共查询到20条相似文献，搜索用时 281 毫秒
1.
Hanen Bouaziz Kamel Jammoussi Fatma Ayedi Najiba Zeghal 《Pesticide biochemistry and physiology》2006,86(3):124-130
In this investigation, we have evaluated the effect of sodium fluoride (NaF) on hepatic function in pregnant and lactating mice and their suckling pups. Experiments were carried out on female Wistar mice given 500 ppm sodium fluoride (226 ppm fluoride ion) in their drinking water from the 15th day of pregnancy until day 14 after delivery. All mice were sacrificed on day 14 after parturition. Our results showed a significant decrease in serum levels of total protein and albumin, a marked hypoglycaemia and a significant decline in serum cholesterol and triglyceride levels in fluoride-treated mice and their pups. Whereas globulin and biluribin levels in serum were not significantly changed by NaF treatment. On the other hand, serum transaminase activities (aspartate transaminase; alanine transaminase), which well known as markers of liver function, were elevated indicating hepatic cells’ damage after treatment with fluoride. Lipid peroxidation increased in NaF-treated mice and pups, as revealed by high liver malondialdehyde levels, while serum total antioxidant status showed a significant decline. These biochemical modifications in NaF-treated mice also correspond histologically with extensive ballooning, hepatocellular necrosis and infiltration of mononuclear cells. These effects were not observed in controls. 相似文献
2.
《Pesticide biochemistry and physiology》2007,87(3):124-130
In this investigation, we have evaluated the effect of sodium fluoride (NaF) on hepatic function in pregnant and lactating mice and their suckling pups. Experiments were carried out on female Wistar mice given 500 ppm sodium fluoride (226 ppm fluoride ion) in their drinking water from the 15th day of pregnancy until day 14 after delivery. All mice were sacrificed on day 14 after parturition. Our results showed a significant decrease in serum levels of total protein and albumin, a marked hypoglycaemia and a significant decline in serum cholesterol and triglyceride levels in fluoride-treated mice and their pups. Whereas globulin and biluribin levels in serum were not significantly changed by NaF treatment. On the other hand, serum transaminase activities (aspartate transaminase; alanine transaminase), which well known as markers of liver function, were elevated indicating hepatic cells’ damage after treatment with fluoride. Lipid peroxidation increased in NaF-treated mice and pups, as revealed by high liver malondialdehyde levels, while serum total antioxidant status showed a significant decline. These biochemical modifications in NaF-treated mice also correspond histologically with extensive ballooning, hepatocellular necrosis and infiltration of mononuclear cells. These effects were not observed in controls. 相似文献
3.
The pathological picture of the migration phase of C. tenuicollis in pigs is characterized by a haemorrhagia within the liver parenchyma and under the liver surface. The haemorrhagia, which represents a migrational canal, is induced by the destruction of liver sinuses by migrating larvae. Approximately on day 10 p.i. a serofibrinous peritonitis occurs and free cysticerci appear in the exudate. On days 14-16 p.i. the exudative peritonitis may increase. The cysticerci are localized under the serosas or on them. On about day 10 p.i. even the pulmonary form of the disease may occur. On day 13 p.i. the cysticerci are present in the lumen of lung arteries or they migrate out of them. The changes in the lungs and on the pleura, as well as their dynamic changes, are identical with the changes in the liver and on the peritoneum. The period on days 21-24 p.i. is characterized by extensive synechiae of serosas and the cysticerci are firmly attached to the serosas. On day 35 p.i. the connective tissue adhesions persist and many of the cysticerci exhibit dystrophic changes or are dead and often already calcified. The wall of the pseudocyst, in which the cysticercus is situated, consists of the fibrocytes and serosa, and its cavity is not lined with endothelium, as it is the case in C. bovis and C. cellulosae. 相似文献
4.
A total of 26,478 ixodid ticks (935 pools) were examined by intracerebral inoculation of suckling mice. Six species of ticks were tested: Ixodes ricinus (23,470 individuals), I. trianguliceps (12), Haemaphysalis punctata (831), H. concinna (39), Dermacentor reticulatus (69) and D. marginatus (2,057). The ticks were collected largely by flagging vegetation, a substantial minority (4%) from animals. Three strains of Francisella tularensis were isolated, one each from I. ricinus (males, district Breclav, southern Moravia), D. reticulatus (males, district Breclav) and D. marginatus (engorged females collected from sheep in Roznava district, eastern Slovakia). D. marginatus and D. reticulatus represent new vector species for Czechoslovakia. 相似文献
5.
