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1.
Antibodies to Neospora caninum and Toxoplasma gondii were assayed in sera of 396 opossums (Didelphis marsupialis) from the city of S?o Paulo, Brazil. Antibodies to N. caninum were assayed using the indirect immunofluorescent antibody test (IFAT). Antibodies (IFAT, approximately 1:25) to N. caninum were found in 84 opossums (D. marsupialis) in titers of 1:25 in 46, 1:50 in 20, 1:100 in 17, and 1:400 in 1. Antibodies to T. gondii were assayed with the modified agglutination test (MAT) and the IFAT. Antibodies to T. gondii (MAT, approximately 1:25) were found in 82 (20.4%) of the 396 opossums, in titers of 1:25 in 24, 1:50 in 26, 1:100 in 18, 1:200 in 13, and 1:800 in 1. The IFAT antibodies to T. gondii were found in 148 of 396 opossums, in titers of 1:16 in 41, 1:32 in 23, 1:64 in 13, 1:128 in 6, 1:256 in 20, 1:512 in 17, 1:1,024 in 10, 1:2,048 in 10, 1:4,096 in 7, and 1:8,192 in 1. This is the first report of N. caninum and T. gondii infections in D. marsupialis.  相似文献   

2.
Lipid content in mammalian oocytes or embryos differs among species, with bovine and porcine oocytes and embryos showing large cytoplasmic droplets. These droplets are considered to play important roles in energy metabolism during oocyte maturation, fertilisation and early embryonic development, and also in the freezing ability of oocytes or embryos; however, their detailed distribution or function is not well understood. In the present study, changes in the distribution and morphology of porcine lipid droplets during in vivo and in vitro fertilisation, in contrast to parthenogenetic oocyte activation, as well as during their development to blastocyst stage, were evaluated by transmission electron microscopy (TEM). The analysis of semi-thin and ultra-thin sections by TEM showed conspicuous, large, electron-dense lipid droplets, sometimes associated with mitochondrial aggregates in the oocytes, irrespective of whether the oocytes had been matured in vivo or in vitro. Immediately after sperm penetration, the electron density of the lipid droplets was lost in both the in vivo and in vitro oocytes, the reduction being most evident in the oocytes developed in vitro. Density was restored in the pronculear oocytes, fully in the in vivo specimens but only partially in the in vitro ones. The number and size of the droplets seemed, however, to have decreased. At 2- to 4-cell and blastocyst stages, the features of the lipid droplets were almost the same as those of pronuclear oocytes, showing a homogeneous or saturated density in the in vivo embryos but a marbled or partially saturated appearance in the in vitro embryos. In vitro matured oocytes undergoing parthenogenesis had lipid droplets that resembled those of fertilised oocytes until the pronuclear stage. Overall, results indicate variations in both the morphology and amount of cytoplasmic lipid droplets during porcine oocyte maturation, fertilisation and early embryo development as well as differences between in vivo and in vitro development, suggesting both different energy status during preimplantation development in pigs and substantial differences between in vitro and in vivo development.  相似文献   

3.
Regional isolation perfusion with an alkylating agent was carried out in a small community hospital, using readily available equipment, ten times in nine cases of advanced malignant disease. Visible regression of tumor, either grossly or histologically, occurred in seven patients and decided subjective improvement occurred in five patients.The long range effect of the procedure could not be determined in the present series, not enough time having elapsed.Side effects included jaundice in four patients, massive necrosis of the tumor in one patient, nausea and vomiting in three patients, postoperative edema in five patients, wound infection in two patients, Horner''s syndrome in one patient, temporary alopecia in three patients, and depression of hemoglobin level in seven patients, of the leukocyte count in four patients and of the platelet count in four patients.A feature of the procedure used in the present series was a system of monitoring the escape of alkylating agent into the systemic circulation.  相似文献   

