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51.
We report a case in which mosaicism of trisomy 13 was detected in 4/10 cells (40 per cent) in amniotic fluid cell cultures, followed by a low rate of mosaicism (1/160 cells) detected in a fetal blood sample. This finding presents a dilemma both for the genetic counsellor and for the parents in determining whether or not to terminate the pregnancy.  相似文献   
52.
Over a 4-year period, 14 dyskaryotic fetuses were diagnosed by amniocentesis, performed after early detection of malformations using transvaginal sonography (TVS). These 14 dyskaryotic fetuses were detected out of 4878 sonographic screenings performed by TVS between 9 and 16 weeks' gestation. Twenty-eight per cent of the referrals were at high risk and 72 per cent were at low risk for fetal malformations. Two hundred and twenty-nine fetuses (4.7 per cent) of the screened population had 265 anomalies, 39 per cent of them being transient. In 7 of the 14 dyskaryotic fetuses (50 per cent), the sonographically detected anomalies were transient, being undetected by follow-up sonographic screenings at later gestational ages (⩾18 weeks). Postponing the first sonographic scan aimed at malformation detection to a later gestational age may lead to transient anomalies and their associated dyskaryosis being missed.  相似文献   
53.
Out of 13 252 cases in which fetal bilateral echogenic kidneys were detected by transvaginal sonography between 12 and 18 weeks' gestation, there were nine fetuses where oval hypoechogenic masses were detected in the renal bed. In five fetuses where hypoechogenic masses in the renal bed were sonographically visualized, postabortal examination was compatible with renal agenesis and the hypoechogenic masses proved to be enlarged adrenals. In three additional cases, unilateral renal agenesis was accompanied by unilateral enlarged adrenals, radiologically confirmed postnatally. In one case, a false-positive sonographic diagnosis of Potter syndrome was made because of bilateral hypoechogenic masses in the renal bed. Postabortal examination detected hypoplastic kidneys, but of normal histology, in a dyskaryotic fetus with trisomy 22. In four cases of renal agenesis, the amniotic fluid was of normal volume until the 17th week. In two of the five cases of Potter syndrome, a cystic structure, compatible with the urinary bladder, was detected in the pelvis at 14 weeks. The diagnostic criteria for renal agenesis in the early fetus differ from those used in the second half of gestation.  相似文献   
54.
Two fetuses with heart abnormalities were detected by transvaginal sonography at 14 weeks of gestation. In the first fetus, a ventricular septal defect and an overriding aorta were detected and a diagnosis of tetralogy of Fallot was suggested. In addition, cystic hygroma and omphalocoele were visualized and the cytogenetic study revealed trisomy 18. In the second fetus, ventricular septal defect, pericardial effusion, and omphalocoele were detected.  相似文献   
55.
The presence of chorio-amniotic separation and amnion anomalies was recorded in 9500 patients referred for vaginal ultrasound examination at 14.5–16 weeks' gestation. In all patients with a change in the amnion, a search for fetal anomalies was performed and pregnancy outcome was checked. Amnion dysmorphism was observed in 30 cases. The main findings were a floating membrane which changed its configuration when the uterus was tilted and multiple intrauterine amniotic sheets. In no case was attachment of the fetus to the membranes noted. There was no fetal abnormality and pregnancy outcome was favourable in all patients. In conclusion, ultrasound visualization of amnion dysmorphism in early pregnancy is not associated with an adverse pregnancy outcome.  相似文献   
56.
Prior to a relocation of a governmental organization in Israel, 155 workers responded to a questionnaire tapping three criteria: the intention to relocate, positive feelings, and stress reactions. The questionnaire also addressed potential correlates: biographical data, family-related variables, perceived attitudes of co-workers, job satisfaction and centrality, and anticipations regarding work and nonwork aspects. The intention to relocate was associated mainly with the perceived attitude of the spouse and the children. Stress experienced was most strongly related to the future job prospects, and the positive emotions were mostly correlated with the perceived favourability of the anticipated changes. The family-related variables were found to be significantly correlated with all the criteria. These results suggest that organization should direct efforts on spouse and children in order to influence employees' decisions and feelings regarding relocation. This and other implications are discussed.  相似文献   
57.
