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排序方式: 共有253条查询结果,搜索用时 31 毫秒
41.
Brisson BA Moffatt SL Swayne SL Parent JM 《Journal of the American Veterinary Medical Association》2004,224(11):1808-1814
OBJECTIVES: To evaluate a population of chondrodystrophic dogs treated for Hansen type 1 intervertebral disk (IVD) disease by surgical decompression with or without prophylactic fenestration and determine the rate and location of surgically confirmed recurrence of intervertebral disk extrusion. ANIMALS: 265 dogs. STUDY DESIGN: Retrospective study. PROCEDURES: Medical records of dogs that underwent spinal decompression between 1995 and 1999 were reviewed. RESULTS: 3 (4.9%) dogs were euthanatized or died prior to discharge. Fenestration was performed in 252 dogs, including 37 (14.7%) at the site of decompression only, 48 (19%) at 3 to 4 disk spaces, and 167 (66%) at 5 to 7 disk spaces. There were 12 instances of recurrent disk extrusion confirmed by removal of disk at a second surgery 3.5 to 33 months after the first surgery. Recurrence was always at a new disk space, and rates did not significantly differ between dogs that underwent single or multiple fenestrations. Two recurrences were at a previously fenestrated disk space. Seven recurrences were at a site immediately adjacent to a fenestrated disk space, and 5 recurrences were at L4-5. CONCLUSIONS AND CLINICAL RELEVANCE: Prophylactic fenestration is generally successful in preventing future disk extrusions at fenestrated disk spaces. Prospective evaluation is still required to determine whether fenestration decreases the overall rate of recurrence. Prophylactic fenestration could promote disk extrusion at adjacent, nonfenestrated disk spaces. This could have a substantial clinical impact if recurrence develops at L4-5. 相似文献
42.
Hewitt SA Brisson BA Sinclair MD Foster RA Swayne SL 《Journal of the American Veterinary Medical Association》2004,225(1):65-71
OBJECTIVE: To evaluate feasibility of performing laparoscopic-assisted placement of a jejunostomy feeding tube (J-tube) and compare complications associated with placement, short-term feedings, and medium-term healing with surgically placed tubes in dogs. DESIGN: Prospective study. ANIMALS: 15 healthy mixed-breed dogs. PROCEDURES: Dogs were randomly allocated to undergo open surgical or laparoscopic-assisted J-tube placement. Required nutrients were administered by a combination of enteric and oral feeding while monitoring for complications. Radiographic contrast studies documented tube direction and location, altered motility, or evidence of stricture. RESULTS: Jejunostomy tubes were successfully placed in the correct location and direction in all dogs. In the laparoscopic group, the ileum was initially selected in 2 dogs, 2 dogs developed moderate hemorrhage at a portal site, and 2 J-tubes kinked during placement but were successfully readjusted postoperatively. All dogs tolerated postoperative feedings. All dogs developed minor ostomy site inflammation, and 1 dog developed bile-induced dermatitis at the ostomy site. Despite mild, transient neutrophilia, no significant difference was noted in WBC counts between groups. No dog had altered gastric motility or evidence of stricture, although the jejunopexy site remained identifiable in several dogs at 30 days. CONCLUSIONS AND CLINICAL RELEVANCE: Requirements for successful J-tube placement were met by use of a laparoscopic-assisted technique, and postoperative complications were mild and comparable to those seen with surgical placement. Laparoscopic-assisted J-tube placement compares favorably to surgical placement in healthy dogs and should be considered as an option for dogs requiring enterostomy feeding but not requiring a celiotomy for other reasons. 相似文献
43.
