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811.
812.
In a 51-year-old woman with bilateral Brenner tumours of the ovaries and with intermittent hydrothorax and ascites, Meigs' syndrome was diagnosed. The serum CA 125 level was 620 U/ml (normal: 5-35). Bilateral ovariectomy, hysterectomy and omentectomy were carried out. The ovaries were not enlarged. Postoperatively, the pleural effusion and ascites resolved and the CA 125 level decreased to 8.4 U/ml. The pathogenesis of hydrothorax probably involves passage through the diaphragm, and the CA 125 may be produced by the peritoneal lining or by the Brenner tumours. 相似文献
813.
814.
Observers watched for 1 or 2 colored words as targets presented in lists of distractor strings (10 items/s). Identification of 1 target (T1) temporarily reduced the accuracy of reporting a 2nd target (T2). This attentional blink (AB) effect was most pronounced when T1 and T2 occurred close together in time. Use of recognition tests (instead of recall) improved performance but did not eliminate the AB effect. The AB effect was found with both word and nonword distractors, a smaller AB effect was found with consonant string distractors, and the AB effect was substantially attenuated with strings of unfamiliar characters (a false font). Analyses of errors indicated that the 2nd target is frequently replaced or corrupted by the following distractor during the blink. The AB effect appears to result from both attentional and mnemonic processes. 相似文献
815.
816.
AC Heath KK Bucholz PA Madden SH Dinwiddie WS Slutske LJ Bierut DJ Statham MP Dunne JB Whitfield NG Martin 《Canadian Metallurgical Quarterly》1997,27(6):1381-1396
BACKGROUND: Genetic influences on alcoholism risk are well-documented in men, but uncertain in women. We tested for gender differences in genetic influences on, and risk-factors for, DSM-III-R alcohol dependence (AD). METHOD: Diagnostic follow-up interviews were conducted in 1992-3 by telephone with twins from an Australian twin panel first surveyed in 1980-82 (N = 5889 respondents). Data were analysed using logistic regression models. RESULTS: Significantly higher twin pair concordances were observed in MZ compared to DZ same-sex twin pairs in women and men, even when data were weighted to adjust for over-representation of well-educated respondents, and for selective attrition. AD risk was increased in younger birth cohorts, in Catholic males or women reporting no religious affiliation, in those reporting a history of conduct disorder or major depression and in those with high Neuroticism, Social Non-conformity, Toughmindedness, Novelty-Seeking or (in women only) Extraversion scores; and decreased in 'Other Protestants', weekly church attenders, and university-educated males. Controlling for these variables, however, did not remove the significant association with having an alcoholic MZ co-twin, implying that much of the genetic influence on AD risk remained unexplained. No significant gender difference in the genetic variance in AD was found (64% heritability, 95% confidence interval 32-73%). CONCLUSIONS: Genetic risk-factors play as important a role in determining AD risk in women as in men. With the exception of certain sociocultural variables such as religious affiliation, the same personality, sociodemographic and axis I correlates of alcoholism risk are observed in women and men. 相似文献
817.
AF Schier SC Neuhauss KA Helde WS Talbot W Driever 《Canadian Metallurgical Quarterly》1997,124(2):327-342
The zebrafish locus one-eyed pinhead (oep) is essential for the formation of anterior axial mesoderm, endoderm and ventral neuroectoderm. At the beginning of gastrulation anterior axial mesoderm cells form the prechordal plate and express goosecoid (gsc) in wild-type embryos. In oep mutants the prechordal plate does not form and gsc expression is not maintained. Exposure to lithium, a dorsalizing agent, leads to the ectopic induction and maintenance of gsc expression in wild-type embryos. Lithium treatment of oep mutants still leads to ectopic gsc induction but not maintenance, suggesting that oep acts downstream of inducers of dorsal mesoderm. In genetic mosaics, wild-type cells are capable of forming anterior axial mesoderm in oep embryos, suggesting that oep is required in prospective anterior axial mesoderm cells before gastrulation. The oep gene is also essential for endoderm formation and the early development of ventral neuroectoderm, including the floor plate. The loss of endoderm is already manifest during gastrulation by the absence of axial-expressing cells in the hypoblast of oep mutants. These findings suggest that oep is also required in lateral and ventral regions of the gastrula margin. The sonic hedgehog (shh).gene is expressed in the notochord of oep animals. Therefore, the impaired floor plate development in oep mutants is not caused by the absence of the floor plate inducer shh. This suggests that oep is required downstream or in parallel to shh signaling. The ventral region of the forebrain is also absent in oep mutants, leading to severe cyclopia. In contrast, anterior-posterior brain patterning appears largely unaffected, suggesting that underlying prechordal plate is not required for anterior-posterior pattern formation but might be involved in dorsoventral brain patterning. To test if oep has a wider, partially redundant role, we constructed double mutants with two other zebrafish loci essential for patterning during gastrulation. Double mutants with floating head, the zebrafish Xnot homologue, display enhanced floor plate and adaxial muscle phenotypes. Double mutants with no tail (ntl), the zebrafish homologue of the mouse Brachyury locus, display severe defects in midline and mesoderm formation including absence of most of the somitic mesoderm. These results reveal a redundant function of oep and ntl in mesoderm formation. Our data suggest that both oep and ntl act in the blastoderm margin to specify mesendodermal cell fates. 相似文献
818.
