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141.
Franco Barbieri Claudio Colosio Helmut Schlitt Marco Maroni 《Pest management science》1995,43(4):259-262
The pharmacokinetics of pentachlorophenol (PCP) excretion in urine was examined in four workers exposed to the biocide in the tannery and wood industries. PCP concentration in urine was significantly higher in morning samples than in afternoon or evening samples. This excretion pattern was observed during an exposure of several shifts and following a four-week holiday period. The estimated half-life for PCP urine excretion was 10 days. Biological monitoring of occupational exposure to PCP should be carried out by measuring the concentration of the compound in urine collected in the morning or before the workshift. 相似文献
142.
Hübner SO Oliveira AP Franco AC Esteves PA Silva AD Spilki FR Rijsewijk FA Roehe PM 《Comparative immunology, microbiology and infectious diseases》2005,28(3):187-196
In this work, a role for the genes encoding glycoproteins I (gI) and E (gE) and the US9 protein of bovine herpesvirus type 5 (BHV-5) in neuropathogenicity and reactivation of latent infections was examined. Calves infected intranasally with a gI/gE/US9 deleted recombinant shed up to 10(2.85) TCID50/ml infectious virus in nasal secretions. Calves infected with the wild type BHV-5 parental virus shed up to 10(5) TCID50/ml virus. No signs of disease were observed in calves infected with the recombinant virus, whereas those infected with wild type virus displayed respiratory and neurological signs. The recombinant was only able to reach the basal portions of the central nervous system. In contrast, wild type virus was found widespread within the brain. Reactivation with dexamethasone 60 days post-infection resulted in reactivation of wild type virus, whereas the recombinant virus could not be reactivated. These studies demonstrate that genes gI, gE and US9 of BHV-5 are important for its neuropathogenicity and its ability to reactive from latency. 相似文献
143.
Pepe M Gialletti R Moriconi F Puccetti M Nannarone S Singer ER 《Veterinary surgery : VS》2005,34(3):260-264
OBJECTIVE: To describe a laparoscopic technique for sterilization of the male donkey using an endoscopic linear stapler (ELS). STUDY DESIGN: Clinical report. ANIMALS: Male Sardinia donkeys (n=6), aged 24-36 months. METHODS: Laparoscopic sterilization was performed under standing sedation or recumbent under general anesthesia. An endoscopic linear stapler was used to transect, and control hemorrhage of, the spermatic cord. Serum testosterone concentrations were measured preoperatively and at 3, 6, and 12 months after sterilization. One testis from each of 2 donkeys was collected at 12 months for histologic examination. RESULTS: Sterilization was successfully achieved. The only minor intraoperative complication experienced was hemorrhage from 1 spermatic cord stump, which was re-stapled. No other major short- or long-term complications occurred. Serum testosterone concentrations were < 15 ng/dL at 3, 6, and 12 months after surgery in all donkeys. Testicular atrophy without evidence of revascularization was observed in the 2 testes examined histologically. CONCLUSIONS: Sterilization of descended testes by intraabdominal laparoscopic transection of the spermatic cord is a simple practical method, with minimal intraoperative or postoperative complications. Testicular revascularization did not occur. CLINICAL RELEVANCE: Laparoscopic sterilization in donkey can be performed using an endoscopic linear stapler as an alternative to scrotal castration. 相似文献
144.
José?Carlos?Franco Pompeo?Suma Elsa?Borges?da?Silva Daniel?Blumberg Zvi?MendelEmail author 《Phytoparasitica》2004,32(5):507-522
Six mealybug species have been reported as citrus pests in the Mediterranean Basin: the citrus mealybugPlanococcus citri (Risso), the citriculus mealybugPseudococcus cryptus Hempel, the longtailed mealybugPseudococcus longispinus (Targioni-Tozzetti), the citrophilus mealybugPseudococcus calceolariae (Maskell), the obscure mealybugPseudococcus viburni (Signoret) and the spherical mealybugNipaecoccus viridis (Newstead). Some of these species,e.g. N. viridis, have recently been introduced into the region and are still spreading. Mealybugs are usually occasional or minor pests of
citrus, but some species can reach key pest status. Mealybug management strategies in citrus have been based mostly on classical
biological control and, to a lesser extent, on augmentative releases. However, chemical control is widely used, mainly because
of the poor adaptation of the principal natural enemies to the climatic conditions of the Mediterranean. The application of
pheromones is still restricted to monitoring the citrus mealybug, whose sex pheromone is commercially available. Mass trapping
and mating disruption should be considered for possible use in IPM programs as an alternative method to supplementary chemical
treatments. Enhancement of biological control through management of ant populations is another promising tactic for control
of mealybugs. Strategies for managing mealybug pests of citrus, and possible levels of integration of different tactics according
to the pest status, are discussed.
