Search Results
Results 301 - 350 of 622
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Bortolus R - - 1999
On the basis of MEDLINE and manual searches, we examined the main papers in the English literature regarding risk factors for spontaneous (i.e. not related to fertility drug use) multiple births. The constant frequency of monozygotic (MZ) pregnancies over time and in different geographical areas suggests that the determination of ...
Ulrich V - - 1999
We studied the genetic influence on cause of migraine with aura (MA) by analyzing a twin population. The twin sample consisted of 2,026 monozygotic (MZ) twins and 3,334 same-sex dizygotic (DZ) twins, born from 1953 to 1960, from the population-based New Danish Twin Register. A validated questionnaire was used to ...
Weinzweig J - - 1999
Any animal model of a human congenital anomaly established by iatrogenic methods involving intrauterine fetal manipulation has limited clinical applicability. A congenital model that more closely simulates the etiopathogenesis of a human anomaly may provide data that can more readily be extrapolated to that anomaly and, therefore, be used in ...
Bulmer M - - 1999
Galton greeted Darwin's theory of pangenesis with enthusiasm, and tried to test the assumption that the heredity particles circulate in the blood by transfusion experiments on rabbits. The failure of these experiments led him to reject this assumption, and in the 1870s he developed an alternative theory of heredity, which ...
Hershlag A - - 1999
OBJECTIVE: To determine the effect of mechanical assisted hatching on the pregnancy rate (PR). DESIGN: A retrospective comparative analysis of hatched versus nonhatched consecutive assisted reproductive technology (ART) cycles. SETTING: A hospital-based ART program. PATIENT(S): Patients undergoing ART treatment with assisted hatching (1994-1996) were compared with patients who did not ...
Sugar M - - 1999
The multiple functions of clothes include utility, protection, rivalry, disguise, camouflage, display for seduction purposes, aggression, totemism, and status. Here the focus is on a decorative and distinctive hierarchical aspect of ancient dress, the tsitsit or fringes, whose original function is long absent, but that has endured for 3,500 years ...
Cannon T D - - 1999
A number of lines of evidence converge in implicating neurodevelopmental processes in the etiology and epigenesis of schizophrenia. In this study we used a prospective, longitudinal design to examine whether adverse obstetric experiences predict schizophrenia and whether there is a deviant functional-developmental trajectory during the first 7 years of life ...
Mealey L - - 1999
Symmetry is a major correlate of physical attractiveness across species, including humans. Investigating the nature of this relationship has been difficult, however, for several reasons, including the facts that variance in symmetry is attributable to more than one source and is often correlated with other variables related to attractiveness. This ...
Geddes J R - - 1999
Several epidemiological studies have reported an association between complications of pregnancy and delivery and schizophrenia, but none have had sufficient power to examine specific complications that, individually, are of low prevalence. We, therefore, performed an individual patient meta-analysis using the raw data from case control studies that used the Lewis-Murray ...
Stassen H H - - 1999
In an electroencephalographic (EEG) study of 27 pairs of monozygotic (MZ) twins discordant for schizophrenia, 13 pairs of MZ twins concordant for schizophrenia, 40 pairs of healthy MZ twins, and 91 healthy, unrelated subjects with repeated assessments, we investigated (a) the trait quality of brainwave patterns with respect to interindividual ...
McNeil T F - - 1999
Many authors have suggested that theoretically the labor-delivery complications (LDCs) that frequently appear in the histories of individuals with schizophrenia represent the secondary consequence of preexistent abnormality in the fetus. The question of whether LDCs are systematically associated with prenatal complications and fetal abnormality was studied in 70 singleton schizophrenia ...
Ninio J - - 1999
In the Poggendorff illusion, two colinear segments abutting obliquely on an intervening configuration (often consisting of two long parallel lines) appear misaligned. We report here the results of a component analysis of the illusion and several of its variants, including in particular the 'corner-Poggendorff' illusion, and variants with a single ...
Lichtenstein P - - 1998
Previous research has provided evidence for a genetic effect in monozygotic twinning, indicated by an increased risk for monozygotic women to have monozygotic offspring. However, since the biological mechanism for this trait is unknown, it is not clear if there exists a paternal inheritance. In this study we investigated twin ...
