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31.
Steroid hormone administration causes behavior changes in many and psychosis in a few. The clinical features suggest that genetic variants of the glucocorticoid receptor or cofactors could produce susceptible subpopulations who react adversely to hormonal cascades. To investigate this possibility, coding and splice site sequences of the glucocorticoid receptor were scanned for single nucleotide polymorphisms in genomic DNA samples from 100 schizophrenics (86 Caucasians and 14 African-Americans) and 40 Caucasians with puerperal psychosis. Five amino acid substitutions were found in the amino-terminal domain at frequencies of 0.6 to 3.8% in Caucasians: R23K, F29L, L112F, D233N, and N363S. In addition, four silent nucleotide changes were found: E22E, K293K, D677D, and N766N; a transversion in intron 4 occurred beyond the splice junction. None of these variants can be linked to these disorders at present. However, the N363S variant contributes a new potential phosphorylation site and has been associated with increased body mass and reduced bone mineral density [Huizenga et al., 1998], so it is possible that the other missense variants confer traits that currently are unrecognized. Comparisons to natural glucocorticoid receptor mutants in the familial glucocorticoid resistance syndrome and steroid resistant leukemias suggest that amino acid substitutions at highly conserved residues may cause severe functional defects and serious illness, while changes at less conserved sites produce lesser alterations and milder disease.  相似文献   
32.
BACKGROUND. Bilateral blindness unrelated to simple refractive error is twice as prevalent among blacks as among whites, although the difference narrows among the elderly. The reasons for this race- and age-related pattern are uncertain. METHODS AND RESULTS. A randomly selected, stratified, multistage cluster sample of 2395 blacks and 2913 whites 40 years of age and older in East Baltimore underwent detailed ophthalmic examinations by a single team. We identified 64 subjects who were blind in both eyes. The leading causes of blindness were unoperated senile cataract (accounting for blindness in 27 of the total of 128 eyes), primary open-angle glaucoma (17 eyes), and age-related macular degeneration (16 eyes). Together, these three disorders accounted for 47 percent of all blindness in this sample. Unoperated cataract accounted for 27 percent of all blindness among blacks, among whom it was four times more common than among whites; whites were almost 50 percent more likely than blacks to have undergone cataract extraction before the age of 80 (P less than 0.002). Primary open-angle glaucoma accounted for 19 percent of all blindness among blacks; it was six times as frequent among blacks as among whites and began 10 years earlier, on average. By contrast, age-related macular degeneration resulting in blindness was limited to whites, among whom it was the leading cause of blindness (prevalence, 2.7 per 1000; 95 percent confidence interval, 1.2 to 5.4); it affected 3 percent of all white subjects 80 years of age or older. CONCLUSIONS. The pattern of blindness in urban Baltimore appears to be different among blacks and whites. Whites are far more likely to have age-related macular degeneration, and blacks to have primary open-angle glaucoma. The high rate of unoperated cataracts among younger blacks and among elderly subjects of both races suggests that health services are underused. Half of all blindness in this urban population is probably preventable or reversible.  相似文献   
33.
Similar patterns of germline mutations in the factor IX gene (F9) have been observed in certain geographically and racially diverse populations. Germline mutation data have not been available from any region of Africa or from the Black race. Analysis of mutation data for Blacks is of interest, since this race has a high frequency of polymorphism compared to other races. This high frequency has been interpreted as evidence for the "out of Africa" hypothesis for the origin of humans, but it is possible that Blacks have a higher mutation rate due to genetic differences or environmental exposures. We report 26 independent mutations that were detected in patients of mixed races with hemophilia B from South Africa. The pattern of mutation in patients from this African country was similar to that of U.S. Caucasians. In addition, 22 independent mutation were detected in African American patients. The patterns of independent germline mutation in 22 African Americans (and in a combination 34 North American and African Blacks) is similar to that of U.S. Caucasians. Neither genetic differences between the Black and Caucasian races nor environmental and cultural differences between South Africa and the U.S. alter the germline pattern of mutation observed in F9. Hum Mutat 16:372, 2000.  相似文献   
34.
The activation of the tris(allyl)neodymium complex Nd(η3-C3H5)3 · dioxane with alkylaluminoxanes (MAO or HIBAO) results in highly selective catalysts for the 1,4-cis-polymerization of butadiene (cis-selectivity up to 80%). Under standard conditions (50°C, toluene), the turnover frequency (TOF) of the catalyst/MAO system amounts to 10–15000 mol butadiene/(mol Nd · h). Molecular weight determinations indicate the formation of only one polymer chain per neodymium center as in a living polymerization reaction, and for the catalyst/HIBAO system the rate law rp = kp [Nd][C4H6] with kp = 8,7 · 10?2 mol/(L · s) (at 25°C) has been derived. As the catalytically active species, a cationic monobutenyl neodymium(III) complex is discussed, which is stabilized through coordinative interaction with the counter anion as well as the growing polybutadiene chain. This cationic complex reacts under insertion with butadiene in a bimolecular fashion.  相似文献   
35.
