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1.
Hradecký P 《Theriogenology》1983,20(4):491-498
Uteri of 69 African antelopes and a giraffe were morphologically examined and numbers of caruncles and their rows in each horn were recorded. Antelopes of subfamilies Taurotraginae, Aepycerotinae, Antilopinae, and Alcelaphinae had about 50 to 100 caruncles arranged in four rows in each uterine horn. Hippotraginae had about 100 to 200 caruncles in six to eight rows in each horn, and Reduncinae had about 10 to 20 caruncles in two rows in each uterine horn. The giraffe had about 70 caruncles arranged in four rows in each uterine horn. Uterine caruncles in some antelopes had specific features such as pigmentation of apices, caruncles on stems, and caruncles with honeycomb structure. 相似文献
2.
On Day 5 of pregnancy, before the blastocyst migrates to the uterus, one uterine horn was ligated to restrict the trophoblast to the lumen ipsilateral to the corpus luteum. The numbers of placentomes (caruncles and cotyledons) were reduced by half, but neither at 120 nor at 140 days of pregnancy (term 147 days) did the weights of placentae and fetuses of treated ewes differ significantly from those of control ewes. Amongst uterus-ligated animals prepared for chronic study, the rate of uterine blood flow (electromagnetic flow transducer, ml/min) to the pregnant horn was higher than in control ewes, as was the concentration of progestagens in maternal peripheral blood. There may be a compensatory response that causes hypertrophy of placentomes and that increases blood flow to the uterine horn containing placental tissue. 相似文献
3.
The influence of nutritional protein during the first and second trimesters of pregnancy on placental measures at term and caruncle numbers in the uteri of adult offspring was determined in composite beef heifers. At artificial insemination (AI), heifers were divided by weight and composite genotype into four dietary treatment groups, identified by the level of protein components fed during the first and second trimesters: high/high (HH), high/low (HL), low/high (LH), low/low (LL). Expelled placentas were collected and weighed, and cotyledons were dissected, counted, weighed, and measured. Uteri from mature female offspring were dissected at slaughter and caruncles counted. The number of cotyledons in the expelled placenta was increased by high dietary protein in the second trimester (P = 0.02) and varied with genotype (P = 0.03). Placental weight was influenced by maternal undernutrition during early gestation dependent on dam genotype (P = 0.001). Placental efficiency, as determined by calf weight:placental weight, increased with dam age (P = 0.03). Calf birth weight was closely associated with placental weight (P = 0.002) and cotyledonary weight (P = 0.001) and surface area (P = 0.04), but not with the number of cotyledons. Leptin concentrations during early (R = -0.29) and late gestation (R = -0.25) correlated with placental weight, and Insulin-like growth factor binding proteins throughout gestation correlated with the number of cotyledons (R = -0.28 to-0.33). The number of uterine caruncles in the nonpregnant adult offspring did not correlate with the dam's genotype, nutrition treatment, or cotyledon number in the expelled placenta. 相似文献
4.
The objective of this study was to determine the effects of in vitro embryo production on angiogenesis and morphometry of the bovine placenta during late gestation. Blastocysts produced in vivo were recovered from superovulated Holstein cows. Blastocysts produced in vitro were obtained after culture of in vitro-matured and -fertilized Holstein oocytes. Single blastocysts from each production system were transferred into heifers. Fetuses and placentas were recovered on Day 222 of gestation (in vivo, n=12; in vitro, n=12). Cotyledonary and caruncular tissues were obtained for quantification of vascular endothelial growth factor (VEGF) and peroxisome proliferator-activated receptor-gamma (PPARgamma) mRNA and protein. Tissue sections of placentomes were prepared for morphometric analysis. Fetuses and placentas were heavier from embryos produced in vitro than from embryos produced in vivo. More placentas from embryos produced in vitro had an excessive volume of placental fluid. There was no effect of treatment on the expression of mRNA for VEGF and PPARgamma in either cotyledonary or caruncular tissues. The expression of VEGF protein in cotyledons and caruncles as well as the expression of PPARgamma protein in cotyledons were not different between the in vitro and in vivo groups. However, caruncles from the in vitro group had increased expression of PPARgamma protein. The total surface area of endometrium was greater for the in vitro group compared with controls. In contrast, the percentage placentome surface area was decreased in the in vitro group. Fetal villi and binucleate cell volume densities were decreased in placentomes from embryos produced in vitro. The proportional tissue volume of blood vessels in the maternal caruncles was increased in the in vitro group. Furthermore, the ratios of blood vessel volume density-to-placentome surface area were increased in the in vitro group. In conclusion, these findings are consistent with the concept that compensatory mechanisms exist in the vascular beds of placentas from bovine embryos produced in vitro. 相似文献
5.
