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81.
In Argentina, 10 genera and 33 species of Stenopodainae (Hemiptera: Reduviidae) have been recorded. Diagnoses of the genera, subgenera and species are given, and an illustrated key to genera is provided. Six species are new records for Argentina and an additional seven species represent new records for provinces. 相似文献
82.
Rosa Gómez M. Isabel Arce J. Javier Sánchez M. del Mar Sánchez-Montoya 《Hydrobiologia》2012,679(1):43-59
Mediterranean climates predispose aquatic systems to both flood and drought periods, therefore, stream sediments may be exposed
to desiccation periods. Changes in oxygen concentrations and sediment water content influence the biotic processes implicated
in nitrogen dynamics. The objectives of this study were to identify (1) the changes of inorganic nitrogen in stream sediments
during the transition from wet to dry conditions, and (2) the underlying processes in N dynamics and its regulation. Extractable
sediment NO3
−-N and NH4
+-N, organic matter and extractable organic carbon content were assessed during natural desiccation in microcosms with sediments
from an intermittent Mediterranean stream. In agreement with our initial hypothesis, our results showed how the NO3
−-N content of the sediment was enhanced during the first 10 days of sediment drying, whereas NH4
+-N was lost by 14 days post-drying. During the first 10 days, sediment desiccation seemed to stimulate the net N-mineralization
and net nitrification from sediments. Afterwards, the extractable NO3
−-N concentration sharply dropped, which may be attributed to lower ammonium-oxidation rates as ammonium and organic matter
are depleted, and to an increase in NO3
−-N consumption by microbial populations. Denitrification was inhibited, with a significant decrease as % water-filled pore
space lowered. We hypothesize that the sediment inorganic N content enhanced during sediment desiccation could be released
as part of the N pulse observed after sediment rewetting. However, the stream N availability after rewetting dried sediments
would differ depending on desiccation period duration. 相似文献
83.
84.
Simultaneous Detection of Aeromonas salmonicida, Flavobacterium psychrophilum, and Yersinia ruckeri, Three Major Fish Pathogens, by Multiplex PCR 总被引:2,自引:0,他引:2 下载免费PDF全文
A multiplex PCR assay based on the 16S rRNA genes was developed for the simultaneous detection of three major fish pathogens, Aeromonas salmonicida, Flavobacterium psychrophilum, and Yersinia ruckeri. The assay proved to be specific and as sensitive as each single PCR assay, with detection limits in the range of 6, 0.6, and 27 CFU for A. salmonicida, F. psychrophilum, and Y. ruckeri, respectively. The assay was useful for the detection of the bacteria in artificially infected fish as well as in fish farm outbreaks. Results revealed that this multiplex PCR system permits a specific, sensitive, reproducible, and rapid method for the routine laboratory diagnosis of infections produced by these three bacteria. 相似文献
85.
Panchón-Ruiz A Jornet-Carrillo V Sanchez del Campo F 《Journal of craniofacial genetics and developmental biology》2000,20(4):198-200
Moire topography was used to quantitatively determine the shape of the palatal vault in 57 Spanish patients with Down syndrome (DS) (38 males and 19 females; age range 18-36 years) and in 100 normal controls (N) (76 males and 24 females; age range 20-29 years). The topographic image for each palatal vault was analyzed and approximately 40 sets of coordinates (x, y, z) were recorded. Other parameters, including length, width and maximum height, were recorded from the palate vault images. No appreciable sexual dimorphism in palate dimensions was observed in DS subjects versus the situation in N subjects. Globally, the average N dimensions were significantly greater than those in the DS patients (P < 0.005). A special palatal morphology was found to be associated with DS, with different ratios for the three dimensions (mean factor 0.88 for length, 0.81 for width and 0.73 for height), versus the healthy palatal vaults. It is concluded that palatal morphology in DS fits an elliptic paraboloid. On the other hand, no lineal correlation was observed between height, width and length in the DS and N groups. The scatter plots of bivariate data exhibited a shapeless morphology. The lineal correlation coefficients ranged from 0.008 to 0.33 for the DS and N groups. 相似文献
86.
