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81.
BT Kang 《Nutrient Cycling in Agroecosystems》1984,5(4):403-410
Results of three consecutive croppings to study the potassium and magnesium responses of two improved cassava cultivars TMS 30395 and 30211 grown on an acid, sandy loam, Ultisol (Typic paleudult) in southern Nigeria is reported. On land newly cleared from Eupatorium fallow a significant potassium response in the first cropping year was observed only with the more vigorous cultivar TMS 30395. Both cultivars responded to potassium applications at rates of 30 and 60 kg Kha–1 in second and third croppings respectively. A significant response to application of 20 kg Mgha–1 was observed in the third crop with cultivar TMS 30211. Cultivar TMS 30395 seems to be more effective in utilizing magnesium from the soil. Potassium and magnesium responses on this Ultisol can be expected when the IN Ammonium Acetate extractable soil K and Mg test levels are 0.15 me K 100g–1 and 0.20 meMg 100g–1, respectively. Critical tissue concentrations of cassava index leaves sampled at 6 MAP are 0.1% K for both cultivars and 0.33% Mg for cultivar TMS 30211. 相似文献
82.
Investigated the influence of the lateral connections of the medial preoptic area (MPOA) on maternal behavior via the substantia nigra (SN). In Exp I, conducted with 45 postpartum lactating Charles River CD rats, the effects of large and small bilateral electrolytic lesions of SN were investigated. Large lesions severely disrupted maternal behavior and caused stereotyped activity in Ss. A 2nd experiment employed an asymmetrical lesion design and 37 Ss. Ss that received a unilateral knife cut severing the lateral connections of the MPOA and a contralateral lesion of the SN showed larger deficits in maternal behavior than either sham Ss or Ss that received a unilateral preoptic cut paired with an ipsilateral SN lesion. Measurements of body weights, body temperatures, and stereotyped behavior indicated that the differences in maternal behavior between the ipsilateral and contralateral groups could not be explained on the basis of nonspecific effects. (57 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
BT Jackson 《Canadian Metallurgical Quarterly》1977,64(4):255-257
A detailed and illustrated account is given of the surgical operation needed to treat practolol-induced sclerosing peritonitis, based on the personal experience of 6 patients. 相似文献
84.
IgA class reticulin antibodies were not found in patients with Crohn's disease, ulcerative colitis, and hiatus hernia despite a significant incidence of IgG class reticulin antibodies. None of 56 normal healthy subjects was positive. In contrast, 13 (76%) of the sera from 17 patients with coeliac disease on normal diet were positive for IgA class antibodies as were 19 (20%) of 93 first degree relatives. Seventy-three relatives underwent jejunal biopsy. Grade III (flat) histology was found in 13 and, of these patients, 10 (77%) showed IgA class reticulin antibody in their serum. It is suggested that determination of IgA class reticulin antibodies was a useful test to determine which relative must be biopsied. 相似文献
85.
86.
BT Pentecost 《Canadian Metallurgical Quarterly》1998,64(1-2):25-33
The combination of manual and automated extraction procedures using low sample volumes (5-50 ml) with large-volume oncolumn injection (LVI) (200 microliters) in capillary gas chromatography with flame photometric detection (GC-FPD) has allowed the determination of 16 organophosphorus pesticides in clean water samples at the low ng l-1 level with an important simplification in the sample preparation step. A simple and fast offline liquid-liquid microextraction procedure (2-5 ml water/l ml methyl tert.-butyl ether) has been applied to spiked groundwater samples (containing 0.5 ng of each pesticide) with good recoveries (over 80%) and precision (better than 10%), giving detection limits between 5 and 100 ng l-1 using 200 microliters injections in the GC-FPD system. The application of an inline automated liquid-liquid microextraction-LVI-GC procedure (2 ml water/2 ml methyl tert.-butyl ether: injection of 200 microliters in GC-FPD) using the autosampler ASPEC XL led to lower recoveries (> 50%) as a result of the low efficiency for mixing organic and aqueous phases, although with very satisfactory coefficients of variation (lower than 7%) and detection limits between 20 and 200 ng l-1. Manual and automated solid-phase extraction procedures using the well known C18 cartridges and the new Oasis HLB have been applied to groundwater samples (5-50 ml) spiked with 1 ng of each pesticide. Results obtained for both the manual and the automated procedures were satisfactory (recoveries over 80%) and the limits of detection for 50 ml sample volume ranged from 1 to 6 ng l-1. 相似文献
87.
