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991.
992.
JM LaBerge EJ Ring RL Gordon JR Lake MM Doherty KA Somberg JP Roberts NL Ascher 《Canadian Metallurgical Quarterly》1993,187(2):413-420
One hundred patients underwent transjugular intrahepatic portosystemic shunt (TIPS) creation for variceal bleeding (n = 94), intractable ascites (n = 3), hepatorenal syndrome (n = 2), and preoperative portal decompression (n = 1). Shunts were completed in 96 patients. Portal vein pressure was reduced from 34.5 mm Hg +/- 7.6 (standard deviation) to 24.5 mm Hg +/- 6.2; the residual portal vein-hepatic vein gradient was 10.4 mm Hg +/- 0.9. Acute variceal bleeding was controlled in 29 of 30 patients. Of the 96 patients who underwent successful TIPS creation, 26 have died and 22 have undergone liver transplantation; the remaining 48 patients have survived an average of 7.6 months. Variceal bleeding recurred in 10 patients. Fifteen patients developed shunt stenosis (n = 6) or occlusion (n = 9). Patency was reestablished in eight of the nine occluded shunts. Seventeen patients developed new or worsened encephalopathy. The authors conclude that TIPS creation is an effective and reliable means of lowering portal pressure and controlling variceal bleeding, particularly in patients with acute variceal bleeding unresponsive to sclerotherapy and patients with chronic variceal bleeding before liver transplantation. 相似文献
993.
994.
995.
WG Negendank R Sauter TR Brown JL Evelhoch A Falini ED Gotsis A Heerschap K Kamada BC Lee MM Mengeot E Moser KA Padavic-Shaller JA Sanders TA Spraggins AE Stillman B Terwey TJ Vogl K Wicklow RA Zimmerman 《Canadian Metallurgical Quarterly》1996,84(3):449-458
Budding yeast (Saccharomyces cerevisiae) Rap1p has been expressed in fission yeast (Schizosaccharomyces pombe) under the control of the regulatable fructose bisphosphatase (fbp) promoter. When the fbp promoter was derepressed, cells containing the complete RAP1 gene failed to show any significant growth, suggesting that Rap1p is toxic. A derivative of Rap1p that has a temperature-sensitive mutation in the DNA-binding domain was not toxic in cells grown at 37 degrees C, a temperature at which DNA binding by rap1p(ts) is severely inhibited. Removal of a short region downstream of the DNA-binding domain, including a region previously shown to be essential for Rap1p toxicity in budding yeast, also abolished the toxic effect. The toxic effect of Rap1p has therefore been conserved between two distantly related yeasts. In budding yeast, overexpression of Rap1p also caused changes to the lengths of the telomeric repeats. No effects on telomeres were detected in fission yeast. 相似文献
996.
Chondrocytes in cartilage are embedded in a matrix containing a high concentration of proteoglycans and hence of fixed negative charges. Their extracellular ionic environment is thus different from that of most cells, with extracellular Na+ being 250-350 mM and extracellular osmolality 350-450 mOsm. When chondrocytes are isolated from the matrix and incubated in standard culture medium (DMEM; osmolality 250-280 mOsm), their extracellular environment changes sharply. We incubated isolated bovine articular chondrocytes and cartilage slices in DMEM whose osmolality was altered over the range 250-450 mOsm by Na+ or sucrose addition. 35S-sulphate and 3H-proline incorporation rates were at a maximum when the extracellular osmolality was 350-400 mOsm for both freshly isolated chondrocytes and for chondrocytes in cartilage. The incorporation rate per cell of isolated chondrocytes was only 10% that of chondrocytes in situ both 4 and 24 hours after isolation. For freshly isolated chondrocytes, the rate increased 30-50% in DMEM to which NaCl or sucrose had been added to increase osmolality. In chondrocytes incubated overnight in DMEM, the rate was greatest in DMEM of normal osmolality and fell from the maximum in proportion to the change in osmolality. The effects of sucrose addition on incorporation rates were similar but not identical to those of Na+ addition. Changes in cell volume might be linked to changes in synthesis rates since the cell volume of chondrocytes (measured by Coulter-counter) increased 30-40% when the cells were removed from their in situ environment into DMEM. Synthesis rates can thus be partly regulated by changes in extracellular osmolality, which in cartilage is controlled by proteoglycan concentration. This provides a mechanism by which the chondrocytes can rapidly respond to changes in extracellular matrix composition. 相似文献
997.
998.
MJ Fuhrer DH Rintala KA Hart R Clearman ME Young 《Canadian Metallurgical Quarterly》1993,74(3):255-260
Depressive symptomatology was studied in a community-based sample of 100 men and 40 women with spinal cord injury. The mean for the Center for Epidemiologic Studies Depression Scale was higher than that reported previously for the general population, and the mean for women was higher than that for men. Findings from the Mobility dimension of the Craig Handicap Assessment and Reporting Technique (CHART) suggested that differences between men and women in degree of mobility within home and community partly mediate the gender difference in depressive symptomatology. Other CHART dimensions, Social Integration and Occupation, were inversely related with depression scores, although these dimensions did not differentiate men and women. A statistically significant relationship was not obtained between depression and disability, assessed by a self-report version of the Functional Independence Measure, or between depression and impairment, reflected by the ASIA Total Motor Index Score. Depression was not related with the presence of either pressure ulcers or presumptive evidence of urinary tract infection. 相似文献
999.
A new method has been developed to raise antibodies against synthetic peptides. A multiple antigenic peptide system (MAP) containing a branched oligolysine was synthesized on a beaded polystyrene polyoxyethylene graft copolymer resin, which acts as a synthetic hapten carrier for use in immunization. The peptides, already attached to the carrier, can be used directly after final deprotection without any further purification steps. The utility of this peptide-carrier conjugate is highlighted by its additional application for affinity purification of antibodies generated. 相似文献
1000.
KA Johnson MF Kijewski JA Becker B Garada A Satlin BL Holman 《Canadian Metallurgical Quarterly》1993,34(11):2044-2048
To improve the diagnostic utility of brain single-photon emission computed tomography (SPECT) in Alzheimer's disease (AD), we have developed and evaluated an objective method of differentiating patients and healthy elderly controls using a quantitative image analysis protocol. HMPAO-SPECT image datasets from 29 patients with probable AD and 78 age-matched controls were registered to a common anatomic frame of reference. Activity levels within 120 standardized cortical volumes were determined by an automated procedure. Subjects were classified into normal and AD groups by quadratic discriminant analysis using two features: global average activity level and average normalized activity levels within the two clusters of standardized volumes identified as most significantly different in AD by analysis of covariance. The classification used split-half replication to ensure valid results. Classification performance quantified by the area under a binormal ROC curve fitted to the data was 0.923 +/- 0.036; at a threshold likelihood ratio of 1, the sample sensitivity was 91% and specificity was 86%. We conclude that quantitative SPECT accurately distinguishes AD patients from elderly controls. 相似文献