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261.
To strengthen farm biosecurity, wildlife behaviors around livestock environments require significant attention. Livestock feed is considered one of essential factors that attract wildlife to the livestock environment. We experimentally studied wildlife response to cattle, swine, and chicken concentrated feeds in the forests surrounding poultry farms. In 14 feeding sites, four feed conditions were established: without feed (control); cattle feed; chicken feed; and swine feed. Wildlife behaviors at each feed point were monitored using infrared cameras. In 3,175 videos, 10 mammals were photographed on 10 or more occasions. Wildlife more frequently appeared at the points with feed than without feed. In addition, the number of videos that captured foraging or interest behaviors was largest for swine feed, followed by chicken feed, then cattle feed. There was a large difference among wildlife in their response to livestock feeds, although each species did not have a strong preference for a specific feed. Livestock feeds invite frequent visits by high and moderate response groups, especially omnivores and carnivores with omnivorous tendencies. Therefore, to protect against such wildlife intrusion, leftover feed and feed storage must be properly managed. This study also suggests that livestock feeds may not cause intrusions by rare response group species; hence, if their intrusions occur, they may be due to factors other than livestock feed. The study situation can partly reflect actual feed-stealing situations. The results will contribute to consider the properly management to protect livestock environments from wildlife intrusions.  相似文献   
262.
Canine transitional cell carcinoma (cTCC) is the most common naturally occurring bladder cancer and accounts for 1–2% of canine tumors. The prognosis is poor due to the high rate of invasiveness and metastasis at diagnosis. Sorafenib is a multi-kinase inhibitor that targets rapidly accelerated fibrosarcoma (RAF), vascular endothelial growth factor receptor (VEGFR)-1, VEGFR-2, VEGFR-3, platelet-derived growth factor receptor-β (PDGFR-β), and KIT. In previous studies, a somatic mutation of B-rapidly accelerated fibrosarcoma (BRAF) and expressions of VEGFR-2 and PDGFR-β were observed in over 80% of patients with cTCC. Therefore, in this study, we investigated the anti-tumor effects of sorafenib on cTCC. Five cTCC cell lines were used in the in vitro experiments. All five cTCC cell lines expressed VEGFR-2 and PDGFR-β and sorafenib showed growth inhibitory effect on cTCC cell lines. Cell cycle arrest at the G0/G1 phase and subsequent apoptosis were observed following sorafenib treatment. In the in vivo experiments, cTCC (Sora) cells were subcutaneously injected into nude mice. Mice were orally administered with sorafenib (30 mg/kg daily) for 14 days. Sorafenib inhibited tumor growth compared to vehicle control. The necrotic area in the tumor tissues was increased in the sorafenib-treated group. Sorafenib also inhibited angiogenesis in the tumor microenvironment. Thus, sorafenib may be potential therapeutic agent for cTCC via its direct anti-tumor effect and inhibition of angiogenesis.  相似文献   
263.
Intracytoplasmic sperm injection (ICSI) is an alternative technique to in vitro fertilization (IVF) for producing transferable blastocysts, especially in combination with cryopreserved oocytes, when the IVF system does not work sufficiently. The present study was conducted to directly compare the efficacy of producing bovine blastocysts by ICSI and IVF from vitrified-warmed and fresh oocytes. Denuded oocytes with a detectable first polar body were vitrified-warmed using a nylon mesh device. In the non-vitrified control group, blastocyst yields 8 days after IVF and ICSI were 32.0 and 26.8%, respectively. Oocyte vitrification and subsequent IVF resulted in an impaired blastocyst yield (15.0%); however, such a loss of efficacy due to vitrification was not observed in the ICSI group (blastocyst yield, 25.2%). The alignment of cortical granules beneath the oolemma was comparable between the fresh control and vitrified-warmed oocytes. Here, we report the high survival of vitrified-warmed bovine oocytes, as assessed by ICSI.  相似文献   
264.
To develop safe subcutaneous formulations and minimize the risk of local irritation, it is essential to optimize the composition of active pharmaceutical ingredients and excipients. Depending on the physicochemical properties of the active pharmaceutical ingredient, additional excipients may be required to improve the stability and solubility of the active pharmaceutical ingredient. However, some of these excipients may not have been previously used in injectable drugs. Owing to the lack of safety data for such excipients, especially those used in subcutaneous dosing, it is important to evaluate their potential for local irritation during the early stages of formulation development. We evaluated the tolerability of 44 formulations with 24 candidate novel excipients, such as surfactants, polymers, and lipids, in a single subcutaneous dose in rats. Excipient formulations were administered as single bolus subcutaneous injections with an injection volume of 1 mL. The injection sites were observed for 2 days, and macroscopic and microscopic examinations were conducted. Local tolerability was evaluated on the basis of severity, incidence, and pathophysiology of each finding. Formulations that caused tissue degeneration or necrosis, which is indicative of tissue injury, were determined to be irritative and poorly tolerated. A single-dose subcutaneous screening study in rats was considered effective in ranking the safety of candidate excipients during the formulation optimization phase.  相似文献   
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