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31.
Isolated diatomic molecules of iodine monochloride (ICl) were photodissociated by a beam of linearly polarized light, and the resulting ground-state Cl atom photofragments were detected by a method that is sensitive to the handedness (helicity) of the electronic angular momentum. It was found that this helicity oscillates between "topspin" and "backspin" as a function of the wavelength of the dissociating light. The helicity originates solely from the (de Broglie) matter-wave interference of multiple dissociating pathways of the electronic excited states of ICl. These measurements can be related to the identity and to the detailed shapes of the dissociating pathways, thus demonstrating that it is possible to probe repulsive states by spectroscopic means.  相似文献   
32.
Apparent restihg energy expenditure (AREE) and respiratory quotient (RQ) were determined by open flow indirect calorimetry in a group of 104 apparently resting, critically ill, postoperative and severely traumatized dogs. The evaluations were conducted in a calm, temperature-controlled environment after at least a 12-hour fast. Subjects were allowed to acclimilate to the monitoring equipment prior to beginning the study. The clinical patients were compared to a group of 20 clinically normal, apparently resting, client owned dogs (NC). The data was also compared to published normals (NP) for energy expenditure of apparently resting dogs. Measurements were indexed to actual body weight in kilograms (BW) as well as to metabolic body size(BW0.75). Measurements of VO2 (VO2/kg and VO2/kg0.75) and VCO2 (VCO2/kg and VCO2/kg0.75) were used to calculate the RQ and the AREE. Critically ill, postperative and severely lower RQ values AREE/kg or AREE/kg0.75 (p=0.39). The PO&T dogs did exhibit significantly lower RQ values (p<0.0001) than either the (NC) or (NP) groups. Measured AREE of the PO&T dogs was significantly less than a calcualted value using the illness/injury/infection energy requirement (IER), (p<0.0001). Energy expenditure in typical trauma and postoperative patients may commonly be overstimated by the IER method. Conclusion: The AREE of critically ill, postoperative and severly trumatized dogs was not higher than healthy dogs as has been previously suggested in the literature.  相似文献   
33.
The aim of this study was to describe the scintigraphic appearance and location of the sacroiliac joint (SI-joint) in dorsal and dorso 30 degree lateral views of the equine pelvis in a scintigram. The pelvis from 10 different horses was prepared by attaching plastic tubes along relevant margins of the bone and around the SI-joint. A radioactive solution was injected into the tubes, and scintigraphic images were acquired with a gamma camera. Five specific landmarks were identified on the left and right sides of the pelvis. There was no significant difference in the distance measurements between the left and right sides in the dorsal view. The SI-joint was roughly ovoid in shape, with its long axis angled to the midline. The most craniolateral point of the SI-joint (Y) was located at the middle (SD = 0.04) of a line drawn from the caudal margin of the tuber sacrale (TS) to the craniolateral margin of the tuber coxa (TC), which was called TS-TC. In 85% of the specimens, the long axis of the SI-joint (SILA) was located caudal to or intersecting TS-TC, and the mean angle between SILA and TS-TC was 16.4 degrees (SD = 5.6 degrees). The distance from the caudomedial point of the SI-joint (Z) to Y was 0.38 times (SD = 0.04) the length of TS-TC. The distance from the tuber sacrale to the medial border of the SI-joint (TS-X) was 0.15 times (SD = 0.02) the length of TS-TC. In the oblique view, the SI-joint appeared wider and was positioned more laterally compared to the dorsal view. The distance TS-Y increased to 0.61 times (SD = 0.046) TS-TC, but SILA/TS-TC was essentially unchanged. The mean angle between TS-TC and SILA increased to 20.9 degrees (SD = 5.6 degrees). TS-X increased to 0.31 times (SD = 0.037) TS-TC. The location of the SI-joint was very similar in all horses, which makes it possible to estimate the location of the SI-joint in a scintigram in which the tuber sacrale and the craniolateral margin of the tuber coxa are identified.  相似文献   
34.
Objective To measure the plasma cortisol response in lambs castrated and docked by three different methods (ring castration and tail docking, ring and clamp castration and tail docking; ring and clamp castration and ring tail docking) for 4 h after treatment.
Design A physiological study with controls.
Procedure A rubber ring was applied to the scrotum. Then the castration clamp was placed, distal to the ring, on each spermatic cord such that there was no overlap of the crush lines.
Results There were no differences in the cortisol secretion of the lambs castrated and tail docked by the ring only and by the ring plus castration clamp methods. Using the castration clamp in addition to the ring on the tail had no effect on cortisol secretion.
Conclusions Using the castration clamp did not appear to reduce the cortisol response to ring castration and docking, as demonstrated elsewhere, because the areas of uncrushed tissue between the two castration clamp crush lines allowed nociception from ischemic scrotal tissue to be transmitted cranially via undamaged nerve fibers.  相似文献   
35.
