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991.
Since the normal absorption of CSF occurs in the cerebral veins and venous sinuses, any obstruction to the normal flow and absorption of CSF will result in accumulation of CSF central to the site of obstruction. Such accumulation within the cranium is defined as hydrocephalus.A foal was presented with an enlarged and an abnormally-shaped skull, but with normal behavior. The filly's condition deteriorated. Radiographs showed a domeshaped cranial vault with compression of the frontal sinus region. Massive hydrocephalus with little normal cerebral tissue left was diagnosed with ultrasound.Surgery was attempted to relieve the pressure. Eventually the foal was euthanized. Post-mortem confirmed the radiographic and ultrasound diagnosis. Since there was a lack of demonstrable obstruction, the authors suspected the foal had suffered from the Arnold-Chiari syndrome.  相似文献   
992.
An anabolic steroid, nandrolone decanoate, was shown to produce increases in the weight, cross-sectional area, tension-generating capacity and mean fibre diameter of a limb muscle, tibialis anterior (TA), in female rabbits. Despite suggestions in the literature of an exerciserelated effect of such drugs, hypertrophy was not observed in TA muscles subjected to chronic electrical stimulation, but was seen in the contralateral control muscles and in the muscles of both hind limbs in unoperated sedentary animals. The effect was confirmed in the TA of female guinea pigs, rats and mice, and could not be explained in terms of an increase in body weight. Compared to TA some other muscles, like EDL, plantaris and soleus in the rabbit, were less sensitive to treatment; others, like pubocaudalis in the rat and mouse, and temporalis in the guinea pig, were more responsive. The myotrophic effects were undiminished in adrenalectomised female rats, and could not therefore have been mediated by interference with the catabolic actions of circulating glucocorticoids, as had been proposed in an earlier hypothesis.  相似文献   
993.
1. Broilers were fed on wheat‐casein or wheat‐soyabean meal diets and the excreta collected after 12 and 24 h. Samples of excreta were freeze dried or dried in a force draught oven at 60 or 80 °C.

2. Drying procedure and collection time significantly influenced the determined energy and nitrogen concentrations of the excreta.

3. Drying excreta in an oven at 60 °G proved at least as effective as freeze drying for the majority of amino acids.  相似文献   

994.
Depletion of cytoplasmic esterase-positive canine peripheral blood monocytes from mononuclear cell suspensions was attempted using plastic adherence, carbonyl iron ingestion and/or Sephadex G-10 filtration. An esterase-positive, nonadherent, nonphagocytic subpopulation was identified and further characterized by the presence or absence of cell membrane receptors for the Fc portions of immunoglobulin and the activated third component of complement. The majority of these nonadherent cells lacked these receptors. The data suggests that canine peripheral blood monocytes are a heterogenous cell population.  相似文献   
995.
The concentrations of cyclic 3':5'-adenosine monophosphate (cyclic AMP) and cyclic 3':5'-guanosine monophosphate (cyclic GMP) were determined in white light- and dim red light-adapted golden Syrian hamster retinas. Retinas from animals in dim red light had cyclic AMP concentrations of 9.29 +/- 2.94 pmol/mg of protein and cyclic GMP concentrations of 110.62 +/- 32.98 pmol/mg of protein. After white light adaptation, retinal cyclic AMP and cyclic GMP concentrations were reduced to 74% and 45% of the previous values, respectively. In another experiment with white light-adapted animals, the sex or method of immobilization of the animals (cervical dislocation vs sodium pentobarbital) had no significant effect on cyclic nucleotide values.  相似文献   
996.
Bile duct obstruction was induced in 6 cats by surgical ligation and transection of the common bile duct. Clinical and laboratory changes were monitored weekly for 25 to 54 days. Clinical signs of obstruction were similar in all cats and included anorexia, pyrexia, lethargy, intermittent vomiting, weight loss, palpable gallbladder, hepatomegaly, and bleeding tendencies. Tissue jaundice and acholic feces were evident grossly as early as postsurgical day (PSD) 4 with a mean onset of jaundice at PSD 5.3 +/- 0.4. Hematologic changes were initially characterized by a mild neutrophilic leukocytosis that increased with the chronicity of bile duct obstruction. Regenerative anemia developed in 4 cats associated with gastrointestinal blood loss. Acute serum biochemical changes were characterized by a marked increase in the mean values of aspartate aminotransferase, alanine aminotransferase, total cholesterol, and copper. Comparatively, only moderate increases in mean serum alkaline phosphatase activity were observed. Mean total bilirubin values increased remarkably at postsurgical week (PSW) 1, reaching a maximal value of 23.1 +/- 4.4 mg/dl at PSW 3 with 71.6 +/- 2.7% direct bilirubin. With chronicity of bile duct obstruction ranging from PSW 3 to PSW 7, the mean serum values of aspartate aminotransferase, alanine aminotransferase, total cholesterol, serum alkaline phosphatase, and total and direct bilirubin stabilized and then declined, whereas the increased mean serum copper values persisted. At PSD 25 to 54, hepatic copper values and serum bile acids were markedly increased. Seemingly, clinicopathologic changes of induced cholestatic hepatic injury depended largely on the duration of biliary obstruction.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
997.
A 31-year-old captive male African elephant (Loxodonta africana) of 5,000-kg body weight died suddenly in ventral recumbency. Lesions seen at necropsy were bilateral purulent pulpitis and periodontitis of both tusks, serous atrophy of coronary groove fat, Grammocephalus cholangitis, myocardial and skeletal lipofuscinosis, and scattered segmental necrosis in the pectoral muscles. Nonhemolytic streptococci, Corynebacterium sp, Peptostreptococcus anaerobius, Fusobacterium nucleatum, and Bacteroides sp, were recovered from the exudate around one or both tusks. We postulated that the elephant died of hypoxia from prolonged ventral recumbency because of weakness and inability to rise secondary to toxemia from bilateral pulpitis and periodontitis.  相似文献   
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