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991.
992.
Glycine uptake by erythrocytes from cases of iron deficiency anemia, megaloblastic anemia, and anemia of chronic renal failure and hypothyroidism has been studied. Concentrative uptake, characteristically observed only in iron deficiency, is dependent on a favorable Na+ gradient and is inhibited by p-chloromercuribenzoate. Transport appears to be mediated by a carrier whose possible relation to iron deficiency is discussed. 相似文献
993.
The tissue reactions in mice, experimentally infected with normal and irradiated cercariae of S. incognitum were studied. The lesions observed in the skin, liver, lungs and the intestine of mice infected with normal cercariae are briefly described, and compared with those observed with cercariae irradiated at 3000 r of gamma rays. In general, the reactions in mice exposed to normal cercariae were more intense than in those infected with irradiated cercariae. The severity of the reactions appeared largely due to the deposition of eggs in the tissues of the mice infected with normal cercariae. The experimental evidence suggested that most of the flukes from the irradiated cercariae are destroyed in the liver by tissue reaction. 相似文献
994.
Rohit Naniwadekar Abhishek Gopal Navendu Page Sartaj Ghuman Vivek Ramachandran Jahnavi Joshi 《Ecology and evolution》2021,11(3):1399
Endozoochory, a mutualistic interaction between plants and frugivores, is one of the key processes responsible for maintenance of tropical biodiversity. Islands, which have a smaller subset of plants and frugivores when compared with mainland communities, offer an interesting setting to understand the organization of plant–frugivore communities vis‐a‐vis the mainland sites. We examined the relative influence of functional traits and phylogenetic relationships on the plant–seed disperser interactions on an island and a mainland site. The island site allowed us to investigate the organization of the plant–seed disperser community in the natural absence of key frugivore groups (bulbuls and barbets) of Asian tropics. The endemic Narcondam Hornbill was the most abundant frugivore on the island and played a central role in the community. Species strength of frugivores (a measure of relevance of frugivores for plants) was positively associated with their abundance. Among plants, figs had the highest species strength and played a central role in the community. Island‐mainland comparison revealed that the island plant–seed disperser community was more asymmetric, connected, and nested as compared to the mainland community. Neither phylogenetic relationships nor functional traits (after controlling for phylogenetic relationships) were able to explain the patterns of interactions between plants and frugivores on the island or the mainland pointing toward the diffused nature of plant–frugivore interactions. The diffused nature is a likely consequence of plasticity in foraging behavior and trait convergence that contribute to governing the interactions between plants and frugivores. This is one of the few studies to compare the plant–seed disperser communities between a tropical island and mainland and demonstrates key role played by a point‐endemic frugivore in seed dispersal on island. 相似文献
995.
996.
Functionally distinct G proteins selectively couple different receptors to PI hydrolysis in the same cell 总被引:32,自引:0,他引:32
The number of G proteins identified by molecular cloning exceeds the number of known G protein functions. Here we show that a cell can possess multiple G proteins that carry out a similar function, the activation of phospholipase C, but couple selectively to different receptors, which are endogenous to the cell or introduced by DNA transfection. These G proteins (termed Gp) can be distinguished by their sensitivity to pertussis toxin. The assignment of a given Gp pathway to specific receptors is confirmed by the additivity relationships of the PI hydrolysis response mediated by the different receptors. Significantly different amounts of PI hydrolysis are activated through each Gp pathway, suggesting that Gp proteins also differ in their coupling to phospholipase C. These results indicate that distinct Gp pathways in a given cell exist to couple different receptors to PI hydrolysis selectively, and may specify the nature of the cellular response to different receptors by determining the magnitude of PI hydrolysis. 相似文献
997.
C Snehalatha A Ramachandran V Mohan H Timothy M Viswanathan 《Hormones et métabolisme》1986,18(6):391-394
Pancreatic beta cell function was assessed by estimation of fasting and post prandial plasma C-peptide in 183 non-insulin dependent diabetic patients, who were treated with oral hypoglycaemic drugs, for more than 10 years. One-hundred-and-forty-one patients, continued to respond to oral hypoglycaemic agents (Group I) and in 42 the control was not satisfactory and had to be changed over to insulin (secondary failure, Group II). Significant beta cell reserve (PP CP greater than or equal to 0.6 pmol/ml) was present in 89 out of 183 patients (48%) and 83 (93%) of them responded to oral hypoglycaemic agents. Among the 94 patients with low beta cell reserve, 58 (62%) were on oral hypoglycaemic agents and the other 36 (38%) were on insulin. Of the 42 patients with secondary failure to the oral drugs, 36 (86%) had low C-peptide while 6 (14%) had significant C-peptide values. Secondary failure to oral hypoglycaemic agents can also occur in spite of good beta cell reserve. Beta cell reserve was not correlated either to the duration of diabetes or the age at diagnosis of the patients. 相似文献
998.
IntroductionThe objective of this study was to examine the racial disparities in total ankle arthroplasty (TAA) utilization and outcomes.MethodsWe used the National Inpatient Sample (NIS) to study the time-trends. Race was categorized as White and Black. Utilization rates were calculated for the U.S. general population per 100,000. Hospital length of stay, discharge disposition and mortality after TAA were assessed. We used the Cochran Armitage trend test to assess time-trends from 1998 to 2011 and chi-square test to compare TAA utilization. We used analysis of variance or chi-squared test to compare the characteristics of Whites and Blacks undergoing TAA and logistic regression to compare mortality, length of stay and discharge to home versus medical facility.ResultsThe mean ages for Whites undergoing TAA were 62 years and for Blacks was 52 years. Significant racial disparities were noted in TAA utilization rates (/100,000) in 1998, 0.14 in Whites vs. 0.07 in Blacks (P < 0.0001; 2-fold) and in 2011, 1.17 in Whites vs. 0.33 in Blacks (P < 0.0001; 4-fold). Racial disparities in TAA utilization increased significantly from 1998 to 2011 (P < 0.0001). There was a trend towards statistical significance for the difference in the length of hospital stay in Blacks vs. Whites (52.9% vs. 44.3% with length of hospital stay higher than the median; P = 0.08). Differences in the proportion discharged to an inpatient medical facility after TAA, 16.6% Blacks vs. 13.4% Whites, were not significant (P = 0.36).ConclusionsThis study demonstrated significant racial disparities with lower TAA utilization and suboptimal outcomes in Blacks compared to Whites. Further studies are needed to understand the mediators of these disparities and to assess whether these mediators can be targeted to reduce racial disparities in TAA.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0589-2) contains supplementary material, which is available to authorized users. 相似文献999.
Summary The paper presents the results of measurements on tea samples collected during 1962 and 1973–1983 period for their natural radioactivity content. The radioisotopes studied under this programme are radium-226, thorium-228, and potassium-40. Tea was found to contain higher concentration of these radionuclides compared to other foodstuffs having vegetative origin. Interpretation for higher concentrations in tea compared to other foodstuffs is briefly given on the basis of agroclimatic conditions. 相似文献
1000.