total lung volume ratio increased with gestation from about 0.3 at 12 weeks to 0.5 at 32 weeks. In the Bland-Altman plot, the difference between paired measurements by two sonographers was, in 95% of the cases, less than 0.05, 0.5 and 1.9 mL for each lung at 12-13, 19-22 and 29-32 weeks, respectively, and the corresponding values for the heart volumes were 0.04, 0.4 and 2.3 mL. CONCLUSIONS: In normal fetuses the lung and heart volumes increase between 12 and 32 weeks of gestation. The extent to which in pathological pregnancies possible deviations in these measurements from normal prove to be useful in the prediction of outcome remains to be determined.  相似文献   
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OBJECTIVE: To establish reference intervals with gestation for the right and left lung areas and lung area to head circumference ratio (LHR). METHODS: This was a cross-sectional study of 650 normal singleton pregnancies at 12-32 weeks of gestation. We measured the left and right lung areas on the cross-sectional plane of the thorax, used for examination of the four-chamber view of the heart, by three different techniques: firstly, manual tracing of the limits of the lungs; secondly, multiplication of the longest diameter of the lung by its longest perpendicular diameter; thirdly, multiplication of the anteroposterior diameter of the lung at the mid-clavicular line by the perpendicular diameter at the midpoint of the anteroposterior diameter. RESULTS: The respective mean left and right lung areas (manual tracing) increased with gestational age, from 36 and 58 mm(2) at 12 weeks to 220 and 325 mm(2) at 20 weeks and 594 and 885 mm(2) at 32 weeks. This 16-fold increase in lung area was accompanied by a four-fold increase in head circumference. Consequently, the left and right LHR increased with gestational age. The most reproducible way of measuring the lung area was by manual tracing of the limits of the lungs and the least reproducible was by multiplying the longest diameter of the lungs by their longest perpendicular diameter. Furthermore, the method employing the longest diameter, compared with the tracing method, overestimated both the left and the right lung areas by about 45% and the method employing the anteroposterior diameter overestimated the area of the right lung by about 35%, but not that of the left lung. CONCLUSIONS: In the antenatal prediction of pulmonary hypoplasia by the assessment of lung area it is important to take gestational age into account. Dividing the lung area by the head circumference does not correct for the gestation-related increase in lung area. Reproducible measurement of the lung area is provided by manual tracing of the limits of the lungs, rather than by multiplication of lung diameters.  相似文献   
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Four hundred and eight respondents, who did or did not know persons close to themselves with alcohol problems, from four different racial/ethnic groups (with one group, Filipinos, categorized in terms of whether they were born in the Philippines or in the US.) rated the importance of 19 different causes of problem alcohol use and 22 different means of overcoming problem alcohol use. Rank-order correlations across sexes, persons differing in exposure to problem drinkers, and ethnic groups were nearly all in the 0.90's regarding causation. Correlations of Caucasians' ratings with those of other groups were high, but only in the 0.60's and 0.70'9, chiefly because Caucasians were more prone to regard problem alcohol use as hereditary and as a disease, and less likely to believe problem use to result from social factors. All across-group correlations concerning beliefs about the effectiveness of means of overcoming problems were in the 0.90's. Some of the means of treatment regarded most highly by all groups have not been demonstrated to be effective.  相似文献   
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We used the species specificity and repetitious nature of subtelomeric kinetoplastida sequences to generate a duplex PCR assay for the simultaneous detection of Trypanosoma cruzi and Trypanosoma rangeli in experimentally and naturally infected triatomine (Reduviid) bugs and in infected human subjects. The assay was species specific and was capable of detecting 1/20th of T. cruzi and 1/4th of T. rangeli cell equivalents without complementary hybridization. In addition, the PCR-based assay was robust enough for direct application to difficult biological samples such as Reduviid feces or guts and was capable of recognizing all T. cruzi and T. rangeli strains and lineages. Because the assay primers amplify entirely different target sequences, no reaction interference was observed, facilitating future adaptation of this assay to an automated format.  相似文献   
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Hepatic steatosis is a major risk factor in ischemia-reperfusion. The present study evaluates whether preconditioning, demonstrated to be effective in normal livers, could also confer protection in the presence of steatosis and investigates the potential underlying protective mechanisms. Fatty rats had increased hepatic injury and decreased survival after 60 minutes of ischemia compared with lean rats. Fatty livers showed a degree of neutrophil accumulation and microcirculatory alterations similar to that of normal livers. However, in presence of steatosis, an increased lipid peroxidation that could be reduced with glutathione-ester pretreatment was observed after hepatic reperfusion. Ischemic preconditioning reduced hepatic injury and increased animal survival. Both in normal and fatty livers, this endogenous protective mechanism was found to control lipid peroxidation, hepatic microcirculation failure, and neutrophil accumulation, reducing the subsequent hepatic injury. These beneficial effects could be mediated by nitric oxide, because the inhibition of nitric oxide synthesis and nitric oxide donor pretreatment abolished and simulated, respectively, the benefits of preconditioning. Thus, ischemic preconditioning could be an effective surgical strategy to reduce the hepatic ischemia-reperfusion injury in normal and fatty livers under normothermic conditions, including hepatic resections, and liver transplantation.  相似文献   
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Résumé L'évidement axillaire peut être envisagé soit à titre préventif et systématique dans la chirurgie du cancer ou à titre curatif dans les affections du contenu de la fosse axillaire. Sa réalisation opératoire doit tenir compte de la morphologie de la lame cellulo-adipeuse de l'aisselle, moulée autour du paquet vasculo-nerveux entouré de sa gaine et de l'importance de ses prolongements vers le creux sus-claviculaire, voie de passage des courants lymphatiques.La position opératoire du membre supérieur facilite l'abord de la base de la pyramide et l'exérèse totale de son contenu sans sacrifice cutané ou musculaire et sans séquelle motrice.Le repérage des divers éléments de la lame cellulo-adipeuse doit permettre à l'anatomo-pathologiste d'apprécier la localisation exacte des ganglions lymphatiques.  相似文献   
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Neuregulin 1 (NRG1) is one of the most exciting candidate genes for schizophrenia since its first association with the disorder in an Icelandic population. Since then, many studies have analyzed allele and haplotype frequencies in European and Asian populations in cases and controls yielding varying results. We investigated the association of NRG1 with psychosis in a total sample set of 575 individuals from 151 Spanish nuclear families. We tested eight SNPs across 1.2 Mb along NRG1 including regions previously associated to schizophrenia in association studies. After correction for multiple testing, the TDT analysis for each marker did not show a significant over-transmission of alleles from the parents to the affected offspring for any of the markers (P > 0.05). The haplotypic analysis with TRANSMIT and PDT did not show preferential transmission for any of the haplotypes analyzed in our sample. These results do not seem to suggest that the investigated NRG1 markers play a role in schizophrenia in the Spanish population, although the finding of a trend for association with one SNP in the 3'of the gene warrants further investigation.  相似文献   
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