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41.
Pregnancy outcomes after increasing maternal serum alpha-fetoprotein levels   总被引:1,自引:0,他引:1  
Five hundred sixty women among 35,787 screened had an initial maternal serum alpha-fetoprotein (MSAFP) of 2.5 or more multiples of the median. They were divided into three groups: group 1, 2.5-2.9; group 2, 3.0-3.9; and group 3, over 4.0 multiples of the median. These groupings determined the relationship to adverse pregnancy outcome, defined as fetal death, fetus with significant anomalies, and prematurity/growth retardation. The overall risk of adverse outcome after an initial elevation was 38%, after excluding pregnancies with incorrect dates or multiple gestations with levels below 4.5 multiples of the median: 27, 39, and 45% in groups 1, 2, and 3, respectively. This risk rose to 86% for levels over 6.0 multiples of the median. There was a significant positive correlation between abnormalities and death detected with ultrasound and amniocentesis and those indicated by increasing MSAFP levels: 10, 20, and 31% in groups 1, 2, and 3, respectively. After normal ultrasound and amniocentesis studies, there was a trend toward increasing risks for fetal death after 20 weeks between groups 2 and 3 (5 and 11%), but not for growth retardation/prematurity (12, 17, and 13%). After an elevated MSAFP, the overall risk of a late pregnancy complication after normal ultrasound and amniocentesis was 22%: 19, 23, and 25% in groups 1, 2, and 3, respectively. This figure increased to 67% for levels above 6.0 multiples of the median.  相似文献   
42.
80.2 Per cent of 111 Down syndrome pregnancies had anmiotic fluid (AF) alpha fetoprotein (AFP) levels on or below the median and 10.8 per cent at or below 0.5 MoM compared with 41.9 and 1.4 per cent of controls. These differences were even more striking when the gestational age was less than 18 weeks compared with greater than or equal to 18 weeks. No such association was seen for other chromosome abnormalities including trisomy 18,45,X and mosaics, 47,XXY,47,XXX, and other structural abnormalities and triploidy, even when high levels due to defects such as omphalocele and cystic hygroma were excluded. All cases of trisomy 13 and 80 per cent with 47,XYY had AF-AFP levels above the median. Selection of cases for karyotyping by a low level of AF-AFP would clearly fail to detect aneuploidies other than Down syndrome and is not recommended. A possible weak association between low maternal serum (MS) and AF-AFPs in Down syndrome was most evident at less than 18 weeks, suggesting that MS screening between 16 and 18 weeks may be the most informative time.  相似文献   
43.
PURPOSE: To describe the visual complaints of a series of patients implanted with the AcrySof(R) (Alcon Surgical) acrylic intraocular lens (IOL) that resolved with IOL exchange. SETTING: Jules Stein Eye Institute, Los Angeles, California, and John A. Moran Eye Center, Salt Lake City, Utah, USA. METHODS: This was a retrospective review of patients who had AcrySof IOL exchange from January 1997 to December 1998. RESULTS: Eight patients (9 eyes) with bothersome visual symptoms following AcrySof IOL implantation were identified. Problems included glare, halos around point light sources, and peripheral arcs of light, often worse at night. In each case, the IOL was well-centered in the capsular bag and there was no significant posterior capsule opacification. Six patients (7 eyes) had the MA30BA model with a 5.5 mm optic, and 2 patients (2 eyes) had the MA60BM model with a 6.0 mm optic. No extralenticular reasons for the patients' complaints could be identified. Exchanging the AcrySof IOLs with silicone or poly(methyl methacrylate) IOLs alleviated most symptoms. In 5 of 8 patients, dysphotopsias resolved completely. CONCLUSIONS: A small number of patients implanted with AcrySof IOLs have specific complaints of glare, halos, and peripheral arcs of light. Optical considerations that may help explain these symptoms include the high refractive index of the IOL material and the truncated design of the optic. Patients who are highly observant and those with large pupils may be particularly symptomatic. Intraocular lens exchange may be necessary in some cases.  相似文献   
44.