Some members of the gamma herpesvirus genus Macavirus are maintained in nature as subclinical infections in well-adapted ungulate hosts. Transmission of these viruses to poorly adapted hosts, such as American bison and cattle, can result in the frequently fatal disease malignant catarrhal fever (MCF). Based on phylogenetic analysis, the MCF viruses (MCFV) cluster into two subgroups corresponding to the reservoir hosts’ subfamilies: Alcelaphinae/Hippotraginae and Caprinae. Antibody cross-reactivity among MCFVs has been demonstrated using techniques such as enzyme linked immunosorbent and immunofluorescence assays. However, minimal information is available as to whether virus neutralizing antibodies generated against one MCFV cross react with other members of the genus. This study tested the neutralizing activity of serum and plasma from select MCFV-infected reservoir hosts against alcelaphine herpesvirus 1 (AlHV-1) and ovine herpesvirus 2 (OvHV-2). Neutralizing antibody activity against AlHV-1 was detected in samples from infected hosts in the Alcelaphinae and Hippotraginae subfamilies, but not from hosts in the Caprinae subfamily. OvHV-2 neutralizing activity was demonstrated in samples from goats (Caprinae) but not from wildebeest (Alcelaphinae). These results show that neutralizing antibody cross reactivity is present to MCFVs within a virus subgroup but not between subgroups. This information is important for diagnosing infection with MCFVs and in the development of vaccines against MCF. 相似文献
6.
Some aspects of uterine and placental growth have been examine during pregnancy in the ewe. Changes in vitro rates of protein synthesis, RNA: DNA and protein: DNA ratios and the tissue concentration of DNA in intercaruncular endometrium and caruncles (cotyledons between days 0 (oestrus) and 112 of pregnancy were compared with corresponding changes in the concentrations of high-affinity cytosol receptors for oestradiol and progesterone in whole uterus and caruncles/maternal cotyledons. Rapid growth of the intercaruncular endometrium between days 28 and 112 and of the developing cotyledons between days 28 and 84 occur in the presence of tissue levels of both steroid receptors that are extremely low in relation to the corresponding levels seen in the uterus at oestrus. If uterine responses to steroid hormones are regulated by the amounts of specific receptors present in the tissue, the results support the concept that uterine growth after day 28 of pregnancy results primarily from the physical stimulus of the growing concepts rather than from the actions of endogenous steroid sex hormones. 相似文献
7.
The morphology and behavior of female rodents is partially masculinized as a result of residence near males in the same uterine horn (Clemens effect). Two hypothetical mechanisms have been proposed to account for this effect. In the first hypothesis (“contiguity”) androgens secreted by males in utero are proposed to diffuse across the amniotic membrane, reaching adjacent fetuses. In the second hypothesis (“caudal male”) androgens are transported via the cervical-to-ovarian blood flow and may diffuse directly between closely apposed uterine veins and arteries. This study was designed to test directly which of these mechanisms appears more influential in masculinizing the morphology of female rats. Pregnant Sprague-Dawley rats were decapitated early on Day 22 of gestation and pups were Caesarean delivered. Their anogenital distance and body weight were recorded, location in utero coded by means of footpad tatooing, and each litter fostered to a maternal female. Measurements were taken again when the animals were weaned. Statistical analysis revealed that the presence of one or more males caudal to a female in the uterine horn has a more critical influence on that female's morphology than contiguity per se. Such a mechanism may result in partial masculinization of dimorphic behaviors later in life. 相似文献
8.