Fredell L - - 1998
PURPOSE: Hypospadias is a common urogenital malformation in boys. The etiology is unknown but genetic and environmental factors are involved. Because monozygotic twins have the same genetic constitution, we studied disease discordant twin pairs to evaluate environmental risk factors while controlling for genetic effects. MATERIALS AND METHODS: We used questionnaires ...
van Dyck C H - - 1998
BACKGROUND: The apolipoprotein E (Apo E) epsilon4 allele has been associated with parietal metabolic abnormalities and asymmetries in asymptomatic subjects at risk for Alzheimer disease (AD). However, previous research has shown minimal effect of the epsilon4 allele on regional cerebral blood flow (rCBF) and metabolism in patients with probable AD. ...
Ohara K - - 1998
1. Several studies on monozygotic twins discordant for schizophrenia showed that the cerebral ventricle-brain ratio (VBR) was larger in the twins with schizophrenia, as compared with the corresponding normal twins. 2. The results suggest that the difference of the VBR of the discordant twins was larger than that of the ...
Meldrum D R - - 1998
Our purpose was to examine the benefits of assisted hatching in our program and to determine whether the procedure increases the implantation of nonviable embryos or monozygotic twinning. Consecutive in vitro fertilization cycles using assisted hatching were compared with historical controls. The impact of assisted hatching was analyzed according to ...
Rodríguez-Pinilla E - - 1998
The question of whether systemic use of corticosteroids during the first trimester of pregnancy increases the risk of congenital malformations in people has still not been resolved. Here, we present the results of a case-control study on the relationship of corticosteroids during pregnancy and oral clefts in the newborn infant. ...
Kates W R - - 1998
In this study, we investigated the neuroanatomical similarities and differences between a pair of monozygotic, 7.5-year-old twin boys discordant for strictly defined autism, to identify neuroanatomical pathways that are impaired in individuals with autism. Although the unaffected twin did not fulfill the traditional diagnostic criteria for autism, he displayed constrictions ...
Lapter M - - 1998
The aim of this study was to establish prevalence of hypodontia in the twin sample and to assess the degree of its heritability. A study was performed in a sample of 96 twin pairs, 38 pairs being monozygotic (MZ) and 58 pairs dizygotic (DZ), from north-west Croatia. The sample included ...
Degitz S J - - 1998
Retinoic acid (RA) is teratogenic in many species and is an effective inducer of cleft palate in mice. The pathogenesis of cleft formation varies with the timing of exposure. It has been demonstrated, before formation of the palatal shelves, that RA exposure results in insufficient mesenchymal tissue, and palatal shelves ...
Duffy D L - - 1998
In complex diseases of genetic etiology such as asthma and atopy, it is difficult to differentiate causes of disease from consequences, and quantitate the importance of such causative factors. We examined possible risk factors for the development of wheezing and bronchial hyperresponsiveness in a cotwin-control study nested within a larger ...
Czeizel A E - - 1998
OBJECTIVE: To study human teratogenic risk of metronidazole. DESIGN: A case-control analysis of congenital abnormalities after oral metronidazole treatment during pregnancy grouped by months of gestation. The source of information concerning the use of drugs during pregnancy was the prospective data of the women's prenatal logbook and the retrospective data ...
Finch C E - - 1998
The prezygotic hypothesis considers the possibility that development is subject to environmental influences on the oocyte prior to conception. Such influences may occur in the maternal grandmother's uterus where oogenesis is completed or in the mother before fertilization. According to this hypothesis, the separate eggs from which DZ twins are ...
Jones P B - - 1998
OBJECTIVE: The 1966 North Finland general population birth cohort was studied to determine whether abnormalities during pregnancy, delivery, and the neonatal period are associated with adult-onset schizophrenia. METHOD: The authors included all 11,017 subjects alive in Finland at age 16. For each individual, standardized assessments made during pregnancy, delivery, and ...