LP Morssink BT de Wolf LH Kornman JR Beekhuis TP van der Hall A Mantingh 《Canadian Metallurgical Quarterly》1996,103(8):779-783
To disclose the cytoprotective mechanism of 1,6-dihydro-2[2-(2-methyoxypropoxy)anilino]-6-oxo-5-pyrimidinecarb oxylic acid (CAS 98772-05-5, MAR-99), the effect of this compound on the microvascular injury in gastric mucosa induced by 99.5% ethanol in rats was studied. In this experiment, it was found that the elevation of vascular permeability observed at the early state of ethanol-induced gastric mucosal injury was closely correlated with the combined action of histamine and slow reacting substance (leukotriene C4, LTC4). MAR-99 (0.3-10 mg/kg p.o.) prevented dose-dependently the increase in vascular permeability. Furthermore, MAR-99 (10 mg/kg p.o.) improved the decrease in the number of histamine containing cells and histamine content, and prevented the production of LTC4. These results suggest that MAR-99 exerts its anti-microvascular injury effect by regulating the release of histamine and the production of LTC4 in glandular stomach against ethanol, and this effect may contribute to the anti-lesion effect of this compound. 相似文献
88.
89.
90.
RI Connor BT Korber BS Graham BH Hahn DD Ho BD Walker AU Neumann SH Vermund J Mestecky S Jackson E Fenamore Y Cao F Gao S Kalams KJ Kunstman D McDonald N McWilliams A Trkola JP Moore SM Wolinsky 《Canadian Metallurgical Quarterly》1998,72(2):1552-1576
We have studied 18 participants in phase I/II clinical trials of recombinant gp120 (rgp120) subunit vaccines (MN and SF-2) who became infected with human immunodeficiency virus type 1 (HIV-1) during the course of the trials. Of the 18 individuals, 2 had received a placebo vaccine, 9 had been immunized with MN rgp120, and seven had been immunized with SF-2 rgp120. Thirteen of the 18 infected vaccinees had received three or four immunizations prior to becoming infected. Of these, two were placebo recipients, six had received MN rgp120, and five had received SF-2 rgp120. Only 1 of the 11 rgp120 recipients who had multiple immunizations failed to develop a strong immunoglobulin G antibody response to the immunogen. However, the antibody response to rgp120 was transient, typically having a half-life of 40 to 60 days. No significant neutralizing activity against the infecting strain was detected in any of the infected individuals at any time prior to infection. Antibody titers in subjects infected despite vaccination and in noninfected subjects were not significantly different. Envelope-specific cytotoxic T-lymphocyte responses measured after infection were infrequent and weak in the nine vaccinees who were tested. HIV-1 was isolated successfully from all 18 individuals. Sixteen of these strains had a non-syncytium-inducing (NSI) phenotype, while two had a syncytium-inducing (SI) phenotype. NSI strains used the CCR5 coreceptor to enter CD4+ cells, while an SI strain from one of the vaccinees also used CXCR4. Viruses isolated from the blood of rgp120 vaccinees were indistinguishable from viruses isolated from control individuals in terms of their inherent sensitivity to neutralization by specific monoclonal antibodies and their replication rates in vitro. Furthermore, genetic sequencing of the env genes of strains infecting the vaccinees did not reveal any features that clearly distinguished these viruses from contemporary clade B viruses circulating in the United States. Thus, despite rigorous genetic analyses, using various breakdowns of the data sets, we could find no evidence that rgp120 vaccination exerted selection pressure on the infecting HIV-1 strains. The viral burdens in the infected rgp120 vaccine recipients were also determined, and they were found to be not significantly different from those in cohorts of placebo-vaccinated and nonvaccinated individuals. In summary, we conclude that vaccination with rgp120 has had,to date, no obvious beneficial or adverse effects on the individuals we have studied. 相似文献