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81.
Srivastava S Terjung RL Yang HT 《American journal of physiology. Heart and circulatory physiology》2003,285(3):H1190-H1197
Ischemia-induced angiogenic response is reduced in spontaneously hypertensive rats (SHR). To study whether exogenous basic fibroblast growth factor (bFGF) infusion is effective in expanding collateral circulation in frankly hypertensive SHR, femoral arteries of male SHR (weighing approximately 250 g) were kept intact (nonoccluded control; n = 9) or occluded for 4h(n = 12) or for 16 days with vehicle (n = 14) or bFGF [0.5 (n = 17), 5.0 (n = 13), and 50.0 (n = 14) microg. kg-1. day-1 for 14 days] intraarterially. Maximal collateral-dependent blood flows (BF) to the hindlimbs were determined with 85Sr- and 141Ce-labeled microspheres during running at 20 and 25 m/min (15% grade). Preexercise heart rates (approximately 530 beats/min) and blood pressures (BP; approximately 200 mmHg) were similar across groups except in the high-dose bFGF group, where BP was reduced by approximately 12% (P < 0.05). Femoral artery occlusion for 4 h resulted in approximately 95% reduction of BF in calf muscles [199 +/- 18.7 (nonoccluded group) to 10 +/- 1.0 ml. min-1. 100 g-1; P < 0.001]. BF to calf muscles of the vehicle and low-dose bFGF (0.5 microg. kg-1. day-1) groups increased to 36 +/- 3.2 and 45 +/- 2.0 ml. min-1. 100 g-1, respectively (P < 0.001). bFGF infusion at 5.0 and 50.0 microg. kg-1. day-1 further increased (P < 0.001) BF to calf muscles (62 +/- 4.6 and 62 +/- 2.2 ml. min-1. 100 g-1, respectively). Our results show that bFGF can effectively increase BF in hypertensive rats. The reduced hypertension with high-dose bFGF suggests that a critical signal in arteriogenesis (nitric oxide bioavailability) may be restored. These findings suggest that the dulled endothelial nitric oxide synthase of SHR does not preempt collateral vessel remodeling. 相似文献
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83.
Diversity of the native diazotrophs associated with the rhizosphere of pearl millet (P. glaucumn), grown in nutritionally poor soils of semi-arid regions was studied with a view to isolate effective nitrogen fixing and plant growth stimulating bacteria with root associative characteristics. The native population varied from 10(3)-10(4) g(-1) of rhizosphere soil after 40 d growth and belonged to genera Azospirillum, Azotobacter and Klebsiella. Another non-diazotrophic root associative group was Pseudomonas sp., which also produced IAA and enhanced plant growth. Some of these rhizobacteria showed high in vitro acetylene reduction activity along with production of indole acetic acid. Out of 11 selected diazotrophs used as seed inoculants, M10B (Azospirillum sp.), M11E (Azotobacter sp.) and M12D4 (Klebsiella sp.) resulted in significant increase in total root and shoot nitrogen at 45 and 60 days of plant growth under pot culture conditions. 相似文献
84.
Quantitative trait loci on chromosomes 1, 2, 3, 4, 8, 9, 11, 12, and 18 control variation in levels of T and B lymphocyte subpopulations 总被引:5,自引:0,他引:5 下载免费PDF全文
Hall MA Norman PJ Thiel B Tiwari H Peiffer A Vaughan RW Prescott S Leppert M Schork NJ Lanchbury JS 《American journal of human genetics》2002,70(5):1172-1182
Lymphocyte subpopulation levels are used for prognosis and monitoring of a variety of human diseases, especially those with an infectious etiology. As a primary step to defining the major gene variation underlying these phenotypes, we conducted the first whole-genome screen for quantitative variation in lymphocyte count, CD4 T cell, CD8 T cell, B cell, and natural killer cell numbers, as well as CD4:CD8 ratio. The screen was performed in 15 of the CEPH families that form the main human genome genetic project mapping resource. Quantitative-trait loci (QTLs) that account for significant proportions of the phenotypic variance of lymphocyte subpopulations were detected on chromosomes 1, 2, 3, 4, 8, 9, 11, 12, and 18. The most significant QTL found was for CD4 levels on chromosome 8 (empirical P=.00005). Two regions of chromosome 4 showed significant linkage to CD4:CD8 ratio (empirical P=.00007 and P=.003). A QTL for the highly correlated measures of CD4 and CD19 levels colocalized at 18q21 (both P=.003). Similarly, a shared region of chromosome 1 was linked to CD8 and CD19 levels (P=.0001 and P=.002, respectively). Several of the identified chromosome regions are likely to harbor polymorphic candidate genes responsible for these important human phenotypes. Their discovery has important implications for understanding the generation of the immune repertoire and understanding immune-system homeostasis. More generally, these data show the power of an integrated human gene-mapping approach for heritable molecular phenotypes, using large pedigrees that have been extensively genotyped. 相似文献
85.
Goswami PP Girish KS Chaudhuri P Tiwari V Akare SJ Harbola PC 《Indian journal of experimental biology》2002,40(1):109-110
A gene encoding beta toxin was amplified by polymerase chain reaction from C. perfringens type C isolate and cloned in pUC 19 vector. The nucleotide sequence was identical with C. perfringens type B beta toxin gene sequence. The Southern hybridization using labelled beta toxin gene probe revealed the presence of positive signals only in beta producing C. perfingens. 相似文献
86.
Tiwari R Priyamvada Singh R Nainawatee HS Kumar R Tyagi BS Gupta RK Nagarajan S 《Indian journal of experimental biology》2002,40(3):309-313
Detection of 1Dx5 gene and presence of 1B/1R wheat rye translocation were studied in nineteen elite Indian wheat genotypes using AS-PCR and STS markers, respectively. Fifteen genotypes had 1B/1R translocation whereas ten showed presence of 1Dx5 gene. More than 50 per cent of the genotypes tested were found positive for both 1Dx5 and 1B/1R translocation. The results are in conformity with HMW glutenin SDS-PAGE profile for 1Dx5 and cytological observations for 1B/1R translocation. 相似文献
87.
88.
An improved micropropagation protocol has been developed for teak (Tectona grandis). Nodal explants placed on MS medium supplemented with 22.2 M benzylaminopurine and then serially transferred to fresh medium after 12, 24, 48 and 72 h gave maximum culture establishment (76.8%). Establishment was reduced when explants were retained in the initial culture medium longer than 12 h. Explants collected in May showed maximum (76.8%) response. Placement of the explants on MS medium supplemented with 22.2 M benzylaminopurine and 0.57 M indole-3-acetic acid resulted in the maximum average number of shoots. In vitro raised micro shoots were rooted ex vitro by dipping in indole-3-butyric acid (9.8 mM) for 2 min followed by planting in polyethylene pots containing a soil:vermiculite (1:1 v/v) mixture. This treatment resulted in 77.9% survival of the plantlets. They were weaned in a glasshouse and finally moved to an agro-net shade house. 相似文献
89.
Chen YG Ashok BT Liu X Garikapaty VP Mittelman A Tiwari RK 《Cell stress & chaperones》2003,8(3):242-248
90.
A bioconjugate of -chymotrypsin and Eudragit S-100 was used in an aqueous two-phase system (polyethylene glycol/phosphate) for casein hydrolysis. More product was obtained by replacing the lower salt phase with a fresh one during the reaction. The bioconjugate could be reused six times for casein hydrolysis. 相似文献