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71.
In order to accurately estimate body composition at slaughter and to meet specific market targets, the influence of age at time of castration (surgical or immunological) on body composition and boar taint indicators must be determined for male pigs. In all, 48 males were randomly assigned to one of four management regimens: (1) entire male pigs (EM), (2) EM surgically castrated at ~40 kg BW and 10 weeks of age (late castrates; LC), (3) conventional, early surgical castrates (within 4 days of birth; EC) and (4) EM immunized with a gonadotropin-releasing hormone (GnRH) analog (primary dose at 30 kg BW and 8 weeks of age; booster dose at 70 kg and 14 weeks of age; IM). Pigs were fed corn and soybean meal-based diets that were not limiting in essential nutrients. Back fat was sampled on days −3, 8, 18 and 42, relative to administering the booster dose of GnRH analog at day 0, to determine androstenone concentrations (n=8 or 9/group). Fat androstenone concentrations in IM were lower than EM between days 8 and 42 after administering the booster dose (173 v. 863 ng/g, respectively; P<0.01), and were not different from surgically castrated males (EC and LC) after day 18. Slaughter occurred at ~115 kg BW, 42 days (6 weeks) after administering the booster dose for IM, and 10 and 20 weeks after surgical castration for LC and EC, respectively (n=8 or 9/group). At slaughter, live BW, liver weight as a percent of live BW, dissectible bone as a percent of cold carcass side, body protein and water contents and whole-body protein deposition decreased with time after surgical castration (linear; P<0.05), whereas dressing percentage, dissectible fat, probe fat depth and body fat content increased with time after surgical castration (linear; P<0.05). The IM had intermediate dressing percentage and dissected fat to EM and EC, whereas liver weight as a percent of live BW and body protein and lipid contents were not different from EM. Whole-body lipid deposition tended to be greater in IM than in EM between 14 and 20 weeks of age (373 v. 286 g/d; P=0.051). In conclusion, castration of male pigs after 6 weeks of age has a lasting effect on physical and chemical body composition. The relationship between time after castration and body composition may be developed to predict carcass composition and can be used to determine the ideal immunization schedule aimed at specific markets in the future.  相似文献   
72.
Delivery of therapeutic agents to enhance arteriovenous fistula (AVF) maturation can be administered either via intraluminal or external routes. The simple murine AVF model was combined with intraluminal administration of drug solution to the venous endothelium at the same time as fistula creation. Technical aspects of this model are discussed. Under general anesthesia, an abdominal incision is made and the aorta and inferior vena cava (IVC) are exposed. The infra-renal aorta and IVC are dissected for clamping. After proximal and distal clamping, the puncture site is exposed and a 25 G needle is used to puncture both walls of the aorta and into the IVC. Immediately after the puncture, a reporter gene-expressing viral vector was infused in the IVC via the same needle, followed by 15 min of incubation. The intraluminal administration method enabled more robust viral gene delivery to the venous endothelium compared to administration by the external route. This novel method of delivery will facilitate studies that explore the role of the endothelium in AVF maturation and enable intraluminal drug delivery at the time of surgical operation.  相似文献   
73.
痔是肛肠外科最常见的疾病之一,其治疗方式多种多样,尚无统一治疗标准。虽然,痔在临床上以保守治疗为主,但是对于II度以上有症状的痔,手术仍是目前最主要的治疗方式。关于有症状痔最佳治疗方式的争论仍在继续,无论是非手术治疗、传统的痔切除术还是痔的微创手术,都处于不断的改进和探索之中。临床医生总希望能够找到一项理想的具有复发率低、安全可靠、可早期恢复正常活动、术后疼痛轻微甚至无痛的手术方式。随着手术方式的改进和医疗技术的进步,痔的治疗效果也取得了很大的进步。本文就痔的非手术治疗、有创手术治疗以及微创手术治疗作一综述,为痔的临床治疗提供一定的理论依据。  相似文献   
74.
