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71.
Ultraviolet laser microprobe analyses of a calcium-aluminum-rich inclusion (CAI) from the Allende meteorite suggest that a line with a slope of exactly 1.00 on a plot of delta17O against delta18O represents the primitive oxygen isotope reservoir of the early solar nebula. Most meteorites are enriched in 17O and 18O relative to this line, and their oxygen isotope ratios can be explained by mass fractionation or isotope exchange initiating from the primitive reservoir. These data establish a link between the oxygen isotopic composition of the abundant ordinary chondrites and the primitive 16O-rich component of CAIs.  相似文献   
72.
A feeding trial was conducted to evaluate the effects of moderate dietary concentrations of deoxynivalenol (DON) during a 21-day feeding experiment on the performance of broilers. Fifteen 1-day-old broiler chicks were randomly divided into two groups. The control group was fed non-contaminated diet. Another group of broilers was fed a diet naturally contaminated with 5 mg DON/kg diet. Deoxynivalenol had no effect (p > 0.05) on feed consumption, feed conversion, body-weight gain, live body weight or mortality. The absolute and relative weight of the organs (gizzard, pancreas, heart, spleen, colon and caecum) were not altered by the dietary inclusion of DON contaminated grain. However, both the absolute and relative weight of small intestine was decreased (p < 0.01) in DON fed broilers compared to the controls. No gross lesions were detected in any of the organs of birds fed contaminated wheat during the feeding trial. The microscopic examination revealed that, the height and the width of villi in duodenum decreased (p < 0.05) in birds fed DON contaminated wheat compared to controls. On the other hand the height and the width of jejunum villi were not affected (p > 0.05). This study indicates that feeding DON for 21 days to broiler chickens at a concentration of up to 5 mg/kg of diet influenced the weight of the small intestine as well as intestinal histology, especially the duodenum, as evidenced by shorter and thinner villi. In conclusion, diets with DON contamination below levels that induce negative impact on health and performance could affect small intestinal morphology in broilers.  相似文献   
73.
Extract

Lytic lesions with microscopic features similar to those of vaccine-site sarcomas were diagnosed in the distal femur of two young neutered male cats, one a 20-month-old Birman and the other an 18-month-old domestic short-hair (DSH). Radiographically, there was extensive destruction of trabecular and cortical bone in the metaphysis and/or epiphysis of the distal femur. The DSH cat also had angular deformity of the distal femur due to asymmetrical involvement of the physis. Histologically, the lesions in both cats consisted of dense, interwoven bundles of fibrous connective tissue, amongst which there were variable numbers of plump malignant mesenchymal cells, often with very large, hyperchromatic nuclei and irregularly shaped nucleoli. Several focal aggregates of small lymphocytes were present in both tumours. Although neither cat had apparently been vaccinated in the hindlimb it is possible that the tumours had been triggered by injection of some other irritant material.  相似文献   
74.
Uterine tissue from pregnant bitches was investigated by qualitative RT-PCR for the gene expression of local factors potentially important for the implantation of canine embryos. For this purpose, 10 bitches identified as being at the time of implantation or early placentation by means of ultrasonography before ovariohysterectomy (days 20–35, n = 10) provided tissues for comparison to tissue collected in a previous study and identified as early pregnant (n = 10) or non-pregnant (n = 4) by embryo flushing after ovariohysterectomy (days 10–12 after mating; Schäfer-Somi et al. 2008 ). Uterine tissue was excised from the middle of the left horn from early pregnant and non-pregnant animals, including from interplacental and placentation sites. The following genes were investigated: CD-4, -8; cyclooxygenase (COX)-1, -2; granulocyte macrophage-colony stimulating factor (GM-CSF); hepatocyte growth factor (HGF); insulin-like growth factor (IGF)-1, -2; transforming growth factor (TGF) and tumour necrosis factor (TNF)-α; interferon (IFN)-γ; interleukin (IL)-1β, -2, -4, -6, -8, -10, -12; leukaemia inhibitory factor (LIF) and leptin. Gene expression for CD-8, COX-1, TGF-β, HGF, IGF-1, IL-2, -4,-10, IFN-γ and LIF were detected in the pre-implantation uterus, and all except IL-2 and -10 were still detectable during the implantation and placentation stage. During implantation, mRNA for IGF-2 and GM-CSF were additionally detected. The dioestrous uterus differed from the pregnant uterus because of the absence of CD-8, IL-4 and IFN-γ and the expression of CD-4, TNF-α and IL-6. The results suggest that IL-4, IFN-γ, CD-8, GM-CSF and IGF-2 are regulated in a pregnancy-specific manner and that GM-CSF and IGF-2 probably have growth supporting and immune modulating functions during implantation of the canine embryo.  相似文献   
75.
Methods to discriminate plant oils facilitate the detection of either deliberate or accidental adulteration. To this direction, the variability in length among plant species of the chloroplast trnL intron was exploited for the authentication of edible and cosmetic plant oils, with an extra emphasis on olive oil. The methodology was based on the combinatorial use of a PCR assay with a capillary electrophoresis system such as the lab-on-a-chip technology. Application of the assay on DNA extracted from different oil producing plant species, including olive oil and sesame oil, indicated the ability of the trnL intron to be used as an analytical target. Furthermore, this assay could be used for the detection of adulteration of olive oil with various other plant oils, with the exception of avocado and sesame oil.  相似文献   
76.
