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71.
Innate immune signals mediated by Toll-like receptors (TLRs) have been thought to contribute considerably to the antibody-enhancing effects of vaccine adjuvants. However, we report here that mice deficient in the critical signaling components for TLR mount robust antibody responses to T cell-dependent antigen given in four typical adjuvants: alum, Freund's complete adjuvant, Freund's incomplete adjuvant, and monophosphoryl-lipid A/trehalose dicorynomycolate adjuvant. We conclude that TLR signaling does not account for the action of classical adjuvants and does not fully explain the action of a strong adjuvant containing a TLR ligand. This may have important implications in the use and development of vaccine adjuvants.  相似文献   
72.
Three recombinant inbred line populations from the crosses RL6071/Thatcher, RL6071/RL6058 (Thatcher Lr34), and Thatcher/RL6058, were used to study the genetics of stem rust resistance in Thatcher and TcLr34. Segregation of stem rust response in each population was used to determine the number of genes conferring resistance, as well as the effect of the leaf rust resistance gene Lr34 on stem rust resistance. The relationship between resistance in seedling and adult plants was also examined, and an attempt was made to identify microsatellite markers linked to genes that were effective in adult plants. In field plot tests at least three additive resistance genes segregated in the RL6071/RL6058 population, whereas two resistance genes segregated in the RL6071/Thatcher population. The presence of the gene Lr34 permitted the expression of additional stem rust resistance in Thatcher-derived lines both at the seedling and adult plant stages. Seedling resistance to races TPMK and RKQQ was significantly associated with resistance in adult plants, whereas seedling resistance to races QCCD and QCCB may have made a minor contribution. The seedling resistance genes Sr16 and Sr12 may have contributed to resistance in adult plants. A molecular marker linked to resistance in adult plants was identified on chromosome 2BL.  相似文献   
73.
Phytochemical diversity with respect to a range of polar (including amino acids, organic acids, sugars, and sugar alcohols) and nonpolar (including fatty acids, alkanols, and sterols) metabolites was examined within tubers from a total of 29 genetically diverse potato cultivars and Chilean landraces using a metabolomics approach by gas chromatography-mass spectrometry. From principal component analysis of the polar and nonpolar metabolite data there was insufficient variation to differentiate the majority of cultivars and landraces. Analysis of all polar metabolite profiles revealed separation of two cultivars (Glenna and Morag) from the other cultivars and landraces and a separate cluster of one landrace line, largely due to higher levels of sugars. Pentland Javelin was distinct in containing high levels of many amino acids. The two Solanum tuberosum group phureja cultivars (Inca Sun and Mayan Gold) were not particularly similar and were not separated from the S. tuberosum group tuberosum cultivars. Analysis of the nonpolar metabolite data revealed partial separation of two landrace lines and, on the basis of some minor fatty acids, Mayan Gold was distinct. The differences in metabolite profiles are considered in terms of the taxonomy and breeding history of the cultivars and possible influences from other factors such as developmental stage of the tuber. With a view to exploring biosynthetic links between metabolites, a pairwise correlation analysis was performed on all metabolites. The significance of high correlations between many amino acids and between several nonpolar metabolites is discussed.  相似文献   
74.
At the present time, there is little information concerning the effect of transport on the physiology of scallops. Therefore, the overall objective of this study was to use the adenylic energetic charge (AEC) as an indicator of stress in scallops. Three transport trials were carried out: dry transport in polystyrene boxes containing seaweed and transport by vivier lorry at various densities. Post-transport scallop mortality was low for all trials, but the AEC results showed that scallop stress was reduced when animals were transported by vivier truck compared with dry transport. AEC levels in scallops remained high after 24.75 h of vivier transport in trial 2 (0.54–0.69) and after 17 h of vivier transport in trial 3 (0.79–0.82), whereas after 12 h of dry transport in trial 1, AEC levels in the striated muscle had decreased to 0.42. Ammonia concentration increased throughout the trials but did not appear to affect scallop survival in the short term. In general, the results indicate that greater survival can be achieved over longer distances (greater than 17 h) and at higher densities by vivier truck. However, better stability of holding units within tanks and a method to regulate ammonia and pH levels are needed if greater densities are used.  相似文献   
75.
OBJECTIVE: To determine the prevalence of various clinical signs in dogs with brain tumors. DESIGN: Retrospective study. ANIMALS: 97 dogs with brain tumors. PROCEDURE: Medical records were reviewed for signalment, tumor type and location, and clinical signs. RESULTS: 33 breeds were represented; Golden Retrievers were most commonly affected. Most dogs were older (median age, 9 years); 95% of dogs were > or = 5 years old. Seventy-six percent of dogs had tumors in the supratentorial region. Seizures were the most common clinical sign at initial examination, with lower prevalence for circling, ataxia, and head tilt. Meningioma was the most common tumor. CONCLUSIONS AND CLINICAL RELEVANCE: Brain tumors develop most often in dogs > or = 5 years old and are uncommon in dogs < 5 years old. Seizures are a common clinical sign, and a brain tumor should be considered in dogs that have their first seizure after they are 4 years old.  相似文献   
76.
