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51.
52.
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   
53.
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   
54.
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   
55.
We report two second trimester pregnancy terminations in the same woman following intrauterine ultrasonic findings of hydrops fetalis, polyhydramnios, lack of fetal movements, and short, fixed malformed limbs. One fetus also showed a cystic mass at the back of the head. Radiographic and anatomic studies of the fetuses demonstrated multiple pterygia, flexion contracture of multiple joints, abnormal facial appearance, cleft palate, pulmonary hypoplasia, and gracile bones. The cystic mass of the back of the head was found to be a cystic hygroma. These findings are consistent with the lethal variant of multiple pterygium syndrome. Early prenatal diagnosis of this condition is possible using ultrasonography.  相似文献   
56.
Ultrasonographic prenatal diagnosis of congenital diaphragmatic hernia is well established, but the correlation of prenatal detection with clinical outcome remains unclear. We report our experience with 15 cases of prenatally diagnosed congenital diaphragmatic hernia. Seven fetuses were detected at 14–16 weeks' gestation; two with a normal sonographic study at 15 and 16 weeks' gestation showed visceral herniation at 21 and 23 weeks, respectively. In the remaining six cases, a diaphragmatic hernia was found at ultrasonography after 24 weeks' gestation, while previous sonographic studies had been normal. All seven fetuses in whom a diaphragmatic hernia was diagnosed before 16 weeks' gestation were aborted; four of them had severe malformations or karyotype abnormalities. The two neonates who were diagnosed at 21 and 23 weeks' gestation died after surgical repair. In contrast, all six infants whose visceral herniation was diagnosed after 24 weeks of gestation, and whose sonographic studies at 15–23 weeks had been normal, are alive and well after corrective surgery. The results of this series suggest that the timing of visceral herniation into the thoracic cavity is a major indicator of the prognosis of these fetuses and that herniation that occurs after 25 weeks of gestation carries a favourable clinical outcome. Normal sonographic studies during the first half of pregnancy do not exclude the subsequent development of congenital diaphragmatic hernia, raising questions about the advisability of repeat examinations at later stages of gestation.  相似文献   
57.
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   
58.
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   
59.
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   
60.
The large number of radio frequency (RF) transmitters employed in modern marine platforms requires that they operate in mutual coexistence while posing no danger to operators and equipment despite the limited available physical space. A key to the successful system integration is the control of the electromagnetic environment on the ships’ topsides, which might pose radiation hazards (RADHAZ) to personnel (HERP). HERP are caused by transmitter antenna installations that generate intentional EM radiation in excess of the safe levels in zones of personnel activity. Radiation safety to personnel is achieved when the average radiation power density is below the permissible exposure limits (PEL) for HERP at locations of personnel activity and medical equipment operation. This paper describes the analysis tools and techniques for the evaluation of HERP on marine platforms. The same approaches could be employed in the analysis of land site antenna deployment scenarios.  相似文献   
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