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51.
52.
Uterus didelphys is a rare congenital abnormality of the reproductive tract. Although it occurs in various species, there are no published reports describing pregnancy outcome in association with this abnormality. Herein we describe a case of successful unilateral singleton pregnancy in a ewe incidentally found to have uterus didelphys during the course of a biomedical research study. The pregnancy was established using assisted reproductive techniques and interrupted in late gestation, at which point the abnormality was identified. Serial ultrasound assessment of foetal biometry revealed a normal foetal growth trajectory. Despite a 45% reduction in placentome number, total placentome weight was near normal secondary to compensatory placentome growth and development. To our knowledge, this is the first detailed report of normal foetal growth in an animal with uterus didelphys and illustrates the ability of the ovine placenta to adapt to a reduced number of placentomes and maintain foetal nutrient supply.  相似文献   
53.
Background: Dogs that harbor the naturally occurring ABCB1-1Δ polymorphism experience increased susceptibility to avermectin-induced neurological toxicosis as a result of deficient P-glycoprotein function. Whether or not the ABCB1-1Δ polymorphism affects susceptibility to toxicity of other P-glycoprotein substrate drugs has not been studied.
Hypothesis: Dogs that possess the ABCB1-1Δ mutation are more likely to develop hematologic toxicity associated with vincristine than ABCB1 wild-type dogs.
Animals: Thirty-four dogs diagnosed with lymphoma were included in this study.
Methods: Cheek swab samples were obtained from dogs diagnosed with lymphoma that were to be treated with vincristine. DNA was extracted from cheek swabs and the ABCB1 genotype was determined. Hematologic adverse drug reactions were recorded for each dog and graded according to the Veterinary Comparative Oncology Group's criteria for adverse event reporting (Consensus Document). In order to avoid possible bias, ABCB1 genotype results for a particular patient were not disclosed to oncologists until an initial adverse event report had been submitted.
Results: Dogs heterozygous or homozygous for the ABCB1-1Δ mutation were significantly more likely to develop hematologic toxicity, specifically neutropenia ( P = .0005) and thrombocytopenia ( P = .0001), after treatment with vincristine than ABCB1 wild-type dogs.
Conclusions and Clinical Implications: At currently recommended dosages (0.5–0.7 mg/M2), vincristine is likely to cause hematologic toxicity in dogs with the ABCB1-1Δ mutation, resulting in treatment delays and unacceptable morbidity and mortality. Assessing the ABCB1-1Δ genotype before vincristine administration and decreasing the dosage may prevent toxicity and treatment delays resulting from neutropenia or thrombocytopenia.  相似文献   
54.
Obesity is becoming a major health concern in horses because of its associations with insulin resistance, oxidative stress/inflammation, and laminitis. However, there is limited information on the prevalence of obesity in horses. The USDA National Animal Health Monitoring System (NAHMS) 1998 Equine study estimated that approximately 1.4% of the U.S. horse population is overweight or obese. The purpose of this study was to determine the prevalence of overweight and obesity in a subpopulation of horses in Virginia. A random sample of 300 mature, Light Breed horses (140 mares, 151 geldings, and 9 stallions) was selected from the VMRCVM Equine Field Service practice. Horses were evaluated during summer 2006. Body Condition Score (BCS) was assigned using a scale of 1 (emaciated) to 9 (obese) by two independent scorers. Neck circumference (cm) was measured at three locations and averaged (ANC). Girth, body length, and height at the withers were measured and used to calculate body weight (BW) and Body Mass Index (BMI). ANC and height at the withers were used to calculate Neck Circumference to Height Ratio (NCHR). Horses were categorized based on BCS as under condition (BCS <4), optimal condition (BCS 4–6), over condition (BCS 6.5–7), and obese condition (BCS 7.5–9). Six horses (2%) were under condition, 141 horses (47%) were in optimal condition, 96 horses (32%) were over condition, and 57 (19%) were obese. BW (p = 0.047), ANC, BMI and NCHR (all p < 0.001) increased with BCS. The prevalence of overweight and obesity in these horses was much higher than previously reported.  相似文献   
55.
