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951.
The effects of auxin on the inhibition of lateral buds in decapitated bean plants are enhanced if kinetin is applied together with auxin. The uptake of (14)C-indoleacetic acid by the stumps of decapitated plants is increased in the presence of kinetin and leads to extensive transport of (14)C-indoleacetic acid in the stems. The increased bud inhibition resulting when auxin and kinetin are applied together may be due to greater amounts of auxin reaching the buds, but an alternative explanation is that metabolites are directed from the buds to the point of hormone application. 相似文献
952.
Hominin fossils from the African mid-Pleistocene are rare despite abundant Acheulean tools in Africa and apparently African-derived hominins in Eurasia between 1.0 and 0.5 million years ago (Ma). Here we describe an African fossil cranium constrained by 40Ar/39Ar analyses, magnetostratigraphy, and sedimentary features to 0.97 to 0.90 Ma, and stratigraphically associated with Acheulean handaxes. Although the cranium represents possibly the smallest adult or near-adult known between 1.7 and 0.5 Ma, it retains features observed in larger Homo erectus individuals, yet shows a distinct suite of traits indicative of wide population variation in the hominins of this period. 相似文献
953.
Lee KH Dinner AR Tu C Campi G Raychaudhuri S Varma R Sims TN Burack WR Wu H Wang J Kanagawa O Markiewicz M Allen PM Dustin ML Chakraborty AK Shaw AS 《Science (New York, N.Y.)》2003,302(5648):1218-1222
The immunological synapse is a specialized cell-cell junction between T cell and antigen-presenting cell surfaces. It is characterized by a central cluster of antigen receptors, a ring of integrin family adhesion molecules, and temporal stability over hours. The role of this specific organization in signaling for T cell activation has been controversial. We use in vitro and in silico experiments to determine that the immunological synapse acts as a type of adaptive controller that both boosts T cell receptor triggering and attenuates strong signals. 相似文献
954.
Klein RJ Zeiss C Chew EY Tsai JY Sackler RS Haynes C Henning AK SanGiovanni JP Mane SM Mayne ST Bracken MB Ferris FL Ott J Barnstable C Hoh J 《Science (New York, N.Y.)》2005,308(5720):385-389
Age-related macular degeneration (AMD) is a major cause of blindness in the elderly. We report a genome-wide screen of 96 cases and 50 controls for polymorphisms associated with AMD. Among 116,204 single-nucleotide polymorphisms genotyped, an intronic and common variant in the complement factor H gene (CFH) is strongly associated with AMD (nominal P value <10(-7)). In individuals homozygous for the risk allele, the likelihood of AMD is increased by a factor of 7.4 (95% confidence interval 2.9 to 19). Resequencing revealed a polymorphism in linkage disequilibrium with the risk allele representing a tyrosine-histidine change at amino acid 402. This polymorphism is in a region of CFH that binds heparin and C-reactive protein. The CFH gene is located on chromosome 1 in a region repeatedly linked to AMD in family-based studies. 相似文献
955.
956.
Abayeh OJ Abdulrazaq AK Olaogun R 《Plant foods for human nutrition (Dordrecht, Netherlands)》1999,54(1):43-48
The oil content and quality characteristics of Canarium schweinfurthii Engl. oil are described. The oils were extracted from the mesocarp and endocarp using hexane to remove the free flowing lipid (FFL) and successive extraction with CHCl3-MeOH followed by water saturated butanol to remove bound lipid (BL). On a dry matter basis, the mesocarp contained 68.3% FFL and 13.7% BL while the endocarp contained 67.0% FFL and 13.0% BL. The quality characteristics of the mesocarp oil extracts were 151.9–195.3 mg KOH/g fat saponification value (SV), 20–40 mEq peroxide/kg fat peroxide value (PV), 71.1–94.9 g iodine/100 g fat iodine value (IV) and 1.33–8.30 mg KOH acid value (AV). Characteristics for the endocarp oil extracts were 95.4–184.3 mg KOH/g fat SV, 4.0–8.0 mEq peroxide/kg fat PV, 100.1–118.3 g iodine/100 g fat IV, and AV of 0.48–8.70 mg KOH. The fatty acid composition of the first hexane extracts indicated that the oils were primarily C16 and C18s. The mesocarp contained 31.7% hexadecanoic acid, 30.0% 9-octadecenoic acid, 30.1% 6,9-octadecadienoic acid and 8.2% 9,12,15-octadecatrienoic acid, while the endocarp, contained 31.2% hexadecanoic acid, 28.9% 9-octadecenoic acid and 31.3% 6,9-octadecadienoic acid. 相似文献
957.
