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991.
Two domestic shorthair cats were presented with anorexia and dehydration following ingestion of caramelized onions. Shared key findings from a CBC (ADVIA 2120), serum biochemistry, and urinalysis included a spurious, marked leukocytosis with discordant basophil (BASO) channel and peroxidase channel WBC counts, normal manual leukocyte counts, mild, non-regenerative anemia with discrepancies between automated and manual reticulocyte counts, an abundance of large Heinz bodies (HBs), and highly irregular scattergrams. Case 1 also demonstrated a markedly elevated mean corpuscular hemoglobin concentration (MCHC) and discrepancies between RBC hemoglobin indices. Spurious leukocyte results were confirmed through re-analysis of samples (including the acquisition of a new sample, use of an alternate analyzer (Sysmex XT-2000iV; Case 1 only), and evaluation of scattergrams and blood films (Cases 1 and 2). Repeatedly discrepant reticulocyte counts were also identified. In both cases, the erroneous BASO WBC counts, discrepancies in reticulocyte counts and RBC indices, and atypical scattergrams were interpreted to result from various effects of the HBs. These cases emphasize the importance of reviewing blood films, interpreting scattergrams, and the usefulness of duplicate methods for determining various measurands on hematology analyzers.  相似文献   
992.
993.
994.
At periods greater than 1000 seconds, Earth's seismic free oscillations have anomalously large amplitude when referenced to the Harvard Centroid Moment Tensor fault mechanism, which is estimated from 300- to 500-second surface waves. By using more realistic rupture models on a steeper fault derived from seismic body and surface waves, we approximated free oscillation amplitudes with a seismic moment (6.5 x 10(22) Newton.meters) that corresponds to a moment magnitude of 9.15. With a rupture duration of 600 seconds, the fault-rupture models represent seismic observations adequately but underpredict geodetic displacements that argue for slow fault motion beneath the Nicobar and Andaman islands.  相似文献   
995.
The effects of relative humidity (RH) and temperature on tomato powdery mildew (Leveillula taurica) were studied in controlled environments to define conditions that affect disease development in fresh market tomatoes in California. Gradients of RH (20–90%) at constant temperatures (20–30°C) were generated in single growth chambers to determine their effect on mildew development on mature tomato plants. Temperatures of 30°C and above were deleterious for spore germination, germ tube elongation, and disease development. Lesion growth and rate of disease progress were significantly higher at 20°C than at 25°C. Low RH levels (20–40%) reduced spore germination and lesion growth, accelerated host tissue death and reduced disease progress. Intermediate RH levels (50–70%) increased spore germination and optimized disease development, provided temperatures were maintained within favorable limits. High RH levels (80–90%) were favorable for spore germination but continued exposure to these conditions led to a limited lesion growth and disease progress. Short daily periods (two or three daily exposures of at least 2 h) of high temperatures (35°C) suppressed disease development by 70–92%.  相似文献   
996.
Summary The reaction of 40 potato clones and six accessions ofSolanum spp. to wilt caused byVerticillium dahliae and to the acetone precipitate (AP) of the toxin produced by the pathogen in vitro was studied. There was a highly significant correlation between the wilt reaction of the clones in the glasshouse, the incidence and progress of wilt and severe wilt in the field, and the degree of colonization of stem apices byV. dahliae. Of the clones and accessions evaluated, NDA8694-3, Norgold Russet, BelRus, Superior, Russet Norkotah, Norland andS. demissum were the most susceptible, while A66107-51, A68113-4, Targhee, NDA843-3, Alpha, A7805-8, A7816-14, Russet Nugget,S. chacoense, S. sparsipilum, andS. tarijense were the most resistant to wilt. The reaction of genotypes to the AP ofV. dahliae toxin in an excised leaf bioassay was not correlated with their reaction to Verticillium wilt in the field or glasshouse. Idaho Agricultural Experiment Station Article No. 89741.  相似文献   
997.
Cerebellar abiotrophy (CA) is an uncommon neurological disease that most commonly affects Arabian horses. Affected horses are typically identified within the first 6 months of life. Intention tremor, wide based stance and ataxia are common clinical signs observed in affected individuals. No treatment is available for resolution of clinical signs. Definitive diagnosis is based on histopathological examination of cerebellar tissue, which is characterised by loss of Purkinje cell layer. This report describes a case of cerebellar abiotrophy that had a delayed diagnosis until 6 years of age.  相似文献   
998.
