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991.
Coastal bermudagrass hay was labeled with Cr by the Cr-mordant procedure and with 177Lu applied to the same fiber. Neutral detergent fiber prepared from the same Coastal bermudagrass hay was labeled with Yb, 169Yb, Tb and 160Tb by soaking overnight following by thorough washing and drying. Wood chips were similarly labeled with Sm or La, and Solka Floc was labeled with 147Nd and 141Ce. The carriers, labels and times of administration to cattle were: bermudagrass fiber with both Cr and 177Lu, bermudagrass fiber with 169Yb and Solka Floc labeled with 147Nd at 0 h; bermudagrass fiber with Yb, Solka Floc with 141Ce and wood chips with Sm at 24 h; wood chips with La at 48 h; and bermudagrass fiber labeled with 160Tb at the beginning and labeled with Tb at the end of a meal. Fecal collection followed and passage characteristics were determined with a two-compartment, age-dependent model. Markers labeling the different fiber sources had different (P less than .01) passage rates (Solka Floc greater than Coastal bermudagrass greater than wood chips), but there was no difference within fiber source for rare earth passage. There also was no difference between the passage characteristics of Cr-mordant and 177Lu. However, passage rate of particles administered at the beginning of the meal (160Tb) was 42% higher than for particles at the end of the meal (Tb).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
992.
The addition of conditioned medium from murine L929 fibroblasts (MGF) to cultures of swine peripheral blood mononuclear cells (MNL) resulted in growth of cells of macrophage/monocyte lineage (MO). Glass-adherent swine MNL, shown to be greater than 95% phagocytic MO, grew in the presence of MGF, whereas swine blood granulocytes and lymphocytes were not MGF-responsive. Primary and secondary MO growth were directly dependent on MGF presence and concentration. MGF-stimulated MO synthesized DNA, as measured by cellular incorporation of tritium-labeled thymidine (3H-TdR). This mitogenic response was maximal by 5 to 6 days in primary MO cultures and declined thereafter to a lower magnitude in secondary MO cultures. In the presence of MGF, viable MO numbers increased with an approximate population doubling time of 5 to 7 days in primary culture. This growth rate was prolonged, to about 10 to 12 days, for MGF-stimulated MO in secondary cultures. MGF removal from primary and secondary MO cultures resulted in rapid growth cessation and cell death. MGF-stimulated MO could not be sustained in secondary culture beyond 7 weeks. MGF-cultured MO were positive for latex phagocytosis, non-specific esterase, Fc-receptor expression, and could mediate antibody-dependent cell-mediated cytotoxicity. The MO-mitogenic principle of MGF was identified as the murine, macrophage-specific colony-stimulating factor, CSF-1 (M-CSF). The swine MO-proliferative response to MGF was inhibited by addition of monospecific goat antisera to M-CSF. Purified M-CSF stimulated the growth of swine MO from cultures of MNL and primary glass-adherent MO.  相似文献   
993.
Scimitar horned oryx (Oryx dammah), kept under confined and unconfined conditions were immobilised with etorphine in combination with acepromazine or xylazine or both, and with xylazine alone. Both groups of animals were successfully sedated with etorphine and xylzine, with or without acepromazine, although hypothermia and mild hypoxaemia and a fall in packed cell volume were frequently noted. Xylazine alone produced a dose dependent degree of sedation in semitame subadult animals kept in confinement, but only slight depression in their wild, unconfined counterparts. If xylazine was not included in the immobilising mixture induction was traumatic and full sedation not achieved. Heart rates and arterial pressures (systemic and pulmonary) were also monitored but no remarkable changes were noted. The only abnormalities in blood biochemistry were raised aspartate transminase and creatine kinase. Ruminal regurgitation could be a major problem if endotracheal intubation was not achieved early in the procedure.  相似文献   
994.
Ten low (LSC) and 10 high (HSC) serving capacity yearling bulls were exposed individually to 25 naturally cyclic (N) cows for 3 d (average mating load) and subsequently to 9 estrus-synchronized (S) cows for 1 d (heavy mating load) in a randomized complete block design consisting of 10, 4-d blocks. Bulls were fitted with vibracorders and temperature acquisition modules to record grazing activity and body temperature (BT), respectively. During the N cow treatment, LSC bulls had fewer (P less than .05) services per cow and a higher mount to service ratio than HSC bulls, and LSC bulls tended (P = .12) to graze less total time than HSC bulls (7.8 vs 9.0 h/d, respectively). However, both groups of bulls exhibited similar diurnal grazing patterns with two major daily grazing periods; the first (0400 to 1300) peaked early in the morning (0600) and the second (1700 to 2200) occurred in late afternoon and evening. During the S cow treatment, LSC and HSC bulls did not differ (P = .60) in grazing time or pattern, but similar mating activity was exhibited by both SC groups while exposed to S cows. Bulls grazed little during the hottest part of the day (1300 to 1700), and LSC and HSC bulls spent only 2.2 and 2.4 h, respectively, grazing during dark, cooler periods near midnight. Body temperature did not differ between SC groups and averaged 39.3 degrees C during N cow treatment and 39.4 degrees C during S cow treatment. Body temperature had a distinct, monophasic diurnal pattern in bulls exposed to an average mating load.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
995.
