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21.
The distribution of oviductal lymphatic vessels in the bovine mesosalpinx and bursa ovarica, and their communications with other lymphatics in the uterine broad ligament were examined after exposition of all lymphatic pathways with varicoloured microfil and/or ink-gelatin mixture. However, filling of the lumen of the oviductal infundibulum lymphatics was difficult or impossible because of its slender walls. Lymphatics of the isthmus and ampulla with short precollectors formed branches 1.5-2.0 cm long on both sides: dorsal and ventral of the uterine broad ligament. Collectors with slender and long lymphangions, visible after filling their lumen, encircled the alymphatic area in the parainfundibullar mesosalpinx. The greatest number of lymphatic branches, which originated from the paraisthmal part of the oviductal ampulla were observed in the subovarian area. The characteristic feature was their immediate proximity with uterine and oviductal arterial vessels. Subsequent studies have provided convincing evidence that there are direct connections of lymphatics leaving the oviduct and ovarian sac with lymphatics emerging from the uterus and ovary (after bilateral filling of lymphatics pathways in the whole broad liagment of the uterus). The performed investigations showed particularly characteristic feature in the cow--mixing lymph leaving various reproductive organs in the area of the right and left ligament--before two long collector branches reach the nearest lymphatic node/-s.  相似文献   
22.
The thalamic nuclei with their defined set of input-output connections are the primary channel for information flow to the cerebral cortex. Several data suggest that neurons of that area are involved in the response to various aversive stimulations. However the pattern of activation seems to depend on the stress model as well as the stage of maturation. In the present study we would like to check which nuclei of the thalamus show expression of c-fos in the response to the "open field test", and how this response pattern changes during the maturation process. 30 rats of age ranged from P0 to P120 (P-postnatal day) were studied. The experimental group was exposed to the "open field test" for 10 minutes. After perfusion and fixation, brains were cut and stained for c-fos with immunohistochemical method. Our results showed that during development the pattern of c-fos activity in the thalamic nuclei after stress stimulation undergoes significant changes. Distinct c-fos expression was observed in the paraventricular nucleus, intergeniculate leaflet and ventral lateral geniculate nucleus. These findings suggest that these nuclei may play a direct role in the stress reaction involved in the response to the "open field test".  相似文献   
23.
24.
The direct effects of alpha- and beta-adrenergic agents on PRL and beta-endorphin (beta-END) secretion in vitro by porcine pituitary cells have been investigated. Pituitary glands were obtained from mature gilts, which were ovariectomised (OVX) one month before slaughter. Ovariectomised gilts, assigned to four groups, were primed with: (1) vehicle (OVX); (2) and (3) oestradiol benzoate (EB; 2.5 mg/100 kg b.w.) at 30-36 h (OVX+EB I) and 60-66 h (OVX+EB II) before slaughter, respectively; and (4) progesterone (P4; 120 mg/100 kg b.w.) for 5 consecutive days before slaughter (OVX+P4). Isolated anterior pituitary cells were submitted to 3.5 h incubation in the presence of GnRH, alpha- and beta-adrenergic agonists [phenylephrine (PHEN) and isoproterenol (ISOP), respectively], or alpha- and beta-adrenergic blockers [phentolamine (PHENT) and propranolol (PROP), respectively]. The culture media were assayed for PRL (exp. I) and beta-endorphin-like immunoreactivity (beta-END-LI) (experiment II). In experiment I, GnRH did not influence PRL release by pituitary cells in all experimental groups. Some of tested doses of adrenergic agonists, PHEN and ISOP, increased PRL release from pituitary cells of OVX gilts, but not from those of OVX+EB I animals. In the OVX+EB II group, PHEN alone, but ISOP with PROP, potentiated PRL secretion by the cells. In OVX+P4 animals, PHEN alone or in combination with PHENT and also ISOP alone or with PROP enhanced PRL output from the cells. In experiment II, addition of GnRH increased beta-END-LI release from pituitary cells only in the OVX+EB II group. PHEN and PHENT potentiated beta-END-LI secretion by pituitary cells in OVX+EB II and OVX+P4 groups, while ISOP and PROP increased beta-END-LI secretion by the cells of OVX and OVX+EB II animals. In turn, in the OVX+EB I group, effect of PHENT and PROP on PRL secretion by pituitary cells was inhibitory. In conclusion, our results suggest that adrenergic agents can modulate PRL and beta-END secretion by porcine pituitary cells in a manner dependent on the hormonal status of gilts.  相似文献   
25.