The major difficulty in providing the benefits of embryo cryopreservation for equine agriculture is the mismatch between the optimal embryo age for collection from the mare (7-8 days after ovulation was detected) and the optimal age for freezing under current methods (6.5 days after ovulation). To overcome this limitation, we tested a method to enhance penetration of cryopreservative across the capsule and trophoblast of day 7 and 8 embryos combined with rapid freezing by vitrification. Six small embryos (<300 μm in diameter) were collected on day 6-7 after ovulation and twelve larger embryos were recovered on day 7-8. In the treatment group, replacement of blastocoelic fluid with cryopreservative solution was facilitated by a laser system used to create a small opening in the embryonic capsule and trophectoderm. All embryos were vitrified using a CryoLeaf freezing support. After recovery from freezing and embryo transfer, three of four small untreated embryos (<300 μm in diameter, 75%) and four of nine large blastocysts in the treatment group (>300 μm in diameter, 44%) resulted in a vesicle as detected by ultrasonography approximately one week after transfer. However, only one recipient mare was still pregnant on day 23, and she delivered a live foal. Further investigation is required to determine why most of the embryos in this experiment were lost between day 13 and day 23 of gestation.  相似文献   
999.
Leukotoxin (Lkt) and LPS are the major virulence determinants of Mannheimia haemolytica that contribute to the pathogenesis of bovine and ovine pneumonic pasteurellosis. We have previously identified bovine and ovine CD18 as the functional receptor for Lkt. LPS complexes with Lkt resulting in increased thermal stability and enhanced cytotoxic activity of Lkt. Cellular recognition of LPS involves several different molecules including CD14. We hypothesized that expression of ovine CD14 together with LFA-1 or Mac-1 would enhance Lkt-induced cytotoxicity. Ovine cDNA for CD14 was amplified by PCR and cloned into mammalian expression vectors. The 1122 bp cDNAs for bighorn sheep (BHS) and domestic sheep (DS) CD14 encode 373 amino acids which exhibit 99% identity with each other. Ovine CD14 plasmids were transfected either into HEK-293 cells, or previous HEK-293 transfectants stably expressing ovine LFA-1 or Mac-1. Flow cytometric analysis of transfectants confirmed the cell surface expression of CD14. The transfectants expressing LFA-1 or Mac-1 and the transfectants co-expressing CD14 with LFA-1 or Mac-1 did not show any significant difference in Lkt-induced cytotoxicity when incubated with LPS complexed Lkt. In contrast, incubation of the LFA-1 or Mac-1 and LFA-1/CD14 or Mac-1/CD14 transfectants with Lkt which lacks LPS, resulted in reduced cytotoxicity. None of the above transfectants showed any difference in [Ca2+](i) elevation when incubated with both types of Lkt preparations. Lkt did not induce any cytotoxicity or [Ca2+](i) elevation in ovine CD14 transfectants or parent HEK-293 cells. Based on these findings, we conclude that expression of CD14 together with LFA-1 or Mac-1 does not enhance Lkt-induced cytotoxicity, whereas LPS enhances cytotoxicity by complexing with Lkt.  相似文献   
1000.
Canine heartworm infection has been associated with glomerular disease and proteinuria. We hypothesized that proteinuria, likely due to glomerular damage, would also be found in cats experimentally and naturally infected with Dirofilaria immitis. Two populations of cats were evaluated, including 80 that were each experimentally infected with 60 infective heartworm larvae as part of a drug safety study, and 31 that were naturally infected with D. immitis. Each had a control population with which to be compared. In the experimentally infected group, we evaluated urine from 64 cats. Ten of these cats were shown to have microalbuminuria 8 months post infection. No cat refractory to infection with larvae and no cats from the control group demonstrated microalbuminuria. All 10 microalbuminuric cats were shown to have significant proteinuria, as measured by the urine protein:creatinine ratio. There was a subtle, but significant, association between worm burden and proteinuria, and although the presence of adult heartworms was required for the development of proteinuria, both microfilaremic and amicrofilaremic cats were affected. Neither the presence of circulating heartworm antibodies and antigen nor the presence of antigenuria predicted the development of proteinuria. Both heavily infected cats (5-25 adult heartworms) and cats with worm burdens compatible with natural infections (1-4 adult heartworms) developed proteinuria, and the relative numbers of cats so affected were similar between heavily and more lightly infected cats. Naturally infected cats, for which only dipstick protein determinations were available, were shown to have a significantly greater incidence of proteinuria (90% vs 35%) than did those in an age- and gender-matched control population. Additionally, the proteinuria in heartworm-infected cats was 3- to 5-fold greater in severity. We conclude that cats infected with mature adult heartworms are at risk for developing proteinuria and that this is recognized relatively soon after infection. While heavier infections may predispose cats to developing proteinuria, this complication is seen in naturally infected cats and experimental cats with worm burdens similar to those seen in natural infections (i.e., "clinically appropriate" worm burdens). The clinical relevance of heartworm-associated proteinuria is yet to be determined.  相似文献   
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