4.
广东大中型水库底泥重金属含量特征及潜在生态风险评价   总被引:18,自引:1,他引:17  
广东省45宗大中型水库底泥重金属含量分析评价结果表明:除Cr外,广东省大中型水库底泥中Cu、Zn、Pb和Cd含量均高于广东省土壤重金属含量背景值.广东省四大地理区域中,粤北地区大中型水库底泥Cu、Zn、Pb和Cd平均含量均为最高,分别为89.71、321.21、154.95mg/kg和1.46mg/kg;其次是粤东和粤中地区;粤西大中型水库底泥Cu、Zn、Pb和Cd平均含量均为最低,但Cr平均含量居四大区域之首,为130.81mg/kg.粤东和粤北大中型水库底泥重金属富集系数以Cd最高;粤中和粤西大中型水库底泥重金属富集系数则以Cu最大.总体而言,粤北大中型水库底泥重金属具有很强的潜在生态风险,粤东和粤中大中型水库底泥重金属潜在生态风险程度为中等;粤西大中型水库底泥重金属属于轻微生态风险程度.结果说明,广东省大部分地区大中型水库底泥的重金属潜在生态风险主要是由于底泥中Cd的潜在生态风险系数过高所造成.人为生产活动,特别是矿产开采造成的污染是广东省大中型水库底泥重金属潜在生态风险等级提高的主要原因.  相似文献   

5.
The interaction is reported of selected chemical elements (cadmium, calcium, copper, iron, magnesium, manganese, strontium, and zinc) in cultured sea water, with soft tissues, prismatic calcite of the right valve, and foliated calcite of right and left valves of genetically similar American oysters, Crassostrea virginica (Gmelin) grown in a natural habitat and in two environmentally controlled experimental systems (flow-through and recycle). The addition of trace elements as algal nutrients in ambient sea water was reflected in higher concentrations of trace metals in shells and soft tissues of oysters grown in experimental systems. Calcium was relatively uniformly distributed in major regions of valves from the three habitats, even though its concentration fluctuated widely in sea water in experimental systems. Magnesium and strontium were most concentrated in valves of oysters grown in the recycle system (magnesium in the prismatic layer of the shell and strontium in the foliated calcite). Iron was uniformly distributed. Cadmium, copper, manganese, and zinc were most concentrated in the prismatic calcite of valves from the flow-through system. In soft tissues, calcium was more concentrated in oysters from experimental systems than in those from the natural habitat. Manganese was about equally distributed in soft tissues from the three habitats, whereas copper and iron were more concentrated in soft tissues in experimental systems than in the natural habitat, and were many times more concentrated in soft tissues than in valves from all three habitats. As concentrations of magnesium, strontium, mangenese, zinc, and cadmium increased in valves in experimental systems, pigmentation of valves decreased. The study confirmed the capacity of oysters to concentrate several elements in their valves as concentration of these elements increased in ambient sea water and disclosed the heterogeneous distribution of these elements in major regions of the valves.  相似文献   

6.
啮齿动物作用下退耕地山杏种子扩散与贮藏的季节变化   总被引:2,自引:0,他引:2  
啮齿动物对植物种子的取食和扩散影响种子的时空分布,继而影响种子的萌发和幼苗建成,因而在森林更新中起着重要作用.在国有济源市愚公林场,选择退耕地生境,于春季、夏季、秋季分别释放人工标记的山杏种子,观察啮齿动物扩散与埋藏山杏种子的季节性差异.结果表明:1)退耕地中的啮齿动物主要包括大林姬鼠、社鼠、黑线姬鼠;2)山杏种子扩散速率在春季显著慢于夏季,夏季显著慢于秋季;3)种子搬运量受季节和种子状态交互作用影响,春季显著少于夏季,夏季显著少于秋季;4)不同季节种子平均搬运距离不同,秋季不同状态种子的搬运距离均大于春季和夏季;5)啮齿动物对山杏种子的贮藏点大小多为1粒种子,少量为2、3粒种子,且贮藏点大小与季节间存在显著的交互作用,春季单粒种子的贮藏点数量显著少于夏季和秋季,而夏季与秋季的贮藏点则倾向于多粒种子;6)在夏季和秋季各有5枚(共释放1800枚)被啮齿动物分散贮藏的山杏种子建成幼苗.  相似文献   