Geraint Florida-james Akthar Wallymahmed Thomas Reilly 《Chronobiology international》1996,13(1):59-69
Daily mood changes were monitored over successive 24-h periods using the Profile of Mood States (POMS) (3) to assess the effect of nocturnal shiftwork on mood. Twenty-three student nurses, age range 19-24 years, were studied throughout their first experience of nocturnal shiftwork. The POMS was administered over four complete solar days during a 12-week period that included an 8-week block of night work. Five POMS dimensions displayed circadian rhythmicity. vigor-activity; fatigue-inertia; confusion-bewilderment; friendliness; and total-mood-disturbance. These five dimensions were sensitive to changes in living patterns, showing phase shifts in their circadian rhythms when subjects alternated between diurnal and nocturnal living patterns. The dimensions were also observed to be sensitive to adjustment to two different nocturnal shiftwork schedules. The subjects who worked “four on, three off showed similar phase shifts to the subjects who worked “eight on, seven off,” suggesting that mood adjustment takes place by the fourth night of a rotation of nights. The “commitment” of the students to the nocturnal living pattern was thought to have a bearing on the adaptation of the students to the nocturnal shifts, as regards mood. 相似文献
9.
P. Schulz S. Lustenberger R. Degli Agosti R. W. Rivest 《Chronobiology international》1994,11(6):367-380
Thyroid-stimulating hormone (TSH), Cortisol, melatonin, prolactin, luteinizing hormone (LH), delta-sleep-inducing peptide (DSIP), its phosphorylated form (P-DSIP), heart rate, and body temperature were measured every half hour during two 24-h periods in five normal men. τ-Amino-butyric acid (GABA) and 3-methoxy-4-hydroxyphenylglycol (MHPG) were measured less frequently. The first period, the “activity” condition, included usual daily activities. The second period, or “rest” condition, consisted of fasting, constant bed rest during 34 h, and partial light deprivation. Compared with the “rest” condition, the “activity” condition increased heart rate, temperature, LH, and TSH in most subjects, and Cortisol in two of five subjects. It retarded the onset of nocturnal Cortisol and melatonin secretion. The temporal pattern and the absolute values of the concentrations of DSIP, P-DSIP, MHPG, GABA, and prolactin showed no or minimal changes during the two conditions. In spite of the influence of the “activity” versus “rest” condition on several hormones, the mean concentrations as well as the temporal organization of their secretion into plasma were quite stable within each subject, whereas they varied much more between individuals. TSH, Cortisol, and melatonin values were also stable within an 8-month period in one subject who was studied on four occasions. The results illustrate that the patterns of hormones rhythms and their reactivity to changes in the environment are, to a large extent, specific to each subject. 相似文献
10.
To determine whether the large morphological differences that occur between populations of Potamogeton pectinatus L. have a genetic basis, the chromosome numbers of several populations were counted. Although several numbers were determined, no correlation between different numbers and populations could be established. The number was always close to 2n = 78, which is that most recorded for P. pectinatus in the literature. However, although some aberrant counts can probably be ascribed to incorrect interpretations of the preparations, some cells undoubtedly contain more than 78 chromosomes. Since the chromosomes of P. pectinatus are very small it is difficult to distinguish between “normal” and “B-chromosomes”, which may be the cause of the higher numbers. 相似文献
11.
The Fisher “Permount” naphthalene polymer, the Hartman Leddon “H.S.R.” terpene polymer resin, a Monsanto polystyrene P-1, the Will Corporation “Diaphane” and “Green Diaphane”, and the du Pont “Lucite” methyl methacrylate polymer were examined, and the possibility of use of some other plastics was also explored. The first 5 mentioned were tested for color preservation of a variety of stains in comparison with Canada balsam and Clarite X. From this point of view polystyrene, the Hartman Leddon “H.S.R.” and the Fisher “Permount” resins were the most satisfactory, then the “Diaphanes”. Both “Permount” and “H.S.R.” show some yellowing. The H.S.R. with a melting point of 115°C, the Permount with 150°C. melting point, and the Polystyrene with a thermal denaturation point above 220°C. all excell Canada balsam in heat resistance. Trimethylbenzene, cymene and monoamylbenzene appear to be the best solvents for polystyrene. Mounts made in a solution of 20 g. polystyrene in 100 ml. trimethylbenzene can be packed flat slide to slide in 24 hours after mounting without sticking together.
This report is not intended to deprecate the use of other resinous mounting media which have not as yet been tested or compared with those mentioned herein. 相似文献
This report is not intended to deprecate the use of other resinous mounting media which have not as yet been tested or compared with those mentioned herein. 相似文献
12.