Zusammenfassung Über einen Zeitraum von 8 bis 12 Monaten wurden 1 Patient mit primärer und 2 Patienten mit sekundärer Osteoporose bei Osteogenesis imperfecta mit hochgereinigtem Wachstumshormon aus menschlichen Hypophysen behandelt. Aus den Ergebnissen der laborchemischen, knochenhistologischen und kinetischen Untersuchungen mit47Calcium vor und nach der Therapie ließ sich kein positiver Effekt auf die Knochenerkrankung ermitteln. Dies steht im Gegensatz zu tierexperimentellen Untersuchungen an ausgewachsenen Hunden, bei denen es bereits 3 Monate nach Beginn der Applikation von Wachstumshormon zu einer Positivierung der Knochenbilanz gekommen war.  相似文献   
36.
37.
Estrogen and thyroid hormones exert effects on growth, development, and differentiation of the nervous system. Hormone administration can lead to changes in behavior, suggesting that genetic variants of the estrogen receptor alpha (ERalpha) and the thyroid hormone receptor alpha (TRalpha) genes may predispose to psychiatric diseases. To investigate this possibility, regions of likely functional significance (all coding exons and flanking splice junctions) of the ERalpha and TRalpha genes were scanned in patients with schizophrenia (113), along with pilot studies in patients with bipolar illness (BPI), puerperal psychosis, autism, attention-deficit hyperactivity disorder (ADHD), and alcoholism. A total of 1.18 megabases of the ERalpha gene and 1.16 megabases of the TRalpha gene were scanned with Detection of Virtually All Mutations-SSCP (DOVAM-S), a method that detects virtually all mutations. Four missense mutations, seven silent mutations and one deletion were identified in the ERalpha gene, while only four silent mutations were present in the TRalpha gene. Two of the missense mutations in ERalpha are conserved in the six available mammalian and bird species (H6Y, K299R) and a third sequence variant (P146Q) is conserved in mammals, birds, and Xenopus laevis, hinting that these sequence changes will be of functional significance. These changes were found in one patient each with BPI, puerperal psychosis, and alcoholism, respectively. Analysis of the ERalpha and TRalpha genes in 240 subjects reveals that missense changes and splice site variants are uncommon (1.7% and 0%, respectively). Further analyses are necessary to determine if the missense mutations identified in this study are associated with predisposition or outcome for either psychiatric or nonpsychiatric diseases.  相似文献   
38.
Summary Neurological complications are a major cause of morbidity and mortality in patients with disseminated malignant melanoma. We have studied and correlated clinical and cerebrospinal fluid (CSF) findings in 20 patients with central nervous system metastases from malignant melanoma including 8 patients with metastatic meningeal melanomatosis (MMM) and 12 patients with solid cerebral metastases (SCM). The putative CSF tumor markers, fibronectin and 2-microglobulin, were elevated significantly in MMM but not in SCM patients. A prominent increase in the IgM index, which reflects intrathecal B-cell stimulation, and a rise of IgG index, interleukin-6, and tumor necrosis factor- in MMM patients provide preliminary evidence for a local intrathecal immune response triggered by melanoma cell invasion of the subarachnoid space.  相似文献   
39.
This study reports our experience with low-dose prostaglandin E1 (PGE1) treatment of 91 newborns with ductus dependent congenital heart disease (CHD). PGE1 efficacy, side-effects as well as the cardiovascular and respiratory profile of the patients were analysed. PGE1 doses > 0.02 g/kg per minute were used for only 5.3% of the total 23 656 h of treatment. The mean systolic blood pressures did not differ from the normal mean for patients with cyanotic CHD, while the diastolic values were lowered. Respiratory support was required only during 13.7% of the total treatment time. Apnoeas occurred in 21 (38%) of the 55 spontaneously breathing infants, who all had a cyanotic CHD. The incidence of apnoeas was lower during treatment with doses < 0.01 g/kg per minute.  相似文献   
40.

Curent Activities of Japanese Society for Oral and Maxillofacial Radiolory, 1994

Abstracts—dental radiology vol.34, 1994  相似文献   
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