Mäkikyrö T - - 1998
Developmental deviance is known to be associated with schizophrenia. We tested the hypothesis that the most severe schizophrenia requiring treatment with clozapine would particularly show these effects. Therefore, associative factors from pregnancy, delivery, neonatal and socio-demographic characteristics were compared between the clozapine-treated schizophrenic cases (n = 17) and the remaining ...
Selten J P - - 1998
There is evidence of an increased incidence of schizophrenia in Afro-Caribbean immigrants to the UK and in Surinamese- and Dutch Antillean immigrants to The Netherlands. We tested the hypothesis that second-trimester exposure to the 1957 A2 influenza pandemic, which swept through the Caribbean in the same period as it affected ...
Corey L A - - 1998
The role of genetic factors in determining risk for status epilepticus (SE) was examined in twins identified using the population-based Virginia Twin Registry. Concordance rates for SE were 0.38 for monozygotic (MZ) and 0.00 for dizygotic (DZ) twins, with the rate in MZs being significantly increased over DZs. The prevalence ...
Wright L - - 1998
The speech and language therapy profession is committed to the use of outcome measurement to maximise both efficiency and efficacy. However, measuring change in adult stuttering therapy is particularly problematic. It is proposed that outcomes of therapy should include stuttering behaviours, reactions to stuttering and handicap resulting from stuttering. Current ...
Ashworth C J - - 1998
The extent of embryo mortality is usually estimated by the difference between the numbers of corpora lutea and embryos in the same animal, which assumes that each corpora lutea represents one potential embryo. Recent observations from the authors' laboratory reveal situations in which the number of embryos exceeds the number ...
Labrune P - - 1997
Six fetuses with normal chromosomes were found to have severe craniofacial, limb, and visceral malformations during the second trimester of pregnancy. Two of these fetuses were monozygotic twins while a third one had a healthy dizygotic twin brother. A case with familial recurrence was also observed. Autopsy and skeletal radiographs ...
Charlemaine C - - 1997
OBJECTIVE: To examine twin similarities on biparietal diameter (BPD) measurements by zygosity (monozygotic [MZ] and dizygotic [DZ]) and chorionicity (monochorionic [MC] and dichorionic [DC]) and their evolution during pregnancy. METHOD: A sample of 54 pairs of twins (43 DZ sets, 11 MZ sets [7 MC and 4 DC]) was constructed ...
Stelnicki E J - - 1997
The etiopathogenesis behind the formation of atypical craniofacial facial clefts remains unknown. To test the hypothesis that physical restricting forces such as amniotic bands can lead to the formation of these unusual clefts in the postorganogenesis period, we have modified a previously reported fetal lamb model of amniotic band syndrome ...
Carlson S R - - 1997
This study investigated twin similarity in general startle reflex reactivity and emotional modulation. Seventeen monozygotic (MZ) and 12 dizygotic (DZ) male twin pairs received startling acoustic stimuli while viewing emotionally positive, negative and neutral slides. Electromyographic (EMG) responses were recorded from the orbicularis oculi. Members of MZ twin pairs had ...
Verbeke K A - - 1997
This study presents the development of a kit formulation for the preparation of 99mTc-DMP-HSA, followed by a comparison of such kit-prepared 99mTc-DMP-HSA to 99mTc-RBCs in a volunteer. Reconstitution of the labeling kits with up to 5.55 GBq 99mTc afforded 99mTc-DMP-HSA preparations with a > 95% radiochemical purity for up to ...
Stefan M D - - 1997
Schizophrenia is the most severe of the mental illnesses and affects approximately 0.8% of the population in Western societies. Postmortem and neuroimaging studies show that patients with schizophrenia have slightly larger cerebral ventricles than normal and a decrease in cortical volume, most markedly in the left temporal lobe. These changes ...
O'Dwyer J M - - 1997
The literature suggests that mental illness is more common in people with intellectual disability than in the general population. Having reviewed the literature, Turner (1989) [Psychological Medicine 19, 301-14] suggested that about 3% of people with intellectual disability also have schizophrenia. As pregnancy and birth complications (PBCs) occur more commonly ...