This study compared endometrial cytology vis‐a‐vis uterine fluid cytology for assessment of uterine health in clinically normal and subclinical endometritis (SE)‐affected buffaloes. Uterine fluid samples and endometrial samples were collected from the buffaloes (n = 38) at oestrus using blue sheath and cytobrush, respectively. The smears were stained with Field stain for 3 minutes, and a minimum of 400 cells were counted in each smear for determination of the percentage of polymorphonuclear (PMN) leucocyte. The incidence of subclinical endometritis, based on the cytobrush cytology, was 23.08%. The correlation between cytobrush cytology with uterine fluid cytology was positive and significant (r = .37; p = .02). The ratio of PMN leucocyte in cytobrush cytology to uterine fluid cytology was 1:2.4. ROC analysis revealed that the threshold value of 6.16% PMN leucocyte in uterine fluid cytology showed a diagnostic sensitivity and specificity of 100% in differentiating normal from SE‐affected buffaloes. In conclusion, collection of uterine fluid was easier compared to collection of endometrial samples using cytobrush and the percentage of PMN leucocyte in uterine fluid cytology can be used as a tool for diagnosis of subclinical endometritis in buffaloes.  相似文献   
77.
78.
The digestive tract is a target for the Fusarium toxin deoxynivalenol (DON), a major cereal grain contaminant of animal and public health concern. Toxic effects of DON range from diarrhoea, vomiting and gastrointestinal inflammation to necrosis of several tissues. Following ingestion of contaminated food or feed, intestinal epithelial cells are exposed to a high concentration of ingested DON, potentially affecting intestinal functions. Pigs are considered to be the species most sensitive to DON toxicity. However, only few studies directly evaluated DON effects on porcine intestinal epithelial cells. Therefore, we used the porcine intestinal cell line (IPEC-J2) to assess short-term effects of DON on functional characteristics of the intestinal epithelial cells. The cytotoxic effect of DON on IPEC-J2 cells was evaluated by measuring the count of living cells and the activity of lactate dehydrogenase (LDH) released in the culture media at a DON concentration range from 0, 0.5, 2.5 and 10 μm. We demonstrated that DON at concentrations of 2.5 and 10 μm decreased significantly (p < 0.001) the cell count in a dose-dependent manner. At a concentration of 10 μm, DON caused cell damage, including rounding of cells, autolysis and cell loss from the monolayer. The mycotoxin, DON, increased LDH release into the culture medium compared with the control value. The alterations of LDH showed a good agreement with the decrease in cell count. Deoxynivalenol decreased the l-lactate concentration in the fluid supernatant of IPEC-J2 cells at 2.5 μm (p < 0.05) with a maximal effect at 10 μm of DON. To determine whether the altered lactate production may be linked to alterations of energy balance, we measured cellular ATP levels in IPEC-J2 cells. A significant decrease in ATP levels was seen at 48 h in a dose-dependent manner. It could be demonstrated that DON has a distinct cytotoxic effect on IPEC-J2 cells.  相似文献   
79.
This study investigated the effects of wood-derived biochar (BC) applied at 1% to a C-poor silty-loam soil in the drought-tolerant (D24) and in the drought-sensitive (P1921) Pioneer Hi-Bred maize hybrids in pot and field trials (NE Italy). D24 had better growth than P1921 under rain-fed conditions without irrigation and soil amendment. The addition of biochar increased root growth in D24 (+38% root area) and decreases it in P1921 (?9%) at the silking stage, while the fraction of finer roots (<250 µm diam.) was reduced in D24 and increased in P1921. This led both hybrids to maintain the maximum transpiration at a lower fraction of transpirable soil water (from 82% to 45% in D24, and from 46% to 22% in P1921). There were no significant variations in plant nutrient contents, productivity and in the protein and starch contents of the grains, whereas the lipid content was reduced by biochar, particularly in P1921 (2.6% vs. 3% DW, ?13%).

We conclude that biochar can be profitably used to enhance drought tolerance in maize, possibly due to improvements in the physicochemical characteristics and the water content of treated soils, although maximum benefits are expected in drought-tolerant hybrids through increased root elongation and transpiration.  相似文献   
80.
The Sersenk strain of goat pox virus first isolated in Iraq, grew on chorioallantoic membranes (CAM) of developing chicken embryos producing generalised large pocks, 2 to 3 mm in diameter, on the third day post-inoculation. The virus killed the inoculated embryos. Replication of the virus in primary cultures of lamb testis cells induced a cytopathic effect (CPE) and plaque formation characteristic of pox viruses. It was antigenically related to reference strains of goat pox and sheep pox viruses. The virus was sensitive to ether and chloroform, failed to agglutinate erythrocytes and was strictly pathogenic to goats.  相似文献   
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