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The endometrial tissue of the uterus plays a key role in reproduction and is a source of hormones and factors responsible for the proper physiological function of reproductive tract during the oestrous cycle and pregnancy. In this study, we investigated the pattern of PGF(2alpha) and PGE(2) secretion from cultured porcine endometrial cells at different days of the oestrous cycle. Epithelial and stromal cells were isolated by differential enzymatic digestion on days 6-8, 10-12 and 14-16. After attachment cells were incubated for 3 and 24 h to estimate PGF(2alpha) and PGE(2) output. The purity of culture was 85-90% for epithelial and 95-98% for stromal cells as determined by immunofluorescent staining. Release of PGF(2alpha) and PGE(2) was affected by cell type, days of the oestrous cycle and the time of incubation. After 3 h of incubation epithelial cells secreted more PGF(2alpha) than PGE(2) during all studied periods of the oestrous cycle (p < 0.01 and p < 0.001, respectively), whereas stromal cells released more PGE(2) (p < 0.01) on days 10-12 and 14-16. Longer incubation of stromal cells revealed that PGF(2alpha) output tended to overcome PGE(2) on days 10-16. The lowest secretion of prostaglandins was observed on days 6-8 in both cell types. The highest secretion of PGF(2alpha) from epithelium was measured on days 10-12 after 24 h of incubation when compared with other days studied (p < 0.001). In stromal cells, PGE(2) output increased on consecutive days studied (p < 0.001) after 3 h of incubation. The differential properties of endometrial cell types seem to play an important role in the profile of PGF(2alpha) and PGE(2) release before and during luteolysis. Described endometrial cells culture might serve as the model for further studies on the hormonal regulation of prostaglandin production in the pig.  相似文献   
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All horses undergoing coeliotomy for an acute abdominal crisis are at risk of developing ileus and should receive therapy aimed at promoting gastrointestinal function by restoring fluid and electrolyte balance. Adequate analgesia and prevention against peritonitis, bacteraemia and endotoxaemia should be provided. Horses that at the time of surgery have a strangulating or non-strangulating small intestinal obstruction should be considered to be at greater risk of developing a persistent ileus that is refractory to treatment than those horses with lesions involving the large intestine. In horses considered to be at greater risk of developing a persistent ileus, the use of prokinetic agents should be considered. Agents that may be used to improve gastrointestinal motility include adrenergic receptor antagonists, cholinergic agonists, benzamides, dopamine antagonists, macrolide antimicrobials, opiate receptor agonists and antagonists, somatostatin analogues and local anaesthetics. There are limited studies into the use of these agents in the horse. Until further research provides more information on motility disorders following intestinal surgery and the efficacy of prokinetic agents in this species, only selective use of some of these drugs can be recommended.  相似文献   
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Social organization and breed effects following PGF2αwere studied in mature Angus, Brahman and Senepol cows allocated into two groups (each A = 5, B = 5 and S = 5). Variables including interval to oestrus onset (IEO), oestrous duration (DE), total mounts received (TMR), and oestrous intensity (IE) were derived via HeatWatch®. Breed‐type influenced IEO (B = 42.6 ± 6.7 h; S = 54.6 ± 6.0 h; and A = 27.8 ± 5.8 h; p < 0.003). Within breeds, dominant B (69.4 ± 13.3 h) and S (65.5 ± 7.4 h) cows were slower (p < 0.05) to be detected in oestrus than subordinate (38.1 ± 4.4 h) and intermediate (40.6 ± 6.0 h). However, within A, dominant cows (16.4 ± 12.5 h) were detected in oestrus earlier (p < 0.05) than intermediate (44.3 ± 9.2 h) and subordinates (32.7 ± 5.1 h). Angus (21.5 ± 2.4 h) and B (22.1 ± 3.0 h) cows had longer (p < 0.01) DE than S (9.1 ± 2.8 h). Dominants (20.4 ± 3.0) and intermediates (20.2 ± 2.3 h) cows had longer DE (p < 0.04) than subordinates (12.1 ± 2.1 h) although the interaction breed × social order showed that dominant S had shorter DE than dominant A and B (10.1 ± 3.3; 34.8 ± 6.0 h; and 20.0 ± 6.4 h, respectively; p < 0.001). Angus cows had less TMR than B (p < 0.02) and tended to be less than S cows (p < 0.06). Overall, greatest (p < 0.008) IE occurred in the first 9 h after onset of oestrus with no breed effect (p > 0.05). Dominant cows tended (p < 0.10) to have less TMR (3.2 ± 0.7 mounts) than subordinate (4.1 ± 0.4 mounts) and intermediate (4.7 ± 0.6 mounts) throughout, especially 3–6 h after oestrus onset (p < 0.07). Breed and social order both influence PGF2α‐induced oestrus behaviour.  相似文献   
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Objective: To establish normal parameters of thromboelastography (TEG) in healthy adult cats. Background: Thromboelastography (TEG) is an in vitro test of coagulation that has been shown to be useful in humans, dogs and select species to identify and quantify alterations of hemostasis (e.g., hypercoagulable and hypocoagulable states). It has also been demonstrated to be useful in monitoring effects of anticoagulant therapies. This test has not been evaluated in cats. Methods: Blood was collected from 25 clinically normal cats by venipuncture using a 21 gauge×3 1/2 inch butterfly catheter and syringe for medial saphenous or jugular venipuncture. A single 1.8 mL sample in 3.8% Sodium Citrate (9:1) was collected from each cat. Recalcified whole blood was analyzed 30 minutes following collection with the TEG® 5000 analyzer (Haemoscope, Niles, IL). Analysis temperature was 37.6°C. TEG parameters recorded included: R‐value (represents initial fibrin formation), K (time from R to standard fixed measure of clot firmness which represents contributions of platelets and fibrinogen), maximum amplitude (MA; represents absolute clot strength), and alpha angle (α; the slope of TEG tracing which represents rate of clot formation). The coagulation index (CI) was derived from the formula generated for humans to provide an overall assessment of whether the sample was hyper‐ or hypocoagulable. Results: Values for the 25 normal cat samples are reported as mean ±2 standard deviations. R=2.97; 1.23–4.72; K=1.54, 0.38–2.71; α=70.70, 57.76–83.65; MA=58.50, 45.26–71.74 and CI=2.27, 0.07–4.46. Compared to historical information obtained on normal dogs, cats have significantly shorter R and K and larger α, MA and CI. Conclusions: TEG does have reproducible performance when used to evaluate coagulation status in normal cats. Compared to dogs, normal cats favor a hypercoagulable state. Species‐specific normal values are necessary for interpretation of TEG results. This test bears potential value for use in future experimental and clinical work to investigate hemostasis in cats receiving anticoagulant therapies or in cats suffering from diseases such as cardiomyopathy which are thought to be associated with altered coagulation status.  相似文献   
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Chitosan is a natural non-toxic biopolymer and is widely used in various fields because of the antimicrobial activities. In this study, the properties of nylon textiles grafted with chitosan oligomer or chitosan polymer after being activated by open air plasma were evaluated. Results showed that nylon textiles grafted with chitosan polymer had better antibacterial performances than those grafted with chitosan oligomer. Air plasma activation at a higher speed (26 m/min) for a few times facilitated the grafting of chitosan and critically determined the antibacterial activities. Further treatment with air plasma after grafting improved the antibacterial effect. Overall, chitosan-grafted nylon textiles showed good antibacterial potential as well as biocompatibility.  相似文献   
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