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1.
Change of porcine circovirus 2 (PCV2) target cells during development from fetal to postnatal life in pigs was examined. PCV2 inoculation was performed in fetuses in utero at either 57, 75 or 92 gestational days and in piglets at 1 day of age. Twenty-one days after virus inoculation, PCV2-infected cells in the heart, lungs, liver, spleen and inguinal lymph nodes were localized and immuno-phenotyped by double-immunofluorescence labeling using different cell markers and PCV2-antibodies. During fetal life, viral antigens were detected in cardiomyocytes, hepatocytes and macrophages and infected cell numbers decreased with increasing fetal age at inoculation. The heart contained the highest number of infected cells and cardiomyocytes were the main target cell. Postnatally, macrophages were the only target cell type in different organs and infected cell numbers were similar to those of fetuses inoculated at 92 days of gestation. One piglet showed exceptionally high number of infected cells in different organs with values 13-513-fold higher compared to littermates. In this piglet, the majority of infected cells in lymphoid tissues could not be typed. This study reveals that PCV2 target cells change from cardiomyocytes, hepatocytes and macrophages during fetal life to only macrophages postnatally.  相似文献   
2.
A 10-year-old male Drahthaar dog with unilateral cryptorchidism was examined because of feminisation and myelotoxicity. Radiography and ultrasonography revealed an abdominal mass which was surgically removed. The mass was identified as a Sertoli cell tumour on histological examination. Findings on bone marrow examination were compatible with aplasia due to the oestrogens secreted by the tumoral cells. Treatment with fluids, antibiotics, whole blood transfusions, corticosteroids and lithium carbonate was unsuccessful. Survival time was 22 days after surgery.  相似文献   
3.
  • 1. Nubbins from 12 coral species were transplanted onto dead giant clam shells at three sites in a lagoon near Bolinao, north‐western Philippines. Transplants were attached using three types of adhesives: cyanoacrylate glue (SG), epoxy putty (EP) and marine epoxy (ME) and were monitored over five months for detachment, in situ mortality and natural self‐attachment by tissue growth.
  • 2. Corals attached with SG showed a significantly higher rate of detachment (logrank test) than those attached with either EP or ME (P<0.001 in each case). Also, those attached with EP showed a higher rate of detachment than corals attached with ME (logrank=6.46, P<0.05).
  • 3. ANOVA (P>0.05) and survival analysis (logrank=2.85, P>0.05) showed no among‐adhesives differences in in situ mortality. Among the species used, Porites cylindrica, Pavona frondifera, Heliopora coerulea and Porites rus had the highest survivorship with 82%, 80%, 76% and 73%, respectively, of nubbins alive at the end of the experiment and also displayed the highest cumulative rates of self‐attachment. Species with the lowest survival rates included Acropora muricata and four pocilloporids.
  • 4. Although there was no significant difference in the number of self‐attaching transplants among the adhesives, corals transplanted using ME and EP self‐attached earlier than those transplanted using SG (logrank=11.19, P<0.01).
  • 5. Results from this study highlight the importance of selecting the appropriate means of attaching corals to substrates and carefully considering species‐specific traits of candidate corals for transplantation.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
4.
5.
Complexes of β-cyclodextrin (β-CD) and caffeine (Caf) with biophenols present in olive and olive oil (tyrosol, hydroxytyrosol, homovanillic acid, 3,4-dihydroxyphenylacetic acid, and protocatechuic acid) were investigated by NMR spectroscopy and thermodynamical-molecular dynamic studies to verify the formation of supermolecular aggregates. The obtained results indicated that the investigated biophenols form inclusion complexes with β-CD in a molar ratio of 1:1 in aqueous solution having binding constant values from 10- to 40-fold bigger than those of the corresponding complexes with Caf. Then, β-CD preferentially encloses the biophenol molecule, decreasing its bitter taste and, at the same time, preserving it against chemical and physical decomposition reactions that occur during storage.  相似文献   
6.