The partitioning of limited resources commonly explains how different species can coexist within the same ecological community. In this 2010 study, the diets of three coexisting freshwater fishes (Cape galaxias Galaxias zebratus, n = 27; Cape kurper Sandelia capensis, n = 60; Breede River redfin Pseudobarbus burchelli, n = 77) were characterised and compared in three headwater streams in South Africa's Cape Fold Ecoregion using gut contents and stable isotope analyses. These data were analysed to ascertain whether the three species exploit distinct trophic niches. Both approaches provided evidence that these species occupy different trophic niches, though with some overlap. However, dietary differences among sites were not consistent and were probably influenced by site-specific factors like resource availability. Pseudobarbus burchelli had a broader niche breadth at Tierkloof Stream than the other two species, but not at Waaihoek or Tierstel Streams. Our results also suggest that P. burchelli consumed a more omnivorous diet than do the other two species, whereas S. capensis occupied a higher trophic position than the other two species and consumed vertebrates. Our findings suggest that these species occupy non-equivalent feeding niches in Cape Fold Ecoregion headwater streams, and that diet partitioning might facilitate their coexistence in these systems. 相似文献
87.
Endotoxin-induced cytokine gene expression in vivo. III. IL-6 mRNA and serum protein expression and the in vivo hematologic effects of IL-6 总被引:19,自引:0,他引:19
T R Ulich K Z Guo D Remick J del Castillo S M Yin 《Journal of immunology (Baltimore, Md. : 1950)》1991,146(7):2316-2323
Endotoxin (LPS) at sublethal doses injected i.v. into rats was found to induce IL-6 mRNA expression peaking at 1 to 2 h in whole organ RNA preparations of the spleen, liver, lung, bowel, and kidney. IL-6 serum protein levels also peaked at 2 h. TNF and IL-1, generally considered to be among the most rapidly released cytokines, also induced IL-6 expression. IL-6 in turn inhibited TNF and IL-1 expression, suggesting that IL-6 may be part of a negative feedback mechanism in the cytokine cascade. Dexamethasone down-regulated and Corynebacterium parvum up-regulated IL-6 expression, although the possibility cannot be excluded that these immunomodulating factors may in part have exerted their effects indirectly via the up- and down-regulation of TNF and IL-1. IL-6 injected i.v. at a pathophysiologically relevant dose caused a peripheral neutrophilia and mild myeloproliferative effect in the bone marrow. 相似文献
88.
Bosch L Sanz ML Montilla A Alegría A Farré R del Castillo MD 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,860(1):69-77
Protein quality was assayed by simultaneous measurement of lysine (Lys), carboxymethyllysine (CML) and lysinoalanine (LAL). GC-FID analysis of N-tert-butyl dimethylsilyl (tBDMSi) derivatives of these amino acids was undertaken. tBDMSi derivates were separated on a CP-SIL 5CB commercially fused silica capillary column (25 m x 0.25 mm i.d., 0.25 microm film thickness) employing a thermal gradient programmed from 200 to 300 degrees C. The identity of tBDMSi derivatives of Lys, CML and LAL was established by GC-MS while FID detection was employed for quantification. Analytical parameters such as linearity (lysine 350-4200 microM, LAL 3-81 microM, CML 16-172 microM), precision (1-13% variation coefficients), accuracy (85-108% average recovery) and limits of detection (lysine 0.4 mg/100 g protein, LAL 5.0 mg/100 g protein, CML 3.4 mg/100 g protein) and quantification (lysine 1.4 mg/100g protein, LAL 15.2 mg/100 g protein, CML 11.2 mg/100 g protein) were determined for validation of the analytical approach. Model systems and real foods have been studied. Kinetic of CML formation from different food proteins (BSA, soy protein, casein and gluten) was performed employing model systems. Carboxymethylation rate depended on the source of protein. Maillard reaction progressed to advanced stages damaging the protein quality of stored infant foods, soy drinks, boiled eggs and dry powdered crepes. CML values ranged from 62 to 440 mg/100 g protein were measured. LAL was also formed during boiling eggs (21-68 mg/100g protein) indicating additional damage by crosslinking reaction. In agreement, lysine content was affected by both food processing and storage. 相似文献
89.
Ágnes Baross Allen D Delaney H Irene Li Tarun Nayar Stephane Flibotte Hong Qian Susanna Y Chan Jennifer Asano Adrian Ally Manqiu Cao Patricia Birch Mabel Brown-John Nicole Fernandes Anne Go Giulia Kennedy Sylvie Langlois Patrice Eydoux JM Friedman Marco A Marra 《BMC bioinformatics》2007,8(1):1-18