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841.
A study about the genesis of the inner lining which covers the mucous membrane of the chicken gizzard was made and histochemical test were employed to detect the presence of carbohydrate in the epithelial components of the mucous membrane. The histochemical treatment of the apical border of gizzard epithelium from the 5th, 7th, 9th, 12th, and 15th d of incubation revealed the absence of glycoprotein (with 1.2-glycol containing hexoses), sialic acid, and glycogen but weakly acidic sulphated mucosubstances were present. The same was observed in the medium 1/3 of the gizzard epithelium on 12th and 15th d. The upper 1/3 of the buddings, precursor of gizzard glands, on the 15th d, besides exhibiting the same histochemical characteristics of apical border, revealed, clearly visible, strongly sulphated mucosubstances. The histochemical reactions of the epithelium which covers the free surface and lines the pits from the 18th d of incubation and from the young chicken (0.5 h, 1 d, 3 d, 7 d, 3 weeks and 8 weeks) revealed the absence of glycoprotein (with 1.2-glycol containing hexoses), sialic acid, and glycogen, however, weakly acidic sulphated mucosubstances and strongly sulphated epithelial acidic mucin were present. On the 18th d, the glands presented a lumen and the accumulation of intraepithelial secretion displaced the upper part of the superficial epithelium, splitting, it.  相似文献   
842.
Adult hoverflies feed on pollen, nectar and honeydews. Thus, the implementation of floristically diverse resources in agroecosystems can enhance biological control of pests by increasing populations of these natural enemies. The objective of this work was to study the effect of seven species of Asteraceae (Andryala integrifolia L., Anthemis arvensis L., Calendula arvensis L., Carduus tenuiflorus Curtis, Chamaemelum nobile (L.) All., Coleostephus myconis (L.) Rchb.f. and Crepis vesicaria L.) on adult longevity and nutrient levels of Episyrphus balteatus (De Geer) (Diptera: Syrphidae). Crepis vesicaria and C. nobile gave the highest mean longevities while, for the other plant species, longevities were not significantly different from those in the water only treatment. In addition, all species tested resulted in significantly lower longevities than the positive control (glucose). In terms of nutrient levels, C. nobile generated high levels of total sugars and C. vesicaria high levels of lipids which suggests the consumption of flower resources. However, the majority of the plants tested would not allow hoverflies to complete their life cycle. Thus, further experimentation needs to be done before considering these plants for implementation in agroecosystems.  相似文献   
843.
The weight records from Simmental beef cattle were used in a genetic evaluation of growth with or without the inclusion of animals obtained by embryo transfer. A multi-trait model in which embryo transfer individuals were excluded (MTM1) contained 29,510 records from 10,659 animals, while another model without exclusion of these animals (MTM2) contained 62,895 weight records from 23,160 animals. The weight records were adjusted for ages of 100, 205, 365, 450, 550 and 730 days. The (co)variance components and genetic parameters were estimated by the restricted maximum likelihood method. The (co)variance components were similar in both models, except for maternal permanent environment variance. Direct heritabilities (h2d) in MTM1 were 0.04, 0.11, 0.20, 0.27, 0.31 and 0.42, while in MTM2 they were 0.11, 0.11, 0.17, 0.21, 0.22 and 0.26 for 100, 205, 365, 450, 550 and 730 days of age, respectively. Estimates of h2d in MTM1 were higher than in MTM2 for the weight at 365 days of age. Genetic correlations between weights in both models ranged from moderate to high, suggesting that these traits may be determined mainly by the same genes. Animals from embryo transfer may be included in the genetic evaluation of Simmental beef cattle in Brazil; this inclusion may provide potential gains in accuracy and genetic gains by reducing the interval between generations.  相似文献   
844.
The sialic acid-binding immunoglobulin-type lectin Siglec-15 is a promising target for cancer immunotherapy in several tumor types. The present study aimed to investigate Siglec-15 expression in gastric cancer (GC) patient tissues and to evaluate its clinical value. Siglec-15 expression was evaluated by immunohistochemistry in 71 patients. Siglec-15 staining was observed in tumor cells of 53 (74.64%) patients, with significant association with histologic classification and angiolymphatic invasion (p<0.05). Immunohistochemistry analysis also detected Siglec-15 in tumor-associated stroma cells (macrophages/myeloid cells). There was no significant association with outcome parameters. Siglec-15 expression in well differentiated histological GC tissues and in the tumor microenvironment are potential targets to be further investigated as a novel prognostic factor for GC.Key words: Siglec, sialic acid, immunohistochemistry, clinical-pathological analyses  相似文献   
845.
846.
847.
