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941.
Identification of a new MAGE gene with tumor-specific expression by representational difference analysis 总被引:1,自引:0,他引:1
S Lucas C De Smet KC Arden CS Viars B Lethé C Lurquin T Boon 《Canadian Metallurgical Quarterly》1998,58(4):743-752
Early pregnancy in ruminants, such as the sheep, is characterized by relatively extensive development of the conceptus before attachment to the endometrium. Between the period of blastocyst hatching and initial attachment, the uterus responds to signals from the conceptus and adapts to provide an environment that permits the establishment of pregnancy. We used large-format two-dimensional (2D) PAGE to analyze the dynamic changes in protein composition of uterine luminal fluid (ULF) during this stage of pregnancy, and we determined the contribution of each of the extraembryonic membranes and the endometrium to these changes. The majority of the more than 40 pregnancy-associated proteins in ULF at Day 17 were secreted by the conceptus. By 2D gel map comparison and Western blotting, we identified transferrin, secreted by the yolk sac from Day 15, and cytoplasmic actin, one of the most abundant proteins produced by the trophoblast at Day 17. Apolipoprotein A1 and aldose reductase, whose abundance were markedly increased in pregnancy, were identified by peptide microsequencing. Aldose reductase, an enzyme required for the conversion of glucose to fructose, was shown to be synthesized by the trophoblast, and its detection even before the formation of the placenta suggests that the synthesis of fructose may occur much earlier than previously reported. 相似文献
942.
943.
Numerous reports on the complications of craniofacial surgery have been published in the western world. However, relatively little such information concerning Oriental populations has been documented. We therefore set out to provide a retrospective analysis of all the complications of craniofacial surgery encountered during the 10-year period of 1986 to 1995 at Seoul National University Children's Hospital, the only children's hospital in Korea. Forty-nine children underwent 57 consecutive craniofacial procedures at our institution during 1986 to 1995. A retrospective chart analysis of the frequency and types of complications was performed. Mantel-Haenszel chi-square tests were then calculated for several factors, including age at surgery, duration of surgery, intraoperative losses of hemoglobin and hematocrit, total amount of blood transfusion, and the number of complications according to year, diagnosis, and operative procedure to find any significant correlation with the incidence of complications. Mortality was 1.8%. The major complication rate was 7.0% and included cases of visual loss and persistent cerebrospinal fluid leak. Analysis revealed the presence of several trends, including an increased incidence of complications with increased patient age at surgery, duration of surgery, and intraoperative loss of hematocrit. The number of complications was also noted to increase in cases with complex craniofacial synostosis syndromes (Crouzon's, Apert's Antley-Bixler, etc.) and tumors of the orbit and cranium. Finally, complications were noted to decrease in recent years, most likely due to the increased experience of our craniofacial team. Nevertheless, statistical analysis revealed that the incidence of complications correlated significantly only with increased duration of surgery (p < 0.05). The results of our study indicate that although craniofacial surgery in the Orient carries an inherent risk for significant complications, the risk can be minimized and the rate of mortality and major complications kept to an acceptable level by a careful and experienced craniofacial team. Groups at most risk for complications are those with a long duration of surgery. 相似文献
944.
CK Conners KC Wells JD Parker G Sitarenios JM Diamond JW Powell 《Canadian Metallurgical Quarterly》1997,25(6):487-497
This paper describes four studies on self-reported problems in 2,243 adolescent males and females, 12 to 17 years of age. In Study 1, principal-axis factoring of 102 items covering 11 problem domains revealed six factors comprising 49.5% of the variance. Study 2 used confirmatory factor analysis of a 64-item reduced set on a new sample of 408 adolescents. Goodness-of-fit indicators suggested that the six-factor model had excellent fit to the data. Study 3 used data from the 2,157 adolescents used in the first two studies. Coefficient alphas ranged from .83 to .92. Median test-retest reliability for the six factors was .86. There was a consistent structure of the correlation matrix across age and gender. Study 4 was a study of criterion validity, using an additional sample of 86 children with attention-deficit hyperactivity disorder (ADHD). Sensitivity and specificity were high, with an overall diagnostic efficiency of 83%. This new self-report scale, the Conners/Wells Adolescent Self-Report of Symptoms (CASS), may provide a useful component of a multimodal assessment of adolescent psychopathology. 相似文献
945.
946.
