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41.
42.
A new simple and rapid method for immunochemical quantitation called immunocapillarymigration is described. It is based upon the attachment of antibodies to a porous insoluble support and the subsequent capillarymigration of the antigen-containing solution in the porous support. The migration of the antigen solute is specifically delayed in comparison to the migration of the solvent and other solutes in the process and the relative delay decreases with increasing antigen concentration. When applied to the quantitation of transferrin in human plasma, immunocapillarymigration gave results which agreed with those obtained by single radial immunodiffusion. 相似文献
43.
A DNA variation in the coding region of the human cystatin C gene has been detected by direct sequencing. The polymorphism, a G/A transition, leads to an Ala/Thr variation in the penultimate amino acid of the signal peptide. The base substitution results in the loss of a SstII restriction site, thus allowing the design of a rapid polymerase chain reaction assay for analysis of this polymorphism in the population. 相似文献
44.
EO Ogueji CD Nwani SC Iheanacho CE Mbah CO Okeke A Yaji 《African Journal of Aquatic Science》2018,43(3):293-303
Indiscriminate discharge of pharmaceutical waste into the aquatic ecosystem may pose serious health challenges to aquatic biota. The effect of acute exposure to ibuprofen was evaluated using changes in behaviour and haematological parameters under static bio-assay method in Clarias gariepinus. Test specimens were exposed to acute concentrations of ibuprofen (0.28, 0.33, 0.38, 0.43 and 0.48 mg l?1) for 24, 48, 72 and 96 h durations respectively. Behavioural and phenotypic changes were observed in surviving fish. There were significant (p < 0.05) concentration and duration-dependent increases in erythrocyte (RBC), haemoglobin (Hb), pack cell volume (PCV) and leukocytes (WBC) in treated fish compared to the control. Insignificant decreases (p > 0.05) in mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were observed in treated fish compared to the control. Ibuprofen elicited dose and duration- dependent decrease in neutrophil counts with the decreases being significant (p < 0.05) in the higher doses of 0.43 and 0.48 mg l?1. Ibuprofen did not elicit any significant changes in monocytes, basophils and eosinophils. Changes observed in this study showed that ibuprofen negatively affected the health of the fish and we recommend that discharge of ibuprofen into the aquatic environment should be monitored and controlled. 相似文献
45.
Regional and local patterns in plant species richness with respect to resource availability 总被引:6,自引:0,他引:6
The hump-shaped relationship between plant species richness and productivity is a well-established and important paradigm. While plot-based species richness patterns on local scales have received much attention, little is currently known about species-based patterns on a regional scale. Using Ellenberg's indicator values for 1802 plant species in central Europe, we assess the patterns in regional species richness with respect to light, water, and mineral nutrient availability – three variables that strongly influence productivity. The results of this analysis are compared to those of published studies on smaller scales leading to the following conclusions:
- 1.
On a regional scale in central Europe there is a hump-shaped relationship between soil nutrient supply and plant species richness within a given biome.
46.
47.
Carl R Harrington Sacha Lucchini Karyn P Ridgway Udo Wegmann Tracy J Eaton Jay CD Hinton Michael J Gasson Arjan Narbad 《BMC microbiology》2008,8(1):195
Background
The human gastrointestinal (GI) tract contains a diverse collection of bacteria, most of which are unculturable by conventional microbiological methods. Increasingly molecular profiling techniques are being employed to examine this complex microbial community. The purpose of this study was to develop a microarray technique based on 16S ribosomal gene sequences for rapidly monitoring the microbial population of the GI tract. 相似文献48.
Troponin elevation is usually synonymous with acute coronary syndrome (ACS). Although sensitive for ACS, the elevation of serum troponin, in the absence of clinical evidence of ischemia, should prompt a search for other etiologies of myocardial necrosis. In fact, elevated values of troponin are correlated with myocardial necrosis even though it does not discriminate the mechanism involved. We report a series of seven patients (age range 18-67 years), who presented with complaints of chest discomfort and were found to have regular supraventricular tachycardia (5 patients) and one patient each with atrial fibrillation and ventricular tachycardia. All these patients had elevated troponin I and underwent coronary angiography that revealed normal epicardial coronary arteries. This is first case series in which all patients underwent coronary angiography and none of the patients was hemodynamically unstable at the time of presentation. Patients with elevated troponin due to conditions other than ACS can receive inappropriate and delayed definitive diagnosis and treatment. 相似文献
49.
