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981.
Min Chen Dr Yung Hang Lam Chen Lung Lin Kwok Wah Chan Pui Wah Hui Mary Hoi Yin Tang Chin Peng Lee Pek Lan Khong 《黑龙江环境通报》2002,22(12):1067-1070
Enteric duplication cyst is a congenital abnormality that is believed to arise from abnormal recanalization of the bowel during embryogenesis. Previous reports suggest that the condition may be suspected prenatally by sonographic demonstration of an intra-abdominal cystic mass in the second and third trimesters. We present the sonographic features of a fetus with ileal duplication cyst at 12 weeks of gestation, which show that the condition may present in the first trimester of pregnancy. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
982.
Soybeans (Glycine max. cv. Williams) were grown to maturity in soil columns within polyvinyl pipe and placed in greenhouses with charcoal filtered (CF) and nonfiltered (NF) air. In each greenhouse plants were grown with and without soil moisture stress (SMS). Targeted soil water potentials at 0.25 m for no SMS and between 0.45 and 0.60 m for the SMS regime were -0.05 and -0.45 M Pa, respectively. The 7 h (1000-1700 h EDT) mean O(3) concentrations (June-October) were 0.039 and 0.009 ppm in NF and CF air, respectively. Ozone and SMS in combination were less than additive in their effects on growth of the plant top and bean yields. Plants in CF air had 70% greater top weight, 58% more bean yield and 43% more root dry weight than in NF air. Both the plant and the seed weight from plants without SMS weighed 35% more than with SMS. Total root length in CF air for plants with and without SMS averaged 1.84 and 1.98 km, respectively, as compared to 1.59 and 1.66 km for plants with and without SMS in NF air. The resultsare different, so far as the combined effects of O(3) and SMS on yield and root growth are concerned, than in a similar field study by Heggestad and co-workers primarily because of the presence of a water table in the field but absence of it in the columns, as planned, in this experiment. It is unique to use large soil columns to study root distribution and length as related to the effects of ambient O(3) alone, and its combination with SMS. 相似文献
983.
984.
We report one case of a familial complex chromosomal rearrangement (CCR) involving four different chromosomes 5, 10, 16 and 18. The CCR was detected prenatally at 20 weeks' gestation because of advanced maternal age and history of recurrent miscarriages. Cytogenetic analysis of cultured amniotic fluid cells with GTG banding showed a 46,XX,t(5;16;10;18)(q13;q22;q11.2;q21) karyotype. Parental cytogenetic study revealed that the mother has the same CCR. RBG banding, high-resolution banding and fluorescence in situ hybridization (FISH) were used to characterize further and confirm the conventional banding data. No physical abnormalities were shown in the targeted fetal ultrasonography examination. The parents decided to continue the pregnancy. The child is now 2 years old and has neither congenital anomalies nor evidence of delayed psychomotor development. The fetal targeted ultrasound and FISH analysis helped us reassure fetal status. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
985.
986.
987.
988.
H.W. Tyrer E.T. Cantrell R. Horres I.P. Lee W.B. Peirano R.M. Danner 《Environment international》1981,5(4-6)
In this study we examined the effect of diesel exhaust (DE) exposure on the disposition of a typical polycyclic aromatic hydrocarbon. DE-exposed and nonexposed A/Jax mice were divided into three groups and each mouse instilled intratracheally with benzo[a]pyrene (BaP). One group (A) received 14C-BaP, and at intervals of 2, 24, and 168 h, three mice from the group were killed and quick frozen for whole body autoradiography. Sagittal sections were cut at 0.5 mm intervals and autoradiograms prepared. Adjacent sections were studied so that radioactive areas were matched to specific organs. The second group (B) received 3H-BaP and at 2, 24, and 168 h these mice were killed. Livers, lungs, and testes were weighed and frozen. From these tissues metabolites were analyzed; these data are reported in the next paper. Histofluorescent examination of tissues from mice instilled with nonradioactive BaP (group C) confirmed that BaP was present in the lung. The autoradiography data are the basis for elucidating the BaP distribution in the mouse. Within 2 h after instillation radioactivity was detected in the entire animal, with most in lungs, liver, and GI tract. By 24 h after instillation considerable radioactivity had redistributed to the GI tract. At 168 h after instillation only a trace of label was found in the GI mucosa. 相似文献
989.
We have determined feasibility and levels of agreement for visualizing the nuchal translucency within a time limit with three-dimensional (3D) and two-dimensional (2D) transvaginal ultrasound. A total of 213 women of median gestational age 13 weeks (range 11–14 weeks) undergoing first-trimester nuchal translucency (NT) thickness measurements with 2D transabdominal ultrasound were included in the study. Additionally all women underwent 2D and 3D transvaginal NT examination within a time limit of 90 s. These two methods were compared with each other and with our standard method (2D transabdominal ultrasound) with respect to visualization of fetal nuchal fold and to the levels of agreement. The nuchal fold was visualized by 3D and 2D transvaginal ultrasound in 85.9% (95% CI: 80.5%, 90.3%) and 25.8% (95% CI: 20.1%, 32.2%), respectively (p<0.001). There was a statistically significant underestimation of the NT by 2D transabdominal as compared with 3D transvaginal ultrasound of 0.1 mm (p<0.001), and by 3D transvaginal as compared with 2D transvaginal ultrasound of even 0.1 mm (p<0.001). 3D transvaginal ultrasound of the nuchal fold has increased feasibility to 2D transvaginal ultrasound within a short examination time and with minimal, but significant, measurement differences. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
990.
Whales repetitively dive deep to feed and should be susceptible to decompression syndrome, though they are not known to suffer the associated pathologies. Avascular osteonecrosis has been recognized as an indicator of diving habits of extinct marine amniotes. Vertebrae of 331 individual modern and 996 fossil whales were subjected to macroscopic and radiographic examination. Avascular osteonecrosis was found in the Oligocene basal odontocetes (Xenorophoidea) and in geologically younger mysticetes, such as Aglaocetus [a sister taxon to Balaenopteridae + (Balaenidae + Eschrichtiidae) clade]. These are considered as early "experiments" in repetitive deep diving, indicating that they independently converged on their similar specialized diving physiologies. 相似文献