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81.
Two pony mares were immunized against recombinant porcine inhibin alpha subunit three times with 39 day intervals. Clinical findings and endocrinological changes before immunization were taken as the control. The first significant rise in the anti-inhibin titre (P<0.05) in the circulation was found 27 days after the first injection. Maximum binding activity was reached by the 12th day after the second booster dose. The number of small, medium and large sized follicles had increased significantly compared to before immunization (11.75 +/- 4.30, 2.75 +/- 0.69 and 2.51 +/- 0.63 vs 6.50 +/- 1.43, 1.83 +/- 0.44 and 1.33 +/- 0.38, respectively), but the ovulation rate remained unchanged after immunization. The average plasma concentration of FSH and estradiol-17beta during the estrous cycle increased significantly (P<0.05) after immunization. These results suggest that immunization against inhibin is a useful tool to increase the number of ovarian follicles during the estrous cycle of pony mares. Moreover, the present study supported the concept that inhibin plays a major role in the control of follicular growth through its inhibitory effect on FSH secretion synergistically with steroid hormones.  相似文献   
82.
Hepatocyte growth factor (HGF) is a pleiotropic cytokine that stimulates a wide array of cellular targets, including hepatocytes and other epithelial cells, melanocytes, endothelial and hematopoietic cells. We have cloned a different form of cDNA, with a deletion of 15 base pairs predicted to result in the loss of 5 amino acids from the first kringle domain. To investigate the biological activity, original and deleted variant of feline HGF cDNAs were transiently expressed in COS-7 cells. Both recombinant feline HGFs showed almost the same dose-response curves in the stimulation of the growth of BNL CL.2 cells (a mouse hepatocyte cell line) and scatter activity of Madin-Darby canine kidney (MDCK) cells. The findings reported here suggest that the deleted variant of feline HGF has almost the same biological activity as the original in terms of the proliferation and scatter activity.  相似文献   
83.
OBJECTIVE: To evaluate the efficiency of four warming procedures, introduced after anaesthetic induction and continued during surgery, in minimising heat loss in anaesthetised dogs. DESIGN: Dogs were paired. One of each pair was a control; the other was subjected to one of four warming procedures. METHODS: Ninety-six dogs were involved in total. Pairs of dogs were matched for breed, hair length, and type of surgical procedure and placed adjacent to each other in a large temperature-controlled surgical theatre. One dog within each pair was assigned to one of four warming procedures that commenced immediately after anaesthetic induction. Group 1 (11 pairs) were placed on a purpose-designed prewarmed (41 degrees C) electrically heated pad. Group 2 (18 pairs) were placed on a prewarmed electric heat pad (41 degrees C), cocooned by four wrapped water bottles (initially 41 degrees C) and subjected to radiant heat (150 watt lamp placed 50 cm away from the head of the dog). Group 3 (11 pairs) were surrounded by a forced air warming mattress (set at 43 degrees C). Group 4 (8 pairs) were connected via the anaesthetic breathing circuit to a heater/humidifier (set at 41 degrees C). Rectal temperature measurements were recorded every 15 min for the first 3 h of anaesthesia. The fall in rectal temperature of the control dog was subtracted from the fall in temperature of the treatment dog and this measurement was used to assess the efficacy of the various warming procedures. RESULTS: The mean rectal temperature of unheated 'control' dogs decreased 1.9 +/- 0.6, 1.4 +/- 0.4 and 1.1 +/- 0.4 degrees C over the first, second and third hour respectively. After 3 h the temperature fall differential for all groups were 0.7 +/- 0.7 (Group 1), 3.1 +/- 1.1 (Group 2), 2.4 +/- 1.1 (Group 3) and 1.0 +/- 1.1 degrees C (Group 4). Thus the group 2 procedure was the most successful in preventing a drop of temperature followed by groups 3, 4 and 1. CONCLUSION: Large dogs undergo significant reduction in core body temperature especially during the first 2 h of anaesthesia and surgery. Supplementary warming substantially reduces this fall in body temperature, although certain warming procedures were found to be more effective than others.  相似文献   
84.
The current success rate of cloned mice from adult somatic cell nuclei is very low, whereas it is relatively high for cloned mice from ES cell nuclei. In this experiment, we examined whether the success rate of cloning from somatic cells could be improved via nuclear transfer embryonic stem cells (ntES cells) established from somatic cell nuclei. We obtained 11 cloned mice and 68 ntES cell lines from the somatic cell nuclei of 7 mice, and cloned 41 mice were cloned from the ntES cell nuclei. Unexpectedly, the overall success rate of cloning from ntES cell nuclei in this series was no better than when using somatic cell nuclei. Interestingly, full-term cloned mice were produced only via ntES cells from two individuals, but not by direct nuclear transfer from the somatic cells, and vice versa. Ultimately, we were able to obtain clone mice from 6 out of 7 individuals using either somatic cells or ntES cells. Thus, although ntES cells as donor nuclei do not absolutely assure a better success rate for mouse cloning than somatic cells, to preserve and clone valuable individuals, we recommend that ntES cell lines be established. These can then be used as an unlimited source of donor nuclei for nuclear transfer, and thus complement conventional somatic cell nuclear transfer cloning approaches.  相似文献   
85.
