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1.
Journal of Crop Science and Biotechnology - The cultivation of sweet corn is expanding in Brazil, but there are serious constraints about the availability of commercial cultivars. The selection of...  相似文献   
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Recombinant canine granulocyte colony-stimulating factor (rcG-CSF) was administered to clinically normal dogs, cyclic-hematopoietic dogs, and dogs undergoing autologous bone marrow transplantation, to determine whether rcG-CSF could be used to stimulate WBC production and function in normal and neutropenic dogs. To the normal dogs, rcG-CSF was administered by SC injection at rates of 1 microgram/kg of body weight, q 12 h; 2 micrograms/kg, q 12 h; or 5 micrograms/kg, q 12 h. A significant dose-dependent increase in the WBC count resulted from the stimulation of bone marrow progenitor cells. The increased WBC count was characterized by mature neutrophilia and monocytosis. Neutrophil myeloperoxidase and phagocytic activity were normal in rcG-CSF-treated normal dogs, demonstrating the production of normal functional neutrophils in response to rcG-CSF treatment. Recombinant canine G-CSF prevented neutropenia and associated clinical signs but did not completely eliminate the cycling of neutrophils in cyclic-hematopoietic dogs when it was administered at rates of 1 microgram/kg, q 12 h, and 2.5 micrograms/kg, q 12 h. The time to bone marrow reconstitution was not decreased in dogs treated with rcG-CSF at a rate of 2.5 micrograms/kg, q 12 h, for 13 days following autologous bone marrow transplantation. On the basis of our findings, we suggest that treatment with rcG-CSF is an effective way to stimulate myelopoiesis in dogs, but that the dose of rcG-CSF required to stimulate WBC production will vary depending on the cause of neutropenia. Recombinant canine G-CSF should be useful in stimulating production and maintaining function of WBC for treatment of clinical diseases seen commonly in veterinary practice.  相似文献   
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Torsion of abdominal organs in sows: a report of 36 cases   总被引:3,自引:3,他引:0       下载免费PDF全文
Necropsy records of 36 sows with torsion of abdominal organs involving individually the stomach, the spleen, a liver lobe or the intestine were reviewed for the years 1970 to 1983, and the age, the clinical signs and the gross lesions were recorded. These acute abdominal accidents were characterized clinically by sudden death. Dry sows from large breeding units were affected. Twenty-six cases were diagnosed between January 1981 and December 1983 while only ten cases had been seen between 1970 and 1980. Gastric torsion was the most common condition (40% of the cases) and the other three conditions were equally represented (20% each). Management practises that could be responsible for the apparent increase in occurrence of this problem are discussed.  相似文献   
5.
A transitional cell carcinoma of the urinary bladder was found in a beluga whale stranded in the St. Lawrence middle estuary. Various organs of this animal were submitted to high resolution gas chromatography coupled with mass spectrometry analysis. High frequency of urinary bladder cancer in the human population of the same area and the presence of carcinogenic compounds in the marine environment of this animal are discussed.

Concurrent isolation of Edwardsiella tarda from various organs of this whale is also reported.

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Summary On two occasions an anaplasm was isolated from sheep on the Dutch island of Ameland. The organism proved to be highly pathogenic for splenectomised sheep; a non-splenectomised animal recovered spontaneously after the packed cell volume had decreased by 40%. Treatment with oxytetracycline was effective. Its pathogenicity for goats appeared to be low, and the organism was apparently not infective to splenectomised cattle. This anaplasm differs from Anaplasma ovis in that less than 30% of the organisms are marginally situated in the red cell, as against over 70% in A. ovis; cross-immunity with A. ovis was incomplete and the latter appeared to be far more pathogenic to goats than the Dutch anaplasm, for which the name Anaplasma mesaeterum sp.n. is proposed. Its ultrastructure is similar to that of A. marginale and A. ovis. The vector is either Ixodes ricinus or Haemaphysalis punctata. Its practical importance remains to be ascertained.  相似文献   
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An indirect "sandwich" enzyme-linked immunosorbent assay (ELISA) using polyvalent and monovalent antisera was compared with the 50% complement fixation (CF50) test for the detection of foot-and-mouth disease (FMD) O, A, and C virus types. ELISA was more sensitive than CF50 tests when polyvalent antisera were used for detecting the 3 types of virus in epithelial samples, whereas ELISA using monovalent antisera was the least sensitive technique. The ELISA performed with polyvalent antisera was 9 times more sensitive for detecting FMD virus than that with monovalent antisera. However, viral isolation in cell culture was the most sensitive detection system. The combined use of ELISA with polyvalent antisera and cell culture inoculations was the most effective procedure for identifying FMD virus in epithelial samples from the field.  相似文献   
8.
The fungal pathogenPhytophthora infestans is the causal organism of late blight, one of the most devastating diseases of potato. In the past, various aspects of the potato-P. infestans interaction have been studied extensively. In this paper we briefly review the current knowledge of the molecular events associated with the interaction and in addition we discuss a new approach for analyzing the molecular basis of pathogenicity ofP. infestans.  相似文献   
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Introduction:  Cyclooxygenase‐2 (Cox‐2) is the inducible form and the rate‐limiting enzyme, for conversion of arachidonic acid to prostaglandins. Cox‐2 overexpression, common in carcinomas, is associated with increased growth rate, resistance to apoptosis, angiogenesis, and overall, both local and distant aggressive behavior. Cox‐2 overexpression has been detected in human and canine mammary tumors (MTs). Histopathology of canine MT is not always predictive of biologic behavior, and anecdotally, only 50% of the malignant MTs are expected to metastasize. We hypothesize that Cox‐2 expression correlates with aggressive behavior.
Methods:  This retrospective study evaluated 48 bitches, presented for excision of MT between 2000 and 2003 at FMVZ de Botucatu‐UNESP, Brasil. Follow‐up varied from 18 months to 24 months and included physical examination and thoracic radiographs. Histopathologic examination was performed in all tumors, as well as in metastatic lesions when detected in the follow‐up period. Immunohistochemistry was used to detect expression of Cox‐2 in paraffin blocks (Rabbit polyclonal anti‐PGHS‐2. Oxford Biomedical). 10 adenomas, 10 carcinomas, 10 benign mixed tumors, 10 malignant mixed tumors and 8 cases of primary carcinomas and their metastatic lesions.
Results:  Expression of Cox‐2 varied among groups. Adenomas (32.1%), mixed benign tumors (38%), carcinomas (60.3%), malignant mixed tumors (65.8%), and metastatic carcinomas (81.25%) and their metastatic lesions (84.35%). Statistically significant differences (p < 0.05) were observed between the benign and malignant counterparts and between carcinomas and metastatic carcinomas.
Conclusions:  Cox‐2 expression correlates with both histologic and biologic behavior in mammary carcinomas, and may serve as a predictor of metastatic potential.  相似文献   
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