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971.
Laura Fiorucci Gabriella De Renzis Rita Businaro Lorenzo Fumagalli Evandro Fioretti Bruno Giardina Franca Ascoli 《The Histochemical journal》1989,21(12):721-730
Summary Three isoinhibitors of bovine pancreatic trypsin inhibitor (BPTI) have been identified and isolated from bovine pituitary gland. The results of the purification process by affinity chromatography on immobilized trypsin, the electrophoretic mobility in non-denaturing conditions, the antiproteolytic activity and the immunochemical reactions indicate that these inhibitors correspond to those previously isolated from bovine spleen and lung. In addition, immunohistochemical experiments show that the isoinhibitors and BPTI are exclusively localized in the mast cells, and not in the endocrine cells, of the pars intermedia and posterior lobe (neurohypophysis) of the pituitary gland. The physiological implications of these findings are discussed. 相似文献
972.
Response of different decomposer communities to the manipulation of moisture availability: potential effects of changing precipitation patterns 总被引:1,自引:0,他引:1
Astrid Rita Taylor Dagmar Schröter† Anne Pflug Volkmar Wolters 《Global Change Biology》2004,10(8):1313-1324
The potential impacts of changes in precipitation patterns associated with global climate change on the relationship between soil community diversity and litter decomposition were investigated. For a period of ca. 5 months, two decomposer communities in litterbags (1000 and 45 μm mesh size) containing spruce litter were subjected to two irrigation treatments: constant and fluctuating (drying/rewetting) moisture conditions. The latter were expected to induce moisture stress on the decomposer communities. The two mesh sizes were used to exclude different faunal components from the decomposer communities. The 1000 μm mesh excluded only the macrofauna, whereas the 45 μm mesh excluded both the macro- and mesofauna. In the short-term perspective of the present study, mesofauna abundance showed no response to imposed fluctuating moisture conditions. Irrespective of the presence of mesofauna, mass loss, microbial biomass and the control mechanisms, regulating carbon mineralization appeared unaffected by fluctuating moisture conditions. The reduction in the functional/structural diversity of the decomposer communities in the 45 μm litterbags resulted in strongly increased Nematoda abundance but it did not alter the response of Nematoda to fluctuating moisture conditions. Processes in the nitrogen (N)-cycle and mass loss were sensitive indicators of changes in the structural and functional complexity of decomposer communities. However, a negative effect of fluctuating moisture conditions on extractable N was coupled to the presence of mesofauna. Extremes in rainfall patterns, generated by climate change, may have a negative impact on the availability of nutrients, particularly N, for plants. This effect could be amplified by an additional impoverishment in the structural and functional complexity of the respective decomposer communities. 相似文献
973.
Lee JC Weissglas-Volkov D Kyttälä M Dastani Z Cantor RM Sobel EM Plaisier CL Engert JC van Greevenbroek MM Kane JP Malloy MJ Pullinger CR Huertas-Vazquez A Aguilar-Salinas CA Tusie-Luna T de Bruin TW Aouizerat BE van der Kallen CC Croce CM Aqeilan RI Marcil M Viikari JS Lehtimäki T Raitakari OT Kuusisto J Laakso M Taskinen MR Genest J Pajukanta P 《American journal of human genetics》2008,83(2):180-192
Low serum HDL-cholesterol (HDL-C) is a major risk factor for coronary artery disease. We performed targeted genotyping of a 12.4 Mb linked region on 16q to test for association with low HDL-C by using a regional-tag SNP strategy. We identified one SNP, rs2548861, in the WW-domain-containing oxidoreductase (WWOX) gene with region-wide significance for low HDL-C in dyslipidemic families of Mexican and European descent and in low-HDL-C cases and controls of European descent (p = 6.9 × 10−7). We extended our investigation to the population level by using two independent unascertained population-based Finnish cohorts, the cross-sectional METSIM cohort of 4,463 males and the prospective Young Finns cohort of 2,265 subjects. The combined analysis provided p = 4 × 10−4 to 2 × 10−5. Importantly, in the prospective cohort, we observed a significant longitudinal association of rs2548861 with HDL-C levels obtained at four different time points over 21 years (p = 0.003), and the T risk allele explained 1.5% of the variance in HDL-C levels. The rs2548861 resides in a highly conserved region in intron 8 of WWOX. Results from our in vitro reporter assay and electrophoretic mobility-shift assay demonstrate that this region functions as a cis-regulatory element whose associated rs2548861 SNP has a specific allelic effect and that the region forms an allele-specific DNA-nuclear-factor complex. In conclusion, analyses of 9,798 subjects show significant association between HDL-C and a WWOX variant with an allele-specific cis-regulatory function. 相似文献
974.
