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11.
Temperatures from 13°C to 30°C had no significant effect on the formation of shoots on root segments of Rubus procerus P. J. Muell. Shoots were not produced at 8°C. Some new roots were produced on root segments at all temperatures between 8°C and 30°C, although significantly more (P= 0·05) roots were produced at 26°C. The polarity of the root system was maintained in root segments. More shoots were formed towards the basal end, i.e. nearest the crown, and more roots towards the apical end of the root segments.  相似文献   
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A phytotoxic protein that evokes the typical symptoms of Verticillium wilt disease in seedlings of Gossypium hirsutum L. (Upland cotton) was isolated from culture filtrates of Verticillium dahliae. The protein was purified by ammonium sulfate precipitation, Sephadex-G100 fractionation, and native PAGE. The 18.5 kDa protein, designated VD18.5, appears to be a single subunit protein with an isoelectric point between 3 and 5. VD18.5 induces symptoms of leaf dehydration, chlorosis, necrosis and stem discoloration in seedlings of the disease susceptible cotton cultivar Siokra 1–4. The LD50 of VD18.5 on protoplasts of Siokra 1–4 was 18 μg mL−1. VD18.5 had no noticeable effect on Pima S-7, which is a disease resistant cultivar. Phytotoxic activity was partially destroyed at high temperature and was abolished by digestion with proteinase K. Mass spectrometry fingerprinting and protein sequence data from VD18.5 yielded no significant matches when submitted to the Mascot search engine and NCBI non-redundant protein databases, respectively. These results suggest that VD18.5 is a novel protein that may be involved in the development of some of the symptoms associated with Verticillium wilt disease in the cotton plant.  相似文献   
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Phytophthora cinnamomi is an ecologically and economically important pathogen. In this study, PCR assays were developed with primer pair LPV2 or LPV3 for rapid detection and identification of this organism. Both primer pairs were selected from putative storage protein genes. The specificity of these primer pairs was evaluated against 49 isolates of P. cinnamomi , 102 isolates from 30 other Phytophthora spp., 17 isolates from nine Pythium spp. and 43 isolates of other water moulds, bacteria and true fungi. PCR with both primer pairs amplified the DNA from all isolates of P. cinnamomi regardless of origin. The LPV3 primers showed adequate specificity among all other species tested. The LPV2 primers cross-reacted with some species of Pythium and true fungi, but not with any other Phytophthora species. PCR with the LPV3 primers detected the pathogen at levels of a single chlamydospore or 10 zoospores in repeated tests. The PCR assay was at least 10 times more sensitive than the plating method for detection of the pathogen from artificially infested soilless medium, and, to a lesser extent, from naturally infected plants. PCR with LPV3 primers can be a useful tool for detecting P. cinnamomi from soilless media and plant tissues at ornamental nurseries, whereas the LPV2 primers can be an effective alternative for identification of this species from pure culture. Applications of these assays for detection of P. cinnamomi in other environments were also discussed.  相似文献   
14.
This article provides a source for easy reference, summarizing in one location newly recognized and unusual causes of acute renal failure (ARF) in dogs and cats. Several of the causes discussed in this article have been described previously. New or unusual causes of ARF in dogs and cats include infectious diseases (leptospirosis,borreliosis, and babesiosis), nephrotoxicants (aminoglycosides,vitamin D, and nonsteroidal anti-inflammatory drugs), and plant material (lilies and raisins/grapes).  相似文献   
15.
The majority of information on oncology therapies has been reported in humans, canine, and feline patients, and laboratory animals with experimentally induced tumors. A variety of treatments,including radiation therapy, chemotherapy, photodynamic therapy, and others have been used with exotic animals. There are many species of exotic pets, and anatomic differences, as well as husbandry and nutritional requirements, must be taken into account to provide optimal care. By providing a broad overview of therapies and considerations for treatment, this article is intended to provide the practitioner with an overview of approach and options when addressing oncology cases in exotic animals.  相似文献   
16.