Kranti Mapuskar 《Pesticide biochemistry and physiology》2007,87(2):156-163
The experiment was conducted to study the after effects of administering DEP at different doses to female Swiss mice for a period of 90 days. Group I mice were fed on normal diet and water ad libitum. Group II mice were maintained on normal diet mixed with corn oil at 8.25 mg/kg of the diet/day as oil control. Group III, IV and V mice were given diethyl phthalate dissolved in corn oil mixed with the diet at 10, 25 and 50 mg/kg of the diet/day, which is approximately equal to 1.25, 3.125 and 6.25 mg/kg body weight/day. A significant dose dependent increase was observed in serum acid phosphatase (ACP) whereas, serum and liver triglycerides levels showed a significant increase only in the high-dose treated group. Significant dose-dependent increase in serum aspartate and alanine aminotransferase (AST and ALT) and liver glycogen was observed. Serum lactate dehydrogenase (LDH) was significantly increased only in 25 and 50 ppm DEP-treated mice. Liver cholesterol was significantly increased in all the treated groups. Liver histology by light microscopy showed intracellular vacuolations in all the treated groups which was much more evident in the 25 and 50 ppm DEP-treated mice while hepatocellular degeneration and hypertrophy of the hepatocytes was evident in 50 ppm DEP-treated mice. Proliferation of mitochondria and peroxisomes was evident in the electron micrographs of the 10 ppm DEP-treated mice while 25 and 50 ppm DEP-treated mice showed increase in lipid droplets and severe mitochondrial proliferation. 相似文献
6.
Marian Saeman Bleeke Martyn T. Smith John E. Casida 《Pesticide biochemistry and physiology》1985,23(1):123-130
Metribuzin was hepatotoxic in mice when administered intraperitoneally (ip) at sublethal doses of 150 to 250 mg/kg. Four dose-dependent abnormalities were evident. Histopathological examination revealed a fulminant centrilobular hepatic necrosis. The serum glutamic-pyruvic transaminase (GPT) activity was elevated. The liver glutathione (GSH) content was almost completely depleted. There was extensive covalent binding of radiocarbon from [carbonyl-14C]metribuzin to liver proteins and also high blood levels of metribuzin fragments. Each of these four effects of metribuzin on the liver or blood was alleviated or blocked in mice pretreated with piperonyl butoxide (PB), which inhibits the cytochrome P-450-dependent monooxygenase. PB also reduced the lethality of metribuzin by three-fold. In contrast, pretreatment with diethyl maleate to suppress the liver GSH content increased the lethality of metribuzin by twofold. The hepatotoxicity and acute lethality of metribuzin were probably due to reactive intermediates which are normally detoxified by GSH conjugation. The principal urinary metabolites of metribuzin in mice and rats are mercapturic acids, which arise via metribuzin sulfoxide or deaminometribuzin sulfoxide reacting with GSH. Sulfoxidation therefore appears to activate metribuzin to an electrophilic metabolite which, in the absence of GSH, binds to tissue proteins producing hepatotoxicity. 相似文献
7.
昆虫在某些发育阶段可感染不同种类的共生微生物,这些共生物在宿主生长、繁殖、适应环境及进化的过程中起重要作用。大量研究发现,昆虫体内的不同共生微生物并不是孤立存在和发生作用的,而是相互间不同程度地存在某些联系。本文以共生细菌为重点,综述了最近10多年来有关不同种共生细菌之间的关系,及共生细菌与其他昆虫相关微生物(病原细菌、真菌和病毒及昆虫共生真菌)之间相互关系的研究进展。其中,重点回顾了不同细菌在昆虫体内的共存和对宿主功能上的协作,昆虫中已经发生或可能正在发生的细菌取代,以及共生细菌对宿主的病原物敏感性的影响等方面的研究。最后对各种生物学技术大量应用于共生细菌研究的背景下此领域的研究前景进行了讨论。 相似文献
8.
Bacillary rickettsia-like organisms (BRLO) were found in the tick Dermacentor marginatus. They are gram-negative and differ from common bacteria and reckettsiae both in the cultivation conditions and morphology. BRLO are non-pathogenic for ticks and guinea pigs. In our studies they were isolated on half-engorged females of D. marginatus, on which they are still maintained. 相似文献
9.
