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101.
OBJECTIVE: To compare the analgesic effects of buprenorphine, carprofen, and their combination in dogs undergoing ovariohysterectomy. STUDY DESIGN: Prospective, randomized blinded clinical study. ANIMALS: 60 dogs. METHODS: Treatments were buprenorphine 0.02 mg kg(-1), intramuscularly (IM) (group B); carprofen 4 mg kg(-1), subcutaneously (SC) (group C); or a combination of both (group CB). Anesthesia was induced with propofol and maintained with isoflurane. A Dynamic Interactive Visual Analog Scale (DIVAS, 0-100 mm) and the Glasgow Composite Pain Scale (GCMPS, 0-24) were used to evaluate comfort and sedation at baseline, 2, 4, 6, and 24 hours after extubation. Rescue analgesia was provided with buprenorphine (0.02 mg kg(-1)). Wound swelling measurements (WM) and a visual inflammation score (VIS) of the incision were made after surgery and 2, 4, 6, and 24 hours later. p < 0.05 was considered significant. RESULTS: Group C required more propofol (5.0 +/- 1.4 mg kg(-1)) compared with B (3.3 +/- 1.1 mg kg(-1)) and CB (3.2 +/- 0.7 mg kg(-1)); respectively, p = 0.0002 and 0.0001. Rescue analgesia was required in nine dogs. B had a higher GCMPS and DIVAS III score at 6 hours (2.6 +/- 2.5) and (23 +/- 22.5 mm) compared with C (1.0 +/- 1.3, 6 +/- 7.3 mm) and CB (1.5 +/- 1.4, 8 +/- 10.7 mm); respectively, p = 0.02 and 0.006. Group C had a lower sedation score at 2 hours (43 +/- 23.6 mm) compared with B (68 +/- 32.1 mm) and BC (69 +/- 22.1 mm); respectively, p = 0.03 and 0.004. Group B had a higher WM score at 2 hours (3 +/- 0.8 mm) compared with C (2 +/- 0.6 mm) p = 0.01 and at 6 hours (3 +/- 1 mm) compared with C (2 +/- 0.8 mm) and CB (2 +/- 0.8 mm); respectively, p = 0.01 and 0.008. VIS was not different between groups. CONCLUSION AND CLINICAL RELEVANCE: All treatments provided satisfactory analgesia for the first 6 hours and at 24 hours. C and CB pain score and WS were superior to B at 6 hours. No superior analgesic effect was noted when the drugs were combined.  相似文献   
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103.
Recent attention has been given to the influence of dietary factors on health and mental well-being. Oxidative stress is associated with many diseases including neurodegenerative disorders. Dietary flavonoids exert cardioprotective, chemopreventive, and neuroprotective effects. The biological activities of flavonoids have been attributed to their antioxidant, anti-inflammatory, and signaling properties. A clear understanding of the mechanisms of action, as either antioxidants or signaling molecules, is crucial for the application of flavonoids as interventions in neurodegeneration and as brain foods. Citrus flavonoids exert little adverse effect and have low or no cytotoxicity to healthy, normal cells. The main citrus flavonoids can also traverse the blood-brain barrier; hence, they are promising candidates for intervention in neurodegeneration and as constituents in brain foods. In this review, we discuss the bioactivity, multiple neuroprotection mechanisms, and antioxidant and signaling properties of citrus flavonoids. Receptor-mediated neuroprotective actions and parallel signaling pathways are also explored. Finally, the induction of cellular defense proteins against oxidative stress and neurotoxicity by hesperetin, a main and widespread citrus flavonoid, are also discussed. It is suggested that citrus fruits, which are rich in abundant sources of hesperetin and other flavonoids, are promising for the development of general food-based neuroprotection and brain foods.  相似文献   
104.

Purpose  

The aim of this study was to evaluate the roles of aluminum-based minerals, especially their surface Lewis acid sites (LASs), on the transformation and fate of chloroacetanilide herbicide contaminants when nucleophilic reagents are present.  相似文献   
105.