Modulatory Effect of Fenugreek Seed Mucilage and Spent Turmeric on Intestinal and Renal Disaccharidases in Streptozotocin Induced Diabetic Rats 总被引:1,自引:0,他引:1
Kumar GS Shetty AK Salimath PV 《Plant foods for human nutrition (Dordrecht, Netherlands)》2005,60(2):87-91
To elucidate the effect of feeding fenugreek seed mucilage and spent turmeric (10%) on disaccharidases activities, the specific activities of intestinal and renal disaccharidases viz., sucrase, maltase and lactase were measured in streptozotocin induced diabetic rats. Specific activities of intestinal disaccharidases were increased significantly during diabetes and amelioration of these activities during diabetes was clearly visible by supplementing fenugreek seed mucilage and spent turmeric in the diet. However during diabetes renal disaccharidases activities were significantly lower than those in the control rats. Fenugreek seed mucilage and spent turmeric supplementations were beneficial in alleviating the reduction in maltase activity during diabetes, however not much change in the activities of sucrase and lactase was observed upon feeding. This positive influence of feeding fenugreek seed mucilage and spent turmeric on intestinal and renal disaccharidases clearly indicates their beneficial role in the management of diabetes. 相似文献
958.
Rajamäki MM Järvinen AK Sorsa T Maisi P 《Veterinary journal (London, England : 1997)》2002,163(2):168-181
We characterized clinical and clinicopathological features, and the involvement of gelatinolytic matrix metalloproteinases (MMP-2 and -9) in canine pulmonary eosinophilia (PE). Study material consisted of 20 PE dogs and 16 healthy beagles. All dogs underwent a similar clinical examination and bronchoalveolar lavage (BAL). Analysis for cell count and differential cell count of BAL fluid (BALF), arterial blood gas analysis before and after BAL, and thoracic radiographs before BAL and after treatment were obtained. Twelve dogs were re-evaluated and six relavaged. MMP-2 and MMP-9 in BALF were analysed by zymography, Western immunoblotting and immunocytochemistry.In the PE dogs, BALF, cell count, number and percentage of eosinophils, and numbers of macrophages, lymphocytes, neutrophils, mast cells and epithelial cells were all significantly elevated. Blood eosinophilia was detected in half of the PE dogs. Three PE dogs had mild hypoxaemia. The BAL procedure had an equal effect on PE and healthy dogs' arterial blood gas values. Bronchointerstitial densities were seen in PE dogs' radiographs. Treatment of PE decreased BALF cell count, eosinophil count and percentage and diminished radiographic changes. Gelatinolytic activity was higher in PE dogs' BALF. BALF macrophages and epithelial cells were the principal sources of the MMP-9. 相似文献
959.
Direct and maternal (co)variance components and genetic parameters for growth and reproductive traits in the Boran cattle in Kenya 总被引:2,自引:2,他引:0
Direct and maternal (co)variance components and genetic parameters were estimated for growth and reproductive traits in the
Kenya Boran cattle fitting univariate animal models. Data consisted of records on 4502 animals from 81 sires and 1010 dams
collected between 1989 and 2004. The average number of progeny per sire was 56. Direct heritability estimates for growth traits
were 0.34, 0.12, 0.19, 0.08 and 0.14 for birth weight (BW), weaning weight (WW), 12-month weight (12W), 18-month weight (18W)
and 24-month weight (24W), respectively. Maternal heritability increased from 0.14 at weaning to 0.34 at 12 months of age
but reduced to 0.11 at 24 months of age. The maternal permanent environmental effect contributed 16%, 4% and 10% of the total
phenotypic variance for WW, 12W and 18W, respectively. Direct-maternal genetic correlations were negative ranging from −0.14
to −0.58. The heritability estimates for reproductive traits were 0.04, 0.00, 0.15, 0.00 and 0.00 for age at first calving
(AFC), calving interval in the first, second, and third parity, and pooled calving interval. Selection for growth traits should
be practiced with caution since this may lead to a reduction in reproduction efficiency, and direct selection for reproductive
traits may be hampered by their low heritability. 相似文献
960.
An indirect enzyme-linked immunosorbent assay (iELISA) was evaluated for its diagnostic capability in detecting antibodies against Fasciola gigantica infection in cattle, sheep and donkeys sera using crude worm, excretory–secretory and glutathione S-transferase antigens prepared from adult liver fluke. Presence of F. gigantica worms at post-mortem examination of cattle, sheep and donkey’s livers was taken as a gold standard for the evaluation of the assay. The diagnostic sensitivity, specificity and accuracy percentages of iELISA were determined for each antigen. Excretory–secretory antigen gave the best results for the serodiagnosis of F. gigantica infection in cattle, sheep and donkeys using iELISA with diagnostic sensitivity percentages of 93.3%, 94.9% and 93.3%, respectively, while the specificity percentages were 96.7%, 97.2% and 96.3%, respectively, whereas the accuracy percentages were 95%, 96% and 95.7%, respectively. The diagnostic sensitivity percentages of iELISA using crude worm antigen were 96.7%, 100% and 93.3%, respectively, while the specificity percentages were 80%, 83.3% and 85.2%, respectively, whereas the accuracy percentages were 88.3%, 86.7% and 87%, respectively. The diagnostic sensitivity percentages of iELISA using glutathione S-transferase antigen were 66.7%, 71.8% and 60%, respectively, while the specificity percentages were 70%, 77.8% and 77.8%, respectively, whereas the accuracy percentages were 68.3%, 74.7% and 73.9%, respectively. Conclusively, excretory–secretory antigen dependent iELISA can be used as a reliable serodiagnostic test for F. gigantica infection in cattle, sheep and donkeys. 相似文献