ABSTRACT Forty bacterial strains isolated from leek blight (Allium porrum) in France and other countries were studied by conventional biochemical methods, serological reactions, numerical taxonomy, DNA-DNA hybridization, and ice nucleation activity, as well as by pathogenicity on leek and other host plants. They were compared with reference strains of Pseudomonas, mainly pathotype strains of P. syringae pathovars and strains of P. syringae pv. syringae isolated from various host plants including onions. Leek strains sorted with P. syringae species (sensu lato) by LOPAT tests (production of levan-sucrase, oxidase, pectinase, arginine dihydrolase, and hypersensitive reaction on tobacco). Leek strains were pathogenic to leek and produced symptoms identical to those observed in the field. They were the only strains in our study that could cause blight of leek. Thus, our results justify the creation of a new pathovar. Leek strains constituted a highly homogeneous DNA group and a discrete phenon by numerical taxonomy, and they belonged to O-serogroup POR. The name of P. syringae pv. porri is proposed for the bacterium causing leek blight. Criteria for routine identification are presented and taxonomic status is discussed. 相似文献
10.
Live-capture/recapture data on house mice caught in buildings on a single farm in England over a 1-year period showed that the populations were essentially unstable, being characterized by constant changes in size and composition. Less than 50% of the mice were recovered 8 weeks after they had been first captured. Although there was considerable individual variation in the movements of male and of female mice within particular buildings, movement between isolated populations was rare (6/439 animals; 1.4%). The house mouse was also found to be present in hedgerows near and distant to the farm buildings, albeit in low number. Movements of out-door living mice into farm buildings were not extensive, but could be important in relation to the re-invasion of cleared premises. The most abundant small rodent in the hedgerows was found to be Apodemus sylvaticus (L.). 相似文献
11.
R.E.J. Dyball 《Pesticide biochemistry and physiology》1982,17(1):42-47
The isolated rat neurophypophysis, which shows a calcium-dependent hormone release when depolarized in vitro was used as a model system to investigate the effects of the pyrethroids decamethrin and resmethrin on mammalian nervous tissue. Both compounds inhibited neurohypophysial hormone release in response to electrical stimulation, decamethrin being more potent than resmethrin. Decamethrin reduced the hormone content of the neurohypophysis. Resmethrin did not reduce stored hormone significantly and its effects on release were dose dependent. They could be mimicked by raising the [Na+] of the medium but not by lowering the [Ca2+]. Resmethrin had no effect on the release of hormone following depolarization of the tissue with a raised [K+]. The results are consistent with the suggestion that the compounds do not act on the potential-dependent secretion process but rather on the mechanism linking depolarization of the secretory terminals with the arrival of action potentials possibly by interfering with sodium-channel activation and inactivation. 相似文献
12.
解淀粉芽孢杆菌LJ1是从土壤中分离得到的1株对瓜类白粉病具有较好防效的细菌。为了解LJ1菌株对动物及人的安全性,测定了该菌株发酵液对实验鼠的急性毒性,以及处理后小鼠体内谷丙转氨酶(AST)、谷草转氨酶(ALT)和碱性磷酸酶(ALP)的含量及6种血相指标。结果发现:LJ1菌株发酵液对小鼠的急性经口毒性和对大鼠的急性经皮毒性均为"低毒"级(LD50>4 640 mg/kg); 处理3 d后,小鼠血清中AST、ALT和ALP 3种酶的含量及血液中白细胞、红细胞数和血红蛋白的含量均明显升高,与对照相比差异显著(P<0.05),14 d后各项指标基本恢复至正常水平,与对照无显著差异。说明LJ1发酵液灌胃处理初期对小鼠的脏器功能有一定影响,但14 d后其对脏器的影响可逐渐恢复。因此推断LJ1发酵液对动物机体安全,该菌株有进一步研究开发为生防菌的价值。 相似文献
13.
14.
放牧对典型草原土壤中几种生态因子影响的研究 总被引：5，自引：0，他引：5
研究了放牧强度对典型草原土壤中的微生物量氮、碳,微生物数量,五种酶活性和土壤理化性状的影响。结果表明:放牧对草原土壤中微生物量以及微生物数量的影响很显著,围栏和轻度放牧有利于保持或提高土壤中各类微生物数量,过度放牧则使土壤中的微生物量和微生物数量显著降低,同时,随放牧强度的增加,土壤的呼吸强度显著降低;轻度放牧使三类水解酶活性增加或极显著增加,中度和重度放牧导致此三类酶活性显著降低,不同程度的放牧均导致土壤中两类氧化酶活性增加;适度放牧有利于速磷的增加,而过度放牧则导致全磷、全氮和速效氮的显著降低。 相似文献
15.
F. A. Hakkaart Gusta Hartel 《European journal of plant pathology / European Foundation for Plant Pathology》1979,85(2):39-46
On the older leaves ofPelargonium zonale chlorotic rings and flecks are common, especially during spring and fall. From such plants an isometric virus can be isolated that causes local lesions on the leaves ofChenopodium quinoa. An attempt was made to produce symptomless plants, reacting negatively onC. quinoa. Meristem tips on a basal medium supplemented with α-naphthalene acetic acid and coconut milk produced abundant callus, but no plantlets. However, on media containing low concentrations of indole acetic acid and kinetin or benzyl adenine, some plants were produced that fulfilled the above requirements. Those selected on horticultural properties, are considered as valuable mother plants. Of twenty-one cultivars such plants were obtained. They may prove an important contribution to the improvement of theP. zonale industry in the Netherlands. 相似文献
16.
