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81.
HG Gooszen 《Canadian Metallurgical Quarterly》1998,142(23):1311-1315
Antireflux surgery is successful in 85-90% of eligible patients, with relief of symptoms, cure of oesophagitis and possibly prevention of progression of the dysplasia in a Barrett's oesophagus. The mortality in the latest publications is given as 0.05%. The morbidity, apart from recurrences, is not yet sufficiently known. Some 250 antireflux operations are performed annually in the Netherlands, fewer than 20% of the estimated requirement of 10 operations per 100,000 of the population per year, and also fewer than in Scandinavia. Nissen fundoplication (folding the fundus of the stomach around the entire circumference (360 degrees) of the oesophagus) is generally accepted as the standard primary operation. Nissen fundoplication during laparoscopy seems to be just as good. Results of randomized clinical trials will have to be awaited to prove this assumption. Belsey's operation (folding the fundus around 270 degrees of the circumference of the oesophagus via thoracotomy) is nowadays performed almost exclusively in recurrent reflux disease and in persistent dysphagia after a primary operation. 相似文献
82.
This research examined hand preference for a bimanual task in 45 tufted capuchin (Cebus apella) and 55 rhesus macaque (Macaca mulatta) monkeys. Investigators presented subjects with plastic tubes lined with food and noted which hand the animals used to hold the tubes and which hand the animals used to remove the food. Several significant findings emerged from this investigation. First, rhesus macaques, but not tufted capuchins, exhibited a population-level bias toward use of the right hand (although the difference in direction of hand preference between species was not significant). Second, capuchins exhibited greater hand preference strength than did macaques. Third, among capuchins, but not among macaques, hand preference strength was greater for adults than for immatures. Finally, both species used their index digit to remove food most frequently when compared with other digits. Findings of hand preference direction and strength in this study were compared with other findings noted for chimpanzees which performed a bimanual tube task in a previous study. The authors conclude that using the same procedure to compare hand preference across species represents a powerful research tool that can lead to a more complete understanding of the evolution and ontogenesis of primate handedness. 相似文献
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84.
Seymour B. Elk 《Polycyclic Aromatic Compounds》2013,33(1-2):109-121
A nomenclature technique developed earlier by the author is expanded to produce an ordering of hexagons that nearly meets the original intent of Patterson's nomenclature rules in organic chemistry for a system of polycyclic aromatic hydrocarbons formed using only benzene modules. The result desired is a simple systematic method which orients a figure formed by the fusion of regular hexagonal rings so that, first, there is a maximum number of rings on a horizontal line and, second, that as many of the remaining rings as possible are above and to the right of this horizontal reference line. In the process of trying to formulate such a system, problems that are inherent in interpreting the intent of Patterson's rules and in pragmatically implementing these rules are examined. Furthermore, a minor modification of the technique produces a canonical orientation of a long molecule which can then be used to formulate the I.U.P.A.C. name for this molecule. 相似文献
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HN Nguyen D Frank S Handt HC Rieband N Maurin HG Sieberth S Matern 《Canadian Metallurgical Quarterly》1999,94(1):232-235
Intense immunosuppressive therapy is used frequently for treatment of systemic vasculitides, collagenoses, rapidly progressive glomerulonephritis, and after organ transplantation. Numerous serious treatment-related side effects include localized or disseminated opportunistic infections, and require careful monitoring of immunosuppressed patients. Gastrointestinal infections with Mycobacterium avium complex (MAC) or other nontuberculous mycobacteria have been previously identified in HIV seropositive patients only. We now report the first case of an HIV seronegative patient who received immunosuppressive therapy for rapidly progressive glomerulonephritis. The patient presented with severe lower gastrointestinal bleeding and was diagnosed to have ulcerative colitis due to infection with MAC. The patient recovered promptly after administration of antimycobacterial therapy. MAC infection should be included in the differential diagnosis of gastrointestinal bleeding in all immunodeficient patients. The significance of repeated colonoscopy to obtain multiple biopsy specimens with histological examination for foam cells and specific staining for acid-fast organisms is emphasized. 相似文献
