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91.
A critical period of early gestation in the mare involves the immobilization (fixation) of the encapsulated conceptus at around days 16–17. We compared the major proteins in the normal equine embryonic capsule and endometrial secretions around the period of fixation with those from pregnancies in the process of termination induced by administration of an analogue of prostaglandin F (PGF). Uterocalin and β2-microglobulin (β2M) associated with the embryonic capsule were proteolytically converted to smaller forms during the fixation period. These conversions were similar in conceptuses from control and treated mares. A 17 kDa cationic protein identified as a secretory phospholipase A2 (sPLA2) type IIA was detected bound to normal capsules but increased substantially in response to PGF. Two forms of uteroglobin were distinguished by partial amino acid sequences of ∼6 kDa bands in flush fluids from normal pregnant uteri. After administration of PGF one immunoreactive form of uteroglobin was preferentially increased. These studies demonstrate that failure of pregnancy in this model is associated with an increase in secretory phospholipase in the capsule and a change in the forms of uteroglobin in the uterine secretions.  相似文献   
92.
Chemotherapy‐induced diarrhoea (CID) is a frequent chemotherapy adverse event in dogs. Yet, there is currently no consensus regarding its management. Smectite is a natural medical clay, widely used in the treatment of acute diarrhoea in humans. The objectives of this study were to assess the efficacy of smectite in the management of CID in dogs, and to collect epidemiological data on CID. For each episode of diarrhoea, dogs were randomized into two management groups: Smectite group, receiving smectite at 0.5 g/kg PO per day divided in two to three doses initiated at the start of CID; control group, without initial medication. In both groups, rescue metronidazole was prescribed if CID progressed or was not improved within 48 hours. Sixty dogs were recruited and received 426 chemotherapy administrations between June 2017 and March 2019. The incidence rate of CID was 110/426 (25.8%, 95% CI: 21.7%‐30.2%), and significantly differed between the chemotherapeutic drugs administered (P < .001). Metronidazole was administered in 5/54 events (9.3%, 95% CI: 3.1%‐20.3%) in the smectite group and in 40/56 events (71.4%, 95% CI: 57.5%‐82.3%) in the control group (P < .001). The time to resolution of diarrhoea was shorter (P < .001) in the smectite group (median: 19.5 hours, interquartile range [IQR]: 13.5‐32 hours) compared with the control group (median: 53 hours, IQR: 31.5‐113.5 hours). The results of this study support the administration of smectite in the first‐line management of CID in dogs.  相似文献   
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Seven five-week piglets were infected intranasally with 10(5) TCID50 of porcine reproductive and respiratory syndrome (PRRS) virus strain IAF.exp91. All virus-exposed pigs developed fever, labored abdominal breathing, conjunctivitis, and lymph node enlargement within the first 96 h postexposure (PE), which continued to d 10 to 14 PE. Two pigs that were necropsied at d 7 and 10 PE had diffuse interstitial pneumonitis, cardiopathy and lymphadenopathy. All 5 remaining pigs produced serum IgM and IgG antibodies against PRRS virus by 7 or 14 days PE, as demonstrated by indirect immunofluorescence. This corresponded with the capability of isolating the virus from serum d 7 to d 49 or d 63 PE. Low serum neutralizing antibody titers were detected in 3 of the virus-exposed pigs by 35 days PE. A transient episode of diminished proliferative response of peripheral blood lymphocytes to mitogens phytohemagglutinin (PHA) and concanavalin A (Con A) was observed in the virus-exposed pigs at d 3 PE. However, in vitro spontaneous uptake of [3H]-thymidine was significantly increased in lymphocyte cultures of the same pigs at d 7 or d 14 PE. These results suggest polyclonal activation of peripheral blood lymphocytes.  相似文献   
95.
Clinical and subclinical endometritis are common causes of infertility and subfertility in high producing dairy cattle, delaying the onset of ovarian cyclic activity after parturition, extending luteal phases and reducing conception rates. Escherichia coli and Arcanobacterium pyogenes cause endometrial damage and inflammation. Components of microbes, such as lipopolysaccharide (LPS), are detected by Toll-like receptors on endometrial cells, leading to secretion of cytokines, chemokines and antimicrobial peptides. Long luteal phases associated with endometritis are probably caused by a switch in endometrial prostaglandin production from prostaglandin F2a (PGF) to prostaglandin E2. In addition, LPS impairs the function of the hypothalamus and pituitary, and directly perturbs ovarian granulosa cells steroidogenesis, providing mechanisms to explain the association between uterine disease and anovulatory anoestrus. Cows with uterine disease that ovulate have lower peripheral plasma progesterone concentrations that may further reduce the chance of conception associated with endometritis.  相似文献   
96.
In France, corn rootworm (Agriotes sp.) is controlled by applying insecticides such as carbofuran to the soil. In recent years, the failure of carbofuran to control this pest has been observed in the south-west area of France in continuous corn cropping. A soil survey was conducted in order to determine the main factors which could influence carbofuran degradation in various soils. Degradation estimates were based on measurement of the release of [ 14 C]carbon dioxide from [carbonyl- 14 C]carbofuran. The enhanced degradation of carbofuran observed in laboratory conditions corresponded to the growth of micro-organisms able to use carbofuran as sole carbon and nitrogen source. The size of this microbial population and the rates of carbofuran degradation were higher in the samples taken from plots with a history of carbofuran use than in samples from previously untreated plots. Abiological degradation was only observed in alkaline soil conditions. Statistical analyses showed that carbofuran-degrading activity was not related to any particular pedological characteristics.  相似文献   
97.
This is the first published report of a dog with dynamic right ventricular outflow tract (infundibular) stenosis, right ventricular hypertrophy, and pectus excavatum. A juvenile dog presented with a grade V/VI left base systolic heart murmur, tachycardia, and pectus excavatum. Diagnosis of the aforementioned conditions was based on radiography, electrocardiography, and echocardiography. At 9 1/2 wk of age the heart murmur was no longer audible and the right ventricular stenosis and hypertrophy had dissipated and regressed, respectively. Resolution may be associated with growth of the dog. A good prognosis is foreseen.  相似文献   
98.
Properly fashioned electromagnetic fields coupled to microscopic dielectric objects can be used to create arrays of extended crystalline and noncrystalline structures. Organization can be achieved in two ways: In the first, dielectric matter is transported in direct response to the externally applied standing wave optical fields. In the second, the external optical fields induce interactions between dielectric objects that can also result in the creation of complex structures. In either case, these new ordered structures, whose existence depends on the presence of both light and polarizable matter, are referred to as optical matter.  相似文献   
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