Cytosolic glutathione S-transferase is a family of multi-functional enzymes involved in the detoxification of a large variety of xenobiotic and endobiotic compounds through glutathione conjugation. The three-dimensional structure of Escherichia coli glutathione S-transferase complexed with glutathione sulfonate, N-(N-L-gamma-glutamyl-3-sulfo-L-alanyl)-glycine, has been determined by the multiple isomorphous replacement method and refined to a crystallographic R factor of 0.183 at 2.1 A resolution. The E. coli enzyme is a globular homodimer with dimensions of 58 Ax56 Ax52 A. Each subunit, consisting of a polypeptide of 201 amino acid residues, is divided into a smaller N-terminal domain (residues 1 to 80) and a larger C-terminal one (residues 89 to 201). The core of the N-terminal domain is constructed by a four-stranded beta-sheet and two alpha-helices, and that of the C-terminal one is constructed by a right-handed bundle of four alpha-helices. Glutathione sulfonate, a competitive inhibitor against glutathione, is bound in a cleft between the N and C-terminal domains. Therefore, the E. coli enzyme conserves overall constructions common to the eukaryotic enzymes, in its polypeptide fold, dimeric assembly, and glutathione-binding site. In the case of the eukaryotic enzymes, tyrosine and serine residues near the N terminus are located in the proximity of the sulfur atom of the bound glutathione, and are proposed to be catalytically essential. In the E. coli enzyme, Tyr5 and Ser11 corresponding to these residues are not involved in the interaction with the inhibitor, although they are located in the vicinity of catalytic site. Instead, Cys10 N and His106 Nepsilon2 atoms are hydrogen-bonded to the sulfonate group of the inhibitor. On the basis of this structural study, Cys10 and His106 are ascribed to the catalytic residues that are distinctive from the family of the eukaryotic enzymes. We propose that glutathione S-transferases have diverged from a common origin and acquired different catalytic apparatuses in the process of evolution. 相似文献
819.
The study objective was to assess the value of outpatient follow-up of patients who undergo routine uncomplicated nasal surgery. A total of 177 postoperative patients (117 males, 60 females) undergoing routine nasal surgery at the Raigmore Hospital, Inverness, was selected over a six-month period, 92 of whom (60 males, 32 females) were requested to return to the clinic for a follow-up session. A total of 72 (78.3%) patients attended for post-operative review. Of these, 55 patients (76.4%) had achieved a satisfactory result from surgery and 17 (23.6%) required additional treatment for persistent problems. The former group were pleased with the outcome of their operation and required no further treatment. Of the 25 patients who were prescribed medication at the time of discharge from hospital, 19 (76.0%) were still complying with the medication and required no further specialist assistance. The results suggest that routine follow-up of uncomplicated cases of nasal surgery is unnecessary. The good therapeutic results in the majority of cases indicate a need to decrease the number of routine reviews to reduce the high non-attendance rate and increase the proportion of new patients seen at outpatient clinics. The role played by general practitioners is vital to this cause. This would include minor postoperative care, monitoring of prescribed medication and review of patients with occasional postoperative problems. 相似文献
820.
SL Schwartz C Hanson C Lucas S Rosenblatt J Rosenstock F Whittier D Wistran C Riche WS Mulcahy 《Canadian Metallurgical Quarterly》1993,15(1):79-87
The capacity of a human monoclonal antibody (MAb 33G2) to interfere in vitro both with Plasmodium falciparum merozoite invasion and cytoadherence of infected erythrocytes to melanoma cells has been reported. MAb 33G2 cross-reacts with several P. falciparum antigens but shows highest reactivity with repeated sequences in the asexual blood stage antigen Pf332. This study was conducted in order to further analyze the cytoadherence inhibition mediated by MAb 33G2 and to evaluate the relative contribution of antibodies to Pf332 in the inhibitory activity of immunoglobulins from P. falciparum immune donors. We show here that MAb 33G2 inhibits cytoadherence of infected erythrocytes (PRBCs) with similar efficiency independently of the strain of parasite, while the inhibitory capacity of immunoglobulin fractions from Liberian immune donors was restricted to some strains only. There appears to be no correlation between the reactivity with Pf332 of immunoglobulin preparations from different donors and their capacity to inhibit cytoadherence of PRBCs to melanoma cells. In contrast to MAb 33G2, polyclonal antibodies affinity purified on the Pf332 peptide containing the epitope seen by the MAb showed little or no inhibition of cytoadherence of infected erythrocytes. 相似文献