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11.
Sorenmo K Samluk M Clifford C Baez J Barrett JS Poppenga R Overley B Skorupski K Oberthaler K Van Winkle T Seiler G Shofer F 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(6):1347-1354
BACKGROUND: Canine splenic hemangiosarcoma (HSA) is a fatal malignancy, and most affected dogs die within a few months of diagnosis. Most dogs present with signs from tumor rupture, resulting in hemoabdomen and intra-abdominal dissemination. The abdomen is also the main site of disease recurrence. HYPOTHESIS: Intraperitoneal (IP) administration of doxorubicin will delay or prevent intra-abdominal tumor recurrence and prolong survival in dogs with HSA. ANIMALS: Fourteen dogs with splenic HSA. METHODS: A prospective, unmasked, uncontrolled clinical trial. After staging of disease status and splenectomy, pegylated liposomal encapsulated doxorubicin was administered intraperitoneally (1 mg/kg body weight) every 3 weeks for 4 cycles. All dogs were monitored for recurrence of HSA. Samples of plasma and abdominal fluid were collected for measurement of doxorubicin concentration and pharmacokinetic analysis. Nonlinear mixed-effect modeling was used to describe the pharmacokinetics of liposomal doxorubicin administered IP. RESULTS: All 14 dogs died, 12 because of HSA and 2 from other causes. Postmortem examination was performed on 12 dogs. All 12 dogs died because of HSA-related causes and had hepatic metastases and hemoabdomen. The IP-treated dogs had fewer serosal, mesenteric, and omental metastases than historical controls treated with systemic doxorubicin. Results of the postmortem examination and pharmacokinetic analysis confirmed that IP delivery of doxorubicin resulted in an effective drug concentration with a clearance comparable with that after i.v. delivery. CONCLUSIONS AND CLINICAL IMPORTANCE: IP pegylated liposomal encapsulated doxorubicin administration did not prevent intraabdominal recurrence of HSA in dogs. 相似文献
12.
Britt T Clifford C Barger A Moroff S Drobatz K Thacher C Davis G 《The Journal of small animal practice》2007,48(3):145-150
OBJECTIVES: To determine the ability to obtain diagnostic cytology samples from appendicular bone lesions using ultrasound-guided needle aspirations. Secondary objectives were to compare cytological evaluations with histopathological results and to determine the utility of staining malignant mesenchymal cells for the presence of alkaline phosphatase. METHODS: Aspirations from 36 aggressive appendicular bone lesions with histological diagnoses were included in the study. Ultrasound was used to guide the needle to the medullary cavity or the adjacent soft tissue mass. The smears stained with Wright-Giemsa and nitroblue tetrazolium chloride/5-bromo-4-chloro-3-indoyl phosphate toluidine salt (NBT/BCIP) were examined. RESULTS: A diagnostic sample was obtained in 32 of the 36 cases. Of the 32 diagnostic samples, cytology indicated sarcoma, with a sensitivity of 97 per cent (confidence interval: 83 to 100 per cent) and a specificity of 100 per cent (confidence interval: 16 to 100 per cent). When a diagnosis of sarcoma was made on cytology, alkaline phosphatase staining indicated osteosarcoma, with a sensitivity of 100 per cent (confidence interval: 87 to 100 per cent). CLINICAL SIGNIFICANCE: The results of this study indicate that ultrasound-guided needle aspiration of aggressive bone lesions is a viable technique for identifying malignant mesenchymal cells and for diagnosing sarcomas. It is cost-effective and minimally invasive. Furthermore, identifying alkaline-phosphatase-negative malignant mesenchymal cells from a bone aspiration may rule out osteosarcoma, whereas alkaline-phosphatase-positive malignant mesenchymal cells are suggestive of osteosarcoma. 相似文献
13.
The products from the methylene blue sensitised photo-oxidation of 2-dimethylamino-5,6-dimethylpyrimidin-4-ol (I) in deuterochloroform/deuteroacetone have been investigated. A zwitterion and a hydroperoxide are formed initially, with the zwitterion predominating. The zwitterion compound degrades or reacts in the solid state on silica gel to give further products. 相似文献
14.
The Rose Bengal sensitised photo-oxidation of bioresmethrin (I), 2-benzylfuran-4-ylmethyl acetate (II), and 2-benzylfuran-4-ylmethanol (III) has been studied in methanol and methanol + water (1 + 1 by volume) solutions by monitoring the rate or oxygen removal from the system. The results indicate that the compounds studied are oxidised via reaction with singlet oxygen. Values for the rate constants for reaction of singlet oxygen with compounds I-III have been determined over the temperature range 293–308 K, and the energy of activation and entropy of activation for the reactions have been determined. The data have been interpreted in terms of the site of attack of singlet oxygen on the compounds. 相似文献
15.
