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61.
Atypical porcine pestivirus (APPV) is a cause of congenital tremors (CTs) in piglets and has been found in swine populations around the globe. Although systemic distribution of the virus has been reported, there is limited information regarding viral localization at the cellular level and distribution at the tissue level. We collected multiple tissues from 2-d-old piglets (n = 36) born to sows inoculated at 45 or 62 d of gestation with APPV via 3 simultaneous routes: intravenous, intranasal, and directly in amniotic vesicles. In addition, 2 boars from APPV-inoculated sows with CT were raised and euthanized when 11 mo old. In situ hybridization performed on tissue samples from piglets demonstrated a broad and systemic distribution of viral RNA including endothelial cells, fibroblasts, and smooth muscle. Labeling in tissues was more pronounced in piglet tissues compared to boars, with the notable exception of diffuse labeling of the cerebellum in boars. Presence of APPV in boar tissues well after resolution of clinical signs suggests persistence of APPV similar to other pestiviruses.  相似文献   
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Total extract from the fruit of Szechuan pepper (Zanthoxylum piperitum DC), the volatile components of the extract and a non‐volatile fraction containing alkylamides (NVA fraction) are feeding deterrents for rats. The present study investigated the effectiveness of these natural repellents in prairie voles (Microtus ochrogaster Wagner). Two‐choice feeding trials were conducted during which food‐deprived voles were offered choices between oat‐bran wafers. In Experiment 1, 10 voles were given three sets of feeding trials, each 2 h long. Baseline consumption was established during the first set of two trials by offering a choice between two oat‐bran wafers dipped in ethanol, the control solvent. During the second set of two trials the voles were given a choice between an oat‐bran wafer dipped in ethanol and a wafer dipped in Zanthoxylum extract. During the third set the voles were given a choice between a wafer served on top of a screened dish containing a sample of ethanol and a wafer served on top of a dish containing a sample of extract. In this manner the voles were exposed to volatile compounds emanating from the extract but could not contact it. Wafers dipped in extract were almost completely avoided. The volatile components of extract also significantly reduced food intake. In Experiment 2, habituation to the volatile constituents of extract was examined in 16 Zanthoxylum‐naïve voles. Baseline consumption was established by offering two wafers served on top of screened dishes containing ethanol. This was followed by twelve tests during which a choice between a wafer served above a sample of ethanol and a wafer served above a sample of extract was given. The voles failed to habituate to the volatile components of extract, consistently consuming less of the wafers served above extract. In Experiment 3 a dose‐response curve to Zanthoxylum extract was established, using 12 stimulus‐naïve voles. After baseline consumption was established, the animals were given two tests each, presenting a choice between a control wafer and a wafer dipped in a dilution of extract (0.001–100 g liter?1). Only concentrations of 10 and 100 g liter?1 reduced food intake. In Experiment 4 the effects of the non‐volatile fraction of extract were compared to those of whole extract. Vegetable oil was used as solvent. Eight stimulus‐naïve voles were given two tests with a choice between an oil‐dipped and an extract‐dipped wafer. A second group of eight voles received two tests with a choice between an oil‐dipped and NVA‐dipped wafer. Extract‐dipped wafers were avoided, but the NVA fraction had no effect on food consumption. Copyright © 2004 Society of Chemical Industry  相似文献   
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Fifteen captive female African hedgehogs (Atelerix albiventris), 3- to 5-yr-old, were diagnosed with proliferative uterine lesions (n = 28). Lesions were associated with vaginal bleeding in all cases, hematuria in 11 of 13 cases, and weight loss in 7 of 12 cases. Lesions were multiple in eight cases and single in seven cases. The lesions identified were 13 adenosarcomas, 7 endometrial stromal sarcomas, 6 endometrial polyps, 1 adenoleiomyosarcoma, and 1 adenoleiomyoma. In one animal with adenosarcoma, peritoneal seeding was detected at the time of hysterectomy. Mean survival time was 303 days (n = 10). Ovariohysterectomy allows prolonged survival of hedgehogs with uterine tumors.  相似文献   
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Plant Foods for Human Nutrition - Flaxseed meal, a byproduct of flaxseed oil extraction, was treated as low-value agrowaste for a long time despite its high protein content. Flaxseed meal has...  相似文献   
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Summary It is shown in biometrical studies performed for two years and concerning the statistical diversity of fruitshape within one plant having two fruits that fruitshape is inherited as a reaction norm, the mother fruit being without influence on the progeny. The shape of the first fruit is extremely modifiable. Realization of the various fruit shapes is influenced at the end of the vegetative period by the position of the fruit on the plant, by weather, by infection and other environmental conditions. Experiments were done with someCucurbita pepo convar.patissonina Greb. inbred lines of the same origin.
PEP 1, , . , - , ( ) — , , . , ( ) , . ( ) . ( ) , , , . . , ; (Grebenikov 1960).
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Manytoolssuchasboningknives,meatmincingmachinecrossknivesandgrates,cutterknivesthatarewidelyusednowadaysinmeatprocessingindustryhavelowsafetyindex.Inthisconnectionitbecamenecessarytoimprovecuttingtoolsbyincreasingtheirsafety.1 Meatmincingmachinecrosskn…  相似文献   
70.
Lifelong blood cell production is dependent on rare hematopoietic stem cells (HSCs) to perpetually replenish mature cells via a series of lineage-restricted intermediates. Investigating the molecular state of HSCs is contingent on the ability to purify HSCs away from transiently engrafting cells. We demonstrated that human HSCs remain infrequent, using current purification strategies based on Thy1 (CD90) expression. By tracking the expression of several adhesion molecules in HSC-enriched subsets, we revealed CD49f as a specific HSC marker. Single CD49f(+) cells were highly efficient in generating long-term multilineage grafts, and the loss of CD49f expression identified transiently engrafting multipotent progenitors (MPPs). The demarcation of human HSCs and MPPs will enable the investigation of the molecular determinants of HSCs, with a goal of developing stem cell-based therapeutics.  相似文献   
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