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排序方式: 共有776条查询结果,搜索用时 15 毫秒
41.
R J Wapner J L Simpson M S Golbus J M Zachary D H Ledbetter R J Desnick S E Fowler L G Jackson H Lubs R J Mahony 《Prenatal diagnosis》1992,12(5):347-355
Cytogenetic data from the United States NICHD collaborative study of chorionic villus sampling (CVS) were used to evaluate the clinical significance of chorionic mosaicism. The 10,754 patients with normal cytogenetic results were compared with 108 patients (1.0 per cent) with placental mosaicism and 181 patients (1.6 per cent) with pseudo-mosaicism. Of the pregnancies intended to continue, the pregnancy loss rate was significantly greater in patients with placental mosaicism than in the cytogenetically normal cohort (8.6 vs. 3.4 per cent, p less than 0.05). However, there was no difference in the frequencies of abruptio placenta, preterm labour or delivery, small-for-gestational-age newborns, pregnancy-induced hypertension, or neonates with Apgar scores less than 7. 相似文献
42.
Oxygen saturation (SaO2) during sleep and pulmonary functions were evaluated in 19 infants with congenital heart disease, aged 6 +/- 4 months, and in 11 normal infants, aged 8 +/- 5 months, to determine whether infants with congenital heart disease have more frequent oxygen desaturation during sleep and, if so, its relationship to underlying pulmonary function. Infants with congenital heart disease were classified as acyanotic (n = 11) or cyanotic (n = 8) on the basis of their aortic SaO2 at the time of cardiac catheterization (greater or less than 90% SaO2). Pulmonary function tests included respiratory rate, functional residual capacity, total respiratory system compliance, and maximal flows at functional residual capacity. Significant differences were found in the values for the lowest SaO2 of each 5-minute epoch (SaO2L) averaged during the entire sleep time (normal 94% +/- 2%, acyanotic 90% +/- 3%, and cyanotic 74% +/- 4%; p less than 0.01). The three groups also differed significantly in frequency distributions of percentage of total sleep time with SaO2L less than 90% (SaO2%T) (normal 10% +/- 17%, acyanotic 36% +/- 34%, and cyanotic 97% +/- 4%; p less than 0.05). Compared with the control group, the acyanotic group had a higher respiratory rate (66 +/- 19 breaths/min vs 35 +/- 6 breaths/min; p less than 0.01), a lower tidal volume (65% +/- 29% predicted vs 105% +/- 18% predicted; p less than 0.01), and a lower total respiratory compliance (59% +/- 18% predicted vs 106% +/- 30% predicted; p less than 0.01). A negative correlation existed between SaO2%T and aortic SaO2 (R2 = 0.64; p less than 0.01). We conclude that oxygen desaturation occurs during sleep in infants with congenital heart disease; the presence of desaturation appears to be related to the initial degree of hypoxemia and the presence of abnormal pulmonary function. 相似文献
43.
B S Mahony R A Filly P W Callen M S Golbus 《American journal of obstetrics and gynecology》1985,152(1):63-68
Amniotic band syndrome causes a variety of fetal malformations involving the limbs, craniofacial region, and trunk. Six prenatally diagnosed cases of amniotic band syndrome are discussed. The diagnosis was based on sonographic visualization of either amniotic sheets or bands associated with fetal deformation or deformities in nonembryologic distributions known to characterize the amniotic band syndrome. Seven additional cases are considered in which an aberrant sheet of tissue with a free edge was visualized within the amniotic cavity but no restriction of fetal motion or subsequent deformity was demonstrated. 相似文献
44.
Tubal factor infertility: an association with prior chlamydial infection and asymptomatic salpingitis 总被引:8,自引:1,他引:8
In 265 Canadian women, with and without tubal factor infertility (TFI), we compared Chlamydia trachomatis cultures of endocervical swabs, endotubal swabs and biopsies, serology, and past history. A history of pelvic inflammatory disease (PID) was absent in 69.2% of TFI women, despite visual evidence of tubal damage. C. trachomatis was not isolated in any of 52 patients with TFI (TFI group), 114 having tubal ligation (STER group), or 99 patients having hysterectomy (HYST group). However, chlamydial antigen was detected with an immunochemical method in 1 of 16 tubal biopsy specimens from TFI women. The prevalence of chlamydial IgM or IgG antibody in serum was significantly higher (P less than 0.0001) in the TFI group (79.1%) than in the other two groups (relative odds, 6.3; 95% confidence interval: 2.5, 16.8). In seropositive (IgG or IgM) subjects, there was a significant (P = 0.003) and strong (relative odds, 5.1; 95% confidence interval: 1.5, 18.1) association between chlamydial IgA antibody and TFI. In women with TFI, there was no significant association between IgM or IgG seropositivity (P = 0.56). or IgA seropositivity (P = 0.53), and a negative history for PID. These findings are consistent with the hypothesis that C. trachomatis is a major cause of TFI following PID, which may or may not be asymptomatic. 相似文献
45.
Mechanisms of gastro-oesophageal reflux were studied by oesophageal manometry and pH monitoring in 33 children: nine controls, 15 with gastro-oesophageal reflux alone, and nine with reflux oesophagitis. A total of 122 episodes of reflux were analysed in detail: 82 (67%) were synchronous with swallowing and 40 (33%) asynchronous. Infants with trivial symptoms had gastro-oesophageal reflux synchronous with swallowing, whereas those with serious symptoms had slower acid clearance and asynchronous reflux. There were significant differences in lower oesophageal sphincter pressure and amplitude of oesophageal contractions between controls and patients with both gastro-oesophageal reflux and reflux oesophagitis. In reflux oesophagitis there was a decrease in lower oesophageal sphincter pressure and the contractions had a bizarre waveform suggesting a neuropathic process. 相似文献
46.
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49.
Ninety-one children with nocturnal enuresis or enuresis plus daytime urgency incontinence were studied by cystometry. Seventy-two per cent of the girls and 62 per cent of the boys had evidence of bladder instability. Sixty-eight children in whom abnormalities were found on preliminary voiding urodynamics or voiding cystourethrography also underwent calibration and endoscopic examination under anesthesia. An atropine-suppression test was also performed preoperatively in some children with a markedly unstable bladder demonstrated on preoperative cystometry. In the majority of children tested suppression of bladder instability with atropine was demonstrable. Voluntary detrusor sphincter dyssynergia was demonstrated in a majority of the children with daytime urgency incontinence. Sixty-five per cent of the boys and 81 per cent of the girls were treated for urethral obstructive lesions suspected to be of functional urodynamic significance. Postoperative cystometry showed marked improvement in bladder stability in 57 per cent of the girls and 63 per cent of the boys treated for suspected urethral obstructive pathology. The anticholinergic suppression test was found to have no significant predictive value relative to the cause or surgical curability of bladder instability. The pathophysiologic significance of overactivity of integral voiding reflexes 6 through 11 is described. 相似文献
50.