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1.
Latissimus dorsi and cutaneous trunci myocutaneous flaps of equal dimension and location were randomly elevated on opposite sides of the thorax in 10 dogs (group 1) and resutured to their respective bed. The procedure was repeated in four additional dogs (group 2); however, the short perforating branches of the thoracodorsal artery and vein were divided at the base of each cutaneous trunci myocutaneous flap, whereas the cutaneous pedicle and underlying cutaneous trunci muscle were divided in the latissimus dorsi myocutaneous flaps to determine subsequent skin survivability and the major source of circulation of each myocutaneous flap. There was little difference in the percentage of skin survival between the latissimus dorsi and cutaneous trunci myocutaneous flaps in group 1 dogs. Circulation to the "skin island" of group 2 latissimus dorsi myocutaneous flaps originated from intramuscular anastomotic connections between the major branch of the thoracodorsal artery entering the latissimus dorsi muscle and the proximal lateral intercostal arteries perforating the muscle. Ligation of the short perforating branches of the thoracodorsal artery resulted in partial skin necrosis in all group 2 cutaneous trunci myocutaneous flaps. Results from this study indicate that it is unnecessary to elevate the latissimus dorsi muscle for major skin flap elevation and survival. The thicker latissimus dorsi myocutaneous flap is more difficult to develop surgically and appears to have no clinical major advantage over the more mobile cutaneous trunci myocutaneous flap or the adjacent thoracodorsal axial pattern flap for closure of large skin defects within the radius of flap rotation.  相似文献   
2.
Experiments with tick-paralyzed dogs and woodchucks have shown impairment of stretch reflexes in addition to partial paralysis at the neuromuscular junction. Stretch reflexes disappear very early during paralysis, whereas nociceptive reflexes do not appear to be directly affected. The early incoordination and the ascending nature of the paralysis may be related to impairment of stretch reflex pathways.  相似文献   
3.
Intramedullary masses are a dilemma due to the limited access for a nonsurgical biopsy, thus, accurate imaging characterization is crucial. Magnetic resonance imaging findings of two confirmed canine thoracic intramedullary hemangiomas are described. A capillary hemangioma was of mixed intensity but predominantly T2‐hyperintense and mildly T1‐hyperintense to spinal cord with strong contrast enhancement. A cavernous hemangioma had a target‐like appearance in both T1‐weighted (T1w) and T2‐weighted (T2w) images. In T2w images there was a small isointense center surrounded by a relatively large hyperintense area. In T1w images, there was a large isointense centre with a relatively small hyperintense periphery. Such characteristics should prioritize hemangioma as a consideration in a progressive myelopathy due to an intramedullary mass.  相似文献   
4.
5.
Iridocorneal angle abnormalities were detected by gonioscopy in five dogs and one cat with glaucoma and intraocular neoplasms. Gonioscopic photographs and the histological abnormalities were compared in the neoplasia cases (the cat and two dogs). Congenital mesodermal, iridocorneal angle anomalies may occur more frequently in canine glaucoma than previously suspected.
Résumé. La gonioscopie a permis de déceler des anomalies de l'angle irido-corntén chez cinq chiens et un chat atteints de glaucome et de néoplasies intraoculaires. Les photographies gonioscopiques et les anomalies histologiques ont été comparées chez les animaux porteurs de néoplasmes (le chat et deux chiens). Des anomalies mésodermiques congénitales de l'angle irido-cornéen peuvent s'observer dans le glaucome du chien dans une proportion de cas plus grande qu'on ne l'admettait jusqu'ici.
Zusammenfassung. Mittels Gonioskopie wurden bei fünf Hunden und einer Katze mit Glaukom und intraokularen Neoplasmen iridocorneale Winkelanomalien festgestellt. Die gonioskopischen Photographien und die histologischen Anomalien wurden in den Neoplasmen-Fällen (die Katze und zwei Hunde) verglichen. Kongenitale mesodermale Anomalien des iridocornealen Winkels können beim Glaukom des Hundes haufiger auftreten als bisher angenommen wurde.  相似文献   
6.
PHILIP  M. S. 《Forestry》1975,48(2):123-138
The use of simulation as a tool in planning, predicting output,and as part of a system of forest management is discussed andillustrated by an example based on thirty-seven privately ownedforest estates in the Dee valley in north-east Scotland. The simulation model is described and the results of a low anda high level of felling and afforestation are compared. Thepredicted outputs from the simulation runs are compared withthe records of actual output from 1970 to 1972. The estimated increment and output were: Annual increment of crops 20 years and older 52,000 m3 Annual output at the ‘high’ level .4,000 m3 Annual output at the ‘low’ level 27,000 m3 Average actual annual output 1970–2 18,000 m3 The conclusions drawn from the results of the management studyin the forests of the Dee valley are:
  1. In the past, owners haveaccepted low rates of return from theirforest enterprise, theirprimary object being to re-create andmaintain a forest resourcesimilar to that which existed inthe past.
  2. Objective reappraisalsof the forest enterprise are exceptionaland management is constrainedoften by arbitrary, rigid, andsevere decisions that imposeunforeseen consequences on activitiesin both the forest andother parts of the estate.
  3. The current situation of the forestis very different from thatof the past and is continually changing.For example, the demandsof modern marketing and harvestingpractices are quite differentfrom those imposed even ten yearsago, and the proposed Wealthand Capital Transfer Taxes mayalter the relative importanceto the owners of forest incomeand capital.