The hypothesis that epinephrine (noradrenaline, NA) enhances utilisation of high-density lipoproteins (HDL) by bovine luteal cells and that this process involves phospholipase (PL) C and protein kinase (PK) C intracellular pathway was tested. Luteal cells from days 2-4, 5-10 or 11-17 of the oestrous cycle were preincubated for 20 h. Subsequently DMEM/Ham's F-12 medium was replaced by fresh medium and the cells were treated for 6 h as follows: In Experiment I with HDL (5-75 micrograms cholesterol per ml), NA, isoprenaline (ISO) or luteinising hormone (LH). In Experiment II cells were incubated for further 24 h in deficient medium (without FCS) and next treated as in Experiment I. In Experiment III cells were stimulated with NA, ISO or LH alone and together with HDL. In Experiment IV cells were treated with PLC inhibitor (U-73122) or with PKC inhibitor (staurosporine) or stimulator (phorbol 12-myristrate 13-acetate) and with either NA, insulin or LH. Only luteal cells from days 5-10 of the cycle responded on HDL and beta-mimetics (P < 0.05). LH stimulated progesterone secretion from the luteal cells during all stages of the cycle (P < 0.001). Cells incubated in deficient medium and supplemented with HDL secreted as much progesterone as those stimulated by LH in all stages of the cycle. Beta-mimetics were unable to enhance the stimulatory effect of HDL. Blockade of PLC had no influence on progesterone secretion from cells treated with either NA or LH, but this did impair the stimulatory effect of insulin (P < 0.05). Similarly, blockade of PKC by staurosporine impaired (P < 0.05) the effect of insulin only but not that observed after LH or NA treatment. We suggest that: (a) noradrenergic stimulation does not enhance utilisation of cholesterol from HDL for progesterone secretion; (b) the fasting of luteal cells seems to activate enzymes responsible for the progesterone synthesis; (c) effect of NA on progesterone secretion from luteal cells does not involve the PLC-PKC pathway.  相似文献   
26.
In this study, results of histopathological investigations of meat samples collected from turkeys with macroscopically recognized green muscle disease were compared with those obtained from turkeys without macroscopic signs of this syndrome. The histopathological lesions were assessed based upon the self-designed 7-grade scale of the intensity of changes. The greatest intensity of the histopathological alterations were found in the smaller pectoral muscle collected from turkeys in which macroscopical signs of the green muscle disease were observed. Similar changes were also found in the greater pectoral muscle, however, they were less intense than those determined in the smaller pectoral muscle.  相似文献   
27.