Activities of glucose-6-phosphate dehydrogenase (E.C. 1.1.1.49; G6PDH) and malate dehydrogenase (E.C. 1.1.1.37; MDH) were determined fluorometrically in freeze-dried sections of the sheep uterus during the estrous cycle and pregnancy. Samples (0.2–0.3 μg) from the luminal epithelium, uterine glands, maternal caruncles, fetal cotyledons and intercotyledonary trophoblast were assayed in a small aliquot (5 μl) of the reaction medium under oil.Activity of G6PDH in the luminal epithelium, uterine glands and maternal caruncles did not change during the estrous cycle. Activity of MDH in the uterine glands did not change during the cycle, but in the luminal epithelium and maternal caruncles highest activities were found on day 9 and day 2 post-estrus, respectively.The enzyme activities in the fetal tissues were lower than in the maternal tissues. In all maternal tissues, MDH and G6PDH activities decreased during early pregnancy, but after implantation, the activities increased significantly. In fetal tissues G6PDH activity increased, whereas MDH activity decreased during the second half of gestation. These results suggest an increased rate of pentose shunt activity in both maternal and fetal tissues, and an increased rate of Krebs' cycle activity in the maternal but not in the fetal tissues. 相似文献
13.
Wearden JH 《Behavioural processes》2008,78(3):374-379
Computer simulation of performance on “normal” and “episodic” temporal generalization tasks was used to examine the relations between the theoretical parameters of models which fit temporal generalization data (“timing sensitivity” and “threshold”), and the d′ (detectability) and beta (decision criterion) measures of signal-detection theory. In general, changes in timing sensitivity altered d′, whereas threshold changes affected beta, supporting the assertion that the two sorts of variables (“sensitivity/detectability” and “threshold/criterion”) were psychologically equivalent. Cases where temporal generalization gradients were apparently contaminated by “random responding” could be treated by changes in beta, but cases in which temporal generalization gradients were not peaked at the standard posed severe problems for a simple signal-detection account, although existing models of temporal generalization performance could deal with them. 相似文献
14.
Viktor Reinhardt Annie Reinhardt 《Journal of applied animal welfare science : JAAWS》2000,3(2):141-149
A survey of 96 primatological articles revealed that cage location of research monkeys is rarely mentioned, although the environment of upper and lower row-housed animals markedly differs in terms of light quality, light intensity, and living dimension. Not accounting for these uncontrolled variables may increase variability of data and, consequently, the number of experimental animals needed to obtain statistically acceptable results. This study concluded that single-tier housing would be an important refinement of research methodology. Such housing would (a) enable all animals of a room to use the “arboreal ”dimension of their enclosure and retreat to “safe ”vantage points above the human “predator, ”(b) offer all animals access to uniform light, and (c) provide more favorable conditions for professional animal care. 相似文献
15.
Yue Zhou Lynn P. Chorich Virendra B. Mahesh Thomas F. Ogle 《The Journal of steroid biochemistry and molecular biology》1993,46(6):687-698
The objective of this study was to examine the mechanisms of estrogen receptor (ER) processing and replenishment in the uterus of ovariectomized rats after estradiol and progesterone treatment. Uterine ER binding activity, ER protein and ER mRNA were measured by receptor binding exchange assay, Western blot and slot blot, respectively. The regulation of ER levels in rat uterus by estradiol and progesterone was very dramatic. Changes in ER protein were faithfully reflected by changes in binding activity. Estradiol caused receptor “processing” within 4 h of administration followed by recovery or “replenishment” of ER levels to the initial level by 20 h. The term “processing” has previously been used to describe the loss of ER binding activity in the early phase of estradiol-action, but it was never clear whether the ligand binding site was inactivated by processing or if the receptor molecule actually disappeared. This study shows that receptor “processing” constitutes disappearance of receptor protein and the later “replenishment” phase represents new ER protein rather than recycling of “processed” receptor. Progesterone-action, on the other hand, influenced only the “replenishment” phase by blocking recovery of ER protein. ER mRNA was suppressed by estradiol at 8 h, after the receptor was “processed” and “replenishment” already initiated. Progesterone, on the other hand, did not alter the steady state level of the message. Other mechanisms, such as regulation of translation rate of existing mRNA and changes in the rate of degradation of ER proteins are more likely involved in acute regulation of ER by these ovarian steroid hormones. 相似文献
16.
