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61.
62.
In vitro anaerobic incubations were used to determine the effect of different oils (LO-linseed, SO-sunflower, FO-fish oil) on trans fatty acid production in rumen fluid and to test if combining of monensin (MON) with the oils affects the interactions on trans fatty acid concentrations in mixed cultures of ruminal microorganisms. Two different sources of rumen fluid were used; the inoculum from the sheep fed hay and barley (80:20%)--the inoculum A and the inoculum from the sheep fed alfalfa and barley (80:20 %)--the inoculum B. The analyses showed that inoculum B contained more short chain fatty acids (SCFA), medium chain fatty acids (MCFA) and saturated fatty acids (SFA) than inoculum A. In contrast, inoculum A contained more unsaturated fatty acids (UFA) than inoculum B. The results show, that the oils affected the biohydrogenation of fatty acids (FA) by increasing the concentration of C18:0 (3-7 times) and trans C18:1 isomers (2-9 times). The concentration of two main intermediates of FA biohydrogenation-- cis 9, trans 11 C18:2 (CLA) and trans 11C18:1 (TVA) were increased with the oils, but FO was more efficient than other plant oils on CLA and TVA production.The monensin treatment had similar effect on FA metabolism as the oil treatment in comparison to unincubated control. The interactions of monensin treatment with the oils were characterized with decrease (LO+MON, SO+MON) or increase (FO+MON) of the proportions of C18:0 and trans C18:1 isomers in comparison to oil treatment.The highest concentrations of two main isomers--CLA,TVA were found in the samples containing fish oil and monensin. In conclusion, fish oil treatment and monensin with fish oil treatment was more efficient than other plant oils in the effect on trans fatty acid production (mainly CLA and TVA) in fermentation fluid in vitro.  相似文献   
63.
Acute onset convulsive disorders in the canine may result from exposure to a variety of toxicants including strychnine, insecticides, metaldehyde, zinc phosphide, methylxanthines, drugs of abuse, bromethalin, and the tremorgenic mycotoxins (roquefortine and penitrem A). Although several of the above can be identified in a single gas chromatography-mass spectrometry (GC-MS) screen most have to be determined by separate tests. This report describes a modification of the strychnine extraction procedure, which allows thin layer chromatographic (TLC) identification of strychnine, bromethalin, roquefortine, and penitrem A in suspect baits, stomach contents or vomitus, and extends the identification to a wide variety of drugs, pesticides, and environmental contaminants by GC-MS. Samples were mixed with base, extracted into CH2Cl2 and the organic fraction back-extracted with acid. The organic fraction (neutrals) was purified by gel permeation chromatography (GPC) and analyzed by TLC to determine penitrem A and bromethalin. The acidic aqueous fraction was adjusted to pH > 9 and extracted into CH2Cl2. The resulting CH2Cl2 layer (bases) was then analyzed by TLC to determine strychnine and roquefortine. The organic basic and neutral fractions were recombined with a late eluting GPC fraction and analyzed by GC-MS. Of 312 samples analyzed by TLC from 1995 to 2001, 35 were positive for strychnine alone, 58 were positive for both roquefortine and penitrem A, 4 were positive for roquefortine alone, and 1 was positive for bromethalin. None of the samples were positive for penitrem A alone. Samples negative by TLC were analyzed by the GC-MS extended procedure since mid-1999, and 14 have shown positive for a wide variety of compounds with convulsant activity.  相似文献   
64.
The objective of the study was to demonstrate the presence of estrogen receptor alpha (ERalpha) and beta (ERbeta) protein and corresponding mRNA in porcine ovarian follicles and corpora lutea obtained on day 10, 18, 32, 50, 71 and 90 post coitum (p.c.) using immunohistochemistry, Western blot, and RT-PCR analysis. Immunohistochemistry showed that ERalpha protein was located in the granulosa cells of ovarian follicles and the strongest immunoreaction was observed on days 32 and 50 p.c. The ERbeta protein was found mainly in theca cells of follicles as well as in luteal cells. The most intense immunoreaction was observed on day 18 p.c. within theca cells, while in the corpus luteum (CL) the intensity of ERbeta staining gradually increased and remained elevated at mid and late pregnancy. In CL by day 50 p.c. immunoreaction for ERbeta was present only in small luteal cells, but starting from day 71 to 90 p.c. it was observed in both small and large luteal cells. Western blot analysis was performed and validated data obtained from immunohistochemistry. RT-PCR results indicated that ERalpha mRNA was expressed only in ovarian follicles of the pregnant swine, while that of ERbeta in both follicles and CL. The results suggest an autocrine/paracrine role of estrogens acting via both ERalpha and ERbeta in the regulation of the ovarian function during pregnancy and for the process of successful reproduction.  相似文献   
65.