Many forest owners in Britain now require a more objective approachto forest management with continuous reappraisal to ensure thattheir plans continue to serve their needs. As the financialresults of the forest enterprise are especially sensitive tothe felling and afforestation programmes, studies to answerthe following questions may be needed urgently:
  1. Can a higheroutput than that harvested at present be sustainedin the future?
  2. Should the rate of replacement of mature woods be altered?
  3. Does the current rate of afforestation best serve the objectsof management in the light of altered tax commitments and cashliquidity requirements?
Computer simulation can be a useful aid in planning providedthat reliable information on costs, prices, and growth ratesis available. Forest managers must be encouraged to collectthe necessary data.  相似文献   
7.
Objective— To report the prevalence of hypophosphatemia after renal transplantation in a historical cohort of cats. Design— Case series. Animals— Cats (n=86) that received a renal allograft. Methods— Medical records (January 200–June 2006) were reviewed. Signalment, clinical signs, pre‐ and postoperative diet, pre‐ and postoperative clinicopathologic variables, renal histopathology, and outcome were retrieved. Prevalence, onset, duration, treatment and associated clinical signs of hypophosphatemia were recorded. A χ2 test was used to compare hemolysis frequency between cats with normal serum phosphorus concentration or a single spurious low serum phosphorus concentration for <24 hours duration (group 1) and confirmed hypophosphatemia for >24 hours (group 2). A Cox proportional hazards model was used to evaluate the effects of hypophosphatemia on survival while controlling for other potentially confounding variables (age, sex, weight, body condition score, and pre‐ and 24 hours postoperative clinicopathologic variables). Results— Eighty‐six cats (mean age, 7.7 years) were identified. Hypophosphatemia occurred in 32 cats (37%), with a median onset of 2 days and median duration of 4 days. Treatment was initiated in 48 (56%) of hypophosphatemic cats. Survival and hemolysis frequency was not significantly different between groups, and no risk factors were identified. Conclusion— Hypophosphatemia occurs in cats after renal transplantation and does not affect survival. Clinical Relevance— The clinical importance of hypophosphatemia in renal transplant recipients remains unknown.  相似文献   
8.
通风方式对牛粪堆肥氨气排放与氮素转化的影响   总被引:9,自引:0,他引:9  
为揭示通风方式对好氧堆肥过程中氮素转化及损失的影响,设置连续通风T1(通风速率0.2L/(min·kg))和间歇通风T2(平均通风速率0.2L/(min·kg),通风10min,间歇10min)2个处理,以牛粪和玉米秸秆为原料在反应器中进行好氧堆肥试验。结果表明,堆肥结束后T1和T2处理总氮(TN)损失分别占初始 TN 23.25%和21.12%, TN的损失以NH3挥发为主,分别占 TN损失的74.76%和61.84%,而以N2O排放损失的氮仅占 TN损失的1.12%和1.37%。NH3挥发主要集中在堆肥初期,主要是因为较高的温度和pH值所致,至堆肥结束时T2处理NH3累积排放量比T1处理少24.37%。不同通风方式对堆肥过程中NH+4N和NO-3N的含量变化也产生显著影响,到堆肥结束时,T2处理相比T1处理,其NH+4N含量低11%,而NO-3N含量高6.7%,T2处理酸解总有机氮含量比T1处理高12.4%,说明间歇通风有利于硝化作用和氨同化作用的进行。结构方程模型(SEM)显示,T2处理不同有机氮对NH+4N含量的总影响从大到小顺序为:酰胺态氮(1.006)、氨基糖态氮(0.485)、酸解未知态氮(0.034)、氨基酸态氮(-0.852),说明NH+4N来源于酰胺态氮、氨基糖态氮和酸解未知态氮,同时NH+4N可以通过氨同化作用生成氨基酸态氮,间歇通风能促进NH+4N向氨基酸态氮的转化。间歇通风方式通过抑制有机氮向NH+4N的转化,降低堆肥过程中由NH3排放造成的氮素损失。  相似文献   
9.
First-pass nuclear angiocardiography was performed on 13 normal horses and 5 horses with confirmed left-to-right ventricular septal defects. Two methods of analyzing the ensuing pulmonary time-activity histograms for shunt recirculation through the lungs were evaluated: (1) pulmonary-to-systemic blood flow ratio (QP:QS), based on gamma variate modeling of the lung histogram, and (2) a simple count-ratio method (C2:C1). Normal values were QP:QS=1.17±0.04 and C2:C1=0.40±0.07. Values for the five horses with left-to-right shunts were QP:QS=2.94±0.13 and C2:C1=0.76±0.11. Both parameters showed significant differences (unpaired t -test; p <0.005) between the two groups, although separation was better with QP:QS.  相似文献   
10.
Two thousand sixty-three surgical procedures were performed on 1992 patients (1715 dogs and 277 cats). In a retrospective analysis, the procedures were categorized according to the expected degree of wound contamination, and corresponding wound infection rates were determined. The number of procedures in each category and the percent that became infected were as follows: clean (1100, 2.5%), clean-contaminated (554, 4.5%), contaminated (172, 5.8%), and dirty (237, 18.1%). The administration of antibiotics significantly reduced the frequency of wound infection in clean surgical procedures performed by senior veterinary students (p less than 0.05), but not in clean elective procedures performed by faculty or resident surgeons that required 90 minutes or less to complete. There was a significant correlation between elevation of rectal temperature postoperatively and increased duration of the surgical procedure. However, the rectal temperature measured the day after surgery was not an accurate predictor of wound infection.  相似文献   
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