PURPOSE: A 1986-1987 survey found 8.8% prevalence of open-angle glaucoma in the black population of St. Lucia, West Indies. This follow-up study assessed visual field loss progression in untreated glaucoma patients and glaucoma suspects 10 years later. DESIGN: Cohort study. METHODS: Subjects were 205 glaucoma patients and suspects; 1987 data included age, sex, visual acuity, and visual fields measured by automated threshold perimetry (Humphrey C 30-2 test), and 1997 data included intraocular pressure, visual acuity, and visual fields measured by the same test. Exclusion criteria included field unreliability, field improvement due to vision improvement, nonglaucomatous vision deterioration, glaucoma treatment since 1988, and scoring of a visual field as end stage in 1987. Visual fields were scored by algorithms for the Advanced Glaucoma Intervention Study (AGIS) and Collaborative Initial Glaucoma Treatment Study (CIGTS). RESULTS: By AGIS criteria, 55% of 146 right eyes and 52% of 141 left eyes showed progression of visual field loss. In linear regressions, progression severity was unassociated with sex, intraocular pressure, or baseline visual field score, but was positively associated with age (P <.001, right; P =.002, left). The cumulative probability of reaching end stage in 10 years in at least one eye was approximately 16% by AGIS criteria. By CIGTS criteria, 73% of 146 right eyes and 72% of 141 left eyes progressed. CONCLUSIONS: These data provide a unique opportunity to study progression of untreated glaucoma. The percentage of eyes showing visual field loss progression and the percentage reaching end stage were considerably higher than in studies of visual field progression in treated eyes.  相似文献   
45.
Baboval T  Crandall JE  Kinnally E  Chou DK  Smith FI 《Glia》2000,31(2):144-154
Glycoconjugates bearing the epitope 3-fucosyl-N-acetyllactosamine (CD15) are believed to be involved in cell-cell interactions and are temporally and spatially regulated in the brain. In the rat postnatal cerebellum, CD15 is predominantly expressed in the molecular layer by Bergmann glial cells, but little CD15 expression is seen in other astroglia, and the basis for this restricted expression is not known. Adenoviral vectors were shown to efficiently deliver transgenes to cerebellar glial cells and were used to determine whether manipulation of glycosyltransferase activities could enhance the expression of CD15 in these cells. In dissociated cerebellar cell cultures, few glial cells normally express CD15. However, transduction of these cells with an adenoviral vector (AdGFPCMVFucT) that expressed both green fluorescent protein (GFP) and FLAG-tagged rat alpha 1, 3-fucosyltransferase IV (rFuc-TIV) resulted in high CD15 expression on the surface of all transduced glial cells. Likewise, infection of cerebellar slice cultures caused the appearance of CD15-positive transduced cells of glial cell morphology in the internal granule cell layer. Thus, enhancement of Fuc-T activity caused robust CD15 expression in cerebellar glial cells that normally show little expression of CD15, suggesting a role for Fuc-T levels in regulating CD15 expression in this cell type. The manipulation of levels of glycosyltransferases using adenoviral vectors may prove a useful tool to investigate questions of glycoconjugate regulation in glial cells in the developing rodent cerebellum.  相似文献   
46.
47.
The Aarskog syndrome in three brothers   总被引:1,自引:0,他引:1  
A sibship is reported of three brothers who all manifested short stature and identical facial, digital, and genital anomalies consistent with Aarskog's syndrome. In addition, all manifested ophthalmoplegia and growth delay of prenatal onset, features uncommon among patients previously reported with this syndrome. The mother had some of the digital anomalies seen in her three boys, but otherwise was unaffected. The pattern of inheritance seen in our family and in those previously reported indicates that the syndrome is either X-linked recessive or autosomal dominant, with limited expression in the female.  相似文献   
48.
The purpose of this study was to examine reports of adherence to oral medications, parent-child concordance in reports of adherence, and factors associated with poor adherence in adolescents with inflammatory bowel disease (IBD). Participants were 50 children with IBD 11 to 17 years of age and their parents. Parents completed an adherence interview and the Child Behavior Checklist, Family Assessment Device, and demographics questionnaires. Separately, adolescents completed the adherence interview and the Piers Harris Self-Concept Scale, Children's Depression Inventory, and Coping Strategies Inventory questionnaires. The treating gastroenterologists of participating children completed the Pediatric Crohn's Disease Activity Index during a clinic visit within a week of completion of the questionnaires. Mean parent- and child-reported adherence scores fell between the "most of the time" and "always" categories, although perfect adherence was low. Among IBD-specific medications (5-ASAs, immunomodulators, steroids), 48% of children and 38% of parents reported being always adherent to all medications. Parent-child concordance was high. Family dysfunction and poor child coping strategies were associated with worse adherence. The correlation between more behavioral/emotional problems and lower adherence approached significance. Adherence should be monitored in families that lack appropriate child discipline and in children who cope by simply wishing stressors would go away. Because these issues are associated with poor adherence, it has been suggested that psychotherapy addressing these areas may contribute to improved adherence.  相似文献   
49.
50.
A sample and hold amplifier system has been described which is capable of eliminating stimulus artifacts from a variety of biological recordings which would otherwise be impossible to interpret during electrical stimulation. Factors contributing to the prolongation of stimulus artifact are discussed in relation to the design requirements of this system. The application of this artifact suppression circuit to monitoring EEG seizures during electrical stimulation is demonstrated.  相似文献   
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