Phosphono peptides exhibited plant-growth-regulating activity when tested on Lepidium sativum and Cucumis sativus. The studies have provided evidence that the mechanism of action of these compounds may involve the uptake of the phosphono peptides into the plant, intracellular hydrolysis of the peptide bond and release of the P-terminal aminoalkylphosphonic acid. This acid or its metabolite is then probably responsible for the observed physiological effect.  相似文献   
66.
OBJECTIVE: To evaluate a modified posterior rhinomanometric method for clinical application in dogs. ANIMALS: 15 healthy Beagles and 8 Bulldogs (4 healthy and 4 with respiratory problems). PROCEDURES: Rhinomanometry was performed 3 times within a 15-minute period in anesthetized dogs.Transnasal pressure (P(NA)) and nasal resistance (R(NA)) were determined by use of artificial airflow (adjusted for body weight) for inspiration (P(NAin) and R(NAin), respectively) and expiration (P(NAout) and R(NAout)). Procedures were repeated for the Beagles 7 days later. RESULTS: For the Beagles, mean +/- SD of P(NAin) for both days (0.162 +/- 0.042 kPa) was significantly lower than P(NAout) (0.183 +/- 0.053 kPa). Similarly, R(NAin) (1.47 +/- 0.41 kPa/[L/s]) was significantly lower than R(NAout) (1.64 +/- 0.46 kPa/[L/s]). Pairwise comparison of values for P(NA) and R(NA) for the 2 days revealed no significant difference. Repeatability of the method (estimated as within-day variation) for R(NA) was +/- 0.19 kPa/(L/s), whereas variation between the days was +/- 0.36 kPa/(L/s) for R(NAin) and +/- 0.44 kPa/(L/s) for R(NAout). The 4 clinically normal Bulldogs had R(NA) values ranging from 1.69 to 3.48 kPa/(L/s), whereas in the 4 Bulldogs with respiratory problems, R(NA) ranged from 9.83 to 20.27 kPa/(L/s). CONCLUSIONS AND CLINICAL RELEVANCE: R(NA) is inversely dependent on body size and nonlinearly associated with airflow. We propose that R(NA) in dogs should be determined for airflows standardized on the basis of body size. The P(NA) and R(NA) in Beagles can be measured with sufficient repeatability for clinical use and nasal obstructions are detectable.  相似文献   
67.
OBJECTIVE: To assess the effects of repeated episodes of propofol-associated anesthesia on quality of recovery from anesthesia, clinical status, and erythrocyte physiology in cats. DESIGN: Original study. ANIMALS: 37 cats undergoing short-duration anesthesia for radiotherapy. PROCEDURES: Twice daily on 5 consecutive days, 13 cats with squamous cell carcinoma of the nasal planum (group 1) underwent anesthesia: first via administration of propofol or a midazolam (0.2 mg/kg [0.09 mg/lb])-propofol combination and then via administration of ketamine and midazolam each day (latter data were not analyzed). During a 19-day period, 24 cats with vaccine associated sarcoma (group 2) were anesthetized 12 times with propofol or a midazolam-propofol combination. Anesthesia was maintained with propofol in both groups. Hematologic analysis was performed before, during, and on completion of radiotherapy; changes in Hct and hemoglobin concentration between groups were compared. RESULTS: Mean duration of anesthesia was 8.1 minutes (range, 5 to 20 minutes); no adverse events were detected during recovery. Total dose of propofol administered did not differ between groups 1 (6.34 mg/kg [2.88 mg/lb]) and 2 (4.71 mg/kg [2.14 mg/lb]). Midazolam administration decreased the propofol dose by 26%. Overall decreases from baseline in Hct and hemoglobin concentration were not significantly different between the 2 groups, nor clinically important; however, compared with baseline, values in group 2 were significantly lower after 6 and 12 anesthetic episodes for both protocols. Heinz bodies were identified in low numbers in both groups during radiotherapy. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that repeated propofol-associated short-duration anesthesia does not lead to clinically relevant hematologic changes in cats undergoing short-duration radiotherapy.  相似文献   
68.