7.
Intracellular pH was determined (DMO method) in European hamsters, in the spontaneously-occurring respiratory acidosis of hibernation, in hypercapnia due to breathing 12% CO2 in air in euthermy in spring, and in euthermicnormocapnic controls. From euthermy to hibernation, the temperature coefficient of pH was lowest in blood plasma and brain, intermediate in striated muscles (thigh muscles and diaphragm), and highest in heart and liver (Fig. 1). Correspondingly, the estimated dissociation ratio of the protein imidazole buffer groups, alpha Im, decreased markedly in plasma and brain, denoting an acid titration, but varied little in liver and heart. Striated muscles were intermediate (Fig. 2). Like in other mammals, intracellular responses to short-term euthermic respiratory acidosis were characterized by a partial metabolic compensation in the brain and a small metabolic acidification in striated muscles. In hibernation, a powerful metabolic compensation took place in liver and heart, nearly restoring alpha Im, but none occurred in brain (Figs. 3 to 5). The existence of an intracellular acidosis in brain and striated muscles during hibernation is in keeping with an inhibitory role of acidosis, whereas the homeostasis of intracellular alpha Im in liver and heart would subserve the eurythermal functioning of metabolic regulations in these organs, like in most organs of ectotherms.  相似文献   

8.
A galanin (GAL)-like peptidergic system was investigated in the brain of Anguilla anguilla subjected to hyperosmolar and hypoosmolar conditions, by using antisera raised against porcine 1-29 GAL. A group of immunoreactive perikaria was identified in the periventricular hypothalamus, in the ventral thalamus, in the pretectal areas and in the optic tectum. Immunoreactive perikaria were present in the nucleus lateralis of the torus semicircularis in seawater (SW) adapted eels, and were absent in the freshwater (FW) adapted eels. Galaninergic fibres were observed in many areas of the brain. The immunoreactive perikaria and fibres, when localised in the same areas, were more strongly labelled and numerous in the SW adapted eels in comparison to the FW adapted animals. GAL-specific binding sites, investigated by autoradiography using iodinated porcine GAL, occurred in several regions of the brain, in particular in the dorsal telencephalon, in the dorsal thalamus and in the torus semicircularis, where a high density of binding sites was observed in the SW adapted eels. Conversely, a higher density of binding sites was observed in the caudal substantia reticularis and in the corpus cerebelli in the FW adapted eels. We conclude that different distributions and intensity in immunoreactive elements occur in response to the two environmental conditions.  相似文献   

9.
植物叶片的非结构性碳水化合物(NSC)不仅可以反应植物的碳供应状况,也能反应植物对外界环境的适应策略。利用传统的蒽酮比色法测定了东北3个典型森林生态系统(呼中、凉水和长白山)242种常见植物叶片的非结构碳水化合物,探讨了温带主要森林植物叶片NSC沿纬度梯度的变化趋势及其在物种-生活型-群落间的分布规律。实验结果表明:3个典型森林生态系统植物叶片可溶性糖、淀粉和NSC含量均呈偏正态分布,多数物种的含量偏中低水平;242种植物叶片可溶性糖、淀粉和NSC的平均含量分别为63.31、65.66和128.96 mg/g。在所调查的森林生态系统中,叶片可溶性糖、淀粉和NSC含量在不同生活型中表现各异。此外,乔木植物叶片的可溶性糖、淀粉和NSC含量从北到南呈递增趋势,呼中最低,凉水次之,长白山最高。乔木淀粉含量均表现为落叶树种大于常绿树种,可溶性糖和NSC含量变化趋势复杂。研究结果不仅为阐明东北主要森林生态系统植被碳代谢和生长适应对策提供数据基础,而且对理解植物对未来气候变化的响应机理提供数据支撑。  相似文献   

10.
Specific binding sites for cholecystokinin (CCK) and substance P (SP) were detected in the brain of a marine teleost fish, the sea bass, after in vitro incubation of tissue sections with the tritiated peptides and light microscopic autoradiography. Specific binding sites for [3H]-CCK were detected in the dorsal and ventral telencephalon, in the preoptic, tuberal and posterior hypothalamus, in the optic tectum, in the valvulla cerebelli, in the vagal lobe and further in a dorsal location in the medulla oblongata. Areas rich in [3H]-SP binding were located in the ventral telencephalon, in the entire hypothalamic and thalamic region, in the midbrain tegmentum, in the optic tectum, in the valvulla cerebelli and in the medulla oblongata. The distribution of these binding sites seemed to match fairly well with the location of the corresponding immunoreactive elements, although some minor mismatches could be observed. These autoradiographic findings provide the first anatomical evidence for the presence of CCK-like and SP-like binding sites in the brain of a teleost fish.  相似文献   

