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991.
KH Fuchs J Heimbucher SM Freys M Fein A Thiede 《Canadian Metallurgical Quarterly》1998,123(10):1152-1156
This is a report on a questionnaire in Germany reflecting the activity in antireflux surgery, both in open and laparoscopic modifications in the time period of 1990 through 1995. It serves as an overview of the acceptance of diagnostic workup, indication, applied techniques, and different antireflux procedures. In a total of 104 representative hospitals, 2,036 patients were operated during this time. Almost 80% of the hospitals provide antireflux surgery in the open technique and only 1/3 of the hospitals have experience in the laparoscopic technique. There is a total rise in antireflux surgery during the last 5 years, since the number of laparoscopic antireflux operations rises constantly with a total amount of open operations of about 250 cases per year. In open surgery the most favourite technique is the Nissen-Rossetti procedure, while in laparoscopic technique the choice for the original Nissen, the Nissen-Rossetti, or the floppy Nissen technique is divided in almost equal parts. 相似文献
992.
993.
RD Flannagan SP Tammariello KH Joplin RA Cikra-Ireland GD Yocum DL Denlinger 《Canadian Metallurgical Quarterly》1998,95(10):5616-5620
Several cDNAs isolated from brains of diapausing pupae of the flesh fly, Sarcophaga crassipalpis, show expression patterns unique to diapause. To isolate such cDNAs a diapause pupal brain cDNA library was screened by using an elimination hybridization technique, and cDNAs that did not hybridize with cDNA probes constructed from the RNA of nondiapausing pupae were selected for further screening. The 95 clones that did not hybridize in the initial library screen were selected for further characterization. These clones were then screened against diapause and nondiapause pupal poly(A)+ Northern blots. The secondary screen identified 4 diapause-up-regulated clones, 7 diapause-down-regulated clones, 8 clones expressed equally in both diapause and nondiapause, and 75 clones without detectable expression. The diapause-up-regulated and down-regulated clones were further characterized by partial DNA sequencing and identity searches by using GenBank. Identities between our cloned cDNAs and other genes included those linked to cell cycle progression, stress responses, and DNA repair processes. The results suggest that insect diapause is not merely a shutdown of gene expression but is a unique, developmental pathway characterized by the expression of a novel set of genes. 相似文献
994.
Insulin-dependent diabetes mellitus (IDDM) and Graves' disease (GD) are autoimmune endocrinopathies and associated with distinct HLA-DR and -DQ alleles as well as several tumor necrosis factor alpha (TNF-alpha) and beta (TNF-beta) alleles. TNF-alpha and TNF-beta interact with TNF receptor (TNF-R), of which two subtypes have been described: TNF-R1 and TNF-R2. We investigated TNF-R2 alleles in 90 patients with IDDM, 101 with GD and 70 healthy controls. Genomic DNA was amplified with specific flanking primers for the untranslated 3' region of TNF-R2. SSCP analysis revealed two alleles by different fragment patterns: TNF-R2*1 and TNF-R2*2. Patients with IDDM or Graves' disease and controls did not differ significantly: TNF-R2*1/*1:IDDM(8%)/GD(2%)/KO(4%); TNF-R2*2/*2:IDDM(34%)/GD(48%)/KO(42%), heterozygosity TNF-R2*1/*2:IDDM(58%)/GD(50%)/KO(54%) (IDDM vs KO: P=0.46, chi2=1.57; GD vs KO: P=0.59, chi2=1.05). In conclusion, the studied polymorphism of TNF-R2 was associated with neither IDDM nor GD in a German population. 相似文献
995.
996.
KH Herzog MJ Chong M Kapsetaki JI Morgan PJ McKinnon 《Canadian Metallurgical Quarterly》1998,280(5366):1089-1091
Ataxia telangiectasia (AT) is characterized by progressive neurodegeneration that results from mutation of the ATM gene. However, neither the normal function of ATM in the nervous system nor the biological basis of the degeneration in AT is known. Resistance to apoptosis in the developing central nervous system (CNS) of Atm-/- mice was observed after ionizing radiation. This lack of death occurred in diverse regions of the CNS, including the cerebellum, which is markedly affected in AT. In wild-type, but not Atm-/- mice, up-regulation of p53 coincided with cell death, suggesting that Atm-dependent apoptosis in the CNS is mediated by p53. Further, p53 null mice showed a similar lack of radiation-induced cell death in the developing nervous system. Atm may function at a developmental survival checkpoint that serves to eliminate neurons with excessive DNA damage. 相似文献
997.