http://www.phytoparasitica.org posting Oct. 3, 2004. 相似文献
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146.
The inhibitory effect of three proteinaceous inhibitors isolated from little and finger millet was examined on gut α-amylases for four stored grain and four phytophagous insect-pests. Additionally, using native PAGE, several α-amylases isozymes were observed in all insect-pests studied. Furthermore, thermostabilities and the pH optimum for insect-pests α-amylases, which varied from acidic to alkaline, were also determined. On the other hand, proteinaceous inhibitors from little millet seeds Panicum sumatrense (LMCO3) and from finger millet (FMCO11 and FMCO13) inhibited insect-pests α-amylases with different proportions. The highest inhibition percent was recorded for LMCO3 and FMCO13 against Callosobruchus chinensis α-amylase, where the inhibition percent was approximately 70 and 50%, respectively. Furthermore, millet α-amylase inhibitors also reduced significantly digestive α-amylolytic activities of Acaea janata, C. cephalonica, Sitophilus oryzae, and Tribolium castaneum, indicating that these α-amylase inhibitors could be used toward crop insect-pests. 相似文献
147.
An in vitro culture system was used to study the influence of gravity on axillary shoot formation and adventitious root regeneration in Mentha piperita L. The direction of the gravity vector was altered by displacing stem node explants in different orientations. Also, microgravity conditions were simulated by rotating the explants on a horizontal clinostat so that the main axis of nodes was either parallel (Cpa) or perpendicular to the clinostat axis (Ccp and Ccf, centripetally and centrifugally oriented, respectively). Mint nodes were cultured on solidified Linsmaier and Skoog's medium [Physiol. Plant. 18 (1965) 100] adding a filter-sterilized aqueous solution of 2 mg/l benzyladenine (BA) in half of the cultures. The proliferation of axillary shoots as well as adventitious root formation were not affected by altering upright explant orientation. On the contrary clinorotation was able to modify plantlet development. In absence of BA, leaf width was hindered by Cpa treatment and penultimate internode length was enhanced by Ccp. Furthermore, a negative effect of Cpa treatment was observed in root length parameter, while Ccp increased the root number both in absence and in presence of BA. An effect strictly connected to clinorotation in presence of BA was the occurrence of hyperhydricity. Moreover, explants under clinorotation treatments switched their gravitropic response modifying shoot curvature. 相似文献
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150.
Marta Vascellari Silvia Tasca Tommaso Furlanello Erika Carli Carlo Patron Franco Mutinelli Marco Caldin 《Journal of veterinary diagnostic investigation》2007,19(2):205-208
An unusual clinical presentation of lymphoma with vertebral involvement in a dog is reported. A 20-month-old intact female Golden Retriever presented with progressive paraparesis and anorexia. Complete blood count and serum biochemistry profile demonstrated pancytopenia and hypercalcemia. Ventral fusion of the lumbar vertebrae by new bony tissue deposition was evident on X-ray and CT scan. Fine needle aspiration revealed neoplastic lymphoid cells in lymph nodes and bone marrow. Histologically, vertebral bone and osteophytes, liver, bone marrow, kidney, and lymph nodes were diffusely infiltrated by neoplastic, lymphoid cells, with scant cytoplasm and round hyperchromatic nuclei. Polyostotic and medullary T-cell lymphoma with spondylosis was diagnosed. Lymphoma mainly affecting bone is uncommon in the dog. The present case differs from previously described polyostotic lymphomas in clinical signs of the disease, mainly attributable to spondylarthrosis. In addition, lymphomatous proliferation was associated with osteoproductive lesions of the vertebrae. 相似文献