Skin fibroblasts from a patient with Fabry's disease showed deficient activity of alpha-galactosidase. Fibroblasts from his mother and sister had two distinct clonal populations, one with enzymatic activity and the other enzyme deficient. This provides evidence of genetic inactivation at the alpha-galactosidase locus and makes possible the detection of carriers of Fabry's disease even when the enzymatic activity in their leukocytes and uncloned fibroblasts is within the range of controls.  相似文献   
7.
Water, Air, & Soil Pollution - From May 1998 to May 1999, the clams Ruditapes decussatus were collected each month at three stations of the Bizerta lagoon. This paper represents a synthesis...  相似文献   
8.
Hybrid rice (Oryza sativa L.) has been proven to be effective in increasing yield potential, but lodging often limits its yield in high-yielding environments. This study was conducted to determine genotypic variation in lodging resistance and lodging-related morphological traits among hybrid and non-hybrid check varieties, and to identify the key morphological traits associated with lodging resistance. Lodging behavior of 16 rice genotypes, including 12 hybrids and four inbreds, was studied at the International Rice Research Institute farm during the 2004 wet season (WS) and 2005 dry season (DS). Grain yield and visual score of lodging were determined at maturity. Lodging-related morphological traits were measured at 30 days after flowering. Large genotypic differences in lodging-related morphological traits were observed. Among these traits, dry weight per unit length, breaking resistance, and lodging index (bending moment/breaking resistance × 100) of lower internodes were significantly correlated with visual score of lodging. Several hybrids demonstrated high lodging resistance although their average plant height was over 120 cm. The lodging-related morphological traits and visual score of lodging in these hybrids were comparable with those of the non-hybrid check varieties with strong lodging resistance. These results suggest that increases in dry weight per unit length and breaking resistance of lower internodes are primary targets for reducing lodging index, thus improving overall lodging resistance of hybrid rice in a breeding program.  相似文献   
9.
Limonoid glucosides (primarily limonin 17-beta-D-glucopyranoside, LG) were extracted from grapefruit molasses by supercritical fluid extraction using a supercritical carbon dioxide-ethanol (SC CO(2)-ethanol) system. Extraction conditions to maximize the yield of LG were determined by varying pressure, temperature, ethanol concentration, and extraction time. The highest yield of LG at 0.61 mg/g molasses was obtained at a pressure 48.3 MPa, a temperature of 50 degrees C, 10% ethanol (X(Eth) = 0.1), and 40 min of extraction time at a flow rate of 5.0 L/min. The results demonstrated that SC CO(2) extraction of limonoid glucosides from grapefruit molasses has practical significance for commercial production.  相似文献   
10.
This publication reviews some pathogenetic features of the transplacental infection with porcine viruses in sows. Viremia either with virus freely circulating or associated to peripheral blood mononuclear cells (PBMC) is an essential part of such pathogenesis. Virus replication occurs either in fetal tissues only or both in fetal and maternal tissues and the outcome may be different.Since porcine circovirus 2 (PCV2) has been associated with reproductive failure in sows, the question was asked what type of viremia PCV2 causes and what the effect of PCV2 is on the pregnant uterus. Seronegative gilts were oronasally inoculated and plasma and PBMC were monitored for infectious virus and for quantity of viral DNA copies. Infectious virus was found in plasma only at 21 days post-inoculation (DPI). Virus associated to PBMC was detected between 14 and 49 DPI. Viral DNA was found in plasma between 14 and 49 DPI and associated to PBMC between 7 and 63 DPI (end of experiment). Direct intra-fetal inoculation at 57, 75 and 92 days of gestation and collection of fetuses 21 days later showed that the virus replicates highly in fetal tissues, particularly in the heart. Fetal death occurred in the 57 days sows while virus and antibodies were observed in the 75- and 92-day inoculated sows. Inoculation at 57 and 75 days of gestation and collection of the piglets at the end of pregnancy showed that intrauterine spread had occurred to fetuses adjacent to the inoculated ones and that fetal death occurred also in the presence of antibodies. The pregnancy was not interrupted.This study shows that PCV2 causes viremia which is largely cell-associated and that virus replication in fetuses causes fetal death with mummification. Whether such transplacental infection occurs in the immune sow population is questionable.  相似文献   
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