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971.
D. J. James A. J. Passey M. A. Easterbrook M. G. Solomon D. J. Barbara 《Phytoparasitica》1992,20(Z1):S83-S87
Using a leaf disc transformation procedure andAgrobacterium- mediated gene transfer, transgenic apple and strawberry plants have been produced that carry a gene encoding a cowpea trypsin
inhibitor (CpTl). This gene is known to confer resistance to several lepidopteran and coleopteran insect pests. Scientific
and regulatory aspects of this type of work are discussed. 相似文献
972.
973.
Lemke KA Runyon CL Horney BS 《Journal of the American Veterinary Medical Association》2002,220(12):1818-1822
OBJECTIVE: To determine effects of preoperative administration of ketoprofen on whole blood platelet aggregation, buccal mucosal bleeding time, and hematologic indices in dogs after elective ovariohysterectomy. DESIGN: Randomized, masked clinical trial. ANIMALS: 22 healthy dogs. PROCEDURE: 60 minutes before induction of anesthesia, 11 dogs were given 0.9% NaCl solution (control), and 11 dogs were given ketoprofen (2 mg/kg [0.9 mg/lb], IM). Thirty minutes before induction of anesthesia, glycopyrrolate (0.01mg/kg [0.005 mg/lb]), acepromazine (0.05 mg/kg [0.02 mg/lb]), and butorphanol (0.2 mg/kg 10.09 mg/lb]) were given IM to all dogs. Anesthesia was induced with thiopental (5 to 10 mg/kg [2.3 to 4.5 mg/lb], IV) and maintained with isoflurane (1 to 3%). Ovariohysterectomy was performed and butorphanol (0.1 mg/kg [0.05 mg/lb], IV) was given 15 minutes before completion of surgery. Blood samples for measurement of variables were collected at intervals before and after surgery. RESULTS: In dogs given ketoprofen, platelet aggregation was decreased 95 +/- 10% and 80 +/- 35% (mean +/- SD) immediately after surgery and 24 hours after surgery, respectively, compared with preoperative values. At both times, mean values in dogs given ketoprofen differed significantly from those in control dogs. Significant differences between groups were not observed for mucosal bleeding time or hematologic indices. CONCLUSIONS AND CLINICAL RELEVANCE: Preoperative administration of ketoprofen inhibited platelet aggre gation but did not alter bleeding time. Ketoprofen can be given before surgery to healthy dogs undergoing elective ovariohysterectomy, provided that dogs are screened for potential bleeding problems before surgery and monitored closely after surgery. 相似文献
974.
Pelsue DH Monnet E Gaynor JS Powers BE Halling K Parker D Golden A 《Journal of the American Animal Hospital Association》2002,38(6):569-576
Twenty normal, large-breed dogs underwent median sternotomy. Median sternotomies were closed with 20-gauge orthopedic wire in 10 dogs and no. 2 polybutester in 10 dogs. Closure with suture was faster than with wire (6.7 +/- 1.8 minutes versus 9.1 +/- 1.9 minutes, respectively). Significant differences were not observed in degree of postoperative pain or wound complication rates. Sternotomies closed with wire showed a trend to be more stable and had significantly less displacement on radiographic evaluation at 28 days. All sterna closed with wire examined histopathologically showed evidence of chondral or osteochondral bridging, while sterna closed with suture only showed fibrous union. 相似文献
975.
Skelly BJ Franklin RJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(2):133-141
Lysosomal storage diseases are rare, inherited disorders caused by the deficiency of 1 or more enzymes within the lysosomes of cells or by the deficiency of an activating protein or cofactor necessary for enzyme activity. The enzyme deficiency leads to a catabolic blockade and subsequent accumulation of storage material, and this in turn leads, albeit indirectly, to a wide array of clinical signs. Many features of storage diseases make them difficult to recognize and diagnose. In this review, we summarize the clinical features of these diseases and outline the steps required to confirm a diagnosis. 相似文献
976.