The cumulative cardiotoxicity that occurs as a result of doxorubicin chemotherapy is irreversible and can affect both quality and quantity of life for the cancer patient. Cardiac troponin I (cTnI) is a sensitive and specific marker of cardiomyocyte death. The purpose of this retrospective study was to evaluate serum concentrations of cTnI in dogs with lymphoma or osteosarcoma given doxorubicin chemotherapy, and with known cardiac outcome, based on a minimum assessment by physical examination and thoracic radiography. Serum samples were also available for cTnI measurement from seven healthy dogs given intracoronary doxorubicin. Serial serum samples obtained before, during and after doxorubicin chemotherapy showed increased cTnI concentrations in some clinical patients following chemotherapy (P = 0.0083 compared to baseline), but this did not correlate with clinical signs of cardiomyopathy. In dogs that subsequently developed cardiomyopathy however, serum cTnI concentrations were elevated before clinical signs became evident (confirmed with echocardiography).  相似文献   
17.
C-reactive protein concentrations in canine acute pancreatitis   总被引:1,自引:0,他引:1  
Objective: To determine if C‐reactive protein (CRP) concentration is elevated in spontaneously occurring canine acute pancreatitis (AP), and to measure changes in CRP during the course of hospitalization. Design: Prospective study. Setting: Tufts University School of Veterinary Medicine Foster Hospital for Small Animals. Animals: Sixteen client‐owned dogs with AP and 16 healthy controls. Interventions: Blood samples were obtained from the AP group on the day of diagnosis (Day 1), and on Days 3 and 5, unless the dog died or was discharged from the hospital. Blood was obtained from the control dogs once. Measurements and main results: Serum CRP was measured using a commercial immunoassay for each dog with AP and for healthy controls. Day 1 CRP concentrations were significantly higher in the AP group (56.1±12.7 μg/mL) compared with controls (2.8±1.3 μg/mL; P<0.001). For the 7 dogs that had samples collected on all 3 days, the mean CRP concentrations decreased significantly (P=0.043) over the 5 days of measurement. Of the 16 dogs with AP, 14 were discharged from the hospital and 2 were euthanized. Conclusions: Serum CRP concentrations were elevated in this group of 16 dogs with spontaneously occurring AP. In the 7 dogs that had measurements on all 3 days, the mean CRP concentration decreased from the day of diagnosis to the measurement made 5 days later.  相似文献   
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A 20‐month‐old female spayed Staffordshire Terrier (22.3 kg) presented to the Orthopedic Surgery Service at North Carolina State University Veterinary Teaching Hospital for evaluation of a 6‐week history of toe‐touching to nonweight‐bearing lameness in the right hind limb. Radiographs of the right stifle revealed a multiloculated lytic lesion of the distal femur, with a large open lytic zone centrally, numerous osseous septations peripherally, and focal areas of cortical thinning and loss. An aspirate of the right distal femoral lesion yielded mildly cloudy serosanguineous fluid. Cytologic examination of the fluid revealed a pleomorphic population of discrete cells that exhibited marked anisocytosis and anisokaryosis and a variable nuclear‐to‐cytoplasmic (N:C) ratio, which were interpreted as probable neoplastic cells, with few macrophages, and evidence of hemorrhage. Given the clinical signs of pain, lesion size, and concern for malignant neoplasia, amputation of the right hind limb was performed. Histologically, the lesion had undulating walls 1‐3 mm thick with a continuous outer layer of dense fibrous tissue and an inner layer composed of reactive cancellous bone with no cortical compacta remaining. Remnants of thin fibrous or fibro‐osseous septa projected from the bony wall into the cyst lumen. The final histologic diagnosis was a benign multiloculated solitary (unicameral) bone cyst of the distal right femur. Based on the histopathologic findings, it was speculated that the cells identified on cytology were a mixture of developing osteoclasts, osteoblasts, endothelial, and stromal cells. This is the first report describing the cytologic examination of a solitary bone cyst in veterinary medicine.  相似文献   
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