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81.
Val A. Catanzarite MD Ph.D. David B. Schrimmer Cynthia Maida Art Mendoza 《黑龙江环境通报》1995,15(3):229-235
The sinusoidal fetal heart rate pattern has been described in association with severe fetal anaemia, with fetal hypoxaemia, and with the administration of parenteral narcotics. Here, we report a case of decreased fetal movement in which a sinusoidal tracing was recorded. The sonographic diagnosis of a massive fetal intracranial haemorrhage was made. A non-interventive approach was taken and the fetus died soon after in utero. We review 28 previous cases in which the prenatal sonographic diagnosis of fetal intracranial haemorrhage was made, including the underlying maternal and fetal factors and neonatal outcomes. We propose that the sinusoidal tracing in this case was due to the intracranial bleed and suggest that fetal intracranial haemorrhage be considered in the sonographic evaluation of the fetus with a sinusoidal pattern. 相似文献
82.
83.
David M. Sherer MD James R. Woods Jr Jacques S. Abramowicz John A. Dipreta Leon A. Metlay Richard Jaffe 《黑龙江环境通报》1993,13(12):1079-1084
Although malignant transformation of fetal cervical teratoma is extremely rare, perinatal morbidity is high and usually related to the size of the tumour, which may compromise fetal swallowing and subsequently lead to upper airway obstruction. We present a case in which mid-trimester serial sonography demonstrated markedly rapid early growth of a lesion of this type between 17 and 19 weeks' gestation indicating the aggressive nature of this tumour, assisting parental decision to terminate the pregnancy. Histopathology confirmed grade 3 immaturity of the lesion. 相似文献
84.
In a retrospective survey, the incidence of neural tube defects in liveborn trimsomy 18 was found to be 6·2 per cent. Based on these data one would expect to find trisomy 18 in 1 of the 117 patients with myeloidysplasia; the incidence of trisomy 18 in dysraphic fetuses would be anticipated to be higher. These observations underscore the need for amniocentesis karyotyping of fetuses with neural tube defects, and the importance of careful examination of infants born with neural tube defects. 相似文献
85.
Gamergates (i.e. mated reproductive workers) are mostly known from ant species within the Ponerinae. We report here the discovery of gamergates in two species of the subfamily Myrmicinae. Until now, mated reproductive females in colonies of myrmicine species have been considered morphologically distinct from the worker caste. However, in two species of the myrmicine Metapone (Metapone madagascarica and a newly discovered, not yet described Metapone species) all workers have six ovarioles and a spermatheca; and some of them are mated. There are no morphological differences between mated and non-mated workers. Field observations and laboratory studies indicate that colonies of the Metapone species can reproduce with gamergates only. 相似文献
86.
Although amphibians are highly vocal, they generally emit only a limited number of acoustic communication signals. We report here the extraordinarily rich vocal repertoire of Amolops tormotus, a ranid species in China. These frogs produce countless vocalizations, some of which share features of birdsong or primate calls, e.g., ultrasonic frequency components, multiple upward and downward FM sweeps, and sudden onset and offset of selective harmonic components within a call note. Frame-by-frame video analysis of the frog's calling behavior suggests the presence of two pairs of vocal sacs that may contribute to the remarkable call-note complexity in this species. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s00114-002-0335-x. 相似文献
87.
Aysen Müezzinoğlu Tolga Elbir Abdurrahman Bayram 《Environmental Engineering and Policy》1998,1(2):109-116
In this study, an inventory of air pollutant emission estimates from major air polluting sources in Turkey for period between 1985 and 2005 with 5-year intervals were estimated. Inventory covers anthropogenic sources of five major air pollutants of particulate matter, sulfur dioxide, carbon monoxide, nitrogen oxides and non-methane volatile organic compounds. Their break-down with respect to main activity sectors were shown and their distribution by the largest industrial source categories were worked out as annual estimates. This inventory and its analysis point to serious environmental implications of air pollutants and a need to develop a policy plan for reducing these emissions. 相似文献
88.
Vanessa M. Barnabei MD PhD David A. Krantz James N. Macri John W. Larsen Jr 《黑龙江环境通报》1995,15(12):1131-1134
We have applied our multimarker approach of maternal serum alpha-fetoprotein (AFP) and free-beta human chorionic gonadotropin (hCG) for Down syndrome screening to multiple gestations to assess its efficacy for improved detection of twin and triplet pregnancies. This study matched 225 cases of twin pregnancy and 39 cases of triplet pregnancy each with ten singleton pregnancies based on gestational week, race, time to receive sample, time of year of sample, and geographical area. The ratios of the MOM for each group at the tenth, 50th, and 90th percentiles were compared by the Wilcoxon test. Risks for twins were calculated using Bayes' rule, the age-related incidence of twins, and the levels of AFP and free-beta hCG. The tenth, 50th, and 90th percentiles of free-beta hCG MOMs in twin and triplet cases were 0.85, 1.99, and 4.51, and 1.38, 2.78, and 4.07, respectively. For AFP, the MOMs at these percentiles were 1.26, 1.91, and 2.99, and 2.02, 2.68, and 5.30, respectively. The twin and triplet distributions for each marker were statistically significantly different from the singleton distributions (P<0.0001) and from each other (P=0.0012). At a twin risk cut-off of 1 in 50, 77.4 per cent of all twin gestations can be detected in a second-trimester AFP and free-beta hCG screening protocol with 5.1 per cent of singleton pregnancies falsely identified as at risk for twins. Our dual marker protocol for mid-trimester pregnancy screening combining AFP and free-beta hCG can identify over 77 per cent of twin pregnancies in women less than 35 years of age. This benefit may contribute to an improved outcome of pregnancy by early detection of multiple gestation. 相似文献
89.
长江,嘉陵江重庆城区段二维水质对流扩散数学模型 总被引:6,自引:0,他引:6
对二水质对流扩散数学模型的有限差分解作了较详细的叙述,同时对距离步长,时间步长计算,网络内水深,流速,横向扩散系数的求取也作了简要介绍。 相似文献
90.
James N. Macri Kevin Spencer David Aitken Kenneth Garver Philip D. Buchanan Françoise Muller Andre Boue 《黑龙江环境通报》1993,13(7):557-562
Maternal serum free beta (hCG) levels are elevated (median 2·20 MOM) in the first trimester of pregnancy in 38 Down syndrome cases as compared with appropriate controls. This observation may form the basis for its use as a marker in screening for Down syndrome in the first trimester. Altered levels of the free beta analyte are observed in pregnancy conditions or complications other than Down syndrome. 相似文献