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1.
The object of this investigation was to estimate the peripheral plasma levels of estradiol-17beta and progesterone and the consistency of the cervix by rectal palpation of sows before, during and after post-weaning estrus. The tonicity of the cervix increased from approximately 4 days before the onset of heat, became firmest during estrus, and became softer again during the post-estrual period. The levels of estradiol increased before the onset of heat and reached maximum levels on the day preceding heat, then decreased to baseline. The progesterone levels remained low until post-estrus, then increased rapidly. One sow which did not come in heat constantly had a soft cervix and low hormone levels. It is concluded that estrogen might be implicated in the increased tonicity of the cervix and that rectal examination of the cervix provides valuable information on ovarian function. 相似文献
2.
The antihypertensive effect of atenolol, a new beta-1-receptor blocking agent, was studied in a double-blind trial in which 45 patients with essential hypertension were randomly assigned to placebo or atenolol treatment. Atenolol caused a statistically significant and clinically relevant reduction of blood pressure. The optimum daily dose for moderately severe hypertension was considered to be 200 mg. Several irrelevant side effects were collected by the use of a check list, but there was no difference in the number of complaints during placebo and active treatment. Atenolol has a useful antihypertensive effect and, at least theoretically, has advantages over other beta-adrenergic blocking agents. 相似文献
3.
In this study a method for the analysis of simultaneous multiple measurements of kinematics and stabilizing forces related to human postural dynamics is proposed. Each subject in a group of normal subjects (n=10) was tested with eyes-open and eyes-closed with simultaneous but uncorrelated vestibular and proprioceptive stimuli in order to investigate the contributions of individual sensory feedback loops. Statistical analysis was made by means of multi-input multi-output identification of a transfer function from stimuli to stabilizing forces of the feet and the resulting body position, the transfer function being compatible with a biomechanical model formulated as a stabilized segmented inverted pendulum subject to feedback of body sway and position. Each individual model estimated is effective in predicting a subject's response to new stimuli and in describing the interacting effects of stimuli on body kinetics. The proposed methodology responds to the current needs of data analysis of multi-stimulus multi-response experiments. 相似文献
4.
In a retrospective study, based on data from the national litter recording system, farrowing rate and litter size of sows served (inseminated or mated) during the lactation period (n = 574) or after a lactation period shorter than 28 days (n = 14,219) were analysed. The results were compared with the corresponding figures for sows with lactation length between 28 and 35 days and weaning to first service interval of 4 or 5 days (reference group; n = 41,741). The farrowing rate of the reference group was 80.9% and subsequent litter size was 13.7 total piglets born. Among sows served prior to weaning, the farrowing rates and litter sizes were significantly lower for those served earlier than 22 days post-farrowing compared to those served later (P < 0.05). Shorter lactations than 28 days and service within 10 days post-weaning led to lower farrowing rates than in the reference group (P < 0.01). Significant differences were seen after different lactation lengths. After correction for weaning to service interval, preceding litter size weaned, parity, breed and the interaction between parity and breed, litter size was significantly and positively associated with the preceding lactation length. The study shows that service within the first 3 weeks post-farrowing results in reduced reproductive performance. 相似文献
5.
Joanna Olsson Bo Karlberg Krister Kristensson Fredrik berg 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,707(1-2)
A method for determination of malondialdehyde with capillary electrophoresis using UV detection at 267 nm has been developed. The buffer system consisted of 10 mM borax and 0.5 mM CTAB at pH 9.3. Malondialdehyde migrated as the first peak in the electropherogram at 2.6 min. Limit of detection was 1.2 μM corresponding to 7.8 pg. Malondialdehyde was determined before and after stimulating lipid peroxidation with the addition of ferrous ammonium sulphate to homogenates of rat brain tissue. Proteins were precipitated by boiling and removed from the brain homogenates with centrifugation. No further pretreatment was made before injecting the homogenates on the CE system. Non-precipitated homogenates could also be analyzed, but this required washing of the capillary with 0.1 M NaOH before introduction of the next sample. 相似文献
6.