The present study was designed to evaluate three different in vitro fertilization (IVF) systems: a straw‐IVF system with 10 min of coincubation, a straw‐IVF system with 6‐h coincubation and the microdrop‐IVF system with 6‐h coincubation (the traditional IVF system used routinely in most of IVF laboratories) in an attempt to reduce polyspermic penetration ( Experiment 1 ). When the straw‐IVF system was tested in combination with two coincubation times, the use of 10 min of coincubation significantly increased (p < 0.001) the penetration rate and the efficiency of fertilization (67.7 ± 6.4% vs 31.9 ± 6.5% and 41.5 ± 2.5% vs 17.6 ± 2.5% for 10 min and 6 h, respectively), while there were no significant differences in the incidence of monospermy between both systems (64.3 ± 5.1% and 67.7 ± 3.4%, for 10 min and 6 h, respectively). The penetration rate in the 6‐h microdrop‐IVF system was higher (93.8 ± 3.6%; p < 0.001) compared with the 10‐min straw‐IVF system (67.7 ± 6.4%), however, monospermy was severely reduced (25.0 ± 4.3% vs 67.7 ± 3.4%, for the 6‐h microdrop‐IVF system and 10‐min straw‐IVF system, respectively). The efficiency of the IVF showed similar values between microdrop and 6‐h straw‐IVF systems, but efficiency was significantly improved (p < 0.05) when the 10‐min straw‐IVF system was used. Experiment 2 was designed to compare porcine in vitro embryo production in two IVF systems, the 6‐h microdrop‐IVF system (1000 sperm per oocyte) and 10‐min straw‐IVF system (30 000 sperm per oocyte). The blastocyst formation rates tended (p = 0.06) to be higher when the 10‐min straw‐IVF system was used compared with the 6‐h microdrop‐IVF system. In addition, the number of total cells per blastocyst increased significantly (p < 0.05) in the 10‐min straw‐IVF system. These results showed that the 10‐min straw‐IVF system is an effective way to decrease polyspermic penetration, and improve the efficiency of fertilization and the quality of blastocysts in terms of cell number per embryo.  相似文献   
56.
57.
The anionic ruthenium cluster carbonylates [Ru6C(CO)16]2- or [H2Ru10(CO)25]2- interspersed with bis(triphenylphosphino)iminium counterions (PPN+) are incorporated from solution into the pores of MCM-41 mesoporous silica (3 nanometers in diameter), where they form tightly packed arrays. These arrays were shown by high-resolution transmission electron microscopy, Fourier transform optical diffraction, and computer simulations to be well ordered both along and perpendicular to the axis of the cylindrical pores. In their denuded state produced by gentle thermolysis, the cluster carbonylates yield nanoparticles of ruthenium that are less well ordered than their assimilated precursors but show good activity as hydrogenation catalysts for hexene and cyclooctene. In both their as-prepared and denuded states, these encapsulated clusters are likely to exhibit interesting electronic and other properties.  相似文献   
58.
Are extinctions of marine vertebrates as rare and unlikely as current data indicate? Long-term research surveys on the continental shelf between the Grand Banks of Newfoundland and southern New England reveal that one of the largest skates in the northwest Atlantic, the barndoor skate (Raja laevis), is close to extinction. Forty-five years ago, research surveys on St. Pierre Bank (off southern Newfoundland) recorded barndoor skates in 10% of their tows; in the last 20 years, none has been caught, and this pattern of decline is similar throughout the range of the species.  相似文献   
59.
The gate bias dependence of the field-effect mobility in pentacene-based insulated gate field-effect transistors (IGFETs) was interpreted on the basis of the interaction of charge carriers with localized trap levels in the band gap. This understanding was used to design and fabricate IGFETs with mobility of more than 0.3 square centimeter per volt per second and current modulation of 10(5), with the use of amorphous metal oxide gate insulators. These values were obtained at operating voltage ranges as low as 5 volts, which are much smaller than previously reported results. An all-room-temperature fabrication process sequence was used, which enabled the demonstration of high-performance organic IGFETs on transparent plastic substrates, at low operating voltages for organic devices.  相似文献   
60.
Scrub-itch mite infestation in the endangered bridled nailtail wallaby   总被引:1,自引:1,他引:0  
Skin lesions on the ears and inguinal and axillary regions of a number of adult animals within a captive population of the endangered bridled nailtail wallaby ( Onychogalea fraenata ) were associated with the trombiculid mite, Eutrombicula hirsti . The local inflammatory response of these Australian marsupials is described.  相似文献   
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