11.
Abstract— Pentobarbitone sodium anaesthesia was found to produce an increase in protein content in some regions of the rat brain, i.e. posterior cortex, caudate nucleus, and a decrease in protein content in the ventral cortex.
Acetylcholinesterase expressed in terms of wet weight was found to increase in the cerebellum, medulla, and to decrease in the medial cortex, hippocampus, thalamus and caudate nucleus. The changes in activity were not explicable in terms of a direct effect of the anaesthetic on the enzyme. A decrease in protein content of rat brain was observed in the frontal cortex, ventral cortex, hippocampus and caudate nucleus after electrical shocks. Following shock avoidance conditioning procedure (shuttle-box), decreases in protein content were observed in the medial cortex, posterior cortex, cerebellum and ventral cortex; in the thalamus an increase in protein content was observed.
Changes in AChE activity were observed following footshock in the frontal cortex and medulla where there was an increase in activity and in the caudate nucleus, hypothalamus, thalamus, and olfactory tubercle where there was a decrease in activity.
Following shock avoidance conditioning the activity of the AChE increased in posterior cortex, hippocampus, thalamus and hypothalamus and the activity of the enzyme decreased in the ventral cortex.  相似文献   

12.
The small ubiquitin-related modifier-1 (SUMO-1) with broad cellular expression has been implicated in a range of cellular processes, such as cell proliferation, differentiation, and apoptosis. As shown recently, SUMO-1 is expressed and regulated by gonadotropins, in particular an ovulatory hCG stimulus in mouse granulosa cells in vivo. To test the hypothesis that modulation of granulosa cell apoptosis changes SUMO-1 expression during granulosa cell differentiation in the mouse ovary, we demonstrate that progesterone receptor (PR) proteins are absent in pre-ovulatory granulosa cell nuclei, whereas they are expressed in periovulatory granulosa cell nuclei in parallel with decreases in SUMO-1 expression, caspase-3 activation, and DNA fragmentation in vivo. Second, treatment with either PR antagonists or a cell permeable ceramide analog consistently increases SUMO-1 expression in parallel with an increase in apoptosis as well as a decrease in cell proliferation in periovulatory granulosa cells in vitro. However, we do not observe an increase in SUMO-1 expression in pre-ovulatory granulosa cells that have undergone the same treatment. Third, we have also demonstrated, in pre-ovulatory granulosa cells in vitro, neither induction of spontaneous apoptosis nor the protective effect of EGF against spontaneous apoptosis changes SUMO-1 protein expression. Fourth, we show that induction of apoptosis enhances SUMO-1 conjugation in periovulatory granulosa cells in vitro, pointing to the pivotal link between the SUMO-1 conjugation and cell death. Taken together, our observations suggest that SUMO-1 via sumoylation has an important role in the regulation of granulosa cell apoptosis during granulosa cell differentiation in the mouse ovary.  相似文献   

13.
The seroprevalence of Toxoplasma gondii infection in sheep (Ovis aries) in northern Mexico is largely unknown. Antibodies to T. gondii were determined in serum samples from 511 sheep from 8 farms in Durango State, Mexico, using the modified agglutination test (MAT). Sheep were raised in 3 geographical regions, i.e., mountainous (n = 68), semi-desert (n = 132), and valley (n = 311). Overall, T. gondii antibodies were found in 77 (15.1%) of 511 sheep, with MAT titers of 1∶25 in 27, 1∶50 in 10, 1∶100 in 11, 1∶200 in 11, 1∶400 in 8, 1∶800 in 3, 1∶1,600 in 4, and 1∶3,200 in 3. The seroprevalence of T. gondii infection increased significantly with age, indicating post-natal transmission. In contrast, gender, breed, flock size, and geographic region did not significantly influence the seroprevalence. Seropositive sheep were found in 7 of 8 farms sampled. This is the first report of T. gondii infection in sheep in Durango State, Mexico. Results indicate that infected sheep are probably an important source of T. gondii infection for humans in Durango State.  相似文献   