A regression analysis was used to develop a method to estimate the decrease in marketable tubers caused by late blight of potato (Phytophthora infestans), based on estimates of percentage loss in total tuber yield computed from a published method. The economic loss due to late blight in table stocks is the relative percentage marketable yield loss, calculated from the expression: {fx19-01} when total yield losses (in percentage) did not exceed 40%. A graphical method is presented as an alternative. Yield results from seven field experiments conducted in the Maritime Provinces of Canada during the period 1953 to 1971 were used in the study, where marketable tubers were defined as 2 1/4 inch or more in diameter.  相似文献   
106.
This study investigated the potential effects of natural products ursolic acid (UA) and oleanolic acid (OA) against HBx-mediated tumorigenic activities in vitro and in vivo. HBx transactivated Sp-1 and Smad 3/4 in Huh7 and FL83B hepatocytes and induced cell migration of Huh7 and HepG2. HBx also induced MMP-3 secretion in Huh7 and acted against TGF-β-induced apoptosis in Hep3B. UA almost completely blocked the HBx-mediated effects, while OA had a partial inhibitive effect. Utilization of specific MAPK inhibitors and immunoblotting demonstrated that UA selectively activated MAPK signaling in certain tested cells. Preintraperitoneal injection of UA fully prevented the tumor growth of HBV-containing 2.2.15 cells, while OA-treated mice had smaller tumors than the control group. Our results suggested that UA possesses a hepatoprotective ability and illustrated the evident effects against HBx-mediated tumorigenic activities without toxicity in a mouse model.  相似文献   
107.
Alzheimer's disease is neuropathologically characterized by amyloid β-protein (Aβ) deposition, resulting in neurotoxicity. Herein, we focused on the prevention of anthocyanins from amyloid-mediated neurodysfunction. The data demonstrated that combined exposure of Aβ(1-40) and Aβ(25-35) to Neuro-2A cells resulted in reactive oxygen species (ROS) production and perturbation of calcium homeostasis. The expressions of LXRα, ApoE, ABCA1, and seladin-1 genes were significantly down-regulated upon Aβ challenge. β-Secretase, the rate-limiting enzyme that catalyzes amyloid precursor protein transform to Aβ, was up-regulated by Aβ treatment. For the duration of Aβ stimulation, malvidin (Mal) or oenin (Oen; malvidin-3-O-glucoside) was added, and the protective effects were observed. Mal and Oen showed protective effects against Aβ-induced neurotoxicity through blocking ROS formation, preserving Ca(2+) homeostasis, and preventing Aβ-mediated perturbation of certain genes involved in Aβ metabolism and cellular defense. The present study implicates anthocyanin as a potential therapeutic candidate for the prevention of amyloid-mediated neurodysfunction.  相似文献   
108.
Application of one-dimensional transport considering multiple member of decay chain in a single rock fracture has been studied. Input sources for constant, pulse, impulse, Heaviside, and exponential decay have been used to demonstrate the suitability of relevant solutions. It shows that the breakthrough curves of dimensionless concentration for the three-member decay chain for Np-237 and the seven-member chain for Cm-246 can be well presented in the temporal and spatial domains. The analytical solutions of this study can clearly demonstrate the general form of contaminant transport with complete multiple-member decay chain in one-dimensional fractured or porous media of arbitrary analytical input sources without considering the matrix diffusion, which the conceptual model provides an alternative type to demonstrate the fate of radionuclide transport in the geosphere. The solutions are conservatively used to support the performance assessment for disposal site of radioactive waste. An application to a hybrid test site for the final disposal of spent nuclear fuel is newly demonstrated. Proposed solution to simulate the transport of nuclides in the one-dimensional pathway of host rock becomes feasible, so that the simulation and prediction of radionuclide transport of fractured media existing in geosphere can be conservatively performed in the future.  相似文献   
109.
Harvey murine sarcoma virus is a retrovirus which transforms cells by means of a single virally encoded protein called p21 has. We have determined the nucleotide sequence of 1.0 kilobase in the 5' half of the viral genome which encompasses the has coding sequences and its associated regulatory signals. The nucleotide sequence has identified the amino acid sequence of two additional overlapping polypeptides which share their reading frames and the carboxyl termini with p21 but which contain additional NH2-terminal amino acids.  相似文献   
110.
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