Tomioka S - - 1997
The excitation of hypoglossal motoneurons innervating the genioglossus and geniohyoid muscles during transient jaw closing, the so-called jaw-closing reflex, was studied in cats. The application of diffuse pressure stimulation to the posterior palatal surface produced the jaw-closing reflex, and it was found that mechanosensory inputs from the posterior palatal mucosa ...
Tong S - - 1997
BACKGROUND: Monozygotic (Mz, identical) twinning occurs at a rate of around three per 1000 maternities in all populations, whereas dizygotic (Dz, fraternal) twinning is highly heritable, and varies with age and race. The Dz/Mz twinning ratio reflects the frequency of twin ovulations, and can provide a useful measure of human ...
Castorina P - - 1997
We report on two sets of monozygotic (MZ) twins with Williams syndrome (WS), following the 6 pairs already reported in the literature. We have confirmed monozygosity of both pairs of twins by DNA microsatellite analysis and the clinical diagnosis by fluorescence in situ hybridization using a WS-specific probe. Analysis of ...
Gordon P C - - 1997
Three experiments were performed to examine listeners' thresholds for identifying stimuli whose spectra were modeled after the vowels/I/ and /epsilon/, with the differences between these stimuli restricted to the frequency of the first formant. The stimuli were presented in a low-pass masking noise that spectrally overlapped the first formant but ...
Murray J C - - 1997
Clinical and epidemiologic studies of defined geographic populations can serve as a means of establishing data important for genetic counseling and as a first step in identifying strategies best suited for identification of causes. Under the sponsorship of Operation Smile International, clinical, genetic, and epidemiologic studies were carried out at ...
Westheimer G - - 1997
The strength of the Poggendorff illusion has been determined by a nulling method for the classical as well as other configurations of the central inducing region. Compared to a uniform field, an inducing rectangle with very low contrast produces a marked illusion, which saturates at a Michelson contrast of about ...
Jawaheer D - - 1996
Dizygotic twins are generally believed to be no more genetically similar than sibs born from separate pregnancies. In the present study, a panel of 93 dizygotic twin pairs discordant for rheumatoid arthritis were typed for HLA-A, -B, -Cw, and -DR antigens. HLA haplotype sharing identical by descent between the twins ...
Laatikainen T - - 1996
The frequency and expression of the Carabelli trait among 36 twin pairs discordant or concordant for cleft lip and/or palate were investigated. Four of 10 monozygotic (MZ) and 24 of 26 dizygotic (DZ) pairs of twins were discordant for clefts. The frequency of the trait on the first upper molars ...
Myhrman A - - 1996
BACKGROUND: Maternal stress during pregnancy has been suggested as a risk factor for schizophrenia. We tested the hypothesis that being the child of an unwanted pregnancy would be associated with later schizophrenia. METHODS: Data were collected prospectively in the Northern Finland 1966 Birth Cohort of 11 017 individuals. In the ...
Martin R A - - 1996
This study compares philtral development in the normal fetus with philtral development in specimens lacking normal philtral landmarks. Distinct differences in the structure of the upper lip were discovered between the two groups using a histological comparison. A new mechanism for the structural basis of the philtrum is proposed on ...
Ausems M G - - 1996
Three siblings from a consanguineous marriage were found to have a cleft lip. Two of them developed a progressive retinopathy which was identified as a cone-rod dystrophy. It is suggested that this association may represent a hitherto unreported entity with an autosomal recessive pattern of inheritance, although chance co-occurrence cannot ...
Davis J O - - 1996
OBJECTIVE: This co-twin study investigated monozygotic twins who were discordant for schizophrenia for evidence of prenatal growth differences between the affected and well co-twins. METHOD: Four dermatoglyphic markers of prenatal growth were obtained by established procedures from 26 monozygotic twin pairs discordant for schizophrenia, 13 monozygotic twin pairs concordant for ...
Kim T S - - 1996
The furcation involvement of 100 molars in 25 patients suffering from moderate to advanced periodontitis was investigated. The horizontal probing attachment level (PAL-H) within the furcations was assessed 2x within 2 weeks using the pressure-calibrated (0.25 N) flexible plastic universal explorer version of the TPS probe (TPS). To determine the ...
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