Two field experiments (Experiment I in 2003–2005 and Experiment II in 2004–2005) with carrot c.v. ‘Kazan F1’ were conducted at Trzciana village (50°06′N, 21°85′E). The experiments were arranged in a split-plot design with four replications. Two sub-blocks were identified in both experiments: I, without foliar nutrition; II, receiving plant foliar nutrition. The plants were sprayed three times alternately with: 2% urea solution, 1% solution of multi-component ‘Supervit R’ fertilizer (produced by Intermag, Poland) and again with 2% urea solution. Combinations with diversified nitrogen fertilization were distinguished within both sub-blocks. Experiment I comprised of: (1) Control, (2) Ca(NO3)2 70, (3) Ca(NO3)2 70 + 70, (4) (NH4)2SO4 70 and (5) (NH4)2SO4 70 + 70. Experiment II included: (1) Control, (2) ENTEC-26 35 + 35, (3) ENTEC-26 70 + 70, (4) ENTEC 26 105 + 105, (5) NH4NO3 35 + 35, (6) NH4NO3 70 + 70, (7) NH4NO3 105 + 105. Where 70 kg N ha−1 was used before sowing, whereas 35 + 35, 70 + 70 and 105 + 105 kg N ha−1 were applied before sowing and as top dressing. Solid nitrogen fertilizer was added to the soil (produced by): Ca(NO3)2, Yara International ASA (Hydro); (NH4)2SO4, Zak?ady Azotowe in Tarnów, Poland; NH4NO3, Zak?ady Azotowe in Pu?awy, Poland; and ENTEC-26, COMPO GmbH & Co. KG, Germany. The research aimed at determining the effect of diversified nitrogen fertilization and foliar nutrition on NO3, NH4+, N-total and dry matter (d.m.) concentrations in carrot, and N uptake by storage roots. In Experiment I, nitrogen fertilization did not affect NO3 concentration, whereas in Experiment II, the applied N treatment increased NO3 concentration in carrot in relation to the control, except for the storage roots of plants fertilized with ENTEC-26 35 + 35. Nitrogen fertilization applied in both experiments caused a significant increase in N-total concentration in carrot and N uptake by storage roots in comparison with the control plants. In both experiments, nitrogen fertilization had a different effect on the concentrations of NH4+ and d.m. in carrot. What is more, foliar nutrition treatments in both experiments had a different effect on the concentrations on NO3, N-total, d.m. in carrot and N uptake by carrot storage roots.  相似文献   
28.
Seasonal variations in beta carotene intake and low levels of beta carotene and vitamin A in blood plasma were found in cows fed ration based mainly on maize silage. The supplementation of daily winter rations with 300 mg Rovimix-beta carotene per cow, beginning 14 days before parturition and 60 days after calving increased slighty the beta carotene and vitamin A concentrations of blood plasma and improved some fertility indices: the number of inseminations per cow was reduced and the percentage of conception rate was significantly higher. It may be assumed that beta carotene content in feeds and it's utilization rate generally reflected in beta carotene blood plasma level and in the improvement of fertility.  相似文献   
29.
Six pigs of initial weight 40 +/- 1.7 kg with a T-piece cannula fitted at the terminal ileum were given diets composed of 96.3% of rye, barley or triticum grains ground to pass the 2.6 mm mesh, 3.3% mineral and vitamin mixture and 0.4% Cr2O3. Each diet was given to all pigs in a Latin square design, and faeces and ileal digesta were collected on 7, 8, 9 and 10, 11 and 12 day of feeding each diet, respectively. The grains varied widely in the content of pentosans, polyuroids, beta-glucan and monosaccharides. The antitrypsin activities were 0.84, 2.73 and 1.62 TUI/g in barley, rye and triticum, respectively. Ileal and faecal apparent digestibilities of nitrogen and amino acids were higher (P less than or equal to 0.01) in Triticum than in barley and rye. The digestibility of carbohydrates (pentosans, beta-glucan, polyuroids and non-structural carbohydrates) were lower in pigs fed a rye diet than of those fed a Triticum diet. The results are discussed with respect of the role to non starch polysaccharides, especially pentosans in digestibility of nitrogen and energy in animals receiving a rye diet.  相似文献   
30.
Analytical studies were conducted on the species composition of galls occurring on the leaves of Salix purpurea L. in the Ojców National Park in 1999?–?2000. The species composition of galls was identical in two consecutive years. Galls were caused by 5?species (a total of 480?galls). The most numerous species in both years was Pontania viminalis (L.). Index of occurrence frequency and Agrell's index of species co-existence have been calculated. This index reached the highest values in case of Pontania dolichura (Thoms.) and P. viminalis (L.) in 1999 as well as Phyllocolpa leucaspis (Tischb.) and P. viminalis (L.) in 2000.  相似文献   
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