International Aquatic Research - The effects of temperature and salinity on the survival and development of larval Metapenaeus dalli were investigated in two experiments. First, the effects of four...  相似文献   
77.
The bitterness of racemic praziquantel (Rac‐PZQ) constrains its use as an in‐feed treatment against monogenean flukes in finfish aquaculture. Evidence exists in mammals that the R‐(?) enantiomer of PZQ is less bitter than the S‐(+) enantiomer. If fish exhibit this same response, then the recently described techniques for the large‐scale resolution of R‐(?)‐PZQ from Rac‐PZQ could facilitate the wide‐spread application of this effective anthelmintic compound via feed. The hypothesis that yellowtail kingfish Seriola lalandi would find R‐(?)‐PZQ more palatable than Rac‐PZQ and S‐(+)‐PZQ was tested in four trials. During the first three trials, the palatability of diets top‐coated with 10 g kg?1 of Rac‐PZQ or its two enantioseparated isomers were compared in small (85–160 g) and large (1.2 kg) yellowtail kingfish. A fourth trial compared the palatability of R‐(?)‐PZQ and Rac‐PZQ at dietary inclusion levels of 2.5, 5.0 and 10.0 g kg?1 in small yellowtail kingfish (170 g). Ingestion data showed that R‐(?)‐PZQ to be no more palatable than either Rac‐PZQ or S‐(+)‐PZQ to yellowtail kingfish, regardless of size. Indeed, evidence suggested that the S‐(+)‐PZQ to be slightly more palatable than both R‐(?)‐PZQ and Rac‐PZQ. From these data, we hypothesize that the strong smell of R‐(?)‐PZQ (which was not present in S‐(+)‐PZQ) is an equally important determinant to palatability as taste in yellowtail kingfish. Results demonstrate that dietary inclusion level is a more important determinant to palatability than PZQ chirality; however, administration of R‐(?)‐PZQ may still be advantageous if it is demonstrated to be the only enantiomer efficacious against monogeneans.  相似文献   
78.
Rice blast is caused by the fungus Magnaporthe grisea, which elaborates specialized infection cells called appressoria to penetrate the tough outer cuticle of the rice plant Oryza sativa. We found that the formation of an appressorium required, sequentially, the completion of mitosis, nuclear migration, and death of the conidium (fungal spore) from which the infection originated. Genetic intervention during mitosis prevented both appressorium development and conidium death. Impairment of autophagy, by the targeted mutation of the MgATG8 gene, arrested conidial cell death but rendered the fungus nonpathogenic. Thus, the initiation of rice blast requires autophagic cell death of the conidium.  相似文献   
79.
BackgroundAortic and aortoiliac thrombosis in dogs causes disease and death.ObjectiveTo describe the procedure and outcomes for stenting the caudal aorta and aortoiliac trifurcation.AnimalsSeven client‐owned dogs that underwent aortic/aortoiliac stenting for treatment of thrombosis.MethodsRetrospective multi‐center investigation. Medical records were reviewed for dogs that underwent stenting of the aorta or aortoiliac trifurcation between 2008 and 2020. Information collected included history, signalment, clinicopathologic data, diagnostic imaging, procedure reports, and outcomes.ResultsSeven dogs with an occlusive thrombus located at or near the aortic trifurcation were included. Four of 7 dogs were non‐ambulatory. Hind limbs were paretic in 5 dogs, paralyzed in 1 dog, and claudication alone was noted in 1 dog. Five of the 7 dogs had protein‐losing nephropathy (PLN). Of 5 dogs with PLN, 1 had protein‐losing enteropathy (PLE) and controlled hypothyroidism and 1 had caudal aortic chondrosarcoma. Two dogs had no identified underlying disease. Angiography was performed before catheter directed thrombolysis and stent placement. No deaths occurred during the procedure. Postoperative complications included pain (4/7), bruising and edema (3/7), bruising only (1/7), and edema only (1/7). Median survival time (MST) of the 7 dogs was 264 days (range, 1‐1053 days). Five of 7 dogs were ambulatory within 2 days of stenting and survived to discharge with a MST of 425 days (range, 208‐1053 days).Conclusions and Clinical ImportanceStenting of the aorta and aortoiliac trifurcation can provide an apparently safe and effective treatment with rapid return to ambulation for some dogs with aortic thrombosis.  相似文献   
80.
Agricultural vaccine trials are costly, and it is important that they should provide the maximum amount of information. The traditional probit model often fails to provide a reliable estimate of median protective dilution. The complementary loglog transformation is to be preferred because it provides a probabilistic basis for fixing one of the parameters, thereby increasing the precision of estimation.  相似文献   
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