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61.
62.
We have previously reported that newborn rats born to mothers fed a high n-6 polyunsaturated fatty acid (PUFA) (safflower oil) diet demonstrated increased n-6 PUFA in lung lipids and superior tolerance to high oxygen exposure. In the present study, we explored whether high n-3 PUFA might also protect against hyperoxic damage and by what mechanism. Adult female rats were fed either regular rat chow, a high n-3 (menhaden fish oil-based) diet, or a high n-6 (safflower oil-based) diet for 6 wk before and then throughout pregnancy and lactation. Newborn offspring of the high n-3 (fish oil) dams demonstrated increased n-3 PUFA (i.e. eicosapentaenoic and docosahexaenoic acid) and decreased n-6 PUFA (i.e. linoleic and arachidonic acid) in their lung lipids compared to the other two diet groups. The high n-6 (safflower oil) offspring had the opposite PUFA lung lipid pattern (with increases in total n-6 fatty acids and decreases in total n-3 fatty acids). The high n-3 offspring demonstrated markedly decreased lung levels of prostaglandin E2, F2 alpha and thromboxane B2, whereas the high n-6 offspring had higher eicosanoid levels than the regular diet offspring. Offspring of both high n-6 and high n-3 diet dams demonstrated essentially the same superior hyperoxic tolerance compared to regular diet offspring [7-d (greater than 95% O2) survival rates of 110/115 and 99/109, respectively, versus 70/91, p less than 0.01].(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
63.
The combination of small-animal PET and MRI data provides quantitative in vivo insights into cardiac pathophysiology, integrating information on biology and morphology. We sought to determine the feasibility of PET and MRI for the quantification of ischemic injury in the rat model. METHODS: Fourteen healthy male Wistar rats were studied with 18F-FDG PET and cine MRI. Myocardial viability was determined in a transmural myocardial infarction model in 12 additional rats, using 18F-FDG PET and delayed-enhancement MRI with gadolinium-diethylenetriaminepentaacetic acid. All PET was acquired with a dedicated small-animal PET system. MRI was performed on a 1.5-T clinical tomograph with a dedicated small-animal electrocardiographic triggering device and a small surface coil. RESULTS: In normal rats, 18F-FDG uptake was homogeneous throughout the left ventricle. The lowest mean uptake of the 18F-FDG was found in the apical regions (79% +/- 6.0% of maximum) and the highest uptake was in the anterior wall (93% +/- 4.3 % of maximum). Myocardial infarct size as determined by histology correlated well with defects of glucose metabolism obtained with 18F-FDG PET (r = 0.89) and also with delayed-enhancement MRI (r = 0.91). Left ventricular ejection fraction in normal rats measured by cine MRI was 57% +/- 5.4% and decreased to 38% +/- 12.9% (P < 0.001) in the myocardial infarction model. CONCLUSION: Integrating information from small-animal PET and clinical MRI instrumentation allows for the quantitative assessment of cardiac function and infarct size in the rat model. The MRI measurements of scar can be complemented by metabolic imaging, addressing the extent and severity of ischemic injury and providing endpoints for therapeutic interventions.  相似文献   
64.
Recently, anatomic or double-bundle reconstruction of the anterior cruciate ligament (ACL) has been presented in an effort to more accurately restore the native anatomy. These techniques create 2 tunnels in both the femur and tibia to reproduce the bundles of the ACL. However, the increased number of tunnels, particularly on the femoral side, has raised some concerns among authors and surgeons. We describe a technique to reconstruct the 2 distinct bundles of the ACL by using a single femoral tunnel and 2 tibial tunnels, the “hybrid” ACL reconstruction. The femoral tunnel is drilled through an anteromedial arthroscopy portal, which allows placement in a more anatomic position. Fixation in the femur is achieved with a novel device that separates a soft-tissue graft into 2 independently functioning bundles. Once fixed in the femur, the anteromedial and posterolateral bundles of the graft are passed through respective tunnels at the anatomic footprint on the tibia. These bundles are independently tensioned, which creates a reconconstruction that is similar to the native ACL. The technique presented provides surgeons with an alternative to other double-bundle techniques involving 4 tunnels.  相似文献   
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66.
While less emphasis has traditionally been placed on aesthetics in order to focus on successful osseointegration, increased success rates provided by contemporary endosseous root-form dental implants have improved postoperative peri-implant hard and soft tissue structures. The criteria for the evaluation of implant success should, therefore, include lack of pain, mobility, radiolucency, bone loss, infection, or paresthesia, as well as acceptability and stable aesthetics. This article discusses surgical means to preserve or restore hard and soft tissues around dental implants to achieve ideal and predictable outcomes.  相似文献   
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68.
Tissue-engineered skin substitutes such as Apligraf have emerged over the past 20 years as among the most carefully studied and efficacious of the advanced wound modalities. These products have been proven as effective enhancements to general wound care, promoting wound closure particularly in instances where conventional wound care fails. Marketed for hard-to-heal wounds since 1998, Apligraf has become part of standard wound care in many wound centers across the United States. Despite this situation, few general wound care guidelines incorporate advanced and active wound-healing technologies, such as tissue-engineered skin products. Because of this deficiency, appropriate patient selection and proper use of these product remain largely unaddressed within the general wound care community. Here, we describe the development of guidelines surrounding optimal use of the bilayered living cell therapy, Apligraf, in the treatment of the two types of lower extremity ulcers for which the product is FDA approved: venous leg ulcer and diabetic foot ulcer. The guidelines detailed in this article focus on the identification and selection of patients who are at risk for failure of standard wound care therapy and thus appropriate for Apligraf treatment. The intended audience for these guidelines is the general wound care practitioner, for whom the developed treatment algorithms and accompanying figure legends should provide practical, user-friendly direction simplifying both patient selection and appropriate use of Apligraf within the context of good wound-healing practice.  相似文献   
69.
Shellfish gathering has received comparatively little attention in the anthropological literature. Yet, the contribution of shellfish to the diet of indigenous societies can be significant. Reef and lagoon gleaning activities in Kiribati, Micronesia illustrate the importance of this class of invertebrates, particularly on urban South Tarawa. Proximate composition of 24 bivalves and gastropods add to our knowledge of the nutritional value of tropical shellfish. Microbiological contamination remains a problem, however, notably among inshore shellfish collected from Tarawa Lagoon. Assays on one species of cowrie (Cypraea tigris) confirm its toxicological properties, as suggested by some informants. The future of shellfish resources in Kiribati will need to address the issue of open access associated with an erosion of customary marine tenure.  相似文献   
70.
OBJECTIVE: The aim of this study was to evaluate the benefit of image fusion of CT (computertomography) and bone SPECT (single photon emission computed tomography) in diagnosis of head and neck cancer. METHODS AND PATIENTS: Computer based image fusion has been applied in 39 patients with suspected cancer in the oromaxillofacial region following CT and SPECT without any further hazard for the patients. Afterwards image fusion was set in comparision to simultaneously evaluation of CT and SPECT and histological findings. RESULTS: In 5 out of 39 patients SPECT/CT image fusion obtained more precise anatomical findings in tumour expansion than simultaneously evaluation of CT and SPECT. CONCLUSION: For planning of surgical and radiation therapy of oral and maxillofacial cancer, image fusion of CT/SPECT provides efficient and plastical diagnostic imaging. Particularly in complex anatomical regions like maxilla or base of the skull image fusion could be an additional device, if simultaneous evaluation of CT and SPECT is not clear.  相似文献   
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