Cystic alterations of the canine endometrium compromise reproduction and fertility of the bitch and may lead to life-threatening diseases, such as pyometra. Even without clinical evidence, reduction of the uterine lumen by cysts implicates disturbances during migration, nidation and development of the embryo. Several studies point to the high variability of morphology of uterine endometrial cysts but they lack detailed analyses of alterations. In the present study, immunohistochemistry was used to investigate the expression of steroid hormone receptors (oestrogen, progesterone), proliferation activity, inflammation and infection in the cystic affected tissue regions in contrast to the normal endometrium. Oestrogen receptor expression showed a high density of receptors throughout the surface epithelial cells, crypt epithelial cells, glandular epithelial cells and stromal cells of the normal endometrium as well as the cystic affected regions. Proliferation in the cysts was verified in the middle and basal cells of the crypts. Neither in the endometrium nor in the cysts inflammatory processes or evidence of infection could be detected. Furthermore, lectin histochemistry and electron microscopic methods showed that lectin binding patterns and cell morphology of internal epithelial lining and surface epithelium of the cysts can be used to characterize and distinguish different types of cystic alterations. Analogies between epithelial cells of the glandular chambers of the canine placenta and the cystic cellular morphology, steroid hormone receptor distribution as well as lectin binding patterns of the endometrial cysts, as observed in this study, suggest to introduce the term 'pseudo-placentational endometrial cysts'.  相似文献   
996.
Second-opinion histopathology is intended to detect clinically significant discrepancies that have a direct impact on patient care. We sought to determine if this practice at our institution affected patient management and prognosis. First- and second-opinion histopathology reports from cases were retrospectively reviewed. Reports were considered to be in diagnostic agreement, partial diagnostic disagreement or complete diagnostic disagreement. Four hundred and thirty cases were studied. In 70% of cases there was a diagnostic agreement. In 20% of cases, there was partial diagnostic disagreement, where diagnoses were the same but information such as grade or lymphatic and/or vascular invasion was changed. In 10% of cases, complete diagnostic disagreement resulted from a change in degree of malignancy (malignant to benign, or converse; 7%) or a change in cell type (3%). In 17% of the cases evaluated, the histopathology review prompted a change in treatment or prognosis. These findings support the use of second-opinion histopathology as an important part of patient care.  相似文献   
997.
998.
Cricopharyngeal achalasia is a rare cause of dysphagia in the dog. However it must be differentiated from other causes of dysphagia as it is treatable with surgery. It is a disruption of the cricopharyngeal phase of the oropharyngeal phase of deglutition. There appears to be an incoordination in the swallowing process between the relaxation of the rostral, middle pharyngeal muscles and the caudal pharyngeal muscles. It is seen as a primary condition in young animals presenting soon after weaning onto solid food. The dogs appear clinically healthy unless there is secondary aspiration pneumonia or emaciation. These dogs may present as respiratory emergencies and require intensive support and treatment prior to corrective surgery. The diagnosis is made on videofluoroscopy. The condition carries a good prognosis for cure with surgical myectomy of the cricopharyngeal muscle and the thyropharyngeal muscle, which make up the upper oesophageal sphincter. Temporary relief prior to surgery can be achieved by injection of the cricopharyngeal muscle with botulism toxin. Surgical treatment for dysphagia secondary to an underlying neurological, neuromuscular or pharyngeal weakness carries a guarded prognosis and will make aspiration pneumonia worse.  相似文献   
999.
1000.
Reasons for performing study: Feed supplements are commonly used by owners to alleviate headshaking; however, randomised, controlled trials are required to assess their efficacy. Objective: To determine the efficacy of a feed supplement for alleviation of the clinical signs of headshaking using a randomised, blinded, placebo‐controlled trial. Methods: Using a crossover design, 44 horses previously diagnosed with chronic idiopathic headshaking received both the supplement and a matching placebo per os for 28 days with a washout period between of 14 days. Video recordings were taken at rest and exercise prior to the study and at the end of both periods of treatment. The degree of headshaking was assessed in a blinded, randomised manner by 2 veterinary surgeons. At the same time points, owners completed a questionnaire to assess the severity of headshaking signs. A Wilcoxon signed rank test was used to compare the scores while on supplement and placebo. Results: Using the video assessments, there was no significant difference between scores while on supplement compared with placebo (P = 0.7). Using the questionnaire responses, there was no significant difference between scores for any activity when the placebo and the supplement were compared with each other. However, owners reported significant improvement during all activities for both placebo and supplement compared with pretreatment scores. Conclusions and potential relevance: The supplement offered no benefit over a placebo in alleviating the clinical signs of headshaking. There appeared to be a significant proxy placebo effect when the outcome was based on subjective owner perception of clinical signs. This study demonstrated no beneficial effect of this supplement on the clinical signs of headshaking. The study did show a significant placebo effect, thereby highlighting the necessity of properly conducted, randomised controlled trials, with blinding, to assess true treatment effects in trials in animals.  相似文献   
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