OBJECTIVE: To measure cardiac output in healthy female anesthetized dogs by use of lithium dilution cardiac output and determine whether changes in mean arterial pressure were caused by changes in cardiac output or systemic vascular resistance. DESIGN: Prospective clinical study. ANIMALS: 20 healthy female dogs. PROCEDURE: Dogs were anesthetized for ovariohysterectomy. Ten dogs breathed spontaneously throughout anesthesia, and 10 dogs received intermittent positive-pressure ventilation. Cardiovascular and respiratory measurements, including lithium dilution cardiac output, were performed during anesthesia and surgery. RESULTS: Mean arterial pressure and systemic vascular resistance index were low after induction of anesthesia and just prior to surgery and increased significantly after surgery began. Cardiac index (cardiac output indexed to body surface area) did not change significantly throughout anesthesia and surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Results provide baseline data for cardiac output and cardiac index measurements during clinical anesthesia and surgery in dogs. Changes in mean arterial pressure do not necessarily reflect corresponding changes in cardiac index.  相似文献   
86.
An inhalational technique for rapid induction of anaesthesia in unsedated cats using sevoflurane and nitrous oxide is described. Using a pliable, tight-fitting, face mask, sevoflurane (7.5-8%) was delivered from an out-of-circuit precision vaporiser connected to a coaxial non-rebreathing system using a fresh gas flow of 1 l oxygen and 2 l nitrous oxide per min. Cats were restrained with gentle but firm pressure applied by scruffing the dorsal cervical skin until the righting reflex was lost and the patient could be positioned in lateral recumbency. Typically, cats could be positioned on their side in a light plane of anaesthesia within 1 min of applying the mask, at which time the sevoflurane concentration was reduced to 5% or less. A similar protocol, using a lower initial concentration of sevoflurane, is recommended for old or debilitated patients. Maintenance of light sevoflurane (2-4%) anaesthesia by mask permitted minor interventions to be performed readily, including blood collection, intravenous chemotherapy, abdominal palpation, radiography and ultrasonography. More painful procedures, such as bone marrow aspiration, required a deeper plane of anaesthesia. Cats were sufficiently deep to be intubated, if this was required, about 3 min after commencing the induction. Recovery from sevoflurane/nitrous oxide anaesthesia was smooth and rapid, with most cats being able to right within 5 min of discontinuing the agents. This protocol for rapid inhalational induction and recovery is particularly suited to feline practice, where rendering an uncooperative patient unconscious greatly facilitates the completion of many minor diagnostic and therapeutic procedures, especially when these must be performed on successive days or when peripheral vascular access is limited. For longer procedures, isoflurane may be substituted for sevoflurane for maintenance of anaesthesia in order to minimise cost.  相似文献   
87.
Most juveniles of Haliotis discus hannai have been found to be descendants of wild individuals, although most adults were artificially produced (released) individuals as a result of restocking inside the refugium located near the head of Oshoro Bay, Hokkaido, Japan. To estimate the larval supply from released and wild individuals into the refugium and to compare the suitability of locations as larval sources, we simulated larval dispersal using a coupled hydrodynamic and particle-tracking model. The simulation results indicated that more larvae may be supplied from the wild adults inside the bay to the refugium than from the released adults. These results are consistent with the observed high abundance of wild juveniles in the refugium. Most larvae from the refugium were predicted to disperse out of the bay. We found that larval retention in the bay was at least one order of magnitude higher than that in the refugium. Thus, it may be more effective in terms of self-replenishment and reproduction if the refugium were to be expanded to the bay scale. There were only minor differences among the compared sites at the head of the bay in terms of their suitability as larval sources. Consequently, the establishment of new refugia in this area could be expected to provide an effectiveness equal to that of the current refugium.  相似文献   
88.
Isono  Chiaki  Maruta  Hitomi  Ma  Yun  Ganeko  Natsuki  Miyake  Tsuyoshi  Yamashita  Hiromi 《Fisheries Science》2020,86(6):1087-1099
Fisheries Science - The proximate composition and nutritional content of oysters define their quality and commercial value. Cultivation site and harvest date may impact these characteristics. We...  相似文献   
89.
The aim of this study was to characterize ir-IGF-I pattern and its relation to other hormones during the oestrous cycle in mares. Nine non-pregnant non-lactating pluriparous thoroughbred mares were used. The studied mares were examined ultrasonically and bled daily to follow the ovarian changes and the hormonal milieu for a complete Interovulatory interval (IOI). Two (minor and major) follicular waves were characterized per IOI in thoroughbred mares. The largest follicle of the first follicular wave (DF1) was firstly detected at D - 1.75 ± 0.47 with a growth rate of 2.78 ± 0.14mm/day and maximum diameter of 22.45 ± 0.75mm on day 6.65 ± 0.82. The largest follicle of the second follicular wave (DF2) had a growth rate of 2.15 ± 0.29 mm/day, reached a maximum diameter of 42.70 ± 2.63 mm on D 19.25 ± 0.43. Ir-IGF-I increased significantly prior to ovulation and had a similar pattern to oestrogen (r = 0.84, p < 0.05), suggesting that the ovarian follicles are the main source of circulating ir-IGF-I during the oestrous cycle of mares and that ir-IGF-I may be a crucial factor in follicular differentiation and maturation. In conclusion, this study demonstrated that ir-IGF-I is secreted during the oestrous phase of the cycle concomitant with the development of the future ovulatory dominant follicle, and it may act in synergy with other hormones for the selection and differentiation of the dominant follicle.  相似文献   
90.
Endotoxic lipopolysaccharide (LPS) with potent immunostimulatory activity is recognized by the receptor complex of MD-2 and Toll-like receptor 4. Crystal structures of human MD-2 and its complex with the antiendotoxic tetra-acylated lipid A core of LPS have been determined at 2.0 and 2.2 angstrom resolutions, respectively. MD-2 shows a deep hydrophobic cavity sandwiched by two beta sheets, in which four acyl chains of the ligand are fully confined. The phosphorylated glucosamine moieties are located at the entrance to the cavity. These structures suggest that MD-2 plays a principal role in endotoxin recognition and provide a basis for antiseptic drug development.  相似文献   
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