17.
L. Bos P. Grancini 《European journal of plant pathology / European Foundation for Plant Pathology》1965,71(1):1-2
Witches' broom phenomena (witches' broom growth + antholysis) observed inTropaeolum majus and in clovers in the Netherlands and in several wild and cultivated plants in Italy were demonstrated to be due to virus infection. The virus(es) could be transmitted by grafting, through dodder and by means of leaf-hoppers (Euscelis spp. primarily). The virus isolates found in both countries did not differ appreciably in the symptoms they caused. Many of the deviations concerned have been known for a long time as teratological phenomena. In the extensive literature considerable confusion exists concerning the identity of several witches' broom virus diseases. They constitute a good example of the problem of virus variability. A continuous splitting of witches' broom viruses on the basis of slight differences in symptom expression or of vector specificity does not seem justified. Since no intrinsic properties of the virus(es) concerned are known, the only conclusion that can be drawn from the information available is that the Dutch and the Italian isolates show a great similarity to aster yellows virus as well as to tomato big bud, stolbur and other witches' broom viruses. 相似文献
18.
Plant disease epidemiology requires expansion of its current methodological and theoretical underpinnings in order to produce full contributions to global food security and global changes. Here, we outline a framework which we applied to farmers' field survey data set on rice diseases in the tropical and subtropical lowlands of Asia. Crop health risks arise from individual diseases, as well as their combinations in syndromes. Four key drivers of agricultural change were examined: labor, water, fertilizer, and land availability that translate into crop establishment method, water shortage, fertilizer input, and fallow period duration, respectively, as well as their combinations in production situations. Various statistical approaches, within a hierarchical structure, proceeding from higher levels of hierarchy (production situations and disease syndromes) to lower ones (individual components of production situations and individual diseases) were used. These analyses showed that (i) production situations, as wholes, represent very large risk factors (positive or negative) for occurrence of disease syndromes; (ii) production situations are strong risk factors for individual diseases; (iii) drivers of agricultural change represent strong risk factors of disease syndromes; and (iv) drivers of change, taken individually, represent small but significant risk factors for individual diseases. The latter analysis indicates that different diseases are positively or negatively associated with shifts in these drivers. We also report scenario analyses, in which drivers of agricultural change are varied in response to possible climate and global changes, generating predictions of shifts in rice health risks. The overall set of analyses emphasizes the need for large-scale ground data to define research priorities for plant protection in rapidly evolving contexts. They illustrate how a structured theoretical framework can be used to analyze emergent features of agronomic and socioecological systems. We suggest that the concept of "disease syndrome" can be borrowed in botanical epidemiology from public health to emphasize a holistic view of disease in shifting production situations in combination with the conventional, individual disease-centered perspective. 相似文献
19.
《Physiological and Molecular Plant Pathology》2008,72(4-6):126-134
Plant innate immunity relies on specialised immune receptors that can detect and defend against a wide variety of microbes. The first group of receptors comprises the transmembrane pathogen- or pattern-recognition receptors (PRRs), which respond to slowly evolving pathogen- or microbe-associated molecular patterns (PAMPs/MAMPs). The second group of immune receptors is formed by the polymorphic disease resistance (R) proteins that detect microbe-derived effector proteins. Most R proteins are members of the nucleotide binding leucine-rich repeat (NB-LRR) class. Although this class comprises one of the biggest protein families in plants, relatively few have been functionally characterised to date. The question rises whether all NB-LRRs function as immune receptors, or that they might have alternative functions. The answer is: yes, they do have alternative functions that are different from the immune receptor function. This review summarises the current knowledge about non-immune receptor signal transduction functions of NB-LRRs in plants. 相似文献
20.
浙江省大、小麦致病腐霉的研究 总被引：1，自引：0，他引：1
1989年11月~1990年3月,从浙江省不同地区的大麦(浙农大5号)、小麦(浙麦3号)以及麦田土壤中,分离鉴定到Pythium.dissotocum,P.irregulare,P.polypapillatum(国内新记录),P.spinosum和P.ultimum等5种腐霉。接种试验表明,分离到的5种腐霉对供试大、小麦都能致病,引起根腐、根尖变褐和坏死、第一片叶卷曲,抑制植株生长,造成植株各部不同程度的矮化和变短。 相似文献