Integrative analysis for finding genes and networks involved in diabetes and other complex diseases 下载免费PDF全文
Bergholdt R Størling ZM Lage K Karlberg EO Olason PI Aalund M Nerup J Brunak S Workman CT Pociot F 《Genome biology》2007,8(11):R253
We have developed an integrative analysis method combining genetic interactions, identified using type 1 diabetes genome scan data, and a high-confidence human protein interaction network. Resulting networks were ranked by the significance of the enrichment of proteins from interacting regions. We identified a number of new protein network modules and novel candidate genes/proteins for type 1 diabetes. We propose this type of integrative analysis as a general method for the elucidation of genes and networks involved in diabetes and other complex diseases. 相似文献
7.
Helena J Bailes Wayne L Davies Ann EO Trezise Shaun P Collin 《BMC evolutionary biology》2007,7(1):200
Background
One of the greatest challenges facing the early land vertebrates was the need to effectively interpret a terrestrial environment. Interpretation was based on ocular adaptations evolved for an aquatic environment millions of years earlier. The Australian lungfish Neoceratodus forsteri is thought to be the closest living relative to the first terrestrial vertebrate, and yet nothing is known about the visual pigments present in lungfish or the early tetrapods. 相似文献8.
9.
Bohnstedt KC Karlberg B Basun H Schmidt S 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,827(1):39-43
F2-isoprostanes are produced by the non-enzymatic peroxidation of arachidonic acid in membrane phospholipids. This paper describes a new method for the determination of all four classes of F2-isoprostanes in human cerebrospinal fluid (CSF) involving separation on a 1 mm x 150 mm porous graphitic carbon (PGC) column and detection by triple quadrupole mass spectrometry in negative-ion electrospray mode. The sample pre-treatment consisted of an ultrafiltration step, following which 300 microl of CSF sample could be injected directly onto a 1 mm x 10 mm PGC guard column functioning as a trap for the analytes. The loading solvent was Milli-Q water at 125 microl/min. After 3 min, the sample was switched into the separation column. The F2-isoprostanes were separated in 20 min using a linear solvent gradient comprising water, methanol, acetonitrile and ammonium hydroxide at a pH of 9.5 and a flow of 50 microl/min The limit of detection (calculated as 3S/N) was approximately 40 pM (14 pg/ml). The assay was linear within the examined range (18-450 pg/ml), using CSF spiked with iPF2alpha-III standard (r(2)>0.995). Repeatability data were calculated for CSF spiked to 90 pg/ml and the relative standard deviation (RSD) obtained was 3% (n=6). 相似文献
10.
Pregnancy associated glycoproteins (PAG) in postpartum cows, ewes, goats and their offspring 总被引:1,自引:0,他引:1
Determination of plasma concentrations of pregnancy associated glycoproteins (PAG) has been used for early pregnancy diagnosis in cows. However, this is complicated by the presence of PAG in plasma for an extended period postpartum. The main objective of the present study was to investigate the postpartum elimination rates of pregnancy associated glycoproteins (PAG) in sheep, goats and cows in order to gain background information applicable to the use of PAG for pregnancy diagnosis in domestic ruminants. A second objective was to investigate whether PAG are transferred to the foetus and newborn, by measuring plasma PAG concentrations in calves, lambs and goat kids before and after colostrum feeding. PAG in the blood at parturition were eliminated by a first order process in the cows and ewes, while a two-step log-linear decline occurred in the goats. Estimated postpartum half-life of plasma PAG in the cows and ewes was 9 and 4.5 days, respectively. In the goats, half-lives were 3.6 and 7.5 days in the initial fast and terminal slow phase. Basal levels were reached 80-90 days postpartum in cows. Plasma PAG concentration can be used for pregnancy diagnosis from day 28 after AI, provided that the time interval from calving to AI is >60 days. Using a heterologous antibody RIA, we found 4 ng/mL to be the appropriate cut-off. Due to the presence of PAG residues from the previous gestation, the interval from AI to pregnancy diagnosis should increase by approximately 0.5 days beyond 28 days for each day of AI closer to calving than 60. Measurements in newborn ruminants suggested that PAG enter the foetal blood in utero and that colostral PAG are transferred to the newborn. Following the peak plasma concentration observed 1 day after birth in most of the animals, PAG were rapidly eliminated in a log-linear fashion. 相似文献