Studies on sodium bentonite in ruminant diets containing urea 总被引:1,自引:0,他引:1
16.
Swinebroad EL Dabareiner RM Swor TM Carter GK Watkins JP Walker M Schmitz DG Honnas CM 《Journal of the American Veterinary Medical Association》2003,223(4):486-491
OBJECTIVE: To determine clinical, radiographic, and scintigraphic abnormalities in and treatment and outcome of horses with trauma-induced osteomyelitis of the proximal aspect of the radius. DESIGN: Retrospective study. ANIMALS: 5 horses. PROCEDURE: Data collected from the medical records included signalment; history; horse use; degree of lameness; radiographic, ultrasonographic, and scintigraphic findings; treatment; and outcome. RESULTS: Duration of lameness prior to referral ranged from 14 to 60 days. Mean severity of lameness was grade 3 of 5, and all horses had a single limb affected. All horses had signs of pain during elbow joint manipulation and digital palpation over the lateral aspect of the proximal end of the radius. Radiographic lesions consisted of periosteal proliferation, osteolysis, and subchondral bone lysis. Scintigraphy in 3 horses revealed intense pharmaceutical uptake diffusely involving the proximal end of the radius. Two horses had sepsis of the elbow joint. All horses were treated with antimicrobials long-term; 1 horse was also treated by local perfusion of the radial medullary cavity through an indwelling cannulated screw. At follow-up, all horses had returned to their previous function. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that osteomyelitis of the proximal end of the radius can result from a traumatic injury to the antebrachium. Because lesions may be an extension of septic arthritis, a thorough examination of the wound area and elbow joint is recommended. Prolonged systemic antimicrobial treatment can result in a successful outcome. 相似文献
17.
Hawkins EC Basseches J Berry CR Stebbins ME Ferris KK 《Journal of the American Veterinary Medical Association》2003,223(11):1628-1635
OBJECTIVE: To determine demographic, clinical, and radiographic features of bronchiectasis in dogs. DESIGN: Retrospective study. ANIMALS: 289 dogs identified through the Veterinary Medical Database (VMDB) and 27 dogs examined at the North Carolina State University Veterinary Teaching Hospital. PROCEDURE: Demographic characteristics of dogs identified through the VMDB were compared with characteristics of the entire population of dogs entered in the VMDB. Medical records of dogs examined at the teaching hospital were reviewed; the diagnosis was confirmed through review of thoracic radiographs. RESULTS: Analysis of data from the VMDB indicated that American Cocker Spaniels, West Highland White Terriers, Miniature Poodles, Siberian Huskies, English Springer Spaniels, and dogs > 10 years old had an increased risk of bronchiectasis. Among dogs examined at the teaching hospital, coughing was the most common clinical sign. There was evidence for excessive airway mucus but not hemorrhage. A variety of bacterial organisms were isolated from tracheal wash and bronchoalveolar lavage samples. On thoracic radiographs, cylindrical bronchiectasis, generalized disease, and right cranial lung lobe involvement were most common. Seven of 14 dogs for which follow-up radiographs were available did not have any progression of radiographic lesions. Median duration of clinical signs prior to diagnosis of bronchiectasis was 9 months (range, 1 day to 10 years). Median survival time was 16 months (range, 2 days to 72 months). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that despite substantial clinical abnormalities, dogs with bronchiectasis may survive for years. Certain purebred dogs and older dogs may have an increased risk of developing bronchiectasis. 相似文献
18.
Samii VF Les Clifford M Schulz KS Keyak JH Stover SM 《American journal of veterinary research》2002,63(8):1159-1166
OBJECTIVE: To evaluate subchondral bone density patterns in elbow joints of clinically normal dogs by use of computed tomographic (CT) osteoabsorptiometry. SAMPLE POPULATION: 20 cadaver forelimbs from 10 clinically normal dogs. PROCEDURE: Each elbow joint was imaged in parasagittal and transverse planes of 1.5-mm thickness. Slice data were converted to dipotassium phosphate equivalent density (PPED) values. Sagittal, parasagittal, and transverse medial coronoid process topographic maps were constructed. Defined zones were created for each of the 3 CT planes, and confluence and peak PPED values were determined. RESULTS: The lowest PPED value was 340 mg/ml (articular and subchondral confluence), and the highest was 1780 mg/ml (peak subchondral density). Detectable effects of joint laterality were not found in the confluence or peak PPED measurements or in the peak-to-confluence PPED ratio for all 3 CT planes. Significant differences were found among zones in all 3 planes for confluence and peak PPED measurements and between sagittal and transverse planes for peak-to-confluence PPED ratios. Subjectively, the pattern of density distribution among dogs was fairly consistent for the sagittal and parasagittal slices. Three specific patterns of density distribution were apparent on the transverse topographic maps of the medial coronoid process that corresponded to conformational differences. CONCLUSIONS AND CLINICAL RELEVANCE: The use of CT osteoabsorptiometry provides a repeatable technique that can be used to noninvasively examine bone density and the effects of stress acting on joints in vivo. Variability in density values for any of the CT planes was not identified among clinically normal dogs. 相似文献
19.