Malm M Lindegårdh N Bergqvist Y 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,809(1):43-49
A bioanalytical method for the determination of piperaquine in 100 microL blood applied onto sampling paper, by solid-phase extraction and liquid chromatography, has been developed and validated. Blood spots were cut into small pieces prior to addition of 0.3M perchloric acid, acetonitrile and phosphate buffer containing an internal standard. The liquid phase was loaded onto a mixed phase cation-exchange (MPC) solid-phase extraction column. Piperaquine and the internal standard were analysed by liquid chromatography and separated on a Chromolith Performance (100 mm x 4.6 mm) column with acetonitrile:phosphate buffer pH 2.5, I = 0.1 (8:92, v/v) at the flow of 3.5 mL/min. The UV detection was performed at 345 nm. The intra-assay precision was 12.0% at 0.150 microM, 7.3% at 1.25 microM and 7.3% at 2.25 microM. The inter-assay precision was 1.8% at 0.150 microM, 5.2% at 1.25 microM and 2.8% at 2.25 microM. The lower limit of quantification (LLOQ) was determined to 0.050 microM where the precision was 14.7%. 相似文献
975.
Rita Mahapatra Dhananjay R. Patel 《Archives Of Phytopathology And Plant Protection》2013,46(2):120-134
Host defence mechanisms can be elicited by using different elicitors produced from the pathogen/host. In this study, an effort has been made to study the effect of two fungal elicitors derived from Aspergillus flavus and A. parasiticus on induction of various defence-related enzymes in maize (Zea mays L.). Foliar application was done on 20-days-old maize plant with 10% A. flavus fungal culture filtrate (AFFCF) and A. parasiticus fungal culture filtrate (APFCF) as elicitors to trigger systemic acquired resistance (SAR). As a response of SAR, an increase in activities of phenylalanine ammonia lyase (PAL), peroxidase (POX), β-1,3-glucanase, nitrate reductase (NR) and nitrite reductase (NiR), total proteins were found highest on 4th day after treatment (DAT), whereas total carbohydrate and total chlorophyll on 2nd and 6th DAT, respectively, in comparison with the control plants. The SDS PAGE analysis revealed the induction of PR proteins, namely Chitinase (25, 29?kDa) and β-1,3-glucanase (33?kDa), in treated plants in comparison with untreated control plants. The treated plants showed enhanced growth and development as well as increase in yield. About 100% survival rate was found in maize seeds treated with AFFCF and APFCF and grown on respective fungal infested soil than control. The enhanced activities of defence enzymes and elevated protein, carbohydrate, chlorophyll content in treated maize plants suggest the induction of SAR against A. flavus and A. parasiticus by using the same fungal elicitors. 相似文献
976.
Rita J. S. Phillips 《Molecular & general genetics : MGG》1954,86(3):322-326
Summary A new recessive mutant jimpy, jp, is described. It is situated on the differential segment of the sex chromosome and is lethal in the hemizygous condition. The jimpy mice show a behaviour disorder distinguished by an intention tremor first visible at about 11 days; after about three weeks they are liable to go into a convulsion if disturbed; death occurs usually between twenty-five and thirty-two days.
jp shows about 21% recombination with Ta and 36% with Bn. It has not been tested directly against Br and Mo, but they both have been shown to be about four units beyond Ta with respect to Bn (Falconer 1954). The presumed order is therefore Bn, Ta, Br and Mo, jp.Member of the Scientific Staff, Medical Research Council. 相似文献
977.
Molecular Genetics and Genomics - 相似文献
978.
Effect of forward acceleration on renal function 总被引:1,自引:0,他引:1
979.
The bleeding tendency in five members of one family with fibrinogen levels ranging from 58 mg. % to 158 mg. % was mild and chiefly related to dental extractions. Abruptio placentae in one patient produced severe bleeding. Reports of menstrual bleeding patterns in patients with defects of hemostatic mechanisms suggest that normal platelets, vascular function and extrinsic and possibly intrinsic coagulation systems, except for fibrinogen, control menstrual blood loss. An autosomal dominant gene with variable penetrance may determine fibrinogen levels. 相似文献
980.
Mammalian adrenodoxin (Adx) has been known for many years as an essential electron mediator in mitochondrial cytochrome P450 systems. Because of its ability to support several cytochrome P450 enzymes, it is involved not only in adrenal steroid hormone biosynthesis but also in vitamin D and bile acid metabolism. Recently, Adx is increasingly gaining attention because of its potential for pharmaceutical industry and biotechnology. With human cytochromes P450 becoming important drug targets, suitable Adx-based screening systems have to be developed to test putative new drugs. Moreover, in artificial systems, Adx has been shown to functionally interact with diverse bacterial cytochromes P450 catalyzing a variety of chemically interesting reactions. Putative biotechnological applications of such Adx-containing reconstituted systems are discussed. 相似文献