A controlled period of submaximal exercise on a treadmill was used as a standardised stress test in 6 young horses to monitor the effects of training. Circulating plasma concentrations of immunoreactive beta-endorphin (IR beta-EP) were measured before, during and after the exercise period. The stress test was conducted on 3 occasions during an intensive training program lasting 14 weeks. In week 3 a marked increase in plasma IR beta-EP (P = 0.003) was demonstrated as a result of training, but by the last exercise test performed in week 9 no significant increase in plasma IR beta-EP concentrations could be detected. During the training period the basal concentrations of plasma IR beta-EP significantly decreased (P = 0.0059). Plasma adrenocorticotrophin (ACTH) did not increase during exercise, although there was a trend of decreasing basal plasma ACTH by the end of the training period. It was concluded that a standardised work test acted as a mild stress to unfit horses, but as the horses' fitness increased the hormonal response to exercise diminished. Basal plasma beta-EP concentrations were decreased with increasing fitness.  相似文献   
36.
To ensure sufficient numbers of pregnant females, particularly at hotter times of the year, hormonal induction of gilt oestrus may be necessary. However, the gilt oestrus and ovulation responses to gonadotrophin treatment have often proven unpredictable. The objective of this study was to examine possible reasons for this unpredictability. Prepubertal gilts (approximately 150 days of age, n = 63) were assigned to one of three treatments: injection of 300 IU hCG (n = 15); pre-treatment with 100 mg FSH in polyvinylpyrrolidinone administered as 2 × 50 mg injections 24 h apart, followed by 600 IU eCG at 24 h after the second FSH injection (n = 23); or FSH pre-treatment as above followed by 300 IU hCG at 24 h after the second FSH injection (n = 25). To facilitate oestrus detection, gilts were exposed to a mature boar for 15 min daily for 7 days. Blood samples were obtained on the day of eCG or hCG injection and again 10 days later and gilt ovulation responses determined based on elevated progesterone concentrations. The oestrus responses by 7 days were 6.7%, 17.5% and 64.0% for gilts treated with hCG, FSH + eCG and FSH + hCG, respectively (p < 0.001). The oestrous gilt receiving hCG alone and one oestrous FSH + hCG gilt did not ovulate, all other oestrous gilts ovulated. A further two anoestrous FSH + eCG-treated gilts ovulated. These data suggest that FSH pre-treatment facilitated the development of ovarian follicles to the point where they became responsive to hCG, but had little effect on the response to eCG.  相似文献   
37.
38.
Frozen-thawed (FT) boar sperm have a reduced fertile life, due in part to a capacitation-like status induced by cooling. Reversal of this cryocapacitation in vitro by exposure to boar seminal plasma (SP) has been demonstrated. The objective of these studies was to determine the effect of SP on the ability of FT sperm to create an oviductal sperm reservoir following artificial insemination (AI). In Experiment one, 35 pre-pubertal gilts were injected (IM) with 400 IU eCG plus 200 IU hCG to induce oestrus. At detection of oestrus, gilts were inseminated with 3 x 10(9) live sperm, either fresh (FS; n = 13), FT (n = 10), or FT supplemented with 10% v/v SP (n = 12). Gilts were killed 8 h later, their reproductive tracts recovered and the uterotubal junctions (UTJs) flushed to recover sperm. Fewer (p < 0.01) sperm were recovered following FT, compared to FS, inseminations, and there was no evident effect of SP. In Experiment two, 30 pre-pubertal gilts received IM injections of 1000 IU eCG followed by 5 mg pLH 80 h later to control time of ovulation. Gilts were inseminated with 3 x 10(9) live FS sperm (n = 6), FT sperm (n = 15) or FT sperm plus 10% SP (n = 9) at 12 h before ovulation and then sacrificed 8 h later. The UTJs were dissected and flushed for sperm recovery. Fewest (p < 0.001) sperm were recovered following FT insemination and there was no evident effect of SP. These data demonstrate that the size of the sperm reservoir is markedly reduced in gilts inseminated with FT sperm. However, the lack of effect of SP suggested that either it did not reverse cryocapacitation or that such a reversal does not impact the in vivo ability to create a sperm reservoir.  相似文献   
39.
Objective To determine the effect of a long-acting local anaesthetic on the plasma cortisol response in calves dehorned using a scoop.
Design A physiological study with controls.
Procedure Seventy female calves, 3 to 4 months old, were divided into seven groups and dehorned by scoop with or without a long acting local anaesthetic (bupivacaine) which provides local anaesthesia for 3 to 4 h. In some treatment groups the local anaesthetic was given a second time, after 4 h, to give 8 h of anaesthesia. Blood samples were taken before and for 9 h after treatment and plasma cortisol concentrations were measured.
Results Scoop dehorning caused a marked rise in plasma cortisol concentration, which returned to pre-dehorning values after 7 h. The cortisol concentrations of calves given bupiva-caine were similar to those of control animals for 4 h after dehorning, but then a significant and protracted rise occurred, with concentrations returning to pretreatment values at about 9 h after dehorning. In calves given a second treatment of bupivacaine 4 h after dehorning, the plasma cortisol concentration remained similar to control values for 8 h after dehorning but then increased sharply.
Conclusions During its period of activity long-acting local anaesthetic prevented the rise usually seen after scoop dehorning in plasma cortisol concentrations; by inference it also alleviated the pain-induced distress caused by this procedure. However, when its effects had worn off the plasma cortisol values rose sharply indicating that animals still experienced pain-induced distress despite local anaesthetic being administered.  相似文献   
40.
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