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21.
Retinoblastoma and the progression of tumor genetics   总被引:10,自引:0,他引:10  
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22.
Basement membranes were separated from rat glomeruli and purified by mild procedures, which led to a highly enriched basement membrane fraction. Here, the production and characterization of five monoclonal antibodies against tubular and glomerular basement membranes are described. These antibodies were analyzed immunohistochemically on frozen sections of rat, bovine, and human kidneys as well as on rat embryos. One monoclonal antibody (BM O II) exclusively recognized the glomerular basement membranes, another one (BM O VII) bound to tubular basement membranes and to Bowman's capsule. Three antibodies (BM O IV, BM M II, BM M III) recognized their antigens in both glomerular and tubular basement membranes as well as in mesangial cells. The BM O II antibody showed a stringent species specificity and bound only to glomerular basement membranes of the rat. The other four antibodies cross-reacted with human and bovine glomerular basement membrane and mesangial antigens; they also bound to other tissues in the developing rat embryo. Antibody binding to specific purified components of the basement membranes such as collagen type IV, laminin, heparan sulphate proteoglycan, and fibronectin was investigated by enzyme-linked immunosorbent assay (ELISA). None of these antibodies reacted with any of these known basement membrane components, indicating that the antibodies may serve as useful tools in future investigations of so far unidentified components of basement membranes.  相似文献   
23.
Abstract Pseudomonas sp. strain RW611 utilized the ammonium salt of 2-sulfobenzoate as sole source of carbon, sulfur, nitrogen, and energy. The xenobiotic sulfo substituent was dioxygenolytically eliminated as sulfite, which was then slowly oxidized to sulfate. 2,3-Dihydroxybenzoate, which resulted from desulfonation underwent meta -cleavage, mediated by 2,3-dihydroxybenzoate 3,4-dioxygenase activity. This enzyme was inhibited by 3-chlorocatechol and 2,3,4-trihydroxybenzoate.  相似文献   
24.
To assess whether oxidative stress contributes to the ischemia/reperfusion injury of aortic surgery, the contents of alpha-tocopherol, alpha-tocopheryl quinone, ascorbate, lipid-derived malondialdehyde, protein thiols, cholesterol, and lactate were analyzed in plasma samples from 24 patients subjected to aortic crossclamping. alpha-Tocopherol, ascorbate, and protein thiols decreased during ischemia, whereas alpha-tocopheryl quinone increased in all but two cases, doubling on average in proportion to alpha-tocopherol. Upon reperfusion alpha-tocopherol, ascorbate, and protein thiols remained low, whereas alpha-tocopheryl quinone returned to the preischemic level. Lipid-derived malondialdehyde (a measure of lipid hydroperoxides) increased significantly only during reperfusion. The results suggest that oxidative stress occurs simultaneously with ischemia/reperfusion during aortic surgery, and that measurement of the tocopheryl quinone/tocopherol ratio may shed new light on the underlying pathological events.  相似文献   
25.
Recombinant bovine interferon-alpha(I)1 (rBolFN-alpha) may be useful for enhancing fertility in sheep because it has extensive sequence homology with ovine trophoblast protein-1. To test the effectiveness of rBolFN-alpha, several experiments were performed in which bred females were given intramuscular injections of rBolFN-alpha around the time of maintenance of the corpus luteum. Treatment with rBolFN-alpha enhanced the fertility of ewes that were bred via natural service or embryo transfer of whole or demi-embryos. Interferon treatment was successful in enhancing lambing rate if injections were given twice daily from Days 11 to 18, 12 to 14, 12 to 15 or 12 to 16. Overall, the lambing rate for ewes bred via natural service was 94/126 (74.6%) for control ewes and 101/126 (80.2%) for rBolFN-alpha treated ewes. Litter size was not affected by treatment. Interferon treatment was not successful in increasing the lambing rate if given as a single injection on Day 12 or as a series of once-daily injections from Days 11 to 16. These results demonstrate that rBolFN-alpha can increase the lambing rate in ewes.  相似文献   
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27.
Thirty-five honey-bee colonies, originally free fromVarroa jacobsoni (Oudemans) were monitored approximately every third week for the presence of the mite during 16 months following an initial introduction of five to eight adultVarroa females in early July. Investigations of hive debris detected the presence ofV. jacobsoni in 22 colonies (63%) within three months of the mite introduction. During the first winter period (October–April), mites were found in the hive debris of 13 colonies (37%). In terms of detectingVarroa during the summer in colonies with sealed brood, investigations of hive debris were more effective than sampling of brood. Brood sampling was more effective than sampling of live bees. In colonies without sealed brood, investigations of hive debris or of live bee samples seemed approximately equally efficient. The highest correlation between sampling methods was found between daily mite downfall and mites per live bee (r=0.81) in colonies with sealed brood. During the winter, investigations of dead bees and hive debris were approximately equally efficient in detectingVarroa.  相似文献   
28.
Biphasic changes in leukocytes induced by strenuous exercise   总被引:1,自引:0,他引:1  
Seven healthy male volunteers participated in short- (STR, 1.7 km), middle- (MTR, 4.8 km) and long- (LTR, 10.5 km) term runs at a speed close to their maximum. A prompt mobilization of white cells, and lymphocytes in particular, appeared following the exercise. The initial increase in the number of lymphocytes was succeeded by a significant decrease [(P less than 0.03) lymphopenial], which on average was 32%-39% of the pre-exercise values in all groups. A close correlation was found between the initial increase in plasma cortisol concentration after exercise and the subsequent lymphopenia. A modest enhancement in the number of granulocytes immediately after the exercise was accompanied by a comprehensive increase in polymorphonuclear (PMN) elastase concentration accounting for 78.6%, SEM 16.3%, 140.7%, SEM 31.8% and 241.3%, SEM 48.1% in the STR, MTR and LTR groups. No correlation was found between granulocyte number and the plasma PMN elastase concentration. A delayed granulocytosis was noted in all subjects, reaching a peak between 2 and 4 h after the exercise. The magnitude of the granulocytosis varied among subjects and peak values of the number of circulating granulocytes were found to be 5.7 x 10(9) cells.l-1, SEM 0.5, 6.7 x 10(9) cells.l-1, SEM 0.6 and 8.8 x 10(9) cells.l-1, SEM 0.5 in STR, MTR and LTR respectively, whereas the mean baseline value was 3.6 x 10(9) cells.l-1, SEM 0.4. The neutrophilic granulocytosis was not accompanied by a corresponding enhancement in PMN elastase concentration. The plasma cortisol concentration reached a peak 30 min after exercise and declined below the control level in 4 h. Neither the initial increase, nor the subsequent decrease in plasma cortisol concentration were found to be essential for the magnitude of the delayed leukocytosis.  相似文献   
29.
Familial porphyria cutanea tarda (PCT) results from a deficiency of uroporphyrinogen decarboxylase (URO-D) activity. Hybridization analysis of genomic DNA from unrelated normal individuals and PCT pedigree members failed to detect any major deletions, rearrangements or restriction fragment length polymorphisms at the URO-D locus.  相似文献   
30.
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