14.
社鼠组织器官同工酶的研究   总被引:5,自引:0,他引:5  
傅必谦  袁虹 《兽类学报》1997,17(2):141-145
用聚丙烯酰胺凝胶等电聚焦电泳方法,分析了社鼠的肝、肾、心肌、骨骼肌、肺、脾和脑等多种组织器官的LDH、ADH、EST、和SOD4种同工酶,对各组织器官的酶带数目和分布,以及酶活性进行了比较研究。结果表明,社鼠的LDH同工酶、ADH同工酶和EST同工酶具有比较明显的组织特异性,而SOD同工酶的组织特异性较低。肺和脾除EST同工酶活性较高外,脑除LDH同工酶活性较高外,其它3种同工酶的活性均较低;而肝和肾中4种同工酶的活性普遍很高。心肌和骨骼肌因氧张力不同而使LDH同工酶酶谱存在明显差异,但其它3种同工酶酶谱却非常相似。同工酶的组织特异性与各组织器官所执行的生理功能是相一致的  相似文献   

15.
The allele and genotype frequencies of the tetranucleotide tandem repeat (TTR) of CFTR intron 6B were analyzed in eight ethnic populations of the Volga-Ural region, including Bashkir, Tatar, Chuvash, Mari, Mordvinian, Udmurt, Komi-Permyak, and Russian. The most common TTR allele 7 varied in frequency from 0.636 in Chuvash to 0.805 in Mordvinians. The frequency of the second common allele 7 ranged from 0.188 in Mordvinians to 0.333 in Chuvash. Allele 8 was found in about 8% of Udmurts and Mari; occurred in a few Bashkirs, Tatars, Mordvinians, and Komi-Permyaks; and was not observed in Russians. The genetic diversity coefficient was minimal in Mordvinians (0.496) and in Tatars (0.505), indicating their low heterogeneity in TTR. The observed heterozygosity was maximal in Udmurts (0.532) and Komi-Permyaks (0.560) and minimal in Mordvinians (0.297). In total, the populations proved to be heterogeneous in TTR allele frequency distribution, the interpopulation difference being significant in most cases.  相似文献   

16.
The distribution of vasotocin and mesotocin in the pituitary and central nervous system in male chickens was determined using radioimmunoassays. Neither peptide was detected in the pineal. Mesotocin, but not vasotocin, was detected in the cerebellum. Both peptides were found in the septal area, archistriatum, paleostriatum, optic lobe, anterior, medial and posterior hypothalamus, midbrain, pons, medulla oblongata, and the anterior and posterior pituitary. Equal amounts of the 2 peptides were present in the septal area, archistriatum and anterior hypothalamus whereas vasotocin was more abundant (2- to 10-fold) in the paleostriatum, optic lobe, midbrain, and pituitary. The amount of mesotocin was about twice that of vasotocin in the medulla oblongata and the medial and posterior hypothalamus. The wide distribution of vasotocin and mesotocin in extrahypothalamic sites in the central nervous system suggests that the peptides may, as in mammals, have a role in a variety of autonomic and endocrine regulatory processes in chickens.  相似文献   

17.
In sea urchin embryos exposed to 14C-proline at 20°C for 3 hr at the gastrula, prism or pluteus stage, 14C-radioactivity was found in hot acid-extractable proteins, in which more than 4% of the radioactivity was detectable in hydroxyproline residues. In these embryos, 14C-radioactivity in collagen-like proteins was found in the archenteron, spicule and embryo-wall cells. The rate of synthesis of collagen-like proteins was highest in the archenteron in the mid-gastrula stage, in the embryo-wall cells in the prism stage and in the spicule in the pluteus stage. The rate of synthesis decreased in the archenteron and increased in embryo-wall cells in the period between the mid- and late-gastrula stages, when the rate of synthesis in the spicule was quite low. Thereafter, the rate decreased slightly in the embryo-wall cells, was maintained in archenteron and increased markedly in the spicule. The rates of synthesis of collagen-like proteins are high in these embryonic organs at stages at which development and growth respectively, occur in embryos. Therefore, synthesis of collagen-like proteins probably supports morphogenesis in these embryonic organs.  相似文献   

