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971.
OBJECTIVE: To evaluate quality of duodenal tissue specimens obtained endoscopically from dogs and cats and submitted to 1 of 2 diagnostic laboratories for evaluation. DESIGN: Case series. SAMPLE POPULATION: Slides from 50 consecutive canine and 50 consecutive feline endoscopically obtained duodenal tissue specimens submitted to laboratory 1 and 49 consecutive canine and 46 consecutive feline specimens submitted to laboratory 2. PROCEDURE: Slides were examined independently by 3 investigators, and each tissue piece on each slide was classified as clearly inadequate, questionable, or clearly adequate on the basis of 4 criteria. An overall score was then assigned to the slide. RESULTS: Slides from laboratory 1 were more likely to be scored as clearly adequate and less likely to be scored as clearly inadequate than slides from laboratory 2. Clearly adequate slides from laboratory 1 had a higher number of clearly adequate pieces of tissue than did clearly adequate slides from laboratory 2. Slides scored as clearly adequate had a higher number of individual tissue pieces than did slides scored as clearly inadequate. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the quality of endoscopically obtained duodenal tissue specimens submitted to laboratories can vary, possibly because of differences in experience of individuals collecting biopsy specimens. Results suggest that at least 8 individual tissue pieces should be submitted when performing endoscopic biopsy of the duodenum in dogs and cats.  相似文献   
972.
Few studies have been carried out for the prevalence of canine echinococcosis in Mongolia. This study was designed to elucidate a preliminary information of the prevalence from feces collected in the field. Sixty-seven fecal samples from dogs and 2 red foxes in Altai town were collected and examined for Echinococcus coproantigen and eggs. Coproantigen detection was performed by a sandwich ELISA using a monoclonal antibody EmA9 raised against Echinococcus multilocularis somatic antigen. Of the dog samples examined, 17 (25.4%) were positive by the ELISA. One out of two foxes was positive, too. Taeniid egg-positive feces were recognized in 12 dog feces. Only 6 samples were both coproantigen and egg positive. Eggs of Ancylostoma sp., Trichuris sp.; and Capillaria sp.; were also registered.  相似文献   
973.
974.
A circulating anticoagulant was detected in a 2-year-old Chesapeake Bay Retriever with hemolytic anemia, nephrotic syndrome, thrombocytopenia, polyarthropathy, and pulmonary thromboembolism. A persistent prolongation of the activated partial thromboplastin time (aPTT) was detected, and it did not correct with repeated administration of fresh frozen plasma. The aPTT was still prolonged, with a 1:1 mixture of patient's plasma and normal dog plasma in vitro, suggesting the presence of a circulating inhibitor. Results of assays to characterize the inhibitor were compatible with those described for the lupus anticoagulant in human patients with systemic lupus erythematosus. Paradoxically, patients having the lupus anticoagulant are at increased risk for thrombosis. Pulmonary thromboembolism has been described as a frequent complication of immune-mediated hemolytic anemia in the dog, and the presence of a circulating anticoagulant should be considered as a potential mechanism.  相似文献   
975.
Bobwhite quails (Colinus virginianus) were inoculated with 10(6) mean tissue-culture infective dose of quail bronchitis virus at 1, 3, 6, or 9 weeks of age by intratracheal, intraperitoneal, or subcutaneous routes. Quails developed necrotizing tracheitis, proliferative and necrotizing bronchitis and pneumonia; multifocal necrotizing hepatitis; necrotizing splenitis, with or without hyperplasia of splenic mononuclear phagocytes; bursal lymphoid necrosis; and bursal atrophy. Lesions were more extensive and severe in quails inoculated at 1 or 3 weeks of age than in older quails. Large intranuclear inclusions, characteristic of adenovirus infection, were identified in trachea, lung, liver, and bursa of Fabricius. This is the first report of the histopathology of experimentally induced quail bronchitis.  相似文献   
976.
977.
