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991.
Background: Concurrent chemo- and radiotherapy improves outcome of certain human neoplasms but with increased signs of toxicity. Reports on adverse effects of concurrent chemo- and radiotherapy in the veterinary literature are scant.
Objective: To report adverse hematologic and gastrointestinal effects of combined carboplatin and radiation therapy in dogs.
Animals: Client-owned dogs with spontaneously occurring neoplasia.
Methods: Retrospective case study. Medical records of 65 dogs were reviewed. Criteria for inclusion were administration of radiation according to 1 of 3 fractionation schemes (19 × 3, 16 × 3, or 12 × 4 Gy) and administration of at least 1 concurrent carboplatin treatment at a dosage of 200–300 mg/m2. Dog and treatment-related variables were analyzed for association with signs of intoxication.
Results: Median carboplatin dosage was 200 mg/m2 (range, 200–250 mg/m2). Twelve of 58 dogs (21%) developed grade 3 or 4 neutropenia. Eleven of 56 dogs (20%) developed grade 3 or 4 thrombocytopenia. Six of 62 dogs (10%) developed grade 3, 4, or 5 gastrointestinal toxicosis. Analysis of association of dog and treatment-related variables with signs of intoxication was hampered by the small numbers of dogs in individual groups, and no statistically significant associations were found.
Conclusions and Clinical Importance: Combined modality therapy resulted in myelosuppression and gastrointestinal toxicosis. Future studies are needed to determine whether the potential benefit of combined modality therapy outweighs the risk of decreasing chemotherapy and radiation treatment intensity.  相似文献   
992.
993.
From May 2007 to May 2008 we have examined by otoscopy a total number of 214 cats, aged between 0 and 6 months, brought in for their first veterinary examination to a private veterinary clinic. All cats were of urban origin. In all positive cats we performed a washing of the ear using warm paraffin oil in order to determine intensity of infection. Statistical analysis was performed using the Chi-square test. A total number of 30 cats were found to be infected with Otodectes cynotis (prevalence 14.02%). Prevalence of infection was significantly (p < 0.05) higher in cats aged between 3 and 6 months (17.58%) than in cats aged below 3 months (11.38). Intensity of infection ranged between 7 and 85 (mean intensity 35.60) mites per infected cat. The same age group of cats between 3 and 6 months had significantly (p < 0.05) higher mean intensity (47.19) compared to cats aged under 3 months (22.36). No statistical significance was found between males and females for neither prevalence nor intensity. Differences and similarities with other studies are discussed.  相似文献   
994.
Advances in immunoparasitology   总被引:1,自引:0,他引:1  
A selective review of the advances in immunoparasitology is presented. It is selective simply because it is not feasible to embrace the whole field of parasitology within the compass of a single review paper, for if it were attempted, it would suffer undue abbreviation. Emphasis is placed on the advances in helminthology and especially the gastro-intestinal parasites of ruminants, an obvious selection because of the interests of the author. Reviews are always somewhat retrospective in outlook; to write a review at the present time is especially foolhardy since developments in biology are such that totally new concepts can arise almost overnight, as it were. This is a particularly healthy state, and the discipline of parasitology is caught up in the application and interpretation of molecular biological considerations. "Parasitism" is a field of increasing importance and challenge.  相似文献   
995.
996.
Fifty-four crossbred steers (275 kg) were assigned randomly to one of three isoenergetic but not isonitrogenous ruminal escape protein (EP) supplements: high ruminal escape protein (HEP), low ruminal escape protein (LEP), or corn. The supplements contained corn, distillers' dried grains with solubles (DDGS), and fish meal. Supplements were fed at approximately 1.5 kg/d; the HEP and LEP supplements provided .25 and .12 kg more EP per day than corn, respectively. These supplements also supplied .20 and .10 kg more CP per day than corn. Fish meal and DDGS provided 66.7 and 33.3% of the supplemental EP, respectively. One-half of the steers in each supplement treatment were implanted once with 36 mg of zeranol. Steers grazed wheat (Triticum aestivum L.)-annual ryegrass (Lolium multiflorum Lam.) pastures for 73 d (March 1 to May 12). Daily gains (kg/d) increased linearly (P less than .07) as EP increased (HEP, 1.61; LEP, 1.54; corn, 1.47); responses were apparent only during the later periods as forage quality declined. Zeranol implants increased (P less than .02) ADG (kg/d) by 9.7% (1.58 vs 1.44). After grazing, all cattle were fed a finishing ration for 76 d. Pre-feedlot EP level produced a negative linear (P less than .04) response on feedlot ADG (kg/d) (HEP, 1.44; LEP, 1.50; corn, 1.59). Zeranol implantation during the grazing phase did not affect (P greater than .2) performance during the feedlot phase or carcass characteristics other than increased ribeye area (P less than .08). Compensatory feedlot performance negated all weight gain advantages elicited by EP supplementation during the grazing period.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
997.