The harvesting of communal natural resources by ‘outsiders’ (i.e. harvesters from other villages or towns) was investigated in ten rural villages in South Africa. Participatory Rural Appraisal (PRA) techniques were used to collect data in focus groups in each village. A case study quantifying the outflow of fuelwood was also conducted in one of the villages. Harvesting by outsiders was reportedly widespread and, in the case of fuelwood, a cause for concern. Of 13 recorded resources, the three most commonly harvested by outsiders were fuelwood, plants for traditional medicine and river sand for brick-making. An increase in harvesting by outsiders over the last decade was widely reported. This was related to socio-economic changes, largely associated with the first democratic elections in 1994. Key socio-economic drivers of this increased harvesting were: 1) the breakdown of institutional control of resources, 2) rising unemployment, and 3) a pervasive sense of entitlement associated with new-found political freedom and democracy. Evidence suggests that the increased harvesting by outsiders is a reality, rather than a xenophobic accusation, and that it poses a threat to the sustainability of communal resources in rural areas. This is discussed within the context of South Africa as a society in transition.  相似文献   
58.
Chemical fractionation of phosphorus in stabilized biosolids   总被引:2,自引:0,他引:2  
Three chemicals-ferrous sulfate (FeSul), calcium oxide (CaO), and aluminum sulfate (alum)-were applied at different rates to stabilize P in fresh, anaerobically digested biosolids (FBS) obtained from an activated sewage treatment plant. A modified Hedley fractionation procedure was used to assess P forms in these sludge-borne materials and in a biosolids compost (BSC) prepared from the same FBS. Each biosolids material exhibited a unique pattern of P distribution among fractions. The most available P forms, namely: (i) water-soluble P (WSP); (ii) membrane-P; and (iii) NaHCO(3)-P, were stabilized by small rates of each of the chemicals; but the P transformation into more stable forms depended on the type of chemical added. The stabilized P forms were enhanced by high rates of CaO and FeSul, but were reduced by high rates of alum. The organic P (P(o)) in the first three fractions of the FeSul- and alum-stabilized biosolids was enhanced by the chemical addition, and P(o) transformation from NaOH-P(o) into NaHCO(3)-P(o) was found in calcium-stabilized biosolids. A positive relationship was found between NaHCO(3)-P(o) and the NaHCO(3)-extracted organic C in all chemically stabilized biosolids. One-step extraction by NaHCO(3) or NaOH underestimated P extraction compared to the stepwise extraction. The reported results are consistent with solid-state P speciation reported earlier and contribute important information for optimizing biosolids stabilization to reduce P loss after incorporation in soils and for maximizing soil capacity to safely store pre-stabilized biosolids.  相似文献   
59.
Holoprosencephaly is a cerebral anomaly resulting from incomplete cleavage of the primitive prosencephalon or forebrain. Early detection of this anomaly is very important since the most severe form is incompatible with life. The diagnosis also signals the need for a chromosomal determination since chromosomal abnormalities have been associated with this anomaly. An early diagnosis of alobar holoprosencephaly at 14 weeks' gestation, employing transvaginal sonography, is reported. Our findings are compared with prenatal transabdominal sonographic findings of holoprosencephaly which have been reported during the last decade in the literature.  相似文献   
60.
A study of 6350 consecutive transvaginal ultrasound examinations was performed as part of a routine fetal evaluation. Twenty-one cases (0.33 per cent) of early second-trimester sonographic detection of minor renal abnormalities (unilateral renal agenesis, pelvic kidney, and double collecting system) are presented. The sonographic diagnosis was made at 14–18 weeks of pregnancy and confirmed, in all of the 21 fetuses, postnatally or by post-mortem. A high incidence of associated fetal anomalies (24 per cent) and parental renal abnormalities (14 per cent) was demonstrated. Transvaginal sonography was found to be a useful tool for diagnosing these renal anomalies as early as 14 weeks of pregnancy. The likelihood of various associated anomalies and long-term implications on renal function raise questions concerning the prenatal management of such patients.  相似文献   
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