雄性手术不育对布氏田鼠社会行为的影响   总被引:1,自引:0,他引:1  
利用输精管结扎的方法对雄性布氏田鼠进行了不育处理,并研究了雄性不育后对布氏田鼠社会行为的影响.结果表明,与对照组相比,不育组中布氏田鼠的友好行为频次和对抗行为频次没有发生显著改变,而且不育组内部不育雄性和正常雄性之间在友好行为频次和对抗行为频次上也没有显著差异,说明结扎不育雄性对布氏田鼠的社会行为影响不大。  相似文献   
75.
doi:10.1111/j.1741‐2358.2009.00273.x
Non‐surgical treatment of gingival overgrowth induced by nifedipine: a case report on an elderly patient Drug‐induced gingival overgrowth (DIGO) is a significant problem for periodontologists and this side effect is frequently associated with three particular drugs: phenytoin, cyclosporin A and nifedipine. A case report of gingival overgrowth induced by nifedipine in an elderly patient treated with non‐surgical periodontal therapy is described. A 75‐year‐old male with generalised gingival overgrowth reported the problem of oral malodour and significant gingival bleeding. The medical history revealed a controlled hypertensive state and Cerebral Vascular Accident (CVA) 3 years prior to consultation. The diagnosis was gingival overgrowth associated with nifedipine, no other risk factors being identified. The patient had been taking nifedipine for 18 months, but after the consultation with the patient’s doctor, nifedipine was suspended, as the hypertension was controlled. Treatment consisted of meticulous oral hygiene instruction, scaling, root surface instrumentation and prophylaxis. Six months after the first intervention, clinical parameters revealed a significant improvement with a considerable reduction in gingival overgrowth, demonstrating the effect of non‐surgical periodontal therapy in severe cases of gingival overgrowth. Non‐surgical treatment of DIGO is a far less invasive technique than surgical approaches and has demonstrated an impressively positive treatment response. It should therefore be considered as a first treatment option for DIGO.  相似文献   
76.
Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. Impaired wound healing, which occurs in diabetic patients for example, can lead to severe unfavorable outcomes such as amputation. There is, therefore, an increasing impetus to develop novel agents that promote wound repair. The testing of these has been limited to large animal models such as swine, which are often impractical. Mice represent the ideal preclinical model, as they are economical and amenable to genetic manipulation, which allows for mechanistic investigation. However, wound healing in a mouse is fundamentally different to that of humans as it primarily occurs via contraction. Our murine model overcomes this by incorporating a splint around the wound. By splinting the wound, the repair process is then dependent on epithelialization, cellular proliferation and angiogenesis, which closely mirror the biological processes of human wound healing. Whilst requiring consistency and care, this murine model does not involve complicated surgical techniques and allows for the robust testing of promising agents that may, for example, promote angiogenesis or inhibit inflammation. Furthermore, each mouse acts as its own control as two wounds are prepared, enabling the application of both the test compound and the vehicle control on the same animal. In conclusion, we demonstrate a practical, easy-to-learn, and robust model of wound healing, which is comparable to that of humans.  相似文献   
77.
The hypotheses emerging from basic research on colorectal liver metastases must be tested in clinical situations for the adaptation of current treatment strategies. Pre-metastatic niches have been shown to exist in human colorectal synchronous metastases, with the liver parenchyma adjacent to the synchronous liver metastases providing a favorable, angiogenic environment for metastatic tumor growth. The role of the VEGF signaling pathway in liver regeneration and tumor growth remains unclear, but the use of antiangiogenic agents in combination with surgical treatment is almost certainly beneficial.  相似文献   
78.
Conventional techniques for implanting electrodes into axial swimming musculature of fish are reviewed. A new device is described that reduces time for electrode implantation, ensures constancy in electrode orientation, implantation depth, and separation distance. This device is inexpensive, simple to build, and easy to use.  相似文献   
79.
80.
The zinc and selenium levels of 40 surgical patients were monitored pre-and post-TPN. The initial selenium level was low normal, and the initial zinc level was also low. Both selenium and zinc are potent antioxidants involved in cellular defense against free radicals. Surgical patients are at risk for selenium and zinc deficiencies secondary to both increased needs and losses. TPN blood work protocols should include monitoring of selenium and zinc with supplementation of the nutrient solutions, as required.  相似文献   
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