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61.
In order to determine the outcome and associated chromosomal and structural anomalies in fetuses diagnosed in utero as having a congenital diaphragmatic hernia, we reviewed 48 consecutive cases referred to our regional Fetal Diagnostic Unit between 1988 and 1995. All babies were delivered in units with appropriate neonatal resuscitation facilities. Thirteen babies [34 per cent of those tested, confidence interval (CI) 19-49 per cent] had karyotypic abnormalities. Three had trisomies but the other nine had more complex karyotypic abnormalities including translocations, deletions, and marker chromosomes. Twenty-one fetuses (44 per cent, CI 30-58 per cent) had additional ultrasound abnormalities which affected the heart in ten cases (21 per cent). Overall, 13 babies survived (27 per cent, CI 14-40 per cent). In babies with normal chromosomes and no additional structural abnormalities the survival rate was 50 per cent (CI 25-75 per cent). Poor outcome was not predicted by early gestation at diagnosis, the hernial contents, or the presence of polyhydramnios. We conclude that parents should be counselled about prognosis with information derived from series of prenatally diagnosed diaphragmatic hernias. The investigations offered should include a detailed ultrasound examination, particularly of the heart, and karyotyping by fetal blood sampling. 相似文献
62.
63.
Yukinobu Fukushima Shin’ichi Arakawa Masayuki Murata 《Photonic Network Communications》2006,11(2):151-161
We deal with the problem of designing the logical topology in IP-over-WDM networks. Many conventional methods for designing
the logical topology assume that a constant number of wavelengths will be available on each fiber. But it is not necessary
to utilize all wavelengths on each fiber in building an effective logical topology on a WDM network. Instead, several wave-bands
may be considered for introduction while deploying additional wave-bands and their corresponding optical amplifiers when additional
wavelengths are actually required. In this case, the number of wavelengths available on the respective fibers depends on the
number of optical fiber amplifiers deployed on each fiber. In this paper, we propose a heuristic algorithm for the design
of a logical topology with as few optical fiber amplifiers as possible. Our results indicate that our algorithm reduces the
number of optical fiber amplifiers with a slight increase of average packet delays. 相似文献
64.
Hagiwara N. Suzuki Y. Murase H. 《IEEE transactions on instrumentation and measurement》1992,41(1):98-101
A method of improving the resolution and accuracy of incremental type rotary encoders using a phase encoding and code compensation system is described. Applying this system to an optical incremental encoder whose scale pitch is 1/3600 rotation, results in a resolution of up to 1/920000 rotation, and better than ±1/300000 rotation (±0.0012°) precision is obtained 相似文献
65.
Congenital syphilis has been diagnosed very seldom in ancient populations. The case that we examined comes from San Jeronimo's Church (17th and 18th centuries AD; Mexico City). Coffin 43 contained an incomplete skeleton of an approximately 2-year-old infant. The pathological lesions of this skeleton include bilateral osteochondritis, diaphyseal osteomyelitis, and osteitis and/or periostitis on the long bones. The radiographic appearance depicts symmetrical osteomyelitic foci, particularly at the proximal extremity of both tibiae (Wimberger's sign). The skull exhibits hydrocephaly and periosteal changes on the vault, and the unerupted upper incisors evince dental hypoplasia and other pathological alterations reminiscent of Hutchinson's incisors. All these features strongly suggest a case of early congenital syphilis. 相似文献
66.
67.
The basic analitical method for so-called expression operation, the separation of liquid from solid-liquid systems by compression, are presented in view of the flow through compressible porous media. It has become evident that the expression mechanism consists of two flow phenomena. These types of phenomena can be analyzed by consideration of the flow mechanism through compressible porous beds, first by the filtration theory and second by the so-called consolidation theory. A simplified equation is also presented. It is shown that the simplified equation is well applicable to industrial expression problems even when the creep effects of matarials to be expressed are appreciable 相似文献
68.
69.
A patient with chronic idiopathic mediastinal fibrosis (MF) without concomitant retroperitoneal fibrosis is reported. He presented with pleuritis, malaise and pain and stiffness in the thoracic spine. During the 3.5 years of observation no clinical signs of obstruction of adjacent visceral structures in the chest cavity have developed. The diagnosis was made by CT, X-rays of the chest remained normal throughout the observation period, except for thickening of the involved pleura. The administration of high doses of oral corticosteroids did not appear to influence either clinical symptoms or the manifestations of MF as seen by CT. 相似文献
70.
Preliminary investigations for the interactions between surfaces of polymers and water were conducted by the measurements of contact (θ) and sliding-angles (α) with water. Work of adhesion (W) and interaction energies were subsequently calculated by using the values of θ and α, respectively. For the evaluation of actual performances of polymeric materials, shear strength of ice adhesion and snow accretion were measured. Characteristics of homogeneous surfaces of polymers in the interaction with water were obtained. On the basis of these concepts, the materials with heterogeneous surfaces were synthesized. Results of surface characterizations in these polymers showed that the relationship between θ and α, and the other surface attributes are very different according to polymer systems. The surface controlled energetically and morphologically, and the superior hydrophobic property prevented the snow accretion, but not ice adhesion. On the other hand, the organopolysiloxane modified with lithium compound provided the lowest strength of ice adhesion, but a poor capability of snow repellency. In the structural and energetic viewpoints', interactions between heterogeneous surfaces and water (snow and ice) were discussed. For the theoretical prediction, the intermolecular energies between model polymers and water were calculated by using a molecular orbital SCF method. The order of interactions calculated were coincident with experimental values deduced from α, but not from θ. The advantage of heterogeneity of surface was supported by the theoretical understanding. © 1994 John Wiley & Sons, Inc. 相似文献