Nine monoclonal antibodies which reacted with equine immunoglobulin (Ig)M and not other equine Ig and serum proteins were prepared. Cells producing antibodies (C 1.9) which precipitated with IgM and bound to staphylococcal protein A were triple-cloned (C 1.9/3.2) and the antibodies further characterized. Monoclonal antibody C 1.9/3.2 reacted with an IgM determinant present on serum IgM from horses of several breeds. Studies with 125I-labeled IgM revealed the presence of this determinant on all IgM molecules. The monoclonal antibody enabled quantitation of IgM in presuckling foal and adult horse sera, using rocket electrophoresis. This procedure was used because presumably it gives a positive precipitation reaction over a wide range of antigen-antibody ratios. The C 1.9/3.2 monoclonal antibody recognized an exposed mu-chain determinant on live B lymphocytes, as determined by immunofluorescence. Also, IgM-containing cells could be identified in acetone-fixed frozen sections of lymphoid tissue. Sera from several other species carry the determinant identified by C 1.9/3.2, suggesting that the reagent may be useful for IgM studies in other species.  相似文献   
998.
A rapid, simple fluorometric method is described for measuring antibody to Pasteurella haemolytica in sera of cattle. Various antigen preparations were compared for the test including live, formalin-killed and phenol-killed P. haemolytica. A preparation composed of formalin-killed organisms from a 22 hour culture gave consistent results and was used in the studies. The test was reproduciable with percent coefficients of variation for fluorescent signal unit values on ten or more replicate samples ranging from 5.7 to 28.0. Sera from calves vaccinated by aerosol exposure to live P. haemolytica had up to a five-fold increase in antibody titer as measured by the flurometric method test during a 21 day period. Fluorometric method titers were comparable to those obtained by the indirect bacterial agglutination test. There was no seroconversion to P. haemolytica in calves vaccinated by aerosol exposure of P. multocida. The major advantages of the fluorometric method test over conventional methods are that the assay does not require serial dilutions of serum samples and thus limits time and effort to determine antibody titers.  相似文献   
999.
Sixteen grey duikers were culled on the farm Riekert 's Laager in the central Transvaal at irregular intervals from May 1979-March 1981. One trematode species, 3 cestode species and 16 nematode species were recovered from these animals. Of these the following are new helminth records for this antelope: Cooperia hungi , Cooperia neitzi , Cooperia pectinata , Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus falculatus , Trichostrongylus instabilis , Impalaia tuberculata , Nematodirus sp. and Paramphistomum sp. In addition, 6 species of ixodid ticks were collected. These, in order of abundance, were Amblyomma hebraeum (55,9%), Rhipicephalus appendiculatus (36,6%), Rhipicephalus evertsi evertsi (5,1%), Boophilus decoloratus (2,3%), Boophilus microplus (0,05%) and Haemaphysalis sp. (0,05%). Only 60 (2,8%) of the 2 118 ticks that were collected were adults. Of the 3 species of lice that were recovered, Linognathus zumpti zumpti was most abundant (58,9%), but, out of a total of 1 498 collected, 1 496 occurred on 1 animal only. Linognathus breviceps constituted 29,5% and Damalinia lerouxi 11,6% of the total. A total of 277 specimens of the hippoboscid fly Lipoptena paradoxa were collected from 12 of the 16 animals examined. Trends in the seasonal fluctuation of Haemonchus, Trichostrongylus, Impalaia , Lipoptena and the immature stages of Amblyomma and R. appendiculatus are graphically illustrated.  相似文献   
1000.
Anterior pituitary gland contents of LH and LHß- and α-subunit mRNAs, and circulating concentrations of LH and testosterone, were determined in bulls treated with the LH-releasing hormone (LHRH) agonist deslorelin. Brahman (Bos indicus) bulls (14-month-old) were allocated to two groups and received the following: Control (n = 5), no treatment; Deslorelin (n = 4), four deslorelin implants (approximately 200 μg total deslorelin/day) for 36 d. Plasma concentrations of LH were higher in bulls treated with deslorelin on Day 1, had returned to typical levels by Day 8, and did not differ for control bulls and bulls treated with deslorelin from Day 8 to Day 29. Pituitary content of LH on Day 36 was reduced (P < 0.001) in bulls treated with deslorelin (33 ± 4 ng/mg) compared with control bulls (553 ± 142 ng/mg). Relative pituitary content of LHß-subunit mRNA was also reduced on Day 36 in bulls treated with deslorelin (Control, 0.65 ± 0.10; Deslorelin, 0.22 ± 0.04; P = 0.003). However, α-subunit mRNA relative content did not differ (Control, 0.73 ± 0.15; Deslorelin, 1.06 ± 0.12; P > 0.05). Plasma concentrations of testosterone were increased over the period of the experiment in the bulls treated with deslorelin compared with control bulls. This is the first demonstration of reduced pituitary content of LHß-subunit mRNA and LH, and unaltered content of α-subunit mRNA, in bulls treated with LHRH agonist. This was associated with apparently typical plasma concentrations of LH and elevated plasma testosterone. The anterior pituitary in bulls treated with LHRH agonist, therefore, undergoes classical desensitization and downregulation, but plasma LH and testosterone are not suppressed.  相似文献   
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