Scorza T Grubb K Cambos M Santamaria C Tshikudi Malu D Spithill TW 《International journal for parasitology》2008,38(7):819-827
A current goal of malaria vaccine research is the development of vaccines that will cross-protect against multiple strains of malaria. In the present study, the breadth of cross-reactivity induced by a 30K multivalent DNA vaccine has been evaluated in susceptible A/J mice (H-2a) against infection with the Plasmodium chabaudi adami DK strain and a virulent parasite subspecies, Plasmodium chabaudi chabaudi AS. Immunized A/J mice were significantly protected against infection with both P. c. adami DK (31–40% reduction in cumulative parasitemia) and P. c. chabaudi AS parasites, where a 30–39% reduction in cumulative parasitemia as well as enhanced survival was observed. The 30K vaccine-induced specific IFN-γ production by splenocytes in response to native antigens from both P. c. chabaudi AS and P. c. adami DK. Specific antibodies reacting with surface antigens expressed on P. c. adami DS and P. c. chabaudi AS infected red blood cells, and with opsonizing properties, were detected. These results suggest that multivalent vaccines encoding conserved antigens can feasibly induce immune cross-reactivity that span Plasmodium strains and subspecies and can protect hosts of distinct major histocompatibility complex haplotypes. 相似文献
50.
Six features are covered. (1) The high endemism, which is not discussed in detail, is all-pervasive, and has resulted from the isolation of Madagascar from Africa some 125 million years ago and their present separation by 430 km. (2) The great richness in plant species (especially relative to Africa), seen particularly in the families of woody species in the wetter vegetation-types, involves both sympatry and allopatry within genera, and is explicable in terms of much less extreme drying out than in Africa during the Pleistocene and effective ‘species-pumping’ rather than mass extinctions during that period. (3) The abundance and species-richness of palms, pandans, tree-ferns, bamboos, and certain families of dicot trees (notably Lauraceae, Monimiaceae, Myrsinaceae and Myristicaceae) in the lowland rain forests also appears to be a result of both past and present wetness of the climate, while it is hypothesized that the low stature of most lowland rain forests, paucity of large-girth trees, and small size and sparsity of broad-leaved herbs, are a result of most rain forest soils being old and relatively nutrient-poor. (4) Within the dry evergreen forest region where rainfall is moderate (900–1600 mm yr−1) a sub-set of trees with fire-resistant bark seems to have evolved at sites prone to frequent ground fires, some perhaps spreading out of adjacent palm savanna on seasonally flooded sites. (5) Both the evolution of thicket rather than grassy woodland in the driest areas (300–600 mm yr−1), and the abundance of evergreen trees and shrubs on ordinary soils – not confined to run-on sites – are explicable in terms of there being a finite chance of rain throughout the year rather than one short wet season, coupled with relatively high values for air humidity throughout the year. The same factors probably explain the abundance and variety of succulents in the thicket; they are found throughout and not just on rocks. (6) Concerning physical defence against herbivores, the rain forests, dry evergreen forests and deciduous forests all show a complete lack of plants with physiognomic features plausibly related to browsing by extinct giant birds (a strong contrast with New Zealand), but in the semi-deciduous thicket there are many tiny-leaved, mostly non-spiny shrubs and small trees, whose dense branching and impenetrability have plausibly evolved as a defence against browsing by elephant birds. The Didiereaceae of the thicket are spiny (unlike members of the same family in Africa), and are giant analogues of the ‘ocotillo’ (Fouquieria splendens) in western North America rather than of Cactaceae; their spines appear to be protecting the leaves more than the stems against arboreal primates, spine length paralleling leaf length. 相似文献