El-Warrak AO Olmstead M Apelt D Deiss F Noetzli H Zlinsky K Hilbe M Bertschar-Wolfsberger R Johnson AL Auer J von Rechenberg B 《Veterinary surgery : VS》2004,33(5):495-504
OBJECTIVE: To create a model in sheep for investigation of early changes related to the formation of an interface membrane in hip prosthesis. STUDY DESIGN: Experimental study. ANIMALS: Twenty-four female adult Swiss Alpine sheep. METHODS: Sheep were divided into 2 groups of 12 for unilateral cemented total hip arthroplasty. In Group I, the prosthesis was fixed with retrograde cement gun injection to achieve a complete cement mantle, whereas in Group II a primary cement mantle defect was produced. Groups I and II were further divided into 2 sub-groups with study end points of 2 and 8.5 months after surgery. Radiographs were evaluated postoperatively and at euthanasia for migration of the femoral component and bone resorption. Histologic sections were evaluated semiquantitatively for changes in cell types and numbers, and bone reactions; and quantitatively for size of interface membrane and new bone formation. RESULTS: Radiographically, there tended to be an increase in bone resorption and periosteal bone formation throughout the femoral shaft in Group II compared with Group I, but this was only statistically significant at the region of the femoral neck (R5) at both time periods (P<.05). Semiquantitative histologic evaluation revealed significant increases (P<.05) in cellularity, numbers of fibroblasts, giant cells, macrophages, and mononuclear cells, in Group II primarily at 2 months after surgery. This was also true for interface membrane formation and bone remodeling. Quantitative data showed an increased in the size of the interface membrane and area of bone formation at 8.5 months in Group II. CONCLUSIONS: The cement defect model offered controlled and repeatable production of an interface membrane. The results suggest that a primary cement mantle defect could be a possible trigger for implant instability, eliciting a cascade of biomechanical and molecular events in bone tissue leading to aseptic loosening. CLINICAL RELEVANCE: The results show the effect of defects in the cement mantle in promoting interface membrane formation. Long-term and biochemical studies are required to evaluate the relevance of this interface membrane formation. 相似文献
44.
Bibring JP Langevin Y Mustard JF Poulet F Arvidson R Gendrin A Gondet B Mangold N Pinet P Forget F Berthé M Bibring JP Gendrin A Gomez C Gondet B Jouglet D Poulet F Soufflot A Vincendon M Combes M Drossart P Encrenaz T Fouchet T Merchiorri R Belluci G Altieri F Formisano V Capaccioni F Cerroni P Coradini A Fonti S Korablev O Kottsov V Ignatiev N Moroz V Titov D Zasova L Loiseau D Mangold N Pinet P Douté S Schmitt B Sotin C Hauber E Hoffmann H Jaumann R Keller U Arvidson R Mustard JF Duxbury T 《Science (New York, N.Y.)》2006,312(5772):400-404
Global mineralogical mapping of Mars by the Observatoire pour la Mineralogie, l'Eau, les Glaces et l'Activité (OMEGA) instrument on the European Space Agency's Mars Express spacecraft provides new information on Mars' geological and climatic history. Phyllosilicates formed by aqueous alteration very early in the planet's history (the "phyllocian" era) are found in the oldest terrains; sulfates were formed in a second era (the "theiikian" era) in an acidic environment. Beginning about 3.5 billion years ago, the last era (the "siderikian") is dominated by the formation of anhydrous ferric oxides in a slow superficial weathering, without liquid water playing a major role across the planet. 相似文献
45.
46.
Brisson BA Reggeti F Bienzle D 《Journal of the American Veterinary Medical Association》2006,229(6):980-983
CASE DESCRIPTION: A 10-year-old Golden Retriever evaluated because of recurrent pericardial and pleural effusion underwent thoracoscopy with biopsy of the pleura and mediastinum. CLINICAL FINDINGS: Before thoracoscopy, 5 L of serosanguinous fluid was removed from the pleural cavity via thoracocentesis. During thoracoscopic exploration, it was observed that the parietal pleura and mediastinum were covered by miliary white to tan nodules 1 to 3 mm in diameter. Biopsy specimens were obtained, and partial pericardiectomy was performed. Portal sites were closed routinely. Cytologic evaluation of the pleural fluid revealed high protein concentration and cellularity, with cellular changes consistent with an exfoliating carcinoma. Results of bacterial culture were negative. TREATMENT AND OUTCOME: Carboplatin was administered via intracavitary instillation, and prednisone was administered orally. Twenty-one days later, 1 firm, irregularly shaped 6.5 x 3-cm mass and 4 smaller masses were detected in the area of the left thoracic wall where the cannula had been inserted during thoracoscopy. Histologic analysis of tissue from the masses collected at necropsy confirmed that they were malignant tumors with similar appearance to the pleural mesothelioma and immunohistochemical staining properties identical to those of the primary tumor. CLINICAL RELEVANCE: Although thoracoscopy is associated with less postoperative pain, shorter hospitalization times, and faster patient recovery than sternotomy procedures, complications are also possible with minimally invasive endoscopic surgery. Portal site metastasis can develop from contamination of portal sites with cells on instruments or cannulas or via leakage of effusion fluid. Although rare, this potential complication should be discussed with owners prior to performing the procedure. 相似文献
47.
48.