Ei-Ichiro Ochiai 《Bio Systems》1978,10(4):329-337
Some basic principles were delineated with regard to the selection of inorganic elements by organisms; they are “basic fitness rule”, “abundance rule”, “efficiency rule” and “evolutionary pressure”. The basic fitness rule was then applied to the case of molybdenum, to show how inherently fit molybdenum is to the biological functions carried out by those enzymes dependent on it, including xanthine oxidase, sulfite oxidase, nitrate reductase and nitrogenase. 相似文献
17.
S. Ferreira-Dias A. C. Correia F. O. Baptista M. M. R. da Fonseca 《Journal of Molecular Catalysis .B, Enzymatic》2001,11(4-6):699-711
Two commercial immobilized lipases (“Lipozyme® IM” and “Novozym® 435”) were tested as biocatalysts for the glycerolysis of olive residue oil in n-hexane aimed at the production of monoglycerides (MG) and diglycerides (DG). A central composite rotatable design (CCRD) was followed to model and optimize glycerolysis as a function of both the amount of biocatalyst (L) and of the molar ratio glycerol/triglycerides (Gly/TG). For both biocatalysts, the production of free fatty acids (FFA) was described by second order models. In terms of MG and DG production, as well as of TG conversion, the best fits were obtained with first-order models. The highest MG productions were in the range 43–45% (w/w, on the basis of total fat) for both biocatalysts tested at a (Gly/TG) ratio of one. In the case of “Novozym 435”, the lowest load used (12%, w/w) gave the best results, in contrast with “Lipozyme IM” with which a concentration of about 26% (w/w) was necessary to obtain the highest production. Under these conditions, the amount of FFA produced was about 2% and 10% (w/w), respectively, for “Novozym 435” and “Lipozyme IM” catalyzed systems. Considering both FFA production and lipase loading, “Novozym 435” was shown to be a better biocatalyst for the glycerolysis of olive residue oil in n-hexane, aimed at the production of MG, than “Lipozyme IM”. 相似文献
18.
Arthur La Velle 《Biotechnic & histochemistry》1985,60(5):271-273
Silver staining has become a versatile method for the visualization of specific cell structures and products. The similarity of the impregnation “nuclei” of reduced silver staining to the silver “specks” or “nuclei” of the latent image in photography is noted. “Physical” development (reduction of ionic silver in solution) in silver staining as compared to “chemical” development (reduction of ionic silver remaining in a silver halide crystal) in photographic procedures is briefly discussed. 相似文献
19.
Richard H.M. Eertman Arco J. Wagenvoort Herman Hummel Aad C. Smaal 《Journal of experimental marine biology and ecology》1993,170(2):179-195
Mussels, Mytilus edulis, were exposed for periods of 6 weeks at various locations in Dutch coastal waters during 1989 and 1990. “Survival in air” showed to be a sensitive response parameter for indicating pollution induced environmental stress in transplanted mussels sampled from eight field sites. Increased tissue contaminant levels, especially PCBs and PAHs, correlated with a reduced survival time during aerial exposure. Three weeks exposure of mussels in the laboratory to 1 μg · 1−1 PCBs affected the aerial survival time negatively. Laboratory experiments did not indicate that lowered salinity influences the “Survival in air” response after sufficient acclimation (15 days), facilitating the use of this response parameter in both marine and estuarine waters. 相似文献
20.
Cytochalasin B (CB) was used to enucleate cells (cytoplasts) and to obtain karyoplasts (nuclei) from the human diploid fetal lung fibroblast strain WI-38. Fusion of cytoplasts and nuclei from young and old cells was accomplished with the aid of inactivated Sendai virus. Viable nuclei may be obtained from the karyoplast pellet after passage through a layer of bovine albumin which retains any contamination cytoplasts. The majority of successful fusions forming “whole cells” occurred when cytoplast from “old” cultures (PDL 40–51) and karyoplasts from “young” cultures were used (PDL 12–22), but almost always resulted in limited division of the viable reconstructed cells. When successful fusion occurred between “young” cytoplasts and “young” karyoplasts the number of cell divisions obtained was comparable to control cells kept under similar conditions. 相似文献