Analysis of heat shock protein 60 encoding genes of mycoplasmas and investigations concerning their role in immunity and infection 总被引:4,自引:0,他引:4
Only little is known about the heat shock proteins (Hsp) and Hsp-encoding genes of mycoplasmas. The aim of this study was to identify and sequence the hsp60 gene of Mycoplasma agalactiae, Mycoplasma arthritidis, Mycoplasma bovis, and Mycoplasma hyopneumoniae, and to investigate the immune response to Hsp60.Fragments of the hsp60 genes of M. agalactiae, M. arthritidis, M. bovis and M. hyopneumoniae representing almost the entire coding region were amplified by PCR. Two fragments of a hsp60 gene were cloned in Escherichia coli and the antibody response of pigs infected with M. hyopneumoniae against the recombinant Hsp60 fusion proteins was analysed. Within the mycoplasmas, the hsp60 genes showed sequence identities of nearly 100%, with the exception of the hsp60 gene of Mycoplasma genitalium, which was determined to be only 76.5-77.7% identical. Identities to Clostridium perfringens, Bacillus subtilis and E. coli were determined between approximately 50 and 60%. The predicted amino acid sequences of Hsp60 showed an identity of 90 to nearly 100% among mycoplasmas and 50-60% to the other bacteria indicated above. Two Hsp60 derived glutathione-S-transferase fusion proteins containing mycoplasma peptides of 28 and 35kDa were isolated. M. hyopneumoniae-ELISA positive porcine convalescent sera reacted strongly with the recombinant Hsp60 fusion proteins in Western immunoblotting indicating for the first time that mycoplasmal Hsp60 is immunogenic in natural infection. 相似文献
977.
978.
Effect on hematopoietic tissue of experimental infection of calves with noncytopathic type 2 bovine viral diarrhea virus 总被引:3,自引:0,他引:3 下载免费PDF全文
R. Darren Wood S. Denise Goens P. Suzanne Carman Dirk Deregt Barbara Jefferson Robert M. Jacobs 《Canadian journal of veterinary research》2004,68(1):42-48
To investigate the hematologic abnormalities observed with noncytopathic type 2 bovine viral diarrhea virus (ncpBVDV-2), calves 6 to 8 mo old were inoculated with an isolate of either high virulence (HV24515) or low virulence (LV11Q); control animals received the same volume of uninfected cell-culture supernatant. Peripheral blood neutrophil, lymphocyte, and platelet counts decreased in all the virus-inoculated calves but were significantly lower and remained decreased longer in the calves given HV24515. For each isolate, a decrease in the number of mature myeloid cells in the bone marrow coincided with the development of neutropenia, but the depletion persisted significantly longer (4 to 6 d) in the calves given HV24515. In the bone marrow of calves given LV11Q, the number of proliferating myeloid cells increased in proportion to the decrease in the number of mature myeloid cells. In the calves inoculated with HV24515, BVDV antigen was observed in bone marrow cells when the peripheral blood counts were lowest. Megakaryocytes were the predominant cell type exhibiting positive BVDV staining; myeloid cells rarely stained positively. Viral antigen was not observed in the bone marrow of calves given LV11Q. These experiments demonstrated that ncpBVDV-2 isolates of both high and low virulence caused decreased leukocyte and platelet counts, but only the high-virulence HV24515 isolate caused a delay in the production of myeloid proliferating cells. The delay may contribute to the ability of certain ncpBVDV-2 isolates to induce severe disease. 相似文献
979.
Use of a commercial methylcellulose medium with and without recombinant bovine granulocyte colony-stimulating factor for culturing bovine bone marrow cells 下载免费PDF全文
Sonya L. Keller R. Darren Wood Barbara J. Jefferson Robert M. Jacobs 《Canadian journal of veterinary research》2004,68(2):157-159
A commercial methylcellulose culture medium, with and without the addition of recombinant bovine granulocyte colony-stimulating factor (rbG-CSF), was utilized for culturing bovine bone marrow cells in a colony-forming unit assay. Bone marrow mononuclear cells were isolated and cultured in a commercial methylcellulose-based medium containing several recombinant human cytokines. Cultures were prepared with and without 100 ng/mL of rbG-CSF. The size and mean number of colonies per plate from culture days 3 to 9 were compared. We concluded that bovine bone marrow colony growth was supported by this culture medium. The addition of rbG-CSF yielded larger and more numerous colonies. There were significantly more colonies on day 3 (P < 0.001), day 4 (P < 0.001), and day 5 (P = 0.03) with rbG-CSF. Both culture media had the highest colony counts on day 5. 相似文献
980.