φRSM1 and φRSM3 (φRSM phages) are filamentous phages (inoviruses) that infect Ralstonia solanacearum, the causative agent of bacterial wilt. Infection by φRSM phages causes several cultural and physiological changes to host cells, especially loss of virulence. In this study, we characterized changes related to the virulence in φRSM3-infected cells, including (i) reduced twitching motility and reduced amounts of type IV pili (Tfp), (ii) lower levels of β-1,4-endoglucanase (Egl) activity and extracellular polysaccharides (EPS) production, and (iii) reduced expression of certain genes (egl, pehC, phcA, phcB, pilT, and hrpB). The significantly lower levels of phcA and phcB expression in φRSM3-infected cells suggested that functional PhcA was insufficient to activate many virulence genes. Tomato plants injected with φRSM3-infected cells of different R. solanacearum strains did not show wilting symptoms. The virulence and virulence factors were restored when φRSM3-encoded orf15, the gene for a putative repressor-like protein, was disrupted. Expression levels of phcA as well as other virulence-related genes in φRSM3-ΔORF15-infected cells were comparable with those in wild-type cells, suggesting that orf15 of φRSM3 may repress phcA and, consequently, result in loss of virulence.  相似文献   
978.
Field studies were conducted at Alupe in western Kenya in 1995 and 1996 to evaluate the efficacy of crop and species mixtures for the management of sorghum anthracnose (caused by Colletotrichum sublineolum) and leaf blight (caused by Exserohilum turcicum). The progress of these diseases developing simultaneously on a susceptible sorghum cultivar planted in inter- or intra-row mixtures of varying proportions with either maize or resistant sorghum was monitored. The effects of host type and mixture patterns on disease progress were compared by parameter estimates derived from fitted Lotka-Volterra competition equations and nonlinear logistic models. Competition coefficients were not significant and their confidence intervals included zero in most cases, suggesting that interactions between C. sublineolum and E. turcicum did not occur. Mixtures of the susceptible sorghum with either the nonhost maize or the resistant sorghum delayed the time when disease is first observed and reduced the rate of disease progress and carrying capacity for both anthracnose and leaf blight, with a more pronounced effect on the latter disease. The lower efficacy of mixtures in reducing anthracnose was attributed to an aggregated spatial pattern, coupled with higher rates of progress for this disease. Intra-row mixtures were more efficient than inter-row mixtures in reducing disease development in all years. The implications of these observations for the management of sorghum diseases under small-scale farming systems are discussed.  相似文献   
979.
Summary The polypeptide composition of Fraction-1-Protein (F1P) from rice × sorghum, rice × wheat hybrids and their respective parents have been analyzed by a microelectrofocusing method. The large sub-unit (LSU) is composed of three polypeptides and the small sub-unit (SSU) of two polypeptides in rice and sorghum parents and rice × sorghum hybrids. Similarly, LSU is composed of three polypeptides in the rice and wheat parents and rice × wheat hybrids. Two polypeptides occur in the SSU of rice parent and rice × wheat hybrids where as only one polypeptide in the wheat parent. These polypeptides also differ in their isoelectric points. Based on the previous reports of F1P inheritance in hybrids in other crops, F1P analysis of rice × sorghum and rice × wheat hybrids does not seem to be an important marker to identify such intergeneric hybrids. Since this is first such report of F1P inheritance in hybrids between distantly related plants, its implication in different modes of inheritance are discussed.Abbreviations F1P Fraction-1-Protein - IEF Isoelectric focusing - pI Isoelectric points - LSU Large sub-unit - RuBPCase Ribulose 1,5-Bisphosphate Carboxylase-oxygenase - SSU Small sub-unit  相似文献   
980.
Supply of 0.01 to 1.0 mM Cd acetates either to the intact seedlings or to the excised leaves of 15 dPisum sativum L. Cv. Bonvilla seedlings inhibitedin vivo nitrate reductase activity (NRA), total soluble protein, chlorophyll, and carotenoids. The inhibition was independent of metal concentrations. In excised leaf tissues, higher concentrations (0.5 to 1.0 mM) of Cd had no conspicuous effect on nitrate assimilation. When NRA was assayed byin vitro method, an increase of 12 to 45% was obtained with Cd in intact and excised leaves. It appears that NRA is more sensitive to Cd concentration than any other parameter examined.  相似文献   
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