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OBJECTIVE: To objectively evaluate the effect of transecting the tendon of the biceps brachii muscle (BBT), tendon of the infraspinatus muscle (IFS), or medial glenohumeral ligament (MGHL) on shoulder joint stability in canine cadavers. SAMPLE POPULATION: 81 forelimbs from mature dogs. PROCEDURE: Cadaver forelimbs were placed in a testing frame and axially preloaded with 4 kg of weight. Shoulder joint stability was tested in neutral joint position, flexion, and extension before and after transection of the BBT (n = 37), IFS (37), or MGHL (7). Humeral translation relative to the glenoid was induced by applying a 3-kg load in each of 3 directions (cranial, lateral, and medial) and quantitatively measured by use of an electromagnetic motion tracking system. Peak translational data were compared in each joint position before and after transection of the BBT, IFS, or MGHL. RESULTS: When tested in neutral position, the cranial, lateral, and medial translation of the humerus was significantly increased after BBT transection. In the flexed position, translation of the humerus in the cranial and lateral directions was significantly increased after BBT transection. In the extended position, the medial translation of the humerus was significantly increased after BBT transection. Complete medial luxation of all humeral heads occurred following transection of the MGHL. CONCLUSIONS AND CLINICAL RELEVANCE: The BBT contributes to passive shoulder joint stability in dogs, particularly in the neutral and flexed positions. It also provides medial stability during shoulder joint extension. Complete luxation of the joint occurs when the MGHL is transected.  相似文献   
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关于饲料中的抗氧化剂   总被引:1,自引:0,他引:1  
如今 ,许多饲料产品都以其抗氧化剂含量来促销。这样做的理由是 ,据说猪吃下抗氧化剂可保持自身健康 ,尤其是在猪遭受应激的时候 ,或者是猪面临疾病侵害的时候。因此 ,养猪者不禁要问 :这些抗氧化剂究竟是什么东西呢 ?吃这些东西怎么会有好处呢 ?这要从现代猪的代谢说起。现代猪在从活重30千克生长到 110千克期间 ,会以每天 340~ 4 5 0千克的速度合成瘦肉组织。为此 ,猪要通过大量的各种代谢过程将养分转化为机体物质。要平衡蛋白质的合成和分解 ,就需要高水平的代谢活动。代谢活动的水平在幼猪极高 ,例如 :体重 15千克的猪每2 8天就将心…  相似文献   
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A 3‐year‐old Labrador retriever was presented with acute onset seizures. Magnetic resonance imaging demonstrated an intra‐axial mass affecting the right temporal lobe of the brain. Surgical resection and histopathological findings were most consistent with a malignant peripheral nerve sheath tumor. After initial recovery, deterioration 3 months post surgery prompted euthanasia. Post‐mortem revealed a mass protruding from the ventral surface of the temporal lobe, encroaching upon the optic chiasm and invading the brain. Histopathology findings were again consistent with malignant peripheral nerve sheath tumor. Although rare, this tumor should be included as a possible differential diagnosis for intra‐axial brain masses in dogs.  相似文献   
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Objective-To describe clinical features of oral and maxillofacial osteomas in cats. Design-Retrospective case series. Animals-7 cats with oral or maxillofacial osteoma or both. Procedures-Medical records were reviewed for information on signalment, history, clinical signs, physical examination findings, diagnostic imaging findings, results of serum biochemical analyses and histologic testing, surgical procedures performed, and perioperative complications. Outcome was determined on the basis of follow-up telephone interviews of owners. Results-Cats ranged from 1 to 23 years of age. Clinical signs were observed in 5 cats and were attributed to the presence of the mass. Diagnostic imaging (radiography and computed tomography) and histologic examination confirmed the diagnosis of osteoma. Three cats were euthanatized; 1 cat was treated by mandibulectomy, 1 was treated by maxillectomy, and 2 were treated by debulking. At the time of follow-up at least 1 year after surgery, all 4 treated cats were alive, with owners reporting an acceptable quality of life. Conclusions and Clinical Relevance-Osteoma of the oral and maxillofacial regions is an uncommon tumor in cats. Most cats are examined during an advanced stage of the disease, when treatment options may be limited. Although osteoma is a benign tumor, the recommendation is to perform a clinical evaluation, diagnostic imaging, biopsy, and treatment early in the disease process, when less invasive surgical approaches may be feasible.  相似文献   
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人们对高产母猪的矿物质需要量研究较少。增加高产母猪日粮的矿物质含量,有助于维持高产母猪的繁殖性能,减短母猪发情间隔时间,降低重配率和淘汰率,延长使用时间。同时,日粮中矿物质的形式也十分重要。  相似文献   
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