Recent observations in seasonal-breeding mammals indicate that the hypothalamus is programmed to become leptin resistant during long days (LD) and leptin sensitive during short days (SD). These observations support the possibility that photoperiod mediates at least part of its effects on melatonin secretion through changes in leptin sensitivity. Herein we examined the interaction of season and recombinant ovine leptin (oleptin) on melatonin secretion by pineal explants in short-term culture. Glands were collected after sunset from eight ewes during LD (March, April, May, June) and from an additional eight ewes during SD (September, October, November, December). Glands were transected saggitally and coronally into quarters, with each equilibrated in 2.5ml of DMEM for 120min, followed by a 3h incubation in medium containing either 0 or 50ng/ml of oleptin. Treatment with oleptin reduced (P<0.001) melatonin secretion compared to controls during LD by approximately 22% at 2, 2.5 and 3h of culture. However, in cultures from glands collected during SD, oleptin stimulated (P<0.078) melatonin secretion approximately 50% compared to control. These effects were consistent throughout each respective season. We conclude that the secretion of melatonin from the ovine pineal gland is negatively responsive to leptin during LD, whereas leptin may stimulate melatonin secretion during SD.  相似文献   
69.
Although brook trout and the Arctic char hybrids are able to reproduce, individuals with decreased fertility or even fish that are unable to produce any gametes have been also described. Abnormal gonadal development and disturbances in the gamete production in the char hybrid offspring may be triggered by the odd chromosome number and disturbances in their pairing during meiosis. To verify this hypothesis, cytogenetic examination and the gonadal histology analysis of the brook trout x Arctic char hybrids were carried out. Diploid chromosome number in the studied char (F1) hybrids varied from 82 to 84 (FN = 99–102). Among 28 hybrids, 12 males, three females, nine intersex individuals and two sterile specimens were described. In the case of two individuals, gonads were not found. Diploid chromosome numbers in the males and intersex individuals varied from 82 to 84. Chromosome numbers in the females were 82 and 83 chromosomes. Two sterile fish exhibited karyotypes composed of 82 and 84 chromosomes. Predominance of the ovarian component in the intersex gonads and gonadal sex ratio distortion towards the males suggested hybrid females had problems with gonadal differentiation. However, the lack of the clear relationship between chromosome number and gonadal development in the studied hybrids did not support our hypothesis that odd chromosome number may be responsible for such reproductive disturbances in the hybrid individuals. We have presumed that sterility and intersexual development of the gonads may be caused by interactions between brook trout and Arctic char genes on the sex chromosomes and autosomes rather than unpairing of the parental chromosomes.  相似文献   
70.
利用油菜花瓣实验检测油菜菌核病   总被引:4,自引:0,他引:4  
摘要:油菜菌核病是由Sclerotinia sclerotiorum (Lib) de Bary引起的,是世界范围内造成损失最严重的病害之一。该病害主要通过感染了核盘菌子囊孢子的花瓣落在植株茎、叶上来侵染植株。本实验采用添加了两种不同PH指示剂的改良型Steadman’s培养基检测被子囊孢子感染的花瓣,样品采自合肥的两块不同试验田,在油菜花期(3月下旬~4月中旬)每天采摘新鲜花瓣在室温下培养,结果表明整个花期,除1块田1天没有检测出外,其余每天都有被子囊孢子感染的花瓣出现(感染子囊孢子的花瓣接种后培养基变色)。油菜初花期被子囊孢子感染的花瓣较少,而盛花期和终花期被感染的花瓣较多,第一块田被感染的花瓣数在两种培养基上出现的百分率分别为32.0%和40.2%,第二块田分别为27.3%和35.7%。第一块田油菜菌核病的发病率和病指分别为2.7%和1.8,第二块田分别为1.5%和0.4。子囊孢子感染的花瓣数与后期油菜菌核病的发病率呈显著正相关(r=0.829,r0.05=0.811)。研究被感染的花瓣数可以帮助决定最适宜的病害防治时期。  相似文献   
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