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941.
CK Chou WY Chung HC Pan LS Lee CR Wang YC Ku TY Shann 《Canadian Metallurgical Quarterly》1997,60(3):164-167
The purpose of this study was to evaluate the prenatal characteristics of congenital nephrosis of the Finnish type (CNF). Patients presenting with elevated maternal serum and/or amniotic fluid alpha-fetoprotein levels, normal ultrasound examinations and normal fetal karyotypes were included. A retrospective cohort study was conducted using questionnaires sent to all board certified clinical geneticists. Perinatal outcome, including histologic verification of CNF, was obtained. Forty index cases met the above criteria. Ten cases ultimately did not have the diagnosis of CNF, with a median MSAFP level of 7.59 MoM (range 2.7-27.64 MoM) and a median AFAFP level of 10.99 MoM (range 1.47-128.6 MoM). In the affected cohort of index pregnancies, the initial median MSAFP level was 14.49 MoM (range 3.1-38.0 MoM); the median AFAFP level was 40.0 MoM (range 2.4-80.9). MSAFP and AFAFP levels may be lower than previously recognized in patients carrying fetuses with CNF. There is significant overlap between the affected and unaffected patients. 相似文献
942.
The last two amino acids in the nascent peptide influence translation termination in E. coli (Mottagui-Tabar et al., 1994; Bj?rnsson et al., 1996). We have compared the effects on termination in Escherichia coli, Bacillus subtilis and Salmonella typhimurium obtained by varying the -1 and -2 codons upstream of the weak UGAA stop signal. The peptide effect from the penultimate amino acid on translation termination in B. subtilis is similar to that seen in E. coli (with 66.5% RF-2 amino acid sequence similarity), whereas the influence in S. typhimurium (with 95.3% similarity to E. coli) is weaker. The effect of changing the -1 codon (P-site) is weaker in S. typhimurium as compared to those in E. coli and B. subtilis. RF-2s from E. coli and S. typhimurium have a threonine or alanine at position 246, respectively. This amino acid exchange in RF-2 can explain the difference in efficiency and toxicity during overexpression when E. coli and S. typhimurium are compared (Uno et al., 1996). However, B. subtilis RF-2 also has an alanine at that position, yet the sensitivity to the nascent peptide is similar to that in E. coli. Thus, the amino acid difference at position 246 in the RF-2 sequences cannot explain why termination in E. coli and B. subtilis is similar in peptide sensitivity while being different from that in S. typhimurium. Sequence alignments of RF-2 from the three bacteria show other regions of the molecule that could be involved in the functional interactions with the C-terminal end of the nascent peptide. 相似文献
943.
944.
CM Black D Dungan E Fram CR Bird HL Rekate SP Beals JM Raines 《Canadian Metallurgical Quarterly》1998,19(2):326-329
To increase an awareness of the developmental anatomy of the nasal cavity as it applies to the radiologic work-up of choanal atresia and frontoethmoidal cephaloceles, we report two cases that demonstrate potentially serious imaging pitfalls. Two neonates with nasopharyngeal obstruction were imaged with CT and MR. Both patients had surgically proved bilateral bony choanal atresia. In addition to choanal atresia, CT showed a radiolucent, or nonossified cribriform plate and mucoid secretions within the nasal fossa, adjacent to the cribriform plate, which approximated the attenuation of brain parenchyma. In one of the patients, a preoperative diagnosis of nasopharyngeal encephalocele resulted in surgical exploration. At surgery, however, the cartilaginous cribriform plate was found to be intact. 相似文献
945.
PA Evans MA Short RG Owen AS Jack PD Forsyth CR Shiach S Kinsey GJ Morgan 《Canadian Metallurgical Quarterly》1998,16(11):3616-3627
PURPOSE: Ninety-five percent of children with acute lymphoblastic leukemia (ALL) will achieve a remission, but approximately 25% will relapse. Identifying these patients is difficult, as patients with adverse prognostic features at presentation are rare and the majority are standard risk. Analysis of minimal residual disease (MRD) may be able to determine those at risk of relapse, but the best method by which this can be accomplished has yet to be defined. The object of this study was to determine the predictive value of residual disease detection in a group of standard-risk patients with precursor-B ALL at a fixed point in therapy (week 20) using a simple fluorescent consensus immunoglobulin H (IgH) heavy chain polymerase chain reaction (PCR). PATIENTS AND METHODS: Forty-two patients who presented with precursor-B ALL with standard-risk clinical features and treated according to either the Medical Research Council (MRC) UKALL X or XI protocols were assessed using a combination of both fluorescent consensus framework I and framework III Ig heavy-chain PCR. The results of the PCR were analyzed on an ABI 373 gene sequencer with genescan software (Applied Biosystems, Foster City, CA). Clonal rearrangements detected at presentation were looked for at week 20. RESULTS: Of 42 patients, 35 had a clonal population detectable at presentation; of these, seven had more than two clonal rearrangements; this latter group showed a similar disease-free survival (DFS) to the group as a whole. Thirty of 35 patients were analyzed before their second course of intensification therapy at week 20. At this point, nine of 30 had a detectable clonal rearrangement, eight (89%) of whom have since relapsed with a median DFS of 27.5 months. Of the rest of the group (n=21), in whom no clonal rearrangement was detectable, only six (21%) have relapsed. CONCLUSION: Fluorescent IgH PCR at week 20 provides a sensitive and specific means to predict ultimate relapse (57% and 89%, respectively) and is a simple yet promising technique for the identification of patients at risk of poor outcome. 相似文献
946.
This study was performed in 36 healthy volunteers to define the relationship between plasma concentrations of partially oxidized low density lipoprotein (poxLDL), plasma glucose and insulin responses to oral glucose, and steady-state plasma glucose (SSPG) concentrations after a 180-minute infusion of somatostatin, insulin, and glucose. The concentration of poxLDL was estimated by determining the amount of conjugated dienes formed during in vitro LDL oxidation in the presence or absence of alanine. Under these conditions, the greater the in vitro antioxidant effect of alanine, the lower the amount of poxLDL that was present in plasma. The results demonstrated that plasma poxLDL concentration was significantly correlated with plasma glucose (r=.53, P<.001) and insulin (r=.43, P<.01) responses, SSPG concentrations (r=.53, P<.001), and plasma triglyceride (r=.42, P<.01) and HDL cholesterol (r=-.50, P<.002) concentrations. Furthermore, these relationships persisted when the data were corrected for differences in age, sex, body mass index, and the ratio of waist to hip girth. Of note, there was no correlation between poxLDL and LDL cholesterol concentration. When SSPG was entered along with age, sex, body mass index, and waist-to-hip ratio in a multiple regression model, SSPG alone was a significant prediction of poxLDL (r-=.37, P<.02). The addition of plasma glucose and insulin responses and triglyceride and HDL cholesterol concentrations increased the r2 to only .47. These results show that the amount of poxLDL in plasma is significantly correlated with insulin resistance (ie, SSPG) and its metabolic consequences. 相似文献
947.
BG Bylsma S Abachi P Baringer De Bonte R D Koltick FJ Loeffler EH Low RL McIlwain DH Miller CR Ng LK Rangan EI Shibata M Derrick KK Gan P Kooijman JS Loos B Musgrave LE Price J Repond K Sugano D Blockus B Brabson J Brom C Jung H Ogren HW Paik DR Rust C Akerlof J Chapman D Errede MT Ken DI Meyer D Nitz R Thun R Tschirhart B Cork 《Canadian Metallurgical Quarterly》1987,35(7):2269-2271
948.
949.
950.