Effects of Body Condition and Protein Supplementation on LH Secretion and Luteal Function in Sheep 总被引:1,自引:0,他引:1
CA Meza-Herrera T Ross D Hallford D Hawkins A Gonzalez-Bulnes 《Reproduction in domestic animals》2007,42(5):461-465
In ruminants, nutrition is one of the exogenous inputs affecting reproductive function at different levels of the hypothalamic-hypophyseal-gonadal axis. However, the exact mechanisms or even the identification of the signalling metabolic compounds by which nutrition affects reproductive function still need further clarification. The role of static body condition (BC) and its interaction with a short-term protein supplementation (PL), on secretion of metabolic hormones [growth hormone (GH), insulin and insulin-like growth factor-1 (IGF-1)], as well as on secretion of LH and progesterone (P4) was evaluated in sheep. Twenty-four Rambouillet ewes divided into two groups, with lower (LBC) and higher body condition (HBC), were randomly assigned within BC to one of two PL levels: low (LPL, 24% of crude protein; 14 g/animal/day), and high (HPL, 44% of crude protein; 30 g/animal/day). The secretion of GH, insulin, IGF-1 and LH was evaluated on day 10 of the oestrous cycle; appearance and timing of oestrous behaviour were previously detected using rams. Progesterone secretion was evaluated on day 13 of the same cycle. No differences were found (p > 0.05) between PL groups on serum GH concentrations during the sampling period (overall mean of 4.0 +/- 0.3 ng/ml), but a trend for lower values in HBC sheep was found (3.6 +/- 0.4 vs 4.4 +/- 0.4 ng/ml, p = 0.06). A BC effect was observed (p < 0.05) on serum IGF-1 level, with higher values in HBC sheep (p < 0.05). Neither BC nor PL affected (p > 0.05) secretion of LH and the number of corpora lutea, nor serum P4 and insulin concentrations. Results indicate a predominance of the static component of nutrition on sheep metabolic hormone responses, GH and IGF-1, with no effect of short-term PL on secretion of pituitary and ovarian hormones as well as luteal number and activity. 相似文献
20.
Follicular Dynamics in Heifers during Pre-pubertal and Pubertal Period Kept under Two Levels of Dietary Energy Intake 总被引:1,自引:0,他引:1
MA Romano VH Barnabe JP Kastelic CA de Oliveira RM Romano 《Reproduction in domestic animals》2007,42(6):616-622
The objective of this study was to characterize follicular dynamics in pre-pubertal, pubertal and post-pubertal periods, as well as the effect of high-energy intake on follicular development and age at puberty in heifers. Thirty-one Nelore (Bos indicus) heifers, 6 months old, were randomly assigned to receive two different diets: one of low (GI) and other of high dietary energy intake (GII). Animals were evaluated in relation to body weight gain by being weighed every 21 days. Heifers were evaluated every other day by real-time linear ultrasonography to characterize ovarian structures development from weaning to post-pubertal period. Blood samples were collected to determine plasmatic concentrations of progesterone by RIA method. The ovulation was determined when progesterone concentrations were >1 ng/mL in three consecutive samples, and by ultrasound images of corpus luteum; and oestrous behaviour in some animals. Age at puberty differed among heifers of GII (17.00 +/- 0.46 months) compared with heifers of GI (19.87 +/- 0.47 months; p < or = 0.05). Maximum size of the dominant follicles at pre-pubertal period was greater in GII heifers than in GI (10.52 +/- 0.33 and 9.76 +/- 0.15 mm, respectively; p < or = 0.05). As heifers approached first ovulation time, size of dominant follicle increased (11.75 +/- 0.37 mm for GI and 12.52 +/- 0.91 mm for GII; p < or = 0.05). Body weight at puberty was not different in both groups (302.33 +/- 27.31 kg for GI and 326.19 +/- 27.78 kg for GII heifers; p > 0.05). We conclude that animals receiving high dietary energy intake attained the puberty earlier and the development of follicles were different than in low dietary energy intake. 相似文献