We have examined maternal urine concentrations of beta core, free beta human chorionic gonadotrophin (hCG), and total oestriol in 373 control pregnancies and 43 pregnancies affected by aneuploidy (including 22 cases of Down's syndrome) in an attempt to see if any of the analytes have a value in Down's syndrome screening between the tenth and 14th week of pregnancy. We have compared the performance of these analytes against nuchal translucency measurement combined with maternal serum free beta hCG at the same period of pregnancy. Our results show that levels of urine free beta hCG and beta core are increased in Down's syndrome with average multiple of the median levels of 1.81 and 2.91, respectively. Urine total oestriol was reduced (0.83) whilst maternal serum free beta hCG was increased (1.72). In trisomy 18 the levels of all analytes were reduced, although serum free beta hCG was the most discriminating. The spread of results in the control and the Down's group for urine beta core was more than three times than that for serum free beta hCG and with urine free beta hCG it was two times wider. In combination with maternal age, urine total oestriol had a 32 per cent detection rate at a fixed 5 per cent false-positive rate; urine beta core 34 per cent, urine free beta hCG 36 per cent, maternal serum free beta hCG 44 per cent, and nuchal translucency 82 per cent. In combination with nuchal translucency, urine total oestriol added an extra 1 per cent detection, urine beta core an extra 2 per cent, urine free beta hCG an extra 3 per cent, and serum free beta hCG an extra 5 per cent. It is unlikely that any of the urine markers will be of value in first-trimester screening. Optimal first-trimester screening programmes will rely for the foreseeable future on nuchal translucency, serum free beta hCG, and possibly pregnancy-associated plasma protein A. 相似文献
998.
UK von Schwedler TL Stemmler VY Klishko S Li KH Albertine DR Davis WI Sundquist 《Canadian Metallurgical Quarterly》1998,17(6):1555-1568
After budding, the human immunodeficiency virus (HIV) must 'mature' into an infectious viral particle. Viral maturation requires proteolytic processing of the Gag polyprotein at the matrix-capsid junction, which liberates the capsid (CA) domain to condense from the spherical protein coat of the immature virus into the conical core of the mature virus. We propose that upon proteolysis, the amino-terminal end of the capsid refolds into a beta-hairpin/helix structure that is stabilized by formation of a salt bridge between the processed amino-terminus (Pro1) and a highly conserved aspartate residue (Asp51). The refolded amino-terminus then creates a new CA-CA interface that is essential for assembling the condensed conical core. Consistent with this model, we found that recombinant capsid proteins with as few as four matrix residues fused to their amino-termini formed spheres in vitro, but that removing these residues refolded the capsid amino-terminus and redirected protein assembly from spheres to cylinders. Moreover, point mutations throughout the putative CA-CA interface blocked capsid assembly in vitro, core assembly in vivo and viral infectivity. Disruption of the conserved amino-terminal capsid salt bridge also abolished the infectivity of Moloney murine leukemia viral particles, suggesting that lenti- and oncoviruses mature via analogous pathways. 相似文献
999.
A Heinemann M Sterneck R Kuhlencordt X Rogiers KH Schulz B Queen F Wischhusen K Püschel 《Canadian Metallurgical Quarterly》1998,22(8):1806-1812
We tested the diagnostic validity of carbohydrate-deficient transferrin (CDT) as an indicator for relapse into elevated alcohol consumption among patients who were examined under follow-up treatment before (n = 147) and after (n = 102) orthotopic liver transplantation (OLT) in the outpatient-department of the University Hospital Department of Surgery in Hamburg-Eppendorf. CDT measurements were performed with two commercial kits in parallel (CDTect-RIA and CDT%-RIA). Short-term parameters of alcohol consumption (ethanol, methanol) indicated relapses into elevated alcohol consumption in 11.4% of the evaluated patients with alcoholic liver disease (ALD) before transplantation. Before OLT, median CDT values were determined to be elevated among patients with alcoholic as well as nonalcoholic end-stage liver diseases (NALD). Among patients with ALD, we found elevated CDT medians even in those who were successfully scheduled for OLT after long-term evidence of abstinence proved by biochemical short-term parameters and psychological tests. Both CDTect and CDT% assays had comparable low specificities in selected patient groups before transplantation. CDT% and CDTect were negatively correlated with the albumin level. Before the study ended, CDT was no longer implemented in the evaluation of whether an OLT should be administered. This was due to inconsistent results of CDT in ALD as well as NALD. After OLT, patients with ALD, as well as NALD, had statistically significant lower CDT medians than before OLT, which ranged within reference levels. We determined, according to CDT, elevated alcohol consumption subsequent to OLT in 4 of 13 patients with ALD who underwent transplantation during the study (median observation period: 10 months). CDT does not appear to be useful in evaluating patients before OLT. With regained specificity and high sensitivity in patients after OLT, CDT could be recommended as a standard instrument for quality control in patients with ALD after liver transplantation. 相似文献
1000.
MC Lee JH Nam C Choi CS Park SW Juhng KH Yang BS Yang CH Suh SU Kim 《Canadian Metallurgical Quarterly》1997,21(4):393-404
The study was performed to determine the ultrastructural characteristics of central neurocytoma and its features in primary cell culture. Fresh tissue from three tumors was mechanically and enzymatically dissociated into individual cells, which were cultured onto poly-L-lysine precoated Aclar coverslips in the media. The tumor cells attached to the surface of the coverslips within 12 to 24 h and delicate cytoplasmic processes developed within 2 to 3 days. Electron microscopic examination of the cultured tumor cells and the tumor tissue supported neuronal origin. Combined tissue culture and electron microscopic study provides a rapid, reliable, and reproducible means for the diagnosis of central neurocytoma. 相似文献