18.
The laminar distribution of binding to a number of postsynaptic neurotransmitter receptors was assessed autoradiographically in postmortem samples of area 23a in posterior cingulate cortex from 13 Alzheimer and nine age-matched control cases. Specific binding in all Alzheimer cases was compared to that in control cases, and the following alterations were observed: reduced muscimol binding in most layers; no changes in pirenzepine binding; and elevated cyanopindolol binding in layers Ic, IIIc, and IV. The Alzheimer cases were classified further on the basis of neuronal degeneration: class 1, no neuron loss; class 2, greatest losses in layer II or III; class 3, greatest losses in layer IV; and class 4, greatest losses in layer V or VI. This classification uncovered further alterations in ligand binding patterns. First, muscimol binding was reduced in layers II and III only in class 2 cases and in layers V and VI only in class 4 cases. Second, pirenzepine binding was reduced in layers Ic, IIIa-b, and VI of class 1 cases and layers Va and VI of class 4 cases. In spite of neuron degeneration in classes 2 and 3, there was no change in pirenzepine binding in these classes. Third, elevated cyanopindolol binding occurred in classes 3 and 4, whereas classes 1 and 2 had normal levels of binding. These results suggest that cases of Alzheimer's disease express heterogeneities in neocortical pathology which are reflected in the laminar patterns of binding to postsynaptic receptors. Reductions in muscimol binding to the gamma-aminobutyric acidA receptor had the closest relationship with neuron degeneration, whereas pirenzepine binding appeared to reflect a compensation in muscarinic receptors for changes in neuron densities.  相似文献   

19.
The relationship between branchial carbonic anhydrase (CA) activity, CA gene expression and salinity, and potential mechanisms of regulation, was investigated in the euryhaline green crab, Carcinus maenas, acclimated to 33 ppt and transferred to 10 ppt, and the stenohaline rock crab, Cancer irroratus, acclimated to 32 ppt and transferred to 18 ppt. CA activity in green crabs acclimated to high and low salinity was a function of CA mRNA expression, with low salinity exposure resulting in an increase in both CA expression and activity. Eyestalk ablation (ESA) in green crabs acclimated to high salinity resulted in an increase in CA expression in the posterior, ion-transporting gills, in the absence of the low salinity stimulus. There were no changes in CA activity or expression in the anterior, respiratory gills. ESA also potentiated low salinity-stimulated CA induction, again, only in posterior gills. There were no changes in CA activity in any gills of Cancer irroratus, in response to either ESA or low salinity. These results suggest that CA expression in euryhaline, osmoregulating species, is under inhibitory regulation by a putative repressor found in the eyestalk, and that this mechanism is absent in stenohaline, osmoconforming species. CA expression is maintained at low, baseline levels in crabs acclimated to high salinity by the presence and action of this compound. The effects of the repressor appear to be reduced upon exposure to low salinity, allowing CA induction to occur.  相似文献   

20.
The secretory phospholipase A2 (sPLA2) family in mammals contains more than 10 enzymes. In this study, we examined by immunohistochemistry the localization of six sPLA2s (IIA, IID, IIE, IIF, V and X) in human heart, kidney, liver and stomach. In normal hearts, sPLA2-IIA was detected in coronary vascular smooth muscle cells (VSMC) and sPLA2-V in cardiomyocytes beneath the endocardium. In infarcted hearts, expression of these two enzymes was markedly increased in damaged cardiomyocytes, and expression of sPLA2-IID and-IIE, which was undetectable in normal hearts, was elevated in damaged cardiomyocytes and VSMC, respectively. In infarcted kidneys, sPLA2-IIA and-V were markedly induced in the uriniferous tubular epithelium. In livers affected by viral hepatitis, sPLA2-IIA and-V were expressed in hepatocytes with fatty degeneration. In the gastric glands exhibiting intestinal metaplasia, sPLA2-IIA was localized in the glandular base, sPLA2-IID and-V in the glandular body epithelium, sPLA2-IIE and-IIF in goblet cells in the foveolar epithelium, and sPLA2-X in both glandular body epithelial cells and foveolar epithelial goblet cells. In the gastric submucosal tissues, sPLA2-IIA and-IIE were located in VSMC and sPLA2-V was in the interstitial fibroblasts. In addition, sPLA2-IIA,-IIE,-IIF and-X were highly expressed in gastric signet ring cell carcinoma. Thus, individual sPLA2s exhibit unique cellular localizations in each tissue, suggesting their distinct roles in pathophysiology.  相似文献   

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