BACKGROUND: Renal functional reserve is the normal increase in renal blood flow after a protein load, and reduced or absent renal functional reserve is an early index of renal impairment. Renal blood flow is frequently reduced during acute oedematous exacerbations of chronic obstructive pulmonary disease (COPD). It is possible that patients with severe COPD in the stable state may have a reduced or absent renal functional reserve which could be a factor in oedema formation. METHODS: Sixteen stable patients with severe COPD and five normal controls were studied. The mean (SD) arterial oxygen and carbon dioxide tensions (PaO2, PaCO2) and forced expiratory volume in one second (FEV1) of patients with COPD were 8.1 (1.04) kPa, 6.3 (0.69) kPa, and 0.74 (0.27) 1, respectively. The pulsatility index (PI), an index of renovascular resistance, was measured non-invasively by Doppler ultrasonography at baseline and at intervals after a protein load of 250 g steak. RESULTS: The PI fell after the protein load in the normal subjects from 1.04 (0.19) to 0.84 (0.17), mean difference 0.20, 95% confidence interval of difference (CI) 0.14 to 0.27, p < 0.001. In the COPD group there was no change; baseline PI = 1.04 (0.16), PI after protein load = 1.08 (0.19), mean difference = -0.04, 95% CI-0.11 to 0.04, p = NS. Six of the patients with COPD were normocapnic and 10 were hypercapnic (PaCO2 > or = 6.0 kPa). The normocapnic patients had no significant change in PI (baseline PI = 1.07 (0.15), PI after protein load = 1.01 (0.16), mean difference = 0.06, 95% CI -0.03 to 0.15) while in the hypercapnic patients the PI tended to rise (baseline PI = 1.03 (0.17), PI after protein load = 1.12 (0.21), mean difference = -0.09, 95% CI 0.18 to 0.007, p = 0.06). CONCLUSIONS: Renal haemodynamics were unchanged after a protein load in patients with severe COPD, suggesting that they had no renal functional reserve. This may be a factor in the development of oedema frequently seen in patients with severe COPD, particularly in hypercapnic patients. 相似文献
947.
OBJECTIVE: Traumatic spinal cord injury (SCI) affects 8,000 to 10,000 individuals per year in the United States. One of the most difficult tasks confronting the clinician is the discussion of neurologic recovery and prognosis with the patient and/or family. Our objective is to provide a guide for practitioners to accurately predict neurologic outcome in acute traumatic cervical SCI (tetraplegia). DATA SOURCE: Published reports obtained through MEDLINE search, texts, and studies presented at national conferences. STUDY SELECTION: Peer reviewed studies, in English language, that discussed prognosis after traumatic SCI. CONCLUSION: A comprehensive physical examination of the acute SCI patient is essential in determining the initial level and classification of the injury and is the most accurate method to predict neurologic recovery. Other diagnostic tests, including somatosensory evoked potentials, magnetic resonance imaging, and transcranial magnetic stimulation, may be helpful in further determining outcome when used in association with the clinical examination. The understanding of neurologic recovery should help predict ultimate functional capability and potential needs. 相似文献
948.
En-1, En-2 and Wnt-1 are proposed to be essential signals for the development of the optic tectum in chick embryos. Drosophila engrailed and wingless, homologs of En (En-1 and En-2) and Wnt-1, respectively, have been shown to crossregulate each other. In the present paper, it is reported that crossregulation between En-2 and Wnt-1 is preserved in the development of the chick optic tectum. When En-2 is overexpressed by the replication competent retroviral vector, Wnt-1 is expressed ectopically at the dorsal midline of the diencephalon. When Wnt-1 is introduced extrinsically either by ectopic transplantation of mesencephalon, or by implantation of Wnt-1 producing cells, En-2 is induced ectopically at the dorsal midline of the tel-diencephalic border. Thus, ectopic expression of En-2 and Wnt-1 leads to crossregulation of each other in the chick brain. As diencephalon transdifferentiates into the optic tectum by an appropriate signal, the crossregulation of En-2 and Wnt-1 in the diencephalon may mimic the relationship required for early development in the tectum. 相似文献
949.
This paper describes the performance evaluation of Segnet, a CSMA/CD-based protocol with dynamic network segmentation. Segnet is shown to be suitable for network environments where the traffic pattern is highly localized into groups of stations clustered together. Some further improvements in performance are also shown to accompany the incorporation of store-and-forward buffers in Segnet stations. This is because degradations in performance caused by the segmenting of the network are minimized by temporary storage of packets which would otherwise have to be abandoned. 相似文献
950.