Brigitte Engelking Heiner Flessa Rainer Georg Joergensen 《Soil biology & biochemistry》2008,40(1):97-105
A 67-day incubation experiment was carried out with a soil initially devoid of any organic matter due to heating, which was amended with sugarcane sucrose (C4-sucrose with a δ13C value of ?10.5‰), inorganic N and an inoculum for recolonisation and subsequently at day 33 with C3-cellulose (δ13C value of ?23.4‰). In this soil, all organic matter is in the microbial biomass or in freshly formed residues, which makes it possible to analyse more clearly the role of microbial residues for decomposition of N-poor substrates. The average δ13C value over the whole incubation period was ?10.7‰ in soil total C in the treatments without C3-cellulose addition. In the CO2 evolved, the δ13C values decreased from ?13.4‰ to ?15.4‰ during incubation. In the microbial biomass, the δ13C values increased from ?11.5‰ to ?10.1‰ at days 33 and 38. At day 67, 36% of the C4-sucrose was left in the treatment without a second amendment. The addition of C3-cellulose resulted in a further 7% decrease, but 4% of the C3-cellulose was lost during the second incubation period. Total microbial biomass C declined from 200 μg g?1 soil at day 5 to 70 μg g?1 soil at day 67. Fungal ergosterol increased to 1.5 μg g?1 soil at day 12 and declined more or less linearly to 0.4 μg g?1 soil at day 67. Bacterial muramic acid declined from a maximum of 35 μg g?1 soil at day 5 to a constant level of around 16 μg g?1 soil. Glucosamine showed a peak value at day 12. Galactosamine remained constant throughout the incubation. The fungal C/bacterial C ratio increased more or less linearly from 0.38 at day 5 to 1.1 at day 67 indicating a shift in the microbial community from bacteria to fungi during the incubation. The addition of C3-cellulose led to a small increase in C3-derived microbial biomass C, but to a strong increase in C4-derived microbial biomass C. At days 45 and 67, the addition of N-free C3-cellulose significantly decreased the C/N ratio of the microbial residues, suggesting that this fraction did not serve as an N-source, but as an energy source. 相似文献
49.
Muluneh Tamiru Heiko C. Becker Brigitte L. Maass 《Genetic Resources and Crop Evolution》2008,55(1):115-131
Yam (Dioscorea spp.) is widely grown in many parts of Ethiopia and plays a vital role in local subsistence. Nevertheless, its diversity
has not been studied in detail. A survey covering 339 farm households and eight districts was conducted in the major yam growing
regions of Southern Ethiopia to investigate the diversity and distribution of yam landraces using structured and semi-structured
questionnaires. A total of 37 named landraces were recorded, with a range from one to six (mean 2.9) on individual farms.
Farmers’ decisions regarding the number and type of landraces maintained was influenced by tolerance of the landraces to drought,
their maturity time and market demand. Most landraces had limited abundance and distribution, and only a few dominant landraces
were widely grown. There was also variation amongst districts with respect to diversity, distribution and abundance of the
landraces found. In the majority of the localities surveyed, farmers reported a decreasing trend in the number of landraces
maintained on individual farms and in the overall yam production. Besides, in those limited areas where yam production is
expanding, farmers are increasingly relying on a few selected landraces that mature early. Findings of this study suggest
that local farmers in Wolayita and Gamo-Gofa zones maintain considerable yam diversity that remains to be further explored
for sustainable utilization and conservation of the available genetic resources. 相似文献
50.
Arends B Spee B Hoffmann G Jansen GE Slump E Auriemma E Ijzer J Hemrika W Romijn RA van der Heijden-Liefkens KH Sondermeijer PJ van den Ingh TS Penning LC Rothuizen J 《Veterinary journal (London, England : 1997)》2008,178(1):70-77
Hepatocyte growth factor (HGF) is crucial for the development and regeneration of the liver and offers a possible new therapeutic strategy for the treatment of canine liver disease. In this study, the in vitro and in vivo bioactivity of recombinant canine HGF (rcHGF) produced with a baculoviral expression system in insect cells was measured. In vitro rcHGF induced mitogenesis, motogenesis, and phosphorylated the HGF receptor c-MET and its downstream mediators PKB and ERK1/2 in two canine epithelial cell lines. After a partial hepatectomy (phx) in dogs, rcHGF increased phosphorylation of c-MET, PKB and ERK1/2. A moderate increase was seen with the cell cycle protein PCNA in rcHGF treated livers, but no HGF-induced increase in liver weight was seen 7 days after phx. Furthermore, rcHGF treated livers showed lower levels of the key mediator of apoptosis, caspase-3, at 7days after phx. It is concluded that rcHGF is a biologically active protein in vitro and in vivo and the baculoviral expression system supplies sufficient amounts of rcHGF for future clinical studies in dogs. 相似文献