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WJ Ellis RL Vessella JL Noteboom PH Lange RL Wolfert HG Rittenhouse 《Canadian Metallurgical Quarterly》1997,50(4):573-579
OBJECTIVES: Treatment failure after radical prostatectomy is most commonly heralded by an increase in serum prostate-specific antigen (PSA) to detectable levels. We evaluated the clinical utility of an ultrasensitive chemiluminescent PSA assay. METHODS: We evaluated the assay in banked sera obtained from 170 men after radical prostatectomy. Controls consisted of 142 females, 29 men who had undergone cystoprostatectomy without evidence of prostate cancer, and 25 men without evidence of recurrent disease at least 5 years after prostatectomy for organ-confined disease. Lead time to diagnosis of recurrence was based on comparisons with the IMx or Tandem E assays using a cutoff of 0.1 ng/mL (100 pg/mL). RESULTS: The biologic level of detection of this assay is 8 pg/mL. Serum PSA levels were undetectable in 82.4% of females, 86.2% of the cystoprostatectomy patients, and 96% of the radical prostatectomy controls. After radical prostatectomy, PSA levels were undetectable at last check in 104 of 168 (61.9%) men. In the 24 men with prostate cancer recurrence, the enhanced sensitivity of 8 pg/mL provided a mean lead time based on conservative calculations of 12.7 to 22.5 months over conventional assays. Thirty-four of the 41 men with detectable PSA levels and no evidence of disease recurrence had PSA levels of 30 pg/mL or less. CONCLUSIONS: PSA levels are undetectable in most men who do not have recurrence of disease after radical prostatectomy. Low but detectable serum PSA levels less than or equal to 30 pg/mL can be produced by nonmalignant sources of PSA. PSA assays with enhanced sensitivity can detect recurrent prostate cancer with significant lead time over conventional assays. 相似文献
90.
AC Egberts AW Lenderink FH de Koning HG Leufkens 《Canadian Metallurgical Quarterly》1997,17(3):149-155
OBJECTIVE: Trifluoromethane and CO are produced simultaneously during the breakdown of isoflurane and desflurane by dry CO2 absorbents. Trifluoromethane interferes with anesthetic agent monitoring, and the interference can be used as a marker to indicate anesthetic breakdown with CO production. This study tests representative types of gas monitors to determine their ability to provide a clinically useful warning of CO production in circle breathing systems. METHODS: Isoflurane and desflurane were reacted with dry Baralyme at 45 degrees C. Standardized samples of breakdown products were created from mixtures of reacted and unreacted gases to simulate the partial degrees of reaction which might result during clinical episodes of anesthetic breakdown using 1% or 2% isoflurane and 6% or 12% desflurane. These mixtures were measured by the monitors tested, and the indication of the wrong agent or a mixture of agents due to the presence of trifluoromethane was recorded and related to the CO concentration in the gas mixtures. RESULTS: When presented with trifluoromethane from anesthetic breakdown, monochromatic infrared monitors displayed inappropriately large amounts of isoflurane or desflurane. Agent identifying infrared and Raman scattering monitors varied in their sensitivity to trifluoromethane. Mass spectrometers measuring enflurane at mass to charge = 69 were most sensitive to trifluoromethane. CONCLUSION: Monochromatic infrared monitors were unable to indicate anesthetic breakdown via interference by trifluoromethane, but did indicate falsely elevated anesthetic concentrations. Agent identifying infrared and Raman monitors provided warning of desflurane breakdown via the interference of trifluoromethane by displaying the wrong agent or mixed agents, but may not be sensitive enough to warn of isoflurane breakdown Some mass spectrometers provided the most sensitive warnings to anesthetic breakdown via trifluoromethane, but additional data processing by some patients monitor units reduced their overall effectiveness. 相似文献