Injection frontal

FIGURE 2. The effects of single and multiple injections of MDMA on the content of serotonin (5-HT) and 5-HIAA and the density of 5-HT uptake sites in rat frontal cerebral cortex... 

Ferric ion was immobilized on a Chelating Sepharose Fast Flow column preparatory to the separation of seven enkephalin-related phosphopep-tides.17 Non-phosphorylated peptides flowed through the column, and the bound fraction contained the product. The capacity of the column was found to be 23 pmol/mL by frontal elution analysis. Cupric ion was immobilized on Chelating Superose for the isolation of bovine serum albumin.18 Cupric ion was immobilized on a Pharmacia HiTrap column for the separation of Protein C from prothrombin, a separation that was used to model the subsequent apparently successful separation of Factor IX from prothrombin Factor IX activity of the eluate was, however, not checked.19 Imidazole was used as the displacement agent to recover p-galactosidase from unclarified homogenates injected onto a nickel-loaded IMAC column.20 Pretreatment with nucleases and cleaning in place between injections were required procedures. A sixfold purification factor was observed. 

Figure 7.8 Long-term effects of MDMA on tissue levels of 5-HT (left panel) and DA (right panel) in brain regions. Male rats received three i.p. injections of 1.5 or 7.5 mg/kg MDMA, one dose every 2 h. Saline was administered on the same schedule. Rats were killed 2 weeks after injections, brain regions were dissected, and tissue 5-HT and DA were assayed by HPLC-ECD.112 Data are mean SEM expressed as percent of saline-treated control values for each region, N = 5 rats/group. Control values of 5-HT and DA were 557 24 and 28 4 pg/mg tissue for frontal cortex (CTX), 429 36 and 10,755 780 pg/mg tissue for striatum (STR), and 1174 114 and 4545 426 pg/mg tissue for olfactory tubercle (OT). Significant compared to saline-injected control for each region (P < 0.05 Duncan s).

Fig. 20.2 Chronic lithium and valproate robustly increase bcl-2 immunoreactive neurons in the frontal cortex. Male Wistar Kyoto rats were treated with either Li2C03, valproate or saline by twice daily i.p. injections for four weeks. Rats brains were cut at 30 pm serial sections were cut coronally through the anterior portion of the brain, mounted on gelatin-coated glass slides and were stained with thio-nin. The sections of the second and third sets were incubated free-floating for 3 d at 4°C in 0.01 M PBS containing a polyclonal antibody against bcl-2 (N-19, Santa Cruz Biotechnology,...

Although separations may be caused by elution, frontal and displacement analyses, yet the elution technique is the most common. This method makes use of a stream of carrier-gas flowing through the column. Precisely, a sample is injected into the carrier-gas as a plug of vapour that is swept into the head of the packed chromatographic column. Separation of components that comprise the sample results from a difference in the multiple forces by which the column materials tend to retain each of the components. 

The effect of LSD on cerebral blood flow was studied in the rat (Goldman et al. 1975). An intravenous injection of LSD increased blood flow to frontal and parietal cortex within 10 minutes, and to the cerebellum within 20 minutes. Increases (significant or nonsignificant) were evidenced in all brain areas assessed, except for the hippocampus, where a minor, nonsignificant reduction was noted. 

Fig. 6.1 A breakthrough curve generated by the frontal analysis method [31], The analysis represents a high-volume injection of caffeine through a reversed-phase column, at a concentration representative of the linear region of the binding isotherm. Adapted with permission from Elsevier.

Fig. 6 Simulation of concentration distribution in frontal analysis capillary lenth 50 cm injection length 12.5 cm, corresponding 245 nL at 50-/j,m i.d. of capillary association constant 5000 M 1 initial concentration substrate 0.11 mM, ligand 0.1 mM mobility of substrate 10, of complex 40, of ligand 40 X 10-5 cm2V 1 B is 50 seconds after application of 25 kV.

Rapin et al. [11] have reported an increase of the acetylcholine synthesis rate constant evaluated by a bolus injection of [3H]choline in the hippocampus of 4-month-old rats after acute administration of EGb (100 mg/kg Lp.). Similar results were obtained in the frontal cortex, hippocampus and corpus striatum after chronic treatment with EGb (100 mg/kg/day p.o. for 21 days). On the other hand, the acetylcholine turnover rate was not modified by either acute or chronic administration of EGb. These results indicate that EGb might increase acetylcholine release. 

Four replicate columns were run, and all produced the same type of elution curve. Lyophilized samples of another aliquot of the same soil used in the columns yielded soil water with a tritium concentration the same as that in the first aliquot drawn from the column. The first aliquot was equivalent to 1 inch of rain on the column and represents about one-third of the free water in the original soil material in the column. Zimmerman (13) reported a similar phenomenon when he used tritiated water to trace pulses of rainwater in soil systems. He found a relatively discrete front associated with the tritium injection after rainfall had occurred and eluted the tritium pulse into the soil profile. The frontal movement of high specific activity tritiated water from the surface layers in ejecta strata Sedan accounts for the peak tritium concentrations observed at depths just below the maximum penetration of rainfall. 

A typical example of frontal polymerization is the polymerization of methyl methacrylate (or an oligomer), placed inside a long aluminum tube 249 these tubes continuously dip into a bath with a liquid heated up to temperature of 70 - 80°C. The part at the tubes above the bath are cooled so that the reactive material does not polymerize. Polymerization shrinkage is compensated by continuous injection of a monomer or oligomer into the reaction zone. The appropriate combination of injection rate, velocity of tube movement through the reaction zone, and tube diameter are chosen according to experimental studies of the process. 

An analysis of the temperature distribution in a mold (Fig. 4.54) at the final moment of filling for two reactive systems with different values of G shows that the temperature along the central line increases monotonically downstream (at distance x) from the inlet nozzle. At high values of the gelation criterion, the temperature at locations close to the injection nozzle is maximum near the mold wall. Moving down stream, the position of the temperature maximum shifts to the center, except at the frontal zone. Here the temperature is nearly constant, because the major part of the... 

Fig. 4. Schematic representation of electrokinetic sample injection in a a volume defined injection scheme (unbiased loading) and b conventional CE (biased sample loading). The sample migrates through the injection volume in a way resembling a frontal electropherogram...

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