Several studies point to the increased risk of reactivation of latent tuberculosis infection (LTBI) in patients with chronic inflammatory arthritis (CIAs) after using tumour necrosis factor (TNF)α blockers. To study the incidence of active mycobacterial infections (aMI) in patients starting TNF α blockers, 262 patients were included in this study: 109 with rheumatoid arthritis (RA), 93 with ankylosing spondylitis (AS), 44 with juvenile idiopathic arthritis (JIA) and 16 with psoriatic arthritis (PsA). All patients had indication for anti-TNF α therapy. Epidemiologic and clinical data were evaluated and a simple X-ray and tuberculin skin test (TST) were performed. The control group included 215 healthy individuals. The follow-up was 48 months to identify cases of aMI. TST positivity was higher in patients with AS (37.6%) than in RA (12.8%), PsA (18.8%) and JIA (6.8%) (p < 0.001). In the control group, TST positivity was 32.7%. Nine (3.43%) patients were diagnosed with aMI. The overall incidence rate of aMI was 86.93/100,000 person-years [95% confidence interval (CI) 23.6-217.9] for patients and 35.79/100,000 person-years (95% CI 12.4-69.6) for control group (p < 0.001). All patients who developed aMI had no evidence of LTBI at the baseline evaluation. Patients with CIA starting TNF α blockers and no evidence of LTBI at baseline, particularly with nonreactive TST, may have higher risk of aMI.  相似文献   
848.
IntroductionThe clinical outcome to Leishmania-infection is determined by the individual adaptive immune T helper cell responses and their interactions with parasitized host cells. An early development of a proinflammatory immune response (Th1 response) is necessary for Leishmania-infection resolution. The Toll-interacting protein (TOLLIP) regulates human Toll-like receptors signaling pathways by down regulating the proinflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) and inducing the ant-inflammatory cytokine interleukin-10 (IL-10). Polymorphisms in the TOLLIP gene are associated with infectious diseases.ResultsThe G and T alleles of the rs5743899 and rs3750920 were more common in patients with CL than in healthy individuals (P = 2.6 x10-8 ; odds ratio [OR], 1.7 [ 95% confidence interval (CI) 1.4–2.0] and P = 1.9 x10-8 ; OR, 1.6 [95% CI 1.4–1.9] respectively). The r2 and D’ linkage disequilibrium between the two polymorphisms are 0.05 and 0.473 with a confidence bounds of 0.37 to 0.57 respectively.ConclusionThe two polymorphisms are independently associated with an increased risk of developing CL.  相似文献   
849.
Pempheris gasparinii sp. n. is described from five specimens, 59.1–68.0 mm in standard length. It is only known to occur in the shallow reefs of Trindade Island, 1200 km east of the Brazilian coast, in the southwestern Atlantic. Pempheris gasparinii is the third recognized species of Pempheris in the Atlantic Ocean. This new species is morphologically similar to its close relative, Pempheris poeyi, differing by the number of lateral-line scales (51–54 in Pempheris gasparinii vs. 47–49 in Pempheris poeyi), scales below lateral line (10–11 vs. 9), circumpeduncular scales (11–12 vs. 13), head and caudal peduncle lengths (2.7–3.3 vs 3.5–4.0 in head length). Moreover, Pempheris gasparinii shows a 4% genetic divergence from Pempheris poeyi at the cytochrome oxidase I locus (COI), consistent with a lineage split at the beginning of the Pleistocene. This new species represents the 12th endemic fish species from Trindade Island.  相似文献   
850.
The number of fish habitat improvement schemes has greatly increased in response to the widespread degradation of aquatic ecosystems. However, many of these enhancement projects often fail to create expected habitat conditions, because they are rarely planned and executed with inputs from the species’ habitat requirements throughout their life histories, and it is frequently assumed that the implementation of a specific instream structure for habitat improvement will always benefit all species present. Using a 2D hydraulic model, the present study evaluates the potential habitat improvement for two critically endangered fish species—the Southwestern arched-mouth nase Iberochondrostoma almacai and the Arade chub Squalius aradensis—resulting from simulating the introduction of different instream structures (islands, lateral bays, and deflectors) in a modified Mediterranean river reach. The introduction of islands in the river channel was found to be the best improvement measure for YOY and juvenile nase and chub, as shown by increases in the mean annual Weighted Usable Area (WUA) of more than 100 and 50%, respectively, compared to the present conditions. On the other hand, the simulation with current deflectors proved to be the worst scenario, particularly for nase, with mean annual WUA decreasing by 3.6, 17.8 and 22.7% for YOY, juveniles and adults, respectively. The findings of this study point to the need to account for different species life-history stages when modelling the implementation of instream structures for habitat improvement and also provide a sound basis for future conservation-related studies conducted